Histopathological changes in the perivisceral fat body of Rhinocricus padbergi (Diplopoda, Spirobolida) triggered by biosolids

Human activities generate a great amount of sewage daily, which is dumped into the sewer system. After sewage-treatment processes, sewage sludge is generated. Such byproduct can be treated by different methods; the result of treatment is a stabilized compost of reduced pathogenicity that has a similar inorganic chemical composition to the raw sewage sludge. After such pretreatment, sewage sludge is called a biosolids, and it can be used in agriculture. In this contest, the present study evaluated the effects of a sample of biosolids on the perivisceral fat body of a diplopod. These invertebrates are soil organisms that play an important role in the dynamics of terrestrial ecosystems, and as a consequence, they are in contact with xenobiotics present in this environmental compartment. Special emphasis is given on the interpretation of the effects of complex mixtures in target organs of diplopods. A semiquantitative analysis for the evaluation of histopathological changes in the perivisceral fat body was proposed. The sample-induced histopathological and ultrastructural changes in individuals exposed to it, and the severity of the effects was positively related to the exposure time, resulting in the deaths of exposed individuals after 90 days. Thus, the results indicate the need for caution in the use of biosolids as well as the need for improving waste management techniques, so they will produce environmentally innocuous final products.

Histopathological and cytological analysis of transmissible venereal tumor in dogs after two treatment protocols

The transmissible venereal tumor (TVT) is a contagious neoplasm of round cells that frequently affect dogs. The treatment consists of chemotherapy being more effective the vincristine alone, however the resistance emergence to this agent due multidrug resistance of the P-glycoprotein (P-gp), a transporter protein encoded by the MDR1 gene, has been taking the association with other drugs. Recent studies demonstrated the antitumoral effect of the avermectins when associated to the vincristine in the treatment of some neoplasms. Therefore, the objective of the present study was to compare the effectiveness of standard treatment of TVT with vincristine only as compared to combined treatment with vincristine and ivermectin, evaluated through number of applications of the two protocols, histopathological and cytological analysis from 50 dogs diagnosed with TVT during the period of 2007 to 2010. The combined protocol significant reduces the number of applications and cytological and histopathological findings collaborate with the hypothesis that the combination of vincristine and ivermectin promotes faster healing than the use of vincristine alone. Combination treatment with vincristine and ivermectin could be in the future an excellent therapeutic alternative for the treatment of TVT for probably reducing the resistance to vincristine, simultaneously reducing the cost of TVT treatment and a faster recovery of the dog.

Necklace fibers as histopathological marker in a patient with severe form of X-linked myotubular myopathy

X-linked myotubular myopathy due to mutations in the MTM1 gene is classically characterized by a severe neonatal phenotype and a typical muscle biopsy presenting globular and centrally located nuclei in muscle myofibers. Recently, four patients with mild late-onset form have been described, a male with a hemizygous mutation and three females with heterozygous mutations in the MTM1 gene. The muscle biopsies were performed at 13-35 years of age and a new histological marker, the necklace fibers, was described. Here, we report two siblings with the pathogenic c.664 C > T mutation in the MTM1 gene, presenting a severe muscle weakness and respiratory impairment requiring ventilatory support since the first months of life until death, at the age of 36 months and 5 months. In the older brother the muscle biopsy, performed at the age of 30 months, showed almost 100% of necklace fibers, which were not present in the younger one submitted to muscle biopsy at 5 months of age. Our findings confirm the necklace fibers can be a histopathological finding of MTM1 myopathies, even in the severe neonatal form, and suggest that the necklace fibers appear or increase in number over time. (C) 2012 Elsevier B.V. All rights reserved.

