Targeting Unique Ligand Binding Domain Structural Features Downregulates DKK1 in Y537S ESR1 Mutant Breast Cancer Cells.

Resistance to endocrine therapies remains a major clinical hurdle in breast cancer. Mutations to estrogen receptor alpha (ERα) arise after continued therapeutic pressure. Next generation selective estrogen receptor modulators and degraders/downregulators (SERMs and SERDs) show clinical efficacy, but responses are often non-durable. A tyrosine to serine point mutation at position 537 in the ERα ligand binding domain (LBD) is among the most common and most pathogenic alteration in this setting. It enables endocrine therapy resistance by superceding intrinsic structural-energetic gatekeepers of ER hormone-dependence, it enhances metastatic burden by enabling neomorphic ER-dependent transcriptional programs, and it resists SERM and SERD inhibiton by reducing their binding affinities and abilities to antagonize transcriptional coregulator binding. However, a subset of SERMs and SERDs can achieve efficacy by adopting poses that force the mutation to engage in a new interaction that favors the therapeutic receptor antagonist conformation. We previously described a chemically unconventional SERM, T6I-29, that demonstrates significant anti-proliferative activities in Y537S ERα breast cancer cells. Here, we use a comprehensive suite of structural-biochemical, in vitro, and in vivo approaches to better T6I-29's activities in breast cancer cells harboring Y537S ERα. RNA sequencing in cells treated with T6I-29 reveals a neomorphic downregulation of DKK1, a secreted glycoprotein known to play oncogenic roles in other cancers. Importantly, we find that DKK1 is significantly enriched in ER+ breast cancer plasma compared to healthy controls. This study shows how new SERMs and SERDs can identify new therapeutic pathways in endocrine-resistant ER+ breast cancers.

Targeting Unique Ligand Binding Domain Structural Features Downregulates DKK1 in Y537S ESR1 Mutant Breast Cancer Cells.

Resistance to endocrine therapies remains a major clinical hurdle in breast cancer. Mutations to estrogen receptor alpha (ERα) arise after continued therapeutic pressure. Next generation selective estrogen receptor modulators and degraders/downregulators (SERMs and SERDs) show clinical efficacy, but responses are often non-durable. A tyrosine to serine point mutation at position 537 in the ERα ligand binding domain (LBD) is among the most common and most pathogenic alteration in this setting. It enables endocrine therapy resistance by superceding intrinsic structural-energetic gatekeepers of ER hormone-dependence, it enhances metastatic burden by enabling neomorphic ER-dependent transcriptional programs, and it resists SERM and SERD inhibiton by reducing their binding affinities and abilities to antagonize transcriptional coregulator binding. However, a subset of SERMs and SERDs can achieve efficacy by adopting poses that force the mutation to engage in a new interaction that favors the therapeutic receptor antagonist conformation. We previously described a chemically unconventional SERM, T6I-29, that demonstrates significant anti-proliferative activities in Y537S ERα breast cancer cells. Here, we use a comprehensive suite of structural-biochemical, in vitro, and in vivo approaches to better T6I-29's activities in breast cancer cells harboring Y537S ERα. RNA sequencing in cells treated with T6I-29 reveals a neomorphic downregulation of DKK1, a secreted glycoprotein known to play oncogenic roles in other cancers. Importantly, we find that DKK1 is significantly enriched in ER+ breast cancer plasma compared to healthy controls. This study shows how new SERMs and SERDs can identify new therapeutic pathways in endocrine-resistant ER+ breast cancers.

Cardiovascular disease and diabetes in HIV-positive and HIV-negative gay and bisexual men over the age of 55 years in Australia: insights from the Australian Positive & Peers Longevity Evaluation Study.

