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81.
HT Whelan LH Kras K Ozker D Bajic MH Schmidt Y Liu LA Trembath F Uzum GA Meyer AD Segura 《Canadian Metallurgical Quarterly》1994,22(1):7-13
BACKGROUND: This study was to evaluate the efficacy, safety and immunogenicity of recombinant human growth hormone (rhGH) in treatment of children with growth hormone deficiency (GHD). METHODS: We selected 15 children with GHD for a 12-month clinical trial and separated them into three groups with each 5 patients receiving one of the 3 tested rhGH (Saizen by Serono, Aubonne, Switzerland; Genotropin by KabiVitrum, Stockholm, Sweden and Humatrope by Eli Lilly, Indianapolis, USA). RESULTS: In Saizen group, 3 boys and 2 girls with a mean chronological age (CA) of 10.6 +/- 1.7 yrs and bone age (BA) of 6.7 +/- 1.2 yrs, at dose of 0.2 IU/kg sc tiw, gained an average BA of 2.1 +/- 1.3 yrs. The mean height velocity (HV) increased from 3.7 +/- 1.2 to 11.1 +/- 3.3 cm/yr. The height standard deviation score (SDS) increased from -4.2 +/- 3.1 to -3.1 +/- 2.9. In Genotropin group, 2 boys and 3 girls with a mean CA of 9.2 +/- 2.3 yrs and BA of 5.6 +/- 2.1 yrs, at dose of 0.1 IU/kg sc qd, gained an average BA of 0.8 +/- 0.2 yr. The mean HV increased from 3.4 +/- 0.7 to 11.3 +/- 2.0 cm/yr. The height SDS increased from -4.0 +/- 0.5 to -2.7 +/- 0.7. In Humatrope group, 4 boys and 1 girl with a mean CA of 10.3 +/- 3.5 yrs and BA of 5.8 +/- 2.9 yrs, at dose of 0.1 IU/kg sc qd, gained at average BA of 0.8 +/- 0.7 yr. The mean HV increased from 4.0 +/- 1.3 to 9.4 +/- 1.9 cm2yr, and the height SDS increased from -2.9 +/- 0.7 to -2.2 +/- 1.0. Very low titers of anti-rhGH antibodies were noted only in two patients, one in Saizen group (titer = 1:10) and the other in Genotropin group (titer = 1:6). Their HV was not affected (Saizen: 13.3 cm/yr, Genotropin: 11.2 cm/yr). One patient evolved subclinical hypothyroidism whereas no side effect at all was noted in the rest of patients. CONCLUSIONS: Three tested GH (Saizen, Genotropin, Humatrope) produced by recombinant DNA technology appear to make no significant difference in this clinical trial, and rhGH therapy is an effective and safe treatment for prepubertal GHD children. 相似文献
82.
83.
A Amano HT Sojar JY Lee A Sharma MJ Levine RJ Genco 《Canadian Metallurgical Quarterly》1994,62(8):3372-3380
Fimbriae are considered important in the adherence and colonization of Porphyromonas gingivalis in the oral cavity. It has been demonstrated that purified fimbriae bind to whole human saliva adsorbed to hydroxyapatite (HAP) beads, and the binding appears to be mediated by specific protein-protein interactions. Recently, we expressed the recombinant fimbrillin protein (r-Fim) of P. gingivalis corresponding to amino acid residues 10 to 337 of the native fimbrillin (A. Sharma, H.T. Sojar, J.-Y. Lee, and R.J. Genco, Infect. Immun. 61:3570-3573, 1993). We examined the ability of individual salivary components to promote the direct attachment of r-Fim to HAP beads. Purified r-Fim was radiolabeled with 125I and incubated with HAP beads which were coated with saliva or purified individual salivary components. Whole, parotid, and submandibular-sublingual salivas increased the binding of 125I-r-Fim to HAP beads. Submandibular-sublingual saliva was most effective in increasing the binding of 125I-r-Fim to HAP beads (1.8 times greater than that to uncoated HAP beads). The binding of 125I-r-Fim to HAP beads coated with acidic proline-rich protein 1 (PRP1) or statherin was four and two times greater, respectively, than that to uncoated HAP beads. PRP1 and statherin molecules were also found to bind 125I-r-Fim in an overlay assay. The binding of intact P. gingivalis cells to HAP beads coated with PRP1 or statherin was also enhanced, by 5.4 and 4.3 times, respectively, over that to uncoated HAP beads. The interactions of PRP1 and statherin with 125I-r-Fim were not inhibited by the addition of carbohydrates or amino acids. PRP1 and statherin in solution did not show inhibitory activity on 125I-r-Fim binding to HAP beads coated with PRP1 or statherin. These results suggest that P. gingivalis fimbriae bind strongly through protein-protein interactions to acidic proline-rich protein and statherin molecules which coat surfaces. 相似文献
84.
85.
The motorneuron degeneration (mnd) mutation causes one of the few late-onset progressive neurodegenerations in mice; therefore, the mnd mouse is a valuable paradigm for studying neurodegenerative biology. The mnd mutation may also model human neuronal ceroid lipofuscinosis (NCL) or Batten disease. mnd maps to the centromeric region of mouse chromosome 8, which likely corresponds to portions of human chromosomes 13,8, or 19; we note that the chromosome 13 portion maps close to a region thought to contain the human Type V NCL locus. We have identified candidate genes for the mnd locus from human chromosomes 13,8, and 19, and we are mapping these genes in the mouse to determine their proximity to the mutated locus and to refine the comparative human-mouse map in this area. A candidate gene from human chromosome 13 is LAMP1, which encodes lysosomal membrane protein 1. We found that LAMP1 in the mouse lies within the region of the mnd mutation. Therefore, we sequenced LAMP1 cDNAs from homozygous mnd mice and unrelated wildtype C57BL/6 mice. We find no differences between the two cDNA species in the regions examined, and expression analysis shows a similar LAMP1 protein distribution in wildtype and mutant mice, suggesting that an abnormal accumulation of material within normal lysosome structures is unlikely to be the pathogenetic mechanism in the mnd mouse. 相似文献
86.
