Regenerative hyperplasia of follicular epithelium in chronic lymphocytic thyroiditis.

The thyroid gland is an endocrine organ composed of stable cells. It is well known that regenerative capacity of the thyroid tissue is minimal. Various degrees of morphologic alterations do occur in chronic lymphocytic thyroiditis (CLT), including Hashimoto's thyroiditis. Eighty-five CLT cases were analyzed for these morphologic alterations. Small, irregular, atrophic or hyperplastic thyroid follicles were seen adjacent to the lymphocytic infiltration. There was nuclear enlargement, loss of nuclear polarity in thyrocytes and intrafollicular thyrocyte proliferation in these follicles. We thought that the morphologic alterations in involved follicles could be due to regenerative hyperplasia with increased proliferative activity and basement membrane abnormalities. To examine this hypothesis we investigated Ki-67 and laminin immunoreactivity in the involved follicles adjacent to lymphocytic infiltration areas. The uninvolved follicles were used as controls. Immunopositivity of Ki-67 in involved follicles was significantly higher than that in uninvolved follicles (2.97% +/- 2.16 versus 0.83% +/- 1.63, P < 0.001). Laminin immunostaining indicated the destruction or irregular distribution of basement membrane in involved follicles. We conclude that the increased cell proliferation activity and basement membrane abnormalities in the follicles with morphologic changes adjacent to CLT occur in conjunction with regenerative hyperplasia.     

Role of Melatonin in Reducing Water Avoidance Stress-Induced Degeneration of the Liver

Melatonin, a pineal secretory product, is a potent scavenger of a variety of free radicals. We investigated the role of melatonin on water avoidance stress (WAS)–induced degenerations of the liver parenchyme. Wistar albino rats were exposed to acute WAS (aWAS group) or chronic WAS (cWAS group). Before exposing animals to acute (aWAS + mel group) or chronic WAS (cWAS + mel group), 10 mg/kg melatonin was injected i.p. The liver samples were investigated under light and transmission electron microscope. Malondialdehyde (MDA) and glutathione (GSH) levels were also determined. Prominent vascular congestion and dilated sinusoids, activated Kupffer cells with prominent morphology, dilated granular endoplasmic reticulum membranes, and focal picnotic nuclei were observed in the aWAS group; these morphological changes were severe in the cWAS group. MDA level was increased and GSH level was decreased significantly in the cWAS group. The morphology of liver parenchme in both the aWAS + mel and the cWAS + mel group showed that melatonin significantly reduced the degeneration in liver; besides, a significant decrease in MDA and an increase in GSH levels were observed in the cWAS + mel group. Based on the results, melatonin treatment significantly prevented WAS-induced morphological and biochemical changes in liver parenchyma.     

Early pulmonary involvement in Niemann-Pick type B disease: lung lavage is not useful

Niemann-Pick disease (NPD) is a rare, autosomal-recessively inherited lipid storage disease which is characterized by intracellular deposition of sphingomyelin in various body tissues. The disease is heterogeneous and classified into six groups. Pulmonary parenchymal involvement may be a feature of several subtypes of NPD, including type B. Progressive pulmonary involvement in NPD type B is a major cause of morbidity and mortality. It is usually diagnosed at older ages. Only a few cases with early pulmonary involvement have been reported. In this report, a patient with NPD type B, hospitalized with the diagnosis of pneumonia at age 3 months, is presented. Following treatment for pneumonia, she continued to have persistent respiratory symptoms and became oxygen-dependent. High-resolution computed tomography of the chest revealed diffuse interstitial changes. During follow-up, the patient developed hepatosplenomegaly. Lung, liver, and bone marrow biopsies showed characteristic findings for NPD. Biochemical studies also confirmed the diagnosis, and the sphingomyelinase enzyme level of the patient was low. Unilateral lung lavage was performed in order to decrease lipid storage as a treatment modality. However, there was no clinical or radiological improvement. The patient died at age 15 months due to progressive respiratory failure. Pulmonary involvement is a rare entity in early childhood in patients with NPD type B, but should be considered in the differential diagnosis of persistent interstitial lung disease. It may cause progressive respiratory failure, but the treatment options remain limited.     

Transoesophageal echocardiographic findings in patients with ischemic lacunar and nonlacunar stroke.

The aim of this study was to compare risk factors and concomitant potential cardioembolic sources detected by transthoracic (TTE) and transoesophageal echocardiography (TEE) in patients with lacunar and nonlacunar infarcts. Clinical data of 139 patients with a first episode of ischemic stroke who underwent both TTE and TEE were analysed. Patients were divided into two groups, lacunar (LACI=36), and nonlacunar infarcts (NLACI=103); then the latter group was divided into two subgroups, anterior (ACI=76) and posterior circulation infarct (POCI=27). Presence of hypertension and diabetes mellitus were not significantly different between LACI and NLACI groups. The rate of potential cardioembolic risk factors detected by echocardiography was similar in the NLACI groups. At least one potential cardiac source of embolism was identified in 44% (n=16) of LACI, 52.6% (n=40) of ACI and 55.5% (n=15) of POCI patients. Atrial fibrillation was significantly frequent in the ACI group. No significant differences were found between all groups regarding age, sex, hyperlipidemia, and smoking. Our findings demonstrate that hypertension and diabetes mellitus are equally important in the pathogenesis of both LACI and NLACI groups and there is a need for careful cardiac evaluation in cases even with lacunar infarct.     