OBJECTIVES: As HIV-positive people age, diagnosis and management of comorbidities associated with ageing are of increasing concern. In this study, we aimed to compare the self-reported prevalences of heart disease, stroke, thrombosis and diabetes in older Australian HIV-positive and HIV-negative gay and bisexual men (GBM). METHODS: We analysed data from the Australian Positive & Peers Longevity Evaluation Study (APPLES), a study of a prospectively recruited cross-sectional sample of 228 (51.1%) HIV-positive and 218 (48.9%) HIV-negative GBM, aged ≥ 55 years. Regression methods were used to assess the association of HIV status with self-reported comorbidities. RESULTS: Of 446 patients, 389 [200 (51.4%) HIV-positive] reported their disease history. The reported prevalence of comorbidities was higher in the HIV-positive group than in the HIV-negative group: heart disease, 19.5 versus 12.2%; stroke, 7.5 versus 4.2%; thrombosis, 10.5 versus 4.2%; and diabetes, 15.0 versus 9.0%, respectively. In adjusted analyses, HIV-positive GBM had significantly increased odds of reporting heart disease [adjusted odds ratio (aOR) 1.99; P = 0.03] and thrombosis (aOR 2.87; P = 0.01). In our analysis, HIV status was not significantly associated with either age at diagnosis of heart disease (median 53 years for HIV-positive GBM versus 55 years for HIV-negative GBM; P = 0.64) or 5-year cardiovascular disease (CVD) risk estimated using the Framingham risk score. CONCLUSIONS: HIV-positive GBM more commonly reported heart disease and thrombosis compared with their HIV-negative peers. These results further highlight the need to understand the impact of HIV on age-related comorbidities in GBM, to guide optimal screening and treatment strategies to reduce the risk of these comorbidities among the HIV-positive population.

A longitudinal cohort study of HIV 'treatment as prevention' in gay, bisexual and other men who have sex with men: the Treatment with Antiretrovirals and their Impact on Positive And Negative men (TAIPAN) study protocol.

BACKGROUND: Australia has increased coverage of antiretroviral treatment (ART) over the past decade, reaching 73% uptake in 2014. While ART reduces AIDS-related deaths, accumulating evidence suggests that it could also bolster prevention efforts by reducing the risk of HIV transmission ('treatment as prevention'). While promising, evidence of community-level impact of treatment as prevention on reducing HIV incidence among gay and bisexual men is limited. We describe a study protocol that aims to determine if scale up of testing and treatment for HIV leads to a reduction in community viraemia and, in turn, if this reduction is temporally associated with a reduction in HIV incidence among gay and bisexual men in Australia's two most populous states. METHODS: Over the period 2009 to 2017, we will establish two cohorts making use of clinical and laboratory data electronically extracted retrospectively and prospectively from 73 health services and laboratories in the states of New South Wales and Victoria. The 'positive cohort' will consist of approximately 13,000 gay and bisexual men (>90% of all people living with HIV). The 'negative cohort' will consist of at least 40,000 HIV-negative gay and bisexual men (approximately half of the total population). Within the negative cohort we will use standard repeat-testing methods to calculate annual HIV incidence. Community prevalence of viraemia will be defined as the proportion of men with a viral load ≥200RNA copies/mm3, which will combine viral load data from the positive cohort and viraemia estimates among those with an undiagnosed HIV infection. Using regression analyses and adjusting for behavioural and demographic factors associated with infection, we will assess the temporal association between the community prevalence of viraemia and the incidence of HIV infection. Further analyses will make use of these cohorts to assess incidence and predictors of treatment initiation, repeat HIV testing, and viral suppression. DISCUSSION: This study will provide important information on whether 'treatment as prevention' is associated with a reduction in HIV incidence at a community level among gay and bisexual men.

Pharmacokinetic and Pharmacodynamic Comparison of Once-Daily Efavirenz (400 mg vs. 600 mg) in Treatment-Naïve HIV-Infected Patients: Results of the ENCORE1 Study.

