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111.
This study was performed to determine whether peritoneal T cells are suppressed in the CD4+ or CD8+ T cell subpopulation and whether they are Th1 or Th2 predominant in women with endometriosis. Immune cells in the peritoneal fluid (PF) were obtained from women undergoing laparoscopy for endometriosis or tubal ligation. Three-colour flow cytometry was utilized for immunophenotyping of peritoneal fluid mononuclear cells (PFMC). Concentrations of interleukin (IL)-4, IL-5 and interferon-gamma (IFN-gamma) produced by PFMC with and without mitogen stimulation and concentrations of IL-10 and IL-12 were measured in PF. The peritoneal T lymphocytes were predominantly of the Th1 type that produced much more IFN-gamma but less IL-4 or IL-5 in women with or without endometriosis. The decrease in peritoneal lymphocytes was significant in the HLA-DR+ CD4+ CD3+ subpopulation and the concentrations of peritoneal IL-10 and IL-12 were significantly elevated in women with early stage endometriosis. There was impaired IL- 5 production by PFMC after phytohaemagglutinin stimulation in women with advanced stage endometriosis. We concluded that the activated peritoneal CD4+ Th1 cells from the women with endometriosis were decreased in number. The suppression of these T cells may be due to the elevation of IL-10 and IL-12 in the peritoneal fluid.   相似文献   
112.
The aim of this study was to determine the prognostic value of single and paired measurements of serum concentrations of human chorionic gonadotrophin (HCG) for successful pregnancy following in-vitro fertilization (IVF) and tubal embryo transfer (TET). We analysed serum HCG concentrations 15 and 22 days after IVF or TET in 198 conception cycles. Cut-off values of serum HCG were determined by a receiver operating characteristic (ROC) curve. On the basis of single HCG samples on day 15 (HCG15) after transfer, using a cut-off value of HCG15 = 150 mIU/ml, the sensitivity was 71% and the specificity was 77%. The positive predictive value (HCG15 > or = 150 mIU/ml indicating a normal pregnancy) was 89%, while the negative predictive rate (HCG15 < 150 mIU/ml indicating an abnormal pregnancy) was 51%. Patients with HCG15 < 150 mIU/ml but HCG22/HCG15 ratio > or = 15, still had a 90% chance of normal pregnancy. However, in patients with HCG15 < 150 mIU/ml and an HCG22/HCG15 ratio < 15, there was an 84% chance of an abnormal pregnancy. We conclude that a single HCG15 determination combined with the ratio of HCG22 to HCG15 has a higher diagnostic accuracy for prediction of pregnancy outcome than either analysis alone.   相似文献   
113.
To explore the role of nitric oxide (NO) and oxidative stress in the pathogenesis of adhesion formation and in endometriosis-associated infertility, we examined the peritoneal total antioxidant status (TAS) and the concentrations of products of NO metabolism in women with endometriosis (early stage, n = 12; advanced stage, n = 12) and in fertile women without endometriosis (n = 10). Peritoneal CA 125 and oestrogen and progesterone concentrations were also measured to examine their contributions to TAS and the production of NO. We failed to demonstrate any significant difference in TAS and in the products of NO metabolism in peritoneal fluids among women with early and advanced stages of endometriosis compared with fertile women without endometriosis during the early follicular phase. TAS and the concentration of the products of NO metabolism were not related to concentrations of CA 125, oestrogen or progesterone. The concentration of CA 125 in serum, but not in peritoneal fluid, was positively correlated with the severity of endometriosis. The volume of peritoneal fluid and the progesterone concentration were significantly increased in the group with advanced endometriosis. TAS and the concentration of the products of NO metabolism did not increase in peritoneal fluids from women with endometriosis during the early follicular phase. Their role in the pathophysiology of endometriosis needs to be explored further.   相似文献   
114.
Normal human spermatozoa carry either the X or the Y chromosome. The differences between X and Y spermatozoa (X and Y haploid cells) may exist in two areas: the different chromosomes (i.e. different kinds and numbers of genes) and the different sperm structures and functions (i.e. different genetic expression). The aim of this study was to determine whether there are any size between X and Y spermatozoa and whether sperm size and shape varies between men. Identification of the Y (and X inferred) status of individual spermatozoa was carried out by polymerase chain reaction (PCR), amplifying the putative testis- determining gene (SRY) together with a control gene (ZP3). PCR amplification of 871 out of 895 (97.3%) single motile spermatozoa showed that 444 (51.0%) were Y and 427 (49.0%) were X-bearing spermatozoa. Of 233 normally-shaped but immobilized spermatozoa, 217 (93.1%) were photographed and measured. Statistically, the length, perimeter and area of the sperm heads, and the length of the sperm necks and tails of X-bearing spermatozoa were significantly larger and longer than those of Y-bearing spermatozoa. Some peculiarities (or variations) in the X and Y sperm shape and size in individual donors were found. The pre-screening by micro-measurement of these specific haploid characteristics of individual spermatozoa in different donors, which may be closely related to their different genetic conditions (or diseases), may be important in human medicine and animal husbandry, especially in sperm prefertilization diagnosis.   相似文献   
115.
A 68-year-old Chinese man presented with an eight-month history of pyrexia of unknown origin and chronic sinusitis despite multiple courses of antibiotics. He underwent extensive investigations, including workups for infections, chronic granulomatous diseases and malignancy. Nasal biopsies were performed twice under local anaesthesia, but did not show any evidence of malignancy. Eventually, the patient was diagnosed with natural killer (NK)/T-cell lymphoma, nasal variant, based on histopathological findings from harvested deep tissue obtained via functional endoscopic sinus surgery. This study highlights that, for patients presenting with pyrexia of unknown origin and nasal symptoms, NK/T-cell lymphoma must be considered as a differential diagnosis. Generous amounts of tissue should be harvested under general anaesthesia rather than limited tissue under local anaesthesia, in order to facilitate and ensure a definitive diagnosis.  相似文献   
116.

