Critical Step (critical + step)

Distribution by Scientific Domains
Distribution within Life Sciences


Selected Abstracts


Bacterial population dynamics and community structure in a pharmaceutical manufacturing water supply system determined by real-time PCR and PCR-denaturing gradient gel electrophoresis

JOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2004
M. Kawai
Abstract Aims:, To control bacteria in the pharmaceutical water supply system. Methods and Results:, Bacteria were enumerated by conventional culture method and fluorescent vital staining. Activated carbon treatment and storage in a tank provided favourable environments for bacterial growth. The bacterial population of the water in both the post-activated carbon treatment and the tank was analysed by denaturing gradient gel electrophoresis (DGGE) with PCR-amplified 16S rDNA fragments including V6, -7, and -8 regions. The bacterial community structure in activated carbon treated water was stable throughout the year. Several kinds of bacteria such as genus Aquaspirillum and Methylobacterium were found in the water after activated carbon treatment. The bacterial community structure was changed and other bacteria such as mycobacteria were detected after storage. Mycobacteria were quantified in water samples using real-time PCR targeting the 16S rDNA gene. Mycobacteria were also detected in tap water and their number was increased 103,104 -fold higher after storage. Conclusion:, These data suggest the importance of culture-independent methods for quality control of water used in pharmaceutical manufacturing. Significance and Impact of the Study:, Critical steps and specified bacteria that should be controlled in the water supply system were recognized by culture-independent methods. These data will enable effective control of water used in the pharmaceutical industry. [source]


Building a strong foundation for occupational health and safety: Action research in the workplace

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 8 2009
Judith A. Daltuva MSW
Abstract Background Action research (AR) holds promise as a method to improve occupational health and safety. Methods This case study explores the challenges and accomplishments during the first 6 months of an AR occupational health and safety committee at a manufacturing facility. Results Critical steps in the formative phase of the AR project included: (1) addressing differing power levels and perceived ownership of management and production committee members; (2) developing a collaborative approach to communication and problem solving; and (3) transitioning from dependence on university leadership to shared leadership among the committee. Conclusions AR can lead to greater empowerment to address occupational health and safety issues, and to improved dialoge between labor and management. AR can increase the likelihood that the problem will be understood, and effective solutions will be developed and their application supported and used throughout the organization. Am. J. Ind. Med. 52:614,624, 2009. © 2009 Wiley-Liss, Inc. [source]


Multiparameter immunophenotyping by flow cytometry in multiple myeloma: The diagnostic utility of defining ranges of normal antigenic expression in comparison to histology,

CYTOMETRY, Issue 4 2010
Elisa Cannizzo
Abstract Background: Numerous studies have reported on the immunophenotype of plasma cells (PCs) in monoclonal gammopathy of undetermined significance (MGUS) and in plasma cell myeloma (PCM), but very few have examined the immunophenotype of normal PCs. In this study, an objective definition of normal range of expression for each antigen was found on normal control PCs. Using these new ranges of normal expression (new method) is different from using a static 20% of PCs cut-off for all antigens as described in the literature (traditional method). These newly calculated normal ranges for each antigen were applied to our data, and compared to histologic and immunohistochemical findings. Methods: Bone marrow samples from 46 patients with PC neoplasms and 15 normal controls were studied. A minimum of 100 PC were analyzed for each patient and control sample. An 8-color staining method was applied to study the immunophenotype of PCs, using a BD FACSCanto II. Results: By the new ranges of normality calculated in this study it was determined that different antigens have different level of expression on polyclonal PCs. CD19 correlated with histology by both the traditional and new methods, but had superior correlation by the new method. Conclusions: This report is the first 8-color immunophenotypic study of PCM in which a "range of normal expression" for each antigen is defined. This is a critical step to help distinguish between a normal and neoplastic PC immunophenotype and discern which antigens are of diagnostic importance. © 2010 Clinical Cytometry Society [source]


Transgenic analysis of the medaka mesp-b enhancer in somitogenesis

DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 3 2006
Harumi Terasaki
Somitogenesis is a critical step during the formation of metameric structures in vertebrates. Recent studies in mouse, chick, zebrafish and Xenopus have revealed that several factors, such as T-box genes, Notch/Delta, Wnt, retinoic acid and FGF signaling, are involved in the specification of nascent somites. By interacting with these pathways, the Mesp2-like bHLH transcription factors are transiently expressed in the anterior presomitic mesoderm and play a crucial role in somite formation. The regulatory mechanisms of Mesp2 and its related genes during somitogenesis have been studied in mouse and Xenopus. However, the precise mechanism that regulates the transcriptional activity of Mesp2 has yet to be determined. In our current report, we identify the essential enhancer element of medaka mesp-b, an orthologue of mouse Mesp2, using transgenic techniques and embryo manipulation. Our results demonstrate that a region of approximately 2.8 kb, upstream of the mesp-b gene, is responsible for both the initiation and anterior localization of mesp-b transcription within a somite primordium. Furthermore, putative motifs for both T-box transcription factors and Notch/Delta signaling are present in this enhancer region and are essential for activity. [source]


Identification of candidate secreted factors involved in trigeminal placode induction

