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971.
Epigenetic modifications include DNA methylation, his-tone modifications, and micro RNA. Gene alterations have been found to be associated with cardiovascular diseases, and epigenetic mechanisms are continuously being studied to find new useful strategies for the clinical management of afflicted patients. Numerous cardiovascular disorders are characterized by the abnormal methylation of Cp G islands and so specific drugs that could inhibit DNA methyltransferase directly or by reducing its gene expression(e.g., hydralazine and procainamide) are currently under investigation. The anti-proliferative and anti-inflammatory properties of histone deacetylase inhibitors and their cardio-protective effects have been confirmed in preclinical studies. Furthermore, the regulation of the expression of micro RNA targets through pharmacological tools is still under development. Indeed, large controlled trials are required to establish whether current possible candidate antisense micro RNAs could offer better therapeutic benefits in clinical practice. Here, we updated therapeutic properties, side effects, and feasibility of eme-rging epigenetic-based strategies in cardiovascular diseases by highlighting specific problematic issues that still affect the development of large scale novel therapeutic protocols.  相似文献   
972.
Introduction: There has been a striking increase in the emergence of multidrug-resistant pathogens in recent times. Delafloxacin is a novel, broad-spectrum fluoroquinolone with antimicrobial activity against resistant Gram-positive, Gram-negative and anaerobic organisms. It has the potential to treat a variety of infections including complicated skin and skin structure infections and respiratory tract infections.

Areas covered: In this review, the authors report the microbiological spectrum of activity of delafloxacin as well as its pharmacokinetic characteristics. They also report the results of recent studies investigating its safety and efficacy.

Expert opinion: The profile of delafloxacin offers several advantages. Delafloxacin presents a broad spectrum of activity against pathogens involved in respiratory infections and complicated skin and skin structure infections (SSSIs), including methicillin-resistant Staphylococcus aureus. It has also shown activity against Gram-negative pathogens, such as quinolone-susceptible and -resistant strains of Escherichia coli and Klebsiella pneumoniae and quinolone-susceptible Pseudomonas aeruginosa. The availability of an oral formulation supports its use in sequential therapy. The efficacy and tolerability of delafloxacin have been demonstrated in Phase II clinical trials in comparison with moxifloxacin for respiratory infections and linezolid and vancomycin in SSSIs. Compared with other quinolones such as moxifloxacin, delafloxacin showed comparable efficacy and a lower rate of adverse effects. The results of new Phase III studies are awaited to confirm delafloxacin’s future applications in the treatment of SSSIs.  相似文献   

