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Colony-forming Units (colony-forming + unit)
Kinds of Colony-forming Units Selected AbstractsAging Adversely Impacts Biological Properties of Human Bone Marrow-derived Mesenchymal Stem Cells: Implications for Tissue Engineering Heart Valve ConstructionARTIFICIAL ORGANS, Issue 3 2010Yuan Xin Abstract Our aim was to study the aging effects on the in vitro biological properties of bone marrow-derived mesenchymal stem cells (BMSCs) for construction of tissue-engineered heart valves. BMSCs were taken from teenagers with congenital heart diseases, and middle-aged and elderly patients with valvular diseases. Proliferative abilities were compared among the three groups by using colony-forming unit counting and growth curves (5-bromo-2,-deoxyuridine assay). Cell differentiation, vascular endothelial growth factor (VEGF) release under hypoxic condition, and migratory abilities were compared as well. Colony-forming units in the teenage group were significantly greater than those in the other two groups (P < 0.05), and significantly higher counts were observed in the middle age group than in the aged group (P < 0.05). Growth curves presented similar trends in which cells' proliferative abilities in the aged group decreased significantly (P < 0.05), while no differences were noted between the two nonaged groups. The differentiation potential to endothelial cells, osteoblasts and adipocytes, VEGF releases, and migratory abilities differed significantly between the aged group and nonaged groups (P < 0.05). However, no differences were noted between the two nonaged groups. BMSCs from older patients with heart valve diseases could be harvested and expanded successfully, and the phenotype and morphology were uniform as nonaged groups. However, the proliferative and differentiation properties of aged cells, as well as cytokine release and migratory abilities, are significantly impaired. [source] Human hematopoietic stem/progenitor-enriched CD34+ cells are mobilized into peripheral blood during stress related to ischemic stroke or acute myocardial infarctionEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 6 2005E. Paczkowska Abstract:, The hematopoietic and non-hematopoietic stem/progenitor cells harvested directly from the bone marrow (BM) or G-CSF mobilized peripheral blood were demonstrated to play an important role in regeneration of damaged organs (1, 2). Here, we asked if the stroke- or acute heart infarct-related stress triggers mobilization of stem/progenitor-enriched CD34+cells from the BM into the peripheral blood, which subsequently could contribute to regeneration of damaged tissues. To address this question the peripheral blood samples were harvested from patients with ischemic stroke during the first 24 h of manifestation of symptoms and on the second and sixth day afterwards or during the first 24 h of acute cardiac pain as well as on the second and sixth day of infarct. We measured in these patients (i) percentage of circulating hematopoietic stem/progenitor-enriched CD34+ cells in peripheral blood by employing fluorescence activated cell sorter (FACS) and (ii) number of hematopoietic progenitor cells for the granulocyte-monocytic colony-forming unit (CFU-GM) and erythoid burst-forming unit (BFU-E) lineages circulating in peripheral blood. We concluded that stress related to ischemic stroke or acute myocardial infarction triggers the mobilization of hematopoietic stem/progenitor-enriched CD34+ cells from the BM into peripheral blood. These circulating stem/progenitor-enriched CD34+ cells may contribute to the regeneration of ischemic tissues, however, this possibility requires further studies. [source] Comparison of different methods of bacterial detection in blood componentsISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue 1 2009M. Schmidt Background, Over the last two decades, the residual risk of acquiring a transfusion-transmitted viral infection has been reduced to less than 1 : 1 000 000 via improvements in different techniques (e.g. donor selection, leuco-depletion, introduction of 3rd or 4th generation enzyme-linked immunosorbent assays and mini-pool nucleic acid testing (MP-NAT). In contrast, the risk for transfusion-associated bacterial infections has remained fairly stable, and is estimated to be in a range between 1 : 2000 and 1 : 3000. Platelets are at an especially higher risk for bacterial contamination, because they are stored at room temperature, which provides good culture conditions for a broad range of bacterial strains. To improve bacterial safety of blood products, different detection systems have been developed that can be divided into culture systems like BacT/ALERT or Pall eBDS, rapid detection systems like NAT systems, immunoassays and systems based on the FACS technique. Culture systems are used for routine bacterial screening of platelets in many countries, whereas rapid detection systems so far are mainly used in experimental spiking studies. Nevertheless, pathogen-reduction systems are currently available for platelet concentrates and plasma, and are under investigation for erythrocytes. Methods, In this review, the functional principles of the different assays are described and discussed with regard to their analytical sensitivity, analytical specificity, diagnostic sensitivity, diagnostic specificity and clinical efficiency. The detection methods were clustered into three groups: (i) detection systems currently used for routine screening of blood products, (ii) experimental detection systems ready to use for routine screening of blood products, and (iii) new experimental detection systems that need to be investigated in additional spiking studies and clinical trials. Results, A recent International Society of Blood Transfusion international forum reported on bacterial detection methods in 12 countries. Eight countries have implemented BacT/ALERT into blood donor screening, whereas in three countries only quality controls were done by culture methods. In one country, shelf-life was reduced to 3 days, so no bacterial screening was implemented. Screening data with culture methods can be used to investigate the prevalence of bacterial contamination in platelets. Differing results between the countries could be explained by different test definitions and different test strategies. Nevertheless, false-negative results causing severe transfusion-related septic reactions have been reported all over the world due to a residual risk of sample errors. Rapid screening systems NAT and FACS assays have improved over the last few years and are now ready to be implemented in routine screening. Non-specific amplification in NAT can be prevented by pre-treatment with Sau3AI, filtration of NAT reagents, or reduction of the number of polymerase chain reaction cycles. FACS systems offer easy fully automated handling and a handling time of only 5 min, which could be an option for re-testing day-5 platelets. New screening