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71.
The present study was designed to investigate the prevalence of the pathogenic coccidia species Eimeria bovis and Eimeria zuernii in shed-reared animals in German dairy and fattening facilities. Samples were obtained from 65 cattle farms distributed randomly across all the regions of Germany regardless of the occurrence of clinical problems. The samples were obtained rectally. Faecal consistency and the total number of oocysts per gram of faeces (OPG) were determined, along with the OPG values for E. bovis and E. zuernii. A questionnaire was completed for each farm to record information about herd size and management, along with individual animal data. Eimeria oocysts were detected in 62 of these farms, which give a prevalence of 95.4%. The farm prevalence of the pathogenic species was 76.9% for E. bovis and 83.1% for E. zuernii. The number of oocysts excreted could not be correlated significantly with farm type or farm management but depended on the floor type, the age of the calves and the time after rehousing. Furthermore, there was a positive correlation between OPG and the observation of diarrhoea. E. zuernii had a greater influence on the occurrence of diarrhoea than E. bovis. This study confirms that herd management frequently does not meet the requirements of effective coccidia control despite the fact that the pathogenic coccidia E. bovis and E. zuernii are ubiquitous in German cattle populations.  相似文献   
72.
Hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channels represent the molecular substrate of the hyperpolarization-activated inward current (Ih). Although these channels act as pacemakers for the generation of rhythmic activity in the thalamocortical network during sleep and epilepsy, their developmental profile in the thalamus is not yet fully understood. Here we combined electrophysiological, immunohistochemical, and mathematical modeling techniques to examine HCN gene expression and Ih properties in thalamocortical relay (TC) neurons of the dorsal part of the lateral geniculate nucleus (dLGN) in an epileptic (WAG/Rij) compared to a non-epileptic (ACI) rat strain. Recordings of TC neurons between postnatal day (P) 7 and P90 in both rat strains revealed that Ih was characterized by higher current density, more hyperpolarized voltage dependence, faster activation kinetics, and reduced cAMP-sensitivity in epileptic animals. All four HCN channel isoforms (HCN1-4) were detected in dLGN, and quantitative analyses revealed a developmental increase of protein expression of HCN1, HCN2, and HCN4 but a decrease of HCN3. HCN1 was expressed at higher levels in WAG/Rij rats, a finding that was correlated with increased expression of the interacting proteins filamin A (FilA) and tetratricopeptide repeat-containing Rab8b-interacting protein (TRIP8b). Analysis of a simplified computer model of the thalamic network revealed that the alterations of Ih found in WAG/Rij rats compensate each other in a way that leaves Ih availability constant, an effect that ensures unaltered cellular burst activity and thalamic oscillations. These data indicate that during postnatal developmental the hyperpolarizing shift in voltage dependency (resulting in less current availability) is compensated by an increase in current density in WAG/Rij thereby possibly limiting the impact of Ih on epileptogenesis. Because HCN3 is expressed higher in young versus older animals, HCN3 likely does not contribute to alterations in Ih in older animals.  相似文献   
73.
Aims

We aimed to analyze prevalence and predictors of NOAC off-label under-dosing in AF patients before and after the index stroke.

Methods

The post hoc analysis included 1080 patients of the investigator-initiated, multicenter prospective Berlin Atrial Fibrillation Registry, designed to analyze medical stroke prevention in AF patients after acute ischemic stroke.

Results

At stroke onset, an off-label daily dose was prescribed in 61 (25.5%) of 239 NOAC patients with known AF and CHA2DS2-VASc score ≥ 1, of which 52 (21.8%) patients were under-dosed. Under-dosing was associated with age ≥ 80 years in patients on rivaroxaban [OR 2.90, 95% CI 1.05–7.9, P = 0.04; n = 29] or apixaban [OR 3.24, 95% CI 1.04–10.1, P = 0.04; n = 22]. At hospital discharge after the index stroke, NOAC off-label dose on admission was continued in 30 (49.2%) of 61 patients. Overall, 79 (13.7%) of 708 patients prescribed a NOAC at hospital discharge received an off-label dose, of whom 75 (10.6%) patients were under-dosed. Rivaroxaban under-dosing at discharge was associated with age ≥ 80 years [OR 3.49, 95% CI 1.24–9.84, P = 0.02; n = 19]; apixaban under-dosing with body weight ≤ 60 kg [OR 0.06, 95% CI 0.01–0.47, P < 0.01; n = 56], CHA2DS2-VASc score [OR per point 1.47, 95% CI 1.08–2.00, P = 0.01], and HAS-BLED score [OR per point 1.91, 95% CI 1.28–2.84, P < 0.01].

