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81.
We report a rare case of extragonadal germ cell tumour in a 55-year-old man. He presented with a painless mass in right inguinal region, a few days after hernioplasty for right direct inguinal hernia, which caused diagnostic difficulties and treatment problems.  相似文献   
82.
Monoamines are implicated in the modulation of adult hippocampal neurogenesis in depression models and following chronic antidepressant treatment. Given the key role of Sonic hedgehog (Shh) in adult neurogenesis, we examined whether monoaminergic perturbations regulate the expression of Shh or its co-receptors Smoothened (Smo) and Patched (Ptc). Combined depletion of both serotonin and norepinephrine with para-chlorophenylalanine (PCPA) resulted in a significant decrease in Smo and Ptc mRNA within the dentate gyrus subfield of the hippocampus. However, selective depletion of serotonin, using the serotonergic neurotoxin 5,7-dihyrdroxytryptamine (5,7-DHT), or norepinephrine, using the noradrenergic neurotoxin DSP-4, did not alter expression of Shh and its co-receptors, Smo and Ptc. Acute treatment with the monoamine releasing agent, para-chloroamphetamine (PCA) significantly upregulated Smo mRNA within the dentate gyrus. However, acute or chronic treatment with pharmacological antidepressants that modulate monoaminergic neurotransmission did not regulate Shh cascade expression. These results indicate that robust changes in monoamine levels can regulate the expression of the Shh signaling cascade in the adult rodent brain.  相似文献   
83.
Risk stratification, based on the Gleason score (GS) of a prostate biopsy, is an important decision‐making tool in prostate cancer management. As low‐grade disease may not need active intervention, the ability to identify aggressive cancers on imaging could limit the need for prostate biopsies. We assessed the ability of multiparametric MRI (mpMRI) in pre‐biopsy risk stratification of men with prostate cancer. One hundred and twenty men suspected to have prostate cancer underwent mpMRI (diffusion MRI and MR spectroscopic imaging) prior to biopsy. Twenty‐six had cancer and were stratified into three groups based on GS: low grade (GS ≤ 6), intermediate grade (GS = 7) and high grade (GS ≥ 8). A total of 910 regions of interest (ROIs) from the peripheral zone (PZ, range 25–45) were analyzed from these 26 patients. The metabolite ratio [citrate/(choline + creatine)] and apparent diffusion coefficient (ADC) of voxels were calculated for the PZ regions corresponding to the biopsy cores and compared with histology. The median metabolite ratios for low‐grade, intermediate‐grade and high‐grade cancer were 0.29 (range: 0.16, 0.61), 0.17 (range: 0.13, 0.32) and 0.13 (range: 0.05, 0.23), respectively (p = 0.004). The corresponding mean ADCs (×10–3 mm2/s) for low‐grade, intermediate‐grade and high‐grade cancer were 0.99 ± 0.08, 0.86 ± 0.11 and 0.69 ± 0.12, respectively (p < 0.0001). The combined ADC and metabolite ratio model showed strong discriminatory ability to differentiate subjects with GS ≤ 6 from subjects with GS ≥ 7 with an area under the curve of 94%. These data indicate that pre‐biopsy mpMRI may stratify PCa aggressiveness noninvasively. As the recent literature data suggest that men with GS ≤ 6 cancer may not need radical therapy, our data may help limit the need for biopsy and allow informed decision making for clinical intervention. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
84.
In the course of Chronic myeloid leukemia (CML), appearance of increased number of blasts may herald evolution of accelerated phase as well as onset of marrow fibrosis (MF) thereby necessitating the need to perform trephine biopsy for correct diagnosis and appropriate treatment. In the existing grading systems of MF, a comprehensive view has not been taken of the variability of density and area occupied by reticulin and collagen fibres. To overcome this shortcoming, we quantitated the reticulin and collagen content of marrow, its pattern of distribution and percentage area occupied by each type of fibres in every individual case. We performed 50 bone marrow (BM) trephine biopsies in patients of CML in order to assess the incidence and degree of MF. Various grades of MF were correlated with peripheral smear including blast count, bone marrow aspirate and LAP score of the case. A positive correlation was found between increasing grades of MF and number of megakaryocytes in the BM.  相似文献   
