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91.
FP Vandenbussche GE Griever D Oepkes MC Postuma S Le Cessie MJ Keirse 《Canadian Metallurgical Quarterly》1997,25(4):340-346
OBJECTIVE: This study examined the effect of incarceration during pregnancy on infant birth weight. METHODS: North Carolina prison records were matched to North Carolina birth certificates and health services records to identify 94 women who were incarcerated during one pregnancy but not incarcerated during another pregnancy. Paired analyses examined differences between the pregnancies in terms of the women's characteristics and use of health services. A generalized estimating equations analysis modeled infant birth weight as a function of the number of days that a woman was incarcerated during pregnancy, accounting for the correlation between the birth weights of two infants born to the same mother and several potentially confounding variables. RESULTS: Since the women were significantly more likely to have been incarcerated during the second of the pair of pregnancies, as a group they were significantly older and had more children at the time of the incarcerated pregnancy than at the time of the home pregnancy. After controlling for important covariates, a higher number of pregnancy days spent incarcerated was found to be associated with higher infant birth weight. CONCLUSION: These findings suggest that aspects of the prison environment such as shelter and regular meals may enhance pregnancy outcomes among very high risk women. Health professionals should join others in efforts to assure that health-promoting resources such as adequate shelter, nutritional support, and substance abuse treatment programs are available to all pregnant women. 相似文献
92.
A study on how to apply PCR as a diagnostic test for the infants born to HIV-1 infected mothers is described. All steps including clinical care, blood sampling, specimen processing and PCR analysis were carried out using native facilities and personnel. An open cohort of 130 children was evaluated at birth, 1, 6, 9, 15, and 18 months of age. Definite infection status was assessed by clinical and serological data during an 18 months of follow up period. PCR results were reported as positive or negative when at least 2 concordant data were denoted. This in-house PCR, compared to known infection status, gave 100% sensitivity and 94.4% specificity within 6 months after birth. On the other hand, clinical diagnosis could identify only the infected infants at 9 months of age. The HIV-1 transmission rate from mother to infant was 23.2%. Though this PCR was not at an optimal level of specificity, it was still beneficial to identify uninfected infants in the first year of their lives and avoid unnecessary medical care. Here, we report an in-house PCR that offers good performance at low cost for the diagnosis of HIV-1 vertical transmission. 相似文献
93.
J Nordahl S Mengarelli-Widholm K Hultenby FP Reinholt 《Canadian Metallurgical Quarterly》1995,57(6):442-449
Fibronectin is a well known glycoprotein of extracellular connective tissue matrices due to a specific amino acid-sequence (RGD) suggested to act as an attachment factor in cell-cell or cell-matrix interactions. Although also present in bone, little is known about the role of fibronectin in this tissue. To obtain data for discussions on function we used ultrastructural immunolocalization techniques to quantitatively examine the distribution of fibronectin in various bone matrix compartments. The study was focused on three different stages of endochondral ossification in growing long bones of young rats. The results show large amounts of fibronectin in mature bone tissue. At a higher magnification, an obvious fibronectin association to individual fibrils of collagen type I was demonstrated. Intracellular labeling was observed in Golgi-related vesicles in some active osteoblasts of metaphyseal bone, indicating local synthesis of fibronectin. In contrast to previous suggestions based on light microscopic observations, the labeling of bone or cartilage matrices facing the surface of all cell types were low. The pattern is clearly different from that of osteopontin and bone sialoprotein, two other bone matrix proteins with the same cell-binding sequence. Our results indicate that fibronectin at these stages of development participates in matrix organization rather than being an important link between cartilage or bone matrix and adjacent cells. 相似文献
94.
We describe a 65-year-old woman with eosinophilic pneumonitis induced by sulphasalazine. Laboratory findings revealed peripheral eosinophilia. The chest X-ray showed bilateral infiltrations, which disappeared after sulphasalazine was discontinued. 相似文献
95.
