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71.
Conventional triple therapies for Helicobacter pylori (H. pylori ) eradication have recently shown a disappointing reduction in effectiveness in many countries. The main reason for failure was found to be bacterial resistance to one of the most commonly used antibiotics, clarithromycin. An additional problem for conventional triple therapy is the high rate of resistance to metronidazole found in Europe, America and Asia. In Italy, in the last 15 years a 2-fold increase in resistance has occurred. A recent study of the whole of Italy included about 20 patients from each region at the first endoscopic diagnosis of H. pylori infection. The most surprising result was the patchy distribution of resistance, which was almost absent in two regions (one northern and one southern), although the highest prevalence was found in some regions of the South. In the paediatricpopulation we found a 25% prevalence of resistance in a sample of H. pylori positive children observed between 2002 and 2007, mirroring data obtained in southern European countries. Clarithromycin resistance assessment is currently based on phenotypic detection performed after culture the agar dilution method or E-test, and genotypic methods based on polymerase chain reaction (PCR). In a recent comparative study we found a 71.2% agreement between the two methods. Culture-free techniques are highly accurate in finding even minimal traces of genotypically resistant strains. Moreover, PCR-based tools are accurate in detecting a heteroresistant status, defined as the co-existence of some strains that are susceptible and some resistant to the same antibiotic in an individual patient. Three point mutations, namely A2143G , A2142G and A2142C , are responsible for 90% of cases of primary clarithromycin resistance in H. pylori strains isolated in Western countries, although we previously demonstrated that the presence of the A2143G mutation, but not A2142G or A2142C , significantly lowered the H. pylori eradication rate. Treatment failure has considerable cost/benefit implications because of "waste" of National Health System and patient resources, in terms of drugs, further diagnostic tests and medical examination expenses. Therefore, in future it would be very useful to be able to test for clarithromycin resistance before starting conventional triple therapy. Hopefully, fast, effective noninvasive tests may soon be devised to determine this condition.  相似文献   
72.
This Italian multicenter retrospective study compared the drug survival and efficacy of different anti‐TNF agents in psoriasis (PsO) and psoriatic arthritis (PsA) patients. A database of PsO/PsA patients treated with adalimumab, etanercept, and infliximab from May 2013 to May 2014 was analyzed. PASI 75, 90, and 100 was calculated at each time point to evaluate efficacy. Drug survival rate and probability of maintaining PASI response were evaluated. The impact of dependent variables on probability of PASI 75 loss was evaluated by logistic regression. 1,235 patients were included, 577 with PsO and 658 with PsA. Highest survival rates were observed with adalimumab followed by etanercept and infliximab in PsO and PsA patients. The probability of maintaining PASI response was significantly higher for adalimumab followed by infliximab. For PsO patients, the odds of losing PASI 75 was higher in etanercept‐treated patients (OR: 8.1; 95% CI: 4.2–15.6, p < .001) or infliximab (OR: 6.6; 95% CI: 2.6–16.3, p < .001) vs. adalimumab. Likewise, for PsA patients the odds of losing PASI 75 was higher in etanercept‐treated patients (OR: 2.3; 95% CI: 1.4–3.8, p = .01) or infliximab (OR: 2.2; 95% CI: 1.1–4.1, p = .018) vs. adalimumab. Adalimumab could be the best therapeutic option over other anti‐TNF agents for the treatment of PsO and PsA patients.  相似文献   
73.
Adrenocortical carcinoma is a rare endocrine malignancy with an estimated worldwide incidence of 0.5 - 2 per million/year. This neoplasm is characterized by a high risk of recurrence and a dismal prognosis owing to unsatisfactory overall survival. Surgery represents the cornerstone of adrenocortical carcinoma therapy, which can be associated to radiotherapy and adjuvant mitotane administration. In advanced cases, different chemotherapy regimens are used, but their relative efficacy is still unknown until the results of clinical trials under way will be published. Novel drugs have been recently developed based on the discovery of molecular pathways that trigger development and evolution of these tumors. More efficient treatments are widely expected in the future from these new targeted therapies as a hope of cure for patients affected with this aggressive malignancy.  相似文献   
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To evaluate the effectiveness of a cytological screening to prevent invasive cervical cancer in the province of Trento, a northern Italian area where a population-based cancer registry is active. The history of Pap test was evaluated through a case-control study in 61 population-based invasive cervical cancer patients, incident during 1995-2000, and in 244 age-matched (between 25 and 75 years old) controls. Women who had at least one Pap test had a reduced risk of invasive carcinoma of 80% (odds ratio=0.20; 95% confidence intervals 0.10-0.40). The protection of a previous Pap test for both squamous cell carcinoma (odds ratio=0.23; 95% confidence intervals 0.09-0.58) and adenocarcinoma (odds ratio=0.24; 95% confidence intervals 0.07-0.78) was similar. The overall protective effect of the Pap test was not seen among younger women (<40 years). The protective effect of the Pap test seems to be stronger for shorter intervals. Our study confirms that Pap-test screening, particularly in middle-aged and older women, is an effective public health intervention with encouraging results also for the prevention of cervical adenocarcinoma.  相似文献   
77.
