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61.
Bystander effects have been proposed as a third action pathway of ionising radiation besides direct and indirect effects. The purpose of the study was to investigate whether expression of interleukin-1alpha (IL-1alpha) and beta1-integrin is elevated in bystander cells as a marker for bystander effects in comparison with classical markers such as the clonogenic assay, apoptosis and the presence of micronuclei. The hybrid cell line E.A. hy.926 obtained by fusion of HUVEC cells with the epithelial cell line A 459 was irradiated with 0-5 Gy. Bystander effects were established via medium transfer at 45 min and 4 h after irradiation from irradiated to nonirradiated cell populations. In order to exclude effects of the irradiated medium itself, irradiated medium only was also used for transfer to nonirradiated cells. Then, cells were fixed at 1, 2, 6, and 24 h after irradiation or medium transport and IL-1alpha and beta1-integrin were detected and evaluated. A higher number of beta1-integrin-positive cells was observed in both irradiated and bystander cell populations than in the control group at 1 and 24 h after irradiation with 1 Gy or medium transfer. Significantly higher numbers of IL-1alpha-positive cells were found at 1, 2, and 6 h after irradiation with 1 Gy or medium transfer as well as at 2 and 6 h after irradiation with 5 Gy or medium transfer. Clonogenic survival decreased dependently on the dose in irradiated cells but did not show any significant difference between the bystander cell populations and sham-irradiated cells. The irradiated medium itself did not have any effect. It is concluded that beta1-integrin and IL-1alpha expression may serve as more sensitive markers of post-irradiation responses in bystander cell populations than the classical radiobiological markers. Moreover, overexpression of beta1-integrin and IL-1alpha may induce increased susceptibility to inflammation of bystander cells.  相似文献   
62.
In comparison to explicit learning, implicit learning is hypothesized to be a phylogenetically older form of learning that is important in early developmental processes (e.g., natural language acquisition, socialization) and relatively impervious to individual differences in age and IQ. We examined implicit learning in a group of children and adults (9-49 years of age) with Williams syndrome (WS) and in a comparison group of typically developing individuals matched for chronological age. Participants were tested in an artificial-grammar learning paradigm and in a rotor-pursuit task. For both groups, implicit learning was largely independent of age. Both groups showed evidence of implicit learning but the comparison group outperformed the WS group on both tasks. Performance advantages for the comparison group were no longer significant when group differences in working memory or nonverbal intelligence were held constant.  相似文献   
63.
A genetic knock out was used to determine the specific contribution of G(q)/G(11)-family G-proteins to the function of thalamocortical relay (TC) neurons. Disruption of Galpha(q) function in a conditional forebrain-specific Galpha(q)/Galpha(11)-double-deficient mouse line [Formula: see text] had no effects on the resting membrane potential (V (rest)) and the amplitude of the standing outward current (I (SO)). Stimulation of muscarinic acetylcholine (ACh) receptors (mAChR; muscarine, 50 muM) induced a decrease in I (SO) amplitude in wild-type mice (36 +/- 4%, n = 5), a constitutive Galpha(11)-deficient mouse line ([Formula: see text]; 36 +/- 3%, n = 8), and [Formula: see text] (11 +/- 2%, n = 16). Current-clamp recordings revealed a muscarine-induced positive shift in V (rest) of 23 +/- 2 mV (n = 6), 18 +/- 5 mV (n = 5), and 2 +/- 1 mV (n = 9) in wild type, [Formula: see text], and [Formula: see text], respectively. This depolarization was associated with a change in TC neuron activity from burst to tonic firing in wild type and [Formula: see text], but not in [Formula: see text]. The use of specific antibodies and of pharmacological agents with preferred affinity points to the contribution of m(1)AChR and m(3)AChR. In conclusion, we present two novel aspects of the physiology of the thalamocortical system by demonstrating that the depolarization of TC neurons, which is induced by the action of transmitters of ascending brainstem fibers, is governed roughly equally by both m(1)AChR and m(3)AChR and is transduced by Galpha(q) but not by Galpha(11).  相似文献   
64.
MenBvac is an outer membrane vesicle vaccine against systemic meningococcal disease caused by serogroup B Neisseria meningitidis. In this placebo-controlled double-blind study including 374 healthy adolescents, the safety and immunogenicity of a schedule of three primary doses 6 weeks apart followed by a fourth dose a year later were evaluated. Antibody responses to the vaccine strain and heterologous strains (non-vaccine-type strains) and the persistence of these antibodies were measured by the serum bactericidal assay (SBA) and enzyme-linked immunosorbent assay up to 1 year after the last dose. The proportion of subjects with SBA titers of > or = 4 against the vaccine strain increased from 3% prevaccination to 65% after the third dose. Ten months later, this proportion had declined to 28%. The fourth dose induced a booster response demonstrated by 93% of subjects achieving a titer of > or = 4. One year after the booster dose, 64% still showed SBA titers of > or = 4. Cross-reacting antibodies were induced against all heterologous strains tested, although the magnitude of SBA titers differed widely between the different strains. All four doses of MenBvac were safe. Both MenBvac and the placebo had reactogenicity profiles of mild to moderate local and systemic reactions. Pain, the most common reaction, was reported with similar frequencies in both groups. No serious adverse events occurred in the MenBvac group. This study confirmed the good immunogenicity of the primary course of MenBvac and demonstrated prolonged persistence and increased cross-reactivity of functional antibodies elicited by a booster dose.  相似文献   
65.
66.

