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S R Ostrowski

Publications and source records attributed to S R Ostrowski.

17 recordsLinked to original sources

Elevated plasma urokinase receptor predicts low birth weight in maternal malaria.

The blood level of soluble urokinase receptor (suPAR) is increased and associated with a poor clinical or fatal outcome in children with acute malaria. This study hypothesized that the suPAR level would be associated with foetal outcome in maternal malaria. suPAR was measured by ELISA in maternal and cord plasma samples taken during delivery in 253 pregnant Kenyan women stratified according to placental histology: no malaria infection (non-infected), active or active-chronic infection (actively infected) or past-chronic infection (past-infected). Maternal-suPAR was higher in actively infected women (median 3.93 (IQR 2.92-5.29) ng/mL) compared with non-infected (median 2.78 (IQR 1.86-3.87) ng/mL, P = 0.001) and past-infected (median 2.67 (IQR 1.94-3.7) ng/mL, P = 0.012) women. Cord-suPAR was comparable across the groups (median 2.98 (IQR 2.38-3.77) ng/mL). In actively infected women, maternal-suPAR and gestational age were the only independent predictors of birth weight in multivariate linear regression adjusted for maternal-suPAR, HIV-1 infection, age, BMI, haemoglobin, peripheral parasitaemia, parity and gestational age; 1 ng/mL higher maternal-suPAR predicted -56 g (95% CI -100 to -12, P = 0.016) reduced birth weight. Cord-suPAR could not predict birth weight after adjusting for gestational age. Future studies are warranted to investigate whether the maternal suPAR level is increased earlier in pregnancy in women with active placental malaria infection and whether early maternal suPAR measurements can predict birth weight. If so, measurements of maternal suPAR early in pregnancy might then potentially identify women with increased needs for antenatal care and intervention.

Adult↗

Elevated levels of soluble urokinase receptor in serum from mycobacteria infected patients: still looking for a marker of treatment efficacy.

In search for a serological marker, which may be used to monitor treatment efficacy in patients with extra-pulmonary mycobacterial infections, serum samples were collected prospectively from patients during a 6-months treatment period. The levels of soluble urokinase-type plasminogen activator receptor (suPAR) and soluble tumour necrosis factor receptor II (sTNFrII) were measured and compared with erythrocyte sedimentation rate (SR) and C-reactive protein levels (CRP). sTNFrII levels were elevated at the time of diagnosis and declined in parallel with traditional inflammation markers (SR and CRP). suPAR levels were elevated to more than double (median 7.7 ng/ml, range 5.6-25.8) compared to levels previously reported for patients with pulmonary tuberculosis. The serum suPAR levels however remained high during the entire treatment period. This may reflect that significant inflammatory activity is continuing for more than 6 months in patients with extrapulmonary mycobacterial infections, despite adequate anti-tuberculosis treatment.

Adult↗

Plasma levels of intact and cleaved urokinase receptor decrease in HIV-1-infected patients initiating highly active antiretroviral therapy.

Elevated blood levels of soluble urokinase receptor (suPAR) measured by ELISA decrease in human immunodeficiency virus-1 (HIV-1)-infected patients initiating highly active antiretroviral therapy (HAART). As the suPAR ELISA measures both three- and two-domain suPAR [suPAR(I-III), suPAR(II-III)] and suPAR(I-III)-ligand complexes, the amount by which the individual suPAR forms (suPAR(I-III), suPAR(II-III) and one-domain suPAR [suPAR(I)]) decrease in plasma in HIV-1-infected patients initiating HAART is unknown. Consequently, the objective of this study was to investigate HAART-induced changes in the individual plasma suPAR forms in HIV-1-infected patients. Plasma suPAR was measured by three time-resolved fluorescence immunoassays detecting suPAR(I-III), suPAR(I-III) + suPAR(II-III) and suPAR(I) in 29 treatment-naïve HIV-1-infected patients followed annually for 5 years after initiation of HAART and in 20 age- and gender-matched healthy individuals. In addition, plasma levels of the following inflammatory markers were also investigated: soluble tumour necrosis factor receptor (sTNFr)-II, TNF-alpha, interleukins (IL)-10, IL-6, IL-4, IL-2 and interferon (IFN)-gamma. In HIV-1-infected patients, plasma suPAR(I-III), suPAR(II-III) and suPAR(I) decreased within the first treatment year (all P < 0.05) and suPAR(I-III) and suPAR(II-III) remained above normal throughout follow-up (both P < 0.05). Plasma sTNFrII, IL-6, IFN-gamma and IL-10 also decreased during HAART (all P < 0.05). In HIV-1-infected patients, sTNFrII correlated with all suPAR forms before (all P < 0.01) and after 5 years HAART (all P < 0.001), whereas sTNFrII and suPAR did not correlate in healthy individuals. Intact and cleaved plasma suPAR decreased in HIV-1-infected patients initiating HAART but remained above normal. The positive correlation with sTNFrII suggests that the individual plasma suPAR forms are linked to immune activation in HIV-1 infection.

