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Biomedical subjects

H Lee

Publications and source records attributed to H Lee.

At least 703 records · Page 39Linked to original sources
PubMed1991

Randomized, double-blind trial of Lithostat (acetohydroxamic acid) in the palliative treatment of infection-induced urinary calculi.

In a prospective, double-blind, placebo-controlled study, the efficacy and safety of acetohydroxamic acid (AHA) in preventing urinary calculogenesis was evaluated in 94 patients with chronic urinary infection. Stone growth occurred in 17% of the AHA group and in 46% of the placebo group (p less than 0.005). Completely reversible side effects consisting predominantly of psychoneurologic and musculo-integumentary symptoms were more prevalent in the AHA group (p less than 0.01). Side effects which were judged 'intolerable' were experienced by 10 (22.2%) of patients in the AHA group and 2 (4.1%) in the placebo group. It is concluded that AHA treatment is effective, relatively safe, and clinically useful in preventing infection-induced urinary calculogenesis.

Adult↗
PubMed1991

Academic underachievement in children with epilepsy.

Academic achievement was studied in 78 children with epilepsy, ages 5 to 13 years, to determine how seizures, treatment of seizures, and sociocultural factors influence academic achievement. Cognitive abilities were assessed with either the McCarthy Scales of Children's Abilities or the Wechsler Intelligence Scale for Children--Revised. Achievement was measured with the Peabody Individual Achievement Tests. Achievement scores were corrected for cognitive ability (IQ), and underachievement was defined as achievement score 1/2 standard deviation or more below IQ. Information regarding seizure history (severity, duration) and treatment with anticonvulsant drugs was obtained. In addition, the family was extensively interviewed regarding the child's environment, behavior, and demographic background. The Home Observation for Measurement of the Environment (HOME) scale was completed on a home visit. Underachievement was frequent, ranging from 16% (Reading Recognition) to 50% (General Knowledge), but there was no relationship between severity or duration of seizure disorder or total exposure to anticonvulsant medications and achievement. Major determinants of achievement included subscales of the HOME scale, age (older children more likely to be underachieving), and parental education. An equal proportion of newly diagnosed and/or untreated subjects were underachieving compared to those with longstanding epilepsy and anticonvulsant drug treatment.

Adolescent↗
PubMed1991

Tourette disorder and HLA typing.

HLA A, B, C and DR were typed in 73 Korean patients with Tourette disorder meeting the diagnostic criteria of DSM III-R and compared with 291 normal subjects. Relatively higher frequencies were found in HLA A11 and A26(10) with lower incidences in HLA A24(9) and B13. A family history of tic disorders was associated with a lower frequency of HLA A24(9).

Adolescent↗
PubMed1991

Effect of overcooked soybean meal on turkey performance.

Three turkey growth experiments were conducted to evaluate the effect of overcooked soybean meal (SBM) on BW gain and gain:feed ratio (FE). On two occasions soybean meals were custom prepared by changing the temperature and the retention time (RT) of the desolventizer-toaster unit at a commercial soybean processing plant. Three different meals were produced for each occasion mainly by altering RT from normal to approximately 1.35 and 2.43 times normal operating conditions (designated SBM1 to 3 on the first occasion and SBM4 to 6 on the second occasion). For SBM1 to 6, urease activities were .06, .00, .20, .01 and .00 delta pH, protein solubilities in .1 M borate at 40 C were 44, 45, 16, 44, 32, and 24%, and protein solubilities in .2% KOH were 86, 84, 76, 90, 85, and 85%, respectively. In two sequential long-term experiments, SBM1 to 3 were fed to turkeys from 0 to 8 wk, then a control (normal processing conditions, SBMF), was fed to the all treatment groups from 8 to 12 wk of age. The SBM4 to 6 were fed from 12 to 18 wk of age after rerandomizing treatment allocation of replicate pens. In the first trial, poults fed SBM3 showed significantly reduced BW gain from 3 wk on and a lower FE shown at 9 wk. No difference in BW gain and FE was observed in the trial from 12 to 18 wk. In a 15-day, short-term experiment starting with 3-day-old poults and feeding diets containing SBM2 to 6, BW gain and FE did not differ among treatment groups. It is concluded that SBM did not show a detrimental effect on turkey growth until it was overcooked by 2.4 times the normal conditions. The usual operating conditions in a commercial processing plant are well within the range for producing adequate SBM for poultry feed.

