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101.
102.
One of the classical and traditional wall typology built in agricultural or pastoral landscapes are dry stone walls (walls built only of stones without concrete). These vertical surfaces are expected to increase habitat heterogeneity and to play an important role for biodiversity. This study focused on two groups of organisms: amphibians, represented by the rock-dwelling salamander Hydromantes strinatii, that are expected to use walls mainly as shelters, and molluscs, which use of walls may be affected mainly by the trophic resources available. A mountain area of the northern Appennines (NW-Italy) was surveyed to assess the differences between dry stone walls and the wall typologies in terms of morphology, surrounding landscape and salamander and mollusc occurrence; the relationships between wall typology features and salamander and mollusc distribution were assessed. Dry stone walls were more heterogeneous than concrete walls and hosted more lichens than natural rocky walls. They were more used by H. strinatii juveniles than the other walls and played an important role for their distribution. They were positively related to the occurrence of several molluscan species, including species with high ecological plasticity and rock-dwelling species. Among wall features, the most important for molluscs species distribution was vegetation cover, followed by lichen cover and heterogeneity, confirming the importance of trophic content for mollusc exploitation, while vegetated without concrete walls hosted higher number of species. The results suggest that dry stone walls can be important for fauna biodiversity and should be maintained and preserved as a part of landscape management.  相似文献   
103.
Immunotherapy encourages the recipient’s own immune response to destroy cancer cells, and current evidence suggests that immunotherapies may be most beneficial in early metastatic castration-resistant prostate cancer (mCRPC). Sipuleucel-T is the first therapeutic cancer vaccine to be approved by both the US Food and Drug Administration and European Medicines Agency for the treatment of asymptomatic or minimally symptomatic mCRPC. Combining immunotherapy with other treatments may have potent anticancer effects; cytoreductive therapies can release tumor antigens and promote a proinflammatory environment that could augment immunotherapies. However, some cytoreductive agents or coadministered drugs may be immunosuppressive. Understanding these interactions between different mCRPC treatment modalities may offer further potential to improve patient outcomes.Key words: Combination therapy, Prostate cancer, Sipuleucel-TImmunotherapy has emerged as a powerful tool against prostate cancer, in addition to surgery, radiotherapy, hormone therapy, and chemotherapy. For 30 years, investigators tried to rebalance the compromised immune system in patients with urologic cancers using a number of different agents.1,2 In April 2010, the autologous cellular immunotherapy sipuleucel-T became the first therapeutic cancer vaccine to be approved by the US Food and Drug Administration (FDA).3 This therapy targets the prostatic acid phosphatase (PAP) and has been indicated for the treatment of asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC), based on results from three randomized, controlled, phase 3 studies.36 Recently, sipuleucel-T was also approved by the European Medicines Agency (EMA) for the treatment of asymptomatic or minimally symptomatic mCRPC in men in whom chemotherapy is not yet clinically indicated.7Although this immunotherapy has been shown to extend overall survival (OS),5 sequencing or combining immunotherapy with other treatments for mCRPC has the potential to further improve outcomes.8,9 However, before immunotherapy-based combination regimens can be integrated into clinical practice, it is critical to have a better understanding of the interactions between these different modalities.  相似文献   
104.

Objective

To assess the performance of QuantiFERON-TB Gold In-Tube (QFT-GIT) test for active tuberculosis (TB) in HIV adults, and its variation over time in patients on antiretroviral therapy (ART) and/or isoniazide preventive therapy (IPT).

Methods

Transversal study and cohort nested in the Temprano ANRS 12136 randomized controlled trial assessing benefits of initiating ART earlier than currently recommended by World Health Organization, with or without a 6-month IPT. Performance of QFT-GIT for detecting active TB at baseline in the first 50% participants, and 12-month incidence of conversion/reversion in the first 25% participants were assessed. QFT-GIT threshold for positivity was 0.35 IU/ml.

Results

Among the 975 first participants (median baseline CD4 count 383/mm3, positive QFT-GIT test 35%), 2.7% had active TB at baseline. QFT-GIT sensitivity, specificity, positive and negative predictive value for active TB were 88.0%, 66.6%, 6.5% and 99.5%. For the 444 patients with a second test at 12 months, rates for conversion and reversion were 9.3% and 14%. Reversion was more frequent in patients without ART and younger patients. IPT and early ART were not associated with reversion/conversion.

