Minimization of the Risk of Diabetic Microangiopathy in Rats by Nigella sativa.

BACKGROUND: Microangiopathy is a chronic diabetic complication resulting from metabolic derangements, oxidative stress, and increased pro-inflammatory cytokine production. Nigella sativa Linn. is used as an herbal medicine that exerts hypoglycemic, antilipidemic, anti-inflammatory, and antioxidant effects. OBJECTIVE: To examine the effects of N. sativa extract on cutaneous microvascular changes in diabetic rats. MATERIALS AND METHODS: Sprague-Dawley rats were randomly assigned into the following four groups: Untreated and N. sativa-treated normal controls and untreated and N. sativa-treated rats with streptozotocin-induced diabetes. A cold-pressed N. sativa extract was then orally administered (1000 mg/kg/day). After 8 weeks of treatment, the glucose, glycosylated hemoglobin (HbA1c), tumor necrosis factor-alpha (TNF-α), insulin levels, and lipid profile were determined in cardiac blood. Dermal capillary wall thickness was measured in tail skin sections stained with periodic acid-Schiff. Endothelial apoptosis was morphologically evaluated by hematoxylin and eosin staining. RESULTS: Diabetes significantly reduced the circulating insulin and low-density lipoprotein levels and caused elevations in the glucose, HbA1c, and triglyceride levels, accompanied by a slight increase in total cholesterol levels and no change in the high-density lipoprotein and TNF-α levels. Capillary basement membrane thickening and a decreased capillary luminal diameter despite no evidence of endothelial cell apoptosis were also observed. N. sativa treatment of diabetic rats reduced the mean HbA1c concentration by 1.4%, enlarged the capillary lumens, and tended to attenuate dermal capillary basement membrane thickening without affecting the lipid profile or TNF-α level. CONCLUSION: Our results indicate that N. sativa may be used to minimize the risk of diabetic microangiopathy, potentially due in part to its glycemic control activity. SUMMARY: Diabetes causes dermal capillary basement membrane thickening and a decreased capillary luminal diameterNigella sativa treatment of diabetic rats enlarged the capillary lumens and tended to attenuate dermal capillary basement membrane thickeningN. sativa treatment of diabetic rats reduced the mean glycosylated hemoglobin concentration by 1.4%, which exceeds the necessary reduction previously described to decrease the risk of diabetic microangiopathy, without affecting the lipid profile or tumor necrosis factor-alpha levelN. sativa improves rat diabetic microangiopathy, potentially due in part to its glycemic control activity. Abbreviations used: H and E: Hematoxylin and eosin, HbA1c: Glycosylated hemoglobin, HDL-C: High-density lipoprotein cholesterol, LDL-C: Low-density lipoprotein cholesterol, PAS: Periodic acid-Schiff, STZ: Streptozotocin.

Invasive fungal disease in university hospital: a PCR-based study of autopsy cases.

Invasive fungal disease (IFD) has high mortality rate, especially in the growing population of immunocompromised patients. In spite of introduction of novel diagnostic approaches, the intravital recognition of IFD is challenging. Autopsy studies remain a key tool for assessment of epidemiology of visceral mycoses. We aimed to determine species distribution and trends of IFD over the last 10 years in unselected autopsy series from a large university hospital. Forty-five cases of visceral mycoses, confirmed by histopathology and panfungal PCR, were found in 587 consecutive autopsies. Major underlying diseases were diabetes mellitus (20%), hematologic malignancies (15.6%) and systemic lupus erythematosus (15.6%). There was a high risk for disseminated IFD in immunocompromised patients stayed in the hospital over 1 month with a fever longer than 3 weeks. The most common fungi were Aspergillus spp. (58%), Candida spp. (16%), Mucorales (14%) and Fusarium spp. (10%). We found significant increase in Aspergillus flavus (P = 0.04) and Mucorales (P < 0.01) infections over the last 5 years. Concordance rate between histopathology and panfungal PCR was 89.5% to the genus level. All 6 cases of fusariomycosis were misinterpreted as aspergillosis by histology alone. The precise species identification, necessary for targeted antifungal treatment, was rendered only by the molecular technique. Panfungal PCR showed high performance on formalin-fixed paraffin-embedded specimens, providing important epidemiological data in retrospective autopsy series. Rapid detection of fungi by panfungal PCR assay has high potential for intravital diagnostics of IFD in surgical and biopsy specimens.