BACKGROUND AND PURPOSE

Acute exacerbations of chronic obstructive pulmonary disease (COPD), which are often associated with respiratory infections, are defined as a worsening of symptoms that require a change in medication. Exacerbations are characterized by a reduction in lung function, quality of life and are associated with increased pro-inflammatory mediators in the lung. Our aim was to develop an animal model to mimic aspects of this exaggerated inflammatory response by combining key etiological factors, tobacco smoke (TS) and bacterial lipopolysaccharide (LPS).

EXPERIMENTAL APPROACH

Rats were exposed to TS for 30 min twice a day for 2 days. On day 3 animals were exposed to LPS for 30 min followed by exposure to TS 5 h later. Inflammation, mucus and lung function were assessed 24 h after LPS.

KEY RESULTS

Neutrophils, mucus, oedema and cytotoxicity in lung and/or bronchoalveolar lavage was increased in animals exposed to combined LPS and TS, compared with either stimulus alone. Lung function was impaired in animals exposed to combined LPS and TS. Inflammatory cells, oedema and mucus were unaffected by pretreatment with the corticosteroid, budesonide, but were reduced by the phosphodiesterase 4 selective inhibitor roflumilast. Additionally, lung function was improved by roflumilast.

CONCLUSIONS AND IMPLICATIONS

We have established an in vivo model mimicking characteristic features of acute exacerbations of COPD including lung function decline and increased lung inflammation. This model may be useful to investigate molecular and cellular mechanisms underlying such exacerbations, to identify new targets and to discover novel therapeutic agents.  相似文献   
117.
BACKGROUND: Studies have suggested that aspartame (ASP) ingestion is implicated in neurological problems. AIM: The aim of this study was to evaluate rat frontal cortex Na+, K+ -ATPase and Mg2+ -ATPase activities after incubation with ASP or each of its metabolites, phenylalanine (Phe), methanol (MeOH) and aspartic acid (asp) separately. METHOD: Suckling rat frontal cortex homogenates or pure Na+, K+ -ATPase were incubated with ASP metabolites. Na+, K+ -ATPase and Mg2+ -ATPase activities were measured spectrophotometrically. RESULTS: Incubation of frontal cortex homogenate or pure Na+, K+ -ATPase with various ASP concentrations as expected in the cerebrospinal fluid (CSF) after ASP consumption of 34, 150 or 200mg/kg, decreased the frontal cortex enzyme activity by 33%, 53% or 57%, respectively, whereas pure enzyme was remarkably stimulated. Moreover, incubation of frontal cortex homogenate with each one of the expected ASP metabolites in the CSF, except MeOH, which are related to the intake of the above mentioned doses of the sweetener, resulted in an activation of the membrane Na+, K+ -ATPase, as well as pure enzyme. Frontal cortex Mg2+-ATPase remained unaltered. Addition of l-cysteine (cys) or reduced glutathione (GSH) to ASP metabolites mixtures, corresponding to 150 or 200mg/kg doses of the sweetener, completely or partially restored to normal the modulated membrane and pure Na+, K+ -ATPase activities. CONCLUSION: CSF concentrations of the sum of ASP metabolites corresponding to the intake of common, abuse or toxic doses (34 or 150 or 200mg/kg, respectively) of the additive significantly increased rat frontal cortex Na+, K+ -ATPase and pure enzyme activities. Cys or GSH completely or partially restored to normal both enzyme activities, possibly due to amelioration of the cellular GSH reduction from the action of MeOH, a metabolite of the sweetener and/or by their scavenging effect.  相似文献   
118.
