Compound muscle action potentials during repetitive nerve stimulation

When using repetitive nerve stimulation to examine neuromuscular transmission, the change in compound muscle action potential (CMAP) size is usually assessed by measurement of negative-peak or peak-to-peak amplitude. Technological developments now allow automatic measurement of CMAP area, but some patients show increment of CMAP amplitude and decrement of CMAP area. This study systematically analyzed the changes in these CMAP parameters in 23 neurologically healthy subjects. CMAPs were recorded when the ulnar nerve was stimulated at frequencies of 1, 2, 5, 10, 20, 30, and 50 HZ (five pulses per train). CMAP amplitude showed significant increment within a train when stimulus frequency was above 5 HZ (probably due to increased muscle-fiber conduction velocity), whereas CMAP area hardly changed at any frequencies. Measurement of CMAP area produces less ambiguous results than amplitude measurement in repetitive nerve stimulation studies.     

Neural precursor cells derived from human embryonic brain retain regional specificity

Recent studies have revealed that neural precursor cells can be expanded not only from the subventricular zone and hippocampus but also from other regions of the human embryonic brain. To determine the regional differences of these precursor cells, we divided the brain of a 9-week-old human embryo into four parts, i.e., telencephalon, diencephalon, mesencephalon, and rhombencephalon. All cultures of the tissues yielded neurospheres, and these spheres gave rise to neurons, astrocytes, and oligodendrocytes. An analysis of clonal populations revealed that these precursor cells were multipotent, and two region-specific differences in neural precursor cells were revealed: 1) The precursor cells from the rostral part of the brain tended to proliferate faster than those from the caudal part, and 2) the precursor cells from the diencephalon and mesencephalon gave rise to more tyrosine hydoxylase (TH)-positive neurons than those from the telencephalon and rhombencephalon. When 50-day-cultured spheres were caused to differentiate, the percentage of TH-positive cells per total cell population was 1.2% for diencephalic and mesencephalic precursors, whereas it was 0.4% for telencephalic and rhombencephalic ones. Furthermore, the TH-positive cells from diencephalic and mesencephalic precursors were large, multipolar, and gamma-aminobutyric acid (GABA)-negative, which suggested that these cells were midbrain dopaminergic neurons. In contrast, TH-positive cells from telencephalic and rhombencephalic precursors were small, bipolar, and GABA-positive. These results suggest that human neural precursor cells might have the potential to differentiate into a variety of cells but retain regional specificity.     

Dysgerminoma in a patient with a tumor of the neck. Empiric treatment of stage IV dysgerminoma

The evolution of therapy for malignant ovarian germ cell tumors is one of the true success stories in oncology. Treatment outcome has improved greatly thanks to cisplatin-based combination chemotherapy. According to the well-established treatment guidelines for advanced cases, we treated a case of stage IV undifferentiated germ cell tumor in which we were able to preserve the patient's fertility. We concluded that the PEP regimen is an effective treatment for the patient with metastatic germ cell tumor.     

Expression of MUC5AC and MUC6 in invasive ductal carcinoma of the pancreas and relationship with prognosis

Aim/Background. MUC5AC and MUC6 are two major types of mucin that are abundantly present in the stomach; both of them form a gel of high viscosity that provides protection and lubrication. Expressions of MUC5AC and MUC6 are seen in pancreatic neoplasms, whereas the relationships between MUC5AC/MUC6 expression and clinicopathological factors and patient prognosis in invasive ductal carcinoma (IDC) of the pancreas have not been investigated. The aim of this study was to investigate MUC5AC and MUC6 expressions in IDC with special reference to clinicopathological factors and patient prognosis. Methods. Tissue samples were taken from 33 patients with IDC of the pancreas after radical surgical treatment. MUC5AC and MUC6 expressions were examined immunohistochemically. Results. The expressions of MUC5AC and MUC6 were observed in the cytoplasm of the tumor cells. MUC5AC and MUC6 immunoreactivities in the cancer tissues were found in 21 (63.6%) and 15 (45.5%) of 33 cases of IDC of the pancreas, respectively. MUC5AC-negative expression was associated significantly with lymphatic invasion, venous invasion, lymph node metastasis, and MUC5AC-positive patients showed significant better survival than those MUC5AC-negative patients. MUC6 expression was significantly related to tumor location, whereas MUC6 expression did not show significant relationship with patient survival. Conclusion. The results indicate that MUC5AC expression plays an important role in impacting tumor progression in IDC of the pancreas. MUC5AC expression is a benefit to better survival of patients with IDC of the pancreas. MUC6 expression is not involved in tumor progression in IDC of the pancreas.     

Interstitial Deletion of the Long Arm of Chromosome 8 without Langer-Giedion Syndrome

Abstract: A case of interstitial deletion of the long arm of chromosome 8 is reported. A chromosome analysis by a high resolution banding revealed the abnormal karyotype, 46, XY, del (8) (qll.2ql3). Although some reports describe an association of 8q deletion with the Langer-Giedion syndrome, this patient did not have the typical features of this syndrome. It was noted that the patient had amino aciduria, EEG and ECG abnormalities together with other pathological findings.     

The neurobiological approaches to obsessive-compulsive disorder]

The lifetime prevalence rate of obsessive-compulsive disorder (OCD) is more than 2 percent of the population. Its contemporary pathophysiological models have been explored. As serotonin reuptake inhibitors and cognitive behavior therapy are both considered first-line treatments of OCD, the treatment interventions provide us with clues. In this review, the authors summarized that genetics, neuropathology in the cortico-striatal-thalamic-cortical (CTSC) circuits, the association between OCD and Tourette's syndrome, the possibility of autoimmune-mediated pathophysiology containing PANDAS, serologic surveys of patients, and animal models including transgenic mice. Further research, genetic, neuroimmunological, and neuroimaging works may ultimately be useful in developing new treatments of OCD.     

Serial Polysomnograms in Creutzfeldt-Jakob Disease

Abstract: This is a report of the case of a patient with Creutzfeldt-Jakob disease, whose electroencephalograms and polysomnograms were repeatedly recorded throughout the course of the illness with details of the alterations of periodic synchronous discharges. In the advanced stage of the disease, the appearance of peculiar paroxysms was noted, predominantly in the early morning. Furthermore, apnea of the central type was observed during the same time period. Discussions were held on the mechanisms inducing the EEG paroxysms and apneas.