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David Wood

Publications and source records attributed to David Wood.

44 records · Page 3Linked to original sources

Effect of child and family poverty on child health in the United States.

Poverty has been described as an economic state that does not allow for the provision of basic family and child needs, such as adequate food, clothing, and housing. However, the debate about the effects of poverty on the growth, development, and health of children is as much involved with the culture or general context of poverty as it is with the economics of poverty. This culture of poverty is in part mediated through environmental deprivations, such as failing schools, gangs, drugs, violence, and struggling families. Heclo(1) described this sociocultural and environmental dimension of poverty as "a condition of misery, hopelessness, and dependency." The subject of this article is to review the literature on the effects of poverty on US children as mediated through economic, ecologic, and family influences.

Adolescent↗

Case report: Survival after deliberate strychnine self-poisoning, with toxicokinetic data.

INTRODUCTION: Strychnine poisoning is uncommon, and in most severe cases, the patient dies before reaching hospital. The management of strychnine poisoning is well documented, although there are few data on the kinetics of elimination of strychnine after overdose. CASE REPORT: A 42-year-old man presented shortly after ingestion of an unknown quantity of strychnine powder. After a respiratory arrest, with intensive supportive management requiring admission to an intensive care unit, he survived. Eight serum samples were taken over the first 5 days and analysed subsequently for strychnine concentrations. RESULTS: The initial concentration at 1.5 hours after ingestion was 4.73 mg/l, falling to 0.38 mg/l at 74 hours postingestion. Serum concentrations followed a monoexponential elimination curve with a calculated elimination half-life of 12 hours. DISCUSSION AND CONCLUSION: Strychnine poisoning presents with classical features, and with early diagnosis and supportive management, the patient can survive. The initial serum concentration of 4.73 mg/l is the highest reported concentration in a patient who has survived. Previous reports of the elimination half-life have suggested it is between 10 and 16 hours, which conforms to the elimination data in our case.

Adult↗

Vaccine quality--can a single standard be defined?

To analyze the current global situation with respect to vaccine quality and to monitor progress in attaining it, it is first necessary to define what this means. While acknowledging that manufacturers are responsible for the quality of the vaccines they produce, World Health Organization (WHO) proposes a definition for "vaccines of assured quality" which depends on the existence of a competent and fully functional regulatory authority as assessed by an external expert team using widely agreed indicators to regulate the product. A vaccine of assured quality is defined as one that consistently meets appropriate levels of purity, potency, safety and efficacy as judged through an independent review system competent to take an evidence-based decision on the product for a specified population in a specific context. Such a review system would make use of all available information, such as licensing dossiers, surveillance of field performance, lot-by-lot scrutiny, appropriate laboratory testing, cGMP inspection of manufacturers, and evaluation of clinical trials, generally assumed by a fully functional regulatory authority. This definition implies that, faced with the same risk/benefit, any competent group would come to the same decision. The definition also indicates clear pathways to improve vaccine quality by strengthening national regulatory authorities and WHO is actively engaged in this task. By insisting on competent regulatory oversight, while recognizing the role of risk analysis in the selection of vaccines for use, WHO strongly reiterates the need for a single standard of quality. Only vaccine of assured quality should be considered for use in national immunization programs on the basis of the risk/benefit ratio for the particular population.

Drug and Narcotic Control↗

Development of an agricultural job-exposure matrix for British Columbia, Canada.

Farmers in British Columbia (BC), Canada have been shown to have unexplained elevated proportional mortality rates for several cancers. Because agricultural exposures have never been documented systematically in BC, a quantitative agricultural Job-exposure matrix (JEM) was developed containing exposure assessments from 1950 to 1998. This JEM was developed to document historical exposures and to facilitate future epidemiological studies. Available information regarding BC farming practices was compiled and checklists of potential exposures were produced for each crop. Exposures identified included chemical, biological, and physical agents. Interviews with farmers and agricultural experts were conducted using the checklists as a starting point. This allowed the creation of an initial or 'potential' JEM based on three axes: exposure agent, 'type of work' and time. The 'type of work' axis was determined by combining several variables: region, crop, job title and task. This allowed for a complete description of exposures. Exposure assessments were made quantitatively, where data allowed, or by a dichotomous variable (exposed/unexposed). Quantitative calculations were divided into re-entry and application scenarios. 'Re-entry' exposures were quantified using a standard exposure model with some modification while application exposure estimates were derived using data from the North American Pesticide Handlers Exposure Database (PHED). As expected, exposures differed between crops and job titles both quantitatively and qualitatively. Of the 290 agents included in the exposure axis; 180 were pesticides. Over 3000 estimates of exposure were conducted; 50% of these were quantitative. Each quantitative estimate was at the daily absorbed dose level. Exposure estimates were then rated as high, medium, or low based on comparing them with their respective oral chemical reference dose (RfD) or Acceptable Daily Intake (ADI). This data was mainly obtained from the US Environmental Protection Agency (EPA) Integrated Risk Information System database. Of the quantitative estimates, 74% were rated as low (< 100%) and only 10% were rated as high (>500%). The JEM resulting from this study fills a void concerning exposures for BC farmers and farm workers. While only limited validation of assessments were possible, this JEM can serve as a benchmark for future studies. Preliminary analysis at the BC Cancer Agency (BCCA) using the JEM with prostate cancer records from a large cancer and occupation study/survey has already shown promising results. Development of this JEM provides a useful model for developing historical quantitative exposure estimates where is very little documented information available.

