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Detection of autoplaque-forming cells as a means for characterizing the state of reactivity of the child organism.

Counts of plaque-forming cells [PFC] in blood were determined by the method of N. N. Klemparskaya in 181 children aged 1 to 3 years living in an organized community. A raised level of autoantibody-producing cells was detected in 45% of the children. The causes responsible for this enhanced autoimmunization may have been different infectious diseases. On the basis of phenomenon of PFC count increase in the presence of penicillin in specimens in vitro, hypersensitivity to thi antibiotic in the absence of clinical manifestations of allergy was detected in 27% of children.

Allergens↗

Mammography outcomes in a practice setting by age: prognostic factors, sensitivity, and positive biopsy rate.

The separate unplanned analysis of women ages 40-49 in population-based randomized controlled trials has resulted in demonstration of statistically significant breast cancer mortality reduction due to screening mammography in only two of the individual trials, and in all such trials only through meta-analysis. Therefore, many researchers have utilized the surrogate endpoints of tumor size and axillary lymph node status to evaluate screening efficacy. For the present study, these endpoints were evaluated in an audit of 854 screen-detected cancers found in 147,125 mammographic examinations performed in women over 40 between 1988 and 1994 in a community practice setting. The concerns that mammography in the 40-49 group has a lower sensitivity and higher biopsy rate were also addressed. Median invasive tumor size and lymph node positivity were found to be equally small (1.0-1.1 cm and 13.5-12.2%, respectively), and the sensitivity and overall biopsy rate were found to be constant over all ages 40 and above. Positive biopsy rate (PBR) varied directly with increasing age, paralleling the measured cancer detection rate in each decade, with no abrupt change at age 50. We conclude that modern mammography in a community practice setting can successfully detect breast cancers with favorable prognostic factors and achieve constant sensitivity and acceptable PBRs in all women over 40. Our data also suggest that many of the large differences seen by inappropriately dividing data at age 50 decrease or disappear when analysis is performed by decade.

Adult↗

Isolation of broad-host-range replicons from marine sediment bacteria.

Naturally occurring plasmids isolated from heterotrophic bacterial isolates originating from coastal California marine sediments were characterized by analyzing their incompatibility and replication properties. Previously, we reported on the lack of DNA homology between plasmids from the culturable bacterial population of marine sediments and the replicon probes specific for a number of well-characterized incompatibility and replication groups (P. A. Sobecky, T. J. Mincer, M. C. Chang, and D. R. Helinski, Appl. Environ. Microbiol. 63:888-895, 1997). In the present study we isolated 1.8- to 2.3-kb fragments that contain functional replication origins from one relatively large (30-kb) and three small (<10-kb) naturally occurring plasmids present in different marine isolates. 16S rRNA sequence analyses indicated that the four plasmid-bearing marine isolates belonged to the alpha and gamma subclasses of the class Proteobacteria. Three of the marine sediment isolates are related to the gamma-3 subclass organisms Vibrio splendidus and Vibrio fischeri, while the fourth isolate may be related to Roseobacter litoralis. Sequence analysis of the plasmid replication regions revealed the presence of features common to replication origins of well-characterized plasmids from clinical bacterial isolates, suggesting that there may be similar mechanisms for plasmid replication initiation in the indigenous plasmids of gram-negative marine sediment bacteria. In addition to replication in Escherichia coli DH5alpha and C2110, the host ranges of the plasmid replicons, designated repSD41, repSD121, repSD164, and repSD172, extended to marine species belonging to the genera Achromobacter, Pseudomonas, Serratia, and Vibrio. While sequence analysis of repSD41 and repSD121 revealed considerable stretches of homology between the two fragments, these regions do not display incompatibility properties against each other. The replication origin repSD41 was detected in 5% of the culturable plasmid-bearing marine sediment bacterial isolates, whereas the replication origins repSD164 and repSD172 were not detected in any plasmid-bearing bacteria other than the parental isolates. Microbial community DNA extracted from samples collected in November 1995 and June 1997 and amplified by PCR yielded positive signals when they were hybridized with probes specific for repSD41 and repSD172 replication sequences. In contrast, replication sequences specific for repSD164 were not detected in the DNA extracted from marine sediment microbial communities.

