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PubMedDate not supplied

Factors explaining lack of response to heel stick in preterm newborns.

OBJECTIVE: To determine factors explaining lack of response by preterm newborns to heel stick for blood sampling. DESIGN: A cross-sectional design based on secondary analysis of the control session of a randomized crossover design. SETTING: Four Level III neonatal intensive-care units of university teaching hospitals. PARTICIPANTS: 120 preterm newborns with an average age of 28 weeks postconceptional age. INTERVENTION: 24 newborns who showed a "no change" response according the Premature Infant Pain Profile were compared to the remaining 96 newborns who had shown a pain response. MAIN OUTCOME MEASURES: Age (postconceptional age at birth, postnatal age at study), Apgar score at 5 minutes, severity of illness, sex, race, wake/sleep state, previous study sessions, total number of painful procedures since birth, and time since last painful procedure. RESULTS: After stepwise logistic regression analysis the variables remaining in the final model that explained the difference between the groups were postnatal age at time of study, postconceptional age at birth, time since last painful procedure, and wake/sleep state. CONCLUSIONS: Newborns who were younger, asleep, and had undergone a painful event more recently were less likely to demonstrate behavioral and physiologic indicators of pain.

Age Factors↗
PubMedDate not supplied

A pilot study on the effects of aquatic exercises on discomforts of pregnancy.

OBJECTIVES: To estimate the impact of an aquatic exercise program on perception of body image, participation in health-promoting behaviors, barriers to health-promoting participation, level of physical discomfort, and mobility. DESIGN: A two-group, quasi-experimental, pretest/posttest design. SAMPLE AND SETTING: A convenience sample of 40 nonexercising pregnant women who were at least 19 weeks gestation were recruited. Sixty percent of the sample was African American. Participants self-selected assignment to either the exercise or nonexercise group. Both groups completed self-report measures and underwent a mobility assessment. The exercise group participated in a 60-minute, 6-week aquatic exercise program three sessions per week. The control group was instructed to continue their normal activities of daily living. RESULTS: Women who had participated in the aquatic exercise program reported significantly less physical discomfort, improved mobility, and improved body image and health-promoting behaviors as compared to control subjects. CONCLUSIONS: Aquatic exercise during pregnancy may enhance physical functioning, decreasing maternal discomfort, improving maternal body image, and improving health-promoting behaviors.

Activities of Daily Living↗
PubMed1994

Increased rates of depression: update of epidemiological findings and analytical problems.

The evidence for an increased incidence of rates of depressive conditions, defined as depressed mood, depressive syndromes or depressive disorders, is reviewed. Findings from prospective studies, family genetic studies, community surveys, repeated cross-sectional surveys, admission data and suicide statistics are summarized. Methodological problems and difficulties in the analysis and interpretation of these results are then summarized. Because converging results from studies conducted with various designs, sampling and measurement strategies are convergent, it is concluded that the increase over time of depressive phenomena is a plausible finding. However, its magnitude remains unknown and is probably smaller than sometimes claimed. Furthermore, studies have failed to demonstrate that the increase in rates was specific to depressive conditions. Finally, it is noted that these epidemiological enquiries have failed to provide cues on the possible mechanisms underlying these secular changes.

Adolescent↗
PubMed2006

Clinical outcome in bipolar disorder in a community-based follow-up study in Butajira, Ethiopia.

OBJECTIVE: To determine the clinical outcome of bipolar disorder in a developing country setup. METHOD: After assessing 68 378 individuals, aged 15-49 years, in a double-sampling design in a rural community in Ethiopia, 312 patients with bipolar disorder were prospectively monitored with symptom rating scales and clinically for an average of 2.5 years. RESULTS: Overall, 65.9% of the cohort experienced a relapse--47.8% manic, 44.3% depressive and 7.7% mixed episodes--and 31.1% had persistent illness. Female gender predicted depressive relapse, while male gender predicted manic relapse. Being on psychotropic medication was associated with remission. CONCLUSION: This large community-based study confirms the relapsing nature of bipolar disorder and a tendency for chronicity. This may be partly because of lack of appropriate interventions in this setting; however, it may also indicate the underlying severity of the disorder irrespective of setting.

