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A A Zaidi

Publications and source records attributed to A A Zaidi.

At least 19 recordsLinked to original sources
PubMed2006

Coat protein gene diversity among Chrysanthemum virus B isolates from India.

The complete coat protein (CP) sequences from 29 Indian isolates of Chrysanthemum virus B (CVB) were determined and analysed in relation to other previously characterized carlaviruses. The CP genes of the Indian CVB isolates were highly heterogeneous, sharing nucleotide sequence identities of 74-98%. Based on phylogenetic analyses, the isolates formed three groups potentially representing either two or three major CVB strain groupings. Recombination analysis revealed at least one definite recombination event involving the exchange of sequences between members of different groups. To our knowledge this is the first reported evidence of homologous recombination in carlaviruses.

Amino Acid Sequence↗
PubMed2006

Coat protein sequence shows that Cucumber mosaic virus isolate from geraniums (Pelargonium spp.) belongs to subgroup II.

A viral disease was identified on geraniums (Pelargonium spp.) grown in a greenhouse at the Institute of Himalayan Bioresource Technology (IHBT), Palampur, exhibiting mild mottling and stunting. The causal virus (Cucumber mosaic virus, CMV) was identified and characterized on the basis of host range, aphid transmission, enzyme linked immunosorbent assay (ELISA), DNA-RNA hybridization and reverse transcription polymerase chain reaction (RT-PCR). A complete coat protein (CP) gene was amplified using degenerate primers and sequenced. The CP gene showed nucleotide and amino acid homology up to 97%-98% and 96%-99%, respectively with the sequences of CMV subgroup II. The CP gene also showed homologies of 75%-97% in nucleotide and 77%-96% in amino acid with the CMV Indian isolates infecting various crops. On the basis of sequence homology, it was concluded that CMV-infecting geraniums in India belong to subgroup II.

Amino Acid Sequence↗
PubMed2006

Plant parasitic and vector nematodes associated with Asiatic and Oriental hybrid lilies.

A survey for distribution and abundance of plant parasitic nematodes in fields grown to Lilium in Himachal Pradesh, India at four study sites viz. Nagrota (at 810 m a.s.l.), Palampur (at 1270 m a.s.l.), Sunder Nagar (at 1400 m a.s.l.) and Chail (at 2250 m a.s.l.) was carried out. Moderate (101-500/200 ml soil) to high (501-1000/200 ml soil) populations of phytonematodes including the vectors for plant viruses (Aphelenchoides avenae, Criconemoides spp., Hoplolaimus spp., Longidorus spp., Paratylenchus spp., Pratylenchus spp., Rhabditis spp., Trichodorus spp., Tylenchoryhnchus spp., Tylenchulus spp. and Xiphinema diversicaudatum) were recorded. Mean population of nematodes was positively correlated with pH in all the study sites, negatively correlated with electrical conductivity (EC), percent organic matter (OM%), available potassium (K) and positively correlated with percent carbon (C%), available nitrogen (N) and available phosphorus (P) in all but one study site. The highest incidence of virus-vector nematodes viz. X. diversicaudatum, Longidorus spp. and Trichodorus spp. was recorded at Palampur. Only Strawberry latent ringspot nepovirus (SLRSV) was detected in Lilium cvs. Star Gazer Max and Galeili by Enzyme Linked Immunosorbent Assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR) and in X. diversicaudatum associated with the cultivars by RT-PCR. Cucumis sativus used as bait plants showed SLRSV symptoms after 15 days of nematode inoculation and further SLRSV was again detected by ELISA and RT-PCR in C. sativus plants confirming the transmission of SLRSV by X. diversicaudatum in Lilium.

Animals↗
PubMed2006

Pneumatic retinopexy: success rate and complications.

AIM: To evaluate the success rate and complications of pneumatic retinopexy performed at a university hospital and to identify which patients are best suited for pneumatic retinopexy. METHODS: This was an interventional case series. Retrospective review of 61 patients who had pneumatic retinopexy performed by two retina surgeons at two University of California, San Francisco hospitals between 1998 and 2004. Patients who had been treated for rhegmatogenous retinal detachment (RRD) with pneumatic retinopexy were identified by reviewing operative reports and billing records. The primary outcome measure was anatomical reattachment of the retina with a single intervention. Secondary outcome measures included postoperative visual acuity and postoperative complications. RESULTS: 33 of 61 (54%) cases were successful with a single procedure. 40 of 61 (66%) cases were successful with repeat injection of gas or laser retinopexy alone. All cases had anatomical success at final follow up. Age, myopia, lens status, and number of breaks were not proved to be risk factors for failure. The average duration of follow up was 15 months. CONCLUSIONS: In this case series, pneumatic retinopexy was less effective for the repair of RRD than most large published reports. However, failure of pneumatic retinopexy followed by scleral buckle or pars plana vitrectomy did not negatively influence visual acuity at final follow up.

