Anterior mediastinal mass with hyperthyroidism; report of a case

The patient was a 27-year-old man who had been diagnosed as having hyperthyroidism and with an anterior mediastinal mass which was reduced in size after anti-thyroid therapy. This mass was thought to be thymic hyperplasia associated with hyperthyroidism. An anterior mediastinal mass accompanying hyperthyroidism should be surgically treated when it dose not regress after an appropriate antithyroid therapy or there is a clinical suspicion of malignancy.     

Pulsed holmium:yttrium-aluminum-garnet laser-induced liquid jet as a novel dissection device in neuroendoscopic surgery

OBJECT: A pressure-driven continuous jet of water has been reported to be a feasible tool for neuroendoscopic dissection owing to its superiority at selective tissue dissection in the absence of thermal effects. With respect to a safe, accurate dissection, however, continuous water flow may not be suitable for intraventricular use. The authors performed experiments aimed at solving problems associated with continuous flow by using a pulsed holmium:yttrium-aluminum-garnet (Ho:YAG) laser-induced liquid jet (LILJ). They present this candidate neuroendoscopic LILJ dissection system, having examined its mechanical characteristics and evaluated its controllability both in a tissue phantom and in a rabbit cadaveric ventricle wall. METHODS: The LILJ generator was incorporated into the tip of a No. 4 French catheter so that the LILJ could be delivered via a neuroendoscope. Briefly, the LILJ was generated by irradiating an internally supplied column of physiological saline with a pulsed Ho:YAG laser (pulse duration time 350 microsec; laser energy 250-700 mJ/pulse) within a No. 4 French catheter (internal diameter 1 mm) and ejecting it from a metal nozzle (internal diameter 100 microm). The Ho:YAG laser energy pulses were conveyed by an optical fiber (core diameter 400 microm) at 3 Hz, whereas physiological saline (4 degrees C) was supplied at a rate of 40 ml/hour. The mechanical characteristics of the pulsed LILJ were investigated using high-speed photography and pressure measurements; thermal effects and controllability were analyzed using an artificial tissue model (10% gelatin of 1 mm thickness). Finally, the ventricle wall of a rabbit cadaver was dissected using the LILJ. Jet pressure increased in accordance with laser energy from 0.1 to 2 bar; this translated into a penetration depth of 0.08 to 0.9 mm per shot in the ventricle wall of the rabbit cadaver. The gelatin phantom could be cut into the desired shape without significant thermal effects and in the intended manner, with a good surgical view. CONCLUSIONS: The present results show that the pulsed LILJ has the potential to become a safe and reliable dissecting method for endoscopic procedures.     

Endotracheal tube electrodes to map and monitor activities of the vagus nerve intraoperatively. Technical note

Difficulty swallowing due to damage of the vagus nerve is one of the most devastating complications of surgery in and around the medulla oblongata; therefore, intraoperative anatomical and functional evaluation of this nerve is crucial. The authors applied endotracheal tube surface electrodes to record electromyography (EMG) activity from vocal cords innervated by the vagus nerve. The vagal nucleus or rootlet was electrically stimulated during surgery and vocalis muscle EMG activities were displayed by auditory and visual signals. This technique was used successfully to identify the vagus motor nerve and evaluate its integrity during surgery. The advantages of this method compared with the use of needle electrodes include safe simple electrode placement and stable recording during surgery. In cases involving a pontine cavernoma pressing the nucleus or a jugular foramen tumor encircling the rootlet, this method would be particularly valuable. Additional studies with a larger number of patients are needed to estimate the significance of this method as a means of functional monitoring to predict clinical function.     

Clinical study of flavor disturbance

OBJECTIVE: We have observed that, in cases of smell loss, patients often complain of taste loss as well even though they actually have normal gustatory acuity according to gustatory tests; we have defined such symptoms as "flavor disturbance". The clinical features of flavor disturbance are reported in this paper. MATERIAL AND METHODS: A total of 297 patients (99 males, 198 females; mean age 55.5 years) were treated for olfactory disturbance at the hospital of Hyogo College of Medicine between July 1995 and August 2001. Sixty-six out of 297 patients (22.5%) also experienced taste disturbance, and 49 of these 66 cases were evaluated by means of smell and taste tests. These 49 patients who complained of taste and smell loss were classified into two groups according to the results of their smell and taste tests. Patients who only complained of olfactory disturbance were also reviewed. RESULTS: There was no relationship between the severity of olfactory disturbance and the degree of flavor disturbance. The incidence of flavor disturbance was high in patients with sudden olfactory disturbance after upper respiratory tract infection or head trauma and low in those with slowly progressive olfactory disturbance. The symptoms of flavor disturbance improved regardless of whether smell was improved or not. CONCLUSIONS: The patients with flavor disturbance tended to misrecognize that they had taste loss because of sudden smell loss, and there were more of these cases than we expected. When patients with smell and taste loss are treated, flavor disturbance should also be considered.     

