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81.
Healthcare personnel are recognized to be at higher risk for infection with severe acute respiratory syndrome coronavirus 2. We conducted a serologic survey in 15 hospitals and 56 nursing homes across Rhode Island, USA, during July 17–August 28, 2020. Overall seropositivity among 9,863 healthcare personnel was 4.6% (95% CI 4.2%–5.0%) but varied 4-fold between hospital personnel (3.1%, 95% CI 2.7%–3.5%) and nursing home personnel (13.1%, 95% CI 11.5%–14.9%). Within nursing homes, prevalence was highest among personnel working in coronavirus disease units (24.1%; 95% CI 20.6%–27.8%). Adjusted analysis showed that in hospitals, nurses and receptionists/medical assistants had a higher likelihood of seropositivity than physicians. In nursing homes, nursing assistants and social workers/case managers had higher likelihoods of seropositivity than occupational/physical/speech therapists. Nursing home personnel in all occupations had elevated seropositivity compared with hospital counterparts. Additional mitigation strategies are needed to protect nursing home personnel from infection, regardless of occupation.  相似文献   
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83.
Reactive nitrogen species (RNS) and reactive oxygen species (ROS), collectively known as reactive oxygen and nitrogen species (RONS), are the products of normal cellular metabolism and interact with several vital biomolecules including nucleic acid, proteins, and membrane lipids and alter their function in an irreversible manner which can lead to cell death. There is an imperative role for oxidative stress in the pathogenesis of cognitive impairments and the development and progression of neural injury. Elevated production of higher amounts of nitric oxide (NO) takes place in numerous pathological conditions, such as neurodegenerative diseases, inflammation, and ischemia, which occur concurrently with elevated nitrosative/oxidative stress. The enzyme nitric oxide synthase (NOS) is responsible for the generation of NO in different cells by conversion of L-arginine (Arg) to L-citrulline. Therefore, the NO signaling pathway represents a viable therapeutic target. Naturally occurring polyphenols targeting the NO signaling pathway can be of major importance in the field of neurodegeneration and related complications. Here, we comprehensively review the importance of NO and its production in the human body and afterwards highlight the importance of various natural products along with their mechanisms against various neurodegenerative diseases involving their effect on NO production.  相似文献   
84.
Endocannabinoids play a crucial neuromodulator role in both physiological and pathological states in various brain regions including the prefrontal cortex (PFC). We examined, whether presynaptic cannabinoid receptors are involved in the modulation of basal and electrical field stimulation-evoked [3H]norepinephrine ([3H]NE) release from rat PFC slices. WIN55,212-2, a nonselective CB1 receptor (CB1R) agonist, inhibited the electrical stimulation-evoked efflux of [3H]NE in a concentration-dependent fashion, which was antagonized by the CB1R antagonist/inverse agonist, AM251 (1 μM). Idazoxan, a selective α2-adrenoceptor antagonist, augmented the evoked [3H]NE release. In the presence of idazoxan, the effect of WIN55,212-2 was exacerbated or attenuated, depending on the applied concentration and stimulation frequency. Moreover their combined, but not individual application elicited a depressive-like phenomenon in the forced-swim test. These data were bolstered with fluorescent and confocal microscopy analysis, which revealed that CB1R immunoreactivity co-localized with dopamine-β-hydroxylase positive (i.e. noradrenergic) fibers and the inhibitory α2A adrenergic autoreceptors (α2AR) in the PFC. Furthermore, idazoxan triggered a decrease in CB1R density in the PFC, suggesting that high extracellular level of norepinephrine downregulates CB1Rs.  相似文献   
85.
