In vitro evaluation study of the membrane autotransfusion system experimental prototype: MATS-I

Abstract: Membrane Autotransfusion System (MATS) utilizing plasmapheresis technology has been developed in our laboratory. A specially designed polyethylene hollow fiber membrane was utilized. This study was conducted to evaluate performance of the first experimental prototype, MATS-I. The results of this study showed that the MATS-I could concentrate diluted blood at 10% of the initial hematocrit concentration (HCTi) into over 40% after passing through the system at a transmembrane pressure of 70 mm Hg. Moreover, the MATS-I can continuously treat 10,000 ml of diluted blood at various HCTi levels without deteriorating its performances. Even though the MATS-I met all required performances as an autotransfusion system, several areas of improvement of the system were necessary to meet various clinical needs. The next prototype, MATS-II, can be designed based on experiences obtained from the MATS-I. The MATS is smaller, more atraumatic and continuous, and is a faster system when compared to the currently available centrifugal autotransfusion devices.     

Determination of ABO genotypes with DNA extracted from formalin-fixed,paraffin-embedded tissues

Summary The gene encoding the specific glycosyltransferases which catalyze the conversion of the H antigen to A or B antigens shows a slight but distinct variation in its allelic nucleotide sequence and can be divided into 6 genotypes when digested with specific restriction enzymes. We extracted DNA from formalin-fixed, paraffin-embedded tissues using SDS/proteinase K treatment followed by phenol/chloroform extraction. The sequence of nucleotides for the A, B and O genes was amplified by the polymerase chain reaction (PCR). DNA fragments of 128 by and 200 by could be amplified in the second round of PCR, using an aliquot of the first round PCR product as template. Degraded DNA from paraffin blocks stored for up to 10.7 years could be successfully typed. The ABO genotype was deduced from the digestion patterns with an appropriate combination of restriction enzymes and was compatible with the phenotype obtained from the blood sample.     

Nicotinamide inhibits sodium-dependent phosphate cotransport activity in rat small intestine.

BACKGROUND: We recently reported that the administration of niceritorol (a nicotinic acid derivative which improves lipid metabolism and peripheral circulation, and is used for the treatment of hyperlipidaemia and impaired peripheral circulation) to patients with hyperphosphataemia undergoing dialysis decreased the serum phosphate (Pi) concentration. We found that this was due to an acceleration of faecal Pi excretion by niceritrol. METHODS: Intestinal brush border membrane vesicles (BBMVs) were prepared from rat jejunum, and the Na+-dependent and Na+-independent Pi transport activities in these vesicles were measured. In addition, the functional Pi transporter from rat small intestine was injected in Xenopus oocytes, and the effect of nicotinamide on the levels of its expression were measured by northern blotting. RESULTS: The Na+-dependent component was significantly decreased in the BBMVs isolated from rats treated with nicotinamide, while the Na+-independent component was not changed. Kinetic studies demonstrated that the decreased activity was due to reduction of the Vmax value and not an elevation of the Km values. When poly(A)+RNA from rats treated with nicotinamide was microinjected into Xenopus oocytes, the Pi transport activity was significantly decreased compared with that in the control animals. In addition, there were no significant changes in Na/Pi cotransporters and activators, but the vitamin D receptor mRNA level was reduced to 80% of the control level. CONCLUSIONS: These observations suggest that nicotinamide may regulate the expression of a major functional Na/Pi cotransporter in the rat small intestine.     

Embolic myocardial infarction and left ventricular rupture due to mitral valve endocarditis.

A left ventricular rupture due to embolic myocardial infarction is extremely rare. A 72-year-old woman developed an acute embolic myocardial infarction and mitral regurgitation due to infective endocarditis. Two days after the infarction, a left ventricular free wall rupture occurred after transesophageal echo examination. She received an epicardial patch and mitral valve replacement. Perioperatively, an intra-aortic balloon pump and long-term antibiotics were used. The postoperative course was uneventful, and she is doing well 10 months after surgery.     

Extraanatomic aortic bypass for repair of aortic coarctation

We describe two adult patients who underwent extraanatomic ascending aorta-to-descending thoracic aorta bypass grafting for repair of aortic coarctation through a median sternotomy and posterior pericardial approach. Of the two patients, one presented with coarctation and concurrent cardiovascular disorders, and the other, with residual coarctation. Cardiopulmonary bypass was established with double arterial cannulation in the aorta or axillary artery and the femoral artery ensure adequate perfusion proximal and distal to coarctation and bicaval cannulation. The heart was retracted cephalic and superiorly, and the descending thoracic aorta was exposed through the posterior pericardium. After achieving distal anastomosis, the graft was directed anterior to the inferior vena cava and lateral to the right atrium, and anastomosed to the right lateral aspect of the ascending aorta. A 14-mm graft was used. In one patient receiving concomitant procedures, mitral valve repair and replacement of the ascending aorta was performed after the distal anastomosis.     

The UPAO test in preoperative evaluation for major pulmonary resection: an operative case with markedly improved ventilatory function after radical pulmonary resection for lung cancer associated with pulmonary emphysema.

A 65-year-old man was admitted to our hospital for treatment of a squamous cell carcinoma in his right lung. Respiratory function testing showed an extremely reduced forced expiratory volume in 1 second (FEV1) of 1.0 l (29.9% of predicted), and a reduced FEV1/FVC ratio of 24.1%. Arterial blood gases on room air showed a pH of 7.41, a PaCO(2) of 36.7 mmHg, and a PaO(2) of 79.3 mmHg. To assess the predictive postoperative cardiopulmonary function, unilateral pulmonary artery occlusion (UPAO) testing was performed. In the condition of right main PA occlusion, the mean pulmonary artery pressure (mPAP), cardiac index (CI) and total pulmonary vessel resistance index (TPVRI) was 18 mmHg, 3.2 l/min/m(2) and 443.37 dyne.sec.cm(-5)/m(2), respectively. He underwent a middle lobectomy with combined partial resection of both the upper and lower lobes. He also underwent simultaneous resection of a giant bulla arising from the right upper lobe as lung volume reduction surgery. At 80 days after the operation, his FEV1 rose to 1.88 l, and the PaO(2) on room air was improved to 88.9 mmHg. UPAO testing was suggested to be more useful than routine pulmonary function test to determine the accurate predictive postoperative cardiopulmonary function and to decide indication for a radical operation.     

Laparoscopic rectal surgery for middle and lower rectal cancer

Background  

The usefulness of laparoscopic low anterior resection for middle and lower rectal cancer remains controversial.     

Current status of hip bone densitometry in Japan: a nationwide survey

Hip fracture greatly impairs quality of life in patients with osteoporosis. Measurement of bone mineral density (BMD) in the hip, which is closely related to fracture risk, is therefore diagnostically important. Furthermore, since in some elderly individuals lumbar BMD may be overestimated because of vertebral fracture or spondylosis deformans, measurement of hip BMD is also important. However, hip BMD is unlikely to be measured as often as lumbar BMD in Japan. A questionnaire survey was conducted to determine how many institutions measure hip BMD. A total of 861 institutions responded to the survey, 596 (69%) of which performed hip bone densitometry. The number of such institutions per million population was calculated to be 4.7. Measurement of hip BMD was more frequent in university hospitals than in general hospitals, clinics, and non-medical institutions. Furthermore, 298 (51%) of 590 institutions measured hip BMD in more than 75% of all bone densitometry examinees. This is the first report on the current status of utilization of hip bone densitometry in Japan.