551
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Ripamonti U, Magan A, Ma S, van den Heever B, Moehl T, Reddi AH. Xenogeneic osteogenin, a bone morphogenetic protein, and demineralized bone matrices, including human, induce bone differentiation in athymic rats and baboons. MATRIX (STUTTGART, GERMANY) 1991; 11:404-11. [PMID: 1787832 DOI: 10.1016/s0934-8832(11)80195-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Subcutaneous implantation of xenogeneic demineralized bone matrix does not initiate endochondral bone differentiation. Dissociative extraction in 4 M guanidine-HCl or 6 M urea has shown that the apparent species-specificity of intact bone matrix resides in its insoluble immunogenic component, since there is homology in solubilized osteogenic proteins amongst mammals. To further investigate the species-specificity and cross-species reactivity of bone matrix components, baboon and human demineralized bone matrix (DBM) and bovine osteogenin, purified greater than 50,000-fold and with an apparent molecular mass of 28-42 kilodaltons, were implanted in the subcutaneous space of athymic and euthymic rats and into the rectus abdominis of 16 baboons (Papio ursinus). Baboon DBM was also implanted in athymic and euthymic mice. Alkaline phosphatase activity and histology of implants harvested at day 11 and 30 showed that baboon and human DBM induced endochondral bone differentiation both in athymic rats and baboons. Bovine osteogenin in conjunction with baboon insoluble collagenous matrix induced extensive bone differentiation in athymic rats and baboons. Baboon and human DBM did not induce bone differentiation in euthymic rats and, in athymic mice, baboon DBM failed to induce bone differentiation, determining instead the recruitment of multinucleated giant cells. The results indicate that in rodents bone differentiation induced by intact bone matrix is species specific and that T-cell functions are not a requirement for bone induction, although immunologically competent rats block bone differentiation from xenogeneic matrix. Bone differentiation induced by human DBM in baboons suggests that intact bone matrices may not be species-specific amongst primates.(ABSTRACT TRUNCATED AT 250 WORDS)
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552
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Bowers G, Felton F, Middleton C, Glynn D, Sharp S, Mellonig J, Corio R, Emerson J, Park S, Suzuki J, Ma S, Romberg E, Reddi AH. Histologic comparison of regeneration in human intrabony defects when osteogenin is combined with demineralized freeze-dried bone allograft and with purified bovine collagen. J Periodontol 1991; 62:690-702. [PMID: 1753322 DOI: 10.1902/jop.1991.62.11.690] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A bone-inductive protein, osteogenin, has been isolated from long bones of humans and offers promise as a grafting material. Studies, however, suggest that osteogenin must be combined with a bone-derived matrix in order to initiate bone differentiation. The purpose of this study was to determine if osteogenin combined with demineralized freeze dried bone allograft (DFDBA), a bone-derived matrix, and with a bovine tendon-derived matrix will enhanced regeneration of intrabony defects in humans. The tendon-derived matrix and DFDBA used alone served as controls. The ability of each material to form a new attachment apparatus was evaluated independently in submerged and nonsubmerged environments in 2 patient populations. Lymphocyte testing was performed to assess development of an immune reaction to osteogenin. The most apical level of calculus on the root served as the histologic reference point to measure regeneration. Biopsies were obtained at 6 months and regeneration was measured histomorphometrically by 2 blinded evaluators. Serial sections from 36 submerged defects in 8 patients and 50 nonsubmerged defects in 6 patients were submitted for statistical analysis. Mean results indicate that osteogenin combined with DFDBA significantly enhanced regeneration of a new attachment apparatus and component tissues in a submerged environment. DFDBA plus osteogenin and DFDBA alone formed significantly more new attachment apparatus and component tissues than either the tendon-derived matrix plus osteogenin or the tendon-derived matrix alone in both submerged and nonsubmerged environments. There were no significant differences between the tendon-derived matrix plus osteogenin and the tendon-derived matrix alone in either the submerged or nonsubmerged environment. Osteogenin does not impair normal lymphocyte blastogenesis at 6 months postsurgical challenge.
