Biomedical subjects

K Shi

Publications and source records attributed to K Shi.

At least 37 records · Page 2Linked to original sources

PubMed1999

The 3'-untranslated region polymorphism of the gene for skeletal muscle-specific glycogen-targeting subunit of protein phosphatase 1 in the type 2 diabetic Japanese population.

A newly identified 3'-untranslated region (UTR) polymorphism of the gene for skeletal muscle-specific glycogen-targeting subunit of protein phosphatase 1 (PPP1R3) was associated with insulin resistance and type 2 diabetes in Pima Indians (Xia J, Scherers W, Cohen PTW, Majer M, Xi T, Norman RA, Knowler WC, Bogardus C, Prochazka M: A common variant in PP1R3 associated with insulin resistance and type 2 diabetes. Diabetes 47:1519-1524, 1998). Thus, we investigated the frequency of polymorphism of the adenine- and thymine-rich element (ARE-1 and its variant ARE-2) in 426 Japanese type 2 diabetic and 380 nondiabetic subjects using a polymerase chain reaction (PCR)-restriction enzyme fragment length polymorphism (RFLP) method. The allele frequency of the ARE-2 variant in diabetic subjects was higher than that in nondiabetic subjects (0.34 vs. 0.29; P < 0.05), even though its frequency in Japanese subjects was lower (P < 0.001) than the reported value in Pima Indians (0.56). An aspartate polymorphism at codon 905 was 100% coupled to the ARE-2 allele, and its allele frequency was higher also in diabetic subjects. Although a serine substitution at codon 883 was partially linked with the ARE-2 allele, there was no difference between diabetic and nondiabetic subjects. These results indicate that the frequency of polymorphism of the PPP1R3 gene (ARE-2 and Asp905) is different between two ethnic groups and is increased in Japanese people with type 2 diabetes, suggesting that these variants may be a possible marker for searching for diabetogenic genes.

3' Untranslated Regions↗

PubMed1999

[Combined use of rhBMP2/BCB and free periosteum in repairing segmental defects in radii of rabbits].

OBJECTIVE: To study the efficacy of combined use of rhBMP2/BCBand free periosteal graft in repairing segmental bony defects. METHODS: A new grafting material (rhBMP2/BCB) was made by combining recombinant human BMP2 (rhBMP2) and an antigen-free bovine cancellous bone (BCB) as a carrier. rhBMP2/BCB was used alone in conjunction with free periosteal graft to repair a 1.5 cm defect in the radius of the rabbit. The defect-repairing capability for each of the treatment modalities was assessed radiographically, biomechanically, and by densitometry and histological studies. RESULTS: rhBMP2/BCB used alone was capable of healing the defect in large by 16 weeks, with a similar repair process and mechanism seen with RBX. Combined use of rhBMP2/BCB and free periosteal graft was superior in terms of increased amount and quality of the new bone formed at the early stage of the repair process (within 12 weeks) to rhBMP2/BCB used in isolation, with the defect basically healed by 12 weeks. CONCLUSIONS: Both methods are effective in repairing segmental bony defects, with rhBMP2/BCB used in conjunction with free periosteal graft being most preferred, considering the satisfactory osteogenesis, osteoconduction and osteoinduction.

Animals↗

PubMed1998

[Detection of human cytomegalovirus by PCR in patients with gastrointestinal disease].

Human cytomegalovirus (HCMV) genomes was detected by PCR in 51 patients' biopsy or operation specimens with gastrointestinal disease. The positive rate was 9.80%. At the same time, 41 patients' serum HCMV-IgM was detected by indirect immunofluorescence assay (IFA); the positive rate was 46.34%. Patients with cancer and colitis exhibited a higher HCMV infection rate than those without cancer and colitis. The results suggest that PCR is sensitive and specific in detection of gastrointestinal HCMV infection, and the examination of biopsy or surgical specimen is superior than that of IFA of serum HMCV-IgG.