approaches like immunoassays, detection of bacterial adenosine triphosphate, or detection of esterase activity need to be investigated in additional studies. Conclusion, Bacterial screening of blood products, especially platelets, can be done with a broad range of technologies. The ideal system should be able to detect one colony-forming unit per blood bag without a delay in the release process. Currently, we are far away from such an ideal screening system. Nevertheless, pathogen-inactivation systems are available, but a system for all blood components will not be expected in the next few years. Therefore, existing culture systems should be complemented by rapid systems like NAT or FACS especially for day-5 platelets. [source] LDL lipid apheresis rapidly increases peripheral endothelial progenitor cell competenceJOURNAL OF CLINICAL APHERESIS, Issue 5 2009Daniel Patschan Abstract Background and Aim: Endothelial progenitor cells (EPCs) have been shown to promote neovascularization under physiologic and pathologic conditions. Statins have been documented to increase the total number of circulating EPCs in long-term treated patients. Lipid apheresis is used to treat patient with refractory hyperlipidemia. The aim of our study was to evaluate whether lipid apheresis is associated with EPC mobilization. Methods: Thirteen patients with refractory hyperlipidemia (analysis at the beginning and at the end of a single lipid apheresis treatment) and 10 healthy controls were included into the study. For quantifying total peripheral EPCs, CD133+/Flk-1+ myelo-monocytic blood cells were enumerated by flow cytometry. The proliferative potential of EPCs was evaluated by a "colony-forming unit" assay. In some patients, EPC eNOS expression was evaluated before and after treatment. Results: Circulating EPCs and the cells' proliferative activity were lower in hyperlipidemia patients as compared to controls (0.14 ± 0.07 vs. 0.6 ± 0.14, P = 0.01, and 13.9 ± 4.9 vs. 45.6 ± 8.1, P = 0.0007). Lipid apheresis treatment was not associated with an increase in total EPCs. The cells' proliferative activity was strongly stimulated by lipid apheresis as reflected by an increase in the number of EPC colonies (13.9 ± 4.9 to 34.1 ± 7.3, P = 0.035). Analysis of EPC eNOS expression revealed a threefold increase in the cellular expression intensity after lipid apheresis. Conclusions: Patients with refractory hyperlipidemia exhibit lower peripheral EPC numbers and a lower proliferative activity of circulating EPCs than healthy controls. A single lipid apheresis treatment significantly stimulates EPC proliferation, it furthermore increases cellular eNOS. In summary, these results show that lipid apheresis mediates beneficial effects on the EPC system as an essential element in the process of vascular repair in the human organism. J. Clin. Apheresis 2009. © 2009 Wiley-Liss, Inc. [source] Inhibition of bacterial translation and growth by peptide nucleic acids targeted to domain II of 23S rRNAJOURNAL OF PEPTIDE SCIENCE, Issue 4 2007Huang Xue-Wen Abstract The objective of this work was to study the inhibitory effects of antisense peptide nucleic acids (PNAs) targeted to domain II of 23S rRNA on bacterial translation and growth. In this paper, we report that PNA(G1138) or peptide-PNA(G1138) targeted to domain II of 23S rRNA can inhibit both translation in vitro (in a cell-free translation system) and bacterial growth in vivo. The inhibitory concentration (IC50) and the minimum inhibiting concentration (MIC) are 0.15 and 10 µM, respectively. The inhibition effect of PNA(G1138) in vitro is somewhat lower than that of tetracycline (IC50 = 0.12 µM), but the MIC of peptide-PNA(G1138) against Escherichia coli is significantly higher than that of tetracycline (MIC = 4 µM). Further studies based on similar colony-forming unit (CFU) assays showed that peptide-PNA(G1138) at 10 µM is bactericidal, but the bactericidal effect is less effective than that of tetracycline. Nevertheless, the results demonstrated that the peptide-PNA(G1138) treatment is bactericidal in a dose- and sequence-dependent manner and that the G1138 site of 23S rRNA is a possible sequence target for designing novel PNA-based antibiotics. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd. [source] Inhibition of Hematopoietic Progenitor Cell Proliferation by Ethanol in Human Immunodeficiency Virus Type 1 Tat-Expressing Transgenic MiceALCOHOLISM, Issue 3 2001Om Prakash Background: A number of hematological abnormalities are associated with both human immunodeficiency virus type 1 (HIV-1) infection and alcohol abuse. There is little information on how alcohol abuse might further influence the survival and growth of hematopoietic progenitors in HIV-infected individuals in the presence of immune system abnormalities and anti-HIV drugs. Because there is evidence that viral transactivator Tat itself can induce hematopoietic suppression, in this study we examined the role of ethanol as a cofactor in transgenic mice that expressed HIV-1 Tat protein. Methods: Tat transgenic mice and nontransgenic littermates were given ethanol (20% v/v) and the anti-HIV drug 3,-azido-3,-deoxythymidine (AZT; 1 mg/ml) in drinking water. Immunosuppression in mice was induced by weekly intraperitoneal injections of anti-CD4 antibody. Hematopoiesis was examined by erythroid colony forming unit (CFU-E) and granulocyte/macrophage colony-forming unit (CFU-GM) assays of the bone marrow progenitor cells. Results: Administration of ethanol for 7 weeks resulted in a 50% decrease in the proliferative capacity of CFU-E- and CFU-GM-derived progenitors from transgenic mice compared with that of ethanol-treated nontransgenic controls. Similar decreases also were observed in transgenic mice treated with AZT or a combination of AZT and ethanol. Furthermore, ethanol and AZT were significantly more toxic to the granulopoietic progenitors (40,50% inhibition) than to the erythropoietic progenitors (10,20% inhibition) in Tat transgenic mice. Although a 10 day exposure of Tat transgenic and nontransgenic mice to a combination of ethanol and AZT had no suppressive effect on the erythropoietic and granulopoietic progenitor cells, there was a marked decrease (40,60%) in CFU-GM in mice made immunodeficient by CD4+ T-lymphocyte depletion. The ethanol-treated Tat transgenic mice but not the nontransgenic littermates also showed a significant decrease (25%) in CFU-GM. Conclusion: Our in vivo study strongly suggests that ethanol ingestion in HIV-1-infected individuals, particularly those on antiretroviral drugs, might increase bone marrow toxicity and contribute to HIV-1-associated hematopoietic impairment. [source] Efficacy of an experimentally inactivated Streptococcus agalactiae vaccine in Nile tilapia (Oreochromis niloticus) reared in BrazilAQUACULTURE RESEARCH, Issue 10 2010Lucienne Garcia Pretto-Giordano Abstract Tilapia aquaculture is one of the fastest-growing segments of fish production in Brazil. Nile tilapia (Oreochromis