Adolescent↗
PubMed2004

Perception of general and oral health in White and African American adults: assessing the effect of neighborhood socioeconomic conditions.

OBJECTIVES: This study investigates the independent and joint effects of family income and neighborhood socioeconomic status (SES) on general health and oral health before and after controlling for traditional risk factors in a representative sample of adults aged 18+ years residing in the Detroit tri-county area, Michigan. METHODS: Individuals data were obtained through interviews, while neighborhood data came from the 1990 US Census. SUDAAN was used to accommodate the complex sampling design and correlation of outcomes within the same neighborhoods. RESULTS: Whites in disadvantaged neighborhoods were four times more likely to rate their oral health as fair or poor [odds ratio (OR): 4.0; 95% confidence intervals (CI): 1.6-10.3] than their counterparts in advantaged neighborhoods. When evaluating the joint effects of family income and neighborhood SES, low-income Whites in disadvantaged neighborhoods were six times more likely to rate their oral health as fair or poor (OR: 6.4; 95% CI: 1.6-26.5) than their high-income counterparts in advantaged neighborhoods. The odds of rating general health as fair or poor was six times greater in low-income African Americans in disadvantaged neighborhoods (OR: 6.1; 95% CI: 1.6-23.8) than high-income African Americans in advantaged neighborhoods. Similarly, low-income African Americans in disadvantaged neighborhoods were almost three times (OR: 2.8; 95% CI: 1.0-8.1) more likely to rate their oral health as fair/poor than high-income African Americans in advantaged neighborhoods. CONCLUSIONS: SES conditions at the neighborhood-level, independently or jointly with individual-level income, appear to be important in evaluating racial/ethnic differences in self-rated oral health. Neighborhood conditions could tap into constructs not captured by individual-level variables on self-rated oral health.

Adolescent↗
PubMed1997

Epidemiology of HIV-related oral manifestations in women: a review.

OBJECTIVE: (1) To assess the extent of knowledge acquired since 1981 on the epidemiology of HIV-related oral manifestations in women; (2) to determine if these findings differ by gender; and (3) to assess the needs and direction for future epidemiologic research on oral disease and HIV infection in women in relation to men. DATA IDENTIFICATION: A computer-assisted search was conducted to identify epidemiologic studies reporting the frequency of various oral conditions in HIV-infected women. Studies on periodontal disease as manifestation of HIV infection were not included. DATA EXTRACTION: Methods used in the retrieved articles were reviewed with respect to target population, study design, sampling scheme, outcomes, measurements and statistical issues. Results were summarized in relation to oral findings in HIV-infected men. RESULTS OF DATA SYNTHESIS: Most studies were prospective, and sample selection was non-random. Studies differed with respect to geographic location, risk category for HIV transmission, and stage of HIV disease. Despite these differences, oral lesions were found in at least 15% of HIV-infected women, and the most common oral lesion in all studies was candidiasis. Women differed from men with respect to the prevalence of hairy leukoplakia and Kaposi's sarcoma (KS) both of which were significantly less common in women. CONCLUSION: Future epidemiologic studies should be directed at identifying cofactors involved in addition to Epstein-Barr virus (EBV) in the development of hairy leukoplakia, and in addition to KS herpes virus (KSHV) in the occurrence of KS.

AIDS-Related Opportunistic Infections↗
PubMed2004

Abnormal craniofacial development and expression patterns of extracellular matrix components in transgenic Del1 mice harboring a deletion mutation in the type II collagen gene.

