Evaluation of treatment outcomes for patients on first-line regimens in US President's Emergency Plan for AIDS Relief (PEPFAR) clinics in Uganda: predictors of virological and immunological response from RV288 analyses.

OBJECTIVES: Viral load (VL) monitoring is recommended, but seldom performed, in resource-constrained countries. RV288 is a US President's Emergency Plan for AIDS Relief (PEPFAR) basic programme evaluation to determine the proportion of patients on treatment who are virologically suppressed and to identify predictors of virological suppression and recovery of CD4 cell count. Analyses from Uganda are presented here. METHODS: In this cross-sectional, observational study, patients on first-line antiretroviral therapy (ART) (efavirenz or nevirapine+zidovudine/lamivudine) from Kayunga District Hospital and Kagulamira Health Center were randomly selected for a study visit that included determination of viral load (HIV-1 RNA), CD4 cell count and clinical chemistry tests. Subjects were recruited by time on treatment: 6-12, 13-24 or >24 months. Logistic regression modelling identified predictors of virological suppression. Linear regression modelling identified predictors of CD4 cell count recovery on ART. RESULTS: We found that 85.2% of 325 subjects were virologically suppressed (viral load<47 HIV-1 RNA copies/ml). There was no difference in the proportion of virologically suppressed subjects by time on treatment, yet CD4 counts were higher in each successive stratum. Women had higher median CD4 counts than men overall (406 vs. 294 cells/µL, respectively; P<0.0001) and in each time-on-treatment stratum. In a multivariate logistic regression model, predictors of virological suppression included efavirenz use [odds ratio (OR) 0.47; 95% confidence interval (CI) 0.22-1.02; P=0.057], lower cost of clinic visits (OR 0.815; 95% CI 0.66-1.00; P=0.05), improvement in CD4 percentage (OR 1.06; 95% CI 1.014-1.107; P=0.009), and care at Kayunga vs. Kangulamira (OR 0.47; 95% CI 0.23-0.92; P=0.035). In a multivariate linear regression model of covariates associated with CD4 count recovery, time on highly active antiretroviral therapy (ART) (P<0.0001), patient satisfaction with care (P=0.038), improvements in total lymphocyte count (P<0.0001) and haemoglobin concentration (P=0.05) were positively associated, whereas age at start of ART (P=0.0045) was negatively associated with this outcome. CONCLUSIONS: High virological suppression rates are achievable on first-line ART in Uganda. The odds of virological suppression were positively associated with efavirenz use and improvements in CD4 cell percentage and total lymphocyte count and negatively associated with the cost of travel to the clinic. CD4 cell reconstitution was positively associated with CD4 count at study visit, time on ART, satisfaction with care at clinic, haemoglobin concentration and total lymphocyte count and negatively associated with age.

Normal luminal bacteria, especially Bacteroides species, mediate chronic colitis, gastritis, and arthritis in HLA-B27/human beta2 microglobulin transgenic rats.

Genetic and environmental factors are important in the pathogenesis of clinical and experimental chronic intestinal inflammation. We investigated the influence of normal luminal bacteria and several groups of selected bacterial strains on spontaneous gastrointestinal and systemic inflammation in HLA-B27 transgenic rats. Rats maintained germfree for 3-9 mo were compared with littermates conventionalized with specific pathogen-free bacteria. Subsequently, germfree transgenic rats were colonized with groups of five to eight bacteria that were either facultative or strictly anaerobic. Transgenic germfree rats had no gastroduodenitis, colitis, or arthritis, but developed epididymitis and dermatitis to the same degree as conventionalized rats. Colonic proinflammatory cytokine expression was increased in transgenic conventionalized rats but was undetectable in germfree and nontransgenic rats. Colitis progressively increased over the first 4 wk of bacterial exposure, then plateaued. Only transgenic rats colonized with defined bacterial cocktails which contained Bacteroides spp. had colitis and gastritis. Normal luminal bacteria predictably and uniformly induce chronic colonic, gastric and systemic inflammation in B27 transgenic F344 rats, but all bacterial species do not have equal activities.