DEVELOPMENTAL DYNAMICS, Issue 10 2007
Kathryn L. McCabe
Abstract Cranial ectodermal placodes are critical for normal development of the peripheral nervous system of the head. However, many aspects of the molecular and tissue interactions involved in their induction have yet to be elucidated. The trigeminal placode is induced by an unidentified secreted factor(s) from the dorsal neural tube. To determine candidates that may be involved in this induction process, we have performed reverse transcriptase-polymerase chain reaction (RT-PCR) and whole-mount in situ hybridization to screen for receptors expressed by uninduced presumptive trigeminal level ectoderm. We have found that receptors for fibroblast growth factors, insulin-like growth factors, platelet-derived growth factors, Sonic hedgehog, the transforming growth factor-beta superfamily, and Wnts all are expressed in patterns consistent with a role in trigeminal placode formation. This RT-PCR screen for candidate receptors expressed in presumptive trigeminal ectoderm is the first systematic screen to identify potential interactions underlying induction of the trigeminal placode and represents a critical step for understanding this complex process. Developmental Dynamics 236:2925,2935, 2007. © 2007 Wiley-Liss, Inc. [source]


Frontal nasal prominence expression driven by Tcfap2a relies on a conserved binding site for STAT proteins

DEVELOPMENTAL DYNAMICS, Issue 5 2006
Amy L. Donner
Abstract The AP-2 transcription factor family is linked with development of the head and limbs in both vertebrate and invertebrate species. Recent evidence has also implicated this gene family in the evolution of the neural crest in chordates, a critical step that allowed the development and elaboration of the vertebrate craniofacial skeleton. In mice, the inappropriate embryonic expression of one particular AP-2 gene, Tcfap2a, encoding AP-2,, results in multiple developmental abnormalities, including craniofacial and limb defects. Thus, Tcfap2a provides a valuable genetic resource to analyze the regulatory hierarchy responsible for the evolution and development of the face and limbs. Previous studies have identified a 2-kilobase intronic region of both the mouse and human AP-2, locus that directs expression of a linked LacZ transgene to the facial processes and the distal mesenchyme of the limb bud in transgenic mice. Further analysis identified two highly conserved regions of ,200,400 bp within this tissue-specific enhancer. We have now initiated a transgenic and biochemical analysis of the most important of these highly conserved regions. Our analysis indicates that although the sequences regulating face and limb expression have been integrated into a single enhancer, different cis -acting sequences ultimately control these two expression domains. Moreover, these studies demonstrate that a conserved STAT binding site provides a major contribution to the expression of Tcfap2a in the facial prominences. Developmental Dynamics 235:1358,1370, 2006. © 2006 Wiley-Liss, Inc. [source]


A critical step for postsynaptic F-actin organization: Regulation of Baz/Par-3 localization by aPKC and PTEN

DEVELOPMENTAL NEUROBIOLOGY, Issue 9 2009
Preethi Ramachandran
Abstract Actin remodeling has emerged as a critical process during synapse development and plasticity. Thus, understanding the regulatory mechanisms controlling actin organization at synapses is exceedingly important. Here, we used the highly plastic Drosophila neuromuscular junction (NMJ) to understand mechanisms of actin remodeling at postsynaptic sites. Previous studies have suggested that the actin-binding proteins Spectrin and Coracle play a critical role in NMJ development and the anchoring of glutamate receptors most likely through actin regulation. Here, we show that an additional determinant of actin organization at the postsynaptic region is the PDZ protein Baz/Par-3. Decreasing Baz levels in postsynaptic muscles has dramatic consequences for the size of F-actin and spectrin domains at the postsynaptic region. In turn, proper localization of Baz at this site depends on both phosphorylation and dephosphorylation events. Baz phosphorylation by its binding partner, atypical protein kinase C (aPKC), is required for normal Baz targeting to the postsynaptic region. However, the retention of Baz at this site depends on its dephosphorylation mediated by the lipid and protein phosphatase PTEN. Misregulation of the phosphorylation state of Baz by genetic alterations in PTEN or aPKC activity has detrimental consequences for postsynaptic F-actin and spectrin localization, synaptic growth, and receptor localization. Our results provide a novel mechanism of postsynaptic actin regulation through Baz, governed by the antagonistic actions of aPKC and PTEN. Given the conservation of these proteins from worms to mammals, these results are likely to provide new insight into actin organization pathways. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source]


Genome-wide P -element screen for Drosophila synaptogenesis mutants

DEVELOPMENTAL NEUROBIOLOGY, Issue 4 2006
Faith L.W. Liebl
Abstract A molecular understanding of synaptogenesis is a critical step toward the goal of understanding how brains "wire themselves up," and then "rewire" during development and experience. Recent genomic and molecular advances have made it possible to study synaptogenesis on a genomic scale. Here, we describe the results of a screen for genes involved in formation and development of the glutamatergic Drosophila neuromuscular junction (NMJ). We screened 2185 P -element transposon mutants representing insertions in ,16% of the entire Drosophila genome. We first identified recessive lethal mutants, based on the hypothesis that mutations causing severe disruptions in synaptogenesis are likely to be lethal. Two hundred twenty (10%) of all insertions were homozygous lethal. Two hundred five (93%) of these lethal mutants developed at least through late embryogenesis and formed neuromusculature. We examined embryonic/larval NMJs in 202 of these homozygous mutants using immunocytochemistry and confocal microscopy. We identified and classified 88 mutants with altered NMJ morphology. Insertion loci in these mutants encode several different types of proteins, including ATP- and GTPases, cytoskeletal regulators, cell adhesion molecules, kinases, phosphatases, RNA regulators, regulators of protein formation, transcription factors, and transporters. Thirteen percent of insertions are in genes that encode proteins of novel or unknown function. Complementation tests and RT-PCR assays suggest that approximately 51% of the insertion lines carry background mutations. Our results reveal that synaptogenesis requires the coordinated action of many different types of proteins,perhaps as much as 44% of the entire genome,and that transposon mutageneses carry important caveats that must be respected when interpreting results generated using this method. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source]


