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991.
Al-Saleh E Nandakumaran M Al-Shammari M Makhseed M Sadan T Harouny A 《Archives of gynecology and obstetrics》2005,271(3):212-217
Objective The objective was to assess the status of essential trace elements such as copper, iron, molybdenum, selenium and zinc in insulin-dependent diabetic pregnancies at term and to compare the data with a control group. Fetal-maternal ratios of the elements and copper:zinc ratio were also computed in the control and study populations.Methodology Samples from maternal vein, umbilical artery and umbilical vein of diabetic and control women were collected at the time of spontaneous delivery or cesarean section and activities of trace elements evaluated by atomic absorption spectrophotometry.Results Cu, Fe, Mo, Se and Zn concentrations in maternal venous blood averaged 2,156, 2,020, 13, 102 and 656 g/l in control women (n=17) while in the diabetic group (n=14), the corresponding values for the trace elements averaged 3,135, 3,675, 15, 85 and 628 g/l respectively. Values for copper and molybdenum were significantly higher (p<0.05) in the study group compared to control while those of zinc, iron and selenium were not significantly different (p>0.05). Iron and molybdenum values were significantly higher (p<0.05) and that of zinc significantly lower (p<0.05) in umbilical arterial samples of diabetic group compared to controls. In the case of molybdenum, copper the values were significantly higher (p<0.05) in umbilical venous samples of diabetic group compared to that of control. Significant differences in Cu:Zn ratio of maternal venous and umbilical samples and fetal-maternal ratios of some elements were noted between control and study group as well.Conclusion We speculate that altered status of some essential trace elements and altered antioxidant mineral ratio observed in insulin dependent diabetic patients could have deleterious influences on the health of the mother as well as the fetus and newborn. 相似文献
992.
Myotonic dystrophy type 1 (DM1) is associated with both skeletal and cardiac muscle involvement. The aim of the present study was to determine whether familial clustering is observed in the severity of muscle involvement in DM1. We evaluated 51 sibling groups constituting 112 patients with genetically-verified DM1. The siblings were similar to each other in age, cytosine-thymine-guanine (CTG) repeat length, age at disease onset, muscular impairment rating score, and electrocardiographic markers of cardiac conduction disease. After adjusting for the similarities between siblings in age and CTG repeat length, the siblings remained similar to each other in measures of both skeletal and cardiac muscle involvement. These results suggest that factors other than CTG repeat length play a role in the severity and progression of the degenerative skeletal and cardiac muscle disease in DM1. 相似文献
993.
Clare DJ Wirth MA Groh GI Rockwood CA 《The Journal of bone and joint surgery. American volume》2001,(4):593-600
Current indications for shoulder arthrodesis include posttraumatic brachial plexus injuries, paralysis of the deltoid muscle and rotator cuff, chronic infection, failed revision arthroplasty, severe refractory instability, and bone deficiency following resection of a tumor in the proximal aspect of the humerus. The trapezius, levator scapulae, serratus anterior, and rhomboid muscles must be functional to optimize the functional result following shoulder arthrodesis. A consensus has not been reached concerning the ideal position of the shoulder arthrodesis, although excessive abduction or flexion has been associated with chronic postoperative pain. Decortication of both the acromiohumeral and the glenohumeral surfaces to increase the surface area available for arthrodesis is the most common means for obtaining successful fusion. Although there are numerous methods for stabilization of a shoulder arthrodesis, the most popular method today is probably the AO technique with either a single plate or double plates. 相似文献
994.
Peroxisome proliferator-induced mitogenesis is believed to play a role in
hepatocarcinogenesis, but it has not been possible to demonstrate high
level induction of DNA synthesis by peroxisome proliferators in cultured
hepatocytes. We now show that four structurally dissimilar peroxisome
proliferators (methylclofenapate, Wy-14 643, tetradecyl-3- thia acetic acid
and clofibrate) cause high level induction of DNA synthesis in primary
cultures of rat hepatocytes, routinely 7-9 fold above control, with up to
29% of cells undergoing S-phase. Peroxisome proliferators induce DNA
synthesis rapidly, with maximal response 24 h after dosing [compared with
48 h for epidermal growth factor (EGF)]; indeed, peroxisome proliferators
were mitogenic in a chemically defined medium, i.e. with no added exogenous
growth factors. EGF-treated hepatocytes that had undergone DNA synthesis
comprised 23% binucleated cells, whereas hepatocytes induced into S-phase
by peroxisome proliferators contained only 3% binucleated cells,
demonstrating a distinct response of hepatocytes to peroxisome
proliferators and EGF. The presence of a glucocorticoid was essential for
peroxisome proliferator-induced DNA synthesis, but not for EGF-induced DNA
synthesis, demonstrating that the requirement for glucocorticoids is
selective for peroxisome proliferators. Hydrocortisone was shown to induce
the expression of peroxisome proliferator activated receptor- alpha (PPAR
alpha), and we propose that it is the glucocorticoid- induced expression of
PPAR alpha that is essential for peroxisome proliferator mitogenesis. This
in vitro system provides a powerful tool for investigating the mechanism
and role of peroxisome proliferator- induced mitogenesis in liver growth
and carcinogenesis.