Valproic acid (VPA) and 8-hydroxy-2-deoxyguanosine (8-OHdG) are implicated with the free radicals production. We aimed to evaluate total oxidant status (TOS) and 8-OHdG in children on VPA monotherapy. Fifty patients with seizures, mean age 8.5+/-3.6 years, were divided into group A (N=26) and group B (N=24) with VPA serum levels 81.0+/-8.0 and 114+/-9.7 microg/mL, respectively. Thirty healthy children were the controls. Liver function tests and lipids were determined with routine methods, TOS and 8-OHdG with commercial kits, after 60 days on VPA therapy. Liver function parameters, lipids, TOS (647+/-43 micromol/L) and 8-OHdG (0.49+/-0.08 ng/mL) were significantly higher in group B than those in group A (580+/-40 micromol/L, 0.37+/-0.04 ng/mL, p<0.001) and controls (124+/-30 micromol/L, 0.11+/-0.04 ng/mL, p<0.001, respectively). Significant correlation coefficients were found between 8-OHdG versus TOS (r=0.67, p<0.001) and 8-OHdG versus VPA (r=0.60, p<0.001) levels. It is suggested that VPA impairs the liver function resulting in free radicals production. The latter seems to produce DNA oxidative damage in liver cells, not excluding neuronal cells, as evidenced by the measured remarkably increased 8-OHdG serum levels. 8-OHdG evaluation may be a useful biomarker to follow up the increased risk of degeneration process in VPA patients.  相似文献   
119.
Aspartame (ASP) consumption is suggested to be implicated with muscarinic dysfunction. The aim of this work was to evaluate the effect of ASP and its metabolites on acetylcholinesterase (AChE) activity in rat frontal cortex and pure enzyme. Rat frontal cortex homogenate or pure enzyme AChE (eel E. Electricus) were incubated with ASP and each of ASP components, phenylalanine (Phe), aspartic acid (asp), and methanol (MeOH) for 1 h at 37 °C. AChE was measured spectrophotometrically. The results showed that incubation of rat tissue or pure enzyme with the sum of ASP metabolites, as reported to be found in the CSF after 150 or 200 mg/kg ASP consumption, inhibited frontal cortex and pure AChE about −11% to −29% (p < 0.001). Asp, Phe or MeOH concentrations related to their CSF levels after ingestion of abuse or toxic ASP doses, when separately incubated with frontal cortex or pure AChE, resulted in a significant decrease of the enzyme activities. In conclusion:

ASP compounds may directly and/or indirectly act on the frontal cortex AChE. High or toxic doses of the sweetener remarkably decreased the enzyme activity. If this in vitro finding comes into human reality, it may be suggested that cholinergic symptoms are related to the consumption of the above ASP doses.  相似文献   

120.
Background: Two separate prescribing budget regimes (part of GP fundholding and the indicative prescribing scheme) were introduced into UK general practice in April 1991 in an attempt to contain the growth in NHS expenditure on prescribed drugs.Objectives: The aims of this study are (i) to examine whether the fundholding scheme has been more effective at containing prescribing cost growth than the indicative prescribing scheme and (ii) to ascertain whether its implementation, at a practice level, has been affected by local circumstances and conditions.Methods: Prescribing cost data were collected from two rural, English Family Health Services Authorities for the financial years 1990/1991 to 1993/1994. Exploratory analysis was performed using regression analysis and non-parametric statistical techniques.Results and conclusions: Initially, the fundholding scheme has been the more effective at containing expenditure on prescribed drugs. However, the implementation of the schemes in rural areas has probably been affected by the existence of practices with permission to dispense drugs to their own patients, due to a lack of pharmacies in such areas.  相似文献   
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