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Fetal and maternal lipoprotein metabolism in human pregnancy complicated by type I diabetes mellitus
Serum lipid, apolipoprotein concentration, and lipoprotein composition were determined in maternal and umbilical venous cord blood at delivery by elective Cesarean section (CS) in 10 singleton, full-term pregnancies with maternal insulin-dependent diabetes mellitus (type I DM), which predated pregnancy, and in 22 nondiabetic pregnancies. The objectives of the study were to determine the influence of maternal type I DM, and hence potential fetal overnutrition on fetal lipid metabolism. There were no significant differences in gestational age, fetal weight, or fetal serum insulin concentration between the type I DM group and those with nondiabetic pregnancies, although fetal venous cord blood glucose was 3.4 mmol/L (3.0-4.5 mmol/L) (median and 25th-75th percentiles) and 2.9 mmol/L (2.0-3.4 mmol/L), respectively, and maternal Hemoglobin A1c [9.6% (8.2-10.7%) and 6.8% (6.3-7.8%), respectively], was significantly greater in the type I DM subjects (P < 0.02 and 0.002 respectively). Plasma nonesterified fatty acid (NEFA) concentrations were lower in the type I DM mothers [0.85 mmol/L (0.56-2.31 mmol/L) compared with 1.14 mmol/L (0.88-1.24 mmol/L] in nondiabetic pregnancies; P < 0.0001). Serum high-density lipoprotein phospholipids (HDL-PL) were increased in type I DM mothers because of elevated HDL2 phospholipid [0.39 mmol/L (0.27-0.48 mmol/L) compared with 0.12 mmol/L (0.06-0.21 mmol/L), respectively, P < 0.01). The maternal HDL cholesterol (C) concentration was not significantly different in the uncomplicated and type I DM pregnancies. However, in the umbilical venous cord blood, serum levels of NEFA [0.49 mmol/L (0.33-1.29 mmol/L) in type I DM compared with 0.13 mmol/L (0.06-0.33 mmol/L) in nondiabetics; P < 0.02)], total cholesterol (TC) [2.87 mmol/L (1.65-4.86 mmol/L) in type I DM compared with 1.65 mmol/L (1.46-1.87 mmol/L) in nondiabetics; P < 0.02]; free cholesterol (FC) [0.97 mmol/L (0.60-1.26 mmol/L) in type I DM compared with 0.62 mmol/L (0.37-0.75 mmol/L) in nondiabetics; P < 0.05), and cholesteryl ester (CE) [1.90 mmol/L (1.44-3.33 mmol/L) in type I DM compared with 1.01 mmol/L (0.83-1.24 mmol/L) in nondiabetics; P < 0.02), triglyceride (TG) (1.06 [0.50-1.91) mmol/L in type I DM compared with 0.29 [0.25-0.36] mmol/l in nondiabetics; P < 0.001), phospholipid (PL) (2.52 [1.73-3.03) mmol/L in type I DM compared with 1.34 [1.27-1.48] mmol/L in nondiabetics; P < 0.01], and the apolipoproteins A-I and B had significantly higher concentrations in type I DM. In umbilical venous cord blood, ratios of HDL-TC and HDL-PL to apo AI, reflecting the lipid content of HDL, were reduced when the mother had type I DM during pregnancy (P < 0.02 and P < 0.0001, respectively). These results indicate that maternal type I DM may lead to a fetal serum lipoprotein composition more closely resembling that seen in the adult. In type I DM, maternal TG and PL and fetal TC, TG, PL, CE, and FC were correlated to NEFA levels (P < 0.05), but not to glucose, insulin secretion, or maternal control of type I DM. These data suggest that the enhanced supply of NEFA to the fetus in type I DM pregnancies may drive the synthesis of cholesterol as well as TGs and PLs. 相似文献
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An 84-year-old male presented to the emergency room with the chief complaint of painful, swollen penis following the use of a constriction ring to maintain penile erection. A high fever, chills and hypotension were recognized. Septic shock was presumed, and administration of antibiotics was started. Microbiologic cultures revealed Escherichia coli in blood. We herein report a rare but serious complication accompanying incarceration of the penis. 相似文献
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The purpose of this study was to explore the glycemic control and influencing factors in outpatients newly diagnosed with non-insulin-dependent diabetes mellitus (NIDDM). By purposeful sampling, data were collected from 130 outpatients with NIDDM at one medical center in Kaohsiung. The results indicated: (1) the mean value for HbA1C was 7.12%; and 63.1% of the patients belonged to moderate to well controlled group; (2) male patient's HbA1C value was significantly lower than female patient's; patients with no religious belief also had a lower HbA1C value than patients with a religious background; (3) there were strongly negative correlations between self-care behaviors, social support, and self-efficacy and HbA1C; (4) using a multiple stepwise regression analysis, religious belief and self-care behaviors were found to explain 10.9% variance of HbA1C level. The results of this study could be used as a reference for diabetes health education program. 相似文献