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553
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Chen G, Shen Y, Zhang M, Zhu Z, Wang D, Liu X, Ma S. [Studies on warming the middle-jiao and analgesic effect of flos Caryophylli]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:429-32, 448 proceeding. [PMID: 1910510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of water extract and ether extract of Flos Caryophylli have been investigated by four experimental gastric ulcer models, choleresis in rats, two diarrhea models in mice, two pain stimulations in mice, and acute liver injury induced by CCl4 in rats. The results suggest that the action of Flos Caryophylli on dispelling the cold by warming the middle-jiao and curing abdominalgia is related to its anti-ulcer, choleresis increasing, anti-diarrhea and analgesic functions.
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554
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Ma S, Gross KC, Wasserman BP. Developmental Regulation of the (1,3)-beta-Glucan (Callose) Synthase from Tomato : Possible Role of Endogenous Phospholipases. PLANT PHYSIOLOGY 1991; 96:664-7. [PMID: 16668238 PMCID: PMC1080823 DOI: 10.1104/pp.96.2.664] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Activity levels of UDP-glucose: (1,3)-beta-glucan (callose) synthase in microsomal membranes of pericarp tissue from tomato fruit (Lycoperisicon esculentum Mill, cv Rutgers) were determined during development and ripening. Addition of the phospholipase inhibitors O-phosphorylcholine and glycerol-1-phosphate to homogenization buffers was necessary to preserve enzyme activity during homogenization and membrane isolation. Enzyme activity declined 90% from the immature green to the red ripe stage. The polypeptide composition of the membranes did not change significantly during ripening. The enzyme from immature fruit was inactivated by exogenously added phospholipases A(2), C, and D. These results suggest that the decline in callose synthase activity during ontogeny may be a secondary effect of endogenous lipase action.
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555
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Ma S, Yinn JH, Chen CF, Liu JM, Lin JT, Yeh FL, Tang YW, Wang CY, Fang RH. [Clinical application of Chinese forearm flap: 5-year review]. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1991; 47:45-9. [PMID: 1848462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Twenty-nine patients treated with the Chinese forearm flap from 1985 to 1989 were reviewed. This flap was used for soft tissue defect reconstruction in 19 cases, and phallus reconstruction in 10 patients. There were two cases of total flap failure and two cases of partial failure. Twenty cases used sensory flaps. Donor site complications included partial loss of the skin graft with tendon exposure in one patient (3.4%), limitation of range of movement of the wrist joint in one case (3.4%), and paresthesia over the radial site of the hand in 12 patients. On functional evaluation, 20 patients demonstrated no significant loss of strength in the donor extremity.
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556
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Huang CH, Yinn JH, Li WY, Ma S, Fang RH. Squamous cell carcinoma of the lip. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1990; 46:293-8. [PMID: 2178068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We reviewed 39 cases of squamous cell carcinoma of lip from 53 consecutive patients with carcinoma of the lip. The retrospective review includes age, location, risk factors, TNM classification, histologic differentiation, treatment methods, recurrent disease, site of recurrence, and follow-up status. Results reveal prognosis is related to original tumor size, local recurrence, and presence of cervical metastasis. Aggressive surgical treatment is recommended for identifiable poor prognostic lesions and includes surgical excision, prophylactic suprahyoid neck dissection, and possible radical neck dissection.
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557
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Ma S, Liang F, Wang S, Dong S, Yin S, Xue C, Lin Z. Treatment of 910 cases of atrophic gastritis with wei you decoction. J TRADIT CHIN MED 1990; 10:168-71. [PMID: 2277511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In treatment of 910 cases of chronic atrophic gastritis with Wei You Decoction, the overall effective rate was 96.9%. The disease was considered as due to deficiency of vital energy with stagnation of cold, and therefore treatment was to invigorate blood circulation. The Wei You Decoction had functions of replenishing vital energy, warming the middle burner, invigorating blood circulation, and resolving stasis, thus reversing the morbid process in the gastric mucosa. It was nontoxic, and the side-effects were minimal. The therapeutic effect was prompt and persistent. No malignant change was observed after taking the drug.
