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Necrotic Tissue (necrotic + tissue)
Selected AbstractsHealing of Venous Ulcers of Long Duration with a Bilayered Living Skin Substitute: Results from a General Surgery and Dermatology DepartmentDERMATOLOGIC SURGERY, Issue 11 2001Harold Brem MD Background. A laboratory-grown bilayered living skin substitute (LSS) has been shown to accelerate the healing of venous ulcers. However, issues related to optimal wound bed preparation prior to the application of LSS have not been addressed. Objective. When combined with standard compression therapy and near elimination of wound exudate, bioengineered skin can achieve complete closure of venous ulcers which have been present for more than a year and which are difficult to heal. Methods. In the general surgery (center A) and dermatology (center B) departments at two separate medical centers, LSS was used to treat venous ulcers of more than 1 year's duration and which had been unresponsive to conventional therapy. Wound bed preparation at both centers had as common goals the removal of necrotic tissue, optimal formation of granulation tissue, and elimination of wound exudate. Results. There was great comparability between the two centers in the patients being treated, wound size and duration, and number of LSS applications. Both centers achieved a frequency of complete wound closure of greater than 70% within 6 months. Conclusion. At two separate clinical and specialty sites having a common goal of optimal wound preparation, treatment with LSS was associated with a high rate of complete closure of hard to heal venous ulcers. [source] Early diagnosis of rhinocerebral mucormycosis by cerebrospinal fluid analysis and determination of 16s rRNA gene sequenceEUROPEAN JOURNAL OF NEUROLOGY, Issue 9 2007D. Bengel A 40-year-old diabetic woman was diagnosed with rhinocerebral mucormycosis. Cerebral mucormycosis is an acute life-threatening disease, which is caused by fungi of the class Phycomycetae. Clinical suspicion and detection of the fungal hyphae in cerebrospinal fluid (CSF) led to early diagnosis, subsequently confirmed by immunohistochemistry and molecular analysis of fungal RNA. Early infiltration of the infectious agent into the central nervous system resulted in septic thrombosis of the cavernous sinus, mycotic meningoencephalitis, brain infarctions as well as intracerebral and subarachnoidal hemorrhages. Despite immediate high-dose antimycotic treatment, surgical debridement of necrotic tissue, and control of diabetes as a predisposing factor, the woman died 2 weeks after admission. Although fungal organisms are rarely detectable in CSF specimens from patients with mycotic infections of the central nervous system, comprehensive CSF examination is beneficial in the diagnosis of rhinocerebral mucormycosis. Furthermore, a concerted team approach, systemic antifungal agents and early surgical intervention seem to be crucial for preventing rapid disease progression. [source] Sclerotinia sclerotiorum: When "to be or not to be" a pathogen?FEMS MICROBIOLOGY LETTERS, Issue 2 2005Dwayne D. Hegedus Abstract Sclerotinia sclerotiorum is unusual among necrotrophic pathogens in its requirement for senescent tissues to establish an infection and to complete the life cycle. A model for the infection process has emerged whereby the pathogenic phase is bounded by saprophytic phases; the distinction being that the dead tissues in the latter are generated by the actions of the pathogen. Initial colonization of dead tissue provides nutrients for pathogen establishment and resources to infect healthy plant tissue. The early pathogenicity stage involves production of oxalic acid and the expression of cell wall degrading enzymes, such as specific isoforms of polygalacturonase (SSPG1) and protease (ASPS), at the expanding edge of the lesion. Such activities release small molecules (oligo-galacturonides and peptides) that serve to induce the expression of a second wave of degradative enzymes that collectively bring about the total dissolution of the plant tissue. Oxalic acid and other metabolites and enzymes suppress host defences during the pathogenic phase, while other components initiate host cell death responses leading to the formation of necrotic tissue. The pathogenic phase is followed by a second saprophytic phase, the transition to which is effected by declining cAMP levels as glucose becomes available and further hydrolytic enzyme synthesis is repressed. Low cAMP levels and an acidic environment generated by the secretion of oxalic acid promote sclerotial development and completion of the life cycle. This review brings together histological, biochemical and molecular information gathered over the past several decades to develop this tri-phasic model for infection. In several instances, studies with Botrytis species are drawn upon for supplemental and supportive evidence for this model. In this process, we attempt to outline how the interplay between glucose levels, cAMP and ambient pH serves to coordinate the transition between these phases and dictate the biochemical and developmental events that define them. [source] Cervical spondylodiscitis: A rare complication after phonatory prosthesis insertionHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 1 2006Andrea Bolzoni MD Abstract Background. Tracheoesophageal puncture has excellent voice rehabilitation after total laryngectomy. However, despite its easy insertion and use, severe complications have been reported. Methods. We report a case of cervical spondylodiscitis, occurring in a 67-year-old woman