Daily efavirenz 400 mg (EFV400) was virologically noninferior to 600 mg (EFV600) at 48 weeks in treatment-naïve patients. We evaluated EFV400 and EFV600 pharmacokinetics (NONMEM v. 7.2), assessing patient demographics and genetic polymorphisms (CYP2B6, CYP2A6, CYP3A4, NR1I3) as covariates and explored relationships with efficacy (plasma HIV-RNA (pVL) <200 copies/mL) and safety outcomes at 48 weeks in 606 randomized ENCORE1 patients (female = 32%, African = 37%, Asian = 33%; EFV400 = 311, EFV600 = 295). CYP2B6 516G>T/983T>C/CYP2A6*9B/*17 and weight were associated with efavirenz CL/F. Exposure was significantly lower for EFV400 (geometric mean ratio, GMR; 90% confidence interval, CI: 0.73 (0.68-0.78)) but 97% (EFV400) and 98% (EFV600) of evaluable pVL was <200 copies/mL at 48 weeks (P = 0.802). Four of 20 patients with mid-dose concentrations <1.0 mg/L had pVL ≥200 copies/mL (EFV400 = 1; EFV600 = 3). Efavirenz exposure was similar between those with and without efavirenz-related side effects (GMR; 90% CI: 0.95 (0.88-1.02)). HIV suppression was comparable between doses despite significantly lower EFV400 exposure. Comprehensive evaluation of efavirenz pharmacokinetics/pharmacodynamics revealed important limitations in the accepted threshold concentration.

Ritonavir-boosted lopinavir plus nucleoside or nucleotide reverse transcriptase inhibitors versus ritonavir-boosted lopinavir plus raltegravir for treatment of HIV-1 infection in adults with virological failure of a standard first-line ART regimen (SECOND-LINE): a randomised, open-label, non-inferiority study.

BACKGROUND: Uncertainty exists about the best treatment for people with HIV-1 who have virological failure with first-line combination antiretroviral therapy of a non-nucleoside analogue (NNRTI) plus two nucleoside or nucleotide analogue reverse transcriptase inhibitors (NtRTI). We compared a second-line regimen combining two new classes of drug with a WHO-recommended regimen. METHODS: We did this 96-week, phase 3b/4, randomised, open-label non-inferiority trial at 37 sites worldwide. Adults with HIV-1 who had confirmed virological failure (plasma viral load >500 copies per mL) after 24 weeks or more of first-line treatment were randomly assigned (1:1) to receive ritonavir-boosted lopinavir plus two or three NtRTIs (control group) or ritonavir-boosted lopinavir plus raltegravir (raltegravir group). The randomisation sequence was computer generated with block randomisation (block size four). Neither participants nor investigators were masked to allocation. The primary endpoint was the proportion of participants with plasma viral load less than 200 copies per mL at 48 weeks in the modified intention-to-treat population, with a non-inferiority margin of 12%. This study is registered with ClinicalTrials.gov, number NCT00931463. FINDINGS: We enrolled 558 patients, of whom 541 (271 in the control group, 270 in the raltegravir group) were included in the primary analysis. At 48 weeks, 219 (81%) patients in the control group compared with 223 (83%) in the raltegravir group met the primary endpoint (difference 1·8%, 95% CI -4·7 to 8·3), fulfilling the criterion for non-inferiority. 993 adverse events occurred in 271 participants in the control group versus 895 in 270 participants in the raltegravir group, the most common being gastrointestinal. INTERPRETATION: The raltegravir regimen was no less efficacious than the standard of care and was safe and well tolerated. This simple NtRTI-free treatment strategy might extend the successful public health approach to management of HIV by providing simple, easy to administer, effective, safe, and tolerable second-line combination antiretroviral therapy. FUNDING: University of New South Wales, Merck, AbbVie, the Foundation for AIDS Research.

Raltegravir resistance in the cerebrospinal fluid.