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558
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Sadasivan B, Ma S, Dujovny M, Ho LK, Ausman JI. Use of experimental aneurysms to evaluate wrapping materials. SURGICAL NEUROLOGY 1990; 34:3-7. [PMID: 2360161 DOI: 10.1016/0090-3019(90)90165-l] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Experimental venous pouch aneurysms in rats were wrapped with muscle, bovine collagen, muslin, cotton, or polyvinyl alcohol. The rats were killed 6 or 12 weeks later, and the aneurysms were compared with control aneurysms. Bovine collagen and muscle were reabsorbed and the aneurysms were similar to the control group. Cotton, muslin, and polyvinyl alcohol caused fibrosis around the aneurysm. However, giant aneurysms were found in the muslin and polyvinyl alcohol group. Cotton appears to be the most suitable material for wrapping aneurysms. The experimental venous pouch aneurysm model in rats can be used to evaluate wrapping materials.
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559
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Winslow RL, Ma S. Bifurcation analysis of nonlinear retinal horizontal cell models. II. Network properties. J Neurophysiol 1990; 64:248-61. [PMID: 2388069 DOI: 10.1152/jn.1990.64.1.248] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
1. We have previously presented a model of horizontal-cell soma isolated from fish retina. The model consists of a synaptic conductance representing input from photoreceptors in parallel with voltage-dependent membrane currents. Membrane-current models are based on I-V curves measured in isolated fish horizontal cells. Bifurcation theory was used to analyze model properties. The major findings of this study were 1) the inward Ca2+ current must be inactivated to account for horizontal-cell resting potentials and hyperpolarizing responses to light stimuli in a background of dark, and 2) the synaptic conductance controls the bifurcation structure of the model, with bistable behavior occurring at small and monostable behavior occurring at larger values of the synaptic conductance. The synaptic conductance at the point of transition from bistable to monostable behavior corresponds to the activation of as few as 100 synaptic channels. Thus tonic synaptic input from photoreceptors and inactivation of the inward Ca2+ current act to "linearize" responses of isolated horizontal-cell models. 2. The model described in this paper extends these analyses to large networks of horizontal cells in which each cell is coupled resistively to its nearest neighbors and is modeled with the use of the full complement of nonlinear membrane currents. Network responses to arbitrary patterns of conductance change (simulating inputs from photoreceptors), current-, or voltage-clamp stimuli are computed using the Newton iteration. The Newton descent direction is computed using either conjugate gradient (CG) or preconditioned CG algorithms. 3. An analysis of network stability properties is performed. Network I-V curves are computed by voltage-clamping the center node and computing the current required to maintain the clamp voltage. Computations are performed on networks of model cells in which the Ca2+ current is fully activated and the synaptic conductance is zero, thus making each cell as nonlinear as possible. Coupling conductance values slightly greater than 100 pS provide a current shunt sufficient to prevent the generation of Ca2+ action potentials in the network. This coupling conductance corresponds to the conductance of as few as two gap-junction channels and is more than two orders of magnitude less than the coupling known to exist between pairs of cultured horizontal cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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560
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Preston E, Ma S, Haas N. Ambient temperature modulation of fenfluramine-induced thermogenesis in the rat. Neuropharmacology 1990; 29:277-83. [PMID: 2325833 DOI: 10.1016/0028-3908(90)90013-h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The anti-obesity drug fenfluramine, promotes loss of weight by reducing food intake; however, there is controversy as to whether the drug can also elevate expenditure of energy. Resting consumption of oxygen (VO2) was measured in conscious rats to determine whether the injection of fenfluramine increased metabolic rate and whether prior fasting, or ambient temperature altered the response. Regardless of whether the rats were fed or had been fasted for 22 hr, in a thermoneutral environment (28 degrees C), the intraperitoneal injection of dl-fenfluramine (20 mg/kg) caused a raised oxygen consumption. This elevation was sustained to the end of the 60-min period of measurement after the injection, at which point the colonic temperature was found to be increased. This metabolic response to fenfluramine was largely attenuated when the drug was administered at 23 degrees C, and the colonic temperature of the rats was decreased by 60 min after the injection. At 4 degrees C, the injection of fenfluramine inhibited thermogenesis against cold, the oxygen consumption fell and the rats exhibited hypothermia. It was concluded that fenfluramine can increase the metabolic rate, but that this effect is not conditional on associated food intake, as has been reported. Rather, the ambient temperature governs whether stimulation or inhibition of thermogenesis will be evoked. These metabolic effects of fenfluramine explain, in part, its divergent effects on body temperature, reported previously.