相似文献
995.
The coordinate regulation of DNA synthesis and suppression of apoptosis was
investigated in a rat hepatocyte cell culture system which supports high
level induction of DNA synthesis by the peroxisome proliferator,
methylclofenapate (MCP) (Plant, N.J. et al., 1998, Carcinogenesis, 19,
925-931). The peroxisome proliferators are hepatocyte mitogens in
chemically defined media: glucocorticoid-induced PPARalpha is linked to
peroxisome proliferator mitogenesis (Plant, N.J. et al., 1998,
Carcinogenesis, 19, 925-932). Phenobarbital (PB) induced moderate induction
of DNA synthesis (200-300% of control), but the peak of induction was 40 h
after treatment. In hepatocytes that had undergone DNA synthesis, PB
increased the proportion of binucleates by 200-300%. Both PB and MCP were
able to suppress apoptosis in a dose-dependent manner, while the endogenous
mitogen epidermal growth factor failed to suppress apoptosis. The
suppression of apoptosis by MCP was reversible; withdrawal of MCP led to
rapid induction of apoptosis. The presence of hydrocortisone is required
for suppression of apoptosis by peroxisome proliferators, but not for PB.
MCP failed to suppress apoptosis in primary cultures of guinea-pig
hepatocytes. Comparison of the stability of hepatocytes labelled with
bromodeoxyuridine (BrdUrd) and [3H]thymidine revealed that approximately
40% of cells labelled with BrdUrd were lost over a period of 14 days,
whereas cells labelled with thymidine remained stable over this period.
Hepatocytes were therefore treated with MCP, labelled with [3H]thymidine,
maintained for 14 days, and peroxisome proliferator withdrawn. While the
apoptotic index in unlabelled cells was 1.7%, no apoptosis was detected in
labelled cells. In order to compare the mechanism of suppression of
apoptosis, hepatocytes were cultured in the presence of either PB or MCP
for 14 days. When MCP was substituted for PB in cells cultured in the
presence of PB, the monolayer was maintained, but when PB was used to
replace MCP in cells cultured in the presence of MCP, the monolayer of
hepatocytes degenerated rapidly. The results demonstrate mechanistic
differences in the coordinate regulation of cell growth and apoptosis in
hepatocytes by PB and MCP.
相似文献
996.
Estrogens, which have been associated with several types of human and
animal cancers, can induce tumor angiogenesis in the pituitary of Fischer
344 rats. The mechanistic details of tumor angiogenesis induction, during
estrogen carcinogenesis, are still unknown. To elucidate the role of
estrogen in the regulation of tumor angiogenesis in the pituitary of female
rats, the density of blood vessels was analysed using factor VIII related
antigen (FVIIIRAg) immunohistochemistry and the expression of vascular
endothelial growth factor/vascular permeability factor (VEGF/VPF) was
examined by Western blot and immunohistochemical analysis. The expression
of VEGF receptor (VEGFR-2/Flk-1/KDR) was also examined by
immunohistochemistry. The results demonstrated that 17beta-estradiol (E2)
induces neovascularization, as well as the growth and enlargement of blood
vessels after 7 days of exposure. The high tumor angiogenic potential was
associated with an elevated VEGF/VPF protein expression in the E2 exposed
pituitary of ovariectomized (OVEX) rats. VEGF/VPF and FVIIIRAg
immunohistochemistry and endothelial specific lectin (UEA1) binding
studies, indicate that the elevation of VEGF protein expression initially
occurred in both blood vessels and non-endothelial cells. After 15 days of
E2 exposure, VEGF/VPF protein expression, in the non- endothelial cell
population, sharply declined and was restricted to the blood vessels. The
function of non-endothelial-derived VEGF is not clear. Furthermore,
immunohistochemical studies demonstrated that VEGFR- 2 (flk-1/KDR),
expression was elevated significantly in the endothelial cells of
microblood vessels after 7 days of E2 exposure. These findings suggest that
over expression of VEGF and its receptor (VEGFR-2) may play an important
role in the initial step of the regulation of estrogen induced tumor
angiogenesis in the rat pituitary.
相似文献
997.