Adult↗

Interleukin-6 infusion during human endotoxaemia inhibits in vitro release of the urokinase receptor from peripheral blood mononuclear cells.

Leucocyte expression of the urokinase receptor [urokinase-type plasminogen activator receptor (uPAR)] is regulated by inflammatory mediators. This study investigated the in vivo effect of endotoxin, interleukin (IL)-6 and tumour necrosis factor (TNF)-alpha on uPAR-release in vivo and in vitro in humans. Healthy subjects received intravenous endotoxin injection [high-dose, 2 ng/kg (n=8) and low-dose, 0.06 ng/kg (n=7)], coadministration of 0.06 ng/kg endotoxin and 3 h recombinant human (rh)IL-6 infusion (n=7) or 3 h infusion of rhIL-6 (n=6), rhTNF-alpha (n=6) or NaCl (n=5). Soluble uPAR (suPAR) was measured by enzyme-linked immunosorbent assay in plasma and supernatants from unstimulated and phytohaemagglutinin and lipopolysaccharide-stimulated peripheral blood mononuclear cell (PBMC) cultures incubated for 24 h. The spontaneous and stimulated uPAR-release from PBMC cultures was enhanced 5 h after low-dose endotoxin (both P <0.05), but coadministration of rhIL-6 during low-dose endotoxaemia abolished this enhanced uPAR release. High-dose endotoxin increased plasma suPAR levels (P <0.001) whereas low-dose endotoxin, rhIL-6 or TNF-alpha did not influence uPAR release in vivo to such degree that a systemic effect on the plasma suPAR level was detectable. Even subclinical doses of endotoxin in vivo enhance the capacity of PBMC to release uPAR after incubation in vitro. The inhibitory effect of IL-6 on endotoxin-mediated uPAR-release in vitro suggests that IL-6 has anti-inflammatory effects on endotoxin-mediated inflammation.

Adult↗

2B4 expression on natural killer cells increases in HIV-1 infected patients followed prospectively during highly active antiretroviral therapy.

Human immunodeficiency virus (HIV)-1 infection influences natural killer (NK) cell expression of inhibitory NK receptors and activating natural cytotoxicity receptors. It is unknown whether expression of the co-stimulatory NK cell receptor 2B4 (CD244) on NK cells and CD3+ CD8+ cells are affected by highly active antiretroviral therapy (HAART), low-level viraemia, proviral-DNA or immune activation in HIV-1 infected patients. A total of 101 HAART-treated HIV-1 infected patients with < or = 200 HIV-RNA copies/ml were followed prospectively for 24 months. HIV-RNA was investigated 3-monthly and 2B4 expression on CD3- CD16+ NK cells and CD3+ CD8+ cells, proviral-DNA and plasma soluble tumour necrosis factor receptor (sTNFr)-II were investigated 6-monthly. For comparison, 2B4 expression was investigated in 20 healthy individuals. The concentration of 2B4+ NK cells was initially reduced in HIV-1 infected patients (P < 0.001) but increased to a normal level during the 24 months' follow-up. The concentration of CD3+ CD8+ 2B4+ cells in HIV-1 infected patients was normal and did not change during follow-up. The relative fluorescence intensity (RFI) of 2B4 increased on both NK cells and CD3+ CD8+ cells during follow-up (both P < 0.001). Higher levels of proviral-DNA carrying cells and plasma sTNFrII were associated with reductions in the concentration of 2B4+ NK cells (all P < 0.05). HIV-RNA had no effect on 2B4 expression on NK cells or CD3+ CD8+ cells. These findings demonstrate that the concentration of 2B4+ NK cells normalizes during long-term HAART in HIV-1 infected patients. The finding that proviral-DNA and sTNFrII were associated negatively with the concentration of 2B4+ NK cells suggests that immune activation in HIV-1 infected patients receiving HAART influences the target cell recognition by NK cells.