Abstract: A growing body of evidence has pointed to the blockade of the N‐methyl‐d ‐aspartate (NMDA) receptor signaling as a potential therapeutic target for the treatment of major depression. The present study was aimed to evaluate behavioural and molecular effects of the chronic treatment with ketamine and imipramine in rats. To this aim, rats were 14 days treated once a day with ketamine (5, 10 and 15 mg/kg) and imipramine (10, 20 and 30 mg/kg) and then subjected to the forced swimming and open‐field tests. Ketamine and imipramine, at the all doses tested, reduced immobility time, and increased both climbing and swimming time of rats compared to the saline group, without affecting spontaneous locomotor activity. Brain‐derived neurotrophic factor (BDNF) hippocampal levels were assessed in imipramine‐ and ketamine‐treated rats by ELISA sandwich assay. Chronic administration of both drugs, ketamine and imipramine, did not modify BDNF protein levels in the rat hippocampus. In conclusion, our findings demonstrate for the first time that chronic administration of acute inactive doses of ketamine (5 mg/kg) becomes active after chronic treatment, while no signs of tolerance to the behavioural effects of ketamine were observed after chronic administration of acute active doses (10 and 15 mg/kg). Finally, these findings further support the hypothesis that NMDA receptor could be a new pharmacological target for the treatment of mood disorders.  相似文献   
86.
To estimate seroprevalence of severe acute respiratory syndrome 2 (SARS-CoV-2) among healthcare, first response, and public safety personnel, antibody testing was conducted in emergency medical service agencies and 27 hospitals in the Detroit, Michigan, USA, metropolitan area during May–June 2020. Of 16,403 participants, 6.9% had SARS-CoV-2 antibodies. In adjusted analyses, seropositivity was associated with exposure to SARS-CoV-2–positive household members (adjusted odds ratio [aOR] 6.18, 95% CI 4.81–7.93) and working within 15 km of Detroit (aOR 5.60, 95% CI 3.98–7.89). Nurse assistants (aOR 1.88, 95% CI 1.24–2.83) and nurses (aOR 1.52, 95% CI 1.18–1.95) had higher likelihood of seropositivity than physicians. Working in a hospital emergency department increased the likelihood of seropositivity (aOR 1.16, 95% CI 1.002–1.35). Consistently using N95 respirators (aOR 0.83, 95% CI 0.72–0.95) and surgical facemasks (aOR 0.86, 95% CI 0.75–0.98) decreased the likelihood of seropositivity.  相似文献   
87.
ABSTRACT

Lifestyle interventions may reduce inflammation and lower breast cancer (BrCa) risk. This randomized trial assessed the impact of the Sistas Inspiring Sistas Through Activity and Support (SISTAS) study on plasma C-reactive protein (CRP), interleukin-6 (IL-6) and Dietary Inflammatory Index (DII). This unblinded, dietary and physical activity trial was implemented in 337 obese (body mass index [BMI] ≥30 kg/m2) African American (AA) women recruited between 2011 and 2015 in South Carolina through a community-based participatory approach with measurements at baseline, 3 months, and 12 months. Participants were randomized into either intervention (n = 176) or wait-list control group (n = 161). Linear mixed-effect models were used for analyses of CRP and IL-6. Baseline CRP was significantly higher in those with greater obesity, body fat percentage, and waist circumference (all p <.01). No difference was observed between groups for CRP or IL-6 at 3 or 12 months; however, improvements in diet were observed in the intervention group compared to the control group (p = .02) at 3 months but were not sustained at 12 months. Although the intervention was not successful at reducing levels of CRP or IL-6, a significant decrease was observed in DII score for the intervention group, indicating short-term positive dietary change.  相似文献   
88.
