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1.

Objective

To evaluate evidence on the association between CYP2D6 genotype and tamoxifen response through.

Design

Systematic review and meta-analysis of prospective, cross-sectional and case-control studies published to 2012. For each study, relative risks and 95% confidence intervals were extracted and pooled with a fixed and random effects model. Heterogeneity, publication bias, subgroup, and meta-regression analyses were performed.

Data Sources

PubMed (inception-2012) and EMBASE (inception-2012).

Eligibility Criteria for Selecting Studies

Criteria for inclusion were studies reporting breast cancer outcomes in patients treated with tamoxifen and genotyped for polymorphisms in the CYP2D6 gene.

Results

Twenty-five studies of 13,629 individuals were identified, of which 22 investigated the association of CYP2D6 genotype with outcomes in breast cancer women all receiving tamoxifen treatment (“treatment-only” design). Three randomized trials evaluated the effect of CYP2D6 genotype on tamoxifen response (“effect modification” design). In analysis of treatment-only studies, the relative risk (RR) of all-cause mortality (>307 events in 4,936 patients) for carriers of a CYP2D6 reduced function allele was 1.11 (95% confidence interval (CI): 0.94 to 1.31) compared to individuals with normal/increased function CYP2D6 alleles. When we investigated a composite outcome including all-cause mortality and surrogate endpoints for overall survival (>307 events in 6,721 patients), carriers of a CYP2D6 reduced function allele had a RR of 1.27 (95% CI: 1.11 to 1.45). From two randomized trials that permitted effect-modification analysis, one had only 154 patients and showed evidence of effect modification of tamoxifen by CYP2D6 genotype for distant recurrence but was directionally opposite to that predicted, whereas a larger trial of 2,537 patients failed to show evidence of effect modification for breast cancer-free interval (P values for interaction 0.02 and 0.44, respectively).

Conclusions

Based on these findings, there is insufficient evidence to recommend CYP2D6 genotyping to guide tamoxifen treatment.  相似文献   

2.

Background

Nyctanthes arbor-tristis (Harshringar, Night Jasmine) has been traditionally used in Ayurveda, Unani and other systems of medicine in India. The juice of its leaves has been used by various tribal populations of India in treatment of fevers resembling malaria.

Aim of the study

This work reports the antiplasmodial activity guided fractionation of Harshringar leaves extract.

Methodology

Crude ethanolic Harshringar leaves extract and its RPHPLC purified fractions were studied for antiplasmodial potency against 3D7 (CQ sensitive) and Dd2 (CQ resistant) strains of P.falciparum and subsequently subjected to bioassay guided fractionation using reverse phase chromatography to pursue the isolation of active fractions.

Principal Findings

Harshringar crude leaves extract and some of its RPHPLC purified fractions exhibited promising antiplasmodial potency against 3D7 and Dd2 strains of P.falciparum.

Conclusions

The present study has provided scientific validity to the traditional use of leaves extract of Harshringar against malaria leading to the conclusion that this plant holds promise with respect to antimalarial phytotherapy. This is the first scientific report of antiplasmodial activity of RPHPLC fractions of Harshringar leaves extract against P.falciparum strains.  相似文献   

3.

Background

Adjuvant radiotherapy (RTE) still has a fundamental role as a post-operative treatment of locally advanced soft tissues sarcomas of the extremities. Moreover the employment of combined modalities in locally advanced soft tissues sarcomas of the extremities allow to maximize the chance of local cure even in difficult presentation cases, and possibly improve survival, especially in high-risk disease patients. In patients with sarcomas of the extremities in which definitive surgery has not been radical (with positive or “close” margins) radiotherapy can improve the results in terms of Disease Free Survival (DFS) and, together with chemotherapy, of Overall Survival (OS). We recommend radiotherapy in case of deep tumor location, inadequate surgical margins and grade 3 tumour; for positive or “marginal (or close)” excision (that means inadequate surgery) or in selected patients with a bad prognosis, we believe that a multidisciplinary approach can be preferable.

