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T Frederick

Publications and source records attributed to T Frederick.

13 recordsLinked to original sources
PubMed2000

Epidemiology of human immunodeficiency virus-associated opportunistic infections in the United States in the era of highly active antiretroviral therapy.

The incidence of nearly all AIDS-defining opportunistic infections (OIs) decreased significantly in the United States during 1992-1998; decreases in the most common OIs (Pneumocystis carinii pneumonia ¿PCP, esophageal candidiasis, and disseminated Mycobacterium avium complex ¿MAC disease) were more pronounced in 1996-1998, during which time highly active antiretroviral therapy (HAART) was introduced into medical care. Those OIs that continue to occur do so at low CD4+ T lymphocyte counts, and persons whose CD4+ counts have increased in response to HAART are at low risk for OIs, a circumstance that suggests a high degree of immune reconstitution associated with HAART. PCP, the most common serious OI, continues to occur primarily in persons not previously receiving medical care. The most profound effect on survival of patients with AIDS is conferred by HAART, but specific OI prevention measures (prophylaxis against PCP and MAC and vaccination against Streptococcus pneumoniae) are associated with a survival benefit, even when they coincide with the administration of HAART. Continued monitoring of incidence trends and detection of new syndromes associated with HAART are important priorities in the HAART era.

AIDS-Related Opportunistic Infections↗
PubMed2000

Human immunodeficiency virus-infected adolescents: a descriptive study of older children in New York City, Los Angeles County, Massachusetts and Washington, DC.

BACKGROUND: Children infected with HIV are entering adolescence with challenging and changing medical and social needs. Through chart review we describe certain medical and social characteristics of adolescents who acquired HIV as children. METHODS: HIV-infected children 12 years of age and older in 1995 were monitored through the Pediatric Spectrum of HIV Disease study from four US sites. In addition to standard 6-month medical chart reviews, a special chart abstraction in 1997 collected available psychosocial and sexual history information. RESULTS: A total of 131 adolescents HIV-infected as children were studied: 52 infected perinatally; 44 infected through a contaminated blood transfusion; 30 through receipt of contaminated blood products for hemophilia; and 5 with unknown transmission mode. Mean age at last medical contact was 15.5 years, 67% were Hispanic or African-American, 12% were employed, 66% attended regular school, 66% knew their HIV status and 48% (8% for the perinatally infected) lived with their biologic mother. Information on sexual activity showed that 18% had sexual relations, 28% did not and for 53% sexual activity was not recorded in the medical chart. Four percent used illicit drugs, which along with sexual activity showed a positive association with age. Forty-two percent had an AIDS-defining opportunistic infection, and 56% had a recent CD4+ lymphocyte count <200 cells/microl. CONCLUSIONS: Adolescents in this study represent a heterogeneous group of surviving HIV-infected children some of whom are sexually active and potential sources of HIV transmission. Clinicians who treat HIV-infected and high risk adolescents face the challenges of providing care and prevention services appropriate to adolescent development.

Adolescent↗
PubMed2000

Lack of definitive severe mitochondrial signs and symptoms among deceased HIV-uninfected and HIV-indeterminate children < or = 5 years of age, Pediatric Spectrum of HIV Disease project (PSD), USA.