Transplantation of insulin-like growth factor-II-secreting tumors into nude rodents.

Restricted supplies of insulin-like growth factor II (IGF-II) have severely limited investigation of the in vivo actions of this hormone. To circumvent this problem, we have developed an in vivo rodent model in which rat (r) IGF-II-secreting cells (18, 54-SF) are transplanted into congenitally immunodeficient (nude) rats and mice. These cells proliferate and form discrete tumors that contain rIGF-II and abundant IGF-II receptors. The tumors also secrete rIGF-II into the circulation, resulting in plasma rIGF-II concentrations many-fold greater than those in control rodents (81 +/- 19 vs. less than 10 ng/ml, rats; 159 +/- 28 vs. 18 +/- 5 ng/ml, mice; P less than 0.05, both groups). There was no significant difference between the tumor-bearing and control rodents in either body weight or tail length. The tumor-bearing rodents did have significantly lower concentrations of IGF-I (296 +/- 23 vs. 527 +/- 67 ng/ml, rats; 300 +/- 26 vs. 482 +/- 70 ng/ml, mice; P less than 0.05, both groups), suggesting that the increased concentrations of rIGF-II may have inhibited IGF-I production or secretion. This animal model may be used to explore the biological effects of increased plasma IGF-II concentrations.

Effects of gender and social behavior on the development of coronary artery atherosclerosis in cynomolgus macaques.

This experiment involved examination of the effects of gender and social status ('competitive dominance') on the coronary artery atherosclerosis of cynomolgus monkeys. Thirty-two adult Macaca fascicularis (16 males, 16 females) were fed a diet containing a moderate amount of cholesterol (0.56 mg/cal) for 16 months. The monkeys were housed in groups of 4 animals of the same sex, and all groups were stable in composition for the entire experiment. After 1 year a'competitive dominance' score was determined for each monkey, based on feeding order in 9 trials involving a preferred food as incentive. At necropsy the coronary arteries were pressure perfused; 5 sections each were then taken from the left anterior descending, left circumflex and right coronary arteries. For each animal, the mean percent lumen stenosis calculated from theses 15 sections was used as the index of extent of coronary artery atherosclerosis. Males had significantly more extensive coronary artery atherosclerosis than did females. Further, among both males and females, submissive animals (low in competitiveness) had more extensive coronary artery stenosis than did their dominant (highly competitive) counterparts. A similar pattern was observed in the thoracic and abdominal portions of the aorta with respect to competitiveness, but not gender. In the iliac artery, females had less atherosclerosis than males but there was no competitiveness effect. The gender and social status effects on atherosclerosis were each statistically independent of variability in clinical-pathological measures (serum lipid concentrations and heart weight). The results indicated that: (a) gender and psychosocial stress independently affect the development of coronary artery atherosclerosis; (b) the mechanisms mediating these effects remain unknown; and (c) the cynomolgus macaque is a good model for the study of such phenomena.

Effects of elevated serum insulinlike growth factor-II on growth hormone and insulinlike growth factor-I mRNA and secretion.

The insulinlike growth factors (IGF) appear to exert feedback control over their own production. In an effort to determine the physiologic mechanisms for this feedback modulation, we utilized a previously developed in vivo model in which rIGF-II secreting tumor cells are transplanted into immunodeficient rats to form IGF-II secreting tumors. The tumor-bearing rat have serum IGF-II concentrations sevenfold greater than those in controls (119 +/- 16 ng/mL [mean +/- SE] v 17 +/- 2 ng/mL, P less than .0001). Serum IGF-I concentrations were reduced among the tumor-bearing rats (438 +/- 42 ng/mL v 606 +/- 32 ng/mL, P = .002) and were negatively correlated with IGF-II concentrations (r = -.47, P = .025), suggesting that IGF-II suppressed the secretion of IGF-I. Increased serum IGF-II concentrations, however, did not affect basal growth hormone concentrations (tumor-bearing, 44 +/- 12 ng/mL; control 33 +/- 6 ng/mL, P = 0.96). The GH response to GH releasing factor was likewise similar in both groups. Moreover, pituitary GH mRNA level were not different in the two groups, suggesting that IGF-II does not have a significant effect on GH secretion in this in vivo model. There was no association between serum glucose and serum IGF-I or IGF-II concentrations. To examine the effect of IGF-II on IGF-I production from the liver, we measured IGF-I mRNA levels in a subset of animals. Despite these differences in serum IGF-I concentrations, the tumor-bearing rats did not have significantly lower liver IGF-I mRNA levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of chromic oxide, glycerol triether, and beta-sitosterol as fecal flow markers in two species of nonhuman primates.