Phoneutria nigriventer spider toxin Tx2-6 causes priapism and death: A histopathological investigation in mice

Phoneutria nigriventer spider bite causes priapism, an effect attributed to the peptide toxins Tx2-5 and Tx2-6 and involving nitric oxide. Tx2-6 (MW = 5287) is known to delay the inactivation of Sodium channels in the same fashion as many other venom toxins. In the present study we evaluated the i.p. dose that induces priapism and the other symptoms in mice. Animals killed by the toxin or crude venom (0.85 mg/kg) were autopsied and a pathological study of brain, lung, kidney, liver and heart was undertaken using standard techniques. The same protocol was employed with animals injected with crude venom. Results showed that priapism is the first sign of intoxication, followed by piloerection, abundant salivation and tremors. An i.p. injection of about 0.3 mu g/kg induced only priapism with minimal side-effects. The most remarkable histological finding was a general vascular congestion in all organs studied. Penis showed no necrosis or damage. Lungs showed vascular congestion and alveolar hemorrhage. Heart showed also sub-endothelial hemorrhage. Brain showed only a mild edema and vascular congestion. Results obtained with crude venom closely resemble those of purified toxin. We conclude that Tx2-6 have profound effects on the vascular bed especially in lungs and heart, which may be the cause of death. Interestingly brain tissue was less affected and the observed edema may be attributed to respiratory impairment. To the best of our knowledge this is the first histopathological investigation on this toxin and venom suggesting a possible cause of death. (C) 2012 Elsevier Ltd. All rights reserved.

Clinical, histopathological and immunohistochemical assessment of human skin field cancerization before and after photodynamic therapy

Background The field cancerization concept in photodamaged patients suggests that the entire sun-exposed surface of the skin has an increased risk for the development of (pre)-malignant lesions, mainly epithelial tumours. Topical photodynamic therapy (PDT) is a noninvasive therapeutic method for multiple actinic keratosis (AK) with excellent outcome. Objectives To evaluate the clinical, histological and immunohistochemical changes in human skin with field cancerization after multiple sessions of PDT with methyl-aminolaevulinate (MAL). Methods Twenty-six patients with photodamaged skin and multiple AK on the face received three consecutive sessions of MAL-PDT with red light (37 J cm(-2)), 1 month apart. Biopsies before and 3 months after the last treatment session were taken from normal-appearing skin on the field-cancerized area. Immunohistochemical stainings were performed for TP-53, procollagen-I, metalloproteinase-1 (MMP-1) and tenascin-C (Tn-C). Results All 26 patients completed the study. The global score for photodamage improved considerably in all patients (P < 0.001). The AK clearance rate was 89.5% at the end of the study. Two treatment sessions were as effective as three MAL-PDT sessions. A significant decrease in atypia grade and extent of keratinocyte atypia was observed histologically (P < 0.001). Also, a significant increase in collagen deposition (P = 0.001) and improvement of solar elastosis (P = 0.002) were noticed after PDT. However, immunohistochemistry showed only a trend for decreased TP-53 expression (not significant), increased procollagen-I and MMP-1 expressions (not significant) and an increased expression of Tn-C (P = 0.024). Conclusions Clinical and histological improvement in field cancerization after multiple sessions of MAL-PDT is proven. The decrease in severity and extent of keratinocyte atypia associated with a decreased expression of TP-53 suggest a reduced carcinogenic potential of the sun-damaged area. The significant increase of new collagen deposition and the reduction of solar elastosis explain the clinical improvement of photodamaged skin.

Upregulation of soluble and membrane-bound human leukocyte antigen G expression is primarily observed in the milder histopathological stages of chronic hepatitis C virus infection

Chronic hepatitis C virus (HCV) infection is a worldwide health problem that may evolve to cirrhosis and hepatocellular carcinoma. Incompletely understood immune system mechanisms have been associated with impaired viral clearance. The nonclassical class I human leukocyte antigen G (HLA-G) molecule may downregulate immune system cell functions exhibiting well-recognized tolerogenic properties. HCV genotype was analyzed in chronic HCV-infected patients. Because HLA-G expression may be induced by certain viruses, we evaluated the presence of HLA-G in the liver microenvironment obtained from 89 biopsies of patients harboring chronic HCV infection and stratified according to clinical and histopathological features. Overall, data indicated that HCV genotype 1 was predominant, especially subgenotype 1a, with a prevalence of 87%. HLA-G expression was observed in 45(51%) liver specimens, and it was more frequent in milder stages of chronic hepatitis (67.4%) than in moderate (27.8%; p = 0.009) and severe (36.0%; p = 0.021) stages of the disease. Altogether, these results suggest that the expression of HLA-G in the context of HCV is a complex process modulated by many factors, which may contribute to an immunologic environment favoring viral persistence. However, because the milder forms predominantly expressed HLA-G, a protective role of this molecule may not be excluded. (C) 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Histopathological evaluation and risk factors related to the development of pouchitis in patients with ileal pouches for ulcerative colitis

