Quadro-pulse stimulation is more effective than paired-pulse stimulation for plasticity induction of the human motor cortex

OBJECTIVE: Repetitive paired-pulse transcranial magnetic stimulation (TMS) at I-wave periodicity has been shown to induce a motor-evoked potential (MEP) facilitation. We hypothesized that a greater enhancement of motor cortical excitability is provoked by increasing the number of pulses per train beyond those by paired-pulse stimulation (PPS). METHODS: We explored motor cortical excitability changes induced by repetitive application of trains of four monophasic magnetic pulses (quadro-pulse stimulation: QPS) at 1.5-ms intervals, repeated every 5s over the motor cortex projecting to the hand muscles. The aftereffects of QPS were evaluated with MEPs to a single-pulse TMS, motor threshold (MT), and responses to brain-stem stimulation. These effects were compared to those after PPS. To evaluate the QPS safety, we also studied the spread of excitation and after discharge using surface electromyograms (EMGs) of hand and arm muscles. RESULTS: Sizes of MEPs from the hand muscle were enhanced for longer than 75min after QPS; they reverted to the baseline at 90min. Responses to brain-stem stimulation from the hand muscle and cortical MEPs from the forearm muscle were unchanged after QPS over the hand motor area. MT was unaffected by QPS. No spreads of excitation were detected after QPS. The appearance rate of after discharges during QPS was not different from that during sham stimulation. CONCLUSIONS: Results show that QPS can safely induce long-lasting, topographically specific enhancement of motor cortical excitability. SIGNIFICANCE: QPS is more effective than PPS for inducing motor cortical plasticity.     

A 5-year-old patient with allergic diseases responsive to stellate ganglion block]

We examined a 5-year-old boy with allergic rhinitis, chronic sinusitis, atopic dermatitis, and tendency to suffer common cold, who responded to stellate ganglion block (SGB). SGB therapy was extremely effective for this patient. The result suggests that SGB therapy should be performed on patients with allergic diseases resistant to drug and diet therapy. Furthermore, the indication for nerve block therapy, such as SGB, may be extended even to pediatric patients.     

Clinical assessment of pancreatic diabetes caused by chronic pancreatitis

Despite the high prevalence of diabetes mellitus in patients with chronic pancreatitis, few studies of pancreatic diabetes have been reported. We investigated 154 patients with chronic pancreatitis, of whom 50% were diabetics, with special reference to the features and clinical course of pancreatic diabetes. We arrived to clarify the features of pancreatic diabetes by comparing pancreatic exocrine function in 112 patients with primary diabetes with findings in a separate group of 80 patients with chronic pancreatitis. Pancreatic diabetes is proposed as a type of diabetes in which exocrine pancreatic function is markedly decreased. Progressive and fatal angiopathies were found in patients with pancreatic diabetes after a long duration of diabetes. The present investigation suggests that treatment of malnutrition is necessary in patients with pancreatic diabetes and that control of blood glucose is often difficult in these patients because of the high incidence of insulin-induced hypoglycemic episodes. (Received Feb. 6, 1997; accepted July 25, 1997)     

Treatment strategies for hepatic metastasis from colorectal cancer

Hepatic micrometastases of the parenchyma adjacent to a macroscopic lesion were detected in 17 of 31 resected liver metastases. Fifty-nine micrometastatic lesions were detected in total; 26 lesions were situated in the portal vein (PV), 22 in the central vein (CV), 5 in the bile duct (BD), and 6 in the sinusoid (SS). A histological study confirmed the direct invasion of the macrometastatic cancer cells into the adjacent PV, CV, BD, and SS. According to the tumor doubling time, the mean diameter of the macrometastases in 19 remnant livers was calculated to have been 0.57±0.87 cm at the time of the primary resection. The calculated diameter of 3 of these 19 macrometastases was found to be less than 0.01 cm, the minimum implantable size, indicating that the cancer recurrence in these specimens may have developed from macroscopic metastatic lesions as a satellite, and not from the primary tumor. In 13 patients who received doses of 5250 mg or more of 5 fluorouracil (FU) via the hepatic artery, the cumulative disease-free rate 2 years postoperatively was 100%; this value was 47.6% in 11 patients who received less than 5250 mg of 5 FU via the hepatic artery, and 0% in 39 patients who received no chemotherapy (P<0.005). These results suggest that anatomical hepatic resection for satellite lesions, combined with prophylactic hepatic arterial chemotherapy for micrometastases, decreases the recurrence rate of hepatic metastases in the remnant liver.     

