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61.
The recognition of the role of Helicobacter pylori in gastric diseases has led to the widespread use of antibiotics in the eradication of this pathogen. The most advocated therapy, triple therapy, often includes clarithromycin. It is well known that clarithromycin resistance is one of the major causes of eradication failure. The development of a rapid noninvasive technique that could easily be performed on fecal samples and that could also provide information about the antibiotic resistance of this microorganism is therefore advisable. Previous findings have demonstrated that clarithromycin resistance is due to a single point mutation in the 23S rRNA. All the mutations described have been associated with specific restriction sites, namely BsaI (A2143G), MboII (A2142C/G), and HhaI (T2717C). On this basis we have developed a new method, a seminested PCR, allowing screening for clarithromycin resistance of H. pylori directly on stool samples. This method furnished a 783-bp fragment of the 23S rRNA, which was subsequently digested by MboII, BsaI, and HhaI, in order to identify single point mutations associated with clarithromycin resistance. Of a total of 283 stool samples examined, 125 were H. pylori positive and two of them were shown to contain clarithromycin-resistant strains due to the presence of a mutation at position 2717, whereas no PCR products contained mutations at position 2142 or 2143. In order to evaluate the reliability of the new system, we compared the results of restriction analysis of the PCR products with the MICs shown by the H. pylori isolates by culturing gastric biopsies from the same patients.  相似文献   
62.
Background: Chronic obstructive pulmonary disease (COPD) patients have an increased cardiovascular (CV) morbidity and mortality. Common carotid intima-media thickness (CCA-IMT) and carotid plaques are surrogate markers of subclinical atherosclerosis and predictors of CV events.

Methods and results: We performed a meta-analysis to evaluate the association between COPD and subclinical atherosclerosis. Studies evaluating the impact of COPD on CCA-IMT and on the prevalence of carotid plaques were systematically searched.

Results: Twenty studies (2082 COPD patients and 4844 controls) were included, 12 studies with data on CCA-IMT (13 data-sets on 1180 COPD patients and 2312 controls) and 12 studies reporting on the prevalence of carotid plaques (1231 COPD patients and 4222 controls). Compared to controls, COPD patients showed a significantly higher CCA-IMT (mean difference [MD]: 0.201?mm; 95%CI: 0.142, 0.260; p?p?Conclusions: COPD is significantly associated with subclinical atherosclerosis. These findings may be useful to plan adequate CV prevention strategies.
  • Key messages
  • COPD patients show a higher CCA-IMT and an increased prevalence of carotid plaques compared with controls.

  • A more severe pulmonary disease is associated with a higher prevalence of carotid plaques in COPD patients.

  • Screening for subclinical atherosclerosis may be worthy in COPD patients to plan specific prevention strategies.

  相似文献   
63.

Background

Reversibility of advanced fibrosis after HCV-clearance is an important goal of therapy.

Objectives

Measuring liver stiffness (LS) by transient elastography (TE) might be helpful in this setting.

Patients and Methods

We evaluated 104 patients with biopsy-proven chronic hepatitis C (CHC) and sustained virological response (SVR) after Peg-Interferon (IFN) plus ribavirin since at least 18 months. HCV-eradication was confirmed searching for serum HCV-RNA (TMA® sensitivity > 5-10 IU/ml). Data from literature reported the best LS cut-off values for different stages of liver fibrosis were 7.1 kPa for Metavir stage 2 (F2), 9.5 kPa for F3 and 12.5 for cirrhosis (F4).

Results

TE was not reliable in four SVR obese patients. Metavir-stage of biopsy was F0-1 in 28, F2 in 47, F3 in 17 and F4 in eight patients. The median interval elapsed since achieving SVR was 36 months (range: 18-77, SD¬¬:18). Stratifying patients according to the histological stage assessed before treatment, a clear-cut gradient of LS values was observed from F0-1: median: 3.8 kPa (range: 3.5-4.9) to F2: 4.6 kPa (3.8-6.0), F3: 6.2 kPa (4.8-8.6) and F4: 8.4 kPa (6.2-9.2) (P = 0.001). Overall, 86 patients had lower values of LS than the expected LS values according to Metavir-stage. At multivariate logistic analysis γ-GT and histological steatosis were independently associated with persistence of higher values of LS.