Adult↗
PubMed2003

Molecular characterization of a carnation etched ring virus isolate from India.

Incidence of the Carnation etched ring virus (CERV), the only DNA virus reported to date on carnation, was investigated by a bioassay using a partially purified virus as inoculum and then by a double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). Out of 61 carnation cultivars analyzed 41 (67%) were found positive. The virus positivity was verified by polymerase chain reaction (PCR) and nucleotide sequencing. The amplified 1349 bp fragment was by about 98% and 96% identical with respect to coat protein (CP) and enzymatic polyprotein genes, respectively, as compared to the sequences available in the database. In terms of amino acid sequence similarity, the homology values were 99% and 97%, respectively. Comparison with other caulimoviruses revealed that CERV is most closely related to the Cauliflower mosaic virus (CaMV). High genetic stability of CERV may be attributed to the fact that it has evolved from the same initial sequence in an original host. Because of global market of cut flowers and vegetative propagation it has been dispersed around the world.

Amino Acid Sequence↗
PubMed2001

Predictability of medical students' performance at the Aga Khan University from admission test scores, interview ratings and systems of education.

INTRODUCTION: Performance in an admission test and carefully conducted, structured interview provides a uniform basis for the assessment of applicants prepared in different systems of education for admission to an institute of higher professional learning. We studied the predictability of the system of education followed by the students prior to entrance into the Medical College, the admission test scores, and interview ratings on performance after five trimesters at the Aga Khan University Medical College. METHOD: A cohort of 374 medical students who were admitted during 1989--1994, were considered. The associations between the admission test score, interview ratings, system of education, and the scores obtained for anatomy, physiology, biochemistry and community health sciences examinations held after five trimesters were analysed using appropriate statistical procedures. RESULTS: Interview ratings were associated with the scores in Physiology but not other subjects. The chief finding of this study was the association between the system of education and performance in both the admission test and the examination after five trimesters. Students who followed the British school curricula for 13 years scored significantly higher than those who followed the 12 years of the Pakistani system. When controlled for the admission test score, the difference in mean scores of the two groups was still evident for two subjects; community health sciences and physiology. CONCLUSION: We believe that the evidence indicates differences in learning methods inculcated by the system of education prior to entry into the Medical College, notwithstanding the 1-year difference in duration of education.

Analysis of Variance↗
PubMed1999

Estimated incidence and prevalence of genital Chlamydia trachomatis infections in the United States, 1996.

BACKGROUND AND OBJECTIVE: Because genital Chlamydia trachomatis infections and their sequelae have a major impact on individuals and the health care system, it is important to periodically update estimates of chlamydia incidence and prevalence in the United States. STUDY DESIGN: Chlamydia incidence and prevalence were estimated using: (1) a method based on estimates of population-specific chlamydia prevalence, and (2) a method based on the chlamydia-to-gonorrhea case rate ratio. RESULTS: Using the prevalence-based method, point prevalence among persons 15 to 44 years of age was estimated to be 1.6 million chlamydial infections, and annual incidence, 2.4 million cases per year. Using a method based on the ratio of reported gonorrhea to chlamydia, incidence was estimated to be 2.8 million infections per year, and prevalence, 1.9 million. Adjustment for sensitivity of diagnostic tests yielded annual incidence estimates of 2.5 to 3.3 million infections. CONCLUSIONS: Using two methods, we estimated the annual incidence of chlamydial infections in the United States among persons 15 to 44 years of age to be approximately 3 million infections. Critical data needed for more precise estimates include: sensitivity of current diagnostics, better data on infections in males, the current extent of underdetection and underreporting, and better data on duration of infection in men and women.

Adolescent↗
PubMed1999

Syphilis, gonorrhoea, and drug abuse among pregnant women in Jefferson County, Alabama, US, 1980-94: monitoring trends through systematically collected health services data.