We report the first published case of integrase inhibitor resistance in the central nervous system compartment in the absence of evidence of integrase inhibitor resistance in the plasma of a patient without human immunodeficiency virus (HIV)-encephalitis in the context of other HIV-associated central nervous system infections.

The 2010 Royal Australasian College of Physicians' policy statement 'Circumcision of infant males' is not evidence based.

Infant male circumcision (MC) is an important issue guided by Royal Australasian College of Physicians (RACP) policy. Here we analytically review the RACP's 2010 policy statement 'Circumcision of infant males'. Comprehensive evaluation in the context of published research was used. We find that the Statement is not a fair and balanced representation of the literature on MC. It ignores, downplays, obfuscates or misrepresents the considerable evidence attesting to the strong protection MC affords against childhood urinary tract infections, sexually transmitted infections (human immunodeficiency virus, human papilloma virus, herpes simplex virus type 2, trichomonas and genital ulcer disease), thrush, inferior penile hygiene, phimosis, balanoposthitis and penile cancer, and in women protection against human papilloma virus, herpes simplex virus type 2, bacterial vaginosis and cervical cancer. The Statement exaggerates the complication rate. Assertions that 'the foreskin has a functional role' and 'is a primary sensory part of the penis' are not supported by research, including randomised controlled trials. Instead of citing these and meta-analyses, the Statement selectively cites poor quality studies. Its claim, without support from a literature-based risk-benefit analysis, that the currently available evidence does 'not warrant routine infant circumcision in Australia and New Zealand' is misleading. The Statement fails to explain that performing MC in the neonatal period using local anaesthesia maximises benefits, safety, convenience and cost savings. Because the RACP's policy statement is not a fair and balanced representation of the current literature, it should not be used to guide policy. In the interests of public health and individual well-being, an extensive, comprehensive, balanced review of the scientific literature and a risk-benefit analysis should be conducted to formulate policy.

Assessing adherence in Thai patients taking combination antiretroviral therapy.

In settings where medications and viral load (VL) monitoring are limited by cost, clinicians need reliable ways to assess patient adherence to therapy. We assessed sensitivity and specificity of two self-reported adherence tools (a visual analogue scale [VAS] and the CASE [Center for Adherence Support Evaluation] adherence index), against a standard of detectable VL, with 288 patients from three sites in Thailand. We also assessed predictors of non-adherence. The sensitivity and specificity of the VAS <95% and CASE adherence index ≤11 against a VL >50 copies/mL were 26% and 90%, 19% and 95%, respectively. Against a VL ≥1000 copies/mL sensitivities increased to 55% and 36%, respectively, and specificities were unchanged. Attending a clinic not staffed by HIV specialists (odds ratio [OR] 3.14; 95% confidence interval [CI] 1.19-8.34) and being educated to primary school level or less (OR 2.24; 95% CI 1.01-4.94) were associated with self-reported adherence <95% on the VAS in multivariate analysis. Adherence assessed by the VAS was a more accurate predictor of detectable VL. Policy-makers in resource-limited settings should ensure that treatment centres are staffed with well-trained personnel aware of the importance of good patient adherence.

Dynamics of cognitive change in HIV-infected individuals commencing three different initial antiretroviral regimens: a randomized, controlled study.