Conclusion

Long term responders to IFN-based therapies have lower LS values than those who are untreated and still viraemic. High levels of γ-GT and liver steatosis, all markers of insulin resistance, may hamper reduction of liver stiffness after HCV-clearance.  相似文献   
64.
BackgroundSex-based differences in the association between C-reactive protein (CRP) and cardiovascular events in patients with coronary artery disease (CAD) are incompletely investigated. We investigated whether there are gender differences in the association between CRP and outcome in patients with CAD after percutaneous coronary intervention (PCI).MethodsThis study included 13,170 consecutive patients with CAD: 10,098 men and 3072 women. CRP was measured on admission in all patients. The primary outcome was 1-year mortality.ResultsCRP level (median [25th–75th percentiles]) was higher in women than in men (3.08 [1.30–8.37] mg/L vs 2.30 [0.92–6.47] mg/L; P < 0.001). CRP was > 3 mg/L in 4250 men (42.1%) and 1554 women (50.6%; P < 0.001). One-year mortality was 4.9% (n = 641 deaths). Deaths occurred in 318 men with CRP > 3 mg/L and 122 men with CRP ≤ 3 mg/L (mortality estimates 7.7% and 2.1%, P < 0.001) and in 154 women with CRP > 3 mg/L and 47 women with CRP ≤ 3 mg/L (mortality estimates 10.1% and 3.2%, P < 0.001). After adjustment in the Cox model, CRP was associated with increased risk of mortality in women (adjusted hazard ratio [HR] = 1.03, 95% confidence interval [CI] 1.01–1.04, P < 0.001 for each 5 mg/L increase) and in men (adjusted HR = 1.02 [1.01–1.03], P < 0.001, for each 5 mg/L increase). CRP predicted mortality with an area under the receiver-operating characteristic curve = 0.721, [0.683–0.760] in women and 0.732, [0.707–0.757] in men (P = 0.659).ConclusionsElevated CRP levels provide similar prognostic information in men and women with CAD after PCI which is independent and supplementary to that provided by conventional cardiovascular risk factors.  相似文献   
65.
We developed a multiplex polymerase chain reaction (M-PCR) assay to simultaneously detect Trichomonas vaginalis, Mycoplasma hominis, and Ureaplasma urealyticum. The test is extremely specific and has a sensitivity of 10 cells for T. vaginalis and U. urealyticum and of 1 cell for M. hominis. The technique was validated on vaginal swabs from 240 women presenting symptoms of vaginitis, and results were compared with data obtained using microscopic and culture techniques on the same patients. The M-PCR revealed to be greatly more sensitive and specific than traditional techniques. It has been well demonstrated, in vitro, that T. vaginalis can establish a symbiosis with M. hominis; our data confirm in vivo this strict association: in fact, M. hominis has been detected in 78.6% of all samples positive for T. vaginalis, as compared to only 4.8% of women without trichomoniasis. The species specificity of this association has been confirmed by the absence of any significant correlation between T. vaginalis and U. urealyticum.  相似文献   
66.
OBJECTIVE: To evaluate the effect of prostaglandin E2 (PGE2) and interleukin-1beta (IL-1beta) on integrin expression. DESIGN Cultures of endometrial epithelial cells from normal endometrium. SETTING: All endometrial specimens were obtained from the Obstetrics and gynecology Department of the Catholic University, Rome, Italy. PATIENTS: Four patients were normal menstrual cycles undergoing operative laparoscopy for non-endometrial problems. INTERVENTION: Endometrial samples were collected by uterine courettings. MAIN OUTCOME MEASURE: Immunocytochemistry for beta1 and beta3 integrin subunits. RESULTS: PGE2 clearly enhances both beta1 and beta3 integrin subunit expression. IL-1beta seem to slightly increase only beta3 subunit expression. CONCLUSIONS: In light of the critical role played by eicosanoids in endometrial differentiation, we suggest that PGE2 is also involved in local paracrine regulation of integrin expression.  相似文献   
67.
BACKGROUND: The aim of this prospective study was to evaluate the effects of the new monophasic oral contraceptives on the audiological system in premenopausal women. METHODS: The auditory brainstem response (ABR) was measured in 94 women during the follicular, periovular and luteal phases of one menstrual cycle in which ovulation was confirmed using sonography and serum progesterone concentration. The latencies for waves I, III and V were determined, and the inter-peak intervals were calculated for waves I-III, I-V and III-V. All 94 women began taking oral contraceptives: 23 women used 20 microg ethinyl estradiol (EE) plus 150 microg desogestrel, 24 women used 30 microg EE plus 75 microg gestodene, and 47 women used 15 microg EE plus 60 microg gestodene. During the third month of contraceptive intake, each subject was again tested for ABR, as above. RESULTS: The wave latencies and inter-peak intervals showed shorter values during the periovular phase with respect to the luteal phase (P < 0.05), the follicular phase for wave I and for inter-peak interval I-V (P < 0.05) of the menstrual cycle. All of the ABR results in pill users were statistically different from those of the periovular phase (P < 0.05), though similar to those of both the luteal and follicular phases (P = NS). CONCLUSIONS: ABR seems to depend on the variations of ovarian steroids during the menstrual cycle and during oral contraceptive intake.  相似文献   
68.
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70.
Photobiological research in the last 30 yr has shown the existence of ultraweak photon emission in biological tissue, which can be detected with sophisticated photomultiplier systems. Although the emission of this ultraweak radiation, often termed biophotons, is extremely low in mammalian cells, it can be efficiently increased by ultraviolet light. Most recently it was shown that UV-A (330 to 380 nm) releases such very weak cell radiation in differentiated human skin fibroblasts. Based on these findings, a new and powerful tool in the form of UV-A-laser-induced biophotonic emission of cultured cells was developed with the intention to detect biophysical changes between carcinogenic and normal cells. With suspension densities ranging from 1 to 8 x 10(6) cells/mL, it was evident that an increase of the UV-A-laser-light induced photon emission intensity could be observed in normal as well as melanoma cells. Using this new detection procedure of ultraweak light emission, photons in cell suspensions as low as 100 microL could be determined, which is a factor of 100 lower compared to previous procedures. Moreover, the detection procedure has been further refined by turning off the photomultiplier system electronically during irradiation leading to the first measurements of induced light emission in the cells after less than 10 micros instead of 150 ms, as reported in previous procedures. This improvement leads to measurements of light bursts up 10(7) photons/s instead of several hundred as found with classical designs. Overall, we find decreasing induction ratings between normal and melanoma cells as well as cancer-prone and melanoma cells. Therefore, it turns out that this highly sensitive and noninvasive device enables us to detect high levels of ultraweak photon emission following UV-A-laser-induced light stimulation within the cells, which enables future development of new biophysical strategies in cell research.  相似文献   
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