niloticus) is largely cultivated in the state of Parana, where Streptococcus agalactiae is the cause of severe disease outbreaks. The objective of this paper was to evaluate an inactivated S. agalactiae vaccine in tilapia for the control of streptococcal disease outbreaks. Tilapia, weighing approximately 20 g each, were intraperitoneally (i.p.) inoculated with 0.1 mL of the vaccine at a dose of 2.0 × 108 colony-forming unit (CFU) mL,1. One group of tilapia (treatment 1) received one vaccine dose, and the other group of tilapia (treatment 2) received two doses, with an interval of 21 days. The control group was i.p. inoculated with 0.1 mL tryptic soy broth fish,1. Immunized and control tilapia were i.p. challenged with 0.1 mL of 3.0 × 107 CFU mL,1 at 30 days post vaccination. The fish were monitored daily for disease signs and for mortality for 16 days post challenge. A statistically significant difference (P=0.0045) was found between the mortality of treatments 1 and 2. The value of relative per cent of survival of 83.6% and 96.4%, respectively, indicate that this vaccine was efficient in Nile tilapia. [source] Large-scale extraction and characterization of CD271+ multipotential stromal cells from trabecular bone in health and osteoarthritis: Implications for bone regeneration strategies based on uncultured or minimally cultured multipotential stromal cells,ARTHRITIS & RHEUMATISM, Issue 7 2010E. Jones Objective To test the hypothesis that CD45lowCD271+ bone marrow multipotential stromal cells (MSCs) are abundant in the trabecular bone niche and to explore their functional "fitness" in health and osteoarthritis (OA). Methods Following enzymatic extraction, MSC release was evaluated using colony-forming unit,fibroblast (CFU-F) and colony-forming unit,osteoblast assays, flow cytometry, and confocal microscopy. CD45lowCD271+ cells isolated by fluorescence-activated cell sorting were enumerated and expanded under standard and clonal conditions. Their proliferative and osteogenic potencies were assessed in relation to donor age and compared with those of aspirated CD45lowCD271+ cells. In vitro and in vivo MSC "aging" was measured using quantitative polymerase chain reaction,based telomere length analysis, and standard differentiation assays were utilized to demonstrate multipotentiality. Results Cellular isolates from trabecular bone cavities contained ,65-fold more CD45lowCD271+ cells compared with aspirates (P < 0.0001) (median 1.89% [n = 39] and 0.029% [n = 46], respectively), concordant with increased CFU-F release. Aspirated and enzymatically released CD45lowCD271+ cells had identical MSC phenotypes (,100% CD73+CD105+CD13+, ,50,60% CD146+CD106+CD166+) and contained large proportions of highly clonogenic multipotential cells. In vitro osteogenic potency of freshly isolated CD45lowCD271+ cells was comparable with, and often above, that of early-passage MSCs (8,14%). Their frequency and in vivo telomere status in OA bone were similar to those in bone from age-matched controls. Conclusion Our findings show that CD45lowCD271+ MSCs are abundant in the trabecular bone cavity and indistinguishable from aspirated CD45lowCD271+ MSCs. In OA they display aging-related loss of proliferation but no gross osteogenic abnormality. These findings offer new opportunities for direct study of MSCs in musculoskeletal diseases without the requirement for culture expansion. They are also relevant for direct therapeutic exploitation of prospectively isolated, minimally cultured MSCs in trauma and OA. [source] Oral delivery of tumor-targeting Salmonella exhibits promising therapeutic efficacy and low toxicityCANCER SCIENCE, Issue 12 2009Guo Chen Tumor-targeting bacteria have been developed as powerful anticancer agents. Salmonella typhimurium VNP20009, a representative tumor-targeting strain, has been systemically administered as a single-agent therapy at doses of 1 × 106 to 3 × 106 colony-forming unit (cfu)/mouse, or in combination with other antitumor agents at doses of 1 × 104 to 2 × 105 cfu/mouse. Recently, we reported that oral delivery of VNP20009 at the dose of 1 × 109 cfu/mouse induced significant anticancer effects comparable to that induced by systemic administration of this strain at 1 × 104 cfu/mouse. To further address the efficacy and safety of oral administration of bacteria, here we performed a systemically comparative analysis of anticancer efficacy and toxicity of VNP20009 administered: (i) orally at a dose of 1 × 109 cfu/mouse (VNP9-oral); (ii) intraperitoneally at a dose of 1 × 104 cfu/mouse (VNP4-i.p.); or (iii) intraperitoneally at a dose of 1 × 106 cfu/mouse in tumor-free and tumor-bearing murine models. The results showed that VNP9-oral, similar to VNP4-i.p., induced significant tumor growth inhibition whereas VNP6-i.p. induced better anticancer effect in the B16F10 melanoma model. Among three treatments, VNP9-oral induced the mildest and reversible toxicity whereas VNP6-i.p. resulted in the most serious and irreversible toxicities when compared to other two treatments. Moreover, the combination of VNP9-oral with a low dose of chemotherapeutics produced comparable antitumor effects but displayed significantly reduced toxicity when compared to VNP6-i.p. The findings demonstrated that oral administration, as a novel avenue in the application of bacteria, is highly safe and effective. Moreover, the present preclinical study should facilitate the optimization of bacterial therapies with improved anticancer efficacy and reduced adverse effects in future clinical trials. (Cancer Sci 2009; 100: 2437,2443) [source] The influence of 3,3,,5-triiodo- l -thyronine on human haematopoiesisCELL PROLIFERATION, Issue 3 2007K. Grymu The role of the 3,3,,5-triiodo- l -thyronine (T3) in normal human haematopoiesis at the cellular and molecular levels has not been determined. In this study, it was revealed that the human haematopoietic system might be directly depended on T3 influence. Materials and methods: We detected the TR,1 and TR,1 gene expression at the mRNA level in human cord blood, peripheral blood and bone marrow CD34+ -enriched progenitor cells, using the RT-PCR method. Furthermore, we performed Western blotting to prove TR,1 and TR,1 expression occurs at the protein level in human cord blood, peripheral blood and bone marrow CD34+ cells. In addition, the examined populations of cells were exposed in serum-free conditions to increasing doses of T3 and were subsequently investigated for clonogenic growth of granulocyte-macrophage colony-forming unit and erythrocyte burst-forming unit in methylcellulose cultures, and for the level of apoptosis, by employing annexin V staining and the terminal deoxynucleotidyltransferase-mediated dUTP nick-end labelling method. We investigated expression levels of apoptosis-related Bax and antiapoptotic Bcl-2 and Bcl-xL genes in the examined cells. Results: We found that exposure to higher and lower than normal concentration of thyroid hormone significantly influenced clonogenecity