Introduction

Adjuvant radiotherapy (RTE) still has a fundamental role as a post-operative treatment. In patients with sarcomas of the extremities in whom definitive surgery has been or not radical (positive or “close” margins), radiotherapy with chemotherapy can improve the results in terms of Disease Free Survival (DFS) and Overall Survival (OS), while RTE alone seems to improve local control.

Materials and methods

From 1/2000 to 12/2005 we treated 34 patients affected by locally advanced sarcomas of the upper or lower extremities with radiotherapy (doses ranging from 54 to 66 Gy) and chemotherapy in 18/34 with an adjuvant scheme that consisted in Epirubicine (120 mg/m2) plus Ifosfamide (7000–9000 mg/m2).

Results

Disease Free Survival (DFS) and the Overall Survival (OS) rates were 76% and 82%, respectively. Eighteen patients developed one or more long-term side effects. Most of these complications were mild: all patients experienced only erithema, edema, local sclerosis or moderate pain.

Conclusion

Radiotherapy has an important role as a post-operative treatment also when surgery was non-radical. It improves local control more in patients with high-grade sarcomas of the extremity with positive or close margins. It is still difficult to assess the role of adjuvant chemotherapy.  相似文献   

4.
5.

Objective

Clinical trial outcomes often involve an ordinal scale of subjective functional assessments but the optimal way to quantify results is not clear. In stroke, the most commonly used scale, the modified Rankin Score (mRS), a range of scores (“Shift”) is proposed as superior to dichotomization because of greater information transfer. The influence of known uncertainties in mRS assessment has not been quantified. We hypothesized that errors caused by uncertainties could be quantified by applying information theory. Using Shannon’s model, we quantified errors of the “Shift” compared to dichotomized outcomes using published distributions of mRS uncertainties and applied this model to clinical trials.

Methods

We identified 35 randomized stroke trials that met inclusion criteria. Each trial’s mRS distribution was multiplied with the noise distribution from published mRS inter-rater variability to generate an error percentage for “shift” and dichotomized cut-points. For the SAINT I neuroprotectant trial, considered positive by “shift” mRS while the larger follow-up SAINT II trial was negative, we recalculated sample size required if classification uncertainty was taken into account.

Results

Considering the full mRS range, error rate was 26.1%±5.31 (Mean±SD). Error rates were lower for all dichotomizations tested using cut-points (e.g. mRS 1; 6.8%±2.89; overall p<0.001). Taking errors into account, SAINT I would have required 24% more subjects than were randomized.

Conclusion

We show when uncertainty in assessments is considered, the lowest error rates are with dichotomization. While using the full range of mRS is conceptually appealing, a gain of information is counter-balanced by a decrease in reliability. The resultant errors need to be considered since sample size may otherwise be underestimated. In principle, we have outlined an approach to error estimation for any condition in which there are uncertainties in outcome assessment. We provide the user with programs to calculate and incorporate errors into sample size estimation.  相似文献   

6.

Background

Human induced pluripotent stem cells (IPSCs) have enormous potential in the development of cellular models of human disease and represent a potential source of autologous cells and tissues for therapeutic use. A question remains as to the biological age of IPSCs, in particular when isolated from older subjects. Studies of cloned animals indicate that somatic cells reprogrammed to pluripotency variably display telomere elongation, a common indicator of cell “rejuvenation.”

Methodology/Principal Findings

We examined telomere lengths in human skin fibroblasts isolated from younger and older subjects, fibroblasts converted to IPSCs, and IPSCs redifferentiated through teratoma formation and explant culture. In IPSCs analyzed at passage five (P5), telomeres were significantly elongated in 6/7 lines by >40% and approximated telomere lengths in human embryonic stem cells (hESCs). In cell lines derived from three IPSC-teratoma explants cultured to P5, two displayed telomeres shortened to lengths similar to input fibroblasts while the third line retained elongated telomeres.

