The preparation of three new types of phenylboronic acid derivatives and their evaluation as enhancers on the luminol-H(2)O(2)-horseradish peroxidase (HRP) chemiluminescence (CL) reaction are described. After optimizing the CL reaction conditions, the CL system was applied to the HRP determination. Among the three phenylboronic acid derivatives, i.e. 4-(4, 5-diphenyl-1H-imidazol-2-yl)phenylboronic acid (DPA), 4-[4(or 5)-(4-dimethylaminophenyl)-5(or 4)-phenyl-1H-imidazol-2-yl]phenylboronic acid (DAPA) and 4-[4, 5-di(2-pyridyl)-1H-imidazol-2-yl]phenylboronic acid (DPPA), DPPA was found to be the most potent enhancer. The sensitivity obtained with DPPA was about 180 times higher than that without an enhancer. The detection limit of HRP obtained with DPPA was 0.15 ng/assay (ca. 3.5 fmol), which is comparable to that with 4-iodophenol under the conditions examined. All the phenylboronic acid derivatives examined had the effect of prolonging light emission compared to 4-iodophenol.

Boronic Acids↗

PubMedDate not supplied

Peroxyoxalate chemiluminescent assay for oxidase activities based on detecting enzymatically formed hydrogen peroxide.

A sensitive peroxyoxalate chemiluminescent (PO-CL) assay for activities of oxidases (uricase, choline oxidase, cholesterol oxidase and xanthine oxidase) which catalyse a formation of hydrogen peroxide was developed using 4,4'-oxalyl- bis[(trifluoromethyl-sulphonyl)imino]trimethylene-bis(4- methylmorpholinium)trifluoromethanesulphonate as a chemiluminogenic reagent and 2,4,6,8-tetramorpholinopyrimido[5,4- d]pyrimidine as fluorophore. The standard curve for hydrogen peroxide was linear over the range 1 x 10(-7)-1 x 10(-4) mol/L. Relative standard deviations for oxidase assays were 5.1-12.7% (n = 10). Detection limits were 1 x 10(-3) U/mL for uricase, 5 x 10(-4) U/mL for choline oxidase, 5 x 10(-3) U/mL for cholesterol oxidase and 5 x 10(-4) U/mL xanthine oxidase (sample to blank ratio, 3).

Alcohol Oxidoreductases↗

PubMedDate not supplied

Application of an enhanced luminol chemiluminescence reaction using 4-[4,5-di(2-pyridyl)-1H-imidazol-2-yl]phenylboronic acid to photographic detection of horseradish peroxidase on a membrane.

Photographic detection of horseradish peroxidase (HRP) on a membrane by the luminol-hydrogen peroxide-HRP chemiluminescence reaction using 4-[4,5-di(2-pyridyl)-1H-imidazol-2-yl]phenylboronic acid (DPPA) as an enhancer is described. The method is based on the long-lived chemiluminescence emission obtained by using DPPA. Under the optimum conditions, as little as 0.10 ng (ca. 2.3 fmol) and 0.20 ng (ca. 4.6 fmol) per spot of HRP on a membrane were detected as visible spots with exposure time of 60 and 10 min, respectively, by using an instant photographic film and a camera luminometer. The proposed method was highly sensitive and was successfully applied to the detection of HRP conjugates as an alternative to the colorimetric method using a chromogenic substrate in a commercially available assay kit of Western blotting.

Blotting, Western↗

PubMedDate not supplied

Anatomic description of the free retroauricular flap.

Twenty-five human cadavers were examined to study the anatomy of the closed vascular system between the retroauricular artery and the retroauricular vein in the skin on the posterior aspect of the auricle and the mastoid process. The mean external diameters of the vessels supplying this region are 1.2 mm (artery) and 1.4 mm (vein). A flap averaging 5 x 7 cm may be taken from this area for use as facial cover.

Adult↗

PubMedDate not supplied

Thyroid hormone abnormalities in patients with diabetes mellitus.

