Effects of heat stress abatement on systemic and mammary inflammation in lactating dairy cows.

To examine the effects of evaporative cooling on systemic and mammary inflammation of lactating dairy cows, 30 multiparous Holstein cows (parity = 2.4, 156 d in milk) were randomly assigned to 1 of 2 treatments: cooling (CL) with fans and misters or not (NC). The experiment was divided into a 10-d baseline when all cows were cooled, followed by a 36-d environmental challenge when cooling was terminated for NC cows. The onset of environmental challenge was considered as d 1. Temperature-humidity index averaged 78.4 during the environmental challenge. Milk yield and dry matter intake (DMI) were recorded daily. Blood and milk samples were collected from a subset of cows (n = 9/treatment) on d -3, 1, 3, 7, 14, and 28 of the experiment to measure cortisol, interleukin 10 (IL10), tumor necrosis factor-α (TNF-α), haptoglobin, and lipopolysaccharide binding protein (LBP). Mammary biopsies were collected from a second subset of cows (n = 6/treatment) on d -9, 2, 10, and 36 to analyze gene expression of cytokines and haptoglobin. A subset of cows (n = 7/treatment) who were not subjected to mammary biopsy collection received a bolus of lipopolysaccharides (LPS) in the left rear quarter on d 30 of the experiment. Blood was sampled from cows and milk samples from the LPS-infused quarter were collected at -4, 0, 3, 6, 12, 24, 48, and 96 h relative to infusion, for analyses of inflammatory products. Deprivation of cooling decreased milk yield and DMI. Compared with CL cows, plasma cortisol concentration of NC cows was higher on d 1 but lower on d 28 of the experiment (cooling × time). Deprivation of cooling did not affect circulating TNF-α, IL10, haptoglobin, or LBP. Compared with CL cows, NC cows tended to have higher milk IL10 concentrations but did not show effects in TNF-α, haptoglobin, or LBP. No differences were observed in mammary tissue gene expression of TNF-α, IL10, and haptoglobin. Milk yield declined after LPS infusion but was not affected by treatment. Compared with CL cows, NC cows had greater milk somatic cell count following intramammary LPS infusion. Non-cooled cows had lower circulating TNF-α and IL10 concentrations and tended to have lower circulating haptoglobin concentrations than CL cows. Milk IL10 and TNF-⍺ concentrations were higher 3 h after LPS infusion for NC cows compared with CL cows. Additionally, NC cows tended to have higher milk haptoglobin concentration after LPS infusion than CL cows. In conclusion, deprivation of evaporative cooling had minimal effects on lactating cows' basal inflammatory status, but upregulated mammary inflammatory responses after intramammary LPS infusion.

Effect of milk replacer feeding rate and frequency of preweaning dairy calves in the southeastern United States: Glucose metabolism.

The objective of this experiment was to examine the effect of milk replacer (MR) feeding rate (FR) and frequency (FF) on glucose metabolism before and after weaning during summer and winter in the subtropical climate of the southeastern United States. Holstein calves (n = 48/season) were enrolled at 8 d of age (DOA) in the summer (June to August, body weight = 40.6 ± 0.7 kg) and winter (November to January, body weight = 41.9 ± 0.8 kg). In each season, calves were randomly assigned to 1 of 4 treatments in a 2 × 2 factorial arrangement including 2 FR [0.65 (low) or 0.76 kg of solids/d (high) of a 26% CP and 17% fat MR] and 2 FF [2× (0700 and 1600 h) or 3× (0700, 1600, and 2200 h)]. Calves were managed similarly and housed in polyethylene hutches bedded with sand. Milk replacer (12.5%) was fed based on treatments until 42 DOA when FR was reduced by half and offered 1×/d (0700 h) for 7 d. Plasma was collected weekly at 1400 h for analyses of glucose and insulin concentrations in all calves. Pre- and postprandial glucose and insulin concentrations of a subset of calves (n = 10/treatment per season) were measured on 20 DOA. A subset of calves (n = 8/treatment per season) was subjected to an intravenous glucose tolerance test (GTT) on 27 and 57 DOA and insulin challenge on 28 and 58 DOA at 1030 h. Average ambient temperature was 26.1 ± 2.2°C in summer and 12.9 ± 5.4°C in winter. During the preweaning period in both seasons, feeding high increased plasma glucose concentrations compared with low, and increasing FF reduced basal insulin concentrations. Compared with 2×, feeding 3× did not affect postprandial glucose but lowered insulin in the summer, whereas in the winter, increased glucose from 30 to 180 min but lowered insulin from 240 to 420 min after MR feeding. Following GTT before weaning in both seasons, 3× reduced insulin increment and area under the curve compared with 2× without affecting glucose disposal. After weaning, treatment did not affect glucose disposal or insulin responses after GTT during winter, but calves fed 3× had faster glucose disposal and stronger insulin responses than 2× during summer. In both summer and winter, preweaned calves fed 3× had greater decrement and area under the curve of plasma glucose after insulin challenge, suggesting enhanced peripheral tissue insulin response compared with 2×. This effect persisted after weaning only during summer. Increasing FR had no effect on metabolic responses in both seasons. In conclusion, increasing MR FF from 2 to 3 times per day reduced insulin secretion but enhanced insulin response on peripheral tissues of preweaned calves regardless of season.