Conclusions/Significance

While these results reveal some heterogeneity in the reprogramming process with respect to telomere length, human somatic cells reprogrammed to pluripotency generally displayed elongated telomeres that suggest that they will not age prematurely when isolated from subjects of essentially any age.  相似文献   

7.

Background

Despite the high prevalence and major public health ramifications, obstructive sleep apnea syndrome (OSAS) remains underdiagnosed. In many developed countries, because community pharmacists (CP) are easily accessible, they have been developing additional clinical services that integrate the services of and collaborate with other healthcare providers (general practitioners (GPs), nurses, etc.). Alternative strategies for primary care screening programs for OSAS involving the CP are discussed.

Objective

To estimate the quality of life, costs, and cost-effectiveness of three screening strategies among patients who are at risk of having moderate to severe OSAS in primary care.

Design

Markov decision model.

Data Sources

Published data.

Target Population

Hypothetical cohort of 50-year-old male patients with symptoms highly evocative of OSAS.

Time Horizon

The 5 years after initial evaluation for OSAS.

Perspective

Societal.

Interventions

Screening strategy with CP (CP-GP collaboration), screening strategy without CP (GP alone) and no screening.

Outcomes measures

Quality of life, survival and costs for each screening strategy.

Results of base-case analysis

Under almost all modeled conditions, the involvement of CPs in OSAS screening was cost effective. The maximal incremental cost for “screening strategy with CP” was about 455€ per QALY gained.

Results of sensitivity analysis

Our results were robust but primarily sensitive to the treatment costs by continuous positive airway pressure, and the costs of untreated OSAS. The probabilistic sensitivity analysis showed that the “screening strategy with CP” was dominant in 80% of cases. It was more effective and less costly in 47% of cases, and within the cost-effective range (maximum incremental cost effectiveness ratio at €6186.67/QALY) in 33% of cases.

Conclusions

CP involvement in OSAS screening is a cost-effective strategy. This proposal is consistent with the trend in Europe and the United States to extend the practices and responsibilities of the pharmacist in primary care.  相似文献   

8.

Background

The associations between nutritional biomarkers and measures of sleep quantity and quality remain unclear.

Methods

Cross-sectional data from the National Health and Nutrition Examination Surveys (NHANES) 2005–2006 were used. We selected 2,459 adults aged 20–85, with complete data on key variables. Five sleep measures were constructed as primary outcomes: (A) Sleep duration; (B) Sleep disorder; (C) Three factors obtained from factor analysis of 15 items and labeled as “Poor sleep-related daytime dysfunction” (Factor 1), “Sleepiness” (Factor 2) and “Sleep disturbance” (Factor 3). Main exposures were serum concentrations of key nutrients, namely retinol, retinyl esters, carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein+zeaxanthin, lycopene), folate, vitamin B-12, total homocysteine (tHcy), vitamin C, 25-hydroxyvitamin D (25(OH)D) and vitamin E. Main analyses consisted of multiple linear, logistic and multinomial logit models.

Results

Among key findings, independent inverse associations were found between serum vitamin B-12 and sleep duration, 25(OH)D and sleepiness (as well as insomnia), and between folate and sleep disturbance. Serum total carotenoids concentration was linked to higher odds of short sleep duration (i.e. 5–6 h per night) compared to normal sleep duration (7–8 h per night).

Conclusions

A few of the selected serum nutritional biomarkers were associated with sleep quantity and quality. Longitudinal studies are needed to ascertain temporality and assess putative causal relationships.  相似文献   

9.

Background

Antibodies are important in the control of blood stage Plasmodium falciparum infection. It is unclear which antibody responses are responsible for, or even associated with protection, partly due to confounding by heterogeneous exposure. Assessment of response to partially effective antimalarial therapy, which requires the host to assist in clearing parasites, offers an opportunity to measure protection independent of exposure.

Methods

A cohort of children aged 1–10 years in Kampala, Uganda were treated with amodiaquine+sulfadoxine-pyrimethamine for uncomplicated malaria. Serum samples from the time of malaria diagnosis and 14 days later were analyzed for total IgG to 8 P. falciparum antigens using a quantitative indirect ELISA. Associations between antibody levels and risk of treatment failure were estimated using Cox proportional hazard regression.