OBJECTIVE: To analyze the effect of a type II collagen mutation on craniofacial development in transgenic Del1 mice. DESIGN: Samples from homozygous (+/+) and heterozygous (+/-) transgenic Del1 mice harboring mutations in the type II collagen gene as well as non-transgenic (-/-) littermates were collected at days 12.5, 14.5, 16.5 and 18.5 of gestation. The cartilaginous and bony elements of the craniofacial skeleton were analyzed after staining with alcian blue, alizarin red S and von Kossa. The expression patterns of type II, IX and X collagens and aggrecan were analyzed by immunohistochemistry and in situ hybridization. RESULTS: Several abnormalities were observed in the craniofacial skeleton of transgenic Del1 mice. These include an overall retardation of chondrogenesis and osteogenesis in Del1 +/+ mice, and to a lesser extent also in Del1+/- mice. Characteristic findings in Del1 +/+ mice included a reduced anterioposterior length, a smaller size of the mandible, a palatal cleft and a downward bending snout. We also detected retarded ossification of calvarial bones in Del1 +/+ and +/- mice when compared with Del1 -/- mice. A surprising finding was the presence of both type II and X collagens and their mRNAs in the periosteum of the cranial base. CONCLUSION: The present study confirms the important role of type II collagen mutation in craniofacial development and growth. In addition to affecting endochondral ossification, the type II collagen mutation also disturbs intramembranous ossification in the developing craniofacial skeleton.

Animals↗
PubMed1985

Psychological factors in cost-benefit analysis of somatic prevention. A study of the psychological effects of neonatal screening for alpha 1-antitrypsin deficiency.

Nation-wide neonatal screening for alpha 1-antitrypsin deficiency (ATD) in Sweden was discontinued due to observations that identification of ATD in newborns seemed in some cases to have negative psychological effects on the parents and the parent-child relationship. A multifaceted study was developed to investigate systematically the psychological and psychosocial consequences of the identification of ATD in the neonatal period, as studied five to seven years after it took place. The study's basic goals, hypotheses, design, samples and methods are described.

Attitude to Health↗
PubMed2005

Delivery complications associated with prenatal care access for Medicaid-insured mothers in rural and urban hospitals.

CONTEXT: Pregnancy complications affect many women. It is likely that some complications can be avoided through routine primary and prenatal care of reasonable quality. PURPOSE: The authors examined access to health care during pregnancy for mothers insured by Medicaid. The access indicator is potentially avoidable maternity complications (PAMCs). Potentially avoidable maternity complications are often preventable through routine prenatal care, such as infection screening and treatment. The authors examined the risks of potentially avoidable maternity complications among rural and urban hospital deliveries for groups of mothers defined by race or ethnicity. METHODS: Data are from the year 2000 Nationwide Inpatient Sample (NIS). The stratified sample represents all discharges from 20.5% of community hospitals in the United States. The Nationwide Inpatient Sample identifies hospital locations, but not patients' areas of residence. Analyses, which accounted for the sample design, included calculation of potentially avoidable maternity complication rates by race or ethnicity, chi2, t tests, and multivariate logistic regression. FINDINGS: Within groups defined by race or ethnicity, unadjusted rates for potentially avoidable maternity complications did not differ significantly by hospital location. Holding other factors constant, potentially avoidable maternity complications were less common in rural hospitals than in urban hospitals (odds ratio, 0.78; CI, 0.62 to 0.99). In rural hospitals, African Americans had notably higher risk for potentially avoidable maternity complications than did non-Hispanic whites (odds ratio, 1.72; CI, 1.26 to 2.36). In urban hospitals, risk of potentially avoidable maternity complications was not significantly higher for African Americans. Hispanics and Asians had notably lower risks of potentially avoidable maternity complications in urban hospitals than did non-Hispanic whites. CONCLUSIONS: Providers and policymakers should work to reduce the risks of potentially avoidable maternity complications for African American women in rural areas who are insured by Medicaid.

Adolescent↗
PubMed2000

Application of PCR assays to determine the genotype of Babesia bovis parasites isolated from cattle with clinical babesiosis soon after vaccination against tick fever.

