Immunocytochemical detection of effects of TRH and T4 on prolactin- and TSH-producing cells in the pituitary gland of Rana ridibunda

Effects of synthetic thyrotropin-releasing hormone (TRH) and various doses of thyroxin (T4) on prolactin (PRL)-producing cells and thyrotropic cells in the pituitary were investigated in adult male and female Rana ridibunda frogs. Animals were given 200 microg TRH once a week for 4 weeks and 0.2-0.5 mg T4 during 3 days per week for a period of 2 weeks by injections in the groin. PRL-producing cells and thyrotropic cells were identified with light microscopical and electron microscopical immunocytochemical methods, using rabbit anti-PRL and rabbit anti-thyroid stimulating hormone (TSH) as primary antibodies. TRH caused cytological changes in both cell types, which were consistent with increased synthesis and release of both PRL and TSH. Treatment with 0.5 mg T4 activated both cell types less than TRH treatment did, whereas 0.2 and 0.4 mg T4 caused inactivation of both cell types. In conclusion, mammalian TRH is effective on both types of frog pituitary cells. Our study suggests that T4 has a positive rather than a negative effect when concentrations above a certain threshold are given.     

The diagnostic value of magnetic resonance imaging in subacromial impingement syndrome

The aim of this study was to assess the diagnostic ability of magnetic resonance imaging (MRI) in subacromial impingement syndrome (SIS), using a physiological standard of reference. MRI of the rotator cuff (RC) and subacromial injection test (SIT), a reference standard for SIS diagnosis, were performed in 125 painful shoulders. MRI diagnostic accuracies were determined using a 2 x 2 table and the percentage values of SIS diagnosis in patients with the three Zlatkin MRI stages were determined. Shoulder function was evaluated using the Constant Scale, and results were compared for stages. The sensitivity, specificity, accuracy, positive and negative predictive values of MRI for SIS diagnosis were 98.85%, 36.84%, 80%, 78.18% and 93.33% respectively. Of the 32 patients with Zlatkin stage 1 changes in MRI, 20 (62%) had SIT approved SIS diagnosis, while 47 (79%) of the 59 patients with Zlatkin 2 and all of the 19 (100%) patients with Zlatkin 3 changes were diagnosed with SIS by SIT. Mean Constant scores were 78.04 +/- 18.3, 65.0 +/- 19.9 and 54.52 +/- 20.7 in patients with Zlatkin stages 1, 2 and 3, respectively (p < 0.05). The MRI of RC did not prove to be an excellent tool for SIT based SIS diagnosis, with its low specificity. However, the technique can give important clues, as its sensitivity and negative predictive values are high.     

Comparison of the effects of acarbose and metformin use on ovulation rates in clomiphene citrate-resistant polycystic ovary syndrome

BACKGROUND: The aim of this study was to evaluate the effects of metformin and acarbose on insulin resistance, hormone profiles and ovulation rates in patients with clomiphene citrate-resistant polycystic ovary syndrome (PCOS). METHODS: Thirty clomiphene citrate-resistant patients were selected randomly and divided into two groups. Group I was treated with 100 mg/day clomiphene citrate and 300 mg/day acarbose 100 mg/day orally, for 3 months. Group II was treated with clomiphene citrate 100 mg/day and metformin 1700 mg/day orally, for 3 months. Serum fasting insulin and glucose, FSH, LH, estradiol, progesterone, prolactin and total testosterone levels plus body mass index (BMI) were measured before and after treatment. Follicle growth was followed by transvaginal ultrasonography. RESULTS: LH:FSH ratio and total testosterone concentrations decreased (P<0.05) and ovulation rates increased in both groups. Reduction in weight and BMI was only significant in the acarbose group. CONCLUSIONS: Both treatment modalities were effective in the treatment of insulin resistance and improving ovulation rates. Increase in the number of eumenorrhoeic and normoinsulinaemic cases and decrease in the number of insulin-resistant cases were significant in both groups (P<0.05). Ovulation rate was greater in the metformin group in the second month of therapy (P<0.05). Acarbose was found to be a safe and effective agent that could be used in cases with clomiphene-resistant PCOS.     

Mutagenic potentials of dental cements as detected by the Salmonella/microsome test

The potential mutagenicity of a zinc phosphate (Poscal), a polycarboxylate (Aqualox) and glass ionomer cements with (Argion) and without (Meron) silver reinforcement were characterized by employing the Ames Salmonella/microsome test. The materials were eluted in dimethyl sulphoxide or physiologic saline and the aliquots were used either immediately or after an incubation period of 24h at 37 degrees C. Mutagenic effects of the materials were tested on Salmonella typhimurium strains TA 98, TA 100, TA 102 and TA 1535 using the standard plate incorporation assay, and in the presence or absence of S9 fraction from rat liver. Poscal and Aqualox elicited mutagenic effects on S. typhimurium TA 98 and TA 1535, whereas Meron exhibited mutagenic effects on S. typhimurium TA 98. No mutagenic effects were detected for Argion. The type of solvent, dose of the material and incubation as well as the interactions between these factors exhibited varying degrees of influences on the mutagenic activities of the cements (P<0.05 and P<0.1). We conclude that zinc phosphate, polycarboxylate, and glass ionomer cements may have possible mutagenic activities.     

