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71.
Respiratory anthrax, in the absence of early antibiotic treatment, is a fatal disease. This study aimed to test the efficiency of antibiotic therapy in curing infected animals and those sick with anthrax. Postexposure prophylaxis (24 h postinfection [p.i.]) of guinea pigs infected intranasally with Bacillus anthracis Vollum spores with doxycycline, ofloxacin, imipenem, and gentamicin conferred protection. However, upon termination of treatment, the animals died from respiratory anthrax. Combined treatment with antibiotics and active vaccination with a protective antigen-based vaccine leads to full protection even after cessation of treatment. Delaying the initiation of antibiotic administration to over 24 h p.i. resulted in treatment of animals with anthrax exhibiting various degrees of bacteremia and toxemia. Treatment with doxycycline or ciprofloxacin cured sick guinea pigs and rabbits exhibiting bacteremia levels up to 10(5) CFU/ml. Addition of anti-protective antigen (PA) antibodies augmented the efficiency of protection, allowing the cure of guinea pigs and rabbits with 10- to 20-fold-higher bacteremia levels, up to 7 × 10(5) CFU/ml and 2 × 10(6) CFU/ml, respectively. Treatment with ciprofloxacin and a monoclonal anti-PA antibody rescued rabbits with bacteremia levels up to 4 × 10(6) CFU/ml. During antibiotic administration, all surviving animals developed a protective immune response against development of a fatal disease and subcutaneous challenge with Vollum spores. In conclusion, these results demonstrate that antibiotic treatment can prevent the development of fatal disease in respiratory-anthrax-infected animals and can cure animals after disease establishment. A therapeutic time window of 40 h to 48 h from infection to initiation of efficient antibiotic-mediated cure was observed.  相似文献   
72.
73.
The current AHA-ECC guidelines for basic life support focus on the provision of good chest compressions with minimal interruptions for patients with presumed out-of-hospital cardiac arrest. Moreover, international consensus guidelines now support the use of chest compression-only cardiopulmonary resuscitation (CPR) instructions for dispatcher-assisted CPR given over the phone to untrained bystanders. However, evidence that strongly challenge these recommendations have been overlooked. A review of this evidence argues for the need for head rotation (a hands-free method of airway control) and abdominal compressions during bystander CPR.  相似文献   
74.
We previously described a new class of conserved, cell adhesive (haptotactic) peptides, termed Haptides, based on sequences first identified in fibrinogen. Here, we describe a new biomaterial, Haptide-coated Collagen, in which the carbodiimide reagent, EDC, was used to covalently couple a Haptide (preC gamma), equivalent to the carboxy terminus of the fibrinogen gamma chain, to a cross-linked sponge composed of bovine collagen type I. The dose response of Haptide bound to collagen on cell attachment response reached a plateau at a concentration of 5-10 mg Haptide/g collagen. The Haptized-collagen was more stable to 1N NaOH, with a degradation half-time (T(1/2)) of 1.7 h, compared to 0.9 h for untreated control. Haptized collagen discs could be loaded with approximately 30% more human dermal fibroblasts or bovine aortic endothelial cells than unmodified collagen discs (p < 0.001). After a proliferation phase, Haptized collagen discs contained approximately 45% more fibroblasts than non-Haptized discs (p < 0.01). Histological analysis following sub-dermal implantation in rats indicated that at day 8, Haptized collagen sponge was less degraded than unmodified collagen sponge, attracted more endogenous fibroblasts with newly deposited collagen, and provoked less inflammatory or other adverse reactions. These results suggest potential clinical applications for Haptized collagen sponge for tissue regeneration, soft tissue augmentation, skin repair, and wound healing.  相似文献   
75.
