Histopathological findings and diagnosis of cutaneous leishmaniasis, confirmed by PCR, in an endemic region of Brazil.

INTRODUCTION: Diagnosis of cutaneous leishmaniasis (CL) is difficult, and the correct use of histopathological criteria can be useful in clinical practice. The present study evaluates the association between histopathological findings and the results of polymerase chain reaction (PCR) in clinically suspected cases of CL. METHODOLOGY: Skin samples were received in a laboratory from an endemic region of Brazil for over nine years. Associations were analyzed by means of the Chi square test with a 5% level of significance. RESULTS: Of the 222 examined samples, 190 (85.6%) tested positive by PCR. All 25 cases identified by microscopic examination also tested positive by PCR. Except for the more intense inflammatory infiltrate, all other evaluated histological variables (ulceration, epidermal hyperplasia, hyperkeratosis, presence of granuloma, neutrophils, histiocytes, lymphocytes, plasmocytes, and necrosis) were not significantly associated with PCR positivity. CONCLUSIONS: The intensity of the inflammatory infiltrate is a good indicator of the occurrence of CL. Histopathological aspects are useful to increase the predictive values of CL diagnoses, but PCR is still necessary to confirm or exclude the disease.

Ameliorative Potential of Bone Marrow-Derived Mesenchymal Stem Cells Versus Prednisolone in a Rat Model of Lung Fibrosis: A Histological, Immunohistochemical, and Biochemical Study.

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease of unknown origin with limited treatment options and poor prognosis. The encouraging findings from preclinical investigations utilizing mesenchymal stem cells (MSCs) indicated that they could serve as a promising therapeutic alternative for managing chronic lung conditions, such as IPF. The objective of this study was to compare the efficiency of bone marrow-derived MSCs (BM-MSCs) versus prednisolone, the standard anti-inflammatory medication, in rats with bleomycin (BLM)-induced lung fibrosis. Four groups were created: a control group, a BLM group, a prednisolone-treated group, and a BM-MSCs-treated group. To induce lung fibrosis, 5 mg/kg of BLM was administered intratracheally. BLM significantly increased serum levels of pro-inflammatory cytokines and oxidative stress markers. The disturbed lung structure was also revealed by light and transmission electron microscopic studies. Upregulation in the immune expression of alpha-smooth muscle actin, transforming growth factor beta-1, and Bax was demonstrated. Interestingly, all findings significantly regressed on treatment with prednisolone and BM-MSCs. However, treatment with BM-MSCs showed better results than with prednisolone. In conclusion, BM-MSCs could be a promising approach for managing lung fibrosis.

Sliding Window Optimal Transport for Open World Artifact Detection in Histopathology.

Histological images are frequently impaired by local artifacts from scanner malfunctions or iatrogenic processes - caused by preparation - impacting the performance of Deep Learning models. Models often struggle with the slightest out-of-distribution shifts, resulting in compromised performance. Detecting artifacts and failure modes of the models is crucial to ensure open-world applicability to whole slide images for tasks like segmentation or diagnosis. We introduce a novel technique for out-of-distribution detection within whole slide images, compatible with any segmentation or classification model. Our approach tiles multi-layer features into sliding window patches and leverages optimal transport to align them with recognized in-distribution samples. We average the optimal transport costs over tiles and layers to detect out-of-distribution samples. Notably, our method excels in identifying failure modes that would harm downstream performance, surpassing contemporary out-of-distribution detection techniques. We evaluate our method for both natural and synthetic artifacts, considering distribution shifts of various sizes and types. The results confirm that our technique outperforms alternative methods for artifact detection. We assess our method components and the ability to negate the impact of artifacts on the downstream tasks. Finally, we demonstrate that our method can mitigate the risk of performance drops in downstream tasks, enhancing reliability by up to 77%. In testing 7 annotated whole slide images with natural artifacts, our method boosted the Dice score by 68%, highlighting its real open-world utility.

Characterization of Crude and Processed Pulp Cell Walls of Three Selected Mamey Accessions (Mammea americana L.).