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PURPOSE: The purpose of this investigation was to evaluate the surgeon's ability to assess various types of globe injury, to determine the force necessary to rupture the globe with these types of injuries, and to determine typical orbital retraction forces used in the clinical setting. MATERIALS AND METHODS: Forty-four enucleated globes from recently killed cows were divided into four equal groups-one uninjured control group, one group with a through-and-through scleral laceration, another group with a subtotal scleral laceration, and the last group with an 18-gauge needle perforation. Twenty-seven boarded or board eligible oral and maxillofacial surgeons were asked to assess one sample from each of the four groups. They were then asked to retract a simulated globe on a custom-fabricated jig to determine clinical retraction forces. Ten globes from each of the four groups were then subjected to forces until rupture on an Instron 8501M mechanical testing unit. Accuracy of the clinical assessment was determined, and means and standard deviations of the retraction forces and globe rupture forces were derived. RESULTS: Through-and-through lacerations were assessed by surgeons with 100% accuracy, subtotal lacerations with 96% accuracy, uninjured globes with 74% accuracy, and perforated globes with 15% accuracy. Globe rupture occurred at 16.72+/-7.87 kg in the control group, 20.36+/-7.87 kg in the perforated group, 15.38+/-6.06 kg in the subtotal laceration group, and 4.94+/-2.56 kg in the through-and-through laceration group. Statistically significant differences (P < .001) were noted between the total laceration group and all other groups. The mean retraction force was 0.35+/-0.47 kg, which was statistically less than the force used in all of the rupture groups (P < .001). CONCLUSIONS: Severe injuries (through-and-through lacerations) were assessed with 100% accuracy by the clinicians, and less severe injuries with less accuracy. Rupture forces for globes with perforations and subtotal lacerations were no different than for the control group, but substantially less than for the total laceration group. The simulated clinical retraction forces were substantially more than the rupture forces in all of the groups, including the through-and-through laceration group. 相似文献
48.
A long repetitive DNA sequence (OtY8) has been cloned from male chinook salmon and its genomic organization has been characterized. The repeat has a unit length of 8 kb and is present approximately 300 times per diploid male nucleus. All internal fragments within the 8-kb repeat segregate from father to son, suggesting that the entire repeat unit is located on the Y chromosome. The organization of this sequence into an 8-kb repeat unit is restricted to the Y chromosome, as are several male-specific repeat subtypes identified on the basis of restriction-site variation. The repeat possesses only weak internal sequence similarities, suggesting that OtY8 has not arisen by duplication of a smaller repeat unit, as is the case for other long tandem arrays found in eukaryotes. Based on a laddered pattern arising from partial digestion of genomic DNA with a restriction enzyme which cuts only once per repeat unit, this sequence is not dispersed on the Y chromosome but is organized as a head-to-tail tandem array. Pulse-gel electrophoresis reveals that the direct-tandem repeats are organized into at least six separate clusters containing approximately 12 to 250 copies, comprising some 2.4 Mb of Y-chromosomal DNA in total. Related sequences with nucleotide substitutions and DNA insertions relative to the Y-chromosomal fragment are found elsewhere in the genome but at much lower copy number and, although similar sequences are also found in other salmonid species, the amplification of the repeat into a Y-chromosome-linked tandem array is only observed in chinook salmon. The OtY8 repetitive sequence is genetically tightly associated with the sex-determination locus and provides an opportunity to examine the evolution of the Y chromosome and sex determination process in a lower vertebrate. 相似文献
49.
RH Baltz 《Canadian Metallurgical Quarterly》1998,6(2):76-83
The genetic manipulation of Streptomyces species has been facilitated by the development of versatile cloning vectors, robust gene transfer systems and transposable elements. These molecular genetic tools have been used to construct antibiotic-producing strains with improved properties and recombinants for the production of hybrid glycopeptide and macrolide antibiotics, novel anthelminthic agents and novel cytotoxic anthracyclines. 相似文献
50.
Surface characteristics of the bovine oocyte and its investments before, during, and after maturation, and fertilization in vitro were evaluated by scanning electron microscopy (SEM). Oocyte diameters were also measured during SEM analysis of the oocyte. The cumulus cells manifested a compact structure with minimal intercellular spaces among them in the immature oocytes. These became fully expanded with increased intercellular spaces after maturation in vitro, but contracted again after fertilization. The zona pellucida (ZP) showed a fibrous, open mesh-like structure in the maturing and matured oocytes. The size and number of meshes on the ZP decreased dramatically after fertilization. The vitelline surface of immature oocytes was characterized by distribution of tongue-shaped protrusions (TSPs) varying in density. After 10 and 22 hr of maturation incubation, oocyte surface microvilli (MV) increased to become the predominant surface structure, and TSPs decreased substantially. The vitelline surface of fertilized oocytes (at 6 and 20 hr) was similar to that of the matured oocytes, but unfertilized oocytes had less dense MV than did fertilized oocytes (at 20 hr). The diameter of the oocytes decreased from 99 to 80 microns during maturation and increased to 106 microns after insemination (P < 0.05). Membrane maturation was characterized by surface changes from a TSP-predominant pattern to a MV-predominant pattern. Thus, the bovine oocyte maturation process was found to involve the expansion of cumulus cells and the maturation of the ZP, which changes dramatically upon fertilization. Also, volumetric changes occurred in ooplasm processed for SEM following oocyte maturation and insemination. 相似文献