and induced apoptosis in human haematopoietic progenitor cells. Conclusions: This study expands the understanding of the role of thyroid disorders in normal human haematopoiesis and indicates a direct influence of T3 on this process. [source] The influence of antisense oligonucleotides against STAT5 on the regulation of normal haematopoiesis in a bone marrow modelCELL PROLIFERATION, Issue 3 2004M. Ba, kiewicz-Masiuk The STAT5 (signal transducers and activators of transcription) proteins are members of a family of signal transducers and activators of transcription that can be activated after cytokine stimulation. Their binding to promoters of different genes influences cell proliferation, differentiation and survival. It is suggested that they play an important role in haematopoiesis, however, the question of the real function of STAT5 proteins requires further examination. The aim of our study was to investigate the role of STAT5 in the proliferation and apoptosis of normal haematopoietic bone marrow cells derived from heparinized cadaveric organ donors (HCOD). We applied antisense oligodeoxynucleotides (ODNs) to block STAT5A and STAT5B at the mRNA level and the reverse transcription polymerase chain reaction method to study STAT5 mRNA expression in the cells after incubation with ODNs. Moreover, we performed Western blot analysis of the STAT5A protein after exposure to antisense STAT5A. We analysed the clonogenicity of the colony-forming unit of granulocytes,macrophages and the burst-forming unit of erythrocytes in methylcellulose cultures according to the type and the dose of ODNs. We also examined apoptosis induced in bone marrow mononuclear and CD34+ cells by employing annexin V staining and the TUNEL method using flow cytometry (FACScan). We found that the perturbation of STAT5 expression decreased the clonogenicity of bone marrow haematopoietic cells. However, we did not observe any significant increase in the percentage of apoptotic cells after incubation with antisense ODNs. It was concluded that the STAT5 proteins play a significant role in the proliferation of human bone marrow cells harvested from HCOD. These proteins might be critical in the regulation of haematopoiesis, especially under stress conditions. [source] Acute effects of the antibiotic oxytetracycline on the bacterial community of the grass shrimp, Palaemonetes pugio,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2009Miguel Uyaguari Abstract The toxicity of oxytetracycline (OTC) was evaluated in adult grass shrimp, Palaemonetes pugio. Initially, static acute (96 h) toxicity tests were conducted with shrimp exposed from 0 to 1,000 mg/L OTC. A calculated lethal concentration 50% value of 683.30 mg/L OTC (95% confidence interval 610.85,764.40 mg/L) was determined from these tests, along with a lowest-observable-effect concentration of 750 mg/L and no-observable-effect concentration of 500 mg/L. Moreover, chronic sublethal effects of OTC exposure on grass shrimp intestinal bacterial population were assessed using doses from 0 to 32 mg/L OTC. The total viable counts in digestive tract content had levels between 5.2 and 1 × 104 colony-forming units per gram of tissue at times 0 and 96 h, respectively. Aeromonas hydrophila were the most resistant isolates (27.78%) to OTC exposure. Vibrio alginolyticus showed significant positive growth following exposure to OTC, whereas other bacterial species abundance declined over time. A total of 268 bacterial isolates were screened using antibiotic resistance analysis from a library containing 459 isolates. Among the tested isolates from the OTC treatments, 15.4% were resistant to OTC and 84.6% were OTC sensitive. Oxytetracycline was generally not consistently quantifiable with liquid chromatography-mass spectroscopy technique in shrimp homogenates. The only peak detected was at the 32 mg/L dose of OTC at 96 h. Nevertheless, OTC had a significant biological effect on the bacterial population. Antibiotic resistance to five other antibiotics (penicillin G, sulfathiazole, trimethoprim, trimethoprim and sulfamethoxazole, and tetracycline) was strongly associated with OTC exposures. The present study indicates that OTC toxicity effects in P. pugio and changes in the shrimp microbial community would only be expected under special circumstances. [source] Protection of hematopoietic cells from O6 -alkylation damage by O6 -methylguanine DNA methyltransferase gene transfer: studies with different O6 -alkylating agents and retroviral backbonesEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2001Michael Jansen Abstract: Overexpression of O6 -methylguanine DNA methyltransferase (MGMT) can protect hematopoietic cells from O6 -alkylation damage. To identify possible clinical applications of this technology we compared the effect of MGMT gene transfer on the hematotoxicity induced by different O6 -alkylating agents in clinical use: the chloroethylnitrosoureas ACNU, BCNU, CCNU and the tetrazine derivative temozolomide. In addition, various retroviral vectors expressing the MGMT-cDNA were investigated to identify optimal viral backbones for hematoprotection by MGMT expression. Protection from ACNU, BCNU, CCNU or temozolomide toxicity was evaluated utilizing a Moloney murine leukemia virus-based retroviral vector (N2/Zip-PGK-MGMT) to transduce primary murine bone marrow cells. Increased resistance in murine colony-forming units (CFU) was demonstrated for all four drugs. In comparison to mock-transduced controls, after transduction with N2/Zip-PGK-MGMT the IC50 for CFU increased on average 4.7-fold for ACNU, 2.5-fold for BCNU, 6.3-fold for CCNU and 1.5-fold for temozolomide. To study the effect of the retroviral backbone on hematoprotection various vectors expressing the human MGMT-cDNA from a murine embryonic sarcoma virus LTR (MSCV-MGMT) or a hybrid spleen focus-forming/murine embryonic sarcoma virus LTR (SF1-MGMT) were compared with the N2/Zip-PGK-MGMT vector. While all vectors increased resistance of transduced human CFU to ACNU, the SF1-MGMT construct was most efficient especially at high ACNU concentrations (8,12 µg/ml). Similar results were obtained for protection of murine high-proliferative-potential colony-forming cells. These data may help to optimize treatment design and retroviral constructs in future clinical studies aiming at hematoprotection by MGMT gene transfer. [source] Fluorescence-controlled Er:YAG laser for caries removal in permanent teeth: a randomized clinical trialEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2008Henrik Dommisch The aim of this randomized clinical study was to compare the efficacy of a fluorescence-controlled erbium-loaded yttrium aluminum garnet (Er:YAG) laser with conventional bur treatment for caries therapy in adults. Twenty-six patients with 102 carious lesions were treated using either the Er:YAG laser, at threshold levels of 7, 8, 9, and 10 [U], or rotary burs. Both techniques were applied to each lesion at separate locations. After