Myostatin alters glucose transporter-4 (GLUT4) expression in bovine skeletal muscles and myoblasts isolated from double-muscled (DM) and normal-muscled (NM) Japanese shorthorn cattle

The purpose of this study was to determine whether myostatin alters glucose transporter-4 (GLUT4) expression in bovine skeletal muscles and myoblasts isolated from double-muscled (DM) and normal-muscled (NM) Japanese Shorthorn cattle. Plasma concentrations of glucose were lower in DM cattle than in NM cattle (P < 0.01). The expression of GLUT4 messenger RNA (mRNA) in the skeletal muscle ex vivo and in myoblasts at 72 h after differentiation in vitro was higher in DM cattle than in NM cattle (P < 0.01). In contrast, the NM and DM cattle did not differ with respect to skeletal muscle expression of GLUT1 and myocyte enhancer factor-2c (MEF2c), a transcription factor of GLUT4. In differentiated myoblasts, the expression of GLUT1, GLUT4, and MEF2c mRNAs was greater in DM cattle than in NM cattle (P < 0.01). In the presence and absence of insulin, glucose uptake in myoblasts was increased in DM cattle relative to that of NM cattle (P < 0.01). The addition of myostatin decreased the expression of GLUT4 and MEF2c mRNAs in DM myoblasts (P < 0.05). Results of the present study suggest that myostatin inhibits the expression of GLUT4 mRNA possibly via MEF2c and that the greater ability of the DM cattle to produce muscle relative to the NM cattle may be due to their greater sensitivity to insulin and greater use of glucose.

A yeast DNA microarray for the evaluation of toxicity in environmental water containing burned ash

Numerous studies on the hazard assessment and epidemiological health responses to burned ash have been reported. However, there is little information on the potential toxicity of unknown chemical complexes in burned ash. For an overall evaluation of the multiple toxicities of burned ash, a DNA microarray was used in this study, as a new attempt to assess these toxicities. Using the global gene expression on yeast DNA chip to reflect the changes in mRNA levels, our study discovered a lot of evidences for the action of cell homeostasis and stress response etc., against the toxic effects on yeast cells. On the genes of 5,117 open reading frames (ORFs), as valid spots in a microarray, 997 were up-regulated, 1,259 were down-regulated and 2,861 remained unchanged. A detailed analysis of the microarray revealed the genes that were dynamically correlated to the function of the subcellular localization, energy/metabolism, various stress responses/cell homeostasis and detoxification. Significantly, the toxicities, caused by reactive oxygen species (ROS), metals and the other xenobiotics, were indicated in burned ash. Also, the possibility of mutagenicity of the burned ash was suggested on the basis of the DNA repair related genes.

Cloning, expression, and characterization of a family 52 beta-xylosidase gene (xysB) of a multiple-xylanase-producing bacterium, Aeromonas caviae ME-1

A lambda phage genomic library of Aeromonas caviae ME-1, a multiple-xylanase-producing bacterium, was screened for xylan degradation activities. We isolated one clone, B65, which had weak xylanase activity, by the DNS method, but gave no visible bands on zymogram assay using SDS-xylan-PAGE. Based on TLC analyses of enzymatic products and some glycosidase assays using p-nitrophenyl substrates, we established that pB65 encodes a beta-xylosidase gene. In the nucleotide sequence analysis, we found a 2190-bp open reading frame (ORF) named xysB. XysB protein is similar to some beta-xylosidases, which are categorized in the glycosyl hydrolase family 52. Another ORF (xyg), that showed similarity to the family 67 alpha-glucuronidase, was also found downstream of the xysB gene. The xysB ORF and its promoter region were cloned into the pT7-Blue vector and the transformant cells had beta-xylosidase activity. The relative molecular mass were estimated to be 75 kDa by SDS-PAGE and 159 kDa by gel filtration. These data showed that XysB has a dimeric structure of 80,697 Da subunits. This enzyme showed optimal activity at 50 degrees C and pH 6.0. It was stable below 40 degrees C and pH 5-8. The Km and Vmax were calculated to be 0.34 mM and 33 nmol x min(-1) x microg(-1), respectively. This enzyme also showed transglycosylation activity against X3 and produced X4 and X5.