OBJECTIVE: To assess the association between self reported drug abuse and syphilis and gonorrhoea among pregnant women, Jefferson County, Alabama, United States, 1980-94. STUDY DESIGN: We analysed a prenatal care database and assessed the association of self reported drug use with seropositive syphilis and gonorrhoea using prevalence rates, multiple logistic regression models, and the Pearson correlation coefficient (r) for trends. RESULTS: Overall, 5.5% of the women acknowledged drug abuse, 1.4% had seropositive syphilis, and 4.8% had gonorrhoea. In a multivariate analysis, drug abuse was associated with syphilis (odds ratio 2.9, 95% confidence interval 1.6, 5.3) but not with gonorrhoea. Trends in the annual prevalence of drug abuse closely paralleled trends in the annual prevalence of syphilis, including simultaneous peaks in 1992 (drug abuse, 9.1%; syphilis, 3.2%). There was no such parallel trend between drug abuse and gonorrhoea. Annual prevalence of drug abuse correlated with the prevalence of syphilis (r = 0.89, p = 0.001) more than with the prevalence of gonorrhoea (r = 0.45, p = 0.201). CONCLUSION: Among pregnant women, an increase in drug abuse was closely associated with an epidemic of syphilis, but not of gonorrhoea. Systematically collected prenatal care data can usefully supplement surveillance of diseases and behavioural risk factors associated with them.

Adult↗
PubMed1998

Decline in sexually transmitted disease prevalence in female Bolivian sex workers: impact of an HIV prevention project.

OBJECTIVE: To implement an HIV prevention intervention among female commercial sex workers (CSW), and to monitor key outcomes using routinely collected clinical and laboratory data. DESIGN: Cross-sectional and longitudinal analysis of data from an open-enrollment cohort. SETTING: One public sexually transmitted disease (STD) clinic and about 25 brothels in La Paz, Bolivia. PARTICIPANTS: A total of 508 female CSW who work at brothels and attend a public STD clinic. INTERVENTION: Improved STD clinical care, supported by periodic laboratory testing, and behavioral interventions performed by a local non-governmental organization. MAIN OUTCOME MEASURES: Prevalence of gonorrhea, syphilis (reactive plasma reagin titer > or = 1 : 16), genital ulcer disease, chlamydial infection, and trichomoniasis; self-reported condom use in the previous month; and HIV seroprevalence. RESULTS: From 1992 through 1995, prevalence of gonorrhea among CSW declined from 25.8 to 9.9% (P < 0.001), syphilis from 14.9 to 8.7% (P = 0.02), and genital ulcer disease from 5.7 to 1.3% (P = 0.006); trends in prevalence of chlamydial infection and trichomoniasis were not significant. Self-reported condom use during vaginal sex in the past month increased from 36.3 to 72.5% (P < 0.001). In a multivariate analysis, condom use was inversely associated with gonorrhea [odds ratio (OR), 0.63; 95% confidence interval (Cl), 0.41-0.97], syphilis (OR, 0.39; 95% Cl, 0.23-0.64), and trichomoniasis (OR, 0.44; 95% Cl, 0.32-0.71). In 1995, HIV seroprevalence among CSW was 0.1%. CONCLUSION: Effective prevention interventions for female CSW can be implemented through public services and non-governmental organizations while HIV rates are still low, and key outcomes can be monitored using data obtained from periodic screening examinations.

Adult↗
PubMed1998

Increase in endocervical CD4 lymphocytes among women with nonulcerative sexually transmitted diseases.

To assess associations of nonulcerative sexually transmitted diseases (STDs) with human immunodeficiency virus (HIV)-susceptible leukocytes on female genital mucosa, cervicovaginal specimens from 32 HIV-negative STD clinic patients with gonorrhea, chlamydial infection, or trichomoniasis were compared with specimens from 32 clinic patients without these infections. Twenty-eight patients had single infections (15 gonorrhea, 10 chlamydial infection, 3 trichomoniasis), and 4 had dual infections. A saline vaginal wash and saline suspensions of vaginal wall scrapings, ectocervical scrapings, and endocervical brushings were analyzed by flow cytometry. Specimens from the endocervix had the highest proportions of lymphocytes, monocytes, and Langerhans' cells. The median number of endocervical CD4 lymphocytes/10,000 cells was greater among patients with STDs than among those without (476 vs. 245; P < .001). These data suggest that the endocervix may have a particularly important role in heterosexual HIV transmission and that nonulcerative STDs may facilitate HIV transmission by increasing the presence of CD4 lymphocytes at this site.

