Effects of clenbuterol on horses

Clenbuterol was intended as a treatment for respiratory diseases in horses, but has been used in multiple species, including humans, for its repartitioning of fat to lean effects (free fatty acids are released from adipose tissue to be used by tissues of higher priority). In the horse industry clenbuterol application is restricted to the treatment of chronic obstructive pulmonary disease and reactive airway disease (heaves). Negative effects of clenbuterol exposure include a decrease in maximum oxygen intake and increased muscle fatigue upon exercise. As a result of these and other negative effects, clenbuterol remains strictly controlled by the US Food and Drug Administration.

Synergism between the hbx gene and aflatoxin B-1 in the development of murine liver-cancer

Infection by hepatitis B virus (HBV) and exposure to dietary aflatoxin B-1 (AFB(1)) have both been implicated by epidemiological studies to be important risk factors in the development of hepatocellular carcinoma (HCC). Our ability to derive transgenic mice which develop liver cancer as a consequence of the expression of a single gene from HBV, the HBx gene, provides an opportunity to use this animal model to test whether AFB(1) can induce p53 mutations, particularly at codon 249, which are frequently detected in HCC and, as a result, act synergistically with HBV to accelerate the manifestation of disease. While AFB(1) significantly shortened the latency of tumor development in the HBx transgenic mice, the tumors did not have p53 mutations. As in tumors from the untreated transgenic mice, the p53 tumor suppressor protein is found bound to the HBx protein and sequestered in the cytoplasmic compartment of the tumor cell. Despite the frequent involvement of ras mutations in mouse tumors, we also have not detected activation of the ms p21 protein in the tumors from the AFB(1)-treated mice. We conclude that although AFB(1) can act as a co-factor with HBx to induce HCC in mice, its mode of action in vivo remains obscure.

Effects on condom use of an HIV prevention programme 36 months postintervention: a cluster randomized controlled trial among Bahamian youth

Data are lacking on long-term effects of HIV behavioural intervention programmes. In this study, we report intervention effects 36 months postintervention on condom use and relevant outcome variables from the theory-based programme 'Focus on Youth in the Caribbean' (FOYC). Participants (1360 sixth-grade youth) were randomized by school into: (1) FOYC, plus one of two brief parent interventions or (2) the control condition 'Wondrous Wetlands', plus a brief parent intervention. Mixed effect analysis demonstrated significant programme effects, including enhanced HIV/AIDS knowledge (effect size D = 0.44, 95% confidence interval [CI]: 0.43, 0.46), increased self-efficacy of (D = 0.42, 95% CI: 0.30, 0.54), skills for (D = 0.62, 95% CI: 0.56, 0.64) and intention to use a condom (D = 0.20, 95% CI: 0.03, 0.37). Youth who received FOYC plus the parental monitoring intervention had higher condom use rates (odds ratio = 1.49, 95% CI: 0.97, 2.28). Feedback effects from key variables were also detected, supporting the sustained effect.

Exciton Lifetimes in GaN

We have performed time resolved photoluminescence measurements of the exciton recombination in different GaN samples at low temperatures. In epitaxial layers the decay time of the free exciton is typically faster than 100 ps. This is due to a dominating non-radiative recombination process. In thick bulk samples we have resolved and measured the decay time of the free exciton with a value of about 200 ps. We believe that this value is close to the radiative lifetime for free excitons in GaN. We have also shown that excitation transfer occurs between free and bound exciton states. We have furthermore measured the decay of the donor and acceptor bound excitons, and obtained values of the decay time of 250 ps and 1200 ps, respectively.

Voyager 2 in the uranian system: imaging science results

Voyager 2 images of the southern hemisphere of Uranus indicate that submicrometersize haze particles and particles of a methane condensation cloud produce faint patterns in the atmosphere. The alignment of the cloud bands is similar to that of bands on Jupiter and Saturn, but the zonal winds are nearly opposite. At mid-latitudes (-70 degrees to -27 degrees ), where winds were measured, the atmosphere rotates faster than the magnetic field; however, the rotation rate of the atmosphere decreases toward the equator, so that the two probably corotate at about -20 degrees . Voyager images confirm the extremely low albedo of the ring particles. High phase angle images reveal on the order of 10(2) new ringlike features of very low optical depth and relatively high dust abundance interspersed within the main rings, as well as a broad, diffuse, low optical depth ring just inside the main rings system. Nine of the newly discovered small satellites (40 to 165 kilometers in diameter) orbit between the rings and Miranda; the tenth is within the ring system. Two of these small objects may gravitationally confine the e ring. Oberon and Umbriel have heavily cratered surfaces resembling the ancient cratered highlands of Earth's moon, although Umbriel is almost completely covered with uniform dark material, which perhaps indicates some ongoing process. Titania and Ariel show crater populations different from those on Oberon and Umbriel; these were probably generated by collisions with debris confined to their orbits. Titania and Ariel also show many extensional fault systems; Ariel shows strong evidence for the presence of extrusive material. About halfof Miranda's surface is relatively bland, old, cratered terrain. The remainder comprises three large regions of younger terrain, each rectangular to ovoid in plan, that display complex sets of parallel and intersecting scarps and ridges as well as numerous outcrops of bright and dark materials, perhaps suggesting some exotic composition.