Influence of Minor Dental Surgery with and without Intravenous Sedation on Levels of Hormones Responsible for Volume Homeostasis in Elderly Hypertensive Patients

Changes in the hormones responsible for volume homeostasis were observed before, during, and after minor dental surgery in 25 elderly hypertensive patients. These patients were divided into two groups. Group L patients were operated on using local anesthesia alone. Group LS patients were operated on using local anesthesia and intravenous sedation together. We found that plasma renin activity and aldosterone and vasopressin levels did not change intraoperatively in either group. We also found that intraoperative plasma human atrial natriuretic peptide (HANP) levels and systolic blood pressure were significantly elevated in group L and significantly decreased in group LS. Before local anesthesia was administered, HANP levels in both groups were already higher than the normal range in healthy adults. Therefore, these results suggest that increased HANP levels represent a compensatory response to offset further elevation of blood pressure. However, these increases did not seem to be sufficient to actually cause a decrease in blood pressure.

Rupture of flexor tendons due to pisotriquetral osteoarthritis

We are reporting a case of a flexor profundus tendon rupture of the little finger due to pisotriquetral osteoarthrosis. Resection of the pisiform bone and resurfacing of the carpal tunnel with the joint capsule was performed for the osteoarthrosis and free tendon grafting for the tendon rupture. The tendon grafting and a subsequent tenolysis restored the function of the little finger. Other than radiological changes in the pisotriquetral joint, the diagnostic value of preoperative radiocarpal arthrography was emphasized in this rare complication of pisotriquetral arthrosis.

Hydroxyapatite clay for gap filling and adequate bone ingrowth

In uncemented total hip arthroplasty, a complete filling of the gap between femoral prosthesis and the host bone is difficult and defects would remain, because the anatomy of the reamed intramedullary canal cannot fit the prosthesis. Therefore, it seems practical to fill the gap with a clay containing hydroxyapatite (HA), which has an osteoconductive character. The clay (HA clay) is made by mixing HA granules (size 0.1 mm or more) having a homogeneous pore distribution and a porosity of 35-48 vol%, and a viscous substance such as a saline solution of sodium alginate (SSSA). In the first experiment, the ratio of HA granules and sodium alginate in SSSA is set for the same handling properties of HA clay and polymethylmethacrylate bone cement (standard viscosity) before hardening. As a result, the ratio is set for 55 wt% of HA in the clay and 12.5 wt% of sodium alginate in SSSA (i.e., HA:sodium alginate:saline solution = 9.8:1:7). In the second study, the gap between the femoral stem and bone model is completely filled with HA clay. However, the gap is not filled only with HA granules or HA granules mixed with saline solution. In the third animal experiment, using an unloaded model, histology shows that HA clay has an osteoconductive property bridging the gap between the implant and the cortical bone without any adverse reaction. HA clay is considered a useful biomaterial to fill the gap with adequate bone ingrowth.

Comparison of the telescoping anastomotic technique with the end-to-end technique utilizing vein grafts for venous defects: short- and long-term results

The telescoping anastomotic technique was used for both anastomoses of vein grafts placed in the rat left epigastric vein in an effort to make the anastomosis easier and faster. Vein grafting in the right epigastric vein was completed using the conventional technique. The 20 rats with 20 left and 13 right vein grafts, which were patent at 3 weeks, were seen again 3 months postoperatively to compare the two techniques with regard to long-term stenosis and histological changes. Patency of the grafts 2 hr postoperatively was also compared between the two techniques in another 25 rats to eliminate the influence of recanalization on patency. All the vein grafts, which had been patent 3 weeks postoperatively, remained patent after 3 months and no statistically significant difference was found between the telescoping and conventional technique in the degree of stenosis. The vein grafts 2 hr postoperatively were all patent in both groups.

[The telescoping anastomotic technique: experimental efficacy for autogenous microvessel grafting]

An experimental study was performed to investigate the efficacy of the telescoping anastomotic technique for microvessel grafting. The left femoral artery was grafted into a defect in the right femoral artery in 51 rats using the telescoping technique for both the proximal and distal anastomoses. The inferior epigastric vein was grafted in situ in a further 42 rats using the same technique for both the proximal and distal anastomoses as a model of venous grafting for a venous defect. Arterial and venous grafting was performed using the conventional technique in additional rats for control purposes. The time required for anastomosis by the telescoping technique was about half that required by the conventional technique. The patency rate of the 51 arterial grafts was 51/51 (100%), and that of the 42 venous grafts was 40/42 (95.2%). In the histological examinations, the arterial grafts by the telescoping technique showed some stenosis at the site of the anastomosis at 1 week and 3 weeks postoperatively. The venous grafts, however, showed little stenosis at the site of the anastomosis at 1 and 3 weeks postoperatively. The telescoping anastomotic technique was useful for microvessel grafting and effective for saving time.