Trypanosoma brucei subspecies invade the brain parenchyma at late stages of human and experimental rodent infections. In this study, we compared the outcome of infection with T. b. brucei in MHC-matched (H-2b) C57BL/6 (B6) and 129Sv/Ev (Sv-129). Sv-129 showed higher parasitaemia and lower specific IgM (but not IgG) antibody levels than B6 mice. The number of trypanosomes, CD4+ and CD8+ T cells in the brain parenchyma was higher in B6 mice. B6 mice lost weight and showed higher cumulative mortality when compared with Sv-129 mice. Higher levels of IL-1β, IL-6, IL-10, TNF-α, IFN-γ, ICAM-1 and E-selectin, but low levels of TGF-β mRNA were present in brains of B6 when compared with Sv-129-infected mice. Thus, host genetics differentially determine the invasion of T. b. brucei into the brain parenchyma, which is paralleled by the severity of inflammation in the brain and course of the disease, but not by parasitaemia nor by antibody titres.  相似文献   
76.
A meta-analysis of emotional reactivity in major depressive disorder   总被引:12,自引:0,他引:12  
Three alternative views regarding how Major Depressive Disorder (MDD) alters emotional reactivity have been featured in the literature: positive attenuation (reduced positive reactivity), negative potentiation (increased negative reactivity), and emotion context insensitivity (ECI; reduced positive and negative reactivity). Although empirical studies have accumulated on emotional reactivity in MDD, this report is to our knowledge the first systematic quantitative review of this topic area. In omnibus analyses of 19 laboratory studies comparing the emotional reactivity of healthy individuals to that of individuals with MDD, MDD was characterized by reduced emotional reactivity to both positively and negatively valenced stimuli, with the reduction larger for positive stimuli (d=-.53) than for negative stimuli (d=-.25). Results were similar when 3 major emotion response systems (self-reported experience, expressive behavior, and peripheral physiology) were analyzed individually. The ECI view of emotional reactivity in MDD is well supported by laboratory data. Implications for the understanding of emotions in MDD are discussed.  相似文献   
77.
78.
Compromised respiratory sinus arrhythmia (RSA, i.e., low cardiac vagal control) frequently characterizes clinically depressed adults and also has been detected in infants of depressed mothers; however, its existence has not been established in older at-risk offspring. We investigated developmental patterns of RSA in a sample of 163 5- to 14-year-old children, who were either at high risk for depression (due to having a parent with a childhood-onset mood disorder) or low-risk for depression. We hypothesized that high-risk children have lower resting RSA than do low-risk children, which could reflect atypical developmental trajectories. Children's RSA was assessed during resting baseline periods on multiple occasions, typically 1-year apart. Linear growth modeling indicated a group by age interaction. Low-risk children (but not the high-risk children) exhibited a significantly increasing trajectory in resting RSA with age. Mood disorders in offspring did not account for the Group X Age interaction effect. Our study provides new evidence that children at high risk for depression have an atypical developmental trajectory of RSA across late childhood.  相似文献   
79.
80.
This study investigated associations between indiscriminate media reporting of suicides and later inflated suicide counts among Israel's general population between the years 2008 and 2012. Self-inflicted deaths that received post-suicide media exposure (referred to as “publicized suicides”) were selected via Google news search-hit appraisals. Distributions of suicides were inspected and risk ratios (RRs) estimated by comparing population suicide rates 4 weeks before and 4 weeks after each publicized suicide (“reference” vs. “affected” periods, respectively). Poisson time series regression was employed to account also for secular trends and seasonality. A total of 2,119 people died by suicide, 13 of whom received noticeable media attention throughout the study. No meaningful impact following the 13 deaths on subsequent suicide counts during the observation window (affected vs. reference phase) was found. Poisson regression confirmed that suicide counts following publicized suicides were independent of media coverage. Given the pronounced search hits following the publicized suicides developing regulation practices that constrain indiscreet media reporting should officially be included as part of suicide prevention practices. Future research should focus on imitation suicide effects as a function of post-suicide media exposure, while including both risk and protective factors.  相似文献   
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