Thyroid hormone abnormalities in serum were investigated in 47 patients with diabetes mellitus. Although no significant differences in T4 were found between normal subjects and diabetics, a group of diabetics whose fasting blood sugar levels were over 250 mg/dl showed significantly higher reverse T3 (rT3) (p less than 0.01) and lower T3 levels (p less than 0.05) than healthy controls. A significant correlation was observed between rT3 and FFA levels in diabetics. Moreover, patients in diabetic ketoacidosis showed markedly high rT3 with low T3 levels. With insulin treatment, these levels returned to normal in several days. These findings suggest that the reduction of T3 and the increase of rT3 may indicate an adaptation to limit catabolism in diabetics.

Adult↗

PubMedDate not supplied

Functional and morphometric study of cryopreserved human parathyroid tissue transplanted into nude mice.

As part of an ongoing study of the characteristics of transplanted fresh normal and pathologic parathyroid tissues, we transplanted cryopreserved human parathyroid tissue into nude mice. Hyperplastic glands cryopreserved for various lengths of time (<2 weeks and >1 year) were transplanted into the gluteus muscle of nude mice. Specimens grafted were of two sizes: 10 mg and 30 mg. Serum human parathyroid hormone (hPTH) concentration was estimated by a double-antibody immunoradiometric assay prior to transplantation and 2, 4, and 8 weeks after transplantation. A low-calcium diet was given to some mice to evaluate any effects on the grafts of low serum concentrations of calcium. All mice were killed 4 hours after injection of bromodeoxyuridine (Brd U) for assessment of the cell proliferation in grafted parathyroid tissue. Although hPTH secretion of cryopreserved tissue was only half that of fresh tissue, the cryopreserved tissue released hPTH, as did fresh tissue. hPTH secretion was accelerated by stimulation of a low-calcium diet, and PTH secretion was positively correlated with the volume of transplanted tissue. The number of Brd U-immunoreactive cells was correlated with the serum concentration of hPTH (r = 0.95), which indicates that cell proliferation is closely related to PTH secretion under the condition of successful transplantation. The experimental transplantation of cryopreserved tissue into nude mice, coupled with a concise immunohistochemical study of the grafts conducted prior to their transplantation into humans, can contribute to the evaluation of PTH secretion and cell proliferation.

Animals↗

PubMedDate not supplied

Hypocholesterolaemic effect of animal and plant fats in rats.

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Animals↗

PubMedDate not supplied

Severe endurance training fails to change myosin heavy-chain distribution of diaphragm.

Histochemical analysis by Green et al. (1989) revealed that severe endurance training caused a transformation from type IIA to type IIB fibres in the costal diaphragm region of the rat. With the use of the electrophoretic method, in the current study, it was re-examined whether such a change was brought about in this respiration muscle. The animals were capable of running for 240 min/day at 40 m/min during the final phase of a 16-week training program. Four heavy-chain (HC) isoforms were separated by a single percentage polyacrylamide gel electrophoresis of extracts from muscles. Densitometric analysis of these HC isoforms revealed that exercise training failed to change the relative distribution of any HC isoforms in the diaphragm.

Animals↗

PubMedDate not supplied

Phosphorylation of glutaminyl-tRNA synthetase and threonyl-tRNA synthetase by the gene products of dnaK and dnaJ in Escherichia coli K-12 cells.

In Escherichia coli K-12, the heat shock protein DnaK and DnaJ participate in phosphorylation of both glutaminyl-tRNA synthetase and threonyl-tRNA synthetase since when cellular proteins extracted from the dnaK7(Ts), dnaK756(Ts) and dnaJ259(Ts) mutant cells labeled with 32Pi at 42 degrees C were analyzed by two-dimensional gel electrophoresis, no phosphorylation of glutaminyl-tRNA synthetase and threonyl-tRNA synthetase was observed while phosphorylation of both aminoacyl-tRNA synthetases was detected in the samples extracted from wild-type cells.

Amino Acyl-tRNA Synthetases↗

PubMedDate not supplied

Benign convulsions with mild gastroenteritis: a report of 10 recent cases detailing clinical varieties.

To better define the characteristic clinical features of benign convulsions with mild gastroenteritis, recently recognized as a new entity in Japan, we reviewed all the 10 patients we have seen from 1992 to 1994. The clinical features have been previously reported in the literature to be afebrile generalized tonic-clonic seizures occurring between the first and the fifth sick day of mild gastroenteritis. In our series, four of 10 patients had convulsions before the onset of gastroenteritis. Overall, seizures were mostly brief and often repetitive occurring in cluster (19 seizures/10 episodes). Among these, a prolonged or partial seizure was frequently observed. In six of the 10 patients, the seizure type changed during an episode: from generalized to partial seizures (n = 2), from partial to generalized seizures (n = 2), or from partial to another type of partial seizures (n = 2). None in our series experienced a recurrence episode of afebrile convulsion during follow-up. These findings suggest that benign convulsions with mild gastroenteritis exhibit some variations in their clinical manifestation.