The merging of community ecology and phylogenetic biology

ECOLOGY LETTERS, Issue 7 2009
Jeannine Cavender-Bares
Abstract The increasing availability of phylogenetic data, computing power and informatics tools has facilitated a rapid expansion of studies that apply phylogenetic data and methods to community ecology. Several key areas are reviewed in which phylogenetic information helps to resolve long-standing controversies in community ecology, challenges previous assumptions, and opens new areas of investigation. In particular, studies in phylogenetic community ecology have helped to reveal the multitude of processes driving community assembly and have demonstrated the importance of evolution in the assembly process. Phylogenetic approaches have also increased understanding of the consequences of community interactions for speciation, adaptation and extinction. Finally, phylogenetic community structure and composition holds promise for predicting ecosystem processes and impacts of global change. Major challenges to advancing these areas remain. In particular, determining the extent to which ecologically relevant traits are phylogenetically conserved or convergent, and over what temporal scale, is critical to understanding the causes of community phylogenetic structure and its evolutionary and ecosystem consequences. Harnessing phylogenetic information to understand and forecast changes in diversity and dynamics of communities is a critical step in managing and restoring the Earth's biota in a time of rapid global change. [source]


On-line cell lysis and DNA extraction on a microfluidic biochip fabricated by microelectromechanical system technology

ELECTROPHORESIS, Issue 9 2008
Xing Chen Dr.
Abstract Integrating cell lysis and DNA purification process into a micrototal analytical system (,TAS) is one critical step for the analysis of nucleic acids. On-chip cell lysis based on a chemical method is realized by sufficient blend of blood sample and the lyzing reagent. In this paper two mixing models, T-type mixing model and sandwich-type mixing model, are proposed and simulation of those models is conducted. Result of simulation shows that the sandwich-type mixing model with coiled channel performs best and this model is further used to construct the microfluidic biochip for on-line cell lysis and DNA extraction. The result of simulation is further verified by experiments. It asserts that more than 80% mixing of blood sample and lyzing reagent which guarantees that completed cell lysis can be achieved near the inlet location when the cell/buffer velocity ratio is less than 1:5. After cell lysis, DNA extraction by means of a solid-phase method is implemented by using porous silicon matrix which is integrated in the biochip. During continuous flow process in the microchip, rapid cell lysis and PCR-amplifiable genomic DNA purification can be achieved within 20,min. The potential of this microfluidic biochip is illustrated by pretreating a whole blood sample, which shows the possibility of integration of sample preparation, PCR, and separation on a single device to work as portable point-of-care medical diagnostic system. [source]


Abundances of crenarchaeal amoA genes and transcripts in the Pacific Ocean

ENVIRONMENTAL MICROBIOLOGY, Issue 3 2010
Matthew J. Church
Summary Planktonic Crenarchaea are thought to play a key role in chemolithotrophic ammonia oxidation, a critical step of the marine nitrogen (N) cycle. In this study, we examined the spatial distributions of ammonia-oxidizing Crenarchaea across a large (,5200 km) region of the central Pacific Ocean. Examination of crenarchaeal 16S rRNA, ammonia monooxygenase subunit A (amoA) genes, and amoA transcript abundances provided insight into their spatial distributions and activities. Crenarchaeal gene abundances increased three to four orders of magnitude with depth between the upper ocean waters and dimly lit waters of the mesopelagic zone. The resulting median value of the crenarchaeal amoA: 16S rRNA gene ratio was 1.3, suggesting the majority of Crenarchaea in the epi- and mesopelagic regions of the Pacific Ocean have the metabolic machinery for ammonia oxidation. Crenarchaeal amoA transcript abundances typically increased one to two orders of magnitude in the transitional zone separating the epipelagic waters from the mesopelagic (100,200 m), before decreasing into the interior of the mesopelagic zone. The resulting gene copy normalized transcript abundances revealed elevated amoA expression in the upper ocean waters (0,100 m) where crenarchaeal abundances were low, with transcripts decreasing into the mesopelagic zone as crenarchaeal gene abundances increased. These results suggest ammonia-oxidizing Crenarchaea are active contributors to the N cycle throughout the epi- and mesopelagic waters of the Pacific Ocean. [source]


Fluorescence in situ hybridization (FISH) analysis of the interactions between honeybee larvae and Paenibacillus larvae, the causative agent of American foulbrood of honeybees (Apis mellifera)