Adolescent↗
PubMed1998

Human immunodeficiency virus partner notification. Cost and effectiveness data from an attempted randomized controlled trial.

OBJECTIVE: Determine the cost and effectiveness of partner notification for human immunodeficiency virus (HIV) infection. METHODS: Persons testing HIV positive in three areas were randomly assigned one of four approaches to partner notification. Analysis plans changed because disease intervention specialists notified many partners from the patient referral group. We dropped the patient referral group and combined the others to assess the cost and effectiveness of provider referral. RESULTS: The 1,070 patients reported 8,633 partners. Of those 1,035 were located via record search or in person. A previous positive test was reported by 248 partners. Of the 787 others, 560 were tested: 438 were HIV negative and 122 were newly identified as HIV positive. The intervention specialist's time totaled 197 minutes per index patient. The cost of the intervention specialist's time, travel, and overhead was $268,425: $251 per index patient, $427 per partner notified, or $2,200 per new HIV infection identified. No demographic characteristic of the index patient strongly predicted the likelihood of finding an infected partner. CONCLUSION: We could not compare the effectiveness of different partner notification approaches because of frequent crossover between randomized groups. The cost of partner notification can be compared with other approaches to acquired immunodeficiency syndrome prevention, but the benefits are not easily measured. We do not know the number of HIV cases prevented or the value of fulfilling the ethical obligation to warn partners of a potential threat to their health.

Adolescent↗
PubMed1998

Gonorrhea in the United States, 1981-1996. Demographic and geographic trends.

OBJECTIVE: To describe demographic and geographic trends in gonorrhea incidence in the United States from 1981 through 1996. STUDY DESIGN: We analyzed aggregate gonorrhea cases reported to the Centers for Disease Control and Prevention by the 50 states, District of Columbia, and 63 large cities. Annual incidence rates (cases/100,000 persons) were calculated. RESULTS: Between 1981 and 1996, the incidence of reported gonorrhea decreased 71.3%, from 431.5 to 124.0 cases/100,000. However, rates among blacks were 35 times higher than rates among whites in 1996 (684.6 versus 19.4) compared with 11 times higher in 1981 (1,894.3 versus 164.3). Among women of all races, 15 to 19 year olds had the highest rates (716.6 in 1996), whereas among men, 20 to 24 year olds had the highest rates (512.9 in 1996). Southern states had higher rates than other regions. CONCLUSIONS: Large segments of the population, including adolescents, young adults, and blacks, continue to have high rates of gonococcal infection; prevention programs and health care providers should address the needs of these groups.

Adolescent↗
PubMed1998

Group counseling to prevent sexually transmitted disease and HIV: a randomized controlled trial.

OBJECTIVE: To compare prevention effectiveness of multisession group counseling with standard HIV prevention counseling for reducing risk behaviors and new sexually transmitted diseases (STDs). METHODS: Small groups of consenting STD clinic patients were randomized to four 1-hour small group counseling interventions based on the information-motivation-behavioral skills (IMB) model with a booster session at 2 months or to the standard two 20-minute individual counseling sessions. Follow-up interviews and examinations were 2, 6, 9, and 12 months after enrollment. RESULTS: From March 1992 through June 1993, 996 (59%) of 1,681 eligible persons were enrolled; 32 (3%) tested HIV-positive and were excluded. Intervention attendance was 98% for one session, and 47% attended four or five counseling sessions. Follow-up was similar for both groups: 72% attended at least once; 47% returned at 12 months. Both groups had similar increases in condom use and decreases in number of partners, and similar number of new infections with gonorrhea (14%), chlamydia (10%), or syphilis (2%). CONCLUSIONS: Two 20-minute counseling sessions were as effective as four 1-hour group sessions for reducing risk behavior and STD incidence in an STD clinic patient population.

Adolescent↗
PubMed1997

Geography of AIDS-associated Kaposi's sarcoma in Europe.