submitted to phonatory prosthesis insertion. After 1 month, she complained of severe cervicalgia associated with fever. Spondylodiscitis involving C6, C7, and the intervening vertebral disk with medullary compression was detected by means of imaging studies. Results. A right cervicotomy with drainage of necrotic tissue was performed, and a deepithelialized fasciocutaneous deltopectoral flap was interposed between the neopharynx-esophagus and the prevertebral fascia to protect the neurovascular axis. MR performed 1 month later showed a complete resolution of the infectious process. Conclusions. Severe neck pain after tracheoesophageal puncture should alert the physician about the possibility of a cervical spondylodiscitis. MR is the most useful imaging technique for preoperative and postoperative evaluation. When neurologic symptoms are detected, surgical exploration of the neck is mandatory. © 2005 Wiley Periodicals, Inc. Head Neck28: XXX,XXX, 2005 [source] The successful use of maggots in necrotizing fasciitis of the neck: A case reportHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 8 2004Simon F. Preuss MD Abstract Background. The use of maggots to digest necrotic tissue as a form of wound debridement has a long history in medicine. Necrotizing fasciitis of the neck has a high mortality rate despite aggressive surgical and medical intervention. The use of maggots in this disease has been reported only once before. Methods. We report the case of a 73-year-old woman, who underwent neck dissection and had necrotizing fasciitis of the neck develop shortly after. After initial surgical wound debridement, we used maggots as a biosurgical method for further debridement. A net containing 100 maggots (Biobag; BioMonde, Germany) was used. Results. Daily wound dressing showed rapid improvement of the wound; 4 days after beginning treatment, the wound was free of necroses. Conclusion. In this case, we could avoid repeated surgical wound debridement with the use of sterile maggots. The frequently rapid progression of necrotizing fasciitis could be well controlled. © 2004 Wiley Periodicals, Inc. Head Neck26: 747,750, 2004 [source] Current status of minimally invasive necrosectomy for post-inflammatory pancreatic necrosisHPB, Issue 2 2009Benoy Idicula Babu Abstract Objective:, This paper reviews current knowledge on minimally invasive pancreatic necrosectomy. Background:, Blunt (non-anatomical) debridement of necrotic tissue at laparotomy is the standard method of treatment of infected post-inflammatory pancreatic necrosis. Recognition that laparotomy may add to morbidity by increasing postoperative organ dysfunction has led to the development of alternative, minimally invasive methods for debridement. This study reports the status of minimally invasive necrosectomy by different approaches. Methods:, Searches of MEDLINE and EMBASE for the period 1996,2008 were undertaken. Only studies with original data and information on outcome were included. This produced a final population of 28 studies reporting on 344 patients undergoing minimally invasive necrosectomy, with a median (range) number of patients per study of nine (1,53). Procedures were categorized as retroperitoneal, endoscopic or laparoscopic. Results:, A total of 141 patients underwent retroperitoneal necrosectomy, of whom 58 (41%) had complications and 18 (13%) required laparotomy. There were 22 (16%) deaths. Overall, 157 patients underwent endoscopic necrosectomy; major complications were reported in 31 (20%) and death in seven (5%). Laparoscopic necrosectomy was carried out in 46 patients, of whom five (11%) required laparotomy and three (7%) died. Conclusions:, Minimally invasive necrosectomy is technically feasible and a body of evidence now suggests that acceptable outcomes can be achieved. There are no comparisons of results, either with open surgery or among different minimally invasive techniques. [source] Pyoderma gangrenosum of the scalp treated with cyclosporine AINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 12 2002Pasquale Patrone MD A 56-year-old woman presented with an ulcer, with a depth of 9 mm, on the vertex and frontal parietal regions of the scalp. The lesion had a round shape (diameter, 7 cm), with clear-cut margins and vertical borders sinking vertically to a bottom that was entirely covered with purulent fibrinous yellowish matter and greenish colored necrotic tissue. Other numerous small roundish ulcers were present next to the large ulcer. These had irregular margins with a yellowish fibrinous bottom (Fig. 1). The patient reported the appearance of two small ulcers on the left and on the right frontal parietal regions about 1 year earlier. These had been treated locally with antimicrobials and antiseptics with no result. During the 2 months prior to our evaluation, a few small round-shaped ulcers had appeared on the scalp. These had progressively increased in size and number. Figure Figure 1 . Large ulcer with clear-cut margins, covered by purulent fibrinous matter, and other small roundish ulcers The patient had been an insulin-dependent diabetic for 23 years. Hematochemical examinations showed no significant alterations, except for a rise in glycemia. Urine examination gave normal results. Carcinoembryonic antigen and lymphocytic phenotyping indices were normal. Echographic, endoscopic, and radiocontrast studies of the abdomen did not reveal the presence of lesions either in the gastrointestinal tract or in other organs. Samples of ulcerous tissue were collected from the scalp to perform histologic and microbiologic analysis in search of fungi and