Effects of milk replacer feeding rate and frequency of preweaning dairy calves in the southeastern United States: Performance, abomasal emptying, and nutrient digestibility.

To evaluate the effects of milk replacer (MR) feeding rate (FR) and frequency (FF) on performance, abomasal emptying, and nutrient digestibility in the southeastern United States, Holstein calves (n = 48/season) were enrolled at 8 d of age (DOA) during summer [June to August, body weight (BW; mean ± SD) = 40.71 ± 4.35 kg] and winter (November to January, BW = 42.03 ± 3.83 kg). Within season, calves were randomly assigned to 1 of 4 treatments in a 2 × 2 factorial arrangement including 2 FR [0.65 (low) or 0.76 kg of solid per day (high) of a 26% crude protein and 17% fat MR], and 2 FF [2× (0700 and 1600 h) or 3× (0700, 1600, and 2200 h) daily]. Calves were housed in polyethylene hutches and managed similarly throughout the trial. Milk replacer (12.5% solids) was fed to calves based on their respective treatments until 42 DOA, when MR allowance was reduced by 50% and offered once a day (0700 h) for the following 7 d until weaning. Calves remained on trial until 63 DOA. Calf starter and water were offered ad libitum. Ambient temperature and relative humidity inside and outside hutches were measured hourly. Starter and MR intakes were recorded daily. Respiration rate and rectal temperature were recorded 3 times a week. Structural growth and BW were measured weekly. Acetaminophen (50 mg/kg of BW) mixed with MR was fed to a subset of calves (0700 h, n = 10/treatment per season) on 20 DOA. Plasma was collected at 15, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 360, 420, and 480 min after feeding, to analyze acetaminophen. The acetaminophen concentration-time curve was modeled to the first derivative of Siegel's modified power exponential equation, and the time for plasma acetaminophen to reach maximum (Tmax) was calculated to evaluate abomasal emptying rate. During the pre- (14.9-17.9 DOA) and postweaning (51.0-54.0 DOA) periods, a subset (n = 8/treatment per season) of calves was used to determine the apparent digestibility of nutrients, using chromic oxide as the external marker. Feeding 3× reduced preweaning respiration rate during summer and reduced rectal temperature during winter. Increasing FR improved BW gain and structural growth. Feeding more times per day tended to improve growth during winter but not summer. We found no effect of treatment on nutrient digestibility. Increasing FR had no effect on Tmax during winter but tended to delay Tmax of plasma acetaminophen during summer. Regardless of season, increasing FF lowered Tmax of plasma acetaminophen. In conclusion, increasing FF accelerated abomasal emptying and might reduce heat load of preweaning dairy calves but improved growth only during winter. Increased MR allowance improved growth in both seasons but delayed abomasal emptying only under heat stress conditions.

Impact of heat stress and a feed supplement on hormonal and inflammatory responses of dairy cows.

The aim of this trial was to evaluate the effects of an immunomodulatory supplement (OmniGen AF, OG; Phibro Animal Health Corp.) and heat stress on hormonal, inflammatory, and immunological responses of lactating dairy cows. Sixty multiparous Holstein cows were randomly assigned to 4 treatments in a 2 × 2 factorial arrangement using 2 environments: cooled using fans and misters, or noncooled, and 2 top-dressed feed supplements (56 g/d): OG or a placebo (CTL). Temperature-humidity index averaged 78 during the 8-wk trial. Blood was drawn to analyze cortisol, prolactin, and circulating tumor necrosis factor (TNF)-α and IL-10. Peripheral blood mononuclear cells (PBMC) were isolated and stimulated with hydrocortisone, prolactin, or lipopolysaccharide (LPS), individually or in several combinations, to assess induced proliferation and cytokine production. At d 52, 6 cows per treatment were injected i.v. with an LPS bolus (ivLPS) to assess hormone and cytokine responses. For cooled cows, feeding OG increased plasma cortisol concentration relative to CTL. Noncooled cows fed CTL had lower circulating TNF-α concentrations than noncooled-OG and cooled-CTL cows, with cooled-OG intermediate. Hydrocortisone+LPS-stimulated PBMC from OG cows tended to proliferate more than CTL. Relative to cooled cows, PBMC from noncooled cows produced more TNF-α and IL-10 when stimulated with LPS. Following ivLPS, cooled-OG cows had a greater cortisol response than the other treatments. In conclusion, OG supplementation enhanced cortisol release under basal condition and induced inflammation with cooling compared with CTL. This suggests that heat stress inhibits OG-mediated cortisol release. Heat stress seemed to enhance the inflammatory responses of PBMC from lactating cows. However, OG supplementation promoted PBMC proliferation under stress, or in the presence of hydrocortisone.

