Sentinel node biopsy in early breast cancer in Taiwan

The purpose of this study is to report the results of sentinel node (SN) biopsy for assessment of early breast cancer in Taiwan and to compare our results with those in other Asian countries and worldwide. We used methylene blue dye to identify SN in patients with clinically non-palpable breast mass and palpable breast mass smaller than 3 cm. We also explored the role of imprint cytology and immunochemical studies to identify metastatic cancer cells in the lymph nodes. A total of 221 procedures on 218 patients were performed by a single surgeon. The SN was identified in 85.5% of the cases. The overall accuracy of identifying tumors in SN was 97.4%, with a sensitivity of 90.9%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 96.4%. The use of immunochemical techniques helped to identify micrometastasis in SN or non-SN. Our results on SN biopsy with the dye method were similar to those reported from Japan and elsewhere. We concluded that sentinel node biopsy, together with the use of immunochemical techniques to identify micrometastatic foci, has allowed surgeons to decide at the time of surgery whether to perform axillary node dissection.     

Brain lipid peroxidation and changes of trace metals in rats following chronic manganese chloride exposure

The aim of this study was to investigate the effects of chronic, daily, 30-d administration of manganese chloride (MnCl2) to male Sprague-Dawley rats on lipid peroxidation and changes of trace elements (manganese, iron, copper, zinc) in various brain regions. Rats were intraperitoneally injected with MnCl2 (20 mg/kg) once daily for 30 consecutive days. The Mn accumulated in frontal cortex, corpus callosum, hippocampus, striatum, hypothalamus, medulla, cerebellum, and spinal cord. Malondialdehyde, an end product of lipid peroxidation, was markedly decreased in frontal cortex and cerebellum. An increased level of Cu was observed in frontal cortex, medulla, and a cerebellum. A decreased Fe level was found only in cerebellum, and a decreased Zn level was observed in hippocampus and striatum. In a second group of animals, Mn (20 mg/kg/d) and glutathione (GSH, 15 mg/kg/d) were administered ip for 30 d. In CSH-Mn-treated rats, compared to Mn-treated rats, MDA concentrations were significantly reduced in frontal cortex, medulla and cerebellum. The changes of trace elements in rat brain were similar to the Mn-treated group. We suggest that Mn is an atypical antioxidant, as well as not involved in oxidative damage in rat brain. Fe and Cu may play roles in the protective effect of Mn against lipid peroxidation in rat brain.     

Modulation of L-type Ca(2+) channels by distinct domains within SNAP-25

Cognate soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins are now known to associate the secretory vesicle with both the target plasma membrane and Ca(2+) channels in order to mediate the sequence of events leading to exocytosis in neurons and neuroendocrine cells. Neuroendocrine cells, particularly insulin-secreting islet beta-cells, t-SNARE proteins, 25-kDa synaptosomal-associated protein (SNAP-25), and syntaxin 1A, independently inhibit the L-type Ca(2+) channel (L(Ca)). However, when both are present, they actually exhibit stimulatory actions on the L(Ca). This suggests that the positive regulation of the L(Ca) is conferred by a multi-SNARE protein complex. We hypothesized an alternate explanation, which is that each of these SNARE proteins possess distinct inhibitory and stimulatory domains that act on the L(Ca). These SNARE proteins were recently shown to bind the Lc(753-893) domain corresponding to the II and III intracellular loop of the alpha1C subunit of the L(Ca). In this study, using patch-clamp methods on primary pancreatic beta-cells and insulinoma HIT-T15 cells, we examined the functional interactions of the botulinum neurotoxin A (BoNT/A) cleavage products of SNAP-25, including NH(2)-terminal (1-197 amino acids) and COOH-terminal (amino acid 198-206) domains, on the L(Ca), particularly at the Lc(753-893) domain. Intracellular application of SNAP-25(1-206) in primary beta-cells decreased L(Ca) currents by approximately 15%. The reduction in L(Ca) currents was counteracted by coapplication of Lc(753-893). Overexpression or injection of wild-type SNAP-25 in HIT cells reduced L(Ca) currents by approximately 30%, and this inhibition was also blocked by the recombinant Lc(753-893) peptide. Expression of BoNT/A surprisingly caused an even greater reduction of L(Ca) currents (by 41%), suggesting that the BoNT/A cleavage products of SNAP-25 might possess distinct inhibitory and positive regulatory domains. Indeed, expression of SNAP-25(1-197) increased L(Ca) currents (by 19% at 10 mV), and these effects were blocked by the Lc(753-893) peptide. In contrast, injection of SNAP-25(198-206) peptide into untransfected cells inhibited L(Ca) currents (by 47%), and more remarkably, these inhibitory effects dominated over the stimulatory effects of SNAP-25(1-197) overexpression (by 34%). Therefore, the SNARE protein SNAP-25 possesses distinct inhibitory and stimulatory domains that act on the L(Ca). The COOH-terminal 197-206 domain of SNAP-25, whose inhibitory actions dominate over the opposing stimulatory NH(2)-terminal domain, likely confers the inhibitory actions of SNAP-25 on the L(Ca). We postulate that the eventual accelerated proteolysis of SNAP-25 brought about by BoNT/A cleavage allows the relatively intact NH(2)-terminal SNAP-25 domain to assert its stimulatory action on the L(Ca) to increase Ca(2+) influx, and this could in part explain the observed weak or inconsistent inhibitory effects of BoNT/A on insulin secretion. The present study suggests that distinct domains within SNAP-25 modulate L(C) subtype Ca(2+) channel activity in both primary beta-cells and insulinoma HIT-T15 cells.     

Choroidal osteoma masquerading as central serous chorioretinopathy

We report a rare case of choroidal osteoma masquerading as central serous chorioretinopathy. A 39-year-old man complained of intermittent episodes of blurred vision in the left eye for 2 months. Fundus examination of the left eye showed a dome-shaped elevation at the macular center. Fluorescein angiography showed a patch of pinpoint leakage resulting in a well-defined pool of dye at the macular center. Initial diagnosis was recurrent central serous chorioretinopathy with sequelae in the left eye. Five months later, serous detachment recurred. Computerized tomography and ultrasonography showed a bony plaque at the choroid level, and choroidal osteoma was diagnosed.     

Serial body composition by bioimpedance analysis in a diabetic subject with rapid insulin-induced weight gain--a case report

Insulin treatment is well known to induce progressive body weight gain. However, rapid weight increase due to transient fluid accumulation is rare. Bioelectrical impedance analysis (BIA) is a convenient method for determining body composition and water content. We report an 18-year-old diabetic female with rapid insulin-induced weight gain due to excessive body water retention, found by serial BIA measurement. The patient was admitted to our hospital due to uncontrolled diabetes. She had an initial body weight of 55 kg and height of 165 cm. However, a weight gain of 6.5 kg was noted one week after starting insulin injections and further increased to 8 kg after the second week. Finally a net weight increase of 4 kg from fat and lean mass was attained after two months. The weekly BIA data showed that most of the initial weight gain came from water retention, peaking on day 14 and recovering afterwards. Rapid weight gain shortly after insulin therapy may be due to excessive but reversible water retention, detected by repeated BIA measurements.     

Nasal teeth: report of three cases

The ectopic eruption of the teeth into the nasal cavity is a rare phenomenon. We report cases: two involving the nasal cavity and one involving the hard palate and complicated by Aspergillus rhinitis. We describe the clinical and radiologic presentation of these cases and discuss their etiology, complications, diagnosis, and treatment.