bacteria. This last examination revealed the presence of Staphylococcus aureus and Candida parapsylosis. Direct search for mycobacteria was negative. Histology indicated the presence of dermal granulomatous inflammation with giant multinucleate cells, associated with large zones of suppuration and colliquative necrosis. While waiting to complete the diagnostic course, topical antiseptic, antimicrobial, and fibrinolytic therapy was administered; subsequently, as this did not lead to any improvement, systemic treatment with cyclosporine A (5 mg/kg/day) was started. Rapid improvement of the clinical picture occurred. The ulcers appeared cleaner from the first 2 weeks of treatment, radial growth stopped, and the margins were slightly more superficial. The patient continued with immunomodulating therapy at home over a period of 7 months. The dose was progressively reduced until, over a period of about 3 months, complete re-epithelialization of the lesion, with subsequent partial regrowth of the hair, was obtained (Figs 2 and 3). No relapses were observed 1 year after treatment was suspended. Figure 2. Partial re-epithelialization of the lesion with partial regrowth of the hair Figure 3. Scar and hair regrowth [source] Evaluation of the nano-oligosaccharide factor lipido-colloid matrix in the local management of venous leg ulcers: results of a randomised, controlled trialINTERNATIONAL WOUND JOURNAL, Issue 2 2008Jean-Luc Schmutz Abstract The nano-oligosaccharide factor (NOSF) is a new compound aiming to promote wound closure mainly through inhibition of matrix metalloproteinase (MMP) activity. This factor is incorporated within a lipido-colloid matrix (Techonology Lipido-Colloid-NOSF matrix) and locally released in the wound. The objective of this study was to document the performance (non inferiority or superiority) of the NOSF relative to the Promogran® matrix (oxidised regenerated cellulose, ORC) effect in the local management of venous leg ulcers (VLUs). This was a 12-week, open, two-arm, multicentre, randomised study. Patients were selected if the area of their VLU [ankle brachial pressure index ,0·80] ranged from 5 to 25 cm2 with a duration ,3 months. Ulcers had to be free from necrotic tissue. In addition to receiving compression bandage therapy, patients were randomly allocated to either NOSF matrix or ORC treatment for 12 weeks. The VLUs were assessed on a weekly basis and wound tracings were recorded. Percentage wound relative reduction (%RR) was the primary efficacy criterion. Secondary objectives were wound absolute reduction (AR), healing rate (HR) and % of wounds with ,40% reduction compared with baseline. A total of 117 patients were included (57 NOSF matrix and 60 ORC). Mean population age was 71·3 ± 13·5 years, body mass index was ,30 kg/m2 in 39·3% and 15·4% were diabetics. Fifty-six per cent of the VLUs were present for >6 months, 61% were recurrent and 68% were stagnating despite appropriate care. Mean wound area at baseline was 11·2 ± 7·4 cm2. At the last evaluation, mean difference between the groups for %RR was 33·6 ± 15·0% in favour of NOSF matrix with a unilateral 95% confidence interval (CI) lower limit of 8·6% not including the null value. Therefore, a superiority of NOSF matrix effect compared with ORC was concluded (P = 0·0059 for superiority test). The median of the wound area reduction was 61·1% and 7·7% in the NOSF matrix and control groups, respectively (per-protocol analysis), or 54·4% versus 12·9% in intent-to-treat analysis (p = 0·0286). Median AR was 4·2 cm2 in the NOSF group and 1·0 cm2 with ORC (P = 0·01). Median HR was ,0·056 and ,0·015 cm2/day in NOSF and ORC groups, respectively (P = 0·029). By logistic regression, the NOSF versus control odds ratio to reach 40% area reduction was 2·4 (95% CI: 1·1,5·3; P = 0·026). In the oldest and largest VLUs, a strong promotion of healing effect was particularly observed in the NOSF matrix group compared with the control group. NOSF matrix is a very promising option for the local management of chronic wounds, especially for VLUs with poor healing prognosis. [source] An approach to the management of necrotising fasciitis in neonatesINTERNATIONAL WOUND JOURNAL, Issue 2 2005Soraya Zuloaga-Salcedo MD Abstract Necrotising fasciitis is a severe, life-threatening soft tissue infection. It produces an extensive cellulitis with severe involvement of subcutaneous tissue, fascia, muscle or both, resulting in necrosis of the tissue. All age groups, including neonates, can be affected. Patients with necrotising fasciitis present with more severe constitutional symptoms and have a poor outcome, unless aggressive antibiotic therapy and surgical debridement are instituted promptly. The debridement of necrotic tissue is imperative to control the infection, but results in deep wounds that require further treatment. In this study, the neonate was treated with alginate dressings and negative pressure therapy after resolution of cellulitis, with excellent results and no untoward events. [source] Delineation of brain tumor margins using intraoperative sononavigation: Implications for tumor resectionJOURNAL OF CLINICAL ULTRASOUND, Issue 4 2006Nobusada Shinoura MD Abstract Purpose. Sonography has been employed for real-time intraoperative delineation of tumor boundaries during resection of brain tumors. However, the variably hyperechoic appearance of brain edema or gliosis surrounding the brain may interfere with accurate depiction of tumor margins. The goal of the present study was to use sononavigation, which provides coregistration between real-time sonograms and MRI scans, to assess the