Results

Higher levels of antibodies to apical membrane antigen 1 (AMA-1), but to none of the other 7 antigens were significantly associated with protection against treatment failure (HR 0.57 per 10-fold increase in antibody level, CI 0.41–0.79, p = 0.001). Protection increased consistently across the entire range of antibody levels.

Conclusions

Measurement of antibody levels to AMA-1 at the time of malaria may offer a quantitative biomarker of blood stage immunity to P. falciparum, a tool which is currently lacking.  相似文献   

10.

Background

Graphical representation of data is one of the most easily comprehended forms of explanation. The current study describes a simple visualization tool which may allow greater understanding of medical and epidemiological data.

Method

We propose a simple tool for visualization of data, known as a “quilt plot”, that provides an alternative to presenting large volumes of data as frequency tables. Data from the Australian Needle and Syringe Program survey are used to illustrate “quilt plots”.

Conclusion

Visualization of large volumes of data using “quilt plots” enhances interpretation of medical and epidemiological data. Such intuitive presentations are particularly useful for the rapid assessment of problems in the data which cannot be readily identified by manual review. We recommend that, where possible, “quilt plots” be used along with traditional quantitative assessments of the data as an explanatory data analysis tool.  相似文献   

11.

Background

Plasmodium falciparum malaria remains a major cause of illness and death in sub-Saharan Africa. Young children bear the brunt of the disease and though older children and adults suffer relatively fewer clinical attacks, they remain susceptible to asymptomatic P. falciparum infection. A better understanding of the host factors associated with immunity to clinical malaria and the ability to sustain asymptomatic P. falciparum infection will aid the development of improved strategies for disease prevention.

Methods and Findings

Here we investigate whether full differential blood counts can predict susceptibility to clinical malaria among Kenyan children sampled at five annual cross-sectional surveys. We find that the ratio of monocytes to lymphocytes, measured in peripheral blood at the time of survey, directly correlates with risk of clinical malaria during follow-up. This association is evident among children with asymptomatic P. falciparum infection at the time the cell counts are measured (Hazard ratio (HR)  =  2.7 (95% CI 1.42, 5.01, P  =  0.002) but not in those without detectable parasitaemia (HR  =  1.0 (95% CI 0.74, 1.42, P  =  0.9).

Conclusions

We propose that the monocyte to lymphocyte ratio, which is easily derived from routine full differential blood counts, reflects an individual''s capacity to mount an effective immune response to P. falciparum infection.  相似文献   

12.

Introduction

Recent evidence suggests a link between constitutional telomere length (TL) and cancer risk. Previous studies have suggested that longer telomeres were associated with an increased risk of melanoma and larger size and number of nevi. The goal of this study was to examine whether TL modified the risk of melanoma in melanoma-prone families with and without CDKN2A germline mutations.

Materials and Methods

We measured TL in blood DNA in 119 cutaneous malignant melanoma (CMM) cases and 208 unaffected individuals. We also genotyped 13 tagging SNPs in TERT.

Results

We found that longer telomeres were associated with an increased risk of CMM (adjusted OR = 2.81, 95% CI = 1.02–7.72, P = 0.04). The association of longer TL with CMM risk was seen in CDKN2A- cases but not in CDKN2A+ cases. Among CMM cases, the presence of solar injury was associated with shorter telomeres (P = 0.002). One SNP in TERT, rs2735940, was significantly associated with TL (P = 0.002) after Bonferroni correction.

Discussion

Our findings suggest that TL regulation could be variable by CDKN2A mutation status, sun exposure, and pigmentation phenotype. Therefore, TL measurement alone may not be a good marker for predicting CMM risk.  相似文献   

13.