Protective effect of melatonin on water avoidance stress induced degeneration of the bladder

PURPOSE: The role of melatonin on chronic water avoidance stress (WAS) induced degeneration of bladder epithelium (urothelium) was investigated. MATERIALS AND METHODS: Wistar albino rats were exposed to WAS for 2 hours daily for 5 days (WAS group). Before exposing them to WAS 10 mg/kg melatonin (WAS plus melatonin group) was injected intraperitoneally into the animals. Bladder samples were investigated with light and electron microscopy. Lipid peroxidation and glutathione levels were also measured in the bladder. RESULTS: In the WAS only group an increased number of mast cells in the mucosa, ulcerated areas, vacuole formation and dilated perinuclear cisternae, and dilatation in the intercellular spaces in the urothelium were observed. In the WAS plus melatonin group relatively normal urothelial topography, a decreased number of mast cells in the mucosa, some dilatation between intercellular areas, regular perinuclear cisternae and tight junctions were observed. Increased lipid peroxidation and decreased glutathione levels in WAS rats were reversed by melatonin. CONCLUSIONS: The results show that melatonin reverses WAS induced degenerative changes in the bladder.     

Osmotic pressure and vasculature of gingiva in periodontal disease: an experimental study in rats

Alterations in vascularisation, vasodilatation and tissue osmotic pressure (OP) are inevitable aspects of the inflammatory process that have an adverse effect on the fluid dynamics of the tissue involved. The aim of this study was to investigate tissue OP and its relationship with the vasculature in inflammed gingival tissues, in order to reveal the possible effects of vascular changes on OP in the fluid dynamics of periodontal soft tissues during periodontal disease. The parameters of fluid dynamics assessed in this study were OP, vascularisation and vasodilatation. Ligature-induced periodontitis was performed in 10 rats (test group), and gingival biopsies taken from the diseased teeth were utilised for the test procedures. These biopsies were compared with biopsies of the same teeth from 10 periodontally healthy rats (control group). OP was measured in mosmol/kg using a semi-micro digital osmometer. Vascularisation and vasodilatation were examined histopathologically; the number of vessels (VN) was quantified and the micrometric changes in vessel diameters (VD) were calculated as the alterations in the vasculature. OP, VN and VD were found to be higher in the test group (84.3+/-37.1 mosmol/kg, 13.2+/-3.2 and 19.5+/-1.3 microm, respectively) than the control group (11.6+/-3.8 mosmol/kg, 6.8+/-1.1 and 15.5+/-2.4 microm, respectively) (P<0.000). There was a strong, positive correlation between OP and VN (r=0.55, P<0.000) and a weak, negative correlation between OP and VD (r=0.1, P>0.05) in the test group. These results confirm that the OP of periodontal soft tissues does change during inflammatory conditions. The increase in OP during this process may be affected by increased vascularisation in the inflammed tissue.     

Effect of a controlled-release chlorhexidine chip on clinical and microbiological parameters and prostaglandin E2 levels in gingival crevicular fluid

BACKGROUND: The aim of the present study was to determine the effect of a chlorhexidine chip on crevicular prostaglandin E2 (PGE2) levels and on the clinical and microbiological parameters of periodontitis when used as adjunctive therapy to scaling and root planing (SRP) in patients with chronic periodontitis. METHODS: This randomized single-blind study was carried out in parallel design. The test group received SRP plus chlorhexidine chip, whereas the control group received SRP alone. Thirty-four subjects, aged 20 to 55 years, with chronic periodontitis were recruited. Clinical indices, microbiological samples, and gingival crevicular fluid (GCF) samples were evaluated at baseline and after 1, 3, and 6 months. Microbiological samples were evaluated under a light microscope. GCF PGE2 levels were determined using radioimmunoassay. RESULTS: Significant improvements could be found for all clinical variables in both groups over the study period. The mean changes in probing depth obtained by SRP plus chlorhexidine chip were greater than those obtained by the SRP alone group at 3 and 6 months. In the test group, there was also significant gain in clinical attachment level at 6 months. When data were combined from all groups, significant reductions in GCF PGE2 levels and number of microorganisms were noted at all time points. However, in the test group, reduction was greater at 6 months for crevicular PGE2 level and at 3 and 6 months for proportions of spirochetes. CONCLUSION: Based on the findings of this study, the chlorhexidine chip reduced GCF PGE2 levels and had positive effects on clinical parameters and subgingival flora when used as adjunctive therapy to SRP in patients with chronic periodontitis.