BACKGROUND: Improvements in neurocognitive (NC) function have been associated with commencing antiretroviral therapy in HIV-infected subjects. However, the dynamics of such improvements are poorly understood. METHODS: We assessed changes in NC function via a validated computerized battery (CogState™, Melbourne, Victoria, Australia) at baseline and after 24 and 48 weeks in a subset of therapy-naïve neuro-asymptomatic HIV-infected subjects, randomized to commence three different antiretroviral regimens. RESULTS: Of 28 subjects enrolled in the study, nine, eight and 11 were randomly allocated to commence tenofovir/emtricitabine with efavirenz (arm 1), atazanavir/ritonavir (arm 2) and zidovudine/abacavir (arm 3), respectively. Overall improvements in NC function were observed at week 24 and function continued to improve at week 48 (changes in z-score for overall cognitive global score of 0.16 and 0.18 at weeks 24 and 48, respectively). Within the NC speed domains, generally greater improvements were observed in arms 2 and 3, compared with arm 1 (changes in z-score for composite speed scores at weeks 24/48 of 0.16/0.16, -0.29/-0.24 and -0.15/-0.31 in arms 1, 2 and 3, respectively; P = 0.04 for change at week 48 in arm 3 versus arm 1). Finally, improvements in executive function occurred later (only observed at week 48) and were driven by improvements in arm 3 (z-score changes of 0.23, 0.06 and -0.78 in arms 1, 2 and 3, respectively; P = 0.02 for change in arm 3 versus arm 1). CONCLUSION: Improvements in NC function continue over the first year after initiating antiretroviral therapy in neuro-asymptomatic HIV-infected subjects.

Hyperlactataemia in HIV-infected subjects initiating antiretroviral therapy in a large randomized study (a substudy of the INITIO trial).

OBJECTIVE: The aim of the study was to evaluate the predictive value of clinical and molecular risk factors, including peripheral blood mononuclear cell (PBMC) mitochondrial DNA (mtDNA) and mitochondrial RNA (mtRNA), for the development of lactic acidosis (LA) and symptomatic hyperlactataemia (SHL). METHODS: In a substudy of a large multicentre, randomized trial of three antiretroviral regimens, all containing didanosine (ddI) and stavudine (d4T), in antiretroviralnaïve, HIV-1-infected patients, patients with LA/SHL ('cases') were compared with those without LA/SHL in a univariate analysis, with significant parameters analysed in a multivariate model. In a molecular substudy, PBMC mtDNA and mtRNA from cases and matched controls at baseline and time of event were examined. RESULTS: In 911 subjects followed for a median of 192 weeks, 24 cases were identified (14 SHL and 10 LA). In univariate analysis, cases were more likely to be female (P=0.05) and to have a high body mass index (BMI) (P=0.02). In multivariate analyses, only BMI remained an independent predictor of the development of LA/SHL (P=0.03). Between cases and controls there was no significant difference in mtDNA copy number at baseline (389 vs. 411 copies/cell, respectively; P=0.60) or at time of event (329 vs. 474 copies/cell, respectively; P=0.21), in the change in mtDNA copy number from baseline to event (-65 vs. +113 copies/cell, respectively; P=0.12), in mtRNA expression at baseline or time of event, or in the change in mtRNA expression from baseline to event. CONCLUSION: The development of LA/SHL was associated with increased BMI, but PBMC mtDNA and mtRNA did not predict LA/SHL. This demonstrates the ineffectiveness of routine measurement of PBMC mtDNA in patients on ddI and d4T as a means of predicting development of LA/SHL.

Genital shedding of HIV after scheduled treatment interruption.

This study assessed genital shedding of HIV in patients on intermittent combination antiretroviral therapy (cART) and assessed predictors of having detectable genital HIV RNA in 156 Thai patients with CD4 > 350 cells/µL and HIV RNA ≤50 copies/mL who were randomized to continuous therapy (CT, n = 65) or CD4-guided cART (n = 91). There were 383 matched genital and plasma HIV RNA samples (CT: 158, CD4 guided: 225). In 14 samples collected within eight weeks of treatment interruption, detectable HIV RNA was present in 29% of genital samples and 71% of plasma samples. In 55 samples collected after eight weeks of treatment interruption, detectable HIV RNA was present in 60% of genital samples and 98% of plasma samples. In 110 samples collected up to 96 weeks after treatment re-initiation, detectable genital HIV RNA was found in 8% of samples and all of these were within the first 17 weeks. Independent predictors of detectable genital HIV RNA were increasing age and increasing concentrations of HIV RNA in plasma. These findings support the role of cART in maintaining undetectable HIV RNA in genital secretions.