Conclusion

A negative QFT-GIT could rule out active TB in HIV-infected adults not severely immunosuppressed, thus avoiding repeated TB testing and accelerating diagnosis and care for other diseases.

Trial Registration

ClinicalTrials.gov NCT00495651.  相似文献   
105.
Olympic-style lifts (OSL) and plyometric exercises (PE) are frequently combined with traditional resistance training (TRT) to improve athletic performance. The goal of this study was to directly compare the performance effect of TRT (30 minutes) combined with either OSL or nondepth-jump PE (15 minutes) on entry level competitive collegiate athletes. Ten female and 5 male competitive soccer players, divided into 2 groups, completed 12 weeks of tri-weekly training during their off-season. Countermovement vertical jump, 4 repetition maximum squat, 25-m sprint, and figure-8 drill on a 5-dot mat were conducted pre-, mid-, and postintervention. Significant improvements were made by both groups in each performance parameter over the 12-week period (p < 0.05), with no significant differences found between the training groups. Although these training modalities may achieve their results through slightly different mechanisms, the performance-related improvements may not be significantly different for entry-level collegiate athletes with little resistance training experience.  相似文献   
106.
Oxidative respiration is strongly temperature driven. However, in woody stems, efflux of CO2 to the atmosphere (E A), commonly used to estimate the rate of respiration (R S), and stem temperature (T st) have often been poorly correlated, which we hypothesized was due to transport of respired CO2 in xylem sap, especially under high rates of sap flow (f s). To test this, we measured E A, T st, f s and xylem sap CO2 concentrations ([CO2*]) in 3-year-old Populus deltoides trees under different weather conditions (sunny and rainy days) in autumn. We also calculated R S by mass balance as the sum of both outward and internal CO2 fluxes and hypothesized that R S would correlate better with T st than E A. We found that E A sometimes correlated well with T st, but not on sunny mornings and afternoons or on rainy days. When the temperature effect on E A was accounted for, a clear positive relationship between E A and xylem [CO2*] was found. [CO2*] varied diurnally and increased substantially at night and during periods of rain. Changes in [CO2*] were related to changes in f s but not T st. We conclude that changes in both respiration and internal CO2 transport altered E A. The dominant component flux of R S was E A. However, on a 24-h basis, the internal transport flux represented 9–18% and 3–7% of R S on sunny and rainy days, respectively, indicating that the contribution of stem respiration to forest C balance may be larger than previously estimated based on E A measurements. Unexpectedly, the relationship between R S and T st was sometimes weak in two of the three trees. We conclude that in addition to temperature, other factors such as water deficits or substrate availability exert control on the rate of stem respiration so that simple temperature functions are not sufficient to predict stem respiration.  相似文献   
107.

Background

Detecting paroxysmal atrial fibrillation (PAF) in patients with cerebral ischemia is challenging. Frequent premature atrial complexes (PAC/h) and the longest supraventricular run on 24-h-Holter (SV-run24 h), summarised as excessive supraventricular ectopic activity (ESVEA), may help selecting patients for extended ECG-monitoring, especially in combination with echocardiographic marker LAVI/a’ (left atrial volume index/late diastolic tissue Doppler velocity).

Methods

Retrospective analysis from the prospective monocentric observational trial Find-AF (ISRCTN-46104198). Patients with acute stroke or TIA were enrolled at the University Hospital Göttingen, Germany. Those with sinus rhythm at presentation received 7-day Holter-monitoring. ESVEA was quantified in one 24-hour interval free from PAF. Echocardiographic parameters were assessed prospectively.