OBJECTIVE: Many changes in mucosal morphology are observed following ileal pouch construction, including colonic metaplasia and dysplasia. Additionally, one rare but potential complication is the development of adenocarcinoma of the reservoir. The aim of this study was to evaluate the most frequently observed histopathological changes in ileal pouches and to correlate these changes with potential risk factors for complications. METHODS: A total of 41 patients were enrolled in the study and divided into the following three groups: a non-pouchitis group (group 1) (n = 20; 8 males; mean age: 47.5 years) demonstrating optimal outcome; a pouchitis without antibiotics group (group 2) (n = 14; 4 males; mean age: 47 years), containing individuals with pouchitis who did not receive treatment with antibiotics; and a pouchitis plus antibiotics group (group 3) (n = 7; 3 males; mean age: 41 years), containing those patients with pouchitis who were administered antibiotics. Ileal pouch endoscopy was performed, and tissue biopsy samples were collected for histopathological analysis. RESULTS: Colonic metaplasia was found in 15 (36.6%) of the 41 patients evaluated; of these, five (25%) were from group 1, eight (57.1%) were from group 2, and two (28.6%) were from group 3. However, no correlation was established between the presence of metaplasia and pouchitis (p = 0.17). and no differences in mucosal atrophy or the degree of chronic or acute inflammation were observed between groups 1, 2, and 3 (p > 0.45). Moreover, no dysplasia or neoplastic changes were detected. However, the degree of mucosal atrophy correlated well with the time of postoperative follow-up (p = 0.05). CONCLUSIONS: The degree of mucosal atrophy, the presence of colonic metaplasia, and the degree of acute or chronic inflammation do not appear to constitute risk factors for the development of pouchitis. Moreover, we observed that longer postoperative follow-up times were associated with greater degrees of mucosal atrophy.

Antimicrobial Photodynamic Therapy for the Treatment of Teeth with Apical Periodontitis: A Histopathological Evaluation

Introduction: This study evaluated the in vivo response of apical and periapical tissues of dogs' teeth with apical periodontitis after one-session endodontic treatment with and without antimicrobial photodynamic therapy (aPDT). Methods: Sixty root canals with experimentally induced apical periodontitis were instrumented and assigned to 4 groups receiving aPDT and root canal filling (RCF) or not: group aPDT+/RCF- (n = 20): aPDT (photosensitizer phenothiazine chloride at 10 mg/mL for 3 minutes and diode laser [2 = 660 nm, 60 mW/cm(2)] for 1 minute) and RCF in the same session; group aPDT+/RCF (n = 10); group aPDT /RCF+ (n = 20), and group aPDT /RCF (n = 10). Teeth were restored, and the animals were killed after 90 days. Sections from the maxillas and mandibles were stained with hematoxylin-eosin and Mallory trichrome and examined under light microscopy. Descriptive (ie, newly formed apical mineralized tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, and mineralized tissue resorption) and quantitative (ie, periapical lesion size and number of inflammatory cells) microscopic analysis was performed. Quantitative data were analyzed by the Kruskal-Wallis and Dunn tests (alpha =.05). Results: In the aPDT-treated groups, the periapical region was moderately/severely enlarged with no inflammatory cells, moderate neoangiogenesis and fibrogenesis, and the smallest periapical lesions. Conclusions: Although apical closure by mineralized tissue deposition was not achieved, the absence of inflammatory cells, moderate neoangiogenesis, and fibrogenesis in the periapical region in the groups treated with aPDT indicate that this can be a promising adjunct therapy to cleaning and shaping procedures in teeth with apical periodontitis undergoing one-session endodontic treatment. (J Endod 2012;38:360-366)