85.
The coronavirus disease 2019 (COVID-19) pandemic continues to be a global problem with over 438 million cases reported so far. Although it mostly affects the respiratory system, the involvement of extrapulmonary organs, including the liver, is not uncommon. Since the beginning of the pandemic, metabolic com-orbidities, such as obesity, diabetes, hypertension, and dyslipidemia, have been identified as poor prognostic indicators. Subsequent metabolic and lipidomic studies have identified several metabolic dysfunctions in patients with COVID-19. The metabolic alterations appear to be linked to the course of the disease and inflammatory reaction in the body. The liver is an important organ with high metabolic activity, and a significant proportion of COVID-19 patients have metabolic comorbidities; thus, this factor could play a key role in orchestrating systemic metabolic changes during infection. Evidence suggests that metabolic dysregulation in COVID-19 has both short- and long-term metabolic implications. Furthermore, COVID-19 has adverse associations with metabolic-associated fatty liver disease. Due to the ensuing effects on the renin-angiotensin-aldosterone system and ammonia metabolism, COVID-19 can have significant implications in patients with advanced chronic liver disease. A thorough understanding of COVID-19-associated metabolic dysfunction could lead to the identification of important plasma biomarkers and novel treatment targets. In this review, we discuss the current understanding of metabolic dysfunction in COVID-19, focusing on the liver and exploring the underlying mechanistic pathogenesis and clinical implications.  相似文献   
86.
Adamantinoma-like Ewing sarcoma (ALES) is a histological subtype of Ewing sarcoma that demonstrates the morphological and immunohistochemical features of the latter, harbors the EWSR1::FLI1 gene fusion, and additionally demonstrates complex epithelial differentiation on morphology and immunohistochemistry. Accurate preoperative diagnosis has potential to inform management and improve patient outcome. Cytomorphology of ALES is not well documented, with available reports showing a spectrum of features. An aspirate from a 30-year-old male with a swelling in right parotid region, interpreted elsewhere as acinic cell carcinoma (ACC), was submitted to us for review. Smears showed dispersed cells and loosely cohesive clusters with scant cytoplasm and large nuclei with focal nuclear molding, prompting a diagnosis of malignant neoplasm, possibly neuroendocrine carcinoma. Cytoplasmic vacuoles and tigroid background were present focally, the former of which had possibly led to interpretation as ACC. No material was available for ancillary tests. Parotidectomy revealed features of ALES. The cytological features of ALES in the parotid overlap with several basaloid and round blue cell neoplasms that are more common at this site. ALES should be considered in all salivary gland aspirates with isomorphic small round or basaloid cells, with or without the presence of squamous differentiation. Rosettes, cytoplasmic vacuoles, and a tigroid background are subtle morphological clues to the diagnosis, which if suspected on cytomorphology, can be confirmed using ancillary techniques.  相似文献   
87.
Mumps is an acute infectious disease caused by mumps virus, a member of the family Paramyxoviridae. With the implementation of vaccination programs, mumps infection is under control. However, due to resurgence of mumps epidemics, there is a renewed interest in understanding the antigenic diversity of mumps virus. Hemagglutinin-neuraminidase (HN) is the major surface antigen and is known to elicit neutralizing antibodies. Mutational analysis of HN of wild-type and vaccine strains revealed that the hypervariable positions are distributed over the entire length with no detectable pattern. In the absence of experimentally derived 3D structure data, the structure of HN protein of mumps virus was predicted using homology modeling. Mutations mapped on the predicted structures were found to cluster on one of the surfaces. A predicted conformational epitope encompasses experimentally characterized epitopes suggesting that it is a major site for neutralization. These analyses provide rationale for strain specificity, antigenic diversity and varying efficacy of mumps vaccines.  相似文献   
88.

