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Differences in blood pregnenolone and dehydroepiandrosterone levels between schizophrenia patients and healthy subjects. 总被引:1,自引:0,他引:1
Michael Ritsner Rachel Maayan Anatoly Gibel Abraham Weizman 《European neuropsychopharmacology》2007,17(5):358-365
BACKGROUND AND OBJECTIVE: Contradictory and confusing reports on serum dehydroepiandrosterone (DHEA) levels in schizophrenia led us to compare the serum concentration of its precursor, pregnenolone (PREG), between medicated schizophrenia patients and healthy subjects. The neurosteroid levels were monitored for two months and the relationship of these neurosteroids with schizophrenic symptomatology, emotional distress, and anxiety was examined. METHOD: We determined blood levels of PREG, and DHEA in 15 schizophrenia patients and 12 healthy controls at four time points: at the start of the study, after 2, 4 and 8 weeks. Analysis of covariance and canonical correlations across four time points were applied. RESULTS: Controlling for age, serum concentrations of PREG were lower, while the DHEA level and the molar ratio values of DHEA/PREG were higher in schizophrenia patients compared to healthy controls. Both levels of PREG and DHEA and their molar ratio did not change significantly during the study's period either among schizophrenia patients or healthy controls. The blood levels of PREG appear to be associated with trait-anxiety scores in the schizophrenia patients, while associations of clinical symptoms with two neurosteroids did not reach a significant level when the confounding effect of emotional distress, and anxiety scores was controlled. CONCLUSION: Low serum pregnenolone concentrations in schizophrenia appear to be associated with trait-anxiety scores independent of symptoms. Further research into the role of pregnenolone in schizophrenia is warranted. 相似文献
3.
Since potassium ions are very important in surgical pathology and the course of the postoperative period, the authors determined erythrocyte potassium in 211 patients (37 in the control group and in 174 in the pathological group). The statistically evaluated results were compared for both groups and the correlations of serum and red cell potassium with the acid-base status were studied. The authors used a Marongiu's modified method of potassium determination in a erythrocyte hemolysate with a flame photometer. The mean values for both the control and pathological groups were 84.61 (SD 5.24) and 85.98 (SD 9.10), respectively. The correlation of serum and erythrocyte potassium is subject to many influences and occurs only in the limited pH and HCO3 intervals (pH 7.4 +/- 0.5 and HCO3 21 +/- 2.0) so that it is insignificant even for the control group. If a concentration exceeding two standard deviations is considered abnormal and a deficit percentage is calculated, it is possible to approximate the total body deficit from the expected values of 50-55 mM/kg and to start proper replacement. In evaluating the results, precise laboratory work must be performed and the clinical condition must be taken into account. Therefore, the method of erythrocyte potassium determination is not suitable for routine work and is used only in case of serum potassium excess values and during prolonged postoperative parenteral treatment. 相似文献
4.
Debbie M. Popovich MSN RN CPNP Allison McAlhany MSN RN CPNP 《Newborn and Infant Nursing Reviews》2004,4(1):51
Chlamydia trachomatis is the most prevalent sexually transmitted microbial infection in the United States. The CDC estimates that 3 million people are infected annually, with approximately 50% of infected men and 75% of infected women having few or no recognized symptoms. C. trachomatis is frequently transferred from mother to infant, and the maternal-infant transfer of this disease may have negative consequences for the newborn, such as prematurity, pneumonia, and conjunctivitis. Ocular prophylaxis with silver nitrate and or antibiotics is ineffective in preventing neonatal chlamydial conjunctivitis. By increasing awareness of the potential adverse consequences, initiating screening and treatment of pregnant women, and advocating for newborn assessment and treatment, nurses can enhance the quality of care for mothers and their infants. 相似文献
5.
Alexey V. Mazurov Dimitry V. Vinogradov Svetlana G. Khaspekova Anatoly V. Krushinsky Ludmila V. Gerdeva Sergei A. Vasiliev 《European journal of haematology》1996,57(1):38-41
Abstract: Patient B.G. is a 29-yr-old female with a lifelong bleeding disorder characterized clinically by a highly increased bleeding time, menorrhagias, long-lasting bleeding after cuts and tooth extractions and large post-traumatic haematomas. Her coagulation tests were within normal range, platelet count was 140,000–160,000 per μl, but platelet function was impaired as demonstrated by the absence of collagen-induced aggregation, although no abnormalities were detected in aggregation response to ADP and ristocetin. Morphologically her platelets were characterized by gigantic size – average profile area was about 2.5 times higher than that of control donors, and severe deficiency of α-granules – only 16% of their number in control donors. These features taken together indicated the diagnosis of grey platelet syndrome. As has been shown by quantitative immunoblotting, patient's platelets contained small amounts of α-granule membrane protein P-selectin – about 15% of that in control donors. The content of plasma membrane glycoproteins IIb–IIIa and Ib was not reduced, suggesting the specific deficiency of α-granule membrane protein. Thus, B.G. is the second patient described in the literature (see also Lages et al, J Clin Invest 1991: 87: 919–929) with combined deficiency of α-granules and P-selectin. 相似文献
6.