Adult↗

PubMed1997

[The comparison of sensitivity of BGM cells, HeLa cells, HEL cells and A 549 cells to herpes simplex virus-1].

This study was undertaken to compare sensitivity of buffulo green monkey (BGM) cells, Hela cells, human embryo lung (HEL) cells and A549 cells to herpes simplex virus-1. The plague forming unit (PFU) technique was used to measure the four cell lines simultaneously. The results showed that BGM cells were superior to the Hela cells, HEL cells, A549 cells in terms of both sensitivity and rapidity of appearance of cytopathic effect (CPE). It indicates that BGM cells constitute a new, sensitive and valuable cell line used for the detection of HSV-1 in cell culture.

Animals↗

PubMed1997

[Influence of low energy He-Ne laser on spinal motor nerve cell].

The object of this experimental study was to investigate the influence of low-energy He-Ne laser on the motor nerve cells of the spinal cord. The experimental study included as follws: (1) Four rabbits were used in this experiment. The L5-6 spinal cord segment was irradiated by He-Ne laser percutaneously, the nerve velocity of the comon peroneal nerve was measured in order to determine the function of the spinal motor nerve cells when the peripheral nerve was intact. (2) The common peroneal nerve was transected on one side wothout repair, two weeks after laser irradiation, the grey mater of the spinal cord of L5-6 segment was procured for electronic microscopic examination. (3) The common peroneal nerve on the contralateral side was transected and followed by end-to-end anastomosis, and laser irradiation was done on the same spinal cord segment. Two weeks after irradiation, the nerve velocity of the common peroneal nerve and the toe expanding test were investigated. The results were: (1) the He-Ne laser can influence the spinal motor nerve cells function as expressed by latent rate when the peripherial nerve is intact. i.e. the nerve velocity is slower than mormal, and the amplitude is markedly decreared. (2) the change of the microstructure of the spinal motor nerve cells is comparatively slight in the 10 and 15 minutes groups. (3) the recovery of the nerve velocity and the toe expansion are more earlier in the 15 min. group. In short, the low-energy He-Ne laser can influence the function of the spinal motor nerve cells.

Animals↗

PubMed1997

[Influence of low energy He-Ne laser on regeneration of peripheral nerve].

The purpose of this experiment was to elucidate the influence of the low-energy He-Ne laser on the function of regeneration of peripheral nerve. Forty-four rabbits about 2.5 kg body weight were used in the experiment. The animals were divided into 4, 8, 12, 16 weeks groups according to the observation period. Six animals were used in each irradiated group and in the control group 5 rabbits were used in each observation period. Regeneration of the axon and myelinc sheath, the latent rate of the common peroneal nerve, the conditions of the anterior tibital muscle and the toe expansion test were all observed systematically in both groups. The experimental results was: A few thin regenerated axon was seen at 4 weeks in the irradiated group, while in the control group it might be seen at 8 weeks, the P value was < 0.01. A low amplitude latent rate of the common peroneal nerve is determined at the peroneal side of the anterior tibial muscle in a few animal at 4 weeks of the irradiated group, and it is not observed in the control group, from 12 to 16 weeks. THe latent rate of the common peroneal nerve was the irradiated group than in the controlled, the P value was < 0.01. The regeneration of the myeline sheath was evident in the irradiated group, and also the slstion of the musdle fibers anterior tibial muscle was clearly visible than the controlled. 16 weeks postoperatively, the toe expansion test was normal in the irradiated group, while in the control group it was the same as seen at 12 weeks after operation in the irradiated group. Now it was certain that the low-energy He-Ne laser could promole the function of the spinal motor nerve cells and accelerate the axonal regeneration.

Animals↗

PubMed1997

[Establishment of mutant strain from human lung cancer cell (A549) with characteristics of resistance to 8-AG and HGPRT deficiency].