Conclusion

At stroke onset, off-label dosing was present in one out of four, and under-dosing in one out of five NOAC patients. Under-dosing of rivaroxaban or apixaban was related to old age. In-hospital treatment after stroke reduced off-label NOAC dosing, but one out of ten NOAC patients was under-dosed at discharge.

Clinical trial registration

NCT02306824.

  相似文献   
74.
Stressful and traumatic events can create aversive memories, which are a predisposing factor for anxiety disorders. The amygdala is critical for transforming such stressful events into anxiety, and the recently discovered neuropeptide S transmitter system represents a promising candidate apt to control these interactions. Here we test the hypothesis that neuropeptide S can regulate stress-induced hyperexcitability in the amygdala, and thereby can interact with stress-induced alterations of fear memory. Mice underwent acute immobilization stress (IS), and neuropeptide S and a receptor antagonist were locally injected into the lateral amygdala (LA) during stress exposure. Ten days later, anxiety-like behavior, fear acquisition, fear memory retrieval, and extinction were tested. Furthermore, patch-clamp recordings were performed in amygdala slices prepared ex vivo to identify synaptic substrates of stress-induced alterations in fear responsiveness. (1) IS increased anxiety-like behavior, and enhanced conditioned fear responses during extinction 10 days after stress, (2) neuropeptide S in the amygdala prevented, while an antagonist aggravated, these stress-induced changes of aversive behaviors, (3) excitatory synaptic activity in LA projection neurons was increased on fear conditioning and returned to pre-conditioning values on fear extinction, and (4) stress resulted in sustained high levels of excitatory synaptic activity during fear extinction, whereas neuropeptide S supported the return of synaptic activity during fear extinction to levels typical of non-stressed animals. Together these results suggest that the neuropeptide S system is capable of interfering with mechanisms in the amygdala that transform stressful events into anxiety and impaired fear extinction.  相似文献   
75.
The objective of the study was to use 320-detector row 4D CT angiography (CTA) for measuring cerebral circulation times (CCT) and to assess early venous drainage (EVD) and shortening of CCT in arteriovenous malformations (AVM) and to compare with DSA. CCT of 12 physiological patients and five AVM patients were acquired using a 4D CTA protocol by recording cerebrovascular bolus passage time. In the AVM patients EVD time (EVDT) was measured. Identical measurements were performed on DSA for the AVM patients. It was found that the physiological CCTs were 5.8 ± 1.4 s (M ± SD). EVD was seen in all AVMs and resulted in a shortened CCT of 3.4 ± 1.1 s (p = 0.01). There was no significant difference for CCT and EVDT values derived from DSA and 4D CTA. Thus, the CCTs can be measured non-invasively using clinical 4D CTA. Early venous drainage with shortened CCTs was observed by 4D CTA in all five patients with AVMs.  相似文献   
76.

Objective

Depressive symptoms are highly relevant for the quality of life, health behavior, and prognosis in patients with coronary artery disease (CAD). However, previous psychotherapy trials in depressed CAD patients produced small to moderate effects on depression, and null effects on cardiac events. In this multicentre psychotherapy trial, symptoms of depression are treated together with the Type D pattern (negative affectivity and social inhibition) in a stepwise approach.