Adult↗

Reduced release of intact and cleaved urokinase receptor in stimulated whole-blood cultures from human immunodeficiency virus-1-infected patients.

The blood levels of the soluble forms of the urokinase receptor (suPAR) are increased in human immunodeficiency virus (HIV)-1-infected patients. This study investigated whether the release of urokinase-type plasminogen activator receptor (uPAR) in whole-blood cultures was affected by HIV infection. The release of different uPAR forms in whole-blood cultures incubated 24 h with or without phytohemagglutinin and lipopolysaccharide was analysed in 47 HIV patients and 19 controls. suPAR was measured by enzyme-linked immunosorbent assay (ELISA) (bulk-suPAR) and three different time-resolved fluorescence immunoassays measuring three-domain suPAR [suPAR(I-III)], three- and two-domain suPAR [suPAR(I-III) + suPAR(II-III)] and one-domain suPAR [suPAR(I)]. The uPAR release was correlated to leucocyte subpopulations and plasma levels of suPAR. The stimulated net whole-blood culture release of bulk-uPAR, uPAR(I-III), uPAR(II-III) and uPAR(I) was reduced in HIV patients (all P < 0.01), whereas the spontaneous bulk-uPAR and uPAR(I-III) release was increased in HIV patients (both P < 0.05). The stimulated uPAR release in whole-blood cultures correlated well to leucocytes and circulating suPAR levels in controls, whereas the correlation was weaker to leucocytes and nonexisting to circulating suPAR levels in HIV patients. These findings demonstrate that HIV infection affects stimulated and spontaneous uPAR release in whole-blood cultures. Given that high blood levels of suPAR in HIV patients are linked to immune activation, the perturbations in uPAR release in whole-blood cultures from HIV patients may also reflect immune activation.

Adult↗

Malaria, intestinal parasites, and schistosomiasis among Barawan Somali refugees resettling to the United States: a strategy to reduce morbidity and decrease the risk of imported infections.

In 1997, enhanced health assessments were performed for 390 (10%) of approximately 4,000 Barawan refugees resettling to the United States. Of the refugees who received enhanced assessments, 26 (7%) had malaria parasitemia and 128 (38%) had intestinal parasites, while only 2 (2%) had Schistosoma haematobium eggs in the urine. Mass therapy for malaria (a single oral dose of 25 mg/kg of sulfadoxine-pyrimethamine) was given to all Barawan refugees 1-2 days before resettlement. Refugees >2 years of age and nonpregnant women received a single oral dose of 600 mg albendazole for intestinal parasite therapy. If mass therapy had not been provided, upon arrival in the United States an estimated 280 (7%) refugees would have had malaria infections and 1,500 (38%) would have had intestinal parasites. We conclude that enhanced health assessments provided rapid on-site assessment of parasite prevalence and helped decrease morbidity among Barawan refugees, as well as, the risk of imported infections.

Adolescent↗

US policy for disease control among imported nonhuman primates.

In 1990, in response to the occurrence of Ebola virus (subsequently identified as subtype Reston) infection among cynomolgus monkeys imported from the Philippines, the United States implemented strict disease control measures for handling nonhuman primates during transit and quarantine and initiated importer facility compliance inspections. Disease control measures emphasized protection of workers from exposure, use of containment facilities and procedures, measures to prevent spread of infection among animals, and laboratory testing of animals that die or become ill during quarantine. From 1991-1995, no outbreaks of filovirus infection occurred, and only one other disease outbreak (caused by Mycobacterium species) was recognized. In April 1996, Ebola virus (subtype Reston) infection was identified in another group of cynomolgus monkeys imported from the Philippines. The disease control measures implemented since the first Ebola virus (subtype Reston) outbreak appeared to work well. Currently, the 27 registered importer facilities import approximately 8500 nonhuman primates annually, and mortality rates are <1.0%. Importer facilities receive regular inspections, and compliance with disease control measures and disease reporting is excellent.