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561
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Ma S, Kalousek DK, Zouves C, Yuen BH, Gomel V, Moon YS. The chromosomal complements of cleaved human embryos resulting from in vitro fertilization. JOURNAL OF IN VITRO FERTILIZATION AND EMBRYO TRANSFER : IVF 1990; 7:16-21. [PMID: 2338510 DOI: 10.1007/bf01133878] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Chromosome preparations were made from 25 cleaved abnormal human embryos at the two- to eight-cell stage after in vitro fertilization. Morphologically, these embryos showed either variable degrees of degeneration or an abnormal number of pronuclei before first cleavage. Among 14 successfully karyotyped embryos, only 3 had a normal chromosomal complement. Eleven showed chromosomal abnormalities, including triploidy, haploidy, and mosaicism. This finding documents a high incidence of chromosomal errors in morphologically abnormal early preimplantation embryos.
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562
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Abstract
Neodymium: YAG (Nd:YAG) transscleral cyclocoagulation successfully lowers intraocular pressure (IOP) over the short term in animals and humans. Twenty-eight eyes with uncontrolled glaucoma were prospectively followed over a mean period of 21.9 months. Mean pretreatment IOP was 47.5 mmHg. Mean posttreatment IOP was 19.9 mmHg (P less than 0.005). Mean (+/- standard deviation) number of treatments was 1.86 (+/- 1.11) Mean number of drugs used before and after treatment was 3.28 and 2.48, respectively (P less than 0.01). A total of 10.7% eyes went phthisical. Thirty percent of eyes with vision and good IOP control (i.e., less than 21 mmHg) lost some vision after the procedure. Neodymium:YAG transscleral cyclocoagulation appears to be an effective method of controlling IOP over the mid-term, but is associated with significant complications.
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563
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Ma S, Leu SY, Fang RH. Reconstruction of anorectal angle after abdominoperineal resection of rectum and anus--an animal model. Ann Plast Surg 1989; 23:519-22. [PMID: 2624395 DOI: 10.1097/00000637-198912000-00008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Voluntary control of the bowel movements is a social necessity. Lack of control relegates one to psychological debility and the possible need for a permanent colostomy. Anorectal angle plays an important role in fecal continence. In the normal individual, this angle lies in the range of 60 to 105 degrees. Perineal colostomy, once proposed for patients who had received abdominoperineal resection (APR), has been abandoned because of frank incontinence. This study used a canine model. The anorectal angle, external sphincter, internal sphincter, and the puborectalis were all destroyed after APR. The colon was pulled through the perineal defect. Enteropexy, gracilis muscle transfer, and perineal colostomy were performed to restore the anorectal angle. Barium enema was performed preoperatively and postoperatively. The anorectal angle was reconstructed within normal ranges after abdominoperineal resection of the rectum and anus.