accuracy of sonographic determination of tumor margins. Methods. Sononavigation was performed on 12 brain tumors (7 metastatic brain tumors, 2 meningiomas, 1 anaplastic oligodendroglioma, 1 anaplastic pilocytic astrocytoma, and 1 anaplastic astrocytoma). Sonograms of tumor margins were categorized into 1 of 3 types: in type 1, the tumor margin was clearly visualized and corresponded to the margin of the enhanced lesion on MR scan in all areas; in type 2, the tumor margin was clearly seen in some areas but was obscure in others due to hyperechoic edema; and in type 3, the tumor margin was indistinguishable from surrounding tissues in all areas. Results. Three metastatic brain tumors and 1 meningioma were categorized as type 1. Three metastatic brain tumors, 1 meningioma, and 1 anaplastic oligodendroglioma were categorized as type 2. The anaplastic pilocytic astrocytoma, 1 metastatic brain tumor (which consisted mainly of necrotic tissue), and the anaplastic astrocytoma were categorized as type 3. These data assist in determining whether the sonographic appearance of tumor margins is accurate and whether to rely on information from either sonography (type 1) or the sononavigation system when resecting tumor types 1, 2, and 3. Conclusions. Sononavigation can help categorize the sonographic tumor margins into 3 different patterns, and this categorization can assist in determining which imaging modalities are needed to better delineate the tumor margins for subsequent resection. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:177,183, 2006 [source] Incidence, spectrum and antibiotic sensitivity pattern of bacterial infections among patients with acute pancreatitisJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 9 2001Pramod Kumar Garg Abstract Background and Aim: Secondary infection of pancreatic necrotic tissue and peripancreatic fluid is a serious complication of acute pancreatitis resulting in significant morbidity and mortality. The aim of this study was to find out the spectrum of bacterial infections, and their antibiotic sensitivity pattern in patients with acute pancreatitis. Methods: All consecutive patients with acute pancreatitis were studied prospectively. Detailed investigations were carried out to identify bacterial infections and their antibiotic sensitivities in patients with suspected infection. These investigations included cultures of various body fluids, throat swabs, indwelling cannula and catheter tips. Pancreatic tissue was obtained by using needle aspiration or at surgery for Gram's stain, culture and sensitivity. All cultures were repeated until the presence of infection was confirmed or excluded. Results: A total of 169 patients with acute pancreatitis were studied during the period between January 1997 and June 2000 (mean age 41.3 years; 116 males and 53 females). Of the 169 patients, 63 had infections at various sites. A total of 80 cultures were positive, and 12 different bacterial isolates were cultured from samples taken from these 63 patients. Polymicrobial infection was seen in 32% of patients. Twenty-four patients had a confirmed pancreatic infection. Blood cultures had a growth of organisms in 19 patients, with evidence of ongoing or worsening pancreatitis, thus raising a strong suspicion of infected necrosis in them. The commonest organisms were Escherichia coli from 20 cultures and Pseudomonas aeruginosa from 18 cultures. The antibiotic sensitivity pattern showed that most bacteria were sensitive to third generation cephalosporins and quinolones; notably among them were cefotaxime, ceftazidime, and ciprofloxacin. Conclusion: Bacterial infections were seen in 37% of patients with acute pancreatitis. The commonest organisms were Pseudomonas aeruginosa and Escherichia coli. Most bacterial isolates were sensitive to third generation cephalosporins and quinolones. [source] Synthesis and preliminary biological evaluation of a 99mTc-labeled hypericin derivative as a necrosis avid imaging agentJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 1 2008Humphrey Fonge Abstract Mono-[123I]iodohypericin and mono-[123I]iodohypericin monocarboxylic acid are iodine-123-labeled hypericin derivatives which have shown great promise in preclinical studies as necrosis avid imaging agents in animal models of infarction. In view of the more attractive properties of a 99mTc-labeled hypericin derivative, we have synthesized a conjugate of protohypericin monocarboxylic acid with S -benzoylmercaptoacetyldiglycyl-diaminopentane in an overall yield of 15%. The conjugate was labeled with technetium-99m by exchange labeling at pH 10 in a labeling yield of 95% followed by photocyclization to yield 99mTc-mercaptoacetyldiglycyl-1,5-diaminopentylene hypericincarboxamide (99mTc-13). The negatively charged 99mTc-13 complex was purified by reversed phase high-pressure liquid chromatography and the log,P7.4 was determined to be 2.36. In normal NMRI mice, the complex showed slow hepatobiliary clearance while plasma clearance was rapid. The tracer was evaluated in rats with reperfused hepatic infarction by ex vivo autoradiography, gamma counting and histochemical techniques. Unlike the radioiodinated hypericin derivatives, the new tracer agent did not show preferential uptake in necrotic tissue on autoradiography and gamma counting techniques. Conjugation of hypericin with a 99mTc-chelate, resulting in a change in size, charge and lipophilicity, had a profound effect on the necrosis avidity of the tracer agent. The results show that 99mTc-13 is not suitable for imaging necrosis. Copyright © 2008 John Wiley & Sons, Ltd. [source] Nitric