Antiviral activity of apricitabine in treatment-experienced HIV-1-infected patients with M184V who are failing combination therapy.

OBJECTIVES: Apricitabine (ATC) is a novel deoxycytidine analogue nucleoside reverse transcriptase inhibitor (NRTI) with significant antiviral activity in vitro, including activity against HIV-1 with reverse transcriptase mutations that confer resistance to other NRTIs. ATC has shown promising antiviral activity and good tolerability when given as monotherapy for 10 days in treatment-naïve HIV-1-infected patients. METHODS: In this Phase II randomized, double-blind study, 51 treatment-experienced HIV-1-infected patients with the reverse transcriptase mutation M184V who were failing therapy which included lamivudine (3TC) were randomized to receive twice-daily 600 mg ATC, 800 mg ATC or 150 mg 3TC for 21 days. Patients remained on their existing background regimen until day 21, when background therapy could be optimized according to genotype at screening. RESULTS: At day 21, the mean change in viral load was -0.71 and -0.90 log(10) HIV-1 RNA copies/mL in the 600 and 800 mg ATC groups, respectively, compared with a -0.03 log(10) change in the 3TC group. In patients with at least three thymidine analogue mutations (TAMs) at baseline, greater reductions in viral load were observed in the 800 mg ATC group at day 21 than in the 600 mg ATC group. Few genotypic changes were detected at day 21 [two patients (600 mg ATC) lost and three patients (800 mg ATC) gained a TAM] and all patients with detectable virus retained the M184V mutation. The safety profiles of the two ATC doses were similar to that of 3TC. CONCLUSIONS: Over the 21-day treatment period, ATC showed promising antiviral activity and was well tolerated in treatment-experienced patients with M184V, with or without additional TAMs.

Predictors of bacterial pneumonia in Evaluation of Subcutaneous Interleukin-2 in a Randomized International Trial (ESPRIT).

BACKGROUND AND OBJECTIVES: Bacterial pneumonia still contributes to morbidity/mortality in HIV infection despite effective combination antiretroviral therapy (cART). Evaluation of Subcutaneous Interleukin-2 in a Randomized International Trial (ESPRIT), a trial of intermittent recombinant interleukin-2 (rIL-2) with cART vs. cART alone (control arm) in HIV-infected adults with CD4 counts ≥300cells/µL, offered the opportunity to explore associations between bacterial pneumonia and rIL-2, a cytokine that increases the risk of some bacterial infections. METHODS: Baseline and time-updated factors associated with first-episode pneumonia on study were analysed using multivariate proportional hazards regression models. Information on smoking/pneumococcal vaccination history was not collected. RESULTS: IL-2 cycling was most intense in years 1-2. Over ≈7 years, 93 IL-2 [rate 0.67/100 person-years (PY)] and 86 control (rate 0.63/100 PY) patients experienced a pneumonia event [hazard ratio (HR) 1.06; 95% confidence interval (CI) 0.79, 1.42; P=0.68]. Median CD4 counts prior to pneumonia were 570cells/µL (IL-2 arm) and 463cells/µL (control arm). Baseline risks for bacterial pneumonia included older age, injecting drug use, detectable HIV viral load (VL) and previous recurrent pneumonia; Asian ethnicity was associated with decreased risk. Higher proximal VL (HR for 1 log(10) higher VL 1.28; 95% CI 1.11, 1.47; P<0.001) was associated with increased risk; higher CD4 count prior to the event (HR per 100 cells/µL higher 0.94; 95% CI 0.89, 1.0; P=0.04) decreased risk. Compared with controls, the hazard for a pneumonia event was higher if rIL-2 was received <180 days previously (HR 1.66; 95% CI 1.07, 2.60; P=0.02) vs.≥180 days previously (HR 0.98; 95% CI 0.70, 1.37; P=0.9). Compared with the control group, pneumonia risk in the IL-2 arm decreased over time, with HRs of 1.41, 1.71, 1.16, 0.62 and 0.84 in years 1, 2, 3-4, 5-6 and 7, respectively. CONCLUSIONS: Bacterial pneumonia rates in cART-treated adults with moderate immunodeficiency are high. The mechanism of the association between bacterial pneumonia and recent IL-2 receipt and/or detectable HIV viraemia warrants further exploration.