Bacteria↗

Validating an asthma case detection instrument in a Head Start sample.

Although specific tests screen children in preschool programs for vision, hearing, and dental conditions, there are no published validated instruments to detect preschool-age children with asthma, one of the most common pediatric chronic conditions affecting children in economically disadvantaged communities of color. As part of an asthma education intervention, a 15-item Brief Respiratory Questionnaire (BRQ) was developed to detect children with probable asthma in Head Start and subsidized preschool settings in communities with high asthma prevalence and associated morbidity. Preschool personnel administered the BRQ to consenting parents of 419 enrolled children. Trained interviewers administered validation interviews (VALs) to parents of 149 case-positive children and 51 case-negative children. Three physicians independently assessed deidentified summaries of the VALs that captured responses about signs and symptoms of asthma, diagnosis and treatment, and use of medical services. The physicians' assessments of the summarized VALs were the validated standard to which the BRQ classifications were compared. A simple algorithm of 4 items was identified that can be administered and scored by nonmedical preschool personnel in less than 5 minutes. The chance-corrected agreement between these 4 items of the BRQ and the VAL was good: kappa, .73 (95% confidence interval, 0.62-0.84); specificity, 96%; sensitivity, 73%; and positive predictive value, 97%. The BRQ appears to be a valid instrument for detecting children with probable asthma in Head Start and other subsidized preschool settings in communities with high prevalence of asthma.

Allergens↗

Links between ammonia oxidizer species composition, functional diversity and nitrification kinetics in grassland soils.

Molecular approaches have revealed considerable diversity and uncultured novelty in natural prokaryotic populations, but not direct links between the new genotypes detected and ecosystem processes. Here we describe the influence of the structure of communities of ammonia-oxidizing bacteria on nitrogen cycling in microcosms containing natural and managed grasslands and amended with artificial sheep urine, a major factor determining local ammonia concentrations in these environments. Nitrification kinetics were assessed by analysis of changes in urea, ammonia, nitrite and nitrate concentrations and ammonia oxidizer communities were characterized by analysis of 16S rRNA genes amplified from extracted DNA using ammonia oxidizer-specific primers. In natural soils, ammonia oxidizer community structure determined the delay preceding nitrification, which depended on the relative abundance of two Nitrosospira clusters, termed 3a and 3b. In batch cultures, pure culture and enrichment culture representatives of Nitrosospira 3a were sensitive to high ammonia concentration, while Nitrosospira cluster 3b representatives and Nitrosomonas europaea were tolerant. Delays in nitrification occurred in natural soils dominated by Nitrosospira cluster 3a and resulted from the time required for growth of low concentrations of Nitrosospira cluster 3b. In microcosms dominated by Nitrosospira cluster 3b and Nitrosomonas, no substantial delays were observed. In managed soils, no delays in nitrification were detected, regardless of initial ammonia oxidizer community structure, most probably resulting from higher ammonia oxidizer cell concentrations. The data therefore demonstrate a direct link between bacterial community structure, physiological diversity and ecosystem function.

Ammonia↗

Expanding horizons in breast and prostate cancer prevention and early detection. The 1992 Samuel C. Harvey Lecture.

Breast cancer and prostate cancer, the most common cancers in American women and men, respectively, are major public health concerns. Investigations into the prevention and early detection of breast and prostate cancer include research on the potential impact of diet, particularly dietary fat, on breast cancer risk; the chemoprevention of breast cancer using tamoxifen and N-(4-hydroxyphenyl)retinamide(4-HPR); the importance of mammography in early detection of breast cancer; the potential of finasteride in preventing or retarding the progression of early-stage prostate cancer; and improved detection of prostate cancer by combining various screening modalities. The importance of transferring information gained though such research to the health care community cannot be overemphasized. Further, it is critical that cancer prevention and detection education be built into the curricula of leading medical and biomedical institutions. Education is key to developing a strong and vigorous cancer prevention and early detection research program.

Antineoplastic Agents↗

High prevalence of cagA and vacA seropositivity in asymptomatic Bangladeshi children with Helicobacter pylori infection.