oxide in wound-healingMICROSURGERY, Issue 5 2005Jeff S. Isenberg M.D., M.P.H. Modulation of the complex process of wound-healing remains a surgical challenge. Little improvement beyond controlling infection, gentle tissue handling, and debridement of necrotic tissue has been had in the modern era. However, increasing appreciation of the process from a biomolecular perspective offers the potential for making significant strides in wound modulation. The bioactive molecule nitric oxide was found to have wide-ranging impact on cellular activities, including the cellular responses engendered by wound healing. Current research suggests that nitric oxide and several nitric oxide donors can exert biologic effects, although the particular net responses of cells contributing to wound repair are context-dependent. © 2005 Wiley-Liss, Inc. Microsurgery 25:442,451, 2005. [source] Effects of some pharmacological agents on the survival of unipedicled venous flaps: an experimental studyMICROSURGERY, Issue 8 2001Ibrahim Askar M.D. Clinical and experimental studies have been conducted to improve the survival of venous flaps. As a result of these studies, although various survival mechanisms were raised, none obtained satisfactory information. Venous stasis, and the resultant venous thrombosis, is a factor that decreases the survival of venous flaps. In this study, we evaluated the effects of two antiinflammatory agents, etodolac and etofenamate, on the survival of unipedicled venous flaps. In this study, 35 male New Zealand white rabbits (3,500,4,000 g) (70 ears) were used. Perichondrocutaneous flaps, 3 × 4.5 cm in size, were designed and raised, keeping the central veins intact in the middle of venous flap. Central arteries and nerves were ligated and transected both proximally and distally, to prepare unipedicled venous flaps. A silicone sheet was placed between the cartilage tissue and flap, to prevent blood flow and revascularization beneath. The subjects were divided into seven groups, consisting of five rabbits (10 ears). In the negative control group (group I), the single vascular pedicle of venous flaps, central veins were ligated and flaps sutured into their own place as the composite graft. In the positive control group (group II), after venous flaps were prepared, normal saline, 0.2 mL, was given subcutaneously. In the first of five experimental groups (group III), unfractionated heparin (100 U/day) was given subcutaneously. In the second experimental group (group IV), etodolac (5 mg/kg/day) was given subcutaneously. In the third experimental group (group V), etophenamate (5 mg/kg/day) was given orally through a feeding tube. In the fourth experimental group (group VI), parnaparin (5 anti-Xa U/kg/day) was given subcutaneously. In the fifth experimental group (group VII), nadroparin (5 anti-Xa U/kg/day) was given subcutaneously, about 7 days postoperatively. At the eighth postoperative day, surviving areas of venous flaps were measured, and the results were evaluated by Kruskal-Wallis ANOVA and Mann-Whitney U-test (P < 0.05). Biopsies were also taken from the flaps for histological evaluation of border of necrotic tissue. Surviving areas of unipedicled venous flaps were larger in experimental groups than those in negative and positive control group (P < 0.05). However, comparison of the experimental groups demonstrated no statistically significant difference (P > 0.05). We concluded that all pharmacological agents used in the experimental groups succeeded in increasing the survival of unipedicled venous flaps. Survival of the unipedicled venous flap was higher in venous flaps than that of composite graft, clearly showing the importance of the venous pedicle. © 2001 Wiley-Liss Inc. MICROSURGERY 21:350--356, 2001 [source] Comparison of the Healing Mechanisms of Myocardial Lesions Induced by Dry Radiofrequency and Microwave Epicardial AblationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2006ROSA HENRIQUES DE GOUVEIA Background: Histological assessment of the evolution of lesions induced on a pig's left atrium by microwave (MW) epicardial applications and comparison with dry radiofrequency (RF) lesions. Methods: MW (40 W, 40 seconds) and dry RF (80°C, 2 minutes) were epicardially applied on nine pigs' left atrium. Samples were procured following application (n = 2), at day 3 (n = 2), day 7 (n = 2), day 14 (n = 2), and at 1 month (n = 1). They were fixed in formalin, embedded in paraffin, sectioned (2 ,), stained with histochemical dyes, immunomarked, and histologically analyzed. Results: Histological features of acute stage MW lesion are interstitial hemorrhage, adipose, and muscular tissues' coagulation necrosis, thrombosis of myocardial interstitium small vessels at damaged and optically undamaged areas, epicardial coronary branches, and endocardial parietal thrombosis. Day 3,lymphohistiocytic infiltration (lysosyme+) highlights lesion limits. Day 7,lymphohistiocytic infiltration increases, multi-nucleated giant cells appear surrounding/fagocyting necrotic tissue. Neovessels and scarce myofibroblasts appear. Lesion edges are now better defined. Day 14,myofibroblastic proliferation (actin++, vimentin+) creates "young" scar tissue, as in "healing by second intention." Lesions are deeper and wider than appeared at acute stage. One month,dense fibrous tissue scar appears. Endothelial cells covering endocardium are morphologically intact. RF lesions are histologically identical to MW's, although no vessel thrombosis was identified at acute optically undamaged areas and cytomorphologic elements emerge at later stages in the healing