Objectives. We describe the impact of school health centers in Alameda County, California, on adolescents'' access to care and their mental and physical health outcomes.Methods. We used a multimethod evaluation of 12 school health centers to track data on clients (n = 7410), services, and provider-reported outcomes; client pre–post surveys (n = 286); and student focus groups (n = 105 participants).Results. School health centers were the most commonly reported source of medical (30%), family planning (63%), and counseling (31%) services for clients. Mental health providers reported significant improvements (P < .05) from baseline to follow-up in clients'' presenting concerns and resiliency factors. Medical providers and clients also reported general improvements in reproductive health, particularly in the use of birth control other than condoms. Student focus group participants noted that school health centers helped improve access to services students might not seek out otherwise, particularly counseling and family planning services. Furthermore, students noted that they liked school health centers because of their confidentiality, free services, convenience, and youth-friendly staff.Conclusions. School health centers increase access to care and improve mental health, resiliency, and contraceptive use.School-based and school-linked health centers (hereafter “school health centers”) represent a model of care that responds to the unique physical and mental health issues of adolescents by offering care in an accessible, youth-friendly environment. Studies have found that access to school health centers increases use of primary care, reduces use of emergency rooms, and results in fewer hospitalizations.13 School health centers also expand access to and quality of care for underserved adolescents; one study found that school health center users were more likely than were traditional outpatient clients to have received primary and preventive care services despite the fact that they were less likely to be insured.4 Furthermore, adolescents with alternate forms of health care report high degrees of comfort-seeking care at school health centers.5Adolescent mental health outcomes have also improved because of school health centers. Studies have shown a significant decline in depression among students who received school health center mental health services6 and a reduced likelihood of suicide ideation among students attending schools with school health centers.7 Studies have also documented the positive impact of school health centers on reproductive health outcomes,8 including improved contraceptive use.9Although research has demonstrated how the school health center model of care can affect health access and outcomes, many studies have been limited by relatively small sample sizes. Collecting uniform outcome data from larger coalitions of school health centers is challenging, given the obstacles of different school districts, community health providers, service structures, and data confidentiality regulations. Our aim was to demonstrate the impact of 12 school health centers on clients'' access to care, satisfaction, and reproductive and mental health outcomes. We incorporated data collection from both client and provider perspectives through a standardized evaluation process that documents services provided, as well as provider assessments of 2 outcome measures that school health centers have been known to affect: reproductive health and mental health.  相似文献   
89.
Natural antioxidants, including polyphenols, flavonoids, anthocyanins and carotenoids, play an important role in the treatment and prevention of a large number of diseases. However, studies indicate that natural antioxidants can act as prooxidants, which produce free radicals and cause DNA damage and mutagenesis. The prooxidant activity is typically catalyzed by metals, particularly transition metals such as Fe and Cu, present in biological systems. In this article, we aim to review new in vitro and in vivo evidence of the prooxidant activity of phenolics, flavonoids, anthocyanins and carotenoids. We highlight the role of catalyzing metals, including transition metals, non‐transition metals and metalloids, in the prooxidant activity of natural antioxidants. Prooxidant structure–activity relationships of simple phenolics, flavonoids and anthocyanins and the role of cellular antioxidant defense, including endogenous antioxidant compounds and antioxidant enzymes, are also addressed in this review. In addition, we discuss the question, With respect to in vitro evidence of the prooxidant activity of antioxidants, can we translate this activity into biological systems and the human body? Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
90.
Objective: To determine how medical and nursing staff treat feverish children and compare the findings with their theoretical knowledge, evaluating how they might contribute to fever phobia in parents.Setting: Paediatric Emergency Department.Method: In the first step, we analysed prospectively the files of all children having consulted the Paediatric Emergency Department with a history of fever or of body temperature above 38 °C during a 2-week period. The second step consisted of evaluating knowledge and perception of fever of doctors and nurses using a questionnaire.Main outcome measures: Prospective study: final diagnosis (viral, non- invasive bacterial disorders, invasive bacterial disorders), site of measurement and average temperature. Evaluation of theoretical knowledge: definition of fever, site of measurement, evaluation of the child’s clinical state, antipyretic drug choice.Results: A total of 114 children under 5 years of age were enrolled and 24 caregivers (12 doctors, 12 nurses, 90 of the staff) responded to the questionnaire. The results showed good consistency in theoretical knowledge, but an excessive fear about cerebral damage was also shown by doctors. This belief likely contributes to the transmission of fever phobia to parents. In contrast, analysis of children management showed that fever was often under-treated, especially by nurses and even more so by parents. Paracetamol remained the first-line antipyretic drug yet was often administered in insufficient doses. Non-steroidal anti-inflammatory drugs were seldom used, except by parents (16 of all the children). Contrary to literature, the favourite route of administration was the rectal one. Physical methods like sponging were largely used by nurses, despite the uncertainties in their real effectiveness and their known side-effects.Conclusion: Our study showed that the management of feverish children was globally correct in the Paediatric Emergency Department, but several improvement measures have been taken (e.g. tables of normal and abnormal ranges of temperature, recommended temperature measurement techniques, dosage regimen of antipyretic drugs, guidelines to parents), justifying the implementation of a pharmaceutical follow-up.  相似文献   
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