Incidence of cervical intraepithelial neoplasia in a cohort of HIV-infected women.

OBJECTIVE: To assess cervical intraepithelial neoplasia (CIN) incidence in HIV-positive women and the risk factors for these lesions. METHODS: A retrospective and longitudinal cohort study was conducted from June 13, 1997, to December 18, 2009. At the first visit, the 348 participants had a normal cytologic finding but a negative Schiller test result, or an abnormal cytologic finding but no histologic diagnosis of CIN. Infection with HPV was detected by polymerase chain reaction. The main outcome measure was CIN incidence. RESULTS: During a mean follow-up of 40 months, 47 women (13.5%) developed CIN, for an incidence of 4.1 cases per 100 person-years of follow-up. The HPV prevalence was 68.1%, 42 women (89.4%) developed CIN 1, and no invasive cervical cancers were identified. On multivariate analysis, women younger than 19 years at first sexual intercourse (RR, 2.6; 95% CI, 1.24-5.35) and women who had never used antiretrovirals or used them only during pregnancy (RR, 2.3; 95% CI, 1.31-4.19) were at higher risk for CIN. CONCLUSION: The CIN incidence was low despite the high HPV prevalence. Being younger than 19 years at first sexual intercourse and not using antiretroviral medications were found to be the main risk factors for CIN.

Postpartum changes in plasma viral load and CD4 percentage among HIV-infected women from Latin American and Caribbean countries: the NISDI Perinatal Study.

The goal of this study was to evaluate changes in plasma human immunodeficiency virus (HIV) RNA concentration [viral load (VL)] and CD4+ percentage (CD4%) during 6-12 weeks postpartum (PP) among HIV-infected women and to assess differences according to the reason for receipt of antiretrovirals (ARVs) during pregnancy [prophylaxis (PR) vs. treatment (TR)]. Data from a prospective cohort of HIV-infected pregnant women (National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study) were analyzed. Women experiencing their first pregnancy who received ARVs for PR (started during pregnancy, stopped PP) or for TR (initiated prior to pregnancy and/or continued PP) were included and were followed PP. Increases in plasma VL (> 0.5 log10) and decreases in CD4% (> 20% relative decrease in CD4%) between hospital discharge (HD) and PP were assessed. Of the 1,229 women enrolled, 1,119 met the inclusion criteria (PR: 601; TR: 518). At enrollment, 87% were asymptomatic. The median CD4% values were: HD [34% (PR); 25% (TR)] and PP [29% (PR); 24% (TR)]. The VL increases were 60% (PR) and 19% (TR) (p < 0.0001). The CD4% decreases were 36% (PR) and 18% (TR) (p < 0.0001). Women receiving PR were more likely to exhibit an increase in VL [adjusted odds ratio (AOR) 7.7 (95% CI: 5.5-10.9) and a CD4% decrease (AOR 2.3; 95% CI: 1.6-3.2). Women receiving PR are more likely to have VL increases and CD4% decreases compared to those receiving TR. The clinical implications of these VL and CD4% changes remain to be explored.

Postpartum changes in plasma viral load and CD4 percentage among HIV-infected women from Latin American and Caribbean countries: the NISDI Perinatal Study