Recovery of beta-sitosterol, glycerol triether (1-hexadecyl-2,3-didodecyl glycerol triether), and chromic oxide was studied in African green monkeys and stumptail macaques consuming diets containing 0.75 mg/Cal cholesterol and 38% of calories as safflower oil or butter. Following oral administration of these compounds, feces were collected daily for 9 days. For all animals, excretion of beta-sitosterol and glycerol triether paralleled one another almost exactly. Except for two animals, this was also true for chromic acid. Essentially 100% of the administered beta-sitosterol and 90-95% of the glycerol triether were recovered; excretion of these markers virtually was complete by day 3. Ninety-two percent of the beta-sitosterol was isolated in the nonsaponifiable lipid extract of the feces with less than 6% in the remaining aqueous phase. A maximum of 3.1% of the beta-sitosterol and 1.8% of the glycerol triether were found in the blood. For stumptail macaques, the major excretory form of beta-sitosterol was the 5 beta-derivative. African green monkeys were more variable; one animal excreted the bulk of the beta-sitosterol unchanged while others excreted greater than 80% as the ring-saturated 5 beta-derivative. Animals consuming the safflower oil containing diet consistently excreted a greater percentage of the beta-sitosterol unchanged, compared with those animals eating the butter containing diet. There was no evidence for steroid ring degradation in any of the animals used in this study.

Differences in the microenvironment of a polycarbonate caging system: bedding vs raised wire floors.

The microenvironment of polycarbonate cages housing rats with and without various types of bedding was compared with that of cages that utilized wire floor inserts with different bedding types. Parameters monitored were temperature, humidity, ammonia concentrations and particulates. No differences were noted in the various caging types in relation to temperature and humidity measurements. Significant differences in ammonia concentrations existed in some of the cages when bedding material was used. The use of raised floorwalk inserts also demonstrated significant differences in particulate counts to cages without inserts. The data obtained demonstrated that contact bedding was useful in controlling ammonia generation and that a raised floorwalk insert reduced significantly the aerosolization of bedding particles that could be ingested or inhaled by the rats.

An evaluation of a water purification system for use in animal facilities.

A commercially available water purification system was evaluated for its ability to minimize chemical and microbial contaminants. The reduction or removal of these impurities from the drinking water of experimental animals would reduce experimental variability. 3 strains of bacteria were collected from the processed water. An increase in the total number of bacteria was observed the longer the filters remained in use. Determinations of heavy metals in water samples before and after processing were made for lead, zinc, copper, nickel, manganese, iron, arsenic and mercury. Calcium and magnesium levels were also determined. The concentrations of these inorganic chemicals were reduced by the purification process except at 2 time points in which desorption of the chemical could have occurred. Bacterial colonization and desorption of these chemicals were controlled by installing new filter cartridges. Volatile halocarbon concentrations were determined for water samples before and after purification. All volatile halocarbons analyzed were less than 10 ppb before and after purification at all time points. Other organic chemicals were greatly reduced by the purification process. In a study of contaminants associated with installation of the unit, it was found that flushing the unit for 8 days reduced lead and methyl ethyl ketone concentrations to insignificant levels. The purification system was found to be effective in providing high quality drinking water as verified by a microbial and chemical testing program.

Naturally occurring tuberculosis in a squirrel monkey and a cebus monkey.

Tuberculosis was detected in a Brazilian squirrel monkey (Saimiri sciureus) and in a cebus monkey (Cebus apella). Both of these animals were housed in the same room with a rhesus monkey (Macaca mulatta) subsequently found to be tuberculous. All 3 of the monkeys died within a 4-month period.