Identification of differentially expressed genes in salivary gland tumors with cDNA microarray

OBJECTIVE: The final goal of this study is to develop a pre-operative fine needle aspiration biopsy (FNA) diagnostic system based on gene expression profiles. As the first step to that end, the present study was performed to determine whether the cDNA microarray system is applicable for histological evaluation of parotid gland tumors. METHODS: We investigated molecular characteristics on the basis of gene expression patterns of the two most common types of salivary gland tumors (pleomorphic adenomas and Warthin tumors) and normal salivary gland tissues, using the cDNA microarray system. RESULTS: Pleomorphic adenomas and Warthin tumors can be classified by cDNA microarray. In pleomorphic adenomas, 11 independent genes were found to be up-regulated and 2 genes were down-regulated. In Warthin tumors, five independent genes were found to be up-regulated, and six genes were down-regulated. In hierarchical clustering analysis, cases were further grouped into two clusters according to the histological type. Furthermore, cDNA microarray enabled pleomorphic adenomas to be subclassified into three clusters according to the histological subtypes. CONCLUSIONS: This study suggested that cDNA microarray may be useful and applicable for the pre-operative diagnosis (such as FNA) of the salivary gland tumor.     

Transgenic mice overexpressing PACAP in pancreatic beta-cells: acute and chronic effects on insulin and glucose homeostasis

PACAP belongs to the vasoactive intestinal polypeptide (VIP)/secretin/glucagon superfamily, which also includes glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP). PACAP shares an insulinotropic property with the latter two peptides; for instance, it stimulates insulin secretion from islets in a glucose-dependent manner at femtomolar concentrations. However, the pathophysiological significance of PACAP in diabetes remains largely unknown, for several reasons, including a lack of low-molecular weight PACAP ligands and a lack of suitable animal models. As an approach to understanding PACAP's pancreatic function in vivo, we have recently generated transgenic mice overexpressing PACAP in islet beta cells under the control of human insulin promoter (Tg mice). As a consequence, it has been demonstrated that in addition to stimulating insulin secretion, PACAP has long-term effects on pancreatic endocrine cells, including proliferation of beta cells during streptozotocin-induced diabetes development as well as aging. These observations provide additional information to support the possibility that drugs associated with PACAP-signaling pathways might be of therapeutic value for the treatment of diabetes. In this review, we briefly summarize these previous studies using Tg mice and also focus on the physiological and pathophysiological roles mediated by PACAP during diabetes development.     

Twice-daily administration of a long-acting angiotensin-converting enzyme inhibitor has greater effects on neurohumoral factors than a once-daily regimen in patients with chronic congestive heart failure

Although many clinical trials have evaluated the use of long-acting angiotensin-converting enzyme (ACE) inhibitors in patients with chronic congestive heart failure (CHF), there are no data regarding whether a once-daily or twice-daily regimen is preferable with respect to effects on the neuroendocrine system. To address this issue, the authors evaluated the comparative effects of the administration schedule on neurohumoral factors and autonomic nervous activity in patients with CHF. Thirty-two patients with mild compensated CHF received lisinopril (5-20 mg/d) orally either once a day (n = 17) or twice a day (n = 15) for more than 3 months. After this initial therapy, patients receiving a once-daily regimen switched to a twice-daily regimen and vice-versa, and patients were followed for an additional 3 months. Neurohumoral factors and the coefficient of variance in the electrocardiographic R-R interval (CVRR) were measured. Hemodynamic parameters, renal function, plasma concentrations of brain natriuretic peptide and aldosterone, and CVRR did not differ between the two regimens. However, the plasma concentration of norepinephrine was significantly lower, and plasma renin activity tended to be lower with the twice-daily regimen. These findings suggest that twice-daily administration of long-acting ACE inhibitors may have better effects on the neuroendocrine system than a once-daily regimen in patients with mild CHF.