BACKGROUND: In response to recent reports of mitochondrial dysfunction in HIV-uninfected infants exposed to antiretroviral (ARV) prophylaxis, the Perinatal Safety Review Working Group reviewed deaths in five large HIV-exposed perinatal cohorts in the United States to determine if similar cases of severe mitochondrial toxicity could be detected. We describe the results of this review for the PSD cohort. METHODS: Hospitalization, clinic and death records for deceased HIV-uninfected and HIV-indeterminate children who were less than 5 years of age were reviewed. Standard definitions were used to classify HIV infection status and the likelihood that signs and symptoms were related to mitochondrial dysfunction. Children were classified as having signs and symptoms that were considered (1) unrelated, (2) unlikely, (3) consistent with, or (4) likely related to mitochondrial disease. SIDS deaths were put into a separate category. RESULTS: 8,465 of 13,125 HIV-exposed children were either HIV-uninfected or HIV-indeterminate. Among the 84 deaths in the subgroup of 8,465 children, 9 were considered in Class 2 (unlikely), 4 were considered in Class 3 (consistent with), and none were considered in Class 4 (likely). 97% of those children who received ARV prophylaxis received zidovudine alone. None of the HIV-uninfected deaths were classified in 2, 3, or 4; and only one of these was exposed to ARV prophylaxis. Among the 3 HIV-indeterminate children who were classified in 3 (consistent with), 2 had no or unknown ARV exposure before 1994 when use of ZDV prophylaxis became the standard of care. Both HIV-uninfected and HIV-indeterminate children with ARV exposure or unknown exposure had lower mortality rates than children without ARV exposure. CONCLUSION: Monoprophylaxis with ZDV was not associated with higher death rates in the cohort of 8,465 children or with any findings likely consistent with mitochondrial dysfunction among the 85 deaths. Ongoing monitoring of drug safety in large multi-site prospective cohort studies of HIV-exposed children is essential in the era of highly active antiretroviral therapy.

Acquired Immunodeficiency Syndrome↗
PubMed1997

A descriptive survey of pediatric human immunodeficiency virus-infected long-term survivors.

OBJECTIVE: To identify the population of human immunodeficiency virus-infected pediatric long- term survivors (LTS) followed in major medical institutions in California, Florida and New Jersey. METHODS: A cross-sectional survey was performed with data collection forms sent to all investigators. Demographic, clinical, and laboratory data were obtained on all living patients >/=8 years infected in the perinatal period with human immunodeficiency virus. RESULTS: A total of 143 perinatally infected and 54 children infected by neonatal transfusion were identified. Fifty-four children (27%) had absolute CD4 counts >/=500 cells/mm (group 1: mean age 9.8 years), 54 children (27%) had CD4 counts between 200 and 500 cells/mm (group 2: mean age 10.1 years), and 89 children (45%) had CD4 counts <200 cells/mm (group 3: mean age 10.4 years). Ninety-five (48%) patients had developed AIDS defining conditions; 14 (26%) in group 1, 26 (48%) in group 2, and 55 (62%) in group 3. Ninety-two percent of patients had received antiretrovirals. Perinatally human immunodeficiency virus-infected children tended to be younger (mean age 9.8 years) than children infected via a blood transfusion (mean age 11 years). Generalized lymphadenopathy was the most prevalent clinical finding. Lymphoid interstitial pneumonia and recurrent bacterial infections were the most prevalent acquired immune deficiency syndrome-defining conditions. Twenty percent of LTS had CD4 counts >/=500 cells/mm and no immune deficiency syndrome-defining conditions. CONCLUSIONS: Pediatric LTS were in variable stages of disease progression. The proportion of children within each CD4 strata did not differ by mode of acquisition of infection. Increased CD4 counts were inversely proportional to age. Only 20% of pediatric LTS had minimal to no disease progression.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Frequent recurrence and persistence of varicella-zoster virus infections in children infected with human immunodeficiency virus type 1.

OBJECTIVE: To examine complications and treatment of varicella-zoster virus (VZV) infections in children infected with human immunodeficiency virus type 1 (HIV-1). METHODS: Cases of VZV infection were identified retrospectively by reports to the department of health services and review of medical charts. The CD4+ cell counts were correlated with severity and frequency of VZV episodes. RESULTS: We identified 117 episodes of VZV infection in 73 HIV-1-infected children between Aug. 21, 1986, and Dec. 1, 1993. The most common complications were recurrence and persistence; 38 children (53%) had 69 recurrent episodes of VZV infection. The majority of children (61%) had zoster during the first recurrent episode, and 32% had a disseminated eruption typical of varicella. There was a strong association between an increasing number of episodes of VZV infection and low CD4+ cell count (p = 0.0008). In a subgroup followed for at least 2 years after their primary varicella episode, 10 of 22 children had a recurrence. Persistence of VZV infection was documented in 10 of 73 children, whereas other complications were rare. Thirty-three children (45%) were hospitalized and received acyclovir intravenously. CONCLUSION: Primary, recurrent, and persistent VZV infections are a frequent cause of morbidity and hospitalization for HIV-1-infected children. Studies of improved preventive and therapeutic agents are urgently needed in this population.

