Vermis lesions in acute cerebellar ataxia: a sequential imaging study

We report a case of acute cerebellar ataxia (ACA) with discrete paleocerebellar clinical symptoms who underwent serial cranial magnetic resonance images not only with conventional spin echo sequences but also fluid attenuated inversion recovery (FLAIR) sequences. The images with the latter sequences demonstrated more conspicuously the high signal intensity lesions in the superior cerebellar vermis and cerebellar peduncle than those with the former sequences. In the convalescent phase, the lesions became markedly atrophic. Thus, the causative lesions for ACA were demonstrated on MRI, and FLAIR provided clear images of the lesion in the vermis.     

The effect of adjuvant therapy with or without tamoxifen on the endocrine function of patients with breast cancer

The ovarian and pituitary functions of 64 operable breast cancer patients undergoing adjuvant therapy with cytotoxic chemotherapy and/or tamoxifen were investigated. The post menopausal patients, divided into 3 treatment groups, one with tamoxifen alone, one with tamoxifen and chemotherapy and the other with chemotherapy alone had serum estradiol 17-β (E2) and progesterone levels lower than the evaluable limits. Although there was no significant difference in the level of estrone sulfate (E1-S) between these three groups, the level of lutainizing hormone (LH) and follicle stimulating hormone (FSH) in the patients treated with tamoxifen alone and tamoxifen and chemotherapy were significantly lower than those treated with chemotherapy alone. The decrease in gonadotropin levels induced by tamoxifen treatment was reversible as it appeared after the initiation of tamoxifen and recovered after its cessation. In the premenopausal patients, a group treated with tamoxifen and chemotherapy had significantly higher E1-S, E2 and progesterone levels and significantly lower gonadotropin levels than a group treated with chemotherapy alone or one treated with a cyclophosphamide regimen. These increases in the levels of estrogen and progesterone were also reversible, and induced by tamoxifen. Thus, adjuvant endocrinochemotherapy causes profound alteration in the hypothalamo-pituitary-ovarian axis and therefore, monitoring a variety of hormonal levels is thought to be necessary for assessing the consequences of adjuvant therapy in breast cancer patients, especially in premenopausal patients using tamoxifen.     

Papillo-Choledochectomy in the Operative Management of Mucosal Neoplasms of the Periampullary Region

Two patients with mucosal cancer of the periampullary region were treated with papillocholedochectomy, which entails removal of the papilla of Vater and the whole length of the common bile duct. The neoplasm is dissected out through the plane between the duodenal circular and longitudinal muscles, deep to the sphincter of Oddi and the fibromuscular layer of the bile duct. Pathological examination showed that cancer was confined to the mucosal layer without stromal invasion, and that the operation achieved radical cure. For mucosal cancer, papillo-choledochectomy is an alternative to pancreatoduodenectomy, provided that repeated frozen-section studies confirm the completeness of excision.     

Thyroplasty Type I with Ceramic Shim

Abstract: To prevent side effects from a silicone shim in Isshiki thyroplasty type I, we used a ceramic shim in 10 patients with unilateral recurrent laryngeal nerve paralysis. No published reports have described the use of ceramic in this type of surgery. According to the degree of glottic insufficiency, ceramic shims of various heights were inserted into the fenestration made in the thyroid ala. All patients experienced subjective improvement of voice postoperatively. Laryngoscopies in most cases showed that glottic insufficiency improved postoperatively. In the postoperative examination, the maximum phonation time improved an average of 3.7 s, and the mean flow rate improved an average of 331 ml/s. We have analyzed the relationship of these improvements to the degree of glottic insufficiency and have compared our results with those of other investigators.     

Pharmacology of glutamate neurotoxicity in cortical cell culture: attenuation by NMDA antagonists

The antagonist pharmacology of glutamate neurotoxicity was quantitatively examined in murine cortical cell cultures. Addition of 1-3 mM DL-2-amino-5-phosphonovalerate (APV), or its active isomer D-APV, acutely to the exposure solution selectively blocked the neuroexcitation and neuronal cell selectively blocked the neuroexcitation and neuronal cell loss produced by N-methyl-D-aspartate (NMDA), with relatively little effect on that produced by either kainate or quisqualate. As expected, this selective NMDA receptor blockade only partially reduced the neuroexcitation or acute neuronal swelling produced by the broad-spectrum agonist glutamate; surprisingly, however, this blockade was sufficient to reduce glutamate-induced neuronal cell loss markedly. Lower concentrations of APV or D-APV had much less protective effect, suggesting that the blockade of a large number of NMDA receptors was required to acutely antagonize glutamate neurotoxicity. This requirement may be caused by the amplification of small amounts of acute glutamate-induced injury by subsequent release of endogenous NMDA agonists from injured neurons, as the "late" addition of 10-1000 microM APV or D-APV (after termination of glutamate exposure) also reduced resultant neuronal damage. If APV or D-APV were present both during and after glutamate exposure, a summation dose-protection relationship was obtained, showing substantial protective efficacy at low micromolar antagonist concentrations. Screening of several other excitatory amino acid antagonists confirmed that the ability to antagonize glutamate neurotoxicity might correlate with ability to block NMDA-induced neuroexcitation: The reported NMDA antagonists ketamine and DL-2-amino-7-phosphono-heptanoate, as well as the broad-spectrum antagonist kynurenate, were all found to attenuate glutamate neurotoxicity substantially; whereas gamma-D-glutamylaminomethyl sulfonate and L-glutamate diethyl ester, compounds reported to block predominantly quisqualate or kainate receptors, did not affect glutamate neurotoxicity. The present study suggests that glutamate neurotoxicity may be predominantly mediated by the activation of the NMDA subclass of glutamate receptors--occurring both directly, during exposure to exogenous compound, and indirectly, due to the subsequent release of endogenous NMDA agonists. Given other studies linking NMDA receptors to channels with unusually high calcium permeability, this suggestion is consistent with previous data showing that glutamate neurotoxicity depends heavily on extracellular calcium.     