Background

Vitamin D deficiency is more prevalent among SLE patients than the general population. Over the past decade, many studies across the globe have been carried out to investigate the role of vitamin D in SLE from various clinical angles. Therefore, the aim of this systematic review is to summarise and evaluate the evidence from the published literature; focusing on the clinical significance of vitamin D in SLE.

Methods

The following databases were searched: MEDLINE, Scopus, Web of Knowledge and CINAHL, using the terms “lupus”, “systemic lupus erythematosus”, “SLE and “vitamin D”. We included only adult human studies published in the English language between 2000 and 2012.The reference lists of included studies were thoroughly reviewed in search for other relevant studies.

Results

A total of 22 studies met the selection criteria. The majority of the studies were observational (95.5%) and cross sectional (90.9%). Out of the 15 studies which looked into the association between vitamin D and SLE disease activity, 10 studies (including the 3 largest studies in this series) revealed a statistically significant inverse relationship. For disease damage, on the other hand, 5 out of 6 studies failed to demonstrate any association with vitamin D levels. Cardiovascular risk factors such as insulin resistance, hypertension and hypercholesterolaemia were related to vitamin D deficiency, according to 3 of the studies.

Conclusion

There is convincing evidence to support the association between vitamin D levels and SLE disease activity. There is paucity of data in other clinical aspects to make firm conclusions.  相似文献   

14.

Background

Replication-independent endogenous double-strand breaks (RIND-EDSBs) occur in both humans and yeast in the absence of inductive agents and DNA replication. In human cells, RIND-EDSBs are hypermethylated, preferentially retained in the heterochromatin and unbound by γ-H2AX. In single gene deletion yeast strains, the RIND-EDSB levels are altered; the number of RIND-EDSBs is higher in strains with deletions of histone deacetylase, endonucleases, topoisomerase, or DNA repair regulators, but lower in strains with deletions of the high-mobility group box proteins or Sir2. In summary, RIND-EDSBs are different from pathologic DSBs in terms of their causes and consequences. In this study, we identified the nucleotide sequences surrounding RIND-EDSBs and investigated the features of these sequences as well as their break locations.

Results

In recent work, we detected RIND-EDSBs using ligation mediated PCR. In this study, we sequenced RIND-EDSB PCR products of resting state Saccharomyces cerevisiae using next-generation sequencing to analyze RIND-EDSB sequences. We found that the break locations are scattered across a number of chromosomes. The number of breaks correlated with the size of the chromosomes. Most importantly, the break occurrences had sequence pattern specificity. Specifically, the majority of the breaks occurred immediately after the sequence “ACGT” (P = 2.2E-156). Because the “ACGT” sequence does not occur primarily in the yeast genome, this specificity of the “ACGT” sequence cannot be attributed to chance.

Conclusions

RIND-EDSBs occur non-randomly; that is, they are produced and retained by specific mechanisms. Because these particular mechanisms regulate their generation and they possess potentially specific functions, RIND-EDSBs could be epigenetic marks.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-750) contains supplementary material, which is available to authorized users.  相似文献   

15.
16.
17.

Background

‘Learning disabilities’ (LD) refer to a wide group of neurological disorders caused by deficits in the central nervous system which influence the individual''s ability to maintain-, process or convey information to others in an efficient way. A worldwide discussion about the definitions of LD continues while a conceptual framework for studying the diverse life outcomes of adults with LD is still missing.

Objective

The aim was to review the literature on the activity and participation of adults with LD based on the International Classification of Functioning, Disability and Health (ICF) concepts.

Methods

“PsychInfo”, “Eric” and “PubMed” were searched for relevant literature according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). After a three-stage process, 62 articles relevant for domains of activity and participation of adults with LD were included in the review.

Results

Thirty-two articles focused on the domain of major life areas of education, work and employment and twelve articles focused on the domain of learning and applying knowledge. Limitations in activity and participation of the population with LD in these domains are recognized and discussed. Eighteen additional articles demonstrated that adults with LD confront difficulties in various life domains (e.g., communication, interpersonal interactions, mobility, and domestic life), however literature concerning these domains is scarce.