The goal of this study was to evaluate changes in plasma human immunodeficiency virus (HIV) RNA concentration [viral load (VL)] and CD4+ percentage (CD4 percent) during 6-12 weeks postpartum (PP) among HIV-infected women and to assess differences according to the reason for receipt of antiretrovirals (ARVs) during pregnancy [prophylaxis (PR) vs. treatment (TR)]. Data from a prospective cohort of HIV-infected pregnant women (National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study) were analyzed. Women experiencing their first pregnancy who received ARVs for PR (started during pregnancy, stopped PP) or for TR (initiated prior to pregnancy and/or continued PP) were included and were followed PP. Increases in plasma VL (> 0.5 log10) and decreases in CD4 percent (> 20 percent relative decrease in CD4 percent) between hospital discharge (HD) and PP were assessed. Of the 1,229 women enrolled, 1,119 met the inclusion criteria (PR: 601; TR: 518). At enrollment, 87 percent were asymptomatic. The median CD4 percent values were: HD [34 percent (PR); 25 percent (TR)] and PP [29 percent (PR); 24 percent (TR)]. The VL increases were 60 percent (PR) and 19 percent (TR) (p < 0.0001). The CD4 percent decreases were 36 percent (PR) and 18 percent (TR) (p < 0.0001). Women receiving PR were more likely to exhibit an increase in VL [adjusted odds ratio (AOR) 7.7 (95 percent CI: 5.5-10.9) and a CD4 percent decrease (AOR 2.3; 95 percent CI: 1.6-3.2). Women receiving PR are more likely to have VL increases and CD4 percent decreases compared to those receiving TR. The clinical implications of these VL and CD4 percent changes remain to be explored.

Behavior surveillance: prevalence and factors associated with high-risk sexual behavior among HIV-infected men in Brazil in the post-HAART era.

A cross-sectional analysis was conducted to describe unsafe sexual practices among HIV-infected men under care in two Brazilian urban areas. Data were collected by face-to-face interviews. Twenty-five percent practiced unprotected sex in the previous year, 16% were abstinent, 33% had sex with men only, 45% with women only, 48% had male/female stable partners, 84% were on HAART and 48% had AIDS. Illicit drug use, number of female partners, having stable partners, and STD diagnosis were associated with unsafe sex. Interventions to reduce risk taking behavior among HIV-positive men under care in these settings are urgent, especially among heterosexual stable couples.

Persistence of genotypic resistance to nelfinavir among women exposed to prophylactic antiretroviral therapy during pregnancy.

We assessed the development of drug resistance in women exposed to antiretroviral therapy (ART) for prevention of mother-to-child transmission (PMTCT) after 24 weeks postpartum in a prospective cohort of HIV-1-infected women. HIV-1-infected women, who received prophylactic ART during pregnancy, had genotypic resistance testing performed at the start (T1) of and 24 weeks after ART interruption (T2). The women had CD4 counts >250 cells/ml and no AIDS defining conditions. Of the 30 eligible women, the median age was 27 years [25-75% interquartile range (IQR): 21-32] and the median gestational age of ART initiation was 22 weeks (IQR: 19-27): 19 (63.3%) received zidovudine (ZDV) plus lamivudine (3TC) plus nelfinavir (NFV). At entry, most women (96.7%) were asymptomatic (CDC93 A1/A2), with a median CD4 count of 446 (IQR: 353-686) and median viral load (VL) of 8560 copies/ml (IQR: 3,252-19,515). No HIV-1 vertical transmission was observed. HIV subtype B was the most prevalent (70%). The development of new mutations associated with ART resistance was analyzed at T2. NFV resistance was observed in 4 out of 17 (23.5%) patients exposed to this drug: two major mutations D30N (1/17) and L90M (1/17) and minor mutations (N88S, 2/17). Mutations on positions 44, 69, and 118 (1/28) were present on reverse transcriptase (RT) analysis. No new nonnucleoside reverse transcriptase inhibitor (NNRTI)-associated mutation was observed. In this cohort, ART regimens were very efficient at blocking HIV vertical transmission. However, the high rate of NFV-resistant mutations observed in the postpartum period indicates the need for discussion of ART choices during pregnancy and the potential impact on future therapeutic options for these women. Women previously exposed to ART for PMTCT who will start HIV treatment should have genotypic resistance testing performed.

Maternal antiretroviral drugs during pregnancy and infant low birth weight and preterm birth.

