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Biomedical subjects

S Aral

Publications and source records attributed to S Aral.

11 recordsLinked to original sources

Emerging and reemerging infectious diseases: a multidisciplinary perspective.

Predictions that infectious diseases would be eliminated as a major threat to human health have been shattered by emerging and reemerging infections, among them acquired immunodeficiency syndrome (AIDS), hemorrhagic fevers, marked increases in infections caused by antimicrobial-resistant bacteria, and the resurgence of tuberculosis and malaria. Understanding the dynamics of emerging and reemerging infections is critical to efforts to reduce the morbidity and mortality of such infections, to establish policy related to preparedness for infectious threats, and for decisions on where to use limited resources in the fight against infections. In order to offer a multidisciplinary perspective, 23 infectious disease specialists, epidemiologists, geneticists, microbiologists, and population biologists participated in an open forum at Emory University on emerging and reemerging infectious diseases. As summarized below, the group addressed questions about the definition, the identification, the factors responsible for, and multidisciplinary approaches to emerging and reemerging infections.

Acquired Immunodeficiency Syndrome↗

Quantitative non-radioactive clonality analysis of human leukemic cells and progenitors using the human androgen receptor (AR) gene.

Clonal analysis of FACS-purified primitive hematopoietic stem cells and of their progeny as assessed by the progenitors obtained from long-term cultures requires PCR-based approaches, mainly because of the low number of cells available. We have developed a non-radioactive androgen receptor (AR) assay which allows a simple and quantitative evaluation of the clonality of hematopoietic cells and progenitors. In this approach 5' AR primer is labelled by fluorescein and the amplified product is run on a sequencing gel which allows evaluation of the intensity of the fluorescent peaks generated. A computer software then analyzes the reduction of the intensity of the peaks on HpaII-digested samples. In order to determine the feasibility of the technique, we analyzed the clonality of leukemic cells from a patient with an acute-phase CMML which showed a typical clonal pattern of her leukemic DNA sample (WBC = 300 x 10(9)/I) using phosphoglycerate kinase (PGK) analysis. The same sample was then analyzed with either radioactive- or fluorescein-labelled AR primers, showing a typical clonal pattern (complete disappearance of one allele after HpaII digestion). A short-term clonogenic assay was then set up on methylcellulose and clonogenic progenitors were individually analyzed. All 24 colonies tested showed a typical clonal pattern with the disappearance of the same allele on each sample after HpaII digestion, indicating that they all derived from the same leukemic stem cell. Using this approach we then analyzed 94 patients with several hematologic malignancies and quantification of their fluorescent peaks. Fifty-four percent of the patients were clearly heterozygous (ie, a difference of > or = 2 CAG repeats was present between the two copies of the gene) and could be analyzed in an automatic sequencer using the fluorescent primers. Bone marrow mononuclear cells from all patients with acute myeloid leukemia (AML) showed a clonal or oligoclonal pattern at diagnosis whereas a polyclonal pattern was seen when remission was obtained. Similarly, out of 21 patients with a diagnosis of myelodysplastic syndrome (MDS), a clonal pattern was demonstrated in 10 whereas an oligoclonal or non-clonal pattern was shown in 11. These results show that this non-radioactive and safe technology can now be used on a large scale to evaluate the clonality of highly purified hematopoietic stem cells and their progenitors in hematopoietic malignancies and this might allow new insights into the targets of clonal amplification.

Acute Disease↗

Primary infertility: characteristics of women in North America according to pathological findings.