High mast cell density associated with granulomatous formation in tuberculous lymphadenitis.

Mast cells are one of the main inflammatory cells involved in the pathogenesis of tuberculosis. Previous reports revealed that mast cells participated in both acute and chronic states of infection with Mycobacterium tuberculosis through direct contact or indirect enhancement by releasing mediators. The authors evaluated mast cell density on tissue sections of tuberculous lymphadenitis stained with 0.1% toluidine blue from 45 cases, all of which were retrieved from the surgical pathology files of King Chulalongkorn Memorial Hospital from 1999 to 2006. A number of mast cells were correlated semiquantitatively with granulomas which were formed by aggregation of epithelioid histiocytes, multinucleated giant cells, and caseous necrosis. We found that mast cell density was significantly increased in lymph nodes with greater granuloma involvement (p = 0.030) and multinucleated giant cell formation (p = 0.010). These findings indicate a significant correlation between mast cell density and the granulomatous formation responsible for M. tuberculosis.

Association between different variants of papillary thyroid carcinoma and risk-group according to AMES (age, metastasis, extent and size) classification system.

OBJECTIVE: To study the association between cell variants of papillary carcinoma and AMES (Age, Metastasis, Extent and Size) risk classification. MATERIAL AND METHOD: One hundred and twenty-one cases of papillary thyroid carcinomas were subclassified for cell type and risk-groups according to AMES classification system. Correlations between both variables are evaluated RESULTS: Among different cell variants of papillary carcinoma, solid cell pattern has the highest proportion of high-risk tumor classified by the AMES criteria, comprising 75% followed by tall cell subtype with 33.3% of high risk patients. Conventional papillary carcinoma has only 8.3% of high-risk group. Follicular and encapsulated variants as well as microcarcinoma (< 1 cm) are all categorized as low-risk neoplasms. CONCLUSION: The present study indicates that there is association between cell variants and AMES prognostic index. The authors, therefore, emphasize the importance of cell variants in predicting the prognosis of papillary carcinoma.

RET proto-oncogene expression of papillary thyroid carcinomas in Thai patients.

BACKGROUND: Ret proto-oncogene activation has been found in papillary thyroid carcinoma with different frequencies according to geographic location. The rate of expression ranges from 0-100 percent in the literature. This gene expression has also been studied in many Asian countries but it has never been studied in Thailand. OBJECTIVE: To study the frequency of the RET expression and their roles in predicting prognosis of papillary thyroid carcinoma among Thai patients treated at King Chulalongkorn Memorial Hospital, Bangkok, Thailand. MATERIAL AND METHOD: One hundred and one cases of papillary carcinomas were studied with immunohistochemistry for RET antibodies. All slides with routine staining were reviewed to classify cell variants and record other prognostic parameters such as size, multicentricity, extrathyroid invasion. The clinical data such as age and sex were also included for analyses. RESULTS: Forty-seven of the total 101 cases (46.5%) showed positive RET protein staining. The mean age among patients with RET negative neoplasms was 43.9 years compared with 39.8 years in RET positive group (p = 0.16). The average size of the tumors without RET expression was 2.5 cm, slightly larger than the RET positive tumors (2.1 cm)(p = 0.26). Extrathyroid invasion of the RET-positive tumors was found to be 33.2 percent while the RET negative neoplasms had 38.8 percent of this feature (p = 1). According to AMES score, the RET positive cases had only 11 percent of high-risk tumors, whereas the RET negative group comprised 23.1 percent of high-risk malignancies (p = 0.20). There was no significant difference in RET expression among cell variants (p = 1). CONCLUSION: The study of 101 papillary thyroid carcinomas at the King Chulalongkorn Memorial Hospital disclosed high frequency of RET expression (46.5%) and this is the only data among Thai patients that has ever been documented in the literature. Although, the gene expression in the tumor tends to be associated with good prognostic features but it was not distinct enough to be statistically significant.