Background:

Anastomotic leak is a serious complication after major gastrointestinal surgery and majority of deaths occur due to septic shock. Therefore, the early identification of risk factors of septic shock may help reduce the adverse outcomes.

Objective:

The aim of this audit was to determine the predictors of septic shock in patients with anastomotic leak after major gastrointestinal surgery.

Design:

Retrospective, audit.

Materials and Methods:

The patients admitted in the gastrosurgical intensive care unit ICU) of our institute between September 2009 and April 2012 with anastomotic leakage after surgery were identified. The ICU charts were retrieved from the database to identify the patients progressing to septic shock. A comparison of risk factors was made between the patients who developed septic shock (septic shock group) against the patients who did not (non-septic shock group).

Results:

The study sample comprised of 103 patients with anastomotic leak, of which 72 patients developed septic shock. The septic shock group had a higher APACHE II score, lower MAP, and higher HR at the time of ICU admission. They received greater transfusion of packed red blood cells during their ICU stay. Septic shock was more common after pancreaticojejunostomy and hepaticojejunostomy leaks.

Conclusion:

Presence of malignancy, chronic obstructive pulmonary disease (COPD), packed red blood cell transfusion, bacteremia, and hepaticojejunostomy or pancreaticojejunostomy leaks were independent predictors of mortality and length of ICU stay. To the best of our knowledge there are no available studies in the literature on the predictors of risk factors of septic shock in patients with anastomotic leakage.  相似文献   
89.
Intrapancreatic and intraabdominal accessory spleens (IPIASs) are rarely encountered in endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) biopsies. However, as incidentally discovered IPIAS can mimic a benign or malignant pancreatic neoplasm on imaging studies, a definitive diagnosis made by EUS‐FNA can avert an unnecessary surgical intervention or additional radiologic follow‐up. We report five cases of intrapancreatic splenules and one case of accessory spleen (AS) in which a definitive diagnosis was made on EUS‐FNA. Previously recognized FNA cytomorphologic features of splenic tissue, including ASs and splenosis, are endothelial cells and polymorphous lymphocytes admixed with neutrophils, eosinophils, plasma cells, histiocytes, and lymphoglandular bodies. We describe the additional finding of abundant large platelet aggregates as another distinguishing feature of splenic tissue on FNA. In all six cases, large platelet aggregates were identified along with polymorphous lymphoid cells, lymphoglandular bodies, loose aggregates of endothelial cells and scattered or aggregated bland spindle cells. A review of 10 consecutive cases of EUS‐FNA‐sampled benign intraabdominal lymph nodes showed that the presence of large platelet aggregates, three‐dimensional aggregates of lymphoid cells and of bland slender spindle cells and the absence of follicular germinal cell components (tingible body macrophages and lymphohistiocytic aggregates) are useful in differentiating IPIASs from reactive lymph nodes. Immunoperoxidase stains were useful to confirm a suspected IPIASs by showing CD31‐positive acellular flocculent material, consistent with large platelet aggregates and a rich CD8‐positive endothelial cell network between CD45‐positive lymphoid cells and CD68‐positive histiocytes in all six cases. Diagn. Cytopathol. 2013;41:661–672. © 2013 Wiley Periodicals, Inc.  相似文献   
90.
Endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) allows a reliable and accurate diagnosis of neoplasms of the gallbladder and bile ducts. We report the cytopathologic findings of a case of large cell neuroendocrine carcinoma (LCNEC) of the gallbladder and extrahepatic bile ducts in a 67‐year‐old woman who presented with progressive abdominal pain and jaundice. EUS‐FNA of the mass involving the common bile duct and of a porta hepatis lymph node showed abundant cellularity with tumor cells arranged singly and occasionally in tight and loose clusters and rosette‐like structures in a background showing extensive necrotic debris. The tumor cells were predominantly plasmacytoid, showed a moderate amount of focally vacuolated cytoplasm and large round to oval hyperchromatic nuclei with prominent nucleoli, numerous mitoses, and apoptotic bodies. The differential diagnosis included poorly differentiated adenocarcinoma, lymphoma, melanoma, and poorly differentiated neuroendocrine carcinoma (NEC), large cell type. The tumor cells were strongly and diffusely positive for cytokeratin AE1/AE3, CD56, synaptophysin, and chromogranin and showed a very high proliferative fraction on Ki67 staining, supporting the diagnosis of a high‐grade NEC. Due to the large size of the neoplastic cells, moderate amounts of cytoplasm and prominent nucleoli, a diagnosis of LCNEC was made on the EUS‐FNA sample. Despite the prompt institution of chemotherapy, the patient died shortly thereafter and the diagnosis was confirmed at autopsy. This is to our knowledge the first case of LCNEC of the gallbladder and bile ducts diagnosed by EUS‐FNA. Diagn. Cytopathol. 2013;41:1091–1095. © 2012 Wiley Periodicals, Inc.  相似文献   
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