Animals↗

Agency for Toxic Substances and Disease Registry's 1997 priority list of hazardous substances. Latent effects--carcinogenesis, neurotoxicology, and developmental deficits in humans and animals.

In support of Superfund re-authorization legislation, the Division of Toxicology of the Agency for Toxic Substances and Disease Registry (ATSDR) prepared a chemical-specific consultation document for Congress that identified those chemicals with carcinogenic, neurological, or developmental adverse effects having a latency period longer than 6 years. The review was limited to the top 50 substances listed on ATSDR's 1997 Priority List of Hazardous Substances (Priority List). Among the top 50 chemicals, a review of the technical literature indicated that 38 (76%) were classified as "reasonably anticipated," "possibly," or "probably" capable of causing cancer in humans, based either on human and animal data. Eight chemicals (16%) had well-established cancer latency periods in humans of 6 years or more following exposure. Three substances (6%)--arsenic, creosote, and benzidine--had data indicating latency periods longer than 6 years. The technical literature review likewise confirmed the potential for neurological and developmental effects with a latency of 6 years. Twenty-seven (54%) of the top 50 substances caused acute and/or chronic neurotoxic effects; a number of these also caused neurological effects that persisted beyond 6 years (or the equivalent in animal studies) such as: behavioral problems, neurological deficiencies, reduced psychomotor development, cognitive deficiencies, and reduced IQ. Twenty-eight substances (56%) caused adverse developmental effects in offspring of exposed individuals or animals including increased fetal and infant mortality, decreased birth weights and litter sizes, and growth delays. Latency periods for related chemicals are expected to be similar due to structural and toxicological similarities.

Animals↗

Procedures utilized for primate import quarantine at the International Center for Gibbon Studies.

The intent of the Foreign Quarantine requirements (42 CFR 71.53) for nonhuman primates (NHPs) is to prevent the importation of potentially serious infectious diseases that are not endemic to the United States. In 1990, prompted by an outbreak of Ebola (Reston) hemorrhagic fever at an (NHP) quarantine facility, the Centers for Disease Control and Prevention (CDC) initiated unannounced inspections of all NHP importers' quarantine facilities. During the inspections, the majority did not meet the required infection control and containment standards. Numerous discrepancies were identified in infection control and NHP quarantine protocols. Zoos should have knowledge of CDC requirements and recommendations for the importation of NHPs into the United States. Zoos planning to import NHPs should register with the CDC and have their NHP quarantine facility and protocols inspected and approved by CDC's Division of Quarantine. Specific areas addressed must include protocols for in-transit shipping and handling, transport to the quarantine facility, biocontainment procedures (transfer of NHPs from shipping containers to quarantine cages, entering/exiting the quarantine room, routine daily and emergency procedures, protective clothing, infection control, infectious waste disposal), occupational health, and employee training. Here, we provide information on the approved protocols used for import quarantine at a single registered importer facility specializing in importation of gibbons (Hylobatidae) for species conservation purposes. These procedures are site specific and are not intended to be applicable to the needs of all NHP import facilities.

Animals↗

Blood lead values in dogs from a rural area (Champaign, IL in 1987).

We studied 87 healthy dogs to determine background levels of blood lead in dogs living in a presumably uncontaminated environment. We took blood samples from dogs and asked their owners for information regarding behavioral risk factors related to environmental lead exposure. The mean blood lead concentration was 5 (+/- 4.4) micrograms/dl (range 0-22 micrograms/dl).

Animals↗

Blood lead and zinc protoporphyrin levels in donkeys and mules near a secondary lead smelter in Jamaica, 1987-88.

During the course of an investigation into community lead poisoning near a secondary lead smelter in Jamaica, blood lead and zinc protoporphyrin levels were measured in 8 exposed and 6 (3 Jamaican, 3 US) unexposed donkeys and mules. The blood lead levels of 6 animals in the contaminated area ranged from 7.5 to 33 micrograms/dl (mean = 17.6 micrograms/dl), compared to 1.8 and 2.4 in unexposed Jamaican animals. More striking was the difference in zinc protoporphyrin levels; all 8 exposed donkeys and mules had values between 900 and 1890 micrograms/dl, compared with a range of 34-46 micrograms/dl for 3 Jamaican control donkeys. These findings suggest that zinc protoporphyrin may be a useful method of screening for subclinical lead toxicity in equines.