Conclusions

The ICF can be useful for further exploration of activity and participation characteristics of adults with LD in various life domains. Such exploration is required in order to gain a wider perspective of their functional characteristics and daily needs.  相似文献   

18.

Background

Antibodies that impair Plasmodium falciparum merozoite invasion and intraerythrocytic development are one of several mechanisms that mediate naturally acquired immunity to malaria. Attempts to correlate anti-malaria antibodies with risk of infection and morbidity have yielded inconsistent results. Growth inhibition assays (GIA) offer a convenient method to quantify functional antibody activity against blood stage malaria.

Methods

A treatment-time-to-infection study was conducted over 12-weeks in a malaria holoendemic area of Kenya. Plasma collected from healthy individuals (98 children and 99 adults) before artemether-lumefantrine treatment was tested by GIA in three separate laboratories.

Results

Median GIA levels varied with P. falciparum line (D10, 8.8%; 3D7, 34.9%; FVO, 51.4% inhibition). The magnitude of growth inhibition decreased with age in all P. falciparum lines tested with the highest median levels among children <4 years compared to adults (e.g. 3D7, 45.4% vs. 30.0% respectively, p = 0.0003). Time-to-infection measured by weekly blood smears was significantly associated with level of GIA controlling for age. Upper quartile inhibition activity was associated with less risk of infection compared to individuals with lower levels (e.g. 3D7, hazard ratio = 1.535, 95% CI = 1.012–2.329; p = 0.0438). Various GIA methodologies had little effect on measured parasite growth inhibition.

Conclusion

Plasma antibody-mediated growth inhibition of blood stage P. falciparum decreases with age in residents of a malaria holoendemic area. Growth inhibition assay may be a useful surrogate of protection against infection when outcome is controlled for age.  相似文献   

19.
20.

Objective

To evaluate the effects of study participation per se at the beginning of a sleep extension trial between screening, randomization, and the run-in visit.

Design

Subjects were screened, returned for randomization (Comparison vs. Intervention) after 81 days (median), and attended run-in visit 121 days later.

Setting

Outpatient.

Patients

Obese (N = 125; M/F, 30/95; Blacks/Whites/Other, N = 73/44/8), mean weight 107.6±19.7 kg, <6.5 h sleep/night.

Intervention

Non-pharmacological sleep extension.

Measurements

Sleep duration (diaries and actigraphy watch), sleep quality (Pittsburgh Sleep Quality Index), daily sleepiness (Epworth Sleepiness Scale), fasting glucose, insulin and lipids.

Results

Prior to any intervention, marked improvements occurred between screening and randomization. Sleep duration increased (diaries: 357.4 ±51.2 vs. 388.1±48.6 min/night; mean±SD; P<0.001 screening vs. randomization; actigraphy: 344.3 ±41.9 vs. 358.6±48.2 min/night; P<0.001) sleep quality improved (9.1±3.2 vs. 8.2±3.0 PSQI score; P<0.001), sleepiness tended to improve (8.9±4.6 vs. 8.3±4.5 ESS score; P = 0.06), insulin resistance decreased (0.327±0.038 vs. 0.351±0.045; Quicki index; P<0.001), and lipids improved, except for HDL-C. Abnormal fasting glucose (25% vs. 11%; P = 0.007), and metabolic syndrome (42% vs. 29%; P = 0.007) both decreased. In absence of intervention, the earlier metabolic improvements disappeared at the run-in visit.

Limitations

Relatively small sample size.

Conclusions

Improvements in biochemical and behavioral parameters between screening and randomization changed the “true” study baseline, thereby potentially affecting outcome. While regression to the mean and placebo effect were considered, these findings are most consistent with the “Hawthorne effect”, according to which behavior measured in the setting of an experimental study changes in response to the attention received from study investigators. This is the first time that biochemical changes were documented with respect to the Hawthorne effect. The findings have implications for the design and conduct of clinical research.

Trial Registration

ClinicalTrials.gov NCT00261898.  相似文献   

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