OBJECTIVE: To determine the relationship between maternal antiretroviral regimens during pregnancy and adverse infant outcomes [low birth weight (LBW) and preterm birth]. The a priori hypothesis was that protease inhibitor (PI)-containing regimens are associated with an increased risk of LBW and preterm birth. DESIGN: Prospective cohort study of HIV-1-infected women and their infants (NISDI Perinatal Study). METHODS: Data were analysed from 681 women receiving at least one antiretroviral drug [in order of increasing complexity: one or two nucleoside reverse transcriptase inhibitors (1-2 NRTI), two NRTI plus one non-nucleoside reverse transcriptase inhibitor (NNRTI) (HAART/NNRTI), or two NRTI plus one PI (HAART/PI)] for at least 28 days during pregnancy, and who delivered live born, singleton infants with known birth weight and gestational age by 1 March 2005. Multivariable logistic regression modeling was used to assess the relationship of maternal ART with LBW and with preterm birth, adjusting for covariates. RESULTS: The incidence of LBW and preterm birth, respectively, was 9.6% and 7.4% (1-2 NRTI), 7.4% and 5.8% (HAART/NNRTI), and 16.7% and 10.6% (HAART/PI). There was no statistically significant increased risk of LBW [adjusted odds ratio (AOR), 1.5; 95% confidence interval (95% CI), 0.7-3.2] or preterm birth (AOR, 1.1; 95% CI, 0.5-2.8) among women who received HAART/PI compared with women receiving 1-2 NRTI. CONCLUSIONS: Among a population of HIV-1-infected women in Latin America and the Caribbean, maternal receipt of PI-containing ART regimens during pregnancy was not associated with a statistically significant increase in risk of LBW or preterm birth.

Mode of delivery and postpartum morbidity in Latin American and Caribbean countries among women who are infected with human immunodeficiency virus-1: the NICHD International Site Development Initiative (NISDI) Perinatal Study.

OBJECTIVE: The purpose of this study was to test whether cesarean delivery before labor and before ruptured membranes is associated with a higher risk of postpartum morbidity than vaginal delivery among women who are infected with human immunodeficiency virus-1 in Latin America and the Caribbean. STUDY DESIGN: Data from a prospective cohort study (National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study) were analyzed. The study population consisted of women who were followed for > or = 6 to 12 weeks after delivery, who had singleton infants, and with a known mode of delivery. RESULTS: Of 819 enrollees, 697 women met inclusion criteria (299 vaginal deliveries, 260 cesarean deliveries before labor and before ruptured membranes, 138 cesarean deliveries after labor and/or after ruptured membranes); 36 women (5%) had postpartum morbidity (18 major, 18 minor). Mode of delivery was associated with postpartum morbidity (P = .02). Unadjusted odds ratios (95% CIs) for postpartum morbidity according to mode of delivery were cesarean delivery before labor and before ruptured membranes (odds ratio, 1.16 [95% CI, 0.5, 2.7]), cesarean delivery after labor and/or after ruptured membranes (odds ratio, 2.96 [95% CI, 1.3, 6.7]), and vaginal delivery (reference). These results did not differ appreciably with covariate adjustment. CONCLUSION: The rate of postpartum morbidity was low. Mode of delivery was associated with postpartum morbidity, possibly reflecting the larger proportion of minor postpartum morbidity events among those with cesarean delivery after labor and/or after ruptured membranes.

Captaçäo de células endovervicais colunares na colheita colpocitógica: o estudo comparativo de uma espátula de Ayre modificada / Capture of endocervical columnar cells in the cervical cytology colletion: the study of a modified Ayre spatula

Os autores transformaram a espátula de Ayre Original visando otimizar a colheita endocervical. O estudo verificou se a habilidade da espátula modificada em colher células endocervicais colunares é próxima da obtida pela combinaçäo espátula Ayre-Cytobrush e melhor do que a da espátula de Ayre. Foram avaliados 276 esfregaços. A combinaçäo espátula de Ayre-Cytobrush apresentou o melhor desempenho na produçäo de células endocervicais colunares. Quando comparada à combinaçäo espátula de Ayre-Cytobrush, a espátula modificada produziu menor sangramento (x²=7,98;p=0,004) e näo foi inferior na produçäo de grupos de células endocervicais colunares de escore III (x²=0,26;p=0,6). Quando defrontada com a espátula de Ayre, foi estatisticamente superior na produçäo de densidade celular endocervical (t=5,96;p<0,001) e de grupos de células endocervicais colunares dos escores I, II e III (x²=6,94,p=0,008;x²=24,40,p=0,0000008 e x²=9,59, p=0,002, respectivamente). Conclui-se que a espátula modificada de Ayre, podendo ser utilizada em populaçöes onde o uso do Cytobrush for impossível

Taquicardia ventricular paroxística durante a gravidez após infarto agudo do miocárdio complicado por formaçäo de aneurisma ventricular / Paroxysmal ventricular tachycardia during pregnancy after acute myocardial infarction complicated with formation of ventricular aneurysm

Taquicardia ventricular paroxística durante a gravidez, secundária a infarto agudo do miocárdio complicado por formaçao de aneurisma em ventrículo esquerdo é incomum. É descrito um caso desta perigosa associaçao com ênfase para sua conduçao e as complicaçoes maternas e fetais.