treatment, dentine samples were obtained using a carbide bur. The viable counts of Streptococcus mutans (SM) and lactobacilli (LB) [expressed as colony-forming units (log10 CFUs)], treatment time, pain, vibration, and sound intensity were determined. The median numbers of CFUs for SM and LB were not statistically different between laser and bur treatment at threshold levels 7 and 8 [U]. At threshold levels 9 and 10 [U], the median number of CFUs for LB [1.11 (range: 0.00,2.04)] were significantly higher following laser treatment than following bur treatment [0.30 (range: 0.00,0.60)]. The results indicate that treatment with a fluorescence-controlled Er:YAG laser at threshold levels of 7 and 8 removed caries to a level similar to that achieved using conventional bur treatment, with clinically irrelevant amounts of remaining bacteria. Although more time consuming, laser treatment provided higher patient comfort than bur treatment. [source] Enzyme-Based Nanoscale Composites for Use as Active Decontamination SurfacesADVANCED FUNCTIONAL MATERIALS, Issue 3 2010Cerasela Zoica Dinu Abstract Perhydrolase S54V (AcT) effectively catalyzes the perhydrolysis of propylene glycol diacetate (PGD) to generate peracetic acid (PAA). PAA is a potent oxidant used for sanitization and disinfection, with broad effectiveness against bacteria, yeasts, fungi, and spores. In this study, active and stable composites are developed by incorporating AcT,carbon nanotube conjugates into polymer and latex-based paint. At a conjugate loading of 0.16% (w/v), the composite generated 11,mM PAA in 20,min, capable of killing more than 99% spores initially charged at 106 colony-forming units per milliliter. [source] Mechanism of Action of Low Recurrence of Gastritis Caused by Helicobacter pylori with the Type II Urease B GeneHELICOBACTER, Issue 2 2004Md. Badruzzaman ABSTRACT Background., Low recurrence of gastritis is seen in patients infected with Helicobacter pylori carrying the type II urease B gene, compared with H. pylori carrying types I and III. The underlying mechanism has been studied in terms of the urease activity and interleukin (IL)-8 production capacity of different strains of H. pylori. Materials and Methods., Forty-five patients infected with different strains of H. pylori (type I; 15, type II; 15 and type III; 15) were enrolled in the study. H. pylori was isolated from gastric mucosa and cultured in the presence of urea at pH 5.5 to evaluate urease activity. The capacity of different strains of H. pylori to induce IL-8 mRNA and IL-8 from a human gastric cancer cell line and human peripheral blood mononuclear cells was evaluated. Results., The urease activity of type II H. pylori[523 ± 228 µg of ammonia/dl/108 colony-forming units (CFU)/ml] was significantly lower than that of type I (1355 ± 1369 µg of ammonia/dl/108 CFU/ml) and type III (1442 ± 2229 µg of ammonia/dl/108 CFU/ml) (p < .05). Gastric cancer cells cocultured with type II H. pylori produced lower levels of IL-8 mRNA compared with type I and type III H. pylori. The levels of IL-8 were also significantly lower in cultures induced by type II H. pylori compared with those induced by type I and type III H. pylori. Peripheral blood mononuclear cells also produced lower levels of IL-8 when cocultured with type II compared with type I H. pylori. Conclusions., These results indicate that both the lower level of urease activity and the low IL-8-inducing capacity of type II H. pylori might underlie the lower recurrence rate of gastritis caused by type II H. pylori. [source] Significance of circulating endothelial progenitor cells in hepatocellular carcinoma,HEPATOLOGY, Issue 4 2006Joanna W. Y. Ho This study evaluated the significance of circulating bone marrow-derived endothelial progenitor cells (EPCs) in patients with hepatocellular carcinoma (HCC), a solid tumor with rich neovasculature. Eighty patients with HCC were recruited for the study, and 16 patients with liver cirrhosis and 14 healthy subjects were also included for comparison. Blood samples were taken before treatment. Total mononuclear cells were isolated from peripheral blood, preplated to eliminate mature circulating endothelial cells, and colony-forming units (CFUs) formed by circulating EPCs were counted. To validate the CFU scores, FACS quantification of EPCs using CD133, VEGFR2, and CD34 as markers was performed in 30 cases. Our study showed significantly higher mean CFU scores in patients with HCC compared to patients with cirrhosis and healthy controls (P = .001 and .009, respectively). Furthermore, the CFU scores of patients with HCC positively correlated with levels of serum ,-fetoprotein (r = .303, P = .017), plasma VEGF (r = .242, P = .035), and plasma interleukin-8 (IL-8) (r = .258, P = .025). Patients with unresectable HCC had higher CFU scores than patients with resectable tumors (P = .027). Furthermore, for those who underwent curative surgery, higher preoperative CFU scores were observed in patients with recurrence within 1 year compared with those who were disease-free after 1 year (P = .013). In conclusion, higher circulating levels of EPCs are seen in patients with advanced unresectable HCC as compared to patients with resectable HCC or those with liver cirrhosis. Our evidence supports the potential use of circulating level of EPCs as a prognostic marker in patients with HCC. (HEPATOLOGY 2006;44:836,843.) [source] Kupffer cell,derived interleukin 10 is responsible for impaired bacterial clearance in bile duct,ligated miceHEPATOLOGY, Issue 2 2004Tetsuya Abe Extrahepatic cholestasis often evokes liver injury with hepatocyte apoptosis, aberrant cytokine production, and,most importantly,postoperative septic complications. To clarify the involvement of aberrant cytokine production and hepatocyte apoptosis in impaired resistance to bacterial infection in obstructive cholestasis, C57BL/6 mice or Fas-mutated lpr mice were inoculated intraperitoneally with 107 colony-forming units of Escherichia coli 5 days after bile duct ligation (BDL) or sham celiotomy. Cytokine levels in sera, liver, and immune cells were assessed via enzyme-linked immunosorbent assay or real-time reverse-transcriptase polymerase chain reaction. BDL mice showed delayed clearance of E. coli in peritoneal cavity, liver, and spleen. Significantly higher levels of serum interleukin (IL) 10 with lower levels of IL-12p40 were observed in BDL mice following E. coli infection. Interferon , production from liver lymphocytes in BDL mice was not increased after E. coli infection either at the transcriptional or protein level. Kupffer cells from BDL mice produced low levels of IL-12p40 and high levels of IL-10 in vitro in response to lipopolysaccharide derived from E. coli. In vivo administration of anti,IL-10 monoclonal antibody ameliorated the course of E. coli infection in BDL mice. Furthermore, BDL- lpr mice did not exhibit impairment in E. coli killing in association with little hepatic injury and a small amount of IL-10 production. In