process. Conclusions: (1) Microwave scars are deeper and wider than the lesions observed at the acute stage. (2) Evolution of microwave lesions is faster and induces broader scars than dry radiofrequency. (3) Scar formation (both energies) is "healing by second intention." (4) Endocardial thrombosis may occur despite morphologically intact endothelium. [source] A dual infection by infectious cuticular epithelial necrosis virus and a Chlamydia -like organism in cultured Litopenaeus vannamei (Boone) in EcuadorAQUACULTURE RESEARCH, Issue 11 2001R Jimenez During 1996, microscopic examinations of post larvae and juveniles of moribund Litopenaeus vannamei showed multifocal necrosis in the cuticular epithelial tissues. In addition to these severe degenerative alterations in the epithelial cells typical of infectious cuticular epithelial necrosis virus (ICENV), columnar cells of the epithelium displayed small round intracytoplasmic inclusions in the necrotic tissue. Examination by electron microscopy of affected tissues demonstrated prokaryotic organisms in the cytoplasm of epithelial cells delineated by a distinct cytoplasmic vesicle; the prokaryotic organisms were morphologically similar to the genus Chlamydia. The necrotic tissue also showed the presence of particles of ICENV; the double infection by two different organisms in cuticular epithelial cells has not been reported previously. Two distinct stages in the intracellular development of a Chlamydia -like organism were recognized: (1) pleomorphic elementary bodies (EBs) that were spherical to oval were often observed in the process of division or in forming a common chain of three cells, the cells were surrounded by a rigid cell envelope and the presence of a cap or plaque hexagonally arrayed; (2) the reticular bodies (RBs) were forms often in the process of division. These cells had an electron-dense cytoplasm and contained a loose network of nuclear fibrils and a more fragile cell envelope. Regardless of the development stages of the Chlamydia -like organism within the cytoplasmic vesicles, ICENV particles were observed, either dispersed or in clusters, surrounded or inside the vesicles. The potential adverse impact of this dual infection on shrimp culture should be considered, especially in high-density operations. [source] Protective effects of plasmin(ogen) in a mouse model of Staphylococcus aureus,induced arthritisARTHRITIS & RHEUMATISM, Issue 3 2008Yongzhi Guo Objective To assess the functional roles of plasmin in a murine model of Staphylococcus aureus,induced bacterial arthritis. Methods Bacterial arthritis was induced in plasminogen-deficient (Plg,/,) and wild-type (Plg+/+) littermates by local injection of 1 × 106 colony-forming units of S aureus into the knee joints. Human plasminogen was administered to Plg,/, mice on days 0,7 or days 7,14. Antibiotic treatment was administered to Plg,/, mice on days 7,14. Bacteria counts and histologic, immunohistochemical, and Western blot analyses were performed. Results In Plg+/+ mice, S aureus counts had declined within 2 days, and by day 28 the bacteria had been completely eliminated. However, S aureus was still detectable in all injected joints from Plg,/, mice, and bacteria counts were 27 times higher than the amount injected on day 0. The extent of macrophage and neutrophil recruitment to the infected joints was comparable for Plg+/+ and Plg,/, mice on days 1, 7, and 14. The activation of these inflammatory cells appeared to be impaired in Plg,/, mice, however. Treatment of Plg,/, mice with antibiotic (cloxacillin) resulted in successful killing of the bacteria, but the necrotic tissue remained in the infected joints. When human plasminogen was given intravenously to Plg,/, mice daily for 7 days, bacterial clearance was greatly improved as compared with their untreated counterparts, and the amount of necrotic tissue in the joint cavity was dramatically reduced. The expression of interleukin 6 (IL-6) and IL-10 was higher in Plg+/+ mice than in Plg,/, mice during bacterial arthritis. Conclusion Our findings indicate that plasmin plays a pluripotent role in protecting against S aureus,induced arthritis by activating inflammatory cells, killing bacteria, removing necrotic tissue, and enhancing cytokine expression. [source] 70 vs 120 W thulium:yttrium-aluminium-garnet 2 µm continuous-wave laser for the treatment of benign prostatic hyperplasia: a systematic ex-vivo evaluationBJU INTERNATIONAL, Issue 3 2010Thorsten Bach Study Type , Aetiology (case series) Level of Evidence 4 OBJECTIVE To evaluate the ablative and haemostatic properties of the recently introduced 120-W thulium:yttrium-aluminium-garnet (Tm-YAG) laser and to assess these results against those of the previously introduced 70-W Tm-YAG laser. MATERIALS AND METHODS The ex-vivo model of the isolated blood-perfused porcine kidney was used to determine the ablation capacity, haemostatic properties and coagulation depth of a 2 µm continuous-wave Tm-YAG laser. The energy was delivered using a 550-µm and an 800-µm bare-ended fibre. The results of the recently introduced 120-W Tm-YAG were compared to the established 70-W device. Kidney tissue was embedded for histological evaluation. After staining (haematoxylin and eosin, H&E; and NADH) of the specimen, the coagulation zone and depth of the necrotic tissue layer were measured. RESULTS With increased power output, the mean (sd) rate of vaporization of tissue increased, from 9.80 (3.03) g/10 min at 70 W to 16.41 (5.2) g/10 min at 120 W using the 550 µm fibre. The total amount of ablated tissue using the 800 µm fibre was lower than with the 550 