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564
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Luyten FP, Cunningham NS, Ma S, Muthukumaran N, Hammonds RG, Nevins WB, Woods WI, Reddi AH. Purification and partial amino acid sequence of osteogenin, a protein initiating bone differentiation. J Biol Chem 1989; 264:13377-80. [PMID: 2547759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Osteogenin was purified from bovine bone matrix and its activity monitored by an in vivo bone induction assay. The purification method utilized extraction of the bone-inducing activity with 6 M urea, followed by chromatography on heparin-Sepharose, hydroxyapatite, and Sephacryl S-200. Active fractions were further purified by preparative sodium dodecyl sulfate gel electrophoresis without reduction. Osteogenin activity was localized in a zone between 30 and 40 kDa. The amino acid sequences of a number of tryptic peptides of the gel-eluted material were determined. Reduction and alkylation of purified osteogenin in 7 M guanidine hydrochloride resulted in the total loss of biological activity. Sodium dodecyl sulfate gel electrophoresis under reducing conditions revealed a broad band with an apparent molecular mass of 22 kDa.
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565
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Luyten FP, Cunningham NS, Ma S, Muthukumaran N, Hammonds RG, Nevins WB, Woods WI, Reddi AH. Purification and Partial Amino Acid Sequence of Osteogenin, a Protein Initiating Bone Differentiation. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)80003-5] [Citation(s) in RCA: 160] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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566
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Ma S, Kalousek DK, Zouves C, Yuen BH, Gomel V, Moon YS. Chromosome analysis of human oocytes failing to fertilize in vitro. Fertil Steril 1989; 51:992-7. [PMID: 2721734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
To assess the contribution of chromosome anomalies to the high failure of in vitro fertilization (IVF), 94 unfertilized eggs from 43 women participating in the IVF program were cytogenetically investigated. The mean age of the oocyte donors was 33.6 years. Chromosome karyotypes were obtained in 65 of 94 oocytes: 34 oocytes (52.3%) had a normal haploid chromosome complement; 10 (15.4%) were hypohaploid; 7 (10.8%) were hyperhaploid; 8 were diploid; and 6 were hypodiploid or hyperdiploid (from 36 to 53). Eleven eggs showed prematurely condensed chromosomes of the G1-phase from sperm, as well as a set of maternal metaphase II chromosomes. These results are compared to similar reports in the literature.
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567
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Ma S, Hill JO, Heng S. A thermal analysis study of the combustion characteristics of Victorian brown coals. ACTA ACUST UNITED AC 1989. [DOI: 10.1007/bf01911681] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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568
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Abstract
A randomized, prospective, double-blind study designed to compare the effectiveness of the use of cloxacillin with the result of nontreatment in patients undergoing surgical intervention of axillary hyperhidrosis was conducted from August 1987 to October 1987 at the Veterans General Hospital, Taipei, Taiwan. Forty-two patients were enrolled in this study. Fifty wounds (25 patients) were control subjects, and 34 wounds (17 patients) received cloxacillin. The positive bacterial culture rates of the tissues and draining from patients in the treatment group compared with the control group was statistically significantly lower (p less than 0.01). No significant differences presented in relation to age, sex, complication rate, fever index, and length of hospital stay. Prophylactic antibiotic is of no value in elective surgical intervention of axillary hyperhidrosis.
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569
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Reddi AH, Muthukumaran N, Ma S, Carrington JL, Luyten FP, Paralkar VM, Cunningham NS. Initiation of bone development by osteogenin and promotion by growth factors. Connect Tissue Res 1989; 20:303-12. [PMID: 2692957 DOI: 10.3109/03008208909023901] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The cellular and molecular basis of bone development and its regulation by differentiation and growth factors is an exciting area of current research. This article briefly reviews the historical progress in the isolation of osteogenin, a novel bone differentiation factor, and its modulation by well known growth factors. Endochondral bone development is a multistep sequential cascade and the process must be operationally dissected. It has been accomplished with the demineralized bone matrix-induced bone formation model. The reproducible development of cartilage and bone in an extraskeletal site permits the study of the initiation of the first cycle of endochondral bone formation and mineralization. Recent progress in the isolation of osteogenin, a specific bone differentiation factor, by heparin affinity chromatography permits the further investigation of the commitment and clonal expansion of the putative osteoprogenitor stem cells. Once initiated, bone formation is promoted by growth factors such as platelet derived growth factor, fibroblast growth factor, insulin like growth factor, transforming growth factor beta and a plethora of non specific cytokines. Finally bone development is further modulated by systemic hormones and nutrition and a host of physical signals including electrical, gravitational and mechanical forces.