Child, Preschool↗

PubMedDate not supplied

Two cases of living-related intestinal transplantation.

We recently performed living-related small bowel transplant in two patients. The first patient was a 14-year-old boy with total parenteral nutrition (TPN)-dependent short-bowel syndrome associated with hypoganglionosis. He received a bowel graft from his 43-year-old mother. The second patient was a 27-year-old female who had undergone massive enterectomy due to volvulus. She underwent living-related bowel transplantation from her 57-year-old mother. In both cases, blood types were ABO identical, cytotoxic cross matches were negative, and cytomegalovirus status was positive to positive in both cases. Up to one third of the donor bowel was harvested from the distal ileum. The graft vessels were connected to infrarenal aorta and inferior vena cava. The immunosuppressive regimen consisted of daclizumab, tacrolimus, and steroids. The first patient developed progressive acute cellular rejection on postoperative day 9, requiring OKT-3 therapy. Two months after transplantation, he was weaned off TPN, tolerating oral intake with a fully functioning graft. The second patient was weaned off TPN on day 29 with a functioning graft. Her metabolic disorder dramatically improved. This patient developed indeterminate acute cellular rejection on day 111, which was successfully treated with bolus injections of steroid. Both donors had no complications; they were discharged on day 10. Living-related intestinal transplantation can be a treatment option for patients with short-bowel syndrome.

Adolescent↗

PubMedDate not supplied

CD80/86 and Th1 cytokine expression in intestinal graft following reperfusion and endotoxemia.

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Animals↗

PubMedDate not supplied

Positive and negative tropic curvature induced by microbeam irradiation of protonemal tip cells of the moss Ceratodon purpureus.

The photoreceptor phytochrome mediates tropic responses in protonemata of the moss Ceratodon purpureus. Under standard conditions the tip cells grow towards unilateral red light, or perpendicular to the electrical vector of polarized light. In this study the response of tip cells to partial irradiation of the apical region was analysed using a microbeam apparatus. The fluence response curve gave an unexpected pattern: whereas a 15-min microbeam with light intensities around 3 micro mol m (-2) s (-1) induced a growth curvature towards the irradiated side, higher light intensities around 100 micro mol m (-2) s (-1) caused a negative response, the cells grew away from the irradiated side. This avoidance response is explained by two effects: the light intensity is high enough to induce photoconversion into the active Pfr form of phytochrome, not only on the irradiated but also on the non-irradiated side by stray light. At the same time, the strong light on the irradiated side acts antagonistically to Pfr. As a result of this inhibition, the growth direction is moved to the light-avoiding side. Such a Pfr-independent mechanism might be important for the phototropic response to distinguish between the light-directed and light-avoiding side under unilateral light.

Bryopsida↗

PubMedDate not supplied

Development of an implantable artificial anal sphincter by the use of the shape memory alloy.

In this study, we developed and assessed an artificial anal sphincter driven by an shape memory alloy actuator (AS-SMA). The performance characteristics of the device were analyzed with a measurement system. Assessment showed that the AS-SMA could generate a pressure of 55 mm Hg at an atmospheric temperature of 36 degrees C, and displacement of the SMA actuator was 7.5 mm when the temperature of the SMA plate was 55 degrees C. To evaluate opening and closing, we studied a piglet colostomy model, in which the AS-SMA was implanted around the colostomy in the extraperitoneal space. Flow control tests using living porcine intestine revealed that the AS-SMA could maintain fecal continence against an intestinal pressure of 75 mm Hg. The high pressure zone corresponding to the location of the device was demonstrated in a manometric examination. For 6 days after surgery, we activated the AS-SMA twice a day and observed the bowel movements. The animal experiment indicated that the AS-SMA is able to control the bowel movements of patients with fecal incontinence if several problems, such as burning of tissue around the device and compression injury of the intestine, are resolved.

Alloys↗