ENVIRONMENTAL MICROBIOLOGY, Issue 6 2008
Dominique Yue
Summary American foulbrood (AFB) is a bacterial disease of honeybee larvae caused by the spore-forming bacterium Paenibacillus larvae. Although AFB and its aetiological agent are described now for more than a century, the general and molecular pathogenesis of this notifiable disease is poorly understood. We used fluorescence in situ hybridization (FISH) performed with P. larvae -specific, 16S rRNA-targeted oligonucleotide probes to analyse the early steps in the pathogenesis of American foulbrood. The following chain of events could be demonstrated: (i) the spores germinate in the midgut lumen, (ii) the vegetative bacteria massively proliferate within the midgut before, and (iii) they start to locally breach the epithelium and invade the haemocoel. The paracellular route was shown to be the main mechanism for invasion contrasting earlier hypotheses of phagocytosis of P. larvae. Invasion coincided with the death of the host implicating that the penetration of the midgut epithelium is a critical step determining the time of death. [source]


Changes in microbial community composition following treatment of methanogenic granules with chloroform

ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 1 2009
Bo Hu
Abstract Eliminating hydrogen consuming bacteria is a critical step in anaerobic fermentation for biohydrogen production. Treatment of anaerobic granular sludge with chloroform was reported as effective in transforming a methane-producing system into a hydrogen-producing system by eliminating methane production. This study, using 16S rRNA gene sequences, further assessed changes in microbial community composition as a result of chloroform treatment and during continuous cultivation of chloroform-treated granules in a continuous upflow reactor employing immobilized cells. Profiles of terminal restriction fragment length polymorphisms (T-RFLP) of 16S rRNA genes sequences cloned from samples before and after chloroform treatment showed that methanogenic hydrogen consumers and Methanosaeta harundinacea sp. were eliminated. Methanosaeta concilii, however, was not eliminated from the hydrogen-producing system, which might explain, in part, the granulation phenomena in the anaerobic hydrogen fermentation system. The results also showed that Clostridium butyricum dominated the hydrogen-production system. © 2009 American Institute of Chemical Engineers Environ Prog, 2009 [source]


From organisms to populations: Modeling aquatic toxicity data across two levels of biological organization

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2006
Sandy Raimondo
Abstract A critical step in estimating the ecological effects of a toxicant is extrapolating organism-level response data across higher levels of biological organization. In the present study, the organism-to-population link is made for the mysid, Americamysis bahia, exposed to a range of concentrations of six toxicants. Organism-level responses observed were categorized as no effect, delayed reproduction, reduced overall reproduction, or both reduced overall reproduction and survival. Population multiplication rates of each toxicant concentration were obtained from matrix models developed from organism-level endpoints and placed into the four categories of organism-level responses. Rates within each category were compared with growth rates modeled for control populations. Population multiplication rates were significantly less than control growth rates only for concentrations at which overall reproduction and both reproduction and survival were significantly less than the control values on the organism level. Decomposition analysis of the significant population-level effects identified reduced reproduction as the primary contributor to a reduced population multiplication rate at all sublethal concentrations and most lethal concentrations. Mortality was the primary contributor to reduced population growth rate only when survival was less than 25% of control survival. These results suggest the importance of altered reproduction in population-level risk assessment and emphasizes the need for complete life-cycle test data to make an explicit link between the organism and population levels. [source]


Complete elimination of carbonates: A critical step in the accurate measurement of organic and black carbon in sediments

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2005
Marta T. Lukasewycz
Abstract Accurate measurement of organic carbon (OC) and black carbon (BC) in sediments requires the complete removal of coexisting inorganic carbonates from the sample before instrumental analysis. The removal of carbonates from sediments is achieved with acidification, which causes the dissolution and decomposition of carbonates with accompanying effervescence. This effervescence, or the lack of it, is commonly used as an indicator for the presence or absence of carbonates. We have found that the lack of effervescence endpoint used with the direct acidification method (adding aliquots of acid to samples) is not a reliable indicator for complete removal of carbonates from sediment samples. The ineffectiveness of the lack of effervescence endpoint, we believe, is caused by the presence of carbonates with dissolution rates much slower than those of calcite, resulting in much slower rates of visible effervescence. We propose and demonstrate a method for determining the amount of acid required for complete elimination of all carbonates using Lake Michigan (USA) sediment samples. Based on our experiences with the lack of effervescence endpoint, we recommend that in any scheme for analysis of OC and/or BC, a minimum of two samples be treated with three different levels of acidification, with the lowest level being the same as that planned for all the OC and/or BC analyses. There can be no significant differences among the OC and BC contents measured using the three different levels of acidification. [source]


Echistatin inhibits pp125FAK autophosphorylation, paxillin phosphorylation and pp125FAK,paxillin interaction in fibronectin-adherent melanoma cells

FEBS JOURNAL, Issue 16 2000
Rossella Della Morte
Echistatin, a snake-venom RGD-containing protein, was previously shown to disrupt cell-matrix adhesion by a mechanism that involves the reduction of pp125FAK tyrosine phosphorylation levels. The aim of this study was to establish the sequence of events downstream pp125FAK dephosphorylation that could be responsible for echistatin-induced disassembly of actin cytoskeleton and focal adhesions in fibronectin-adherent B16-BL6 melanoma cells. The results obtained show that echistatin induces a decrease of both autophosphorylation and kinase activity of pp125FAK. One hour of cell exposure to echistatin caused a 39% decrease of pp125FAK Tyr397 phosphorylation and a 31% reduction of pp125FAK autophosphorylation activity as measured by immune-complex kinase assay. Furthermore, 1 h of cell treatment by echistatin produced a 63% decrease of paxillin phosphorylation, as well as a reduction in the amount of paxillin bound to pp125FAK. Immunofluorescence analysis of echistatin treated cells showed the concomitant disappearance of both paxillin and pp125FAK from focal adhesions. The reduction of paxillin phosphorylation may represent a critical step in the pathway by which disintegrins exert their biological activity, including the inhibition of experimental metastasis in vivo. [source]


hScrib, a human homologue of Drosophila neoplastic tumor suppressor, is a novel death substrate targeted by caspase during the process of apoptosis