V Cattell HT Cook H Ebrahim SN Waddington XQ Wei KJ Assmann FY Liew 《Canadian Metallurgical Quarterly》1998,53(4):932-936
To determine the relationship between quantitative Doppler parameters of portal, hepatic, and splanchnic circulation and hepatic venous pressure gradient (HVPG), variceal size, and Child-Pugh class in patients with alcoholic cirrhosis, we studied forty patients with proved alcoholic cirrhosis who underwent Doppler ultrasonography, hepatic vein catheterization, and esophagoscopy. The following Doppler parameters were recorded: time-averaged mean blood velocity, volume flow of the main portal vein flow, and resistance index (RI) of the hepatic and of the superior mesenteric artery. Doppler findings were compared with HVPG, presence and size of esophageal varices, and Child-Pugh class. There was a significant inverse correlation between portal velocity and HVPG (r = -.69), as well as between portal vein flow and HVPG (r = -.58). No correlation was found between RI in the hepatic artery or superior mesenteric artery and HVPG. No correlation was found between portal vein measurements and presence and size of varices. Severe liver failure was associated with lower portal velocity and flow. In patients with alcoholic cirrhosis, only portal vein blood velocity and flow, but neither hepatic nor mesenteric artery RI, are correlated to the severity of portal hypertension and to the severity of liver failure. 相似文献
87.
A Sharma HT Sojar DE Hruby HK Kuramitsu RJ Genco 《Canadian Metallurgical Quarterly》1997,238(2):313-316
The fimbriae of Porphyromonas gingivalis plays an important role in the pathogenesis of periodontal disease. A structural subunit of the P. gingivalis fimbriae, fimbrillin, has been shown to promote adherence of the bacteria to host surfaces and also induce an immune response. Biologically active domains of fimbrillin responsible for adherence or eliciting immune responses have been determined. In a previous study, we engineered the human oral commensal organism Streptococcus gordonii to express such biologically active domains on the surface of the bacteria as a vaccine delivery system. In this study we report an alternative approach of secreting fimbrillin polypeptide domains into the medium by modification of the surface-expression system described earlier. Such recombinant S. gordonii, in addition to being a source for antigen presentation to trigger a protective immune response, may have the added advantage of directly blocking the fimbriae-mediated adherence of P. gingivalis to the oral cavity following implantation. This approach can also be utilized for secreting other biologically important therapeutic molecules on mucosal surfaces for modulating local microenvironments. 相似文献
88.
Transport of 2-deoxy-D-galactose in Saccharomyces fragilis 总被引:2,自引:0,他引:2
2-Deoxy-D-galactose (dGal) transport in Saccharomyces fragilis is characterized by energy requirement and accumulation of the free sugar against a concentration gradient, indicating active transport. Besides free sugar dGal-1-phosphate, UDP-dGal and a trehalose-like derivative were found inside the cells. The accumulation of the phosphorylated derivatives was balanced by a concomitant decrease of ATP, orthophosphate and polyphosphates. With pulse labeling experiments it could be shown that the free sugar is transported into the cells. This conclusion was supported by several other experimental results, e.g. the lack of correlation between the sugar transport parameters and the dGal phosphorylation capacity, and the countertransport of free dGal evoked by galactose in the medium. The typical differences between this active transport mechanism and the transport-associated phosphorylation system, described previously, are discussed. 相似文献
89.
Symptoms of hereditary angioedema may present during the child's first years. Attacks may be a particular threat to the narrower airway of the child. An early diagnosis is most valuable because effective C1 inhibitor (C1 INH) concentrate is available. We present a reference area for the antigenic and functional determination of C1 INH by using uncontaminated umbilical cord blood from 80 normal newborns collected by puncturing vessels in the newly delivered placenta. We examined two full-term babies (1 and 2) from mothers with hereditary angioedema type I the same way. The concentration of C1 INH antigen was determined by radial immunodiffusion. The C1 INH functional assay was based on the addition of a known quantity of C1s, which enzymatically splits a chromogenic substrate. The test was performed in the presence of methylamine and heparin in a kinetic microtiter plate assay. Citrated plasma was used in both assays. The data obtained in the 80 cord blood samples (2.5-97.5 percentile) were 0.11-0.22 g/L for C1 INH antigen (adults, 0.15-0.33 g/L) and 47.2-85.9% for C1 INH function (percentage of adults). In cord blood, baby 1 had an antigenic value of 0.12 g/L (7.5 percentile) and C1 INH function of 61.8% (42 percentile). The corresponding values for baby 2 in cord blood were less than 0.05 g/L (0.106 g/L < 2.5 percentile) and 34.3% (12.9% < 2.5 percentile). Baby 2 had markedly lower C4 values yet much higher C4 activation products than baby 1. At 4 mo, baby 1 had an antigenic C1 INH value of 0.24 g/L.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
90.
HT Depypere M Dhont MR Verschraegen-Spae M Coppens 《Canadian Metallurgical Quarterly》1993,169(1):209-210
We report a tubal hydatidiform mole, most likely resulting from dispermic fertilization. Early hatching of the embryo, because of a defective zona pellucida, may have favored tubal implantation. 相似文献