A human lung cancer cell line (A549) mutant with hypoxanthine guanine phosphoribosyltransferase (HGPRT) deficiency and resistance to 8-AG was established by treatment of the A549 cells with 3 micrograms.ml-1 N-methyl-N'-nitro-nitrosoguanidine (MNNG), and prescreened in 0.25% agarose DMEM semisolid medium containing 20 micrograms.ml-1 8-AG. The mutant cells are resistant to cytotoxic effect of 8-AG and sensitive to hypoxanthine-aminopterin thymidine (HAT) selective medium. The mutant cells can be used as a candidate parental cells to fuse with the somatic cells.

Antimetabolites, Antineoplastic↗

PubMed1996

Exercise training has a long-lasting effect on prevention of non-insulin-dependent diabetes mellitus in Otsuka-Long-Evans-Tokushima Fatty rats.

Exercise training has been shown to be effective in preventing the development of non-insulin-dependent diabetes mellitus (NIDDM) in a model rat (Otsuka-Long-Evans-Tokushima Fatty [OLETF]). For determination of how long a preventive effect of exercise training against the development of NIDDM lasts in this model, six male OLETF rats each were assigned to training (1) for a whole experimental period, from 7 to 28 weeks of age (E-E); (2) for the first half of the period, from 7 to 15 weeks of age (E-S); and (3) for the second half of the period, from 16 to 28 weeks of age (S-E). In addition, eight male OLETF rats were given no exercise during the experimental period (S-S). At 28 weeks of age, E-E, E-S, S-E, and S-S rats, weighed averages of 514, 542, 557, and 669 g and had abdominal fat deposits of 13.9, 21.3, 38.2, and 76.0 g, respectively. At 28 weeks of age, the cumulative incidence of NIDDM in S-S was 100%, while none of the trained rats were diabetic. The glucose infusion rate (GIR) during a hyperinsulinemic euglycemic clamp test, an index of insulin sensitivity, in the E-E group was significantly greater than that in the S-S group. The values in the E-S and S-E groups were slightly, but not significantly, less than that in the E-E group. Morphologic studies on the pancreas of E-E rats and S-E rats showed minimal changes of islets, whereas sections of islets from E-S rats appeared slightly enlarged and fibrotic, although significantly less than those of islets of S-S rats. These results demonstrate that the preventive effect of excercise training against the development of NIDDM lasts for at least 3 months after the cessation of exercise in this model.

Animals↗

PubMed1996

Detection of serum immunoglobulin M to human cytomegalovirus by western blotting correlates better with virological data than detection by conventional enzyme immunoassay.

Western blotting (immunoblotting) with proteins separated from purified human cytomegalovirus (HCMV) particles (viral WB) has repeatedly been shown to be a reliable and sensitive method for detecting HCMV-specific immunoglobulin M (IgM). The aim of the present work was to determine whether IgM detected by viral WB correlates with virological diagnosis better than conventional enzyme immunoassay (conv-EIA). The presence of an active HCMV infection was documented on the basis of isolation of virus from urine and/or saliva and on the basis of antigenemia and/or PCR with polymorphonuclear leukocytes for immunocompetent and immunocompromised subjects, respectively. The agreement observed between IgM detected by viral WB and the results obtained by virological detection of HCMV was significantly higher (88.7%) than the agreement of IgM detected by conv-EIA and virological results (67.5%).

Antibodies, Viral↗

PubMed1994

Sexual difference in the incidence of diabetes mellitus in Otsuka-Long-Evans-Tokushima-Fatty rats: effects of castration and sex hormone replacement on its incidence.