GENES TO CELLS, Issue 7 2008
Kenbun Sone
hScrib, human homologue of Drosophila neoplastic tumor suppressor, was identified as a target of human papillomavirus E6 oncoprotein for the ubiquitin-mediated degradation. Here, we report that hScrib is a novel death substrate targeted by caspase. Full-length hScrib was cleaved by caspase during death ligands-induced apoptosis, which generates a p170 C-terminal fragments in Hela cells. In vitro cleavage assay using recombinant caspases showed that hScrib is cleaved by the executioner caspases. DNA damage-induced apoptosis caused loss of expression of full-length hScrib, which was recovered by addition of capase-3 inhibitor in HaCat cells. TUNEL positive apoptotic cells, which were identified 4 h after UV irradiation in HaCat cells, showed loss of hScrib expression at the adherens junction. Mutational analysis identified the caspase-dependent cleavage site of hScrib at the position of Asp-504. Although MDCK cells transfected with GFP-fused wild-type hScrib showed loss of E-cadherin expression and shrinkage of cytoplasm by UV irradiation, cells transfected with hScrib with Ala substitution of Asp-504 showed resistance to caspase-dependent cleavage of hScrib and intact expression of E-cadherin. These results indicate that caspase-dependent cleavage of hScrib is a critical step for detachment of cell contact during the process of apoptosis. [source]


Use of dry powder inhalers in COPD

INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 12 2007
D. S. Wilson
Summary Introduction:, This was a study of 30 chronic obstructive pulmonary disease (COPD) patients to assess the ease of use and preference of four dry powder inhalers , accuhaler, aerolizer, handihaler, turbohaler , the accuhaler and turbohaler are multidose devices, whereas the aerolizer and handihaler are single dose devices. Method:, None of the subjects had previous experience of dry powder inhalers. The correct technique for each inhaler was divided into 12 steps including one critical step that if not performed would result in no drug delivery. Subjects were shown the correct technique for each inhaler in a random order and were assessed immediately and 1 h later. Each subject was asked to rank the four devices for preference and ease of use, as well as to assess how comfortable it felt to inhale through the device using a visual analogue scale. Results:, The numbers of perfect scores were not significantly different between devices, but the number of fatal errors that would result in no drug delivery was significantly more common in single dose devices (p < 0.01). There were significant differences in the rankings of each device (Friedman test, p < 0.005) with the turbohaler being ranked first most often and the handihaler last. The turbohaler scored highest for comfort of inhalation and the accuhaler lowest, but differences were small. Conclusions:, In COPD patients starting on dry powder inhalers, multidose devices appear to be preferred, have fewer problems and are easier to use effectively. [source]


Public Action, Agrarian Change and the Standard of Living of Agricultural Workers: A Study of a Village in Kerala

JOURNAL OF AGRARIAN CHANGE, Issue 3 2006
R. RAMAKUMAR
This article describes and analyses the ways in which public action in the State of Kerala in India helped to transform the standard of living of hired workers in agriculture. Specifically, the article analyses the extent of land and asset ownership, access to credit, access to social security schemes and food distribution systems and the conditions of housing and sanitation of households participating in agricultural wage work. The article is based as a case study of Morazha desam in the Malabar region of Kerala, which had one of the most oppressive agrarian systems in India before 1956,57. In 1955, another economist had studied Morazha desam; this study was conducted before one of the most important interventions through public action , land reform , took place in Malabar. The 1955 study had characterized the conditions of life of agricultural workers as ,wretched in the extreme'. The present article documents the significant transformation in the quality of life that took place in Morazha after 1955, through a weakening of the factors that led to ,wretched' conditions of life in the earlier period. The destruction of traditional agrarian power by the state through land reform was the most critical step in this process. [source]


Do Rural Elders Have Limited Access to Medicare Hospice Services?

JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 5 2004
Beth A. Virnig PhD
Objectives:, To examine whether there are urban-rural differences in use of the Medicare hospice benefit before death and whether those differences suggest that there is a problem with access to hospice care for rural Medicare beneficiaries. Design:, Observational study using 100% of Medicare enrollment, hospice, and hospital claims data. Setting:, Inpatient hospitals and hospices. Participants:, Persons aged 65 and older in the Medicare program who died in 1999. Measurements:, Rates of hospice use before death and in-hospital death rates were calculated. Results:, In 1999, there were 1.76 million deaths of Medicare beneficiaries aged 65 and older. Hospice services were used by 365,700 of these beneficiaries. Rates of hospice care before death were negatively associated with degree of rurality. The lowest rate of hospice use, 15.2% of deaths, was seen in rural areas not adjacent to an urban area. The highest rate of use, 22.2% of deaths, was seen in urban areas. Rural areas adjacent to urban areas had an intermediate level of hospice use (17.0% of deaths). Hospices based in rural areas had a smaller number of elderly patients each year than hospices based in urban areas (P<.001) and were more likely to have very low volumes (average daily census of three patients or less). Conclusion:, The consistently lower use of Medicare hospice services before death and smaller sizes of rural hospices suggest that the combination of Medicare hospice payment policies and hospice volumes are problematic for rural hospices. Adjusting Medicare payment policies might be a critical step to assure availability of hospice services forterminally ill beneficiaries regardless of where they live. [source]