The effects of enfuvirtide therapy on body composition and metabolic parameters over 48 weeks in the TORO body imaging substudy.

OBJECTIVE: The aim of the study was to compare the metabolic and morphological effects of enfuvirtide plus an optimized background (OB) regimen vs. OB alone (control group) in treatment-experienced patients in the T-20 vs. Optimized Regimen Only (TORO) studies. METHODS: Body composition and metabolic changes were investigated in patients over 48 weeks, based on fasting chemistries, body weight, and other anthropometric measurements. Dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT) scans were performed in a patient subgroup (n=155) at baseline and at weeks 24 and 48. RESULTS: At week 48, mean changes from baseline were similar between treatment groups for glucose, insulin, C-peptide, total cholesterol, low-density lipoprotein (LDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, high-density lipoprotein (HDL) cholesterol and triglyceride levels. The enfuvirtide group experienced a significant increase in body weight [mean change from baseline +0.99 kg; 95% confidence interval (CI) +0.54, +1.44] and, in those who had body scans, there was a significant increase in truncal fat (by DEXA: median change +419.4 g; 95% CI+71.3, +767.5) and total fat [visceral adipose tissue (VAT)+subcutaneous adipose tissue (SAT) by single-slice abdominal CT scan: median change +25.5 cm(2) ; 95% CI+8.9, +42.0] over 48 weeks; significant increases in these parameters were not seen in the control group. There was no significant change in truncal:peripheral fat ratio in either the enfuvirtide or the control group. CONCLUSION: The addition of enfuvirtide to an OB regimen does not appear to have unfavourable effects on fat distribution or metabolic parameters.

Temporal relationships of the LH surge and ovulation to echotexture and power Doppler signals of blood flow in the wall of the preovulatory follicle in heifers.

Changes in echotexture and blood flow in the wall of preovulatory follicles in heifers were studied in relation to the LH surge and ovulation in gonadotrophin-releasing hormone-induced (n = 7; Experiment 1) and spontaneous (n = 8; Experiment 2) ovulators. Ultrasonographic examinations and blood sampling were performed either every hour (Experiment 1) or every 6 h (Experiment 2). The interval from LH peak to ovulation in induced and spontaneous ovulators was 27.1 +/- 0.3 and 34.5 +/- 1.5 h, respectively. Follicle diameter did not increase between the LH peak and ovulation. In the induced ovulators, serration of the stratum granulosum was detected in one (14%), two (29%), three (43%) and four (57%) heifers at 4, 3, 2 and 1 h before ovulation, respectively. An initial increase in blood flow (P < 0.001) encompassed the LH peak in both experiments. In the induced ovulators, blood flow increased (P < 0.02) to maximum 3 h after the LH peak, maintained a plateau for 5 h, decreased (P < 0.05) between 9 and 14 h, increased (P < 0.05) again between 19 and 21 h and then decreased (P < 0.01) between 25 and 26 h (1 h before ovulation). The biphasic increase and decrease in blood flow and serration of the granulosum in the wall of the preovulatory follicle in cattle are novel findings.

No significant effect of uridine or pravastatin treatment for HIV lipoatrophy in men who have ceased thymidine analogue nucleoside reverse transcriptase inhibitor therapy: a randomized trial.