Agricultural Workers' Diseases↗

Conserved response regulator CtrA and IHF binding sites in the alpha-proteobacteria Caulobacter crescentus and Rickettsia prowazekii chromosomal replication origins.

CzcR is the Rickettsia prowazekii homolog of the Caulobacter crescentus global response regulator CtrA. CzcR expression partially compensates for developmental defects in ctrA mutant C. crescentus cells, and CzcR binds to all five CtrA binding sites in the C. crescentus replication origin. Conversely, CtrA binds to five similar sites in the putative R. prowazekii replication origin (oriRp). Also, Escherichia coli IHF protein binds over a central CtrA binding site in oriRp. Therefore, CtrA and IHF regulatory proteins have similar binding patterns in both replication origins, and we propose that CzcR is a global cell cycle regulator in R. prowazekii.

Bacterial Proteins↗

A walk in the patients' shoes: a step toward competency development in systems-based practice.

OBJECTIVES: To implement and evaluate the effectiveness of scenario-based learning as a method for teaching systems-based practice to pediatric residents. METHODS: Twelve pediatric residents at the University of Florida/Jacksonville participated in an active learning scenario experience during their 1-month community pediatrics block rotation from January 2003 to April 2004. A scenario, developed in partnership with community-based organizations, required the residents to assume the role of a parent faced with multiproblem life situations requiring skills in prioritizing problems and identifying and accessing community resources to address them. Residents documented their assessment of the experience as they went through it by making entries into a learning portfolio and at the end of the experience through written evaluations and exit interviews. A case study design was used to assess resident-perceived impact of this experience. Qualitative methods were used to analyze data from resident portfolio entries, resident written evaluation surveys, and resident exit interviews. RESULTS: Five themes, some of which reflect competencies in systems-based practice, emerged from the data: development of empathy and compassion, increased understanding of the barriers facing patients and families, increased appreciation of social determinants of health, self-perceived increased ability to serve patients, and advantages of active learning. CONCLUSIONS: Active learning experiences that simulate patient situations can be incorporated into community pediatrics training for residents, increasing perceived competence in systems-based practice.

Attitude of Health Personnel↗

The development, validation, and testing of a health outcomes burn questionnaire for infants and children 5 years of age and younger: American Burn Association/Shriners Hospitals for Children.

The 12-member American Burn Association/Shriners Hospitals for Children Outcomes Task Force was charged with developing a health outcomes questionnaire for use in children 5 years of age and younger that was clinically based and valid. A 55-item form was tested using a cross-sectional design on the basis of a range of 184 infants and children between 0 and 5 years of age at 8 burn centers, nationally. A total of 131 subjects completed a follow-up health outcomes questionnaire 6 months after the baseline assessment. A comparison group of 285 normal nonburn children was also obtained. Internal consistency reliability of the scales ranged from 0.74 to 0.94. Tests of clinical validity were significant in the hypothesized direction for the majority of scales for length of hospital stay, duration since the burn, percent of body surface area burned, overall clinician assessment of severity of burn injury, and number of comorbidities. The criterion validity of the instrument was supported using the Child Developmental Inventories for Burn Children in early childhood and preschool stages of development comparing normal vs abnormal children. The instrument was sensitive to changes over time following a clinical course observed by physicians in practice. The Health Outcomes Burn Questionnaire for Infants and Children 5 years of age and younger is a clinically based reliable and valid assessment tool that is sensitive to change over time for assessing burn outcomes in this age group.

Burns↗