973.
Primary dysmenorrhoea is the most frequent gynaecological condition, with a prevalence of 40 - 90% in women within the reproductive age. It is characterised by cyclic pelvic pain related to menstrual period, vomiting and headache. As prostaglandins and leukotrienes appear to be a major causative factor in this condition, NSAIDs are the first choice for treatment. Acetaminophen is an over-the-counter analgesic/antipyretic agent widely used in primary dysmenorrhoea as monotherapy or in combination. It has a weak inhibitory action on peripheral prostaglandin synthesis. Acetaminophen displays good gastrointestinal tolerance without any effect on haemostasis. Its combination with pamabrom, a mild diuretic agent, (Women s Tylenol Menstrual Relief Caplets, Midol Teen) was approved by the FDA for use in this indication. Nevertheless, the available information concerning the efficacy of acetaminophen in primary dysmenorrhoea is limited and not conclusive with respect to other NSAIDs or even placebo. The clinical evidence regarding the association with pamabrom is even more scarce. Well-designed, randomised, controlled trials are required to demonstrate the efficacy of the combination of acetaminophen plus pamabrom in the treatment of primary dysmenorrhoea.  相似文献   
974.
BACKGROUND: Adverse drug reactions (ADRs) are common causes of in-hospital complications for elderly people. The purpose of the present study is to verify whether concealed renal insufficiency, that is, reduction of the estimated glomerular filtration rate (GFR) in people with normal serum creatinine levels, is a risk factor for ADRs in elderly hospitalized patients. METHODS: We used data on 11,687 hospitalized patients enrolled in the Gruppo Italiano di Farmacovigilanza nell'Anziano study. The outcomes of the study were any ADR, ADR to hydrosoluble drugs, and ADR to any other drug during the hospital stay. We compared 3 groups: normal renal function (normal serum creatinine levels and normal estimated GFRs), concealed (normal serum creatinine levels and reduced estimated GFRs), or overt (increased creatinine levels and reduced estimated GFRs) renal insufficiency. The relationship between renal function and ADR was evaluated using contingency tables and multiple regression analysis including potential confounders. RESULTS: Concealed renal insufficiency was detected in 1631 (13.9%) patients and was frequently associated with male sex and poor nutritional status. Hydrosoluble drugs were responsible for 301 of the 941 recorded ADRs. After adjusting for potential confounders, both concealed (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.15-1.25) and overt (OR, 2.02; 95% CI, 1.54-2.65) renal failure were associated with ADR to hydrosoluble drugs, but not with ADR to other drugs (OR, 0.83 [95% CI, 0.65-1.08], and OR, 1.01 [95%CI, 0.83-1.23], respectively). CONCLUSION: Older hospitalized patients frequently have impaired renal function despite normal serum creatinine levels and are exposed to an increased risk of ADRs to hydrosoluble drugs.  相似文献   
975.
In this study, the Gαqi5 protein was used to force the human nociceptin/orphanin FQ (N/OFQ) peptide (NOP) receptor to signal through the Ca2+ pathway in CHO cells. [Ca2+]i levels were monitored using the fluorometer FlexStation II and the Ca2+ dye Fluo 4 AM. Concentration response curves were generated with a panel of full and partial agonists, while NOP antagonists were assessed in inhibition-response curves. The following rank order of potency of antagonists was measured: naloxone, which is superimposable to literature findings. The rank order of potency of full and partial agonists is also similar to that obtained in previous studies with the exception of a panel of ligands (UFP-112, Ro 64-6198, ZP120, UFP-113) whose potency was relatively low in the Gαqi5–NOP receptor calcium assay. Interestingly, these NOP ligands are characterized by slow kinetic of interaction with the NOP receptor, as demonstrated by bioassay experiments. These results demonstrated that the FlexStation II–Gαqi5–NOP receptor calcium assay represents an adequate and useful screening for NOP receptor ligands, particularly for antagonists.  相似文献   
976.
Background::Soft tissue sarcoma (STS) is a heterogeneous group of rare neoplasms whose aetiology is largely unknown. Dioxin and dioxin-like compounds, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and polychlorinated biphenyls (PCBs), are potential risk factors for STS.Objectives:To investigate the relation of 17 PCBs congeners, assessed in human plasma, with STS risk.Methods:We conducted a case-control study in Italy, including 52 STS cases and 99 hospital-based controls. Selected PCB were extracted by high-performance liquid chromatography (HPLC) and measured with gas chromatography-mass spectrometry (GC-MS). Odds ratios (OR), and the corresponding 95% confidence intervals (CI), were estimated through multivariate logistic regression models.Results:The most frequently detected PCB congeners were 138, 170, 180 and 149 (detected in 40-77% of controls). The OR for the sum of all 17 PCB congeners was 1.20 (95% CI 0.50-2.92). In categorical analysis no consistent association was found for individual congeners and for groups based on Wolff’s classification or the degree of chlorination. For continuous estimates, borderline positive associations emerged for Wolff’s groups 2A (OR 1.23, 95% CI 0.97-1.55), 2B (OR 1.34, 95% CI 1.00-1.77, and 3 (OR 1.19, 95% CI 0.96-1.49), for moderately (OR 1.20, 95% CI 0.96-1.51) and highly (OR 1.18, 95% CI 0.99-1.41) chlorinated PCBs, and for congeners 170 (OR 1.26, 95% CI 0.98-1.63), 180 (OR 1.26, 95% CI 0.97-1.64) and 138 (OR 1.45, 95% CI 1.02-2.04).Discussion:Most associations between PCBs and STS risk were not significant, but, given the limited sample size, we cannot exclude moderate associations.Key words: Soft tissue sarcoma, polychlorinated biphenyls, epidemiology, environmental risk factors, chemical contaminants, case-control study  相似文献   
977.

Background

The contraceptive efficacy of emergency contraceptive pills containing levonorgestrel (LNG-EC) has been estimated in most previous studies by judging the day of ovulation from presumptive menstrual cycle data, thus providing poorly reliable estimates.

Methods

In the present study, the efficacy of LNG-EC was determined in 393 cycles by dating ovulation on the basis of reliable hormonal and ovarian parameters validated by a database constructed in a separate study. In addition, the efficacy was determined separately for cycles in which LNG-EC was given before or after ovulation.

