North American Journal of Medicine and Science
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Renal Pseudotumor Due to Perirenal Fat Necrosis
Get PDFWe report the findings of an uncommon non-infectious cause of renal pseudotumor, perirenal fat necrosis, presenting as a native kidney mass in a renal transplant recipient. Resection was performed due to clinical suspicion for malignancy. To our knowledge this is the first report of a case of perirenal fat necrosis presenting in the transplant setting. This case emphasizes the need to continually expand our diagnostic considerations beyond epithelial and non-epithelial malignancies when confronted with native kidney masses in renal transplant recipients
A Mouse Model of Timothy Syndrome: a Complex Autistic Disorder Resulting from a Point Mutation in Cav1.2
Get PDFTimothy Syndrome (TS) arises from a point mutation in the human voltage-gated L-type Ca2+ channel (Cav1.2). TS is associated with cardiac arrhythmias and sudden cardiac death, as well as congenital heart disease, impaired cognitive function, and autism spectrum disorders. TS results from a de novo gain-of-function mutation which affects the voltage dependent component of Cav1.2 inactivation. We created a knock-in TS mouse. No homozygous TS mice survived, but heterozygous TS2-NEO mice (with the mutation and the neocassette in situ) had a normal outward appearance and survived to reproductive age. Previously, we have demonstrated that these mice exhibit the triad of Autistic traits. In this paper we document other aspects of these mice including Cav1.2 isoform expression levels, normal physical strength, brain anatomy and a marked propensity towards self-injurious scratching. Gross brain anatomy was not markedly different in TS2-NEO mice compared to control littermates, and no missing structures were noted. The lack of obvious changes in brain structure is consistent with theTS2-NEO mice may provide a significant tool in understanding the role of calcium channel inactivation in both cardiac function and brain development
Primary Mucinous Carcinoid of the Ovary Arising in a Mature Cystic Teratoma: A Case Report with Review of the Literature
Get PDFPrimary mucinous carcinoid of the ovary is an extremely rare neoplasm with less than thirty cases reported in the English literature. The clinical behavior and pathologic features have not been well characterized. Here we report a case of a 42-year-old female who underwent laparoscopic salpingo-oophorectomy for a left ovarian mass. The ovary was received for histopathologic evaluation in multiple pieces among which a 1.1 cm firm tan nodule was identified. Histologically, this nodule composed of small glandular structures scattered in pools of mucin adjacent to a mature cystic teratoma. The glands were lined by goblet and columnar cells and showed no appreciable atypia. Immunohistochemistry revealed intense, diffuse staining pattern of the mucinous tumor component for CK20, CDX-2 and villin and focal patchy positivity for CK7 and chromogranin. Metastatic tumors from the GI tract and Krukenberg tumors were considered in this patient’s differential diagnosis. She subsequently underwent a total abdominal hysterectomy with staging and appendectomy. However, no evidence of primary gastrointestinal malignancy or residual ovarian disease was found. The histologic and immunohistochemical characteristics of the tumor, its intimate association with a mature cystic teratoma and the absence of primary malignancy elsewhere are compatible with the diagnosis of a primary ovarian mucinous carcinoid tumor. This case is presented to raise the awareness of a rare tumor entity among the pathology and gynecologic communities.
Case Report: Pulmonary Benign Metastasizing Leiomyoma Appears 26 Years after Resection of Uterine Leiomyoma
Get PDFBenign metastasizing leiomyoma (BML) is a rare disease which usually presents as multiple pulmonary nodules several years (average 15 years) after the resection of uterine leiomyoma(s). Only about 100 cases of BML have been reported in English literature. Here we report an unusual case of BML identified 26 years after resection of uterine leiomyoma. The patient was a 44-year-old woman who was found to have an incidental lung nodule in the left lower lobe of lung during workup for a brain lesion that was biopsy-proven astrocytoma. A lung wedge resection was performed and a solid, well demarcated, 2.5 x 1.5 x 1.5 cm nodule was resected. The lesion was composed of bland appearing spindle cells without mitotic activity that were positive for smooth muscle actin, estrongen receptor and vimentin. CD117, S100, Synaptophysin, HMB-45, CD99, calretinin, pancytokeratin and CD10 were negative. MIB-1(Ki-67) staining showed very low proliferative index. In conclusion, the overall morphological and immunohistochemical features, and patient's remote history of primary uterine leiomyoma supported the diagnosis of pulmonary BML.