Automated concentration and recovery of micro-organisms from drinking water using dead-end ultrafiltration

JOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2008
E.A. Kearns
Abstract Aims:, Concentration of pathogens diluted in large volumes of water is necessary for their detection. An automated concentration system placed online in drinking water distribution systems would facilitate detection and mitigate the risk to public health. Methods and Results:, A prototype concentrator based on dead-end hollow fibre ultrafiltration was used to concentrate Bacillus atrophaeus spores directly from tap water. Backflush was used to recover accumulated particulates for analysis. In field tests conducted on a water utility distribution system, 3·2 × 104,1·4 × 106 CFU ml,1 (6·1 × 106,3·0 × 108 CFU) were recovered from the filter when 2·9 × 107,1·0 × 109 CFU were spiked into the system. Per cent recovery ranged from 21% to 68% for flow volumes of 15,21 l. Tests using spore influent levels <10 CFU l,1 (spike < 1000 CFU) yielded 23,40% recovery for volumes >100 l. Conclusions:,B. atrophaeus spores at levels <10 CFU l,1 were concentrated directly from tap water using an automated dead-end hollow-fibre ultrafiltration system. Significance and Impact of the Study:, The prototype concentrator represents a critical step towards an autonomous system that could be installed in drinking water distribution lines or other critical water lines to facilitate monitoring. Recovered samples can be analysed using standard or rapid biosensor methods. [source]


Achieving hygiene in the domestic kitchen: the effectiveness of commonly used cleaning procedures

JOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2002
T.A. Cogan
Aims:,To quantify the transmission of Salmonella and Campylobacter to hands, cloths, and hand- and food-contact surfaces during the preparation of raw poultry in domestic kitchens, and to examine the impact on numbers of these bacteria of detergent-based cleaning alone, or in conjunction with thorough rising. Methods and Results:,Groups of volunteers prepared chickens for cooking. Surfaces were sampled either before cleaning or after cleaning using water and detergent with or without thorough rinsing. Although cleaning followed by rinsing consistently achieved decontamination of surfaces contaminated with Campylobacter, significant numbers of surfaces were still contaminated with low numbers of Salmonella. Where cloths contaminated with Salmonella were stored overnight, a reduction in the efficacy of detergent-based cleaning regimes was observed. Conclusions:,Rinsing is the critical step in ensuring that bacteria are removed from surfaces during cleaning, but this may still leave residual contamination. Growth of Salmonella occurs in some contaminated cloths during overnight storage; Salmonella on cloths stored overnight are also more difficult to remove by washing. Significance and Impact of the Study:,Rinsing, as part of the cleaning process, is a critical step in achieving hygiene in the kitchen. However, to achieve completely hygienic surfaces, the use of an antimicrobial agent may be necessary. [source]


Study of saline wastewater influence on activated sludge flocs through automated image analysis

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 4 2009
Daniela P Mesquita
Abstract BACKGROUND: In activated sludge systems, sludge settling ability is considered a critical step in effluent quality and determinant of solid,liquid separation processes. However, few studies have reported the influence of saline wastewater on activated sludge. This work aims the evaluation of settling ability properties of microbial aggregates in a sequencing batch reactor treating saline wastewaters of up to 60 g L,1 NaCl, by image analysis procedures. RESULTS: It was found that the sludge volume index (SVI) decreased with salt content up to 20 g L,1, remaining somewhat stable above this value. Furthermore, it was found that between the first salt concentration (5 g L,1) and 20 g L,1 aggregates suffered a strong deflocculation phenomenon, leading to a heavy loss of aggregated biomass. Regarding SVI prediction ability, a good correlation coefficient of 0.991 between observed and predicted SVI values was attained. CONCLUSION: From this work the deflocculation of aggregated biomass with salt addition due to pinpoint floc formation, dispersed bacteria growth and protozoa absence could be established. With respect to SVI estimation, and despite the good correlation obtained, caution is advisable given the low number of SVI data points. Copyright © 2008 Society of Chemical Industry [source]