The incidence of non-insulin-dependent diabetes mellitus in a model rat (Otsuka-Long-Evans-Tokushima Fatty [OLETF]) has been shown to be much higher in males than in females. To evaluate the role of sex hormones in the development of diabetes in this model, we performed biochemical and morphological studies on the effects of castration and sex hormones on the development of non-insulin-dependent diabetes mellitus in these rats. The rats were randomly assigned to six groups of 10 rats each, three groups of males and three of females. Two of the male groups and two of the female groups were castrated at 5 weeks of age, and the third male and female groups received sham operations. From 9 to 30 weeks of age, one group of castrated males received testosterone enanthate (1 mg-wk-1) and one group of castrated females received estradiol valerate (1 mg.wk-1). The other castrated groups received an equal volume of vehicle only. At 30 weeks of age, the cumulative incidences of diabetes mellitus in the sham-operated male and female rats were 100% and 0%, respectively. Orchiectomy reduced the incidence of diabetes to 20%, whereas ovariectomy increased it to 30%. Administration of sex hormones restored the incidence to 89% in males and 0% in females. In vivo insulin-stimulated glucose uptake as measured with a euglycemic clamp was reduced in sham-operated males, castrated males with hormone replacement (HR), and castrated females without HR as compared with sham-operated females and castrated females with HR.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Effects of difference in amount of exercise training on prevention of diabetes mellitus in the Otsuka-Long-Evans-Tokushima fatty rats, a model of spontaneous non-insulin-dependent diabetes mellitus.

Exercise training every day has been shown to be effective in preventing the development of non-insulin-dependent diabetes mellitus (NIDDM) in a model rat (Otsuka Long Evans Tokushima Fatty (OLETF)). For determination of whether less vigorous exercise training also has a protective effect against the development of NIDDM in this model, seven male OLETF rats each were assigned to training every other day, every 3 days and every 7 days from 6 to 30 weeks of age. At 30 weeks of age, rats trained every other day, 3 days, 7 days and sedentary rats weighed averages of 547, 548, 603 and 695 g and had abdominal fat deposits of 28, 24, 32 and 72 g, respectively. The mean meterages of running of rats trained every other day, 3 days and 7 days over the whole experimental period were 9630, 5166 and 1685 m/week, respectively. At 30 weeks of age, the cumulative incidence of NIDDM in sedentary rats was 85.7% (6/7), while none of the trained rats became diabetic except for one of rats trained every 7 days. The glucose infusion rate (GIR), an index of insulin sensitivity, in the group trained every 7 days, 60.6 +/- 5.0 mumol.kg-1.min-1, was significantly greater than that in the sedentary group, 21.7 +/- 1.7 mumol.kg-1.min-1. Morphological studies on the pancreas of rats trained every other day and every 3 days showed minimal changes of islets, whereas sections of islets from rats trained every 7 days appeared enlarged and fibrotic, though significantly less so than the islets of sedentary rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Protein crystallization in space.

The microgravity environment of space is an ideal place to study the complicated protein crystallization process and to grow good-quality protein crystals. A series of crystal growth experiments of 10 different proteins was carried out in space on a Chinese re-entry satellite FSW-2 in August, 1992. The experiments were performed for about two weeks at a temperature of 18.5 +/- 0.5 degrees C using a tube-like crystallization apparatus made in the Shanghai Institute of Technical Physics, Academia Sinica. More than half of 48 samples from 6 proteins produced crystals, and the effects of microgravity on protein crystal growth were observed, especially for hen-egg white lysozyme and an acidic phospholipase A2 from the venom of Agkistrodon halys Pallas. Analyses of the crystallization of these two enzymes in this mission showed that the microgravity environment in space may be beneficial to improve size, external perfection, morphology, internal order, and nucleation of protein crystals. Some of these positive microgravity effects were also demonstrated by the growth of protein crystals in gelled solution with the above two enzymes. A structural analysis of the tetragonal lysozyme crystal grown in space is in progress.

Ancrod↗

PubMed1994

Protein crystal growth in microgravity.

Protein crystal growth is quite important for the determination of protein structures which are essential to the understanding of life at molecular level as well as to the development of molecular biotechnology. The microgravity environment of space is an ideal place to study the complicated protein crystallization and to grow good-quality protein crystals. A number of crystal-growth experiments of 10 different proteins were carried out in August, 1992 on the Chinese re-entry satellite FSW-2 in space using a tube crystallization equipment made in China. A total of 25 samples from 6 proteins produced crystals, and the effects of microgravity on protein crystal growth were observed, especially for an acidic phospholipase A2 and henegg-white lysozyme which gave better crystals in space than earth-grown crystals in ground control experiments. The results have shown that the microgravity in space favors the improvement of the size, perfection, morphology and internal order of the grown protein crystals.