Pattern and Evolution of C4d Staining of Ischemic Myocardial Injury: Implications for the Interpretation of Post-Transplant Endomyocardial Biopsies
Get PDFC4d immunohistochemical staining is a marker of recent classical pathway complement activation that is useful for evaluation of antibody-mediated rejection in transplant biopsies. C4d also stains areas of myocyte necrosis. We describe the pattern and intensity of myocyte, interstitial, and microvascular staining at different stages of ischemic injury/infarction in the non- transplant setting. Thirty autopsies with ischemic injury were reviewed. Nine acute myocardial infarction, 3 contraction band necrosis, 9 subendocardial ischemic, and 9 chronic ischemic injury/scarring cases were stained with polyclonal antibody for C4d. Results: Acute myocardial infarction and subendocardial ischemic injury cases showed strong staining of necrotic myocytes; larger infarcts showed more intense peripheral versus central staining. Subendocardial ischemic injury was easier to quantify versus H&E staining. Necrosis with contraction bands was highlighted in individual myocytes. Two of 9 cases of chronic ischemic injury/scarring showed only rare positive cells. C4d was noted to highlight amyloid in 4 cases. Microvascular staining was noted in only 2 cases, was faint and not associated with injured areas. Autolysis had no effect on staining. C4d is a useful diagnostic tool to highlight necrotic myocytes, especially in the absence of large areas of obvious necrosis. It can be used to differentiate true from artifactual contraction band injury and can be used on autolyzed material. Microvascular staining is not seen around areas of infarction. This finding may help in the interpretation of perioperative ischemic injury versus humoral rejection in heart transplants, wherein microvascular staining in post-implantation biopsies should prompt additional clinical investigations to rule out humoral rejection
Primary Sclerosing Cholangitis: From Pathogenesis to Medical Management
Get PDFPrimary sclerosing cholangitis (PSC) is a cholestatic liver disease characterized by progressive inflammatory destruction of intrahepatic and extrahepatic bile ducts. It is strongly associated with inflammatory bowel disease, particularly ulcerative colitis. The pathogenesis of PSC remains unclear, however several hypotheses have been proposed that suggest roles for autoimmunity, genetic susceptibility, and the interaction between microorganisms and host immune response directed at the biliary system. A diagnosis of PSC is based on a constellation of clinical, biochemical, and typical cholangiographic features and usually without the need for liver histopathology. Complications of PSC include pruritus, portal hypertension, bone disease, end-stage liver disease, and cancers. Cholangiocarcinoma eventually develops in 8-15% of PSC patients. A variety of drugs have been evaluated as therapy for PSC, but no therapy has yet been proven to prolong survival or improve outcomes in PSC. Ursodeoxycholic acid (UDCA) has been intensively investigated to address its efficacy in PSC. A recent investigation noted that high-dose UDCA therapy in PSC did not confer benefit on combined clinical and survival endpoints. . Immunosuppressive agents are generally ineffective. Liver transplantation remains the only proven long-term treatment for advanced PSC, with approximately 20-25% risk of disease recurrence. Cancer surveillance, management of cirrhotic complications, and treatment of manifestations of cholestasis in those with PSC are clinically relevant. Further understanding of the pathogenesis of PSC is desperately required in order to effectively improve our current approaches to the management of this disease.
Speech and Language Impairments in Autism: Insights from Behavior and Neuroimaging
Get PDFA failure to develop language is one of the earliest signs of autism. The ability to identify the neural signature of this deficit in very young children has become increasingly important, given that the presence of speech before five years of age is the strongest predictor for better outcomes in autism. This review consolidates what is known about verbal and preverbal precursors of language development as a framework for examining behavioral and brain anomalies related to speech and language in autism spectrum disorders. Relating the disruptions in the speech network to the social deficits observed will provide promising targets for behavioral and pharmacological interventions in ASD
A Review of Angiomyolipoma and Its Morphological Variants
Get PDFAngiomyolipoma (AML) is defined as a benign clonal neoplasm composed of thick-walled blood vessels, smooth muscle cells and adipose tissue, belonging to the family of perivascular epithelioid cell tumors (PEComa). Morphologic variants of AML are composed of variable proportions of mature adipose tissue, thick-walled, poorly organized blood vessels, smooth muscle with or without feature of atypia and/or pleomorphism. Similar to all PEComas, AML demonstrates co-expression of melanocytic and smooth muscle markers, but negative for cytokeratin. This paper explores AML and its variants with the goal of distinguishing between these morphologic variants, and differentiating them from other renal malignancies
Regulatory T Cells and Cardiovascular Diseases
Get PDFRecent researches have substantiated the active participation of chronic low-grade inflammation in cardiovascular disease where immune responses contribute to disease initiation and progression. Regulatory T cells (Tregs) are a unique lineage of T cells and have been proved to play a key role in controlling both the innate and adaptive immune responses under physiological and pathological conditions. Through suppression of immune system activation, Tregs are involved in tolerance to self antigens, thus maintaining immune homeostasis. Existence and function of Tregs were a matter of considerable debate over the last few decades, but owing to innovative molecular categorization of this specialized subpopulation of T cells, they have now been established as fundamental elements in the vertebrate immune system. In view of the prospective therapeutic avenues that Tregs may offer, we hereby review the current knowledge on the role of Tregs immunity in cardiovascular disease
Macrophage Polarization and Inflammation at the Interface of Cardiovascular Disease and Metabolism
Get PDFClassically activated macrophages (M1) and alternatively activated macrophages (M2) are induced by Th1 and Th2 cytokines respectively. These macrophages are phenotypically and functionally different. Polarized macrophages are important players in inflammation because of the pro-inflammatory properties of M1 and the anti-inflammatory properties of M2. Under metabolic stress, interactions between polarized macrophages and adipocytes, hepatocytes, and skeletal myocytes mediate the inflammatory response that ultimately contributes to metabolic diseases. The crosstalk between polarized macrophages and endothelial cells, vascular smooth muscle cells, and possibly cardiomyocytes is important in the progression of cardiovascular diseases (CVDs). Moreover, inflammation and macrophage polarization present as critical links between metabolism and CVDs