AIM: To evaluate the prevalence of antibodies against two major markers of virulence of Helicobacter pylori--cytotoxin-associated gene A (cagA) and the vacuolating cytotoxin gene (vacA)--among children in a peri-urban community of Bangladesh, and to evaluate Western blot (WB) assay for detection of H. pylori infection diagnosed by 13C urea breath test (UBT) in such children. METHODS: One hundred and eighty-two children aged 18-60 mo, of the peri-urban community of Dhaka, were screened for H. pylori infection using UBT, and the serum samples were analysed for antibody against cagA and vacA by Western blot. RESULTS: The overall prevalence of H. pylori infection by 13C-urea breath test was 80%. The seroprevalence of cagA with or without vacA, vacA with and without cagA, and both cagA and vacA were 82%, 82% and 81%, respectively. Among children with a positive UBT, 95% were seropositive for both cagA and vacA, indicating that the products of these genes are frequently co-expressed in H. pylori infection in this community. The sensitivity, specificity, positive and negative predictive value of the Western blot test for H. pylori infections, compared to UBT, were 94%, 68%, 92% and 76%, respectively. CONCLUSION: Compared to UBT, Western blot test is reliable for the detection of H. pylori infection. The high seroprevalence of cagA- and vacA-positive virulent H. pylori strains in an asymptomatic paediatric population indicate that such strains are common in this population and may cause characteristic H. pylori infection in Bangladesh.

Antibodies, Bacterial↗

The Austin Doyle Lecture, High Blood Pressure Research Council of Australia. Renal disease as a metaphor: towards a more integrated view of aboriginal health.

1. The health of Aboriginal people in the Northern Territory of Australia is among the worst in the world, with mortality rates increased in every 'disease-specific' category and averaging overall approximately five-fold those of non-Aboriginal Australians. Health services, which in most regions are rudimentary, fragmented and under-resourced, have been slow to recognize and meet this challenge. However, the cost implications of an epidemic of renal failure have stimulated concern that broader mortality statistics could not. 2. In one high-risk Aboriginal community, we found that renal disease can be detected and its course chartered by a simple and reliable screening test. Renal disease arises out of a broad menu of risk factors that reflect poverty, disadvantage and accelerated lifestyle changes and its expression is progressively amplified with the simultaneous operation of more than one risk factor. It is intimately related to other 'diseases' through shared risk factors and pathophysiology. We also found that people with established renal disease participated enthusiastically in a pharmacological treatment programme, with excellent clinical responses that predict a marked reduction in renal failure and cardiovascular morbidity and mortality over the intermediate term. 3. It is likely that most other causes of excess mortality in Aboriginal people are, like renal disease, multideterminant, with a substantial base of shared risk factors. They are probably equally susceptible to modification. We must move away from 'single-cause' disease models, eliminate counterproductive specialty barriers and rectify the unbalanced focus and resource commitment to hospital-based, high technology treatments of people with advanced and irreversible disease. We must advocate for coherent, sustained, integrated public health and primary care programmes to improve the whole health profile and for screening and treatment programmes to modify the course of disease in people already afflicted.

Albuminuria↗

What "Dr. Mom" ordered: a community-based exploratory study of parental self-care responses to children's ADHD symptoms.

Little is known about family initiated self-care interventions in response to symptoms of attention deficit/hyperactivity disorder (ADHD), and how self-care may co-exist with professional treatments. This paper explores parental self-care strategies for children with hyperactivity or attention problems, and examines factors and domains that influence their use from the mixed method perspective. As part of a longitudinal cohort study of ADHD detection and service use, caregivers of a representative US community sample of 266 children at high risk for ADHD completed a questionnaire that assessed five self-care strategies (behavior modification, coping, diet, over-the-counter medication use and religious practices), and made open-ended inquiry about discipline changes in response to behavioral concerns. Questionnaire responses were analyzed using logistic regression approaches. Open-ended answers were open coded; secondary analysis followed Spradley's model of domain analysis. Quantitative findings showed that behavior modification was the most commonly tried self-care strategy, followed by coping, diet, and religious practices. Over-the-counter trial was least common. The parents of professionally treated children were more likely to have employed behavior modification, coping strategies and over-the-counter medications than the parents of untreated children. Two-thirds of parents had changed their disciplinary action within three domains that were identified through qualitative analysis, including changes related to (a) the prevention of disciplinary problems (e.g., sustain eye contact, activation, consistency, clear instructions), (b) the solution of disciplinary problems (e.g., time-outs; privilege removal), and (c) parental coping associated with disciplinary problems (e.g., control own emotions, become less judgmental and more tolerant, and develop more appropriate expectations). These findings suggest that self-care strategies are commonly employed and appear to co-exist with professional treatment. Therefore, healthcare providers should actively explore parents' use of such strategies as some of them may interfere with prescribed treatments (e.g., over-the-counter) or absorb parental resources without likely benefit (e.g., diet).