OBJECTIVE: To demonstrate the value of PCR assays to determine the genotypes of Babesia bovis in cattle with clinical signs of babesiosis within 3 weeks after vaccination against tick fever. DESIGN: Samples from 5 cases of babesiosis in cattle soon after vaccination against tick fever were analysed in two PCR assays. PROCEDURE: Parasite DNA was purified from blood taken from cattle with signs of babesiosis within 3 weeks of vaccination against tick fever. DNA was also prepared from the tissues of animals that died of babesiosis. Two PCR assays that amplify repeat sequences of DNA within the B bovis genes, Bv80 and BvVA1, were used to differentiate the genotypes of field isolates and vaccine strains of B bovis. RESULTS: One of the five cases of babesiosis was found to be caused by a vaccine strain, but PCR analyses showed that the predominant isolate in the other four cases was not the vaccine strain. CONCLUSIONS: PCR assays on the DNA of B bovis obtained from the blood or tissues of cattle clinically affected with tick fever within 3 weeks after vaccination are useful to distinguish between vaccine strains and field isolates as the source of infection.

Animals↗
PubMed2002

Confirmation of the existence of two distinct genetic groups of infectious bursal disease virus in Australia.

OBJECTIVE: To characterise infectious bursal disease viruses (IBDVs) prevalent at major commercial sites throughout Australia and to compare the nucleic acid sequences of local strains of IBDV with those of characterised overseas strains. DESIGN: Samples of bursae were collected from 20 broiler farms that belonged to different poultry companies in New South Wales (NSW), Queensland (Qld), Victoria (Vic), Westem (WA) and South Australia (SA). METHOD: Bursae were collected from broilers between 24 and 35 days of age. Bursal tissue was homogenised and tested for the presence of IBDV antigen using four monoclonal antibodies (Mabs) which detect antigenic variation in IBDV strains. The nucleotide sequences of the hypervariable region (HVR) within the VP2 gene of IBDVs was determined and the deduced amino acid sequences compared with three vaccine strains and six previously characterised Australian IBDV strains. The deduced amino acid sequences were also compared with the published amino acid sequences of overseas strains. The phylogenetic relationships between Australian strains and overseas strains were then determined. RESULTS: IBDV was detected in birds from 14 out of 20 farms sampled. Typing with four Mabs showed that all viruses from Vic (6) and SA (10) were antigenic variants, whereas all viruses from NSW (29), Qld (4) and WA (5) were classical-like strains. Nucleotide sequencing of one sample from each of the 14 farms on which IBDV was detected confirmed results obtained with Mabs. The amino acid sequences of all Australian viruses differed from the amino acid sequences of foreign IBDV strains. Phylogenetic analysis showed that Australian IBDV viruses belonged to two distinct genetic groups. Very virulent (vv) IBDV strains belonged to a third genetic group, and overseas classical and variant strains belonged to a fourth genetic group. CONCLUSIONS: The results confirmed previous findings that there are two groups of IBDV strains circulating in commercial broilers in Australia. The majority are classical-like strains that are antigenically and genetically similar to vaccine strains 002/73 and V877. These classical strains were prevalent in broilers in three states, NSW, Qld and WA. The second group of strains are antigenic variants that were only found in broilers in two states, Vic and SA. All Australian IBDVs characterised to date are genetically distinct and can be differentiated from all other overseas strains. This enables identification of incursion of any exotic strain into Australian poultry, be it classical, US variant or wIBDV strains.

Amino Acid Sequence↗
PubMed2004

Detection of subgroup J avian leukosis virus infection in Australian meat-type chickens.