Eruption sequestrum - case report and histopathological findings

Eruption sequestrum is an uncommon disturbance in eruption and consists of small fragments of calcified tissue overlying the crowns of erupting permanent molar teeth, especially at the time of eruption of the mandibular first molars. This paper reports a case of unilateral eruption sequestrum in a 7-year-old Brazilian boy and describes its histopathological findings. A white small fragment, 0.5 cm in diameter, with hard consistency, irregular shape and located on the occlusal surface of the erupting mandibular left first molar was excised. Microscopic examination revealed large trabeculae with empty lacunae and a minimal amount of existing spongy bone consisting of acute inflammatory cells (neutrophils). Signs of necrosis were found on the periphery. The histological analysis was consistent with non-vital bone and the diagnosis of eruption sequestrum was established. Clinical and radiographic follow-up visits scheduled at short intervals and then every 6 months revealed normal postoperative conditions.

CO2 and diode laser for excisional biopsies of oral mucosal lesions. A pilot study evaluating clinical and histopathological parameters

PURPOSE: The present pilot study evaluates the histopathological characteristics and suitability of CO2 and diode lasers for performing excisional biopsies in the buccal mucosa with special emphasis on the extent of the thermal damage zone created. PATIENTS AND METHODS: 15 patients agreed to undergo surgical removal of their fibrous hyperplasias with a laser. These patients were randomly assigned to one diode or two CO2 laser groups. The CO2 laser was used in a continuous wave mode (cw) with a power of 5 W (Watts), and in a pulsed char-free mode (cf). Power settings for the diode laser were 5.12 W in a pulsed mode. The thermal damage zone of the three lasers and intraoperative and postoperative complications were assessed and compared. RESULTS: The collateral thermal damage zone on the borders of the excisional biopsies was significantly smaller with the CO, laser for both settings tested compared to the diode laser regarding values in pm or histopathological index scores. The only intraoperative complication encountered was bleeding, which had to be controlled with electrocauterization. No postoperative complications occurred in any of the three groups. CONCLUSIONS: The CO2 laser seems to be appropriate for excisional biopsies of benign oral mucosal lesions. The CO2 laser offers clear advantages in terms of smaller thermal damage zones over the diode laser. More study participants are needed to demonstrate potential differences between the two different CO2 laser settings tested.

Extraintestinal Crohn's disease mimicking autoimmune inner ear disease: a histopathological approach

Patients with autoimmune inner ear disease develop rapidly progressive sensorineural hearing loss over a period of several weeks or months, often accompanied by vestibular loss. This disease can occur as a distinct clinical entity or in association with an underlying autoimmune disorder. Treatment comprises immunosuppression by corticosteroids, cytostatic drugs or tumor necrosis factor- antagonists. We report histopathological and immunohistochemical findings of the inner ear of a patient with a granulomatous inner ear disease suffering from Crohn's disease that was nonresponsive to treatment and who underwent surgery for bilateral cochlear implants.

Dental erosion--an overview with emphasis on chemical and histopathological aspects