Animal Feed↗
PubMed1991

Human T-cell lymphotropic virus infection among blood donors in south Florida. The Transfusion Safety Study Group.

Knowledge of the epidemiologic pattern of human T-lymphotropic virus (HTLV) in the United States is being enlarged by blood donor screening. We tested stored sera from 29,937 donations made in South Florida in 1984-1985. Twenty-three donors were confirmed as seropositive, a prevalence of 0.8 per 1,000 donations. Specificity was supported by serologic retesting and virus culture of 11 donors located for follow-up. Sex- and age-specific prevalences did not differ significantly; blacks, however, accounted for 65% of seropositive donations. Within South Florida, one section of Miami had a prevalence of 4.5 per 1,000 donations, significantly above the 0.1 to 1.1 per 1,000 rates for other parts. An epidemiologic association with known HTLV-I endemic areas could account for most infections; all seven typed isolates were characterized as HTLV-I. Exposures, however, were diverse, sometimes multiple, and had no necessary relationship to personal lifestyle. This finding suggests that sources of infection were varied. Seropositive family members emphasize familial clustering of HTLV-I infection.

Adult↗
PubMed1991

Immune function and anti-HTLV-I/II status in anti-HIV-1-negative intravenous drug users receiving methadone.

PURPOSE: The study objective was to evaluate the effects of long-term methadone use and human T-cell leukemia virus (HTLV) types I and II seropositivity on the distribution of lymphocyte subsets and on lymphocyte function as measured in vitro in intravenous drug users seronegative for human immunodeficiency virus type 1 (HIV-1). PATIENTS AND METHODS: Anti-HIV-1-negative intravenous drug users receiving methadone maintenance therapy (n = 24) were studied in a Veterans Administration drug abuse treatment center. These subjects were compared to 38 age- and sex-matched control subjects who did not abuse drugs. HIV-1 and HTLV serostatus was determined by repetitive enzyme-linked immunosorbent assay and confirmed by immunoblot. Lymphocyte subsets were determined by two-color flow cytometry. Lymphocyte function was measured by proliferative response to plant mitogens and by natural killer (NK) cell-mediated cytotoxicity to a tumor cell target. RESULTS: Significant differences were seen in lymphocyte phenotype in the methadone-treated group, with elevations in the T-cell helper subset CD4+CD26+; in CD8 and CD8+I2+ cells, suppressor/cytotoxic T lymphocytes, and activated suppressor/cytotoxic T cells; and in CD2+CD26+ cells and activated total T lymphocytes. Lymphocyte function was suppressed in the methadone group, with poor responses to pokeweed mitogen and phytohemagglutinin in culture. Moreover, NK-cell cytotoxicity was significantly reduced in the methadone group. None of these immunologic differences were attributable to HTLV serostatus. CONCLUSION: The immune abnormalities seen suggest that a clinically significant degree of immune impairment exists in methadone-treated intravenous drug users. However, these abnormalities could not be explained by the presence of other retroviruses in this HIV-1-negative study group, as there was no significant difference in immune function when HTLV-seropositive patients were compared to HTLV-seronegative subjects treated with methadone.

Adult↗
PubMed1991

Vernal keratoconjunctivitis with shield ulcer--a case report.

This 9-year-old boy had a three-year history of vernal keratoconjunctivitis. A shield ulcer developed in the superior part of the cornea. The shield ulcer is a rare manifestation of the disease. Although the cause of shield ulcer is unknown, the association of shield ulcer with large papillae suggests a mechanical cause. The symptoms of itching and mucous discharge were relieved after medications with topical steroid and cromolyn sodium, but the large shield ulcer was persistent. The vernal ulcer was treated with a 72 hours collagen shield. The ulcer healed rapidly within 5 days, leaving a corneal opacity about the level of Bowman's layer.

Child↗
PubMed1991

Risk of human immunodeficiency virus type 1 infection among sexual and nonsexual household contacts of persons with congenital clotting disorders.