Methods

Men and women (N=569, age 18–75 years) with any manifestation of CAD and depression scores ≥ 8 on the Hospital Anxiety and Depression Scale (HADS), will be randomized (allocation ratio 1:1) into the intervention or control group. Patients with severe heart failure, acutely life-threatening conditions, chronic inflammatory disease, severe depressive episodes or other severe mental illness are excluded. Both groups receive usual medical care. Patients in the intervention group receive three initial sessions of supportive individual psychotherapy. After re-evaluation of depression (weeks 4–8), patients with persisting symptoms receive an additional 25 sessions of combined psychodynamic and cognitive–behavioral group therapy. The control group receives one psychosocial counseling session. Primary efficacy variable is the change of depressive symptoms (HADS) from baseline to 18 months. Secondary endpoints include cardiac events, remission of depressive disorder (SCID) and Type D pattern, health-related quality of life, cardiovascular risk profile, neuroendocrine and immunological activation, heart rate variability, and health care utilization, up to 24 months of follow-up (ISRCTN: 76240576; NCT00705965). Funded by the German Research Foundation.  相似文献   
77.
78.
The aim of this study was to investigate the molecular and protein expression pattern of markers of stemness phenotype and its clinicopathological significance in human biliary tract cancer (BTC). Human BTC cell lines (CCLP-1, Egi-1, MzChA-1, MzChA-2, SkChA-1, TFK-1 and GBC) were analyzed in vitro and in xenotransplanted animals for expression of markers of stemness and compared to tissue microarrays (TMA) of 34 cases of human BTC with complete pathomorphological and clinical data (survival). Molecular analyses on the mRNA and protein level included makers of stemness and progenitor (Bmi-1, Sox-2, Nestin, CD133, CD44 and Nanog), proliferation and differentiation (cell cycle proteins, intermediate filaments). The investigated BTC samples showed a low to moderate and partially significantly different expression pattern of the stem cell markers in vitro, in vivo and in TMA. Hierarchical cluster analysis identified subgroups with homogenous expression of stem cell markers significantly differing with respect to cytokeratin expression in xenografts and Ki67 proliferation marker in human TMA, respectively - thus indicating possible heterogeneous carcinogenesis pathways in BTC. Additionally, these stem cell markers could be linked to morphology and molecular markers of proliferation and differentiation on the mRNA and protein level. Finally, survival analysis identified the combination of CD133 and CD44 as an independent prognostic factor yet their value as prognostic factors need testing in prospective study design.  相似文献   
79.
The canonical view on the central amygdala has evolved from a simple output station towards a highly organized microcircuitry, in which types of GABAergic neurons in centrolateral (CeL) and centromedial (CeM) subnuclei regulate fear expression and generalization. How these specific neuronal populations are connected to extra-amygdaloid target regions remains largely unknown. Here we show in mice that a subpopulation of GABAergic CeL and CeM neurons projects monosynaptically to brainstem neurons expressing neuropeptide S (NPS). The CeL neurons are PKCδ-negative and are activated during conditioned fear. During fear memory retrieval, the efficacy of this GABAergic influence on NPS neurons is enhanced. Moreover, a large proportion of these neurons (~50%) contain prodynorphin and somatostatin, two neuropeptides inhibiting NPS neurons. We conclude that CeL and CeM neurons inhibit NPS neurons in the brainstem by GABA release and that efficacy of this connection is strengthened upon fear memory retrieval. Thereby, this pathway provides a possible feedback mechanism between amygdala and brainstem routes involved in fear and stress coping.  相似文献   
80.
Myelin/oligodendrocyte glycoprotein (MOG) is a surface-exposed antigen of myelin and an important target for autoimmune responses which mediate inflammatory demyelination in the central nervous system. Experimentally, MOG induces strong pathogenic T cell responses in many strains of laboratory animals. Immunological studies in humans also identify MOG as a surprisingly prevalent antigenic molecule among the myelin proteins. In addition, the encephalitogenic properties of MOG are linked to the induction of antibody responses which have been demonstrated to directly promote central nervous system demyelination, a hallmark neuropathological feature in disorders such as human multiple sclerosis. Factors responsible for autoimmunity to MOG likely include genetic influences as well as other mechanisms, which are the subject of intense investigation. This article reviews experimental data currently available on specificity and pathogenic roles of T cell and antibody responses against MOG, which have implications relevant to multiple sclerosis and related disorders.  相似文献   
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