µm fibre. With increasing power output the bleeding rate remained stable in either group. Tissue penetration remained shallow, even with increasing power output. In contrast to H&E staining, where the coagulation zone was measured, NADH staining showed an inner zone of necrotic tissue, again with no difference between the 70- and the 120-W Tm-YAG. CONCLUSION The 120-W Tm-YAG offers significantly higher ablation rates than the 70-W device, and despite the increased rate of ablation with the 120-W Tm-YAG, the bleeding rate and depth of tissue penetration were comparable to those using the 70-W device. [source] Treatment of Candida infection in patients with infected pancreatic necrosisBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 7 2000G. Farkas Background The purpose of this review was to determine the incidence of Candida infection in patients with infected pancreatic necrosis, to determine the most frequent risk factors and to assess the best treatment approach for disseminated candidal infections. Methods Of 145 patients with infected pancreatic necrosis identified, 30 (21 per cent) were infected with C. albicans. Risk factors identified in patients with Candida infection included the presence of necrotic tissue, and the use of broad-spectrum antibiotics, intravascular catheters and parenteral nutrition. Results With one exception, all cases involved mixed bacterial and fungal infections. The positive fungal result was obtained either during or after operation. Sixteen of the 30 patients displayed fungal colonization, while the other 14 had disseminated fungal infection. There were two deaths in the disseminated group, but none in the colonization group. In both fatal cases, flucytosine was applied. When fluconazole was used against disseminated fungal infection, no death was noted. Recently, prophylactic fluconazole has also been used in 20 patients with infected pancreatic necrosis, with no evidence of fungal infection after operation. Conclusion The combination of adequate surgical treatment with effective antibiotics and early antifungal therapy is the ideal management approach for infected pancreatic necrosis with Candida infection. Fluconazole may be regarded as an efficient drug for the prophylaxis of candidiasis. © 2000 British Journal of Surgery Society Ltd [source] Larval therapy as a palliative treatment for severe arteriosclerotic gangrene on the feetCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 8 2009A. Nordström Summary Larval therapy (LT) is known to be a gentle and effective method for removing necrotic tissue and bacteria and reducing the accompanying unpleasant odour. Ischaemia has been considered a relative contraindication for LT. We report a patient with ischaemia treated with LT. Inguinal revascularization was performed on a 69-year-old man with critical limb ischaemia, diabetes mellitus, heart failure and end-stage renal disease. Areas of dry black malodorous gangrene remained on the distal areas of the feet after surgery and the patient's poor health did not allow any additional surgery. The patient was referred to the dermatology department for LT. Although patients are usually given this treatment as inpatients, the patient requested treatment at home. After the first LT, there was a marked reduction in odour. The gangrene needed repeated applications of larvae to remove the dead tissue. After eight treatments, the result was more positive than we had expected, with total lack of odour and initiation of healing. Larvae cannot penetrate eschar, thus free-range larvae were used because they can move beneath the hard necrotic tissue and dissolve it. [source] Resistance of Pinus contorta to the European race of Gremmeniella abietinaFOREST PATHOLOGY, Issue 2 2006G. Laflamme Summary Pinus contorta seedlings, together with Pinus resinosa and Pinus banksiana seedlings, were planted adjacent to 25-year-old red pine trees infected by the European (EU) race of Gremmeniella abietina. Resistance to this race was assessed over 5 years. All P. resinosa seedlings were dead after that period while 65% of P. contorta and 86% of P. banksiana seedlings appeared resistant to the disease. The tip blight that occurred on P. contorta was slightly longer than that observed on P. banksiana. In microscopy, one, two, or even more suberized boundaries were seen to be initiated near the surface of the shoot at the base of healthy needles where they extended downward in the direction of the vascular cambium. Suberized boundaries occasionally crossed the xylem and joined together in the pith region to form continuous barriers around necrotic tissues. However, in most cases, these suberized barriers were not continuous across the shoot and compartmentalization was then completed by other barriers mainly constituted of parenchyma cells and xylem tracheids that accumulated phenolic compounds. Meristematic-like cells were observed adjacent to the necrophylactic periderm. Tissue regeneration, restoration of cambial activities and formation of traumatic resin canals also seemed to be associated with the defence system of P. contorta against the EU race of G. abietina. Résumé Des semis de Pinus contorta, de P. resinosa et de P. banksiana ont été plantés près de pins rouges âgés de 25 ans et infectés par la race européenne (EU) de Gremmeniella abietina. La résistance à cette race a étéévaluée sur une période de 5 ans. Tous les semis de P. resinosa sont morts après cette période alors que 65% des semis de P. contorta et 86% des semis de P. banksiana semblaient résister à la maladie. La brûlure à l'extrémité des pousses sur le