The status of human immunodeficiency virus type 1 (HIV-1) infection at the time of transmission to sexual contacts remains poorly defined. Transmission to nonsexual household contacts has appeared to be rare. A total of 505 sexual and nonsexual contacts of HIV-1-infected hemophiliacs in 349 households was observed. At entry, 10% of 201 sexual partners were anti-HIV-1-positive. Follow-up of 151 uninfected partners during a total of 351 person-years of observation showed no sero-conversions, although there were 13 pregnancies during that period. Eighty-seven percent of the seronegative respondents to a detailed questionnaire reported unprotected sexual contact at least occasionally. Among 304 other household members, including 108 parents who helped administer clotting factor concentrates to their children, none was seropositive at entry. Follow-up of 263 showed no seroconversions during a total of 605 person-years of observation. Thus, anti-HIV-1-positive hemophiliacs transmitted to their partners earlier in their course but were not found to do so when prospectively observed. No relationship to level of viremia as indicated by CD4 count, HIV-1 p24 antigenemia, or acquired immunodeficiency syndrome was found. Anti-HIV-1-positive hemophiliacs had not transmitted to their nonsexual household contacts before study entry and did not do so subsequently, indicating that the risk from even close nonsexual contact is extremely low.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Hematological indices in a cohort of HTLV-I/II and HIV-1 infected intravenous drug users in New York City.

The prevalence and clinical consequences of human T-cell lymphotropic viruses types I and II (HTLV-I/II) infection in human immunodeficiency virus-1 (HIV-1) infected persons are areas of continuing interest. This article reports the preliminary findings of the hematological indices in 454 patients infected with HIV-1 and HTLV-I/HTLV-II. Based on serology, 46.2% of the patients had evidence of HIV-1 infection only, 4.6% had evidence of HTLV-I/II only, 14.3% had evidence of both HIV-1 and HTLV-I/II, and 34.8% had evidence of neither HIV-1 or HTLV-I/II. The patient group with both HTLV-I/II and HIV-1 infection had lower total white blood cell, platelet, and serum hematocrits than patients with either HIV-1 or HTLV-I/II infection. While these differences were insignificant, they do not suggest any HTLV-I/II-induced protective effect against HIV-1 related hematological consequences.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Relationship of oscillatory potential amplitude to A-wave slope over a range of flash luminances in normal subjects.

The effect of flash luminance on the relationship of oscillatory potential (OP) amplitude, as a measurement of inner retinal function, to a-wave slope, as a measurement of photoreceptor function, was evaluated in full-field electroretinograms recorded from normal subjects. The ratio of OP amplitude to a-wave slope was found to be independent of flash luminance over a 3000-fold luminance range. This finding raises the possibility that a reduction in the ratio of OP amplitude to a-wave slope in eyes with media opacities may be used as a sign of inner retinal malfunction. Selected cases are presented to illustrate application of this approach.

Adult↗
PubMed1991

Seroepidemiology and clinical aspects of human T-cell lymphotropic virus type I/II infection in a cohort of intravenous drug users in New York City.

To define further the magnitude, epidemiology, and clinical features of human T-cell lymphotropic/leukemia virus type I/II (HTLV-I/II) infection in 454 intravenous drug users in New York City, we evaluated previously frozen aliquots of sera for HTLV-I/II antibodies using enzyme-linked immunoassay, Western blot, and radioimmunoprecipitation techniques. We found HTLV-I/II infection in 18.9% of the subjects. Age (p = 0.001), race (p = 0.001), having a same gender sexual relationship (p = 0.01), and HIV-1 infection (p = 0.041) were clear correlates of HTLV-I/II infection. HTLV-I/II seropositive subjects, in contrast to seronegative subjects, had lower leukocyte counts (p = 0.05) and higher globulin (p = 0.005) and gamma globulin (p = 0.009) levels even when HIV-1 serostatus was controlled. The considerable prevalence of HTLV-I/II infection and the morbidity of HTLV-I/II-associated disorders strongly suggest a continued need to define the dimensions of HTLV-I/II infection.

Adult↗
PubMed1990

Strategies for screening blood for human immunodeficiency virus antibody. Use of a decision support system.