Changes in cyclic nucleotides during the calcium paradox in the isolated rat heart

Reperfusion of hearts with a Ca²⁺-containing medium after a perfusion period in Ca²⁺-free medium results in irreversible cell damage (calcium paradox). In this investigation we have studied coronary flow and cyclic AMP and cyclic GMP levels after several periods of Ca²⁺-free perfusion in isolated rat hearts. We also investigated the effects of papaverine (Pap), noradrenaline (NA), acetylcholine (ACh) and absence of inorganic phosphate during Ca²⁺-free perfusion on coronary flow (CF) and cyclic nucleotide levels. Inability of the heart to recover contractile activity with development of contracture during the reperfusion period was accepted as indicative of the calcium paradox. Ca²⁺-free perfusion alone and NA and absence of inorganic phosphate during the Ca²⁺-free perfusion period increased CF, whereas Pap and ACh decreased it. However, only Ca²⁺-free perfusion and NA elevated cyclic AMP. On the other hand, Pap and ACh increased cyclic GMP (with a transient rise of cyclic AMP in Pap infusion), and absence of inorganic phosphate decreased both cyclic AMP and cyclic GMP. Pap, ACh and absence of phosphate prevented the calcium paradox. Our study suggests that increased cyclic AMP during the Ca²⁺-free perfusion may contribute, with the other factors, to the occurrence of the calcium paradox.     

Ruptur der Pectoralis-major-Sehne und anderer extraartikulärer Sehnen an der Schulter

Die Unfallchirurgie - Rupturen der M.-pectoralis-major(PM)-Sehne sind seltene Verletzungen, jedoch hat ihre Zahl v.?a. bei der Ausübung von Kraftsport in den letzten Jahren zugenommen....     

Biliary–enteric fistulas: report of five cases and review of the literature

Internal biliary fistulas (IBF) are seen rarely. Because the symptoms and signs of IBF are not specific and the diagnosis is not suspected, these patients are commonly investigated with plain abdominal films (PAF), ultrasonography (US), upper gastrointestinal series (UGIS), barium enema (BE), and computed tomography (CT), but not always with endoscopic retrograde cholangiopancreatography (ERCP). The purposes of this article are (a) to attract attention of radiologists to presumptive findings of IBF, so as not to misdiagnose this unsuspected and rare disease, and (b) review of the literature while presenting radiologic features of our cases. Five cases of IBFs in which extrahepatic biliary tree communicating with duodenum (four cases) and colon (one case) are reported. Diagnostic work-up of cases were done by PAF, US, UGIS, BE, and CT. Aerobilia, which cannot be explained using other means, ectopic gallstone and small bowel dilatation, nonvisualization of the gallbladder despite no history of cholecystectomy, and thick-walled shrunken gallbladder adherent to neighboring organs were suggestive findings of IBF in our study. Knowledge of imaging findings suggestive of IBF and a high index of suspicion increase the diagnostic rate of IBFs. Received: 4 June 1998; Revision received: 28 July 1998; Accepted: 14 October 1998     

Effects of dextran and pentoxifylline on hemorrhagic shock-induced P-selectin expression

BACKGROUND: Dextran and pentoxifylline have been shown to prevent leukocyte-endothelium adherence encountered after hemorrhagic shock. P-Selectin is the first endothelial cell adhesion molecule to be upregulated after an ischemic insult. We investigated the effects of resuscitation with dextran 70 and administration of pentoxifylline during resuscitation on hemorrhagic shock-induced P-selectin expression. MATERIAL AND METHODS: Hemorrhagic shock was induced in C57BL/6 mice by withdrawing blood to reduce mean arterial blood pressure to 30 mm Hg for 45 min. Animals were resuscitated by infusing one of the following solutions (each n:5): (1) Ringer's lactate, (2) 6% dextran 70, (3) Ringer's lactate plus 50 mg/kg pentoxifylline, (4) 5% human albumin. Afterward shed blood was infused. In vivo P-selectin expression was determined using dual-radiolabeled monoclonal antibody technique in lung, heart, liver, kidney, mesentery, stomach, small bowel, and colon 5 h after resuscitation. RESULTS: P-Selectin was significantly upregulated in all of the organs studied in the Ringer's lactate resuscitation group (P < 0.001). Resuscitation with dextran 70 and administration of pentoxifylline during resuscitation prevented P-selectin upregulation. Resuscitation with human albumin caused significant attenuation but could not prevent P-selectin upregulation (p < 0.01). CONCLUSION: Our study implies that the prevention of hemorrhagic shock-induced leukocyte-endothelium adherence by dextran 70 and pentoxifylline observed in other studies may be mediated by prevention of P-selectin expression by these agents.