Results

For the 148 women who had sexual intercourse during the fertile days, the overall accumulated probability of pregnancy was 24.7, while altogether 8 pregnancies were observed. Thus, the overall contraceptive efficacy of LNG-EC was 68%. Among the 103 women who took LNG-EC before ovulation (days −5 to −1), 16 pregnancies were expected and no pregnancy occurred (p<.0001). Among the 45 women who took LNG-EC on the day of ovulation (day 0) or thereafter, 8 pregnancies occurred and 8.7 were expected (p=1.00). These findings are incompatible with the inhibition of implantation by LNG-EC in women. The same cases were also analyzed using the presumptive menstrual cycle data, and important discrepancies were detected between the two methods.

Conclusion

The efficacy of LNG-EC has been overestimated in studies using presumptive menstrual cycle data. Our results confirm previous similar studies and demonstrate that LNG-EC does not prevent embryo implantation and therefore cannot be labeled as abortifacient.  相似文献   
978.
PURPOSE: To investigate the relationship between rectal bleeding and dosimetric-clinical parameters in patients receiving three-dimensional conformal radiotherapy (3D-CRT) for localized prostate cancer. METHODS: In a retrospective national study (AIROPROS01-01, AIRO: Associazione Italiana Radioterapia Oncologica), planning/clinical data for 245 consecutive patients with stage T1-4N0-x prostate carcinoma who underwent 3D-CRT to 70-78 Gy (ICRU point) were pooled from four Italian institutions. The correlation between late rectal bleeding and rectal dose-volume data (the percentage of rectum receiving more than 50, 55, 60, 65, 70, and 75 Gy [V(50-70)]) and other dosimetric and clinical parameters were investigated in univariate (log-rank) and multivariate (Cox regression model) analyses. Median follow-up was 2 years. RESULTS: Twenty-three patients were scored as late bleeders according to a modified RTOG definition (Grade 2: 16; Grade 3: 7); the actuarial 2-year rate was 9.2%. Excepting V75, all median and third quartile V(50-70) values were found to be significantly correlated with late bleeding at univariate analysis. The smallest p value was seen for V(50) below/above the third quartile value (66%). The V70 (cut-off value: 30%) was found to be also predictive for late bleeding. In the high-dose subgroup (74-78 Gy), Grade 3 bleeding was highly correlated with this constraint. The predictive value of both V(50) and V(70) was confirmed by multivariate analyses. CONCLUSIONS: The present article provides evidence for correlation between rectal DVH parameters and late rectal bleeding in patients treated with curative intent with 3D-CRT. To keep the rate of moderate/severe rectal bleeding below 5-10%, it seems advisable to limit V(50) to 60-65%, V(60) to 45-50%, and V70 to 25-30%.  相似文献   
979.
The neuropeptide substance P is a transmitter candidate for certain primary afferent fibers which terminate in the substantia gelatinosa. In this study the light and electron microscopic localization of substance P in the substantia gelatinosa of the spinal trigeminal nucleus of the rat has been studied using immunocytochemical procedures. Substance P immunoreactive fibers were observed mainly in lamina I and outer lamina II. Ultrastructural analysis revealed immunoreactivity in unmyelinated fibers and in axon terminals which contained agranular spherical vesicles and large dense-cored vesicles and which made predominantly simple asymmetric axodendritic synaptic contacts. Immunoreactive terminals only rarely formed the central terminal of synaptic glomeruli and in only one example was a stained terminal possibly postsynaptic to an unstained terminal. The majority of synapses were onto small dendrites in outer lamina II and in some cases these dendrites were themselves presynaptic to other dendrites. Immunoreactive terminals also synapsed with the soma and proximal dendrites of large neurons on the border of laminae I and II. The results show that there are at least two distinct targets for substance P immunoreactive terminals in the substantia gelatinosa, namely the large lamina I neurons and lamina II probable intemeurons. Some of the former may be projection neurons while some of the latter may correspond to the inhibitory islet cells described by Gobel and colleagues in the cat. In addition the results indicate that few substance P immunoreactive terminals receive axoaxonic synapses and emphasize instead the role of postsynaptic interactions. In particular the results suggest several sites at which substance P might interact postsynaptically with the neuropeptide enkephalin.  相似文献   
980.
Digestive Diseases and Sciences - Esophageal diverticula can cause significant symptoms and affect the quality of life. There has been recent interest in the use of peroral endoscopic myotomy in...  相似文献   
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