Aim

Perturbed calcium homeostasis limits life expectancy in familial hypomagnesaemia with hypercalciuria and nephrocalcinosis (FHHNC). This rare disease occurs by loss-of-function mutations in CLDN16 or CLDN19 genes, causing impaired paracellular reabsorption of divalent cations along the cortical thick ascending limb (cTAL). Only partial compensation takes place in the ensuing late distal convoluted tubule, connecting tubule, and collecting duct, where the luminal transient receptor potential channel V5 (TRPV5), as well as basolateral plasma membrane calcium ATPase (PMCA) and sodium-potassium exchanger (NCX1) mediate transcellular Ca2+ reabsorption. The loop diuretic furosemide induces compensatory activation in these distal segments. Normally, furosemide enhances urinary calcium excretion via inhibition of the aforementioned cTAL. As Ca2+ reabsorption in the cTAL is already severely impaired in FHHNC patients, furosemide may alleviate hypercalciuria in this disease by activation of the distal transcellular Ca2+ transport proteins.

Methods

Cldn16-deficient mice (Cldn16−/−) served as a FHHNC model. Wild-type (WT) and Cldn16−/− mice were treated with furosemide (7 days of 40 mg/kg bw) or vehicle. We assessed renal electrolyte handling (metabolic cages) and key divalent transport proteins.

Results

Cldn16−/− mice show higher Ca2+ excretion than WT and compensatory stimulation of Cldn2, TRPV5, and NCX1 at baseline. Furosemide reduced hypercalciuria in Cldn16−/− mice and enhanced TRPV5 and PMCA levels in Cldn16−/− but not in WT mice.

Conclusions

Furosemide significantly reduces hypercalciuria, likely via upregulation of luminal and basolateral Ca2+ transport systems in the distal nephron and collecting duct in this model for FHHNC.  相似文献   
67.

Background

Mental health problems among trafficked persons could be the result of concomitantly interwoven effects of various factors. Analyzing the networked relationships concurrently could be a more substantive approach to better understand the role of risk factors in this population. This study aimed to assess the magnitude of mental health symptoms as well as the association among socio-demographic, trafficking related exposure variables, and mental health problems of Ethiopian returnees from trafficking.

Methods

A sample of 1387 returnees who were trafficked via three major human trafficking corridors of Ethiopia were selected consecutively. Data related to socio-economic, trafficking exposure variables, and symptoms of mental illness were collected in personal interviews. Anxiety was measured with a brief measure for generalized anxiety disorder (GAD-7), depression with a patient health questionnaire (PHQ-9), and PTSD with post-traumatic checklist (PCL-C). Generalized structural equation modeling was employed to estimate the relationships among exogenous, mediating, and endogenous variables simultaneously.

Results

The prevalence of symptoms of anxiety was estimated at 51.9% (95% CI 49.3–54.6%); PTSD was estimated at 34.5% (95% CI 32.1–37.1%) and depression at 58.3% (95% CI 55.6–60.9%). Restricted freedom of movement had a direct positive effect on anxiety (β?=?1.24, 95% CI 0.97–1.51), depression (β?=?0.94, 95% CI 0.71–1.17) and PTSD (13.00, 95% CI 11.23–14.77). Violence experienced during the trafficking period was a mediator variable and significantly associated with anxiety (β?=?0.46; 95% CI 0.26–0.66) and PTSD (β?=?4.00; 95% CI 2.06–5.94). History of detention had a positive total effect on GAD (total β?=?1.380, 95% CI 1.074–1.687) and PTSD (total β?=?15.63, 95% CI 13.708–17.545), and direct positive effect on depression (β?=?0.89, 95% CI 0.65–1.13).