The critical role that ether-à-go-go-related gene (erg) K(+) channels play in mating in Caenorhabditis elegans, neuronal seizures in Drosophila and cardiac action potential repolarization in humans has been well documented. Three erg genes (erg1, erg2 and erg3) have been identified and characterized. A structurally diverse number of compounds block these channels, but do not display specificity among the different channel isoforms. In this review we describe the blocking properties of several peptides, purified from scorpion, sea anemone and spider venoms, which are selective for certain members of the ERG family of channels. These peptides do not behave as classical pore blockers and appear to modify the gating properties of the channel. Genomic studies predict the existence of many other novel peptides with the potential of being more selective for ERG channels than those discussed here.  相似文献   
78.
Sodium channel toxins from sea anemones are employed as tools for dissecting the biophysical properties of inactivation in voltage-gated sodium channels. Cangitoxin (CGTX) is a peptide containing 48 amino acid residues and was formerly purified from Bunodosoma cangicum. Nevertheless, previous works reporting the isolation procedures for such peptide from B. cangicum secretions are controversial and may lead to incorrect information. In this paper, we report a simple and rapid procedure, consisting of two chromatographic steps, in order to obtain a CGTX analog directly from sea anemone venom. We also report a substitution of N16D in this peptide sample and the co-elution of an inseparable minor isoform presenting the R14H substitution. Peptides are named as CGTX-II and CGTX-III, and their effects over Nav1.1 channels in patch clamp experiments are demonstrated.  相似文献   
79.
OBJECTIVES: To compare the efficacy of bicalutamide monotherapy to maximal androgen blockade in advanced prostatic cancer. PATIENTS AND METHODS: Previously untreated patients with histologically proven stage C or D (American Urological Association Staging System) disease were randomly allocated to either bicalutamide (B) or goserelin plus flutamide (G+F). After disease progression, patients treated with B were assigned to castration. The primary endpoint for this trial was overall survival. Prostate cancer-specific survival and progression were included among secondary endpoints. RESULTS: In total 108 patients received B and 112 received G+F. At a median follow-up time of 54 months (range 1-89), 151 patients progressed and 113 died. There was no significant difference in the duration of either progression-free or overall survival. Hazards of progression, death and cancer-specific death, corrected by disease stage, tumor grade and baseline PSA level, showed that patients initially assigned to B had a higher risk of progression but a comparable risk of death and cancer-specific death with the exception of patients with G3 tumors who had an increased risk of death). CONCLUSIONS: In patients with well or moderately well differentiated tumors, B monotherapy followed by castration may offer the same survival chance as maximal androgen deprivation. In those patients it thus represents a reasonable choice that can avoid the side effects of androgen deprivation for considerable periods of time.  相似文献   
80.
Cresol poisoning was suspected in agroup of cattle presented for slaughter at a federaly inspected plant in Illinois. Four cattle died shortly after being unloaded at the slaughter facility, while another animal died after being returned to the feedlot of origin in Iowa. The clinical signs in the affected cattle were lethargy, depression, ataxia, leg weakness, sternal recumbency, dehydration, and severe bloating. Metacresol (3-methyl phenol), commonly found in disinfectants used to clean and sanitize farm equipment and barns, was detected in rumen content from 4 necropsied animals ranging from 25.3 to 52.6 ppm. The exact source of exposure was not identified, but was probably accidental on the farm of origin or on the trailers used for animal transit to the slaughter plant.  相似文献   
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