conclusion, increased IL-10 and reciprocally suppressed IL-12 production by Kupffer cells are responsible for deteriorated resistance to bacterial infection in BDL mice. Fas-mediated hepatocyte apoptosis in cholestasis may be involved in the predominant IL-10 production by Kupffer cells. (HEPATOLOGY 2004;40:414,423.) [source] Immunological basis of the development of necrotic lesions following Mycobacterium avium infectionIMMUNOLOGY, Issue 4 2002Manuela Flórido Summary Normal C57BL/6 mice infected with 106 colony-forming units of a highly virulent strain of Mycobacterium avium developed a progressive infection characterized by loss of T cells from the tissues and infiltration with high numbers of heavily infected macrophages. In contrast, when C57BL/6 mice were infected with 102 colony-forming units of the same strain they retained T cells and T-cell reactivity in the tissues, and granulomas evolved into large masses that, at 4 months of infection, exhibited central necrosis. The development of these necrotic lesions did not occur in nude mice, nor in mice genetically deficient in CD4, interleukin-12 (IL-12) p40, interferon-, (IFN-,) and CD40 and were reduced in mice deficient in CD54 or IL-6. They were less numerous but bigger in mice deficient in IL-10 or the inducible nitric oxide synthase, correlating with the increased resistance to mycobacterial proliferation of these strains as compared to control mice. The appearance of necrosis was not affected in mice deficient in CD8,, T-cell receptor ,, tumour necrosis factor receptor p55, and perforin, nor was it affected in mice over-expressing bcl2. The appearance of necrosis could be prevented by administering antibodies specific for CD4, IL-12p40, or IFN-, from the second month of infection when organized granulomas were already found. Our results show that the immunological mediators involved in the induction of protective immunity are also major players in the immunopathology associated with mycobacteriosis. [source] Octenidine in root canal and dentine disinfection ex vivoINTERNATIONAL ENDODONTIC JOURNAL, Issue 11 2007L. Tandjung Abstract Aim, The aim of the present study was to investigate the antimicrobial activity of octenidine on Enterococcus faecalis ATCC 29212 in a dentine block model. Methodology, Fifty-six root segments of extracted human teeth were infected with E. faecalis for 4 weeks. Octenidine-phenoxyethanol gel (1 : 1) was applied for different timing: 1 min, 10 min, 7 days and in a different formula (1 : 3) for 10 min. Three samples were chosen for the group with placebo gel and for the group without infection (negative control). Dentine samples were collected, and the total count of bacteria and colony-forming units were determined. In addition, for controls and the 10 min group with 1 : 1 gel, the proportion of viable bacteria (PVB) was assessed. Results, Octenidine was particularly effective after incubation periods of 10 min and 7 days. The mean PVB decreased significantly from 57.2% to 5.7% after 10 min application. After 7 days, only one of 10 samples showed positive culture. Conclusion, The present study showed the effectiveness of octenidine against E. faecalis in dentine disinfection. Further laboratory and clinical studies are required. [source] Antimicrobial activity of varying concentrations of sodium hypochlorite on the endodontic microorganisms Actinomyces israelii, A. naeslundii, Candida albicans and Enterococcus faecalisINTERNATIONAL ENDODONTIC JOURNAL, Issue 7 2004C. E. Radcliffe Abstract Aim, To determine the resistance of microorganisms associated with refractory endodontic infections to sodium hypochlorite used as a root canal irrigant. Methodology, Two strains each of Actinomyces naeslundii, Candida albicans and Enterococcus faecalis were tested as late logarithmic phase inocula, against sodium hypochlorite adjusted to 0.5, 1.0, 2.5 and 5.25% w/v. Contact times used were 0, 10, 20, 30, 60 and 120 s. In the case of E. faecalis, additional experiments used contact times of 1.0, 2.0, 5.0, 10.0 and 30.0 min. Anti-microbial action was halted by sodium thiosulphate addition. Survivors were measured primarily using viable counts on drop plates. Additionally, pour plates were used to count low colony-forming units (cfu) and dilutions to 10,6 were used to count high cfu. Results, All concentrations of NaOCl lowered cfu below the limit of detection after 10 s in the case of A. naeslundii and C. albicans. However, E. faecalis proved to be more resistant to NaOCl. Using 0.5% NaOCl for 30 min reduced cfu to zero for both strains tested. This compares with 10 min for 1.0%, 5 min for 2.5% and 2 min for 5.25% (P < 0.001). Regression analysis for the dependent variable loge(count + 1) with loge(time + 1) and concentration as explanatory variables gave rise to a significant interaction between time and concentration (P < 0.001). Conclusion, The published association of E. faecalis with refractory endodontic infection may result, at least partially, from high resistance of this species to NaOCl. This does not appear to be the case with A. naeslundii or C. albicans. [source] In vitro antimicrobial effect of chlorhexidine-impregnated gutta percha points on Enterococcus faecalisINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2004J. N. Lui Abstract Aim, To evaluate the in vitro antimicrobial effect of chlorhexidine-impregnated gutta percha points, Roeko activ point (Roeko, Langenau, Germany) on Enterococcus faecalis. Methodology, Human maxillary premolar roots were prepared with .04 rotary ProFile instruments to a master apical file size 40, autoclave-sterilized and then infected with E. faecalis (ATCC 29212) for 3 weeks. Baseline controls were carried out verifying negligible effects of plain gutta percha cones on E. faecalis. Subsequent to intracanal placement of calcium hydroxide, ,activ points' or saline (positive control) and the 2-week incubation in 54 root specimens, dentine sampling at depths of 100 and 250 µm was carried out using .04 rotary ProFile instruments at sizes 60 and 90 to assess the quantity of bacteria present. Inactivating agents were used prior to sampling and the colony-forming units (CFU) of E. faecalis were then plate-counted after culturing. Statistical analysis was completed using the paired t -test. Results, In comparison to the positive control, treatment with calcium hydroxide (P = 0.000 and 0.000) or activ points (P = 0.000 and 0.002) produced significantly lower colony counts of E. faecalis at dentine depths of 100 and 250 µm, respectively. Calcium hydroxide (2.10 × 102 CFU mL,1) was significantly more effective than activ points (1.58 × 103 CFU mL,1) at 100 µm (P = 0.013), but not at 250 µm (P = 0.353). Neither of these two medications was able to eliminate E. faecalis completely. Conclusions, Chlorhexidine-impregnated activ points did not possess an in vitro inhibitory activity strong enough to eliminate E. faecalis completely from infected dentinal tubules. [source] Chemical composition