Results

PAF was detected in 23/208 patients (11.1%). The median was 4 [IQR 1; 22] for PAC/h and 5 [IQR 0; 9] for SV-run24 h. PAF was more prevalent in patients with ESVEA: 19.6% vs. 2.8% for PAC/h >4 vs. ≤4 (p<0.001); 17.0% vs. 4.9% for SV-run24 h >5 vs. ≤5 beats (p = 0.003). Patients with PAF showed more supraventricular ectopic activity: 29 PAC/h [IQR 9; 143] vs. 4 PAC/h [1]; [14] and longest SV-run24 h = 10 [5]; [21] vs. 0 [0; 8] beats (both p<0.001). Both markers discriminated between the PAF- and the Non-PAF-group (area under receiver-operator-characteristics-curve 0.763 [95% CI 0.667; 0.858] and 0.716 [0.600; 0.832]). In multivariate analyses log(PAC/h) and log(SV-run24 h) were independently indicative of PAF. In Patients with PAC/h ≤4 and normal LAVI/a’ PAF was excluded, whereas those with PAC/h >4 and abnormal LAVI/a’ showed high PAF-rates.

Conclusions

ESVEA discriminated PAF from non-PAF beyond clinical factors including LAVI/a’ in patients with cerebral ischemia. Normal LAVI/a’+PAC/h ≤4 ruled out PAF, while prevalence was high in those with abnormal LAVI/a’+PAC/h >4.  相似文献   
108.
Periphyton plays an important functional role in the retention of nutrients in aquatic ecosystems, especially phosphorus. We evaluated the effects of enrichment with N and P and the effect after 20 days of no additional N and P on periphyton on artificial substratum in open-bottom mesocosms. The aim was to jointly evaluate periphyton, phytoplankton and zooplankton in the presence of macrophytes. Experimental conditions simulated natural conditions and nutrient addition was based on the maximum concentration recorded in mesotrophic reservoir. Our hypothesis is that the periphyton is sensitive to the effects of N and P enrichment and its interruption, despite the positive response of phytoplankton and zooplankton. Two treatments were designed using open-bottom mesocosms (n = 3): control (no nutrient addition); NP+ (combined phosphorus and nitrogen addition). Sampling for the measurement of biotic and abiotic variables was performed, with 10 days of continuous enrichment, on the 3rd, 6th and 11th, and 20 days after enrichment had ended (31st day). Periphyton chlorophyll a, dry mass and algal density increased significantly with the addition of N and P and decreased 20 days after the interruption of the enrichment. The highest periphyton P content was found in the NP+ treatment. The enrichment had a positive effect on Chrysophyceae (Chromulina spp.) and rotifer (Polyarthra spp.) density and the interruption of enrichment favored Bacillariophyceae (Gomphonema sp.) and rotifers (Gastropus stylifer). Phytoplankton responded positively to enrichment. Along with the high macrophyte coverage over the experimental period, we evidenced the positive effect enrichment had on phytoplankton biomass and zooplankton abundance. Therefore, periphyton on artificial substrate was sensitive to effects of N and P enrichment and its interruption, responding promptly to changes in nutrient availability in a scenario of high competition and grazing.  相似文献   
109.
Nanosized photonic explorers for bioanalysis with biologically localized embedding (PEBBLEs) have been created for the intracellular monitoring of small analytes (e.g. H(+), Ca(2+), Mg(2+), Zn(2+), O(2), K(+), Na(+), Cl(-), OH and glucose). The probes are based on the inclusion of fluorescent analyte-sensitive indicator dyes and analyte-insensitive reference dyes in a polymer (polyacrylamide, polydecylmethacrylate) or sol-gel (silica, ormosil) nanoparticle. The probes are ratiometric, reversible and protected from interaction with the cellular environment, a quality which is of benefit to the integrity of both the cell and the sensor functionalities. Herein we describe two types of PEBBLE sensors, direct measurement sensors and ion correlation sensors, as well as the use of these PEBBLEs in intracellular sensing.  相似文献   
110.
Cultured human choriocarcinoma JEG-3 cells secrete an immunosuppressor that inhibits lymphocyte proliferation stimulated by either an antigen or a mitogen. In this study, the immunosuppressive factor was characterized by three methods: ion-exchange and exclusion chromatography, partition in organic solvents, and thin-layer chromatography on silicic acid. This JEG-3 cell factor appeared to be a protein complex of about 150,000–200,000 Da that contained an immunologically active polar lipid. The structural and functional characteristics of JEG-3 cell immunosuppressor are similar if not identical to those of SIF, a suppressor lymphokine derived from T cells. These secretions from transformed trophoblastic cells may correspond to normal placental products or represent a function of malignant cells.  相似文献   
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