Evaluation of nicotine,cotinine, thiocyanate,carboxyhemoglobin, and expired carbon monoxide as biochemical tobacco smoke uptake parameters

Summary In a cross-sectional study on 236 individuals in Japan (174 males, 62 females; 149 smokers, 87 non-smokers) plasma nicotine (pnic), cotinine (pcot) and thiocyanate (pSCN), urinary creatinine ratios of nicotine (unic), cotinine (ucot) and thiocyanate (uSCN) as well as carboxyhemoglobin (COHb) and expired carbon monoxide (COex) were determined. All tobacco smoke uptake parameters (TSUP) were significantly elevated in smokers as compared to non-smokers. The discriminant power (smokers vs non-smokers) rank in the following order: ucot pcot unic > pSCN COHb pnic > COex uSCN. All parameters except for pnic are significantly correlated with the self-reported number of cigarettes smoked per day. The reason for the poor correlation of pnic with daily cigarette consumption is the short half-life of pnic coupled with the arbitrary time of blood drawing in relation to the last time of smoking.Dr. Muranaka, the chief author of this paper, was the director of our hospital. He died suddenly on 18 April 1986. This article is therefore the last monument to be planned and achieved under the late Dr. Muranaka's direction.     

A new closed-system using partially frozen injectate for thermodilution cardiac output determinations

The FI (partially frozen injectate) system, a new closed-system devised by the authors for thermodilution cardiac output determinations, has two major features: 1) it needs no ice-filled receptacle to keep injectate cold because it uses partially frozen injectate, and 2) it can go without monitoring the injectate temperatures during the whole process of cardiac output determinations. The author evaluated the accuracy and reproducibility of cardiac output determinations with the FI system in 10 critically ill patients, as compared with another closed-system (which is commercially available) and the standard open method. The injectate temperatures in the FI system were also measured in vitro. The mean injectate temperature in the FI system was 0.71 ± 0.26°C and 80% of the injectate temperatures were lower than 1.0°C. Even when no monitoring of injectate temperatures was made, the predicated error in the calculated cardiac output resulted as low as 2% with the FI system. The mean cardiac output values were not statistically different between the FI system and the other two systems.(Maruta H, Usuda Y, Okutsu Y et al.: A new closed-system using partially frozen injectate for thermodilution cardiac output determinations. J Anesth 3: 35–39, 1989)     

Comparison of the biomechanical effect of posterior condylar offset and kinematics between posterior cruciate-retaining and posterior-stabilized total knee arthroplasty

Background

The effect of the changes in the femoral posterior condylar offset (PCO) on anterior–posterior (AP) translation and internal–external (IE) rotation in cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) remains unknown. The purpose of this study was to compare the kinematics in CR and PS TKA with respect to the difference in prosthetic design and PCO change through a computational simulation.

Control of Mammalian Cell and Bacteria Adhesion on Substrates Micropatterned with Poly(ethylene glycol) Hydrogels

A simple method for controlling the spatial positioning of mammalian cells and bacteria on substrates using patterned poly(ethylene glycol) (PEG) hydrogel microstructures is described. These microstructures were fabricated using photolithography on silicon, glass or poly (dimethylsiloxane) (PDMS) surfaces modified with a 3-(trichlorosilyl) propyl methacrylate (TPM) monolayer. During the photogelation reaction, the resulting hydrogel microstructures were covalently bound to the substrate via the TPM monolayer and did not detached from the substrate upon hydration. For mammalian cell patterning, microwell arrays of different dimensions were fabricated. These microwells were composed of hydrophilic PEG hydrogel walls surrounding hydrophobic TPM floors inside the microwells. Murine 3T3 fibroblasts and transformed hepatocytes were shown to selectively adhere to the TPM monolayer inside the microwells, maintaining their viability, while adherent cells were not present on the hydrogel walls. The number of cells inside one microwell could be controled by changing the lateral dimension of the microwells, thus allowing only a single cell per microwell if desired. In the case of 30×30 m microwells, as many as 400 microwells were fabricated in 1 mm². In addition, PEG hydrogel microstructures were also shown to effectively resist the adhesion of bacteria such as Escherichia coli.