Rearing environment affects development of the immune system in neonates

Early-life exposure to appropriate microbial flora drives expansion and development of an efficient immune system. Aberrant development results in increased likelihood of allergic disease or increased susceptibility to infection. Thus, factors affecting microbial colonization may also affect the direction of immune responses in later life. There is a need for a manipulable animal model of environmental influences on the development of microbiota and the immune system during early life. We assessed the effects of rearing under low- (farm, sow) and high-hygiene (isolator, milk formula) conditions on intestinal microbiota and immune development in neonatal piglets, because they can be removed from the mother in the first 24 h for rearing under controlled conditions and, due to placental structure, neither antibody nor antigen is transferred in utero. Microbiota in both groups was similar between 2 and 5 days. However, by 12-28 days, piglets reared on the mother had more diverse flora than siblings reared in isolators. Dendritic cells accumulated in the intestinal mucosa in both groups, but more rapidly in isolator piglets. Importantly, the minority of 2-5-day-old farm piglets whose microbiota resembled that of an older (12-28-day-old) pig also accumulated dendritic cells earlier than the other farm-reared piglets. Consistent with dendritic cell control of T cell function, the effects on T cells occurred at later time-points, and mucosal T cells from high-hygiene, isolator pigs made less interleukin (IL)-4 while systemic T cells made more IL-2. Neonatal piglets may be a valuable model for studies of the effects of interaction between microbiota and immune development on allergy.

Prospective Study of Vitamin D Levels in Sydney Patients with a New Diagnosis of Breast Cancer

Background: Vitamin D deficiency has been associated with malignancy in many reported studies. More recently an association has emerged between low levels of vitamin D and poorer outcome in breast cancer. Australian recommendations for vitamin D are defined as deficient if 25-OH vitamin D levels are ≤ 50nmol/L and severely deficient if ≤12.5nmol/L. We hypothesise that lower levels of vitamin D are associated with a more advanced disease at diagnosis.Methods: We conducted a prospective study in patients with a new diagnosis of breast cancer who presented to our area health service from January 1st 2008 to October 1st 2008. Patients were also included if their diagnosis occurred in the preceding 6 months and were referred onto the multidisciplinary breast care team for treatment in this time period. 25-OH vitamin D levels were measured for each patient during staging and details collected about each patients breast cancer characteristics. Patients completed a questionnaire assessing comorbidities, medications, diet and lifestyle effects which were likely to influence vitamin D levels. We used stage, disease requiring chemotherapy, and the need for mastectomy as surrogate endpoints for assessing disease extent.Results: 166 patients were recruited with a median age of 58 (range 21-100). The median vitamin D level was 48 (range of <10 to 170). 53% (n=88) patient were deficient (25-OH vitamin D ≤ 50nmol/L), 2% (n=3) patients were severely deficient (25-OH vitamin D ≤ 12.5nmol/L) and only 14% had sufficient levels (25-OH vitamin D >75nmol/L). The majority of patients reported the recommended sun exposure during weekdays (77%) and on weekends (86%). Most were had fair or medium skin tones (83%) and less than 10% wore sunscreen daily. Only 22% of patients had a potential identifiable cause for vitamin D deficiency. Vitamin D levels did not correlate directly with stage of disease (RR 1.03, 95% CI 0.86-1.23 p=0.85), however other surrogates for more advanced disease including the need for more aggressive treatment either with chemotherapy (RR 1.30, 95% CI 1.05-1.61 p=0.02) or mastectomy (RR 1.67 95% CI 1.03-2.7 p=0.04) were associated with low levels of vitamin D.Conclusions: Vitamin D deficiency is very prevalent in our population of patients diagnosed with breast cancer, despite perceived adequate sun exposure and lack of obvious cause. Lower levels of vitamin D did not directly correlate with more advanced stage of the disease at diagnosis; however patients with low levels of vitamin D were more likely to need chemotherapy or require mastectomy, which may suggest a more aggressive disease. The cause of breast cancer remains multifactorial and vitamin D deficiency is only one part of this complex disease.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6071.