Adaptation, Psychological↗

Laboratory validation study of drug evaluation and classification program: alprazolam, d-amphetamine, codeine, and marijuana.

The Drug Evaluation and Classification (DEC) program is used by police agencies to identify drivers impaired because of drug use and to determine the class(es) of drug causing the impairment. The primary goal of this study was to determine the validity of the DEC evaluation in predicting whether research volunteers were administered alprazolam, d-amphetamine, codeine, or marijuana. A secondary goal was to determine the accuracy of Drug Recognition Examiners (DREs) in detecting if subjects were dosed with these drugs. Community volunteers (n = 48) were administered alprazolam (0, 1, 2 mg), d-amphetamine (0, 12.5, 25 mg), codeine (0, 60, 120 mg), or marijuana (0, 3.58% THC) in a double-blind, randomized, between-subject design. A single drug dose or placebo was administered at each experimental session, and blood samples were obtained before and after dosing. With the exception of marijuana, plasma drug concentration was at or near maximum during the DEC evaluation. The ability of the DEC evaluation to predict the intake of alprazolam, d-amphetamine, codeine, or marijuana was optimal when using 2-7 variables from the evaluation. DREs' decisions of impairment were consistent with the administration of any active drug in 76% of cases, and their drug class decisions were consistent with toxicology in 32% of cases, according to standards of the International Association of Chiefs of Police. These findings suggest that the DEC evaluation can be used to predict accurately acute administration of alprazolam, d-amphetamine, codeine, and marijuana and that predictions of drug use may be improved by focusing on a subset of variables.

Adult↗

Adaptations in bacterial catabolic enzyme activity and community structure in membrane-coupled bioreactors fed simple synthetic wastewater.

Membrane-coupled bioreactors (MBRs) offer substantial benefits compared to conventional reactor designs for biological wastewater treatment. MBR treatment efficiency, however, has not been optimized because the effects of the MBR on process microbiology are poorly understood. In this study, the structure and function of the microbial communities growing in MBRs fed simple synthetic wastewater were investigated. In four starch-fed MBRs, the bacterial community substantially increased its alpha-glucosidase affinity (>1000-fold), while the leucine aminopeptidase and heptanoate esterase affinities increased slightly (<40-fold) or remained relatively constant. Concomitant to these physiological adaptations, shifts in the bacterial community structure in two of the starch-fed MBRs were detected by PCR-DGGE. Four of the bacterial populations detected by PCR-DGGE were isolated and exhibited specific growth rates in batch culture ranging from 0.009 to 0.22 h(-1). Our results suggest that bacterial communities growing under increasingly stringent nutrient limitation adapt their enzyme activities primarily for the nutrients provided, but that there is also a more subtle response not linked to the substrates included in the feed medium. Our research also demonstrates that MBRs can support relatively complex bacterial communities even on simple feed media.

Adaptation, Physiological↗

Sampling strategy in molecular microbial ecology: influence of soil sample size on DNA fingerprinting analysis of fungal and bacterial communities.