Chromosomal breakage in normal and fragile X subjects using low folate culture conditions. 总被引:2,自引:0,他引:2 下载免费PDF全文
To investigate whether the fragile X syndrome is associated with a generalised chromosomal instability, we compared the frequency and distribution of chromosomal breakage in lymphocytes grown in low folate medium from normal subjects and from patients with the syndrome. Although low folate conditions increased the rate of chromosome breakage, no difference in frequency or distribution of chromosomal breakage was found between the two groups. This suggests that the fragile X syndrome is not associated with a generalised chromosome instability expressed in folate deficient medium and assessed in terms of chromosomal breakage. 相似文献
7.
Alexander Mülsch Markus Hecker Petr I. Mordvintcev Anatoly F. Vanin Rudi Busse 《Naunyn-Schmiedeberg's archives of pharmacology》1993,347(1):92-100
Summary The molecular mechanism(s) underlying the vasodilator activity of CAS 936 (3-(cis-2,6-dimethylpiperidino)-N-(4-methoxybenzoyl)-sydnonimine) and its metabolites 3-(cis-2,6-dimethylpiperidino)-sydnonimine (C87 3754) and N-(cis-2,6-dimethylpiperidino)-N-nitroso-2-aminoacetonitril (C873786) was investigated. These compounds were tested for their relaxant activity in isolated rabbit arterial segments, activation of purified soluble guanylyl cyclase and release of nitric oxide (NO) in vitro and in vivo. C873754 and C873786 inhibited the noradrenalin-induced contraction and increased the cyclic GMP content of endothelium-denuded rabbit aortic and femoral segments, whereas CAS 936 was without effect. Similarly, both metabolites, but not CAS 936, activated purified soluble guanylyl cyclase (EC50 about 30 M) and released NO in buffered aqueous solutions, as detected by electron spin resonance (esr) spectrometry. Both in vitro and in vivo an accumulation of NO was detected by esr spectrometry in vascular tissues exposed to the metabolites of CAS 936, whereas a significant release of NO from CAS 936 was only detected in the isolated rabbit liver, but not in vascular tissue. It is conceivable, therefore, that the metabolites of CAS 936 appearing in the systemic circulation after hepatic biotransformation induce vasodilatation by release of NO and activation of soluble guanylyl cyclase in vascular smooth muscle. Moreover, the activation of soluble guanylyl cyclase in vitro by the metabolites of CAS 936 was significantly enhanced by co-incubation with certain particulate fractions from bovine aortic endothelial and smooth muscle cells. Thus, an enzymic release of NO from these metabolites in addition to their spontaneous decomposition may play a significant role for their vasodilator activity in vivo.Correspondence to A. Mülsch at the above address 相似文献
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Soltsman S Russo P Greenshpun A Ben-Ami M 《Journal of minimally invasive gynecology》2008,15(4):508-510
Abdominal compartment syndrome is a consequence of increased intraabdominal pressure. It can be triggered by inflammation, hemorrhage, chemical peritonitis, or prolonged insufflations during laparoscopy. It is a well-known phenomenon for intensive care specialists, but gynecologists are relatively unfamiliar with its occurrence. A woman with heterotopic pregnancy underwent urgent laparoscopy because of abdominal hemorrhage. The postoperative course was complicated by abdominal pain, ascites, bowel dysfunction, and renal failure, which resolved rapidly after catheterization and paracentesis. In this case, abdominal compartment syndrome developed after unremarkable laparoscopy, and appeared to be triggered by change of progesterone formulation. Decompression by paracentesis was lifesaving, and led to rapid resolution of the symptoms. 相似文献
10.
Vadim Sufiiarov Danil Erutin Artem Kantyukov Evgenii Borisov Anatoly Popovich Denis Nazarov 《Materials》2022,15(12)
Original 1CP powder was studied and it was founded that powder material partially consists of the amorphous phase, in which crystallization begins at 450 °C and ends at 575 °C. Selective laser melting parameters were investigated through the track study, and more suitable ones were found: laser power P = 90, 120 W; scanning speed V = 1200 mm/s. Crack-free columnar elements were obtained. The sample obtained with P = 90 W, contains a small amount of amorphous phase. X-ray diffraction of samples shows the presence of α-Fe(Si) and Fe2B. SEM-image analysis shows the presence of ordered Fe3Si in both samples. Annealed samples show 40% less microhardness; an annealed sample containing amorphous phase shows higher soft-magnetic properties: 2.5% higher saturation magnetization, 35% higher residual magnetization and 30% higher rectangularity coefficient. 相似文献