PHYSICOCHEMICAL AND FLAVOR CHANGES OF FRAGRANT BANANA (MUSA ACUMINATA AAA GROUP "GROSS MICHEL") DURING RIPENING

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2010
SOMRUEDEE THAIPHANIT
ABSTRACT The objective of this research was to characterize the physicochemical and flavor changes that occur in ripe Hom Thong (Musa acuminata AAA Group "Gross Michel") flesh at stage 6,8. It was found that the higher fresh maturity stage of Hom Thong at P < 0.05 has the following results: the antioxidant activities, moisture content and reducing sugar are significantly increased. The titratable acidity, total soluble solid and prebiotic activities' score for Lactobacillus acidophilus LA5 and Bifidobacterium lactis BB-12 are significantly decreased. The total dietary fiber remains unchanged. Using headspace solid-phase microextraction and gas chromatography,mass spectrometry to characterize volatile compound found that the flavor 20 volatile compounds (11 esters, 5 alcohols, 3 carbonyls and 1 ketone) are varied on Hom Thong maturity stage. The compounds with the most aroma impact for ripe Hom Thong flesh at stage 6,8 were 3-methylbutyl butanoate, 3-methyl-1-butyl acetate, 3-methylbutyl 3-methylbutanoate and 2-methylpropyl ethanoate. PRACTICAL APPLICATIONS Ripe banana Musa acuminata, AAA Group "Gross Michel," locally known in Thailand as Hom Thong, is a popular food item consumed as fruit, snacks or food ingredients for confections, spreads and other banana products. Using a suitable ripening stage of the banana flesh is the most critical step among many steps of unit operations for achieving high-quality banana products. This study not only characterizes the physicochemical and flavor changes that occur in ripe Hom Thong flesh at stage 6,8, but also studies antioxidant activities and prebiotic activities. Manufacturers can utilize the data presented in this article to select the suitable ripening stage in order to avoid product failure and to produce the best quality products for functional food, pharmafood, medifood or vitafood that are rich in natural banana flavor. [source]


OPTIMAL COAGULANT CONCENTRATION, SOYMILK AND TOFU QUALITY AS AFFECTED BY A SHORT-TERM MODEL STORAGE OF PROTO SOYBEANS

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 1 2008
ZHI-SHENG LIU
ABSTRACT Soybeans were adjusted to water activities (Aw) from 0.60 to 0.81, and stored at 30C for up to 3 months. At 1-month intervals, soybeans were retrieved from the storage and processed into 10.5 Brix soymilk. The optimal coagulant concentration (OCC) for making filled tofu was determined using a titration method. Other soymilk characteristics, including total solids, protein, 11 S/7 S protein ratio, phytate, titratable acidity, pH and color, were also determined. Filled tofu was prepared from each stored soybeans with the respective OCC using MgCl2 or CaCl2. With increasing Aw or storage time, the OCC decreased significantly. The decrease in OCC was significantly correlated to the difference in soymilk titratable acidity and the change in soymilk pH. Soybean storage time slightly decreased the breaking stress and apparent Young's modulus of the filled tofu, particularly the MgCl2 coagulated tofu. With increasing Aw or storage time, the lightness and yellowness intensity of both soymilk and tofu decreased, whereas their redness intensity increased. PRACTICAL APPLICATIONS Tofu and soymilk are popular soybean foods. Using optimal concentration of coagulant in soymilk is the most critical step among many steps of unit operations during tofu manufacturing for achieving high quality tofu. Improper use of coagulant can lead to product failure and therefore significant economic loss for the manufacturers. The optimal coagulant concentration varies not only with processing condition, but also with soybean materials which are affected by variety and storage conditions. Acidity, pH and food color are important quality factors to influence taste and consumer acceptance. Soybeans are subject to storage and transportation before processing. Storage length and environmental humidity are two of important factors which affect soybean quality and processing property. This study provides very important information that is useful for the soymilk and tofu manufacturers in controlling product quality through the understanding of the chemistry and processing characteristics of stored soybeans. Manufacturers can utilize the methods presented in this article to calculate the optimal coagulant concentrations to avoid product failure and to produce the best quality products. [source]


Genetic Analyses of Meiotic Recombination in Arabidopsis

JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 8 2007
Asela J. Wijeratne
Abstract Meiosis is essential for sexual reproduction and recombination is a critical step required for normal meiosis. Understanding the underlying molecular mechanisms that regulate recombination is important for medical, agricultural and ecological reasons. Readily available molecular and cytological tools make Arabidopsis an excellent system to study meiosis. Here we review recent developments in molecular genetic analyses on meiotic recombination. These include studies on plant homologs of yeast and animal genes, as well as novel genes that were first identified in plants. The characterizations of these genes have demonstrated essential functions from the initiation of recombination by double-strand breaks to repair of such breaks, from the formation of double-Holliday junctions to possible resolution of these junctions, both of which are critical for crossover formation. The recent advances have ushered a new era in plant meiosis, in which the combination of genetics, genomics, and molecular cytology can uncover important gene functions. [source]


Transforming growth factor ,1 (TGF,1) expression in head and neck squamous cell carcinoma patients as related to prognosis

JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 3 2003
Angela F. Logullo
Abstract Background:, Transforming growth factor ,1 (TGF,1) is a negative growth regulator in keratinocytes, and in vitro studies lead to the concept that loss of TGF,1 responsiveness is a critical step in epithelial carcinogenesis. Objective:, To investigate the prognostic relevance of TGF,1 expression in head and neck squamous cell carcinoma (HNSCC). Materials and methods:, TGF,1 distribution was determined by immunohistochemistry in oral cavity/oropharynx (n = 79), larynx (n = 36) and hypopharynx (n = 25) tumors and in matched normal adjacent mucosa. TGF,-type I and II receptors were determined in 20 cases of differentiated oral cavity/hypopharynx tumors. Cases were considered positive if displaying reactivity in >10% of the cells. Results:, TGF,1-positive expression was found in 47.2% of larynx, 36.7% of oral cavity/oropharynx and in 24% of the hypopharynx tumors. Reactivity in >60% of the cells was displayed only by 11.4% of HNSCC. All normal controls were positive. TGF,1-positive expression did not correlate with clinico pathological parameters. An association with differentiation was verified only in oral cavity/oropharynx tumors (P , 0.001). TGF,1 was also not related to 5 years survival (Kaplan,Meier). Strong and diffuse expression of TGF,-RII was identified in 19/20 cases regardless of TGF,1 immunoreactivity. Out of 17 TGF,1-positive oral cavity/oropharynx tumors, only nine expressed TGF,-RI suggesting a disruption of the TGF,1 pathway. We conclude that TGF,1 protein immunostaining is not a useful biomarker in assessment of prognosis in HNSCC. [source]


Molecular Identification of Phytophthora spp.

JOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2009
Affecting some Economically Important Crops in Eastern India through ITS-RFLP, Sequencing of the ITS Region
Abstract Molecular identification of the Phytophthora spp. affecting betelvine (Piper betel), brinjal (Solanum melongena), guava (Psidium guajava), roselle (Hibiscus subdariffa), black pepper (Piper nigrum), sesame (Sesamum indicum), taro (Colocasia esculenta), chilli (Capsicum annuum), pointed gourd (Trichosanthes dioica), papaya (Carica papaya) was performed through rDNA ITS-RFLP and also additionally by sequencing the Internal Transcriber spacer (ITS) ITS1 and ITS2 regions. Phytophthora nicotianae, Phytophthora capsici, Phytophthora colocasiae, Phytophthora melonis and Phytophthora palmivora isolates from these 10 different crops were accessioned and the ITS sequences were deposited in Genbank. ITS sequences for Phytophthora isolates from most of these crops are being reported here for the first time. In this study, a review of all earlier Indian reports based on morphology from the above crops and their molecular corroboration has been attempted. This study revealed that not only is P. nicotianae the most prevalent species but also there is the presence of both P. nicotianae and P. capsici, but not P. palmivora on betelvine; as well as possible first reports of P. nicotianae on pepper, P. capsici on chilli and P. palmivora on papaya from this vegetable growing Eastern region of the country. Mating type assays and RAPD markers were used to assess the genotypic diversity of the population. This detection of diversity is a first and critical step for helping to devise and adopt strategies for control and quarantine of these pathogens in this region. [source]


The effects of vasoactive agents, platelet agonists and anticoagulation on thrombelastography

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2007
J. Kawasaki
Background:, Platelet activation is a critical step in primary hemostasis and clot formation. We tested a hypothesis that platelet stimulating effects of vasoactive agents or platelet agonists could be shown using thrombelastography (TEG®) as faster onset or increased clot strength. We further examined if TEG® could be modified to evaluate activated platelets as a reversal of anticoagulation in the presence of partial thrombin inhibition. Methods:, Blood samples were obtained from 126 non-cardiac surgical patients. Effects of vasoactive agents on TEG® and aggregometry were examined using epinephrine, norepinephrine, vasopressin, desmopressin acetate, milrinone and olprinone (Experiment I). Platelet agonists (epinephrine, ADP and collagen) were separately tested on TEG® (Experiment II). Effects of platelet agonists (ADP and collagen) on TEG® under anticoagulation in the absence or presence of abciximab were studied (Experiment III). We also tested antiplatelet effects of milrinone and olprinone in the presence of anticoagulants on TEG® (Experiment IV). Results:, Neither vasoactive agents nor platelet agonists affected TEG® or aggregometry results except for milrinone and olprinone on aggregometry (Experiment I, II). Platelet agonists facilitated clotting in the presence of anticoagulants (Experiment III). Abciximab-treated platelets still exhibited procoagulant effects in the presence of heparin, while not in the presence of argatroban (Experiment III). Platelet inhibition on the modified TEG® was more extensive with milrinone than olprinone, and it was dose dependent (Experiment IV). Conclusion:, Modified TEG® using heparin or argatroban might delineate the procoagulant effects of platelets by adding platelet specific agonist. [source]


Age-dependent vascular endothelial growth factor expression and angiogenic capability of bladder smooth muscle cells: implications for cell-seeded technology in bladder tissue engineering

JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 8 2009
Joseph Azzarello
Abstract Cell seeding technology is commonly used in the field of tissue engineering to enhance the performance of bioscaffolds and promote tissue regeneration. The age of cells used for ex vivo seeding to achieve maximal tissue regeneration has not been defined. Since rapid angiogenesis is the most critical step for tissue graft survival and success, we evaluated passage-dependent vascular endothelial growth factor (VEGF) expression in cultured smooth muscle cells (SMCs) obtained from urinary bladder and endothelial cell response to bladder SMCs. Levels of various VEGF isoforms mRNA expression and total VEGF secretion were determined by a semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) and an enzyme-linked immunosorbent assay (ELISA) analysis, respectively. In vitro endothelial cell migration in Transwell® and capillary-like tube formation in MatrigelÔ were used to predict the ability of bladder SMCs to promote angiogenesis. VEGF produced by cultured bladder SMCs increased from passages 4 to 7, and decreased from passages 7 to 12 at both mRNA and protein levels. Endothelial cell migration as well as capillary-like tube formation correlated with levels of VEGF expression by bladder SMCs. Pre-incubation of endothelial cells with a VEGF receptor 1/2 inhibitor, SU5416, significantly reduced the number of capillary-like tubes in SMC-endothelial cell MatrigelÔ co-culture, and confirmed the involvement of VEGF in endothelial cell tube formation. Our results demonstrate that cell passage number is related to levels of VEGF production, which may translate to angiogenesis in engineered tissues. Copyright © 2009 John Wiley & Sons, Ltd. [source]