Assessing soil microbial community structure by the use of molecular techniques requires a satisfactory sampling strategy that takes into account the high microbial diversity and the heterogeneous distribution of microorganisms in the soil matrix. The influence of the sample size of three different soil types (sand, silt and clay soils) on the DNA yield and analysis of bacterial and fungal community structure were investigated. Six sample sizes from 0.125 g to 4 g were evaluated. The genetic community structure was assessed by automated ribosomal intergenic spacer analysis (A-RISA fingerprint). Variations between bacterial (B-ARISA) and fungal (F-ARISA) community structure were quantified by using principal component analysis (PCA). DNA yields were positively correlated with the sample size for the sandy and silty soils, suggesting an influence of the sample size on DNA recovery, whereas no correlation was observed in the clay soil. B-ARISA was shown to be consistent between the different sample sizes for each soil type indicating that the sampling procedure has no influence on the assessment of bacterial community structure. On the contrary for F-ARISA profiles, strong variations were observed between replicates of the smaller samples (<1 g). Principal component analysis analysis revealed that sampling aliquots of soil > or =1 g are required to obtain robust and reproducible fingerprinting analysis of the genetic structure of fungal communities. However, the smallest samples could be adequate for the detection of minor populations masked by dominant ones in larger samples. The sampling strategy should therefore be different according to the objectives: rather large soil samples (> or =1 g) for a global description of the genetic community structure, or a large number of small soil samples for a more complete inventory of microbial diversity.

Bacteria↗

[Is troponin I useful for predicting in-hospital risk for unstable angina patients in a community hospital? Results of a prospective study].

INTRODUCTION AND OBJECTIVES: Before including troponin I detection in the daily practice of our hospital we performed a prospective study to determine its real usefulness and to establish the best cut-off point. METHODS: We studied 82 consecutive patients admitted with unstable angina to a community hospital. Troponin I was determined (> 10 h after chest pain). Patients were referred to a tertiary hospital for catheterization/revascularization if clinical events developed. RESULTS: Twenty-five patients (31%) suffered events during admission: recurrent angina in 23 cases (28%); heart failure in 5 (6%); exitus in 3 (4%); myocardial infarction in 1 (1%). The cut-off point for troponin I that best predicted events was 0.1 ng/ml. Patients with troponin I > 0.1 (34 patients, 42%) experienced more events [47 vs. 19%; OR = 3.8 (1.4-10.4); p = 0.01] and had higher rates of recurrent angina (42 vs. 19%), heart failure (12 vs. 2%) and exitus (9 vs 0%). Patients with ECG changes and troponin I > 0.1 showed a significantly higher percentage of events (63%) than those with ECG changes alone (23%) or troponin I > 0.1 alone (15%) or those without ECG changes and troponin I < 0.1 (17%) (p < 0.0001). CONCLUSIONS: Troponin I elevation is useful for predicting in-hospital risk for unstable angina patients admitted to a community hospital. A low cut-off value (0.1 ng/ml) predicts events. The association of ECG changes and high troponin I identifies a population at very high risk; however, the absence of both variables in patients with a diagnosis of unstable angina does not preclude the development of events.

Aged↗

Abundance of Tn3, Tn21, and Tn501 transposase (tnpA) sequences in bacterial community DNA from marine environments.

The occurrence of the tnpA genes of the transposons Tn3, Tn21, and Tn501 was assessed in total bacterial community DNA isolated from different marine environments. The PCR technique was employed, together with most probable number statistics, to determine the abundance of the target tnpA genes. All three genes could be detected, and the Tn21 tnpA sequences predominated in all samples. The smallest amount of total community DNA in which the Tn21 tnpA sequence could be detected was 0.037 ng, and on the basis of our results, we estimated that this sequence was present in 1 of 1,000 to 10,000 bacteria. Hybridization of the PCR products with the respective tnpA probes verified the Tn21 and Tn501 tnpA sequences but only some of the Tn3 tnpA amplification products. The distribution and dissemination of transposons in natural bacterial communities are discussed.

Bacteria↗

Breastfeeding and the risk of life-threatening enterotoxigenic Escherichia coli diarrhea in Bangladeshi infants and children.