C Napoli FP D'Armiento FP Mancini A Postiglione JL Witztum G Palumbo W Palinski 《Canadian Metallurgical Quarterly》1997,100(11):2680-2690
To determine whether oxidized LDL enhances atherogenesis by promoting monocyte recruitment into the vascular intima, we investigated whether LDL accumulation and oxidation precede intimal accumulation of monocytes in human fetal aortas (from spontaneous abortions and premature newborns who died within 12 h; fetal age 6.2+/-1.3 mo). For this purpose, a systematic assessment of fatty streak formation was carried out in fetal aortas from normocholesterolemic mothers (n = 22), hypercholesterolemic mothers (n = 33), and mothers who were hypercholesterolemic only during pregnancy (n = 27). Fetal plasma cholesterol levels showed a strong inverse correlation with fetal age (R = -0.88, P < 0.0001). In fetuses younger than 6 mo, fetal plasma cholesterol levels correlated with maternal ones (R = 0.86, P = 0.001), whereas in older fetuses no such correlation existed. Fetal aortas from hypercholesterolemic mothers and mothers with temporary hypercholesterolemia contained significantly more and larger lesions (758,651+/-87,449 and 451,255+/-37,448 micron2 per section, respectively; mean+/-SD) than aortas from normocholesterolemic mothers (61,862+/-9,555 micron2; P < 0.00005). Serial sections of the arch, thoracic, and abdominal aortas were immunostained for recognized markers of atherosclerosis: macrophages, apo B, and two different oxidation-specific epitopes (malondialdehyde- and 4-hydroxynonenal-lysine). Of the atherogenic sites that showed positive immunostaining for at least one of these markers, 58.6% were established lesions containing both macrophage/foam cells and oxidized LDL (OxLDL). 17.3% of all sites contained only native LDL, and 13.3% contained only OxLDL without monocyte/ macrophages. In contrast, only 4.3% of sites contained isolated monocytes in the absence of native or oxidized LDL. In addition, 6.3% of sites contained LDL and macrophages but few oxidation-specific epitopes. These results demonstrate that LDL oxidation and formation of fatty streaks occurs already during fetal development, and that both phenomena are greatly enhanced by maternal hypercholesterolemia. The fact that in very early lesions LDL and OxLDL are frequently found in the absence of monocyte/macrophages, whereas the opposite is rare, suggests that intimal LDL accumulation and oxidation contributes to monocyte recruitment in vivo. 相似文献
96.
FP Guengerich NA Hosea A Parikh LC Bell-Parikh WW Johnson EM Gillam T Shimada 《Canadian Metallurgical Quarterly》1998,26(12):1175-1178
Today cytochrome P450 (P450) research is accepted as an integral part of drug development and discovery. Work leading to this point included biochemical studies on P450 in experimental animal models and application to human systems. The development of recombinant expression systems has been an important part of the progress, and in this article we describe some recently developed bacterial systems that can be used for the production of metabolites, genotoxicity testing, and screening in random mutagenesis work. Rate-limiting aspects of P450 reactions vary with particular systems, and further investigations are in order. Non-ionic detergents have been utilized widely in P450 purification work; these compounds are now shown to be substrates for P450s. These oxidations are not only of fundamental interest in expanding the repertoire of P450 substrates but have significance in light of human exposure to these compounds. 相似文献
97.
AE Rudenko FP Trinus LV Korzhenevski? TA Bukhtiarova AZ Koval' VD Maly? OV Novikova EV Tkachenko 《Canadian Metallurgical Quarterly》1996,(5-6):134-136
The authors submit results of treatment of patients having suffered from postherpetic pain syndrome (herpetic ganglionitis of the cervical, thoracic, lumbosacral localization, postherpetic intercostal neuralgia, ganglionitis of the trigeminal nerve). In viral diseases, amizone has marked analgetic, antiinflammatory, and immunomodulating effects. The drug is well tolerated by patients, is not associated with side effects under prescribed doses (0.25-0.75 as one dose on a three- or four-times daily schedule during the course of treatment lasting three or four weeks). The drug preparation in question is less effective in the treatment of chronic recurring post-therapeutic intercostal neuralgias, radiculalgia. 相似文献
98.