AIDS-Related Opportunistic Infections↗
PubMed1995

Evaluation of recombinant human factor IX: pharmacokinetic studies in the rat and the dog.

The pharmacokinetics of intravenously administered recombinant human factor IX (rhFIX) were studied in Sprague-Dawley rats and Beagle dogs. Rats received rhFIX (50 IU/kg once daily) for 28 days, and the plasma half-life was 5 h. Anti-Human Factor IX serum antibody levels were found in only 1 of 12 rats. The pharmacokinetic profiles of rhFIX or Mononine, a purified human plasma-derived factor IX, after single 100 IU/kg i.v. doses in dogs, were similar. Peak plasma concentrations of rhFIX and Mononine were 4-5 micrograms/ml. The mean plasma half-lives were 13.2 +/- 1.6 h for rhFIX and 13.3 +/- 1.6 h for Mononine. Dogs also received rhFIX (40 IU/kg i.v., daily) for 28 days or Mononine (40 IU/kg i.v. daily) for 14 days. Anti-human Factor IX serum antibody levels were determined for each compound. Pharmacokinetic half-lives decreased in these treated dogs which developed antihuman Factor IX antibodies. The antibody responses in 28 day rhFIX (40 IU/kg) dogs were similar to 14 day Mononine (40 IU/kg) dogs.

Animals↗
PubMed1994

Progression of human immunodeficiency virus disease among infants and children infected perinatally with human immunodeficiency virus or through neonatal blood transfusion. Los Angeles County Pediatric AIDS Consortium and the Los Angeles County-University of Southern California Medical Center and the University of Southern California School of Medicine.

Using community-based surveillance data for pediatric human immunodeficiency virus (HIV) infection, we examined disease progression using survival analysis among perinatally HIV-infected children and children HIV-infected through a neonatal blood transfusion. As of December 31, 1991, 238 HIV-infected children (classified P-1 or P-2 according to the Centers for Disease Control and Prevention classification system) were identified. Median symptom-free survival time from birth to symptomatic infection (P-2) was different for perinatally acquired (n = 166) and neonatal transfusion-acquired (n = 72) infection (6.4 months vs. 17.8 months, respectively; P < 0.001). Survival after development of symptomatic infection (P-2) did not differ by transmission mode. Survival differences from birth to death were significant at P < 0.05 (75% of perinatally HIV-infected children survived 44 months vs. 71 months for transfusion-associated children). Although survival estimates improved for those receiving antiretroviral treatment, differences by mode were still observed. For perinatally HIV-infected children, mortality was highest in the first year of life (12%). Those remaining symptom-free beyond their first year demonstrated survival experiences similar to those for children with transfusion-associated infection.

AIDS Serodiagnosis↗
PubMed1992

The readers' NIH.

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Biological Science Disciplines↗
PubMed1991

CD4 T-lymphocyte counts and Pneumocystis carinii pneumonia in pediatric HIV infection.

The relationship between CD4 T-lymphocyte counts and infection with the human immunodeficiency virus (HIV) is retrospectively investigated for 266 HIV-infected and uninfected children who were born to infected women, including 39 with Pneumocystis carinii pneumonia (PCP), in a population-based surveillance study. Of 21 perinatally HIV-infected children with PCP only 10 (48%) had CD4 T-lymphocyte counts that were less than 500 x 10(6) cells/L (500 cells/mm3), compared with all 18 who were infected via blood transfusions or clotting factors. Among 68 children who were 1 year or younger, 18 (90%) of 20 PCP cases had CD4 T-lymphocyte counts that were less than 1500 x 10(6) cells/L (1500 cells/mm3) compared with only five (10%) of 48 children who did not have the acquired immunodeficiency syndrome (odds ratio, 77.4; 95% confidence interval, 19.7 to 313.4). The mean CD4 T-lymphocyte count was lower for the 39 PCP cases when compared with the 188 children who were at different stages of HIV infection and did not have the acquired immunodeficiency syndrome (AIDS) independent of age. The majority of perinatally HIV-infected children with PCP were 6 months or younger and 50% were previously unknown to be infected. Thus, HIV-positive children should be identified early and followed closely. CD4 T-lymphocyte counts may be useful in monitoring HIV-positive children and determining when to begin PCP prophylaxis.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Citric acid treatment of periodontitis-affected cementum. A scanning electron microscopic study.