Crystallization↗

PubMed1994

The effect of probucol on the development of non-insulin dependent diabetes mellitus in Otsuka Long Evans Tokushima Fatty (OLETF) rats.

The effect of probucol which acts as a scavenger of free radicals, on preventing the development of non-insulin dependent diabetes mellitus (NIDDM) in a model rat (Otsuka Long Evans Tokushima Fatty [OLETF]) was examined. Sixteen male OLETF rats aged 5 weeks were divided into two groups. One group were fed standard laboratory chow and the other group were fed the chow containing 1% probucol. At 12, 16, 24 weeks of age, an oral glucose tolerance test (OGTT) was performed. At 24 weeks of age, the cumulative incidences of diabetes mellitus in both groups were 100%. After two weeks, insulin-mediated glucose uptake was measured using a euglycemic clamp technique. There was no significant difference in glucose infusion rates between both groups. At the end of the experiment, plasma lipid concentrations were measured. The serum total cholesterol levels were significantly lower in rats fed probucol containing chow (66.3 +/- 3.7 mg/dl) than those of rats fed standard laboratory chow (78 +/- 6.4 mg/dl). On the other hand, the serum triglyceride level were not significantly different between them. Histological studies on the pancreas of both groups showed enlarged fibrotic islets and mononuclear cell infiltration in the periinsular area, though to a modest extent. These results demonstrated that probucol was not effective in preventing the development of NIDDM in this model animal. Considering these data, inflammatory destruction of pancreatic beta cells by free radical may not be involved in the development of NIDDM.

Animals↗

PubMed1993

Is exercise training effective in preventing diabetes mellitus in the Otsuka-Long-Evans-Tokushima fatty rat, a model of spontaneous non-insulin-dependent diabetes mellitus?

We determined whether exercise training is effective in preventing the development of diabetes mellitus in a model rat (Otsuka-Long-Evans-Tokushima Fatty [OLETF]) with non-insulin-dependent diabetes mellitus (NIDDM). Thirty male OLETF rats aged 5 weeks were assigned to one of the following three groups: trained rats placed individually in an exercise wheel (EW) cage, EW-control rats housed in the same cages equipped with a fixed rotatory wheel, and sedentary rats maintained two or three to a conventional cage. Eight male diabetes-resistant Long-Evans rats were used as nondiabetic controls. At 24 weeks of age, the trained, EW-control, sedentary, and nondiabetic control rats weighed an average of 445, 559, 621 and 513 g and had abdominal fat deposits of 16, 55, 67, and 23 g, respectively. The mean amount of exercise of trained rats was 5,243 m/d. At 24 weeks of age, the cumulative incidences of diabetes mellitus in sedentary and EW-control rats were 78% and 50%, respectively, while neither trained nor nondiabetic control rats became diabetic. Fasting and 120-minute plasma immunoreactive insulin (IRI) levels after oral glucose administration were significantly lower in the trained group than in the other groups. In vivo insulin-stimulated glucose uptake as measured with a euglycemic clamp was reduced 37% in sedentary rats and increased 35% in trained rats compared with that in nondiabetic control rats. Morphological studies on the pancreas of sedentary and EW-control rats showed enlarged multilobulated fibrotic islets, whereas sections of islets from trained rats appeared normal but slightly enlarged.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗

PubMed1993

Cyclophosphamide-induced diabetes in Long-Evans Tokushima Lean rats: influence of ovariectomy on the development of diabetes.