Clinical and fundamental studies on intravenous drip infusion of gentamicin in the pediatric field. Pediatric study group of gentamicin

A multiclinic study of gentamicin (GM) given by intravenous drip infusion was carried out by the Gentamicin Pediatric Study Group. The results are summarized as follows: 1. Upon intravenous drip infusion of GM at a dose range of 2.0-2.5 mg/kg over a period of 0.5-1 hour, therapeutically effective serum concentrations of 4-12 micrograms/ml were obtained. These values are similar to reported values in previous studies using GM intramuscular injection. 2. High urinary concentrations were observed up to 6 hours after administration, and the urinary recovery rate was approximately 60%. 3. Of a total of 142 cases collected, 117 cases were evaluated. Efficacy rates by diseases were: 100% in pneumonia (30/30), 98.3% in urinary tract infections (59/60), and 92.3% in other infections (skin and soft tissue) (12/13), with an overall efficacy rate of 94.9% (including 77 "excellent" cases). 4. Bacteriological examinations showed high eradication rates with the use of GM; i.e., 80% with Staphylococcus aureus (8/10), 60% with Pseudomonas aeruginosa (3/5), 100% with Haemophilus influenzae (7/7) and 97.8% with Escherichia coli (44/45), achieving an overall eradication rate of 92.4%. In mixed infections, the eradication rate was 85.7% (6/7). 5. No ototoxicity, nephrotoxicity or allergic reactions was observed. Abnormal laboratory findings observed were: GOT elevation in 3.1% of cases, GPT elevation in 3.9%, platelet increase in 1.5% and eosinophil increase in 0.8%, thus an overall rate of the appearance of abnormality was 5.6%. The above results indicate that an intravenous drip infusion of GM is a useful method for treating infections in pediatrics.     

Dynamic analysis of secretagogue-induced amylase secretion from rat pancreatic acini studied by perifusion system

A perifusion system was applied for the study on stimulus-enzyme secretion coupling in dispersed pancreatic acini. The system is highly simple, preserves the acini up to more than 3 hr, and makes feasible clear-cut examination on the time course of enzyme secretion caused by secretagogues. Caerulein (10(-9) M) and carbamylcholine (10(-5) M) caused a biphasic amylase secretory pattern consisting of an initial burst secretion and a sustained one. Caerulein induced a persistent amylase release even after cessation of the stimulation, while carbamylcholine-stimulated amylase release returned to basal levels. Atropine inhibited completely carbamylcholine-stimulated amylase release and the successive stimulation by caerulein evoked the amylase secretion with a decreased initial burst secretion. In calcium free medium, caerulein and carbamylcholine induced only a slight secretion, particularly in the sustained secretion phase and a gradual increase occurred with the addition of calcium.     