BACKGROUND: Lipoatrophy can complicate thymidine analogue nucleoside reverse transcriptase inhibitor (tNRTI)-based antiretroviral therapy (ART). Lipoatrophy may be less likely with ART including ritonavir-boosted lopinavir (LPV/r). Small, placebo-controlled studies found that uridine (in tNRTI recipients) and pravastatin improved HIV lipoatrophy over 12 weeks. Today, most patients with lipoatrophy receive non-tNRTI-based ART; the effect of uridine in such patients is unknown. METHODS: We performed a prospective, randomized trial in lipoatrophic adults with plasma HIV RNA<50 HIV-1 RNA copies/mL on tNRTI-sparing ART including LPV/r. Patients received uridine [36 g three times a day (tid) on 10 consecutive days per month; n=10], pravastatin [40 mg every night (nocte); n=12], uridine plus pravastatin (n=11) or neither (n=12) for 24 weeks. The primary endpoint was mean change in limb fat mass as assessed by dual-energy X-ray absorptiometry (DEXA). With 20 patients per intervention, the study had 80% power to detect a mean difference between a treatment and the control of 0.5 kg, assuming a standard deviation of 0.9 and an alpha threshold equal to 5% (two-sided). RESULTS: Of 45 participants (all men, with median age 49.5 years and median limb fat 2.6 kg), two discontinued pravastatin and one participant stopped both pravastatin and uridine. The difference between the mean changes in limb fat mass for uridine vs. no uridine was 0.03 kg [95% confidence interval (CI) -0.35, +0.28; P=0.79]. The respective difference for pravastatin was -0.03 kg (95% CI -0.29, +0.34; P=0.84). Pravastatin slightly decreased total cholesterol (0.44 mmol/L; P=0.099). Visceral adipose tissue measured by computed tomography did not change significantly. CONCLUSION: In this population and at the doses used, neither uridine nor pravastatin for 24 weeks significantly increased limb fat mass.

Presynchronization with gonadotropin-releasing hormone increases the proportion of Bos indicus-influenced females ovulating at initiation of synchronization but fails to improve synchronized new follicular wave emergence or fixed-time artificial insemination conception rates using intravaginal progesterone, gonadotropin-releasing hormone, and prostaglandin F2alpha1.

The objectives were to evaluate the effect of presynchronization with GnRH on pregnancy rates (Exp. 1) and ovarian events (Exp. 2) in Bos indicus-influenced females synchronized with CO-Synch + controlled internal drug release (CIDR) as described below. In Exp. 1, a total of 135 Brahman x Hereford (F(1)) females were assigned randomly after stratification to 1) Presynch; presynchronization followed by CO-Synch + CIDR, or 2) No Presynch; CO-Synch + CIDR without presynchronization. On d -7, cattle received 100 microg of GnRH or 2 mL of intramuscular (i.m.) saline. On d 0, all cattle received a CIDR and i.m. injection of GnRH (GnRH-1), followed by CIDR removal and i.m. injection of 25 mg of PGF(2alpha) (PGF) on d 7, and i.m. injection of GnRH (GnRH-2) and timed AI (TAI) 66 h after CIDR removal (d 10). An additional 77 cows not involved in the Presynch comparison were also treated with CO-Synch + CIDR. Pregnancy rates for Presynch (37.3 +/- 6%) and No Presynch (48.5 +/- 6.1%) did not differ (P = 0.6). Pregnancy rate for all CO-Synch + CIDR-treated cattle combined was 41.9 +/- 6.1 (n = 145). In Exp. 2, we examined ovarian events in 98 Brahman x Hereford (F(1)) cows assigned randomly to Presynch or No Presynch. Ovulatory response to GnRH-1 was greater (P < 0.01) in the Presynch (58 +/- 7.1%) than in the No Presynch (27.1 +/- 6.5%) group. However, emergence of a synchronized new follicular wave after GnRH-1 and ovulation rate after GnRH-2 did not differ between groups (P = 0.4). Presynchronization increased the proportion of females ovulating after GnRH-1, but this did not increase synchrony of new follicular wave emergence or ovulation after GnRH-2, and did not improve TAI pregnancy rates.