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11.
Estimates of chronic hepatitis B virus infection in Australia, 2000   总被引:1,自引:0,他引:1  
Objectives : To estimate the prevalence of chronic hepatitis B virus (HBV) infection in Australia and attributable proportions associated with specific demographic groups at higher risk of infection.
Methods : Two methods were used to estimate prevalence of HBV surface antigen (HBsAg): (1) Population-based: results of a national serosurvey using sera collected opportunistically from laboratories across Australia were used for 1–59 year olds, with the HBsAg prevalence for 50–59 years extrapolated to the population aged 60 years and over; (2) Risk group-based: estimates for selected high-risk groups (injecting drug users, homosexual men, Indigenous Australians and people born in high-prevalence countries), using source data from antenatal HBV screening in central Sydney, HBV prevalence studies, and estimates for low-risk groups (first-time blood donors) were combined proportionally to their representation in the population.
Results : Prevalence of HBsAg in the national serosurvey increased, with age, from 0.0% for 1–4 and 5–9 year olds to 1.3–1.8% for the 40–49 year age group. Australian population HBsAg prevalence based on minimum and adjusted estimates from this serosurvey were 91,500 (0.49%) and 163,000 (0.87%) infections, respectively. The risk group method estimated an Australian HBsAg prevalence of 88,000 infections (0.47%). Approximately 50% of people with chronic HBV infection were estimated to be immigrants from either South-East Asia (33.3%) or North-East Asia (16.2%).
Conclusion : The range of estimates for chronic HBV infection in Australia is broad, reflecting the uncertainty in source data. A national blood survey encompassing a large and representative population sample may help to provide more accurate estimates. A large proportion of people with chronic HBV infection are Asian born.  相似文献   
12.
Fusarium is a filamentous opportunistic pathogenic fungus responsible for superficial as well as invasive infection in immunocompromized hosts. Net state of immunosuppression and cytomegalovirus (CMV) infection appear to predispose to this disease which is life-threatening when disseminated. Though infections with Fusarium have been widely described in hematological malignancies and hematopoietic stem cell transplant cases, they have been reported to be rare in solid organ transplant recipients, are often localized and carry a favorable prognosis. We here describe a rare case of subcutaneous non-invasive infection with Fusarium in a renal allograft recipient two and half years after transplantation. Patient had a previous history of CMV infection along with multiple other recurrent co-infections. Diagnosis was based on culture of tissue specimens yielding Fusarium species. The infection had a protracted course with persistence of lesions after treatment with voriconazole alone, requiring a combination of complete surgical excision and therapy with the anti-fungal drug.  相似文献   
13.
Implementation of evidence-based practices (EBPs) is highly encouraged within mental health services. This single case study examines the process of an EBP implementation effort, guided by the National Implementation Research Network (NIRN) implementation model, from the perspective of behavioural healthcare managers in a child and youth mental health provider organization. Qualitative methods identified process themes emerging over 3 years of an organizational change process that support and refine the NIRN model. Dedicated management oversight and implementation teams are essential for EBP implementation; practice leads and practice coaches are useful implementation innovations; and organizations seeking to implement several EBPs simultaneously must guard against organizational absorptive capacity. These findings can guide EBP implementation in child and youth behavioural healthcare.  相似文献   
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OBJECTIVE:

to test a theoretical model based on the Parent-Based Expansion of the Theory of Planned Behavior examining relation between selected parental, teenager and cultural variables and Latino teenagers'' intentions to engage in sexual behavior.

METHOD:

a cross-sectional correlational design based on a secondary data analysis of 130 Latino parent and teenager dyads.

RESULTS:

regression and path analysis procedures were used to test seven hypotheses and the results demonstrated partial support for the model. Parent familism and knowledge about sex were significantly associated with parents'' attitudes toward sexual communication with their teenagers. Parent Latino acculturation was negatively associated with parents'' self-efficacy toward sexual communication with their teenagers and positevely associated with parents'' subjective norms toward sexual communication with their teenagers. Teenager knowledge about sex was significantly associated with higher levels of teenagers'' attitudes and subjective norms about sexual communication with parents. Only the predictor of teenagers'' attitudes toward having sex in the next 3 months was significantly associated with teenagers'' intentions to have sex in the next 3 months.

CONCLUSION:

the results of this study provide important information to guide future research that can inform development of interventions to prevent risky teenager sexual behavior among Latinos.  相似文献   
17.

Background

Current approaches to chemical screening, prioritization, and assessment are being reenvisioned, driven by innovations in chemical safety testing, new chemical regulations, and demand for information on human and environmental impacts of chemicals. To conceptualize these changes through the lens of a prevalent disease, the Breast Cancer and Chemicals Policy project convened an interdisciplinary expert panel to investigate methods for identifying chemicals that may increase breast cancer risk.