Changes in fibre-type composition and myosin heavy-chain IId isoform in rat soleus muscle during recovery period after hindlimb suspension

We examined the changes in myosin heavy-chain (HC) isoforms and fibre-type composition in rat soleus muscle using both myosin adenosine triphosphatase staining and sodium dodecyl sulphate/polyacrylamide gel electrophoresis (SDS-PAGE) analyses during the recovery period after 4 weeks of hindlimb suspension. Although there was no change in type IIc fibres after the suspension, an increase in this type of fibres was observed during the 1- to 4-week recovery period. The increase in type Ilc fibres was considered to be due to a shift from type Ila to IIc fibres. The SDS-PAGE analysis revealed the presence of the HC IId isoform, which was not observed in the control muscle, after a 4-week hindlimb suspension. The HC IId isoform gradually decreased over 3 weeks of recovery and disappeared in the 4th week of recovery after the suspension. These results suggest that the hypogravity conditions induced by hindlimb suspension stimulated the synthesis of the HC IId isoform, whereas an increase in mechanical load to the muscle accelerated the degradation of the HC IId isoform and the synthesis of type Ilc fibres during the recovery period after hindlimb suspension.     

Split tolerance between spleen and lymph node cells in severe combined immunodeficiency mice grafted with AKR fetal liver cells

Severe combined Immunodeficient (SCID) mice defective in stemcells for T and B cells appear to be an ideal host for constructionof chimeric mice. When bone marrow cells are used as a sourceof stem cells, however, host SCID mice do not always show sufficientreconstitutlon. In this study, fetal liver cells from AKR embryoswere transplanted into SCID mice without prior irradiation.This treatment induced full reconstltution of lymphopoiesisas evaluated by flow cytometry analysis and serum Ig production2 months after transplantation. Thus, fetal liver cells seemto be a better source for reconstitutlon of SCID mice than bonemarrow cells. Lymph node (LN) cells of these mice (FLT mice)had no proliferatlve or cytotoxlc activities against eitherhost-type (C.B-17) or donor-type (AKR) spleen cells. However,spleen cells from FLT mice exhibited marked proliferatlve andcytotoxlc activities against C.B-17 cells, with no activitiesagainst AKR cells. Spirt tolerance against C.B-17 cells In spleenand LN cells was not a transient phenomenon, since similar resultswere obtained from a cytotoxic T lymphocyte assay 4 months later.In spite of the strong host reactivity in vitro, aberrationof clonal deletion or development of a graft-versus-host diseasewas not seen in FLT mice. As IL-2 induced the host reactivityof LN cells in a mixed lymphocyte reaction, potentially host-reactiveT cells were present in LN but were rendered anerglc. Tolerancein FLT mice seems to be regulated by a peripheral mechanism.We supposed that the split tolerance in FLT mice was inducedby the different antigenicity between the spleen and LN.     

Analysis of human rotavirus strains prevailing in Bangladesh in relation to nationwide floods brought by the 1988 monsoon.

The virologic character of human rotavirus strains prevailing in Bangladesh was investigated in relation to the devastating nationwide floods brought by the 1988 monsoon. Human rotaviruses contained in stool specimens that were collected from inpatients with infantile and adult diarrhea in two hospitals in Mymensingh over a 13-month period (January 1988 to January 1989) and in one hospital in Dhaka over a 3-month period (February to April 1988) were examined for their subgroup, VP7 serotype, and RNA electropherotype. In concurrence with the spread of the flood (from the middle of August 1988), the number of infantile and adult diarrhea patients increased greatly. At the same time, the proportion of rotavirus-positive specimens in all diarrhea cases also increased remarkably, reaching 54 and 45% in September and October, respectively. An electrophoretic analysis of viral RNA revealed 17 distinct patterns of viral RNA (14 long and 3 short electropherotypes) and a considerable number of mixed electropherotypes, suggesting the simultaneous infection of some patients with more than two rotavirus strains. It was noteworthy that electropherotypes of rotavirus strains prevailing in the community changed considerably after the spreading of the flood and that the frequency of virus specimens showing mixed electropherotypes increased significantly during the flood period. These results suggest that sudden environmental change caused by the devastating floods seriously affected the epidemiology of rotavirus infections by increasing the opportunity of transmission of the virus and by reducing the resistance of the host to infection. In both pediatric and adult patient groups, serotypes 1 and 2 were the most frequent ones detected, followed by serotype 4.(ABSTRACT TRUNCATED AT 250 WORDS)