OBJECTIVE: To determine the extent of avian leukosis virus subgroup J (ALV-J) infection in Australian broiler breeder flocks, using virus isolation and molecular biological detection. Any resultant ALV-J viral isolates to be characterised by neutralisation cross testing in order to determine antigenic relationships to overseas isolates of ALV-J. STUDY DESIGN: Samples of blood, feather pulp, albumen and tumours were obtained from broiler breeder flocks which represented four genetic strains of meat chickens being grown in Victoria, South Australia, NSW and Queensland. Dead and ailing birds were necropsied on farm and samples were collected for microscopic and virological examinations. Virus isolation was carried out in C/O and DF-1 CEF cultures and ALV group specific antigen was detected in culture lysates using AC-ELISA. Micro-neutralisation assay was used for antigenic characterisation of selected isolates. Genomic DNA was isolated from cultured cells, tumours and feather pulp. ALV-J envelope sequences were amplified by PCR using specific ALV-J primers while antibodies against ALV-J were detected by ELISA. RESULTS: A total of 62 ALV-J isolates were recovered and confirmed by PCR from 15 (31.3%) of 48 breeder flocks tested. Antibody to ALV-J was detected in 20 (47.6%) of the 42 flocks tested. Characteristic lesions of myeloid leukosis caused by ALV-J were found in affected flocks. The gross pathological lesions were characterised by skeletal myelocytomas located on the inner sternum and ribs, neoplastic enlargement of the liver, and in some cases gross tumour involvement of the spleen, kidney, trachea, skeletal muscles, bone marrow, skin and gonads. Microscopically, the tumours consisted of immature granulated myelocytes, and were present as focal or diffuse infiltrations in the affected organs. Virus micro-neutralisation assays demonstrated antigenic variation among Australian isolates and to overseas strains of ALV-J. CONCLUSION: ALV-J infection was prevalent in Australian broiler breeder flocks during 2001 to 2003. Australian isolates of ALV-J show a degree of antigenic variation when compared to overseas isolates.

Animals↗
PubMed2003

The New York State Minority Health Survey: determinants of oral health care utilization.

OBJECTIVES: To determine the factors associated with visits to a dentist and more specifically the role of dental insurance coverage and to explore the reasons for not visiting a dentist among minorities in New York State. METHODS: The Minority Health Survey was a one-time, statewide, random digit-dialed telephone survey. We drew a directed acyclic graph (DAG) of the potential determinants of oral health care utilization for our population of interest and modeled the independent variables as determinants of oral health care utilization. The data for this study were analyzed in SUDAAN using appropriate weights and variance adjustments that accounted for the complex sampling design. Hence, this report is generalizable to the New York State adult "minority" population. RESULTS: About 63 percent respondents had visited a dentist in the past one year. Having dental insurance (adjusted odds ratio [adj OR]=2.5), having more than high school education (adj OR=1.9), being younger (adj OR=2.3 for 18-25 years vs age 40 years or older), being married (adj OR=1.7), being dentate (adj OR=0.3 for edentulousness), and having higher income (adj OR=0.5 for middle vs high income) were significantly associated with having visited a dentist in the past year. Cost and awareness-related factors were the most common reasons for not visiting a dentist. Most of the year 2000 oral health objectives measurable in this survey were not met. CONCLUSION: Increasing dental insurance coverage and increasing awareness about oral health care would be the two biggest factors in meeting the goals of year 2010.

Adolescent↗
PubMed2001

Iron and colorectal cancer risk: human studies.

Some reports have associated iron with cancer risk, particularly of the colorectum. This review will focus on the human studies that have investigated this association. Comparative studies were sought in which people with and without colorectal neoplastic lesions, either cancers or adenomatous polyps, were assessed for iron exposure. Iron exposure variables included dietary iron intake, iron vitamin supplementation, body iron stores as measured by ferritin or transferrin saturation, and gene status for hereditary hemochromatosis. Medline was searched for published reports using the key words iron, cancer, colon, rectum, ferritin, transferrin, and hemochromatosis. In addition, the Cochrane Library was searched for relevant studies and several authors were contacted to investigate their awareness of unpublished studies. Studies were categorized by study design and ranked for quality of innovation in design, sample size, and thoroughness of iron status ascertainment. Thirty-three studies were reviewed in 26 publications. Of the larger studies, approximately three-quarters supported the association of iron, in all three strata of exposure, with colorectal neoplasia risk. Because iron is broadly supplemented in the American diet, the benefits of iron supplementation need to be measured against the long-term risks of increased iron exposure, one of which may be increased risk of colorectal cancer.

Colorectal Neoplasms↗
PubMedDate not supplied

Oral health care in US nursing homes, 1995.