P. contortaétait un peu plus longue que celle observée sur le P. banksiana. En microscopie, une, deux et même plusieurs couches de cellules subérisées se sont différenciées près de la surface des pousses à la base d'aiguilles saines et continuaient à progresser basipétalement en direction du cambium. Ces couches subérisées traversaient occasionnellement le xylème avant de fusionner près de la moelle pour former des barrières continues autour des tissus nécrosés. Toutefois, dans la plupart des cas, les barrières subérisées présentes dans les pousses étaient discontinues et le compartimentage était alors complété par d'autres barrières constituées de cellules de parenchyme et de trachéides ayant accumulé des composés phénoliques. Des cellules semblables à celles présentes dans les zones méristématiques furent observées près du périderme nécrophylactique. La présence de nouveaux tissus, le rétablissement de l'activité cambiale et la formation de canaux résinifères traumatiques semblaient aussi contribuer au système de défense de P. contorta contre la souche EU de G. abietina. Zusammenfassung In der Nachbarschaft von 25jährigen Pinus resinosa, die mit der europäischen Rasse von Gremmeniella abietina infiziert waren, wurden Sämlinge von Pinus contorta zusammen mit Sämlingen von Pinus resinosa und Pinus banksiana ausgepflanzt. Während fünf Jahren wurde die Resistenz gegenüber dieser Erregerrasse beobachtet. Am Ende des Beobachtungszeitraums waren alle P. resinosa -Sämlinge tot, während 65% der P. contorta und 86% der P. banksiana -Sämlinge überlebten. Die Nekrosen an der Triebspitze waren auf P. contorta etwas länger als bei P. banksiana. Mikroskopisch waren ein, zwei oder sogar mehr suberinisierte Abwehrzonen erkennbar, deren Bildung nahe der Trieboberfläche an der Basis gesunder Nadeln begann und die sich nach unten in Richtung auf das Kambium ausdehnten. Gelegentlich entstanden diese suberinisierten Zonen auch im Xylem und vereinigten sich im Mark miteinander, so dass eine geschlossene Barriere gegen die nekrotischen Gewebe entstand. In den meisten Fällen dehnten sich die suberinisierten Zonen aber nicht durch den ganzen Trieb aus und die Kompartimentierung wurde durch andere Barrieren ergänzt, die vorwiegend aus parenchymatischen Zellen und Tracheiden bestanden, in denen phenolische Stoffe akkumuliert wurden. Neben dem nekrophylaktischen Periderm wurden Zellen mit meristematischer Aktivität beobachtet. Daneben waren die Neubildung von Geweben, die Wiederherstellung der Kambiumaktivität und die Bildung traumatischer Harzkanäle offensichtlich bei der Abwehr von P. contorta gegen die EU-Rasse von G. abietina wirksam. [source] COALESCENCE VERSUS COMPETITION: FIELD AND LABORATORY STUDIES OF INTRA- AND INTERSPECIFIC ENCOUNTERS AMONG COALESCING SEAWEEDSJOURNAL OF PHYCOLOGY, Issue 2000B. Santelices Classical ecological theory predicts that whenever growing individuals share a common and limiting resource, such as substratum in mid-intertidal and shallow subtidal habitats, preemptive competition will occur determining species abundance and distribution patterns. However, conspecificity of several ecologically dominant Rhodophyta may coalesce when grown in laboratory cultures. The extent at which intraspecific coalescence occurs in the field and whether the process may also happens during interspecific encounters remain to be determined. If intra- and interspecific coalescence effectively occurs, then coexistence through coalescence rises as an alternative to competition among red-algal dominated intertidal and shallow subtidal communities. Populations of Mazzaella laminarioides and Nothogenia fastigiata living in mid-intertidal, semi-exposed rocky habitats in Central Chile are being used to test the above ideas. Intra- and interspecific encounters occur in the field throughout the year. Coalescence does occur among conspecific partners but it has not been detected in interspecific encounters. Rather, a thick interface of compressed cells, necrotic tissues and cyanobacterial nodules is formed between the two contacting partners. In addition, observations of laboratory cultures indicate that spore germination, germling survival and differentiation of erect axes in bispecific cultures may be reduced when compared to single-species controls. Interspecific differences in growth and differentiation rates appear as the mechanisms explaining a lack of coalescence and negative effects during interspecific contacts. On the other hand, the existence of conspecific coalescence in the field suggests this process should be considered as a real alternative to intraspecific competition among coalescing Rhodophyta. [source] Successful topical hemotherapy with a new occlusive dressing for an intractable ulcer on the toeTHE JOURNAL OF DERMATOLOGY, Issue 4 2009Michiko IWAYAMA-HIBINO ABSTRACT Topical hemotherapy is a method of applying heparinized venous blood directly onto the surface of an ulcer, which is covered with an occlusive hydrocolloidal dressing. It is often effective on chronic ulcers with thick necrosis, because some proteinases and growth factors in plasma are probably involved in the digestion of necrotic tissues and the acceleration of granulation and epithelization. We treated a patient with an intractable ulcer on the toe caused by a peripheral circulatory disturbance due to her systemic sclerosis. As conventional topical hemotherapy cannot be applied to ulcers on the round tip of a toe, we made a device for occlusive dressing of topical hemotherapy which could successfully improve the previously refractory ulcer. [source] | ||||||||||||||||||||||||||||