[Microbiological determination of netilmicin using a thin-layer chromatography scanner]

We presented a new colorimetric bioassay of aminoglycoside antibiotics, which were represented by netilmicin (NTL) in this study, based on the discoloration of thymolphthalein (TP) in paper (indicator-disc) by carbon dioxide produced by Bacillus subtilis. To evaluate the amount of the carbon dioxide, the following experiment was carried out. One milliliter of B. subtilis suspension containing 4.5 x 10(7) colony forming units/ml, 1 ml of nutrient broth, 0.9 ml of 0.1 M phosphate buffer (pH 8.0) and 0.1 ml NTL sample solution were added to an incubation container, which was then placed in a water-bath (37 degrees C) for 3 hours. The oxygen concentration in the head space of flask was determined using gas-chromatograph. The dose-response curves showed good correlation between amounts of NTL and carbon dioxide produced by B. subtilis. The indicator-disc containing TP and sodium hydroxide was placed into the Reacti-flask and then incubated in the same manner as described above. After incubation, concentration of blue colored TP was determined using a TLC scanner. The discoloration of blue color to white showed the proportionality between NTL concentrations and the degrees of discoloration of TP. The method can accurately measure NTL levels down to 2.5 micrograms/ml in water using 0.1 ml samples, and should be adequate for rapid bioassay.

[The factors that influence intraoperative blood loss during total hip replacement]

Fifty cases of total hip replacement performed by one surgeon were reviewed to compare the effects of epidural and general anesthesia. The blood pressure in patients under epidural anesthesia was significantly lower (P less than 0.001; t-test). There was a highly significant correlation between the operation time and the intraoperative blood loss (P less than 0.005, r = 0.67). A significant correlation was noted between the blood pressure and the minute loss of blood (P less than 0.01, r = 0.43). It is concluded that epidural anesthesia is to be recommended rather than general anesthesia in patients undergoing total hip replacement.

Responses to intravenous sedation by elderly patients at the Hokkaido University Dental Hospital

Geriatric patients who undergo intravenous sedation require careful intraoperative management, because respiratory and circulatory depression usually accompanies the administration of recommended adult sedative doses. This study examined results when a single benzodiazepine, diazepam or flunitrazepam, was carefully titrated to a clinical endpoint of conscious sedation. A total of 335 cases was divided into seven age groups. Mean sedative doses gradually decreased with age. The 60- to 69-yr group required about 75% of the adult recommended dose, the 70- to 79-yr group required 40% to 60%, and the 80- to 89-yr group required 30% to 45%. Pulse oximetry values also declined with age; respiratory depression was observed mainly in elderly patients. Declines in blood pressure after benzodiazepine administration were not correlated with age. The rise in blood pressure normally observed intraoperatively was suppressed both in young as well as old patients. We conclude that intravenous conscious sedation in elderly patients reduces stress-induced cardiovascular stimulation and that respiratory depression may occur at even low sedative doses.

Long-term histologic results of vein grafting with the telescoping anastomotic technique

We studied the long-term histologic results of a new method for autogenous vein grafting to examine whether stenosis at the anastomosis is maintained over time. Nineteen rat inferior epigastric veins were grafted into the femoral artery using a telescoping sleeve technique at both the proximal and the distal anastomoses. Specimens were studied macroscopically and histologically three months later. Stenosis at the anastomosis was located near the tip of the inserted vessel. The smallest inner diameters of the proximal and distal anastomoses were about 80% of the corresponding femoral artery diameter; no statistically significant difference was found between the two anastomoses. The grafts had a thickened wall due to intimal hypertrophy and fibrosis of the media. The inner diameter of the graft was, however, about twice that of the femoral artery, and these graft changes did not create any apparent constriction within the graft.

[Parascalene brachial plexus block]

The supraclavicular brachial plexus block originated by Kulenkampff is useful but accompanies the danger of injury to the lung, i.e. pneumothorax, because the needle is directed caudad. Reviewing the anatomy of the brachial plexus in cadavers, we have found that the parascalene brachial plexus block originated by Vongvises is safer than Kulenkampff's method. We modified this block as follows: (1) An assistant pulls lightly the affected upper extremity caudad. (2) A 23-gauge 35 mm needle is inserted at right angles to the clavicle and directed cephalad at an angle of 0-30 degrees. One hundred and eighty four ASA I and II patients were operated under this block. Their ages ranged from 11 to 77, and there were 31 patients whose cervical spinal cord had been injured. Our success rate was 92%. The only complication we encountered was Horner's syndrome which occurred in 20% of our cases. None of our patients showed clinical symptoms of pneumothorax, hematoma, epidural as well as subarachnoideal block, recurrent nerve paralysis or phrenic nerve paralysis.