Animals↗

Compensatory weight gain in steers recovered from oak bud toxicosis.

Cattle that had recovered from clinical oak bud toxicosis (as assessed by normal BUN and serum creatinine values and good appetite) performed better than did clinically normal herdmates when weight gain and feed efficiency were compared. Both groups had a rate of weight gain (oak bud-exposed cattle, 1.76 kg/steer/d; control cattle, 1.57 kg/steer/d) that exceeded the feedlot mean value (approximately 1.4 kg/d) for cattle (of similar starting weight and diet) that had zeranol implants, and the difference was significant (P less than 0.005) for both groups. The difference in weight gain performance of oak bud-exposed cattle, compared with control cattle, was not highly significant; however, the improved feed efficiency was significantly (P less than 0.05) better than that in controls (2.57 kg of feed/kg of weight gain vs 3 kg of feed/kg of weight gain). On the basis of accepted criteria (increased rate of weight gain and efficiency of feed conversion), the group of oak bud-exposed cattle of this study had compensatory weight gain. Thus, cattle with good evidence of clinical recovery from oak bud toxicosis can be expected to perform in the feedlot at least as well as cattle not exposed to oak bud toxicosis, and may have compensatory weight gain.

Animal Feed↗

Oak toxicosis in cattle in northern California: clinical and pathologic findings.

Sixteen calves (3 to 8 months old) affected with oak toxicosis were studied. Clinical, laboratory, and pathologic findings during the peracute through chronic stages were documented. Of the calves studied, 1 died, and 9 others were euthanatized because death was imminent. To evaluate chronic effects, the 6 remaining cattle were euthanatized after 2 months. One calf with acute toxicosis was treated successfully with diuretics and fluid volume replacements containing sodium chloride and calcium. Clinical and laboratory data were compared between survivors and nonsurvivors. A statistically significant (P less than 0.02) difference was found only in serum creatinine concentration at the time of initial reexamination. A decrease in BUN and creatinine values during the next 7 days and the lack of anorexia after the acute phase were the best prognostic indicators for survival.

Animals↗

B-virus from pet macaque monkeys: an emerging threat in the United States?

Of primary concern when evaluating macaque bites are bacterial and B-virus infections. B-virus infection is highly prevalent (80% to 90%) in adult macaques and may cause a potentially fatal meningoencephalitis in humans. We examined seven nonoccupational exposure incidents involving 24 persons and eight macaques. Six macaques were tested for herpes B; four (67%) were seropositive. A common observation was that children were more than three times as likely to be bitten than adults. The virus must be assumed to be a potential health hazard in macaque bite wounds; this risk makes macaques unsuitable as pets.

Animals↗

Evidence of an unusual pattern of polychlorinated biphenyls in the serum of some residents and canines in Paoli, Pennsylvania.

The present study uses gas liquid chromatography (GLC) electron capture detection with packed and capillary columns to detect polychlorinated biphenyls (PCBs) in serum samples from people living near the electric car repair and maintenance facility of the Southeastern Pennsylvania Transit Authority in Paoli, Pennsylvania. Most of the cohort surveyed had serum patterns similar to patterns for Aroclor 1260 (AR 1260); a small portion (3/89) had patterns indicative of an AR with higher chlorination (e.g., AR 1268). In addition to analyzing serum samples from humans, we also analyzed serum samples from canines (pets of some of the subjects). In general, the serum pattern for canines was less descriptive for AR 1260 than the pattern for humans; however, the pattern for several canines (9/16) was that of the higher chlorinated PCBs (e.g., AR 1268). By using mass spectrometry and capillary column GLC, we confirmed the presence of high molecular weight polychlorinated congeners in both human and animal samples. We were not able to show a statistically significant relationship between serum patterns of PCBs in canines and their owners or between canines and certain behavioral traits (e.g., runs free, retrieves, hours outside, hours inside). However, the correlation between PCBs quantified as AR 1268 and canines' residence time was statistically significant.

Animals↗