Developmental immunotoxicity of atrazine in rodents

There is a substantial literature reporting that the developing immune system is more sensitive to toxic insult and that the measurable phenotype resulting from prenatal/neonatal exposure often differs from that seen in adult exposure models (reviewed in Holladay and Steven, and Smialowicz et al.). Atrazine is a common herbicidal contaminant of groundwater in agricultural areas in the USA. The potential immunotoxicity of atrazine has been extensively studied using adult-exposure models; however, few studies have explored its immunotoxicity in a prenatal and/or lactational exposure model. Prenatal/lactational atrazine exposure affects the function of young adult rodent immune systems in both sex- and age-dependant manners. In our studies, the humoural and cell-mediated immune responses of offspring from atrazine-exposed dams were assessed at two ages, 3 and 6 months of age to test the hypothesis that prenatal/lactational atrazine exposure would cause greater health complications as the mice aged. Male offspring showed a significant immunopotentiation at three moa that was not apparent at 6 months. Three-month-old female offspring showed no significant difference in immune response from controls. However, at 6 months, female litter mates showed a significant depression in their immune function. These results indicate a decreasing trend in immune capacity. Rooney et al. showed a significant depression of the immune function of young male rat exposure prenatally and lactationally to atrazine. These results demonstrate a sex- and age-dependant effect of prenatal exposure to atrazine on the immune system of the adult offspring using two rodent strains.     

Using data linkage to improve the completeness of Aboriginal and Torres Strait Islander status in communicable disease notifications in Victoria

Objective : The burden of notifiable diseases in Aboriginal and Torres Strait Islander Victorians cannot be accurately estimated due to under‐reporting of Indigenous status. We used data linkage to improve completeness of Indigenous status in people notified with viral hepatitis and gonococcal infection. Methods : Notifications made between 2009 and 2010 were linked with Victorian hospitalisation data (1997–2011). Notification rates by Indigenous status and rate ratios were calculated before and after linkage. Results : There were 12,448 cases of hepatitis B, hepatitis C and gonococcal infection notified in Victoria in 2009–2010, with Indigenous status missing in 61.6%, 67.8%, 33.1% of these conditions, respectively. Of the total notified cases, 82% were able to be linked. Following linkage, the proportion of notifications with missing Indigenous status decreased to less than 0.2% for all conditions. Age‐standardised notification rates among both Aboriginal people and non‐Aboriginal people increased for all conditions. Conclusions : Data linkage improved completeness of Indigenous status in notifications for viral hepatitis and gonococcal infection in Victoria. Completeness of these data is integral to monitoring progress in closing the Indigenous life expectancy gap. Implications : Greater emphasis is needed on addressing prevention, treatment and care for viral hepatitis and sexually transmissible infections for Indigenous Victorians.     

人参皂甙诱导的造血细胞内信号传递途径的研究

目的探讨人参皂甙（ＧＳ）刺激造血祖细胞增殖有关的细胞内信号传递途径。方法采用Ｎｏｒｔｈｅｒｎ印迹杂交法、电泳带移动阻滞实验、抗体胶结合移动实验和紫外放射交联实验。结果ＮｏｒｔｈｅｒｎＢｌｏｔ显示经ＧＳ诱导的人巨核细胞株ＣＨＲＦ２８８、Ｍｅｇ０１和ＭＯ７ｅ细胞的ＧＡＴＡ２ｍＲＮＡ水平增高,分别是未经处理细胞的１．８４,２．４３和１．５２倍。但ＧＡＴＡ１ｍＲＮＡ表达水平低,且ＧＳ处理前后也无明显变化。电泳带移动阻滞实验提示ＧＳ诱导的细胞核内ＧＡＴＡ转录调控蛋白与特定的ＤＮＡ序列结合的活性增高。抗体胶结合移动实验证实与ＤＮＡ结合的主要成分为ＧＡＴＡ２蛋白,紫外放射交联实验确定该复合物的相对分子质量约为５０×１０３,符合ＧＡＴＡ２转录调控蛋白。结论ＧＳ诱导细胞内的信号传递途径与转录因子ＧＡＴＡ２有关,ＧＡＴＡ２有介导ＧＳ刺激造血细胞增殖的作用。     

Resistance to ciprofioxacin in non-typhoidal salmonellas from humans in England and Wales—the current situation