STUDY OBJECTIVE: To determine, in women with primary infertility, whether specific characteristics or behavioural factors are associated with the various pathological conditions identified as contributing to the infertility. DESIGN: Case-control study. SETTING: Seven institutions in the USA or Canada. PARTICIPANTS: Study subjects were 1750 women who presented with primary infertility, among whom the main pathological cause of infertility was male factor (417), tubal obstruction (231), endometriosis (194), luteal phase defects (153), other ovulatory problems (193), cervical abnormalities (92), and polycystic ovarian disease (84) and 1765 control women who delivered their first child at the same institution. MAIN RESULTS: Except for tubal obstruction and polycystic ovarian disease, the characteristics and behaviours of the women with infertility did not differ appreciably according to the pathological conditions recorded. Women with tubal obstruction had had more sexual partners, an earlier age at first intercourse, were more likely to have used an intrauterine device but less likely to have used a condom, and were more likely to have smoked cigarettes and to have used various recreational drugs than the other women. Women with polycystic ovarian disease were more obese, had had fewer sexual partners, and were less likely to have used cigarettes, contraceptives, and recreational drugs than the other women. CONCLUSIONS: Sexually transmitted infections seem to increase the risk of tubal obstruction but not other causes of infertility. Obesity is associated with polycystic ovarian disease. These data offer few clues to the aetiology of infertility attributed to endometriosis, cervical abnormalities, luteal phase defects, other ovulatory defects, or to male factors.

Age Factors↗

HIV antibody testing and posttest counseling in the United States: data from the 1989 National Health Interview Survey.

To see how successful human immunodeficiency virus (HIV) counseling and testing efforts have been in testing the United States population, particularly among those at increased risk for HIV infection, we analyzed data from the 1989 National Health Interview Survey. Twenty percent of the NHIS sample (or, in terms of the general US population, an estimated 36 million persons) reported having been tested for HIV antibodies, mostly through blood donations. Although persons with increased risk of HIV infection had been tested and counseled at a much higher rate than the general population, the majority of this group had not yet been tested.

AIDS Serodiagnosis↗

Reliability of sexual histories in heterosexual couples.

BACKGROUND AND OBJECTIVES: Reliability of responses between partners was used as a surrogate to examine the validity of self-reported sexual histories in two samples with different risk and demographic profiles and different intensities of contact with study staff. STUDY DESIGN: Retrospective self-report data were compared between partners and between samples. RESULTS: Despite differences between the two groups, reliability of the sexual history data was comparable. CONCLUSIONS: Further study is needed to examine other methodologies for collecting sensitive data. Intensive contact and rapport building may not be necessary.

Adult↗

Age at first coitus. A marker for risky sexual behavior in women.

This study examines whether riskier sexual behavior or duration of sexual experience explains why women who become sexually active earlier in life have a higher prevalence of sexually transmitted disease (STD). Responses to a self-administered questionnaire on risk behavior from 4,342 single women attending Planned Parenthood clinics in Pennsylvania were analyzed. Logistic regression was used to control for years of sexual activity, race, and amount of education. Women who became sexually active between the ages of 10 and 14 years were almost 4 times more likely to report having 5 or more sexual partners in the past year (OR = 3.8; 95% CI = 2.6-5.6); 3 times more likely to report having sex with bisexual, intravenous drug-using, or human immunodeficiency virus (HIV)-infected men (OR = 3.5; 95% CI = 2.4-5.0); and twice as likely to report a history of STD within the last 5 years (OR = 2.3; 95% CI = 1.8-3.0) compared with women who became sexually active when they were 17 years of age or older. The analysis suggests that age at first intercourse is a useful marker for risky sexual behavior and history of STD.

Adolescent↗

HIV seroprevalence surveys in sexually transmitted disease clinics.

The Centers for Disease Control, in cooperation with State and local health departments, is conducting human immunodeficiency virus, type 1 (HIV), seroprevalence surveys, using standard protocols, in sexually transmitted disease (STD) clinics in selected metropolitan areas throughout the United States. The surveys are blinded (serologic test results not identified with a person) as well as nonblinded (clients voluntarily agreeing to participate). STD clinics are important sentinel sites for the surveillance of HIV infection because they serve persons who are at increased risk as a result of certain behaviors, such as unprotected sex, homosexual exposure, or intravenous drug use. HIV seroprevalence rates will be obtained in the sentinel clinics each year so that trends in infection can be assessed over an extended period of time. Behaviors that place clients at risk for infection, or protect against infection, are being evaluated in voluntary, nonblinded surveys to define groups for appropriate interventions and to detect changes in response to education and prevention programs. Although inferences drawn from the surveys are limited by the scope of the clinics and clients surveyed, HIV trends in STD clinic client populations should provide a sensitive monitor of the course of the acquired immunodeficiency syndrome (AIDS) epidemic among persons engaging in high-risk sexual behaviors.

Adolescent↗