Remediating dinoseb-contaminated soil with zerovalent iron

Dinoseb, a dinitroherbicide, was once commonly used in aerial crop dusting of agronomic crops in the western United States. Widespread use combined with improper disposal practices at rural air strips has contaminated numerous sites. Our objective was to determine if zerovalent iron (Fe(0)) could remediate dinoseb-contaminated soil. This was accomplished by conducting a series of batch experiments where we first determined if Fe(0) could remove dinoseb in aqueous solutions, then in contaminated soil slurries, and finally, in unsaturated soil microcosms (25 degrees C, theta(g)=0.30 kg H(2)O kg(-1)). Results showed quantitative dinoseb removal in the presence of Fe(0) in all three media (aqueous solutions, soil slurries, moist soils) and that removal increased by including either ferrous or aluminum sulfate with the iron treatment. Incubating contaminated soils with Fe(0) or Fe(0) plus salts (FeSO(4) or Al(2)(SO(4))(3)) resulted in 100% removal of dinoseb within 7 d. Liquid chromatography/mass spectrometry (LC/MS) analysis of degradation products showed the transformations imposed by the iron treatments were reduction of one or both nitro groups to amino groups. These amino degradation products were further transformed to quinonimine and benzoquinone and did not persist. These results support the use of zerovalent iron for on-site treatment of dinoseb-contaminated soil.

Field-scale cleanup of atrazine and cyanazine contaminated soil with a combined chemical-biological approach

A former agrichemical dealership in western Nebraska was suspected of having contaminated soil. Our objective was to characterize and remediate the contaminated site by a combined chemical-biological approach. This was accomplished by creating contour maps of the on-site contamination, placing the top 60 cm of contaminated soil in windrows and mixing with a mechanical high-speed mixer. Homogenized soil containing both atrazine [6-chloro-N-ethyl-N'-isopropyl-1,3,5-triazine-2,4-diamine] and cyanazine {2-[[4-chloro-6-(ethylamino)-1,3,5-triazin-2-yl] amino]-2-methylpropanenitrile} was then used in laboratory investigations to determine optimum treatments for pesticide destruction. Iron suspension experiments verified that zerovalent iron (Fe(0)) plus ferrous sulfate (FeSO(4).7H(2)O) removed more than 90% of both atrazine and cyanazine within 14 d. Liquid chromatography/mass spectrometry (LC/MS) analysis of the atrazine solution after treating with Fe(0) and ferrous sulfate identified several degradation products commonly associated with biodegradation (i.e., deethlyatrazine (DEA), deisopropylatrazine (DIA), hydroxyatrazine (HA), and ammelines). Biological treatment evaluated emulsified soybean [Glycine max (L.) Merr.] oil (EOS) as a carbon source to stimulate biodegradation in static soil microcosms. Combining emulsified soybean oil with the chemical amendments resulted in higher destruction efficiencies (80-85%) and reduced the percentage of FeSO(4) needed. This chemical-biological treatment (Fe(0) + FeSO(4) + EOS, EOS Remediation, Raleigh, NC) was then applied with water to 275 m(3) of contaminated soil in the field. Windrows were tightly covered with clear plastic to increase soil temperature and maintain soil water content. Temporal sampling (0-342 d) revealed atrazine and cyanazine concentrations decreased by 79 to 91%. These results provide evidence that a combined chemical-biological approach can be used for on-site, field-scale treatment of pesticide-contaminated soil.

Condom-use skills checklist: a proxy for assessing condom-use knowledge and skills when direct observation is not possible

Because of the continued importance of correct condom-use in controlling the HIV epidemic and the limited availability of tools for assessing correct condom-use, methods for assessing condom-application skills, especially when direct observation is not feasible, are needed. Accordingly, in the context of a high-risk population (The Bahamas) for HIV, a 17-item scale--the Condom-use Skills Checklist (CUSC)--was developed for use among young adolescents and adults. The rationale and approach to developing the scale and some measures of internal consistency, construct validity, and criterion-related validity have been described. It is concluded that the scale offers a reasonable alternative to direct observation among older subjects and that further development may make it more useful among pre-adolescents.

A UK consensus on the management of the bladder in multiple sclerosis

Bladder symptoms in multiple sclerosis (MS) are common and distressing but also highly amenable to treatment. A meeting of stakeholders involved in patients' continence care, including neurologists, urologists, primary care, MS nurses and nursing groups was recently convened to formulate a UK consensus for management. National Institute for Health and Clinical Excellence (NICE) criteria were used for producing recommendations based on a review of the literature and expert opinion. It was agreed that in the majority of cases, successful management could be based on a simple algorithm which includes using reagent sticks to test for urine infection and measurement of the post micturition residual urine volume. This is in contrast with published guidelines from other countries which recommend cystometry. Throughout the course of their disease, patients should be offered appropriate management options for treatment of incontinence, the mainstay of which is antimuscarinic medications, in combination, if necessary, with clean intermittent self-catheterisation. The evidence for other measures, including physiotherapy, alternative strategies aimed at improving bladder emptying, other medications and detrusor injections of botulinum toxin A was reviewed. The management of urinary tract infections as well as the bladder problems as part of severe disability were discussed and recommendations agreed.