Bifidobacterium longum and lactulose suppress azoxymethane-induced colonic aberrant crypt foci in rats 总被引:5,自引:0,他引:5
Bifidobacterium longum has been shown to afford protection against colon
tumorigenesis. Lactulose, a keto analog of lactose, serves as a substrate
for preferential growth of Bifidobacterium. It is not known whether feeding
lactulose along with B. longum will have any advantage over feeding of B.
longum alone. To test this combination effect, 61 male Fisher 344 weanling
rats were divided into four groups of 15 rats each (16 in the control
group) and assigned to one of the following four diets for 13 weeks: (i)
AIN76A (control, C); (ii) C + 0.5% B. longum (C+Bl, containing 1 x 10(8)
viable cells/g feed); (iii) C + 2.5% lactulose (C+L); (iv) C + 0.5% B.
longum + 2.5% lactulose (C+Bl+L). All animals received a s.c. injection of
azoxymethane at 16 mg/kg body wt at 7 and 8 weeks of age. Colons of 10 rats
from each dietary group were analyzed for aberrant crypt foci (ACF), which
are preneoplastic markers. Colonic mucosa and livers from five rats were
analyzed for glutathione S-transferase (GST, a Phase II enzyme marker).
Results indicate that feeding of lactulose and B. longum singly and in
combination reduces the number of ACF (P = 0.0001) and the total number of
aberrant crypts significantly (P = 0.0005). The total number of ACF in
diets C, C+Bl, C+L and C+Bl+L were 187 +/- 9, 143 +/- 9, 145 +/- 11 and 97
+/- 11 respectively. There was no significant difference in weight gain
among treatments. Colonic mucosal GST levels were significantly (P = 0.05)
higher in the Bl and L groups compared with group C. Initially there was a
mild diarrhea in lactulose-fed rats. There was a positive correlation
between higher cecal pH and number of ACF. Results of the study indicate
that Bifidobacterium and lactulose exert an additive antitumorigenic effect
in rat colon.
相似文献
998.
Nelson RM Stebor AD Groh CM Timoney PM Theobald KS Friedman BA 《Blood pressure monitoring》2002,7(2):123-129
BACKGROUND: New software (SuperSTAT(R) algorithm) with enhancements aimed at shorter determination times was developed for a non-invasive blood pressure (NIBP) device and a clinical evaluation was conducted to verify accuracy. OBJECTIVE: To determine the accuracy of the new algorithm according to ANSI/AAMI SP10-1992 and SP10A-1996 American National Standard for Electronic or Automated Sphygmomanometers. METHODS: The blood pressure values obtained from the test device were compared to the intra-arterial blood pressure reference standard (IBP). RESULTS: The NIBP and IBP comparisons for systolic, diastolic, and mean arterial pressure met the 1992 ANSI/AAMI accuracy standards by being within a mean difference of +/- 5 mmHg and standard deviation of < or = 8 mmHg. CONCLUSION: Non-invasive blood pressure determinations taken with the new algorithm, developed to provide greater patient comfort due to faster determinations, were accurate when compared to neonatal IBP. 相似文献
999.
Groh MJ Nguyen NX Küchle M Naumann GO 《Klinische Monatsbl?tter für Augenheilkunde》2002,219(1-2):37-39
BACKGROUND: Epithelial ingrowth to the anterior chamber is a rare event after ocular injury or intraocular surgery. We report on four patients with primary cystic epithelial ingrowth (with primary curative cystic formation when treated with block excision) who underwent Nd:YAG-laser puncture of the cysts elsewhere. This treatment led to a change from a cystic to a diffuse form with a poor prognosis for the eye. PATIENTS: Three women and one man were seen in our outpatient department. Cystic epithelial ingrowth happened after intraocular surgery (1 x goniotomy, 2 x cataract surgery) or perforating injury (1 x). All four patients were treated elsewhere with puncture of the cysts (by Nd:YAG-laser). At first presentation in our department a change of cystic to diffuse epithelial ingrowth was noticed. Curative treatment by block excision was no longer possible. Diffuse epithelialisation of the anterior chamber resulted in secondary glaucoma with a poor prognosis. CONCLUSIONS: In our experience puncture of intraocular epithelial cysts may lead to a transformation to diffuse epithelial ingrowth with possible loss of the eye. Surgical opening of the cyst or subtotal excision is therefore contraindicated from our point of view. In case of cystic epithelial ingrowth of less than 5 hours of the limbal circumference, block excision in toto is indicated. 相似文献
1000.
Hybrid subtraction angiography can provide a higher percentage of two-view examinations of the carotid bifurcation. Unfortunately, hybrid images are lower in signal-to-noise ratio (S/N) than temporal subtraction angiographic images and are often described as "noisy." The present study was designed to determine if the lower S/N of hybrid subtraction angiography could be restricted to the contralateral carotid bifurcation by "splicing" a small hybrid region of interest into a larger temporal image. Twenty-two selected images were examined on four image quality scales by seven readers. Similarity of reader scoring was characterized by cluster analysis and was good. Ipsilateral carotid arteries were preferred as temporal images, and contralateral carotid arteries were preferred as hybrid images. The splice image was preferred over both. The splice image retained the superiority of temporal subtraction angiography in the region of the ipsilateral carotid artery and incorporated the superiority of hybrid subtraction angiography in the region of the contralateral carotid artery. The splice image incorporated the best features of both image modalities. 相似文献