We studied the effect of treatment with cyclophosphamide (CY) on the incidence of diabetes in Long-Evans Tokushima Lean (LETL) rats, a newly established strain of spontaneously type I diabetic rats. The overall incidence of diabetes among 356 LETL rats treated with CY was 25.6%, which was significantly higher than the 10.5% among 857 untreated LETL rats at 27 weeks of age, and there was no significant sex difference. The incidence of CY-induced diabetes in adult (> 16 weeks of age) female LETL rats was 7.7% (10/130), which was significantly lower than that in other CY-treated groups of LETL rats. No diabetes mellitus was induced by administration of CY to 23 diabetes-resistant LETO rats. There were no significant differences in the degrees of hyperglycemia or hyperketonemia in spontaneously and CY-induced diabetic LETL rats, but the plasma glycated albumin level of CY-induced diabetic rats (10.3% +/- 2.1%) was significantly higher than that of spontaneously diabetic rats (8.2% +/- 1.3%), suggesting that plasma glucose levels increased more rapidly in the latter. More than half of the diabetic rats showed type C or D morphological changes of the islets, ie, atrophic change with little mononuclear cell infiltration or almost complete loss of the islets. However, distributions of various types of morphological changes in the islets were not significantly different in the two groups. Ovariectomy (OVX) significantly increased the incidence of CY-induced diabetes in adult female rats from 7.7% to 20.8%. The number of CD8+ cells was significantly increased in noncastrated adult female LETL rats and decreased to the level of other groups after OVX.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Plasma glucagon responses to insulin-induced hypoglycemia and arginine in spontaneous non-insulin-dependent diabetes mellitus (NIDDM) rats, Otsuka Long Evans Tokushima Fatty (OLETF) strain.

Pancreatic A-cell function in the newly developed Otsuka Long Evans Tokushima Fatty (OLETF) strain of non-insulin-dependent diabetes mellitus (NIDDM) rats was examined in relation to the morphological changes in their islets and the plasma glucagon responses to insulin-induced hypoglycemia and an arginine test by chronological studies in seven male OLETF and seven male non-diabetic control Long Evans Tokushima Otsuka (LETO) rats each at 10, 16 and 24 weeks of age and eight male OLETF rats that were placed in a cage with a wheel for exercising from 5 to 24 weeks of age. The hormonal contents and morphological features of the pancreas of these rats were examined. After iv injection of insulin, the plasma glucagon level rose significantly from the basal level in OLETF rats at 10 weeks old, but little if at all in those of 16 and 24 weeks old. The pancreatic A cells of LETO rats of all age groups responded equally well to glucopenia. The areas under the response curves of plasma glucagon (sigma delta IRG) during the 90 min of insulin-induced hypoglycemia were 14496 +/- 7860 vs 9588 +/- 3930, 2257 +/- 3018 vs 9235 +/- 5447 (p < 0.05) and 826 +/- 985 vs 9707 +/- 2510 (p < 0.01) ng.min-1.l-1 in OLETF rats vs LETO rats of 10, 16 and 24 weeks old, respectively. The plasma glucagon responses during the arginine test were higher in OLETF rats than in LETO rats at 10 and 16 weeks but not at 24 weeks of age.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Management of major arterial injuries of the limbs in 166 cases.

The charts of 166 patients with major arterial injuries (175 arterial repairs) inflicted during periods of peace and war time were reviewed. One hundred and sixty-seven (95%) of the arteries repaired remained patent. Nine patients had limbs which developed ischemic contracture. Nine patients required amputations. Follow-up data was obtained from seventy-five patients with an average follow-up of five years and one month (six months to thirty years). Early diagnosis, prompt treatment including fasciotomies when indicated, complete debridement, appropriate coverage, meticulous surgical technique, and simultaneous treatment of concomitant injuries are all crucial factors in successful limb salvage. Major arterial injuries of the limb occur frequently in our patient population, especially in time of war. Successful treatment of major arterial injuries may be life-saving, as well as allowing limb salvage and restoration of limb function. The purpose of this study is to review our experience with repair of major arterial injuries.

Adolescent↗