The quality of dental care and modern achievements in dental science depend strongly on understanding the properties of teeth and the basic principles and mechanisms involved in their interaction with surrounding media. Erosion is a disorder to which such properties as structural features of tooth, physiological properties of saliva, and extrinsic and intrinsic acidic sources and habits contribute, and all must be carefully considered. The degree of saturation in the surrounding solution, which is determined by pH and calcium and phosphate concentrations, is the driving force for dissolution of dental hard tissue. In relation to caries, with the calcium and phosphate concentrations in plaque fluid, the 'critical pH' below which enamel dissolves is about 5.5. For erosion, the critical pH is lower in products (e.g. yoghurt) containing more calcium and phosphate than plaque fluid and higher when the concentrations are lower. Dental erosion starts by initial softening of the enamel surface followed by loss of volume with a softened layer persisting at the surface of the remaining tissue. Dentine erosion is not clearly understood, so further in vivo studies, including histopathological aspects, are needed. Clinical reports show that exposure to acids combined with an insufficient salivary flow rate results in enhanced dissolution. The effects of these and other interactions result in a permanent ion/substance exchange and reorganisation within the tooth material or at its interface, thus altering its strength and structure. The rate and severity of erosion are determined by the susceptibility of the dental tissues towards dissolution. Because enamel contains less soluble mineral than dentine, it tends to erode more slowly. The chemical mechanisms of erosion are also summarised in this review. Special attention is given to the microscopic and macroscopic histopathology of erosion.

Factors predicting prognosis and recurrence in patients with esophago-gastric adenocarcinoma and histopathological response with less than 10 % residual tumor

PURPOSE: Neoadjuvant treatment is an accepted standard approach for treating locally advanced esophago-gastric adenocarcinomas. Despite a response of the primary tumor, a significant percentage dies from tumor recurrence. The aim of this retrospective exploratory study from two academic centers was to identify predictors of survival and recurrence in histopathologically responding patients. METHODS: Two hundred thirty one patients with adenocarcinomas (esophagus: n = 185, stomach: n = 46, cT3/4, cN0/+, cM0) treated with preoperative chemotherapy (n = 212) or chemoradiotherapy (n = 19) followed by resection achieved a histopathological response (regression 1a: no residual tumor (n = 58), and regression 1b < 10 % residual tumor (n = 173)). RESULTS: The estimated median overall survival was 92.4 months (5-year survival, 56.6 %) for all patients. For patients with regression 1a, median survival is not reached (5-year survival, 71.6 %) compared to patients with regression 1b with 75.3 months median (5-year survival, 52.2 %) (p = 0.031). Patients with a regression 1a had lymph node metastases in 19.0 versus 33.7 % in regression 1b. The ypT-category (p < 0.001), the M-category (p = 0.005), and the type of treatment (p = 0.04) were found to be independent prognostic factors in R0-resected patients. The recurrence rate was 31.7 % (n = 66) (local, 39.4 %; peritoneal carcinomatosis, 25.7 %; distant metastases, 50 %). Recurrence was predicted by female gender (p = 0.013), ypT-category (p = 0.007), and M-category (p = 0.003) in multivariate analysis. CONCLUSION: Response of the primary tumor does not guarantee recurrence-free long-term survival, but histopathological complete responders have better prognosis compared to partial responders. Established prognostic factors strongly influence the outcome, which could, in the future, be used for stratification of adjuvant treatment approaches. Increasing the rate of histopathological complete responders is a valid endpoint for future clinical trials investigating new drugs.

Liver fat quantification by dual-echo MR imaging outperforms traditional histopathological analysis

The aim of this study was to evaluate the accuracy of dual-echo (DE) magnetic resonance imaging (MRI) with and without fat and water separation for the quantification of liver fat content (LFC) in vitro and in patients undergoing liver surgery, with comparison to histopathologic analysis.

Viral load, organ distribution, histopathological lesions, and cytokine mRNA expression in goats infected with a molecular clone of the caprine arthritis encephalitis virus

Caprine arthritis encephalitis virus (CAEV) is a lentivirus of goats that causes persistent infection characterized by the appearance of inflammatory lesions in various organs. To define the sites of persistence, 5 goats were infected with a molecular clone of CAEV, and the viral load was monitored by real-time-PCR and RT-PCR in different sites 8 years after infection. The lymph nodes proved to be an important virus reservoir, with moderate virus replication relative to what is reported for lentiviruses of primates. Mammary gland and milk cells were preferred sites of viral replication. The viral load varied significantly between animals, which points to an important role of the genetic background. We found a clear association between occurrence of histopathological lesions and viral load in specific sites. The mRNA expression analysis of several cytokines did not reveal differences between animals that could explain the considerable individual variations in viral load observed.