Objective: To report on the prevalence of isolates with ciprofloxacin resistance in non-typhoidal salmonellas from humans in England and Wales in 1997.
Methods: All non-typhoidal salmonellas referred to the Laboratory of Enteric Pathogens in 1997 were screened for resistance to ciprofloxacin at 0.125 and 1.0 mg/L and nalidixic acid at 16 mg/L, and results were compared to those for 1994. Full minimal inhibitory concentrations (MICs) of these antimicrobials were also determined for a selection of isolates resistant to ciprofloxacin at 0.125 mg/L but sensitive at 1.0 mg/L, and for all isolates resistant at 1.0 mg/L.
Results: Since 1994 there have been increases in the occurrence of resistance to ciprofloxacin (MICs: 0.25–1.0 mg/L) in Salmonella enterica serotypes Enteritidis, Typhimurium, Virchow and Hadar. Of particular importance have been increases in the occurrence of resistance in multiresistant S. Typhimurium DT 104, and also in S. virchow, a serotype with a propensity for causing extraintestinal infections in humans. High-level resistance (MIC≥2.0 mg/L) was uncommon and was identified in only a few strains, all from patients with a history of recent foreign travel.
Conclusions: There is a strong temporal association between increases in the occurrence of ciprofloxacin resistance in Salmonella serotypes Typhimurium, Virchow and Hadar from humans in England and Wales and with the licensing for use in food animals in the UK of the related fluoroquinolone antibiotic enrofloxacin; in contrast, for S. enteritidis ciprofloxacin resistance was most common in a phage type associated with foreign travel. It is hoped that recent recommendations for the use of fluoroquinolone antimicrobials in food animals in the UK will result in a reduction in the occurrence of resistance to ciprofloxacin in zoonotic salmonellas causing infections in humans.     

Neuropsychological sequelae of haemolytic uraemic syndrome

BACKGROUND—Severe haemolytic uraemic syndrome (HUS) in childhood can cause stroke, hemiplegia, cortical blindness, and psychomotor retardation. These outcomes are evident at the time of discharge immediately after the acute illness. Less is known about the neuropsychological outcomes of less severely affected children who recover from acute HUS.AIMS—This multicentre case control study investigated the hypothesis that children who survive an acute episode of HUS without recognisable neurological injuries have greater impairment of cognitive, academic, and behavioural functions than controls.DESIGN—Children with HUS were eligible if they had no evidence of severe neurological dysfunction when discharged from one of six Canadian hospitals. Controls had been admitted to hospital for a non-HUS illness and were matched by age, sex, first language, and socioeconomic status. All subjects underwent evaluation of behaviour, academic achievement, cognitive function, and verbal abilities using standardised tests administered by a psychometrist blinded to the case or control status.RESULTS—Ninety one case control pairs were enrolled. No important differences between patients with HUS and paired controls were evident on tests of IQ, behaviour, verbal abilities, or academic achievement. There was no increased risk of attention deficit disorder among patients with HUS. There was no correlation between the severity of acute renal failure and neuropsychological measures, although scores on some verbal ability tests were lower in those with the highest serum creatinine concentrations during illness.CONCLUSIONS—Children discharged from hospital without apparent neurological injury after an episode of acute HUS do not have an increased risk of subclinical problems with learning, behaviour, or attention.     

Readiness to perform cardiopulmonary resuscitation: an emerging strategy against sudden cardiac death.

OBJECTIVES: This investigation assessed motivational factors and psychosocial barriers that affect individual readiness to perform cardiopulmonary resuscitation (CPR). This is the first study to use the Transtheoretical model in assessing readiness to perform CPR. METHODS: A sample of 786 subjects, > or = 45 years of age and who resided in a private residence, were randomly selected to participate in a structured telephone interview. Data on motivational readiness, emotional state, perceived psychosocial barriers, and perceived efficacy in performing CPR were collected using dichotomous and Likert-type ratings. RESULTS: Subjects with greater motivational readiness expected to experience significantly fewer symptoms of emotional distress during a cardiac emergency and to encounter fewer psychosocial barriers. This group also reported greater efficacy in their ability to perform CPR. These findings were independent of gender, medical history, age, and educational level. CONCLUSIONS: Meaningful differences are apparent in individual readiness to perform CPR. These findings provide additional support for the need to tailor CPR training strategies using behavioral methods that enhance motivational readiness and decrease apprehension about anticipated emotional distress and psychosocial barriers.     

Prostacyclin concentrations and transitional circulation in preterm infants requiring mechanical ventilation.

AIM: To describe the association between early postnatal prostacyclin concentrations in preterm infants; echocardiographic measurements of ductal diameter and ventricular output and clinical outcomes of intraventricular haemorrhage (IVH) and patent ductus arteriosus (PDA). METHODS: Forty nine preterm infants born before 30 weeks of gestational age (median birthweight 980 g, median gestational age 27 weeks) underwent echocardiographic studies at 5, 12, 24 and 48 hours of postnatal age. Measurements included ventricular outputs and the ductal shunt diameter as a measure of the shunt size. Simultaneous measurements of blood pressures, mean airway pressure and inspired fraction of oxygen (FIO2) were recorded. A blood sample for the prostacyclin metabolite 6-ketoprostaglandin F1-alpha (6KPGF1 alpha) was taken at the 5 and 24 hour echocardiogram. RESULTS: The mean 6KPGF1 alpha concentrations were higher than adult concentrations at 5 (515 pg/ml) and 24 (255 pg/ml) hours. There was no association with gestational age. Raised 6KPGF1 alpha concentrations were related to increased need for mechanical ventilation and severity of respiratory disease. At 5 hours, increased 6KPGF1 alpha concentrations were associated with larger PDA and at 24 hours with larger