and microbial evaluation of Argentinean Corrientes cheeseINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 3 2008OLGA M VASEK The chemical and microbial composition of an artisanal cheese made from raw cow's milk produced and consumed in the province of Corrientes (north-eastern Argentina) was evaluated using standard methods. Corrientes cheese has high moisture content (50,60%), normal protein and fat contents (21,27 and 22,26% respectively), and is low in salt (0.5,2.0% w/w). Microbial counts also varied significantly between samples (colony-forming units per gram ranges covering logs of 5,11), probably due to environmental contamination in the raw material. These results will help produce higher quality Corrientes cheeses with well-defined characteristics. [source] A novel approach to controlling bacterial contamination on toothbrushes: chlorhexidine coatingINTERNATIONAL JOURNAL OF DENTAL HYGIENE, Issue 4 2009LA Turner Abstract:, Purpose:, This project was conducted to determine the effectiveness of chlorhexidine-coated toothbrush filaments in reducing quantities of bacteria. Materials and methods:, An Institutional Review Board (IRB)-approved, two-group, double-blind, randomized, post-test only study was conducted. Sixty-four individuals utilized control and experimental toothbrushes, for 30 days. At the end of the study toothbrushes were returned and transported to the laboratory for analysis. Microorganisms were detached from the filaments by sonification and vortexing then plated on Mitis Salivarius (MS) (selective) and trypticase soy agar (TSA) 5% Sheep Blood (non-selective) media. Inoculated plates were incubated aerobically for 24 h at 37°C. After incubation, bacterial colony-forming units (CFU) were determined. Data were analysed using Wilcoxon and Kruskal,Wallis tests. Results:, Fifty-nine toothbrushes were returned for analysis; experimental (n = 31) and control (n = 28). Data from TSA media revealed a mean CFU for the control group of 5.41 × 105 compared with 6.28 × 105 for the experimental group. Data from MS agar resulted in a mean CFU for the control group of 4.32 × 105 compared with 4.20 × 105 for the experimental group. Conclusion:, Results revealed no statistically significant difference in the quantity of bacteria surviving on toothbrush filaments between control and experimental groups, on both selective and non-selective media, after 30 days. [source] Experimental respiratory anthrax infection in the common marmoset (Callithrix jacchus)INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 3 2008Mark S. Lever Summary Inhalational anthrax is a rare but potentially fatal infection in man. The common marmoset (Callithrix jacchus) was evaluated as a small non-human primate (NHP) model of inhalational anthrax infection, as an alternative to larger NHP species. The marmoset was found to be susceptible to inhalational exposure to Bacillus anthracis Ames strain. The pathophysiology of infection following inhalational exposure was similar to that previously reported in the rhesus and cynomolgus macaque and humans. The calculated LD50 for B. anthracis Ames strain in the marmoset was 1.47 × 103 colony-forming units, compared with a published LD50 of 5.5 × 104 spores in the rhesus macaque and 4.13 × 103 spores in the cynomolgus macaque. This suggests that the common marmoset is an appropriate alternative NHP and will be used for the evaluation of medical countermeasures against respiratory anthrax infection. [source] Collection of peripheral blood stem cells with granulocyte-colony-stimulating factor alone in testicular cancer patientsINTERNATIONAL JOURNAL OF UROLOGY, Issue 3 2000KISABURO HANAZAWA Abstract Background: High-dose chemotherapy with the transplantation of peripheral blood stem cells (PBSC) has been performed for the treatment of advanced testicular cancer patients. Recently, it has been reported that, in healthy donors, a large quantity of stem cells can be transferred to peripheral blood using granulocyte-colony-stimulating factor (G-CSF) alone. Therefore, it was decided to try to harvest PBSC from three patients having testicular cancers with G-CSF alone. Methods: The three patients with testicular cancer were 26, 56 and 62-years-old. They had undergone five, two and three cycles of chemotherapy, respectively, but no radiation therapy. Granulocyte colony-stimulating factor was subcutaneously injected (250 ,g) into each patient twice per day for 6 days. Peripheral blood stem cells were harvested for 3 days (days 4,6) and mononuclear cells (MNC), CD34-positive cells and colony-forming units of granulocyte-macrophage (CFU-GM) in PBSC collected by apheresis were measured. Results: Apheresis showed that the total MNC count was 20.2 × 108/kg (range, 10.6,25.9 × 108/kg), the CD34-positive cell count was 0.98 × 106/kg (range, 0.75,1.4 × 106/kg) and the total CFU-GM count was 1.36 × 105/kg (range, 0.25,3.0 × 105/kg). Conclusion: After mobilization of peripheral blood stem cells with G-CSF alone, sufficient amounts of MNC were obtained from testicular cancer patients who had undergone chemotherapy several times. However, sufficient amounts of CD34-positive cells and CFU-GM could not be obtained. These results suggested that the G-CSF dose was not adequate for harvesting sufficient amounts of CD34-positive cells and CFU-GM. [source] In vitro studies on the effects of Saccharomyces boulardii and Bacillus cereus var. toyoi on nutrient transport in pig jejunumJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1-2 2000G. Breves The probiotics Saccharomyces boulardii and Bacillus cereus var. toyoi are nonpathogenic microbes which have been shown to affect certain functions of the mucosal barrier in pig jejunum such as electrogenic ion transport capacity and paracellular permeability. The present studies were performed to investigate potential effects of the probiotics on jejunal nutrient transport such as sodium-dependent glucose transport or proton-dependent dipeptide transport. For this purpose the in vitro Ussing-chamber technique was applied in order to examine net electrogenic ion flux rates (short circuit currents, Isc) across isolated intact jejunal epithelia in the absence and presence of either 10 mmol/l glucose (mucosal side) or two-fold application of 5 mmol/l glycyl- l -sarcosine or glycyl- l -glutamine to the mucosal bathing solution. Brush border membrane vesicles (BBMV) were prepared in order to characterize kinetic parameters (Vmax, Km) of Na-dependent glucose transport. Intestinal tissues were obtained from growing pigs in a weight range between 23 and 33 kg. All animals were fed twice daily and received 0.8,0.9 kg/day of a standard diet. After a 9- to 10-day adaptation period the diets for treated animals were either supplemented for 8 days with 1.7×107 colony-forming units (CFU)/g feed of S. boulardii or for 3 weeks with 106 CFU/g feed B. cereus var. toyoi. Under basal conditions Isc values were not affected by different treatment protocols (controls: 