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570
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Muthukumaran N, Ma S, Reddi AH. Dose-dependence of and threshold for optimal bone induction by collagenous bone matrix and osteogenin-enriched fraction. COLLAGEN AND RELATED RESEARCH 1988; 8:433-41. [PMID: 3224500 DOI: 10.1016/s0174-173x(88)80016-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Subcutaneous implantation of demineralized collagenous bone matrix results in local induction of new bone formation. The dose dependence of bone induction was investigated using different amounts of rat demineralized bone matrix (DBM) and also osteogenin-enriched fraction with and without inactive collagenous bone matrix (ICBM). There is a threshold for bone induction; at least 10 mg of DBM is required. There is a dose dependent increase in bone induction between 10 to 25 mg. Exogenous type I collagen was found to be stimulatory to bone induction when suboptimal doses of DBM are employed. The activity of osteogenin-enriched dissociative extract was enhanced by addition of ICBM. These results imply that optimal bone induction requires the combined action of soluble osteogenin-enriched fraction and insoluble collagenous substratum.
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571
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Nash JH, Ma S, Iyer VN. Characterization of Sym plasmids of Rhizobium leguminosarum strains able to nodulate Pisum sativum cv Afghanistan. PLANT MOLECULAR BIOLOGY 1988; 11:427-432. [PMID: 24272399 DOI: 10.1007/bf00039023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/1988] [Accepted: 06/29/1988] [Indexed: 06/02/2023]
Abstract
Rhizobium leguminosarum strains that can form nodules on Pisum sativum cv. Afghanistan have been reported as uncommon in Europe, North America and Africa [11, 12]. The organization of the nodulation regions of the symbiotic plasmids of five strains of R. leguminosarum originating from Denmark [9], which can nodulate P. sativum cv. Afghanistan, was compared with that of a Turkish strain (TOM [18]) by DNA hybridizations. Four of the five Danish strains were found to be very similar to the Turkish strain with respect to the overall organizations of their respective nodulation regions.
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572
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Wilson VL, Smith RA, Ma S, Cutler RG. Genomic 5-methyldeoxycytidine decreases with age. J Biol Chem 1987; 262:9948-51. [PMID: 3611071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Significant losses of DNA 5-methyldeoxycytidine residues in old age could disrupt cellular gene expression and contribute to the physiological decline of the animal. Thus, the 5-methyldeoxycytidine content of DNAs, isolated from the tissues of two rodent species of various ages, were determined. Mus musculus lost DNA methylation sites at a rate of about 4.7 X 10(4) (approximately 0.012% of the newborn level)/month. Peromyscus leucopus lost DNA 5-methyldeoxycytidine residues at a rate of only 2.3 X 10(4) (approximately 0.006% of the newborn level)/month. Since P. leucopus generally live twice as long as M. musculus, the rate of loss of DNA 5-methyldeoxycytidine residues appears to be inversely related to life span. Similar losses in genomic 5-methyldeoxycytidine content were also observed to correlate with donor age in cultured normal human bronchial epithelial cells.
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573
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Ma S, Zhang J. Patterns of population industrial structure and their alterations. POPULATION RESEARCH (PEKING, CHINA) 1986; 3:1-8, 17. [PMID: 12342175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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574
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Ma S. [Comparative analysis of the index of our population life quality]. REN KOU YAN JIU = RENKOU YANJIU 1986:31-3, 52. [PMID: 12280624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
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575
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Chen MJ, Chen DC, Ma S, Tang WS, Chen YF, Xie XL. [Antibiotic-associated colitis and Clostridium difficile]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1985; 7:316-8. [PMID: 2939996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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