Mamey (Mammea americana L.) is a tropical fleshy fruit native from the West Indies and northern South America. It is very appreciated for its flavor and color but has been little described. The present study investigates the composition and histochemistry of the pulp cell walls of three mamey accessions readily available in Martinique. The impact of pulp processing into puree on cell wall composition is evaluated. The histology and rheology of mamey puree are assessed considering these characterizations. Mamey pulp cell wall composition is dominated by highly methyl-esterified pectins (DM: 66.2-76.7%) of high molecular weight, and show few hemicelluloses, mainly xyloglucans. Processing reduced methyl-esterified uronic acid contents and gave purees with significantly different viscosities. Mamey puree was composed of polydisperse particles (20-2343 µm), which size distributions were different depending on the accession: Ti Jacques was dominated by smaller particles (50% had approximated diameters lower than 160 µm), Sonson's by larger particles (50% had approximated diameters higher than 900 µm), and Galion's had an intermediate profile. This new knowledge on mamey pulp is valuable for future works on mamey processing into new food products, even more so for those including cell wall polysaccharide-degrading enzymes.

Lectins As Effective Tools in the Study of the Biliary Network and the Parenchymal Architecture of the Zebrafish (Danio rerio) Liver.

Lectins are carbohydrate-binding proteins with specific affinity to glycoconjugates expressed in various tissues. Lectins are of substantial utility as research, histochemical, and diagnostic tools in mammalian systems. Reactivity of 12 commonly used plant-based lectins was studied in zebrafish liver. Four lectins, tomato lectin (TL), wheat germ agglutinin, concanavalin A, and Jacalin showed strong reactivity to hepatic parenchymal structures. Importantly, TL reacted to glycoconjugates within segments of the larval and adult intrahepatic biliary network, from canaliculi to bile ducts. We provide evidence that lectins can serve as important histochemical tools to investigate the structural and functional characteristics of the zebrafish liver.

A rare case report of liver masses caused by Actinomyces species.

Actinomycosis is a rare infection caused by Actinomyces spp. Of all actinomycosis infections, only 5% of Hepatic Actinomycosis (HA) infection has been reported. This disease is often misdiagnosed as a malignancy. This case report presents a 45-year-old woman with diabetes, initially suspected of intrahepatic cholangiocarcinoma, but after careful tissue staining, we found the results supported HA infection.

First confirmed case of equine pythiosis in Northern Veracruz, Mexico.

A clinical case of an adult horse with invasive, ulcerative, proliferative, pyogranulomatous disease of the skin (tumor) in the shoulder region is presented. The mass had a granulomatous and crater-shaped appearance, with serosanguinous discharge and the presence of fistulas with caseous material. The tumor was removed by surgery and sent to the laboratory for diagnosis. Histopathology was performed using Grocott-Gomori methenamine silver stain. The presence of necrotic material, fibrosis, infiltrated cells, and brown-colored hyphae, characteristic of members of the genus Pythium, were observed. To identify the infecting species, conventional PCRs for the amplification of the ITS-1 was carried out. Histopathological and PCR tests confirmed infection by a Pythium insidiosum strain closely associated with previous records from the US and Central America. Our report represents the first molecularly confirmed case of equine pythiosis in Mexico.

A Comprehensive Study of Meningioma Biomineralization: Morphological, Crystallographic, and Immunohistochemical Aspects.

Biomineralization of brain tissues occurs both in normal and pathological conditions. Dura mater biomineralization is widespread and occurs in 1-72% of cases, depending on the patient's age and research method. The amount of biomineral deposits under the conditions of tumor growth in the meninges only increases, reaching 100% in the case of psammomatous meningiomas. Since calcifications are often found in the meninges, the problem of differential diagnosis with calcified meningiomas arises. A total of 30 samples of meningiomas with signs of biomineralization-dense structure, characteristic crunch, psammoma bodies (group I) and 30 samples of meningiomas without any signs of biomineralization were examined as controls (group II). To detect pathological biomineralization, the meningioma tissue was studied using the methods of macroscopic description, histology, histochemistry, and immunohistochemistry, scanning electron microscopy with microanalysis, and transmission electron microscopy. A significantly higher level of caspase3 and features of the expression of osteoblastic markers (a lower level of OPG expression and a higher level of the presence of RANKL in group I, the absence of fluctuations in the expression of SPARC) may indicate a dystrophic type of development of biomineral deposits in meningiomas.

Adult extrarenal teratoid Wilms' tumor: A case report and review of literature.

ABSTRACT: A 19-year-old woman presented with painless lower abdominal discomfort and a cystic-solid mass measuring 15.9 cm on the right ovary. She subsequently underwent laparoscopic right ovarian cystectomy. Microscopic examination of the mass showed the typical morphological features of Wilms' tumor and the predominance of teratoid elements constituting more than 50% of the tumor. To date, few cases of extrarenal teratoid Wilms' tumor (TWTs) in adults have been reported in the literature. The case presented in the present is the third reported case of adult extrarenal TWT occurring in ovary.