Previous studies have described an inconsistent histological occurrence of a zone of surface demineralization on periodontitis-affected cementum following treatment with citric acid, and a lack of connective tissue attachment to the latter surfaces. In view of these findings, the purpose of the present study was to use scanning electron microscopy to examine the surface morphology of cementum from normal and periodontitis-affected root surfaces following citric acid treatment for differences in the effects of the demineralizing solution on these surfaces. Cementum surfaces were derived from the roots of extracted human teeth from areas beneath attached periodontal ligament fibers (normal) and calculus deposits (periodontitis-affected). 5 specimens were evaluated in both groups. Periodontal ligament fibers were removed from normal root surfaces with a curette, and calculus deposits were removed from periodontitis-affected root surfaces using an ultrasonic scaler. The resultant 5 specimens in each group were then sectioned in half, one-half serving as the untreated control and the other as the experimental, citric acid treated specimen. Experimental specimens were immersed in a saturated solution of citric acid, pH 1 for 3 min and then rinsed in tap water. Both control and experimental specimens were dehydrated in ethanol, critical-point dried, sputter-coated with gold and examined in the scanning electron microscope for morphological characteristics. Citric acid treatment of cementum from normal root surfaces produced an undulating, markedly fibrillar surface morphology which is consistent with the exposure of a fibrillar, collagen substrate. Periodontitis-affected cementum, however, was not appreciably altered in appearance by the citric acid treatment, having only a faint mat-like surface texture. (ABSTRACT TRUNCATED AT 250 WORDS)

Citrates↗
PubMed1988

Personal health habits and symptoms of depression at the community level.

This investigation examined the relationship between lifestyle, as defined by common health habits, and symptoms of depression in a general community sample. The study was conducted using data from a longitudinal survey involving four interviews of 1,003 Los Angeles County adults. The survey focused on the epidemiology of depression and help-seeking behavior, which included questions about seven health habits identified in the Alameda County Study as predictive of health status. The group used for this analysis comprised 752 adults who participated in and had usable depression scores (as measured with the 20-item CES-D scale) at all interviews. Depression prevalence rates were higher for six of the seven "poor" health habits examined compared with the "good" health habit. Prevalence odds ratios were greater than 2.0 for poor sleeping and drinking habits (both sexes) and equaled 1.8, among women only, for poor physical activity and smoking habits. Multivariate regression analyses showed a simple sum of the total number of good habits to be a significant independent predictor of depression after controlling for prior depression and various sociodemographic factors. The finding of an independent contribution of health habits to depression status emphasizes that lifestyle may influence mental as well as physical health.

Adult↗
PubMed1975

Passive immunity in transmissible gastroenteritis of swine: intramuscular injection of pregnant swine with a modified live-virus vaccine.

Nine pregnant swine were intramuscularly injected with a modified live-virus transmissible gastroenteritis (TGE) vaccine at approximately 6 and 2 weeks before parturition. The TGE antibody levels in milk whey rapidly decreased within a few days after parturition, and the antibodies were mainly, if not solely, of the immunoglobulin G (IgG) class. Nursing newborn pigs were challenge exposed with virulent TGE virus when 2 to 4 days old. All pigs in 8 of the 9 litters became affected with typical signs of TGE. Of the pigs nursing vaccinated sows, 55% died, and of the 9 vaccinated sows, 8 became affected after challenge exposure of their litters. Subsequently, the antibody titers in serum and milk markedly increased in all 9 sows, with the antibody in milk being predominantly of the immunoglobulin A (IgA) class. Serum samples of prenursing newborn pigs from vaccinated sows did not contain detectable TGE antibodies. The capability of the vaccinated sows to provide only limited passive immunity to their suckling pigs was considered to be due mainly to the low titer and class (IgG) of TGE antibody existing in the milk of the sows at the time the newborn pigs were challenge exposed.

Animals↗