In 1993, nursing home care was a $70 billion industry. Since oral diseases are intertwined with declining health, it is important to achieve a better understanding of oral health care in nursing homes. The purpose of this paper is to present basic information regarding the nature of dental care from the 1995 US National Nursing Home Survey. Data include general availability of dental services, a description of types of dentists' and dental hygienists' services, and numbers of full-time equivalent dentists and dental hygienists. SUDAAN software was used to adjust for the complex, multistage sample design. Of the estimated 16,700 nursing homes in the contiguous US in 1995, between 14,000 and 15,000 offered some level of dental services. About 15,600 nursing homes provided assistance for oral hygiene, while some 7720 nursing homes had dental hygienists' services available. Approximately 60% of nursing homes either did not have services of dentists at all, or had them only on call or only off-site. Availability of dental services varied by characteristics of nursing homes. Examination of the nature of dental care raises questions about whether the intent of the Federal standards for dental care in Medicare and Medicaid are really being met. As more elderly remain dentate, and as the oral comorbidities of chronic diseases become more recognized, appropriate oral health services for individuals in long-term care settings likely will increase as public health issues.

Administrative Personnel↗
PubMed1982

HLA and ophthalmic disease associations: a critical review and improved method for statistical analysis.

A critical review of published ophthalmic histocompatibility antigen association studies found numerous conflicting or ambiguous reports. Methodologic errors that could account for these discrepancies were categorized into 3 groups (1) arbitrary application of statistical methods to determine significance, (2) poor sampling design, and (3) variable disease definition. Multivariate analysis, not previously applied in this area provides a more powerful tool for assessing statistical significance. A computer program using this methodology for large studies is now available.

Computers↗
PubMed2002

Airway cooling and mucosal injury during cold weather exercise.

In human subjects that exercise strenuously in cold weather, there is evidence that hyperventilation with cold air leads to peripheral airway cooling, desiccation and mucosal injury. Our hypothesis was that hyperventilation with cold air can result in penetration of unconditioned air (air that is not completely warmed and humidified) into the peripheral airways of exercising horses, resulting in peripheral airway mucosal injury. To test this hypothesis, a thermister-tipped catheter was inserted through the midcervical trachea and advanced into a sublobar bronchus in three horses that cantered on a treadmill at 6.6 m/s while breathing cold (5 degrees C) air. The mean (+/- s.e.) intra-airway temperature during cantering was 33.3 +/- 0.4 degrees C, a value comparable to the bronchial lumen temperatures measured in man during maximal exercise while breathing subfreezing dry air. In a second experiment, 6 fit Thoroughbred racehorses with satisfactory performance were used to determine whether strenuous exercise in cold conditions can produce airway injury. Horses were assigned to Exercise (E) or Control (C) groups in a random crossover design. Samples of bronchoalveolar lavage fluid (BALF) in the E treatment were recovered within 30 min of galloping exercise in 4 degrees C, 100% relative humidity (E), while in C BALF samples were obtained when the horses had not performed any exercise for at least 48 h prior. Ciliated epithelial cells in BALF were higher in E than in the C treatment. Similar results have been found in human athletes and laboratory animal models of cold weather exercise. These results support the hypothesis that, similar to man, horses that exercise in cold weather experience peripheral airway mucosal injury due to the penetration of unconditioned air. Furthermore, these results suggest that airway cooling and desiccation may be a factor in airway inflammation commonly found in equine athletes.

Air↗
PubMed1991

Horizontal variation of bacterioplankton in the baltic sea.

Variations in the thymidine incorporation rate, bacterial abundance, and mean cell volumes in the surface water (0.5 m) of the Baltic Sea in spring and summer were compared in studies with different spatial scales (570 nautical miles [nmi] [ca. 1056 km], 220 nmi [ca. 407 km], 24 nmi [ca. 44 km], 12 nmi [ca. 22 km], and 200 m). The objective of the comparison was to investigate whether a single sample taken at one sampling point is representative enough for researchers to make generalizations about a larger water area. Bacterioplankton variation was connected more to seasonal characteristics than to the spatial scale of sampling. Variation was greater and more random in spring than in summer. The state variables (bacterial abundance and mean cell volume) varied less than the rate variable (thymidine incorporation). The results suggest that the sampling design for bacterioplankton studies in northern temperate seas should be planned primarily according to the season and that more stress should be put on rate variable measurements than on those of state variables.

Journal Article↗