Poorly differentiated biphasic synovial sarcoma of the vulva, displaying SS18::SSX1 fusion and weak to absent (mosaic) INI1/SMARCB1 immunostaining: A rare case with literature review.

ABSTRACT: Synovial sarcoma (SS) is rarely documented in the female genital tract, especially confirmed by molecular testing for SYT::SSX translocation and TLE1 immunostaining. A 62-year-old lady presented with a progressively increasing lump and pain over her right groin, for 6-month duration. Radiologically, a well-defined, solid-cystic mass was seen involving the right labia with necrotic areas, sparing the underlying muscles and the overlying skin. She underwent a biopsy followed by a surgical excision. Histopathologic examination revealed a spindle cell sarcoma, including tumor cells exhibiting a prominent hemangiopericytomatous pattern. There were focal areas of epithelial differentiation (pseudoglandular) along with areas of round cell morphology and increased mitoses (poor differentiation) in the resected specimen. Immunohistochemically, the tumor cells were diffusely positive for TLE1, patchily positive for pan keratin (AE1/AE3) and EMA, the latter more in the areas of epithelial differentiation, while negative for CD34, SMA, desmin, S100P, and SOX10. INI1/SMARCB1 showed a characteristic weak to absent (mosaic) staining pattern. Furthermore, the tumor displayed SS18::SSX 1 fusion by RT-PCR. This constitutes one of the few reported cases of vulvar SS, confirmed by molecular testing and the first documented vulvar SS showing a mosaic pattern of INI1/SMARCB1 immunostaining. A review of the literature and diagnostic implications are presented herewith.

Primary extranodal NK/T cell lymphoma of stomach: A case report and review of literature.

ABSTRACT: Extranodal Natural killer/T (NK/T) cell lymphoma nasal type is an aggressive non-Hodgkin lymphoma and has a constant association with Epstein-Barr virus (EBV) infection. Approximately more than 75% cases are located in upper aero-digestive tract, of which stomach is a very rare site. Very few cases of gastric extranodal NK/T cell lymphoma have been reported in the literature. A 22-year-old male patient presented with complaints of abdominal pain and hematemesis. Endoscopy showed a large ulcer in the stomach. Partial gastrectomy done and histopathology showed transmural infiltration by intermediate size atypical lymphoid cells which are immunopositive for CD3, CD56, TIA, EBV-encoded RNA (EBER) and negative for CD4, CD8, CD20. A diagnosis of extranodal NK/T cell lymphoma nasal type was made.

Extranodal nasal-type NK/T-cell lymphoma with CD20 positive: A case report and review of literature.

ABSTRACT: Extranodal nasal-type natural killer (NK)/T-cell lymphoma is a type of non-Hodgkin lymphoma. Neoplastic lymphocytes are positive for CD4, CD56, and CD20, a specific B-cell marker. CD20 positive NK/T-cell lymphoma is rare, with only nine reported cases. This paper reports a case of nasal-type NK/T-cell lymphoma with CD20 positivity in a 47-year-old woman. The patient presented with bilateral nasal congestion and bloody nasal cavity secretions for 2 months. Computed tomography revealed thickening of the nasal mucosa and posterior wall of the nasopharyngeal crest, and the left and right cervical lymph nodes were enlarged. On histopathology, the lesion was composed of medium-sized atypical lymphoid cells and vascular infringement. Immunohistochemical staining showed that the tumor cells were positive for CD20, CD3, CD56, and Epstein-Barr virus (EBV)-encoded RNA in situ hybridization. The patient was treated with radiotherapy for 2 months and is currently well.

Exsanguinated to death by a perforated duodenal ulcer: Masquerader apprehended on autopsy.

ABSTRACT: Gastroduodenal perforation commonly due to spontaneous perforation of a pre-existing peptic ulcer is a surgical emergency. On laparotomy, approximately 60%-70% perforations are duodenal and 15%-20% gastric. The most prevalent etiology are Helicobacter pylori infection in 65%-70% and non-steroidal anti-inflammatory drugs (NSAIDS) abuse in 30%-50% cases depending on the prevalence of H. pylori infection. We report here the autopsy findings in a 29-year-old male who collapsed suddenly in the emergency room of our hospital after a bout of massive hematemesis.