OBJECTIVE: To assess the relationship between breastfeeding and the risk of life-threatening enterotoxigenic Escherichia coli (ETEC) diarrhea among Bangladeshi infants and young children <36 months of age. DESIGN: Case-control study. SETTING: A rural Bangladesh community. PARTICIPANTS: A total of 168 cases with clinically severe ETEC diarrhea detected in a treatment center-based surveillance system during 1985 to 1986 and 3679 controls selected in three surveys of the same community during the same calendar interval. OUTCOMES: Cases and controls were compared for the frequency of antecedent breastfeeding patterns. RESULTS: Compared with other feeding modes, exclusive breastfeeding of infants was associated with significant protection against severe ETEC diarrhea (relative risk [RR] = 0.51; 95% confidence interval [CI]: 0.28,0.96). However, during the second and third years of life, the risk of this outcome was similar in both breastfed and nonbreastfed children (RR = 0.98; 95% CI: 0.45,2.12), and no significant overall protective association between breastfeeding and severe ETEC diarrhea was evident during the first 3 years of life (RR = 0.86; 95% CI: 0.43,1. 74). CONCLUSIONS: Exclusive breastfeeding appeared to protect infants against severe ETEC diarrhea, but breastfeeding was not associated with protection after infancy, nor was it associated with a major overall reduction of severe ETEC disease during the first 3 years of life. Although not diminishing the importance of breastfeeding, our findings suggest that other interventions, such as immunization and education about proper food hygiene, may also be required in efforts to prevent this major pediatric disease.

Bangladesh↗

Community spread of Legionella pneumophila serogroup 1 in temporal relation to a nosocomial outbreak.

To clarify whether a nosocomial outbreak of legionnaires' disease in the Värnamo hospital in Sweden was part of a wider outbreak in the Värnamo community a number of investigations were performed. First, the proportion of cases of legionnaires' disease in a group with nosocomially acquired pneumonia (11%) was compared to the proportion within a group with community-acquired pneumonia (14%) and the difference was found not to be significant (p > 0.05). Second, the proportion of the nursing staff at the Värnamo hospital with an elevated antibody titre (> or = 16) to Legionella pneumophila serogroup (sg) 1 (33%, 84/258) was compared to the proportion in a group of local residents of Värnamo community (26%, 25/96) and found not to be significant; in contrast, comparison with the proportion in a group from the assistant nursing staff at another hospital 60 km away (5%, 4/80) was highly significant (p < 0.001). Furthermore, Legionella species were cultured from samples drawn from the hospital water supply as well from the water supply from municipal buildings. In 1996 a follow-up study was conducted, which showed that < 1% of the assistant nurses and local residents had an elevated titre to L. pneumophila sg 1. These results indicate that there was a temporary spread of L. pneumophila sg 1 in the Värnamo community at the beginning of 1991, both in the local hospital and the surrounding community. This implies that physicians should be aware of community-acquired cases of legionnaires' disease when a nosocomial outbreak is detected.

Adult↗

Presenting problems in black children referred for outpatient psychological consultation in South Africa.

An examination of outpatient referrals for psychological consultation at a psychiatric hospital in South Africa was undertaken. Over an 18-month period, 87.1% of a total of 31 children were referred with problems of poor school performance. Behaviour problems were underrepresented. The results are discussed in the context of inadequate community mental health services, which are implicated in the under-detection of childhood psychopathology.

Black or African American↗

The effects of dredge-spoil dumping on a shallow water soft-sediment community in the Solitary Islands Marine Park, NSW, Australia.

In December 1999, 28,000 m3 of sediment was dredged from two sites within the harbour at Coffs Harbour, NSW. Dredging was carried out using a trailing suction hopper-dredge which transported the spoil to a shallow (6 m) site within the adjacent Solitary Islands Marine Park for disposal. Evaluation of the effects of the dredge-spoil dumping at the receiving site was conducted by taking replicated van Veen grab samples at the disposal site and at two control sites, before, immediately after, and three months after dumping. The results indicated that dredge-spoil dumping had no detectable effect on either the structure of the invertebrate community or the physical characteristics of sediment at the receiving site. Although there were some significant faunistic differences between samples from the disposal site and the control sites immediately following dumping, these were related to pre-existing differences between sites rather than to the effects of dredge-spoil disposal. Four principal factors are likely to have contributed to the lack of impact: (i) dredged material had similar sedimentary characteristics to those at the receiving site; (ii) dredged material was free from contaminants; (iii) the disposal method systematically distributed a number of shallow layers of sediment over the disposal site and thus motile macrofauna had the opportunity to migrate upwards between passes of the barge; and (iv) the disposal site was in a high energy environment where the resident biota are likely to be adapted to dynamic sedimentary conditions. The lack of detectable effects suggests that the disposal strategy was one which minimized impacts within an area which has high conservation value and should thus be adopted as a model for future works within the region.

Adaptation, Physiological↗