BACKGROUND: Classical Kaposi's sarcoma (KS) is about four times more common in southern Europeans than in northern Europeans. OBJECTIVE: To describe the epidemiology of AIDS-associated KS (AIDS-KS) in Europe and to determine whether it occurs with increased frequency in southern Europe. METHODS: Analysis of the 'European non-aggregate AIDS data set', as of September 1995. Countries with a cumulative total of > or = 50 KS cases as the presenting manifestation of AIDS were included. Homosexual men were excluded from south versus non-south comparisons because of possible confounding effects due to their route of HIV transmission. RESULTS: KS was the presenting manifestation of AIDS for 13.3% (16,367 out of 122,679) of men and 2% (491 out of 24,826) of women. In all countries, the risk for KS was higher in individuals who acquired HIV infection via sexual rather than parenteral transmission. Among AIDS patients, there is little difference by sex in the risk of KS in injecting drug users (IDU) or transfusion recipients. The percentage with KS increased with age among homosexual and bisexual men, from 10% in the age group 15-19 years to 23% in the age group 30-39 years. In all countries, the percentage with KS declined over time. The risk of KS was not significantly higher in southern Europe. The percentage with KS in southern Europe was slightly lower than in northern Europe (P > 0.1) in male IDU (1.8% versus 2.1%), and only slightly higher (P > 0.1) in female IDU (1.5% versus 1.1%), in male transfusion recipients (3.5% versus 3.0%), in female transfusion recipients (2.4% versus 2.3%), and in both heterosexual men (7.5% versus 6.2%) and women (2.0% versus 1.6%) excluding those originating from countries where heterosexual HIV transmission is frequent. CONCLUSIONS: The strong geographic predilection described for classical KS in southern Europe was not seen for AIDS-KS. If KS is caused by a viral infection in an immunodeficient host, our findings suggest the geographical variations in classical KS are not due to variation in prevalence of the causative virus but may be due to geographical variations in the prevalence of a form of mild immunodeficiency.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Partner notification for syphilis: a randomized, controlled trial of three approaches.

OBJECTIVE: To determine the cost and effectiveness of three approaches to partner notification for infectious syphilis. STUDY DESIGN: People with syphilis were randomly assigned to: (1) notification of partners by patients themselves within 2 days or disease intervention specialists would notify them; (2) immediate notification by intervention specialist; or (3) immediate notification by intervention specialists, who had the option of drawing blood in the field. Costs of intervention specialists' time, travel, and overhead were measured. Intention-to-treat analysis measured outcomes per randomized index patient. RESULTS: From December, 1990 through March, 1993, 1,966 index patients with syphilis (primary 9%; secondary 18%; and early latent 73%) were randomized in Broward County (Ft. Lauderdale), Florida (1,191); Tampa, Florida (569); and Paterson, New Jersey (206). Index patients reported 11,272 potentially exposed partners and sufficient information to initiate investigations for 2,761. Of these, 2,236 were located, 367 had newly identified infections, and 870 others received preventive treatment. The three partner notification approaches had similar success locating partners (1.1-1.2 per index patient) and treating partners (0.61-0.67 per index). The cost was $317 to $362 per partner treated; the optimal strategy differed by study site. CONCLUSIONS: Partner notification identified many infected and potentially infected people. The cost and effectiveness of the three types of provider notification were similar. Alternative approaches are needed to reach infected partners who could not be notified.

Adult↗
PubMed1997

Sociodemographic factors and the variation in syphilis rates among US counties, 1984 through 1993: an ecological analysis.

OBJECTIVES: Syphilis in the United States is focally distributed, with high incidence rates in the South and in metropolitan areas nationwide. In this study an ecological analysis, using the county as the unit of analysis, was performed to generate hypotheses about community-level determinants of syphilis rates. METHODS: Bivariate rank correlations and multivariate, backward stepwise elimination linear regressions were performed. Mean annual incidence of primary- and secondary-stage syphilis in a county was the dependent variable, and county sociodemographic characteristics (from census data) were the independent variables. RESULTS: In the multivariate regression model, sociodemographic characteristics accounted for 71% of the variation in syphilis rates among counties. With other factors accounted for, the most highly correlated characteristics were percentage non-Hispanic Black population, county location in the South, percentage of the population that was urban, percentage Hispanic population, and percentage of births to women younger than 20 years. CONCLUSIONS: Most of the variation in syphilis rates among counties is accounted for by sociodemographic characteristics. Identification and remediation of modifiable health determinants for which these factors are markers are needed to improve the health status of these populations.

Adolescent↗