Methods

Based on a review of current evidence, the panel identified key biological processes whose perturbation may alter breast cancer risk. We identified corresponding assays to develop the Hazard Identification Approach for Breast Carcinogens (HIA-BC), a method for detecting chemicals that may raise breast cancer risk. Finally, we conducted a literature-based pilot test of the HIA-BC.

Results

The HIA-BC identifies assays capable of detecting alterations to biological processes relevant to breast cancer, including cellular and molecular events, tissue changes, and factors that alter susceptibility. In the pilot test of the HIA-BC, chemicals associated with breast cancer all demonstrated genotoxic or endocrine activity, but not necessarily both. Significant data gaps persist.

Conclusions

This approach could inform the development of toxicity testing that targets mechanisms relevant to breast cancer, providing a basis for identifying safer chemicals. The study identified important end points not currently evaluated by federal testing programs, including altered mammary gland development, Her2 activation, progesterone receptor activity, prolactin effects, and aspects of estrogen receptor β activity. This approach could be extended to identify the biological processes and screening methods relevant for other common diseases.

Citation

Schwarzman MR, Ackerman JM, Dairkee SH, Fenton SE, Johnson D, Navarro KM, Osborne G, Rudel RA, Solomon GM, Zeise L, Janssen S. 2015. Screening for chemical contributions to breast cancer risk: a case study for chemical safety evaluation. Environ Health Perspect 123:1255–1264; http://dx.doi.org/10.1289/ehp.1408337  相似文献   
18.
Purpose: We sought to identify patient-reported barriers and facilitators to healthy eating and physical activity among patients before or after knee arthroplasty.

Materials and methods: Twenty patients with knee osteoarthritis aged 40–79 years who had knee arthroplasty surgery scheduled or completed within 3 months were interviewed. Interview topics included perceived barriers and facilitators to healthy eating and activity before or after surgery. Interviews were coded and analyzed using constant comparative analysis.

Results: Interviews were completed with 11 pre-operative (67.1?±?7.6?years, 45.5% female, BMI 31.2?±?6.3) and nine post-operative patients (61.7?±?11.7 years, 44.4% female, BMI 30.2?±?4.7?kg/m2). The most commonly identified personal barriers to healthy eating identified were desire for high-fat/high-calorie foods, managing overconsumption and mood. Factors related to planning, portion control and motivation to improve health were identified as healthy eating facilitators. Identified personal barriers for activity included pain, physical limitations and lack of motivation, whereas facilitators included having motivation to improve knee symptoms/outcomes, personal commitment to activity and monitoring activity levels.

Conclusion: Identifying specific eating and activity barriers and facilitators, such as mood and motivation to improve outcomes, provides critical insight from the patient perspective, which will aid in developing weight management programs during rehabilitation for knee arthroplasty patients.
  • Implications for rehabilitation
  • This study provides insight into the identified barriers and facilitators to healthy eating and physical activity in knee arthroplasty patients, both before and after surgery.

  • Intrapersonal barriers that may hinder engagement in physical activity and rehabilitation include pain, physical limitations and lack of motivation; factors that may help to improve activity and the rehabilitation process include being motivated to improve knee outcomes, having a personal commitment to activity and tracking activity levels.

  • Barriers that may interfere with healthy eating behaviors and knee arthroplasty rehabilitation include the desire for high-fat/high-calorie foods, overeating and mood; whereas planning and portion control may help to facilitate healthy eating.

  • Understanding barriers and facilitators to healthy eating and physical activity can help guide rehabilitation professionals with their discussions on weight management with patients who had or are contemplating knee arthroplasty.

  相似文献   
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Background

Intervertebral disc degeneration is a common condition with few inexpensive and effective modes of treatment, but current investigations seek to clarify the underlying process and offer new treatment options. It will be important for physicians to understand the molecular basis for the pathology and how it translates to developing clinical treatments for disc degeneration. In this review, we sought to summarize for clinicians what is known about the molecular processes that causes disc degeneration.

Results

A healthy disc requires maintenance of a homeostatic environment, and when disrupted, a catabolic cascade of events occurs on a molecular level resulting in upregulation of proinflammatory cytokines, increased degradative enzymes, and a loss of matrix proteins. This promotes degenerative changes and occasional neurovascular ingrowth potentially contributing to the development of pain. Research demonstrates the molecular changes underlying the harmful effects of aging, smoking, and obesity seen clinically while demonstrating the variable influence of exercise. Finally, oral medications, supplements, biologic treatments, gene therapy, and stem cells hold great promise but require cautious application until their safety profiles are better outlined.

Conclusions

Intervertebral disc degeneration occurs where there is a loss of homeostatic balance with a predominantly catabolic metabolic profile. A basic understanding of the molecular changes occurring in the degenerating disc is important for practicing clinicians because it may help them to inform patients to alter lifestyle choices, identify beneficial or harmful supplements, or offer new biologic, genetic, or stem cell therapies.  相似文献   
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