0.74 ± 0.04 µeq/cm2 per h, n=9; S. boulardii: 0.74 ± 0.12 µeq/cm2 per h, n=7; B. cereus 0.68 ± 0.09 µeq/cm2 per h, n=5). Irrespective of dietary treatment, the addition of glucose resulted in significant increases of Isc indicating substantial onset of electrogenic net Na/glucose cotransport. Maximal Isc values occurred within 30 min and reached 2.79 ± 0.41 µeq/cm2 per h in control epithelia. This was significantly lower than found in S. boulardii (4.47 ± 0.43 µeq/cm2 per h, p < 0.05) and B. cereus var. toyoi tissues (4.45 ± 0.31 µeq/cm2 per h, p < 0.05). Gt values were 22.4 ± 1.3 mS/cm2 in control animals and were significantly lower as shown in S. boulardii (p < 0.01) and B. cereus var. toyoi (p < 0.01)-treated animals (28.4 ± 1.3 and 29.9 ± 0.8 mS/cm2, respectively). Vmax values of Na-dependent glucose uptake into BBMV differed significantly between controls (0.64 ± 0.08 nmol/mg protein per 10 s; n=5), S. boulardii (0.89 ± 0.06 nmol/mg protein per 10 s; n=5, p < 0.05) and B. cereus var. toyoi preparations (1.08 ± 0.05 nmol/mg protein per 10 s; n=3, p < 0.01). Km values were not significantly affected (control: 0.31 ± 0.04 mmol/l, S. boulardii: 0.29 ± 0.05 mmol/l, B. cereus var. toyoi: 0.21 ± 0.01 mmol/l). Irrespective of dietary treatment, application of the dipeptide model substances glycyl- l -sarcosine or glycyl- l -glutamine resulted in significant increases of Isc indicating marked stimulation of electrogenic net H+/dipeptide cotransport. Highest Isc responses occurred in B. cereus var. toyoi preparations and lowest were found in control tissues. However, these differences were not significant. Gt values were not affected by different dietary treatments. The results clearly demonstrate that oral administration of either S. boulardii or B. cereus var. toyoi stimulates Na-dependent glucose absorption in pig jejunum. [source] Identification of surface protective antigen (spa) types in Erysipelothrix reference strains and diagnostic samples by spa multiplex real-time and conventional PCR assaysJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2010H.G. Shen Abstract Aim:, To develop spa multiplex real-time and conventional PCR assays to detect and differentiate between spaA, spaB and spaC genes within Erysipelothrix spp. Methods and Results:, For evaluation of the assays, 28 Erysipelothrix spp. reference strains, 25 tissues from pigs inoculated with reference strains of serotypes 1, 2, 5, 10 or 18, and 15 diagnostic samples were used. SpaA was found to be present in Erysipelothrix rhusiopathiae serotypes 1a, 1b, 2, 5, 9, 12, 15, 16, 17, 23 and N; spaB was detected in E. rhusiopathiae serotypes 4, 6, 8, 11, 19 and 21 and spaC was detected in E. sp. strain 2 serotype 18. Spa-related genes were not detected in E. tonsillarum strains (serotypes 3, 7, 10, 14, 20, 22, 24, 25, 26) or E. sp. strain 1 (serotype 13). With the spa multiplex real-time PCR assay, it was also possible to further differentiate spaB into spaB1 (serotypes 4, 6, 8, 19 and 21) and spaB2 (serotype 11). Overall, spaA was detected in seven experimental tissue samples and six diagnostic tissue samples, and spaC in two experimental tissue samples. The detection limits were determined to be five colony-forming units (CFU) per reaction for the spa multiplex real-time PCR assay and 4000 CFU per reaction for the conventional PCR assay. Conclusions:, Both spa PCR assays were specific and reproducible in the identification of spa types in Erysipelothrix spp. Significance and Impact of the Study:, The described spa PCR assays may be useful tools for investigating spa prevalence among strains isolated from field tissues and to determine the role of the Spa proteins in vaccine protection and pathogenesis. [source] The use of a quantitative real-time polymerase chain reaction assay for identification and enumeration of Lactobacillus buchneri in silageJOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2008R.J. Schmidt Abstract Aims:, To detect and quantify Lactobacillus buchneri in plant samples with the aid of polymerase chain reaction (PCR) methods. Methods and Results:, DNA from silage samples spiked with different amounts of L. buchneri cells was isolated using a lysozyme/sodium dodecyl sulfate lysis and phenol/chloroform extraction method. The DNA served as a template for PCR amplification with primers specific for the bacterium. The primers were developed by comparison of 16S rDNA sequences from different lactic acid bacteria (LAB) and testing for specificity with 11 different strains of LAB. As few as 100 L. buchneri colony-forming units per gram of silage could be detected. Additionally, the technique was successfully applied to quantify the population of L. buchneri in two cultivars of corn with or without inoculation. Conclusions:, The PCR assay provided a specific and rapid tool for identifying and enumerating L. buchneri in silage samples. Significance and Impact of the Study:, The use of microbial inoculants for silage production is a safe and environment friendly practice, but the full potential of such additives can only be achieved with a better understanding of the fate and activity of the microbes involved. The current study describes a methodology to detect and enumerate L. buchneri, a micro-organism used as an inoculant. [source] Microbiological status of piggery effluent from 13 piggeries in the south east Queensland region of AustraliaJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2004H.N. Chinivasagam Abstract Aims:, To assist in the development of safe piggery effluent re-use guidelines by determining the level of selected pathogens and indicator organisms in the effluent ponds of 13 south-east Queensland piggeries. Methods and Results:, The numbers of thermotolerant coliforms, Campylobacter jejuni/coli, Erysipelothrix rhusiopathiae, Escherichia coli, Salmonella and rotavirus were determined in 29 samples derived from the 13 piggeries. The study demonstrated that the 13 final effluent ponds contained an average of 1·2 × 105 colony-forming units (CFU) 100 ml,1 of thermotolerant coliforms and 1·03 × 105 CFU 100 ml,1 of E. coli. The Campylobacter level varied from none detectable (two of 13 piggeries) to a maximum of 930 most probable number (MPN) 100 ml,1 (two of 13 piggeries). Salmonella was detected in the final ponds of only four of the 13 piggeries and then only at a low level (highest level being 51 MPN 100 ml,1). No rotavirus and no Erysip. rhusiopathiae were detected. The average log10 reductions across the ponding systems to the final irrigation pond were 1·77 for thermotolerant coliforms, 1·71 for E. coli and 1·04 for Campylobacter. Conclusions:, This study has provided a baseline knowledge on the levels of indicator organisms and selected pathogens in piggery effluent. Significance and Impact of the Study:, The knowledge gained in this study will assist in the development of guidelines to ensure the safe and sustainable re-use of piggery effluent. [source] | ||||||||||||||||||||||||||||||||||||||||