Conclusion

Ethiopian trafficked persons were highly likely to return with increased levels of mental health symptoms, namely anxiety, depression, and PTSD. Socio-economic and trafficking related exposures mediated by violence were factors affecting mental health symptoms. Thus, in addition to economic re-integrations of victims, strategies should be designed and implemented to address the prevalent mental health problems.
  相似文献   
68.
ObjectivesTo present long-term outcome and to identify predictors of seizure freedom after vagus nerve stimulation (VNS).MethodsAll patients who had undergone VNS implantation in the Epilepsy Centre Bethel were retrospectively reviewed. There were 144 patients who had undergone complete presurgical evaluation, including detailed clinical history, magnetic resonance imaging, and long-term video-EEG with ictal and interictal recordings. After implantation, all patients were examined at regular intervals of 4 weeks for 6–9 months. During this period the antiepileptic medication remained constant. All patients included in this study were followed up for a minimum of 2 years.ResultTen patients remained seizure-free for more than 1 year after VNS implantation (6.9%). Seizures improved in 89 patients (61.8%) but no changes were observed in 45 patients (31.3%). The following factors were significant in the univariate analysis: age at implantation, multifocal interictal epileptiform discharges, unilateral interictal epileptiform discharge, cortical dysgenesis, and psychomotor seizure. Stepwise multivariate analysis showed that unilateral interictal epileptiform discharges (IEDs), P = 0.014, HR = 0.112 (95% CIs, 0.019–0.642), cortical dysgenesis P = 0.007, HR = 0.065 (95% CIs, 0.009–0.481) and younger age at implantation P = 0.026, HR = 7.533 (95% CIs 1.28–44.50) were independent predictors of seizure freedom in the long-term follow-up.ConclusionVNS implantation may render patients with some forms of cortical dysgenesis (parietooccipital polymicrogyria, macrogyria) seizure-free. Patients with unilateral IEDs and earlier implantation achieved the most benefit from VNS.  相似文献   
69.
Contextual cueing refers to the facilitated ability to locate a particular visual element in a scene due to prior exposure to the same scene. This facilitation is thought to reflect implicit learning, as it typically occurs without the observer's knowledge that scenes repeat. Unlike most other implicit learning effects, contextual cueing can be impaired following damage to the medial temporal lobe. Here we investigated neural correlates of contextual cueing and explicit scene memory in two participant groups. Only one group was explicitly instructed about scene repetition. Participants viewed a sequence of complex scenes that depicted a landscape with five abstract geometric objects. Superimposed on each object was a letter T or L rotated left or right by 90°. Participants responded according to the target letter (T) orientation. Responses were highly accurate for all scenes. Response speeds were faster for repeated versus novel scenes. The magnitude of this contextual cueing did not differ between the two groups. Also, in both groups repeated scenes yielded reduced hemodynamic activation compared with novel scenes in several regions involved in visual perception and attention, and reductions in some of these areas were correlated with response-time facilitation. In the group given instructions about scene repetition, recognition memory for scenes was superior and was accompanied by medial temporal and more anterior activation. Thus, strategic factors can promote explicit memorization of visual scene information, which appears to engage additional neural processing beyond what is required for implicit learning of object configurations and target locations in a scene.  相似文献   
70.

Purpose

To determine whether pre-treatment hemoglobin (Hb) levels in patients with bladder cancer impact on oncological outcomes after radical cystectomy (RC).

Methods

A consecutive, contemporary series of 246 patients undergoing RC and pelvic lymph node dissection for bladder cancer. Decreased Hb level was defined as ≤12 g/dL. The Kaplan–Meier method was used to estimate recurrence-free (RFS), cancer-specific (CSS) and overall survival (OS). The Fisher exact/Chi-square test was used to investigate differences between both groups. Uni- and multivariable Cox regression analysis addressed risk factors for recurrence, cancer-specific death and overall death. The median follow-up was 30 months (2–116).

Results

Of the 246 patients, 182 (74 %) had normal (>12 g/dL) and 64 decreased (≤12 g/dL) preoperative Hb (26 %). In univariable analysis, decreased Hb was associated with increased age, extravesical disease, hydronephrosis (all p < 0.001), node-positive disease and positive resection margins (both p = 0.01). Subanalyzed for patients with organ-confined disease (defined as ≤pT2bN0R0; N = 109), the 3-year RFS, CSS and OS was significantly lower in patients with decreased (34.9, 35.5 and 19.8 %) compared to normal Hb level (69.7, 86.3 and 77.6 %; p = 0.01/p = 0.002/p < 0.001). In multivariable analysis, RFS, CSS and OS were significantly lower in patients with decreased Hb (p = 0.007, p = 0.001 and p = 0.002), pathologically locally advanced tumor (≥pT3a; p = 0.023, p = 0.036 and p = 0.065) and nodal stage (p < 0.001, p = 0.006 and p = 0.001) and positive soft tissue surgical margins (p = 0.040, p = 0.004 and 0.012).

Conclusions

Pre-cystectomy Hb levels are associated with adverse histopathologic characteristics and provide additional prognostic information especially for patients with pathologically localized bladder cancer.
  相似文献   
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