A decision analytic model was used to examine alternative strategies to screen donated blood for human immunodeficiency virus (HIV) using data from the literature and from 1987 blood-screening programs in areas with high and low prevalence of HIV. Sensitivity analyses incorporated uncertainties about HIV infection and test performance. Current screening strategies are estimated to allow 20.5 infected units per million donated units to be transfused at a cost of $16,850 per HIV-positive unit detected in high-prevalence areas and 4.7 infected units per million donated units to be transfused at a cost of $32,275 per HIV-positive unit detected in low prevalence areas, with nine false-positive notifications of uninfected patients per million units screened and 14.9 discarded, noninfected units per HIV-positive unit in low-prevalence areas. Testing donated blood for HIV can be improved by individualizing screening strategies for areas with different prevalences of HIV. Efforts to further reduce transfusion-associated HIV should focus on improved test performance in early stages of infection, reduction of unnecessary transfusions, donor recruitment in lower-risk groups, and public health measures to reduce HIV infection among the general population.

Blood Donors↗
PubMed1990

Nucleotide sequence and DNA recognition elements of alc, the structural gene which encodes allantoicase, a purine catabolic enzyme of Neurospora crassa.

The nitrogen regulatory circuit of Neurospora crassa contains structural genes that encode nitrogen catabolic enzymes which are subject to complex genetic and metabolic regulation. This set of genes is controlled by nitrogen limitation, by specific induction, and by the action of nit-2, a major positive-acting regulatory gene, and nmr, a negative-acting control gene. The complete nucleotide sequence of alc, the gene that encodes allantoicase, a purine catabolic enzyme, is presented. The alc gene contains a single intron, is transcribed from two initiation sites situated approximately 50 nb upstream of the translation start site, and encodes a protein comprised of 354 amino acids. Mobility shift and DNA footprint experiments identified a single binding site for the NIT2 regulatory protein in the alc promoter region. The binding site contains a 10 nucleotide base pair symmetrical sequence which is flanked by two possible core binding sequences, TATCT and TATCG. Mutant NIT2/beta-gal fusion proteins with amino acid substitutions in a putative zinc-finger motif were shown to be completely deficient in the ability to bind to the alc promoter DNA fragment.

Amino Acid Sequence↗
PubMed1990

Age-, tissue-, and Ah genotype-dependent differences in the binding of 3-methylcholanthrene and its metabolite(s) to mouse DNA.

The induction of transplacental carcinogenesis by 3-methylcholanthrene (MC) in mice is determined, in part, by the genotype at the Ah locus. The relationship of Ah genotype and MC-induced DNA adducts was tested by comparing the response of pregnant and fetal C57BL/6 mice (Ahb Ahb; responsive to the induction of MC metabolism) and DBA/2mice (Ahd Ahd; nonresponsive). On day 17 of gestation (day 1 = presence of vaginal plug), C57BL/6 mice were treated i.p. with 100 mg/kg MC and DBA/2 mice with 30 mg/kg. Mice were sacrificed 24 h later and the tissues were analyzed for the presence of DNA adducts using the P1 nuclease version of the 32P-postlabeling method. With a 3.3-fold difference in administered dose, the total adduct levels in fetal DNA were (a) similar in both strains with the exception of liver, for which C57BL/6 mice had more adducts; (b) higher in the lung than skin, liver, or thymus; and (c) only 1/4 to 1/14 of the adult levels. Maternal DBA/2DNA contained more adducts in the thoracic lymph nodes and liver but fewer in the placenta and lung, compared to maternal C57BL/6 DNA. More adducts were detected in lung DNA than liver DNA in C57BL/6 mice. In contrast, these levels were similar in DBA/2 mice. When the difference in dose administered was considered in conjunction with this, less MC bound to DNA of C57BL/6 than DBA/2 mice overall. To identify adducts, oxidized metabolites of MC, 1-hydroxy-, 2-hydroxy-, 9,10-dihydrodiol-, or 3-methoxymethyl-MC, were topically applied to the dorsal skin of both strains. All of these metabolites produced adducts. Approximately 14 different adduct spots were detected. The two most abundant adducts were produced by 1-hydroxy-, 2-hydroxy-, and 9,10-dihydrodiol-MC. One of these also contained a 3-hydroxymethyl group. Several adducts did not contain the 9,10-dihydroxy group. The adducts derived from 3-methoxymethyl-MC were consistently found in greater abundance in DNA from C57BL/6 tissues, compared with DBA/2. Thus, oxidation of the 3-methyl group may be enhanced by Ah-dependent induction of MC metabolism. Together, these results suggest that the individual and total adduct levels are influenced by the genotype at the Ah locus, the route of administration, and the metabolite(s) with tissue and age specificity.