K Eckols FP Bymaster CH Mitch HE Shannon JS Ward NW DeLapp 《Canadian Metallurgical Quarterly》1995,57(12):1183-1190
The functionally selective M1 agonist xanomeline, which is currently undergoing clinical trials as a therapy for Alzheimer's disease, was compared to the muscarinic agonist carbachol for effects on secretion of soluble amyloid precursor protein (APPs) from Chinese hamster ovary cells transfected with the human m1 receptor (CHO-m1). Release of APPs from CHO-m1 cells was increased maximally (4-10 fold) by 100 microM carbachol (EC50 = 11 microM) and by 100 nM xanomeline (EC50 = 10 nM). Stimulation of APPs secretion by xanomeline and carbachol was blocked by preincubation with 1 microM atropine. Carbachol did not stimulate APPs secretion from non-transfected CHO cells. Pilocarpine at 1 mM also increased APPs release. The efficacy of carbachol, xanomeline and pilocarpine for stimulating APPs secretion did not differ significantly. Activation of protein kinase C (PKC) in m1 transfected cell lines by 1 microM phorbol dibutyrate (PDBu) increased APPs release, and this was inhibited 97% by the PKC inhibitor bisindolemalemide. The PKC inhibitor decreased xanomeline and carbachol-stimulated APPs secretion by only 25-30%. These results demonstrate that xanomeline increased APPs release by activation of m1 muscarinic receptors and support the possibility that cholinergic replacement therapy for Alzheimer's Disease may reduce amyloid deposition. 相似文献
99.
100.
1,N2-Ethenoguanine (1,N2-epsilon-Gua) and 5,6,7,9-tetrahydro-7-hydroxy-9-oxoimidazo[1,2-a]purine (HO-ethanoGua) are two modified bases formed in the reaction of DNA with 2-chlorooxirane, the epoxide derivative of vinyl chloride. The oligonucleotides (19-mers), 5'-CAGTGGGTG*TCCGAATTGA-3', were prepared, with each of these modified bases substituted for G at G*. HO-ethanodeoxyguanosine exists predominantly as a mixture of diastereomers of the closed cyclic hemiaminal form, 5,6,7,9-tetrahydro-7-hydroxy-9-oxoimidazo[1,2-a]purine, shown by H2(18)O experiments to be in equilibrium with the open form, N2-(2-oxoethyl)Gua. Both adducts retarded the 3'-extension of a complementary 10-mer primer by all of the polymerases examined, but in every case, some full-length product was obtained. Nucleotide sequence analysis indicated misincorporation of dGTP and dATP across from both 1,N2-epsilon-Gua and HO-ethanoGua, with the extent varying considerably among the polymerases. Similar results were obtained when the abilities of the polymerases to incorporate a single dNTP were evaluated. In addition, -1 and -2 base frame shifts were detected with both 1,N2-epsilon-Gua and HO-ethanoGua with some of the polymerases. Steady-state kinetic experiments with Escherichia coli polymerase I exo- and T7 polymerase exo-/thioredoxin showed large decreases in k(cat) for all dNTP incorporations compared to the normal G x dCTP pair and high misincorporation frequencies for dATP and dGTP with both adducts (compared to dCTP). Collectively, the results indicate that both of these adducts have considerable miscoding potential with some of these polymerases, that there are a number of differences between the 1,N2-epsilon-Gua and HO-ethanoGua adducts (which formally differ only in the presence of the elements of water), and that misincorporation of dNTPs at a single modified base can vary considerably among different polymerases even in the absence of exonuclease activity. 相似文献