Animals↗
PubMed1990

Adult T-cell lymphoma in Israeli patients of Iranian origin.

The clinical and laboratory features of four Israeli patients with adult T-cell lymphoma-leukemia (ATL) are presented. In three of them evidence for human T-cell lymphotropic leukemia virus (HTLV-I) infection was obtained. Interestingly, all of the patients immigrated to Israel from the same regions in Iran. Except for lack of skin involvement, the clinical course was typical for ATL as described worldwide. This is the first report of ATL in an Iranian cohort. This observation suggests that Iranian patients with ATL-like illness should be studied for the presence of HTLV-I infection.

Aged↗
PubMed1990

Trifluoperazine binding to porcine brain calmodulin and skeletal muscle troponin C.

Binding of trifluoperazine (TFP), a phenothiazine tranquilizer, to porcine brain calmodulin (CaM) and rabbit skeletal muscle troponin C (Tn C) was measured by an automated high-performance liquid chromatography binding assay using a molecular sieving column; 10 micrograms of either protein per injection is sufficient for determining TFP binding, and results are comparable to those obtained by equilibrium dialysis. Very little binding was observed to either protein in the absence of Ca2+ while in the presence of Ca2+ both proteins bind 4 equiv of TFP. Other characteristics of TFP binding however are different for each protein. For CaM, half-maximal binding occurs at 5.8 microM TFP, the Hill coefficient is 0.82, and the fit of the data to the Scatchard equation is consistent with four independent TFP-binding sites. Binding of one melittin displaces two TFP from CaM. Thus, there are two recognizable classes of TFP-binding sites: those that are displaced by melittin and those that are not. TFP causes an increase in the Ca2+ affinity of CaM, and three Ca2+ must be bound to CaM for TFP binding to occur. The studies also yielded a measure of the intrinsic affinity of three of CaM's Ca2(+)-binding sites that is in agreement with previous reports. For troponin C, half-maximal binding occurs at 16 microM TFP, the Hill coefficient is 1.7, and the data best fit the Adair equation for four binding sites. The measured constants K1, K2, K3, and K4 were 2.5 X 10(4), 6.6 X 10(3), 5.8 X 10(5), and 2.0 X 10(5) M-1, respectively, in 1 mM Ca2+ and were similar when Mg2+ was additionally included. TFP also increases troponin C's Ca2+ affinity, and it is the low-affinity, Ca2(+)-specific binding sites that are affected. These studies yielded a measure of the intrinsic affinity of these Ca2(+)-binding sites that is in agreement with previous measurements.

Animals↗
PubMed1990

Molecular cloning and characterization of alc the gene encoding allantoicase of Neurospora crassa.

Purines can be utilized as a secondary nitrogen source by Neurospora crassa during conditions of nitrogen limitation. The expression of purine catabolic enzymes is governed by the nitrogen regulatory circuit and requires induction by uric acid. The major positive-acting nitrogen regulatory gene, nit-2, turns on the expression of the purine catabolic enzymes, which may also be subject to negative regulation by a second control gene, nmr. We have cloned alc, the structural gene which encodes allantoicase, an inducible enzyme of the purine degradative pathway. The identity of the alc clone was confirmed by restriction fragment length polymorphism analysis and by repeat-induced mutation. The alc gene is transcribed to give a single messenger RNA, approximately 1.2 kb in length. The negative-acting nmr gene affects the expression of alc in the expected manner. Both the nit-2 and the nmr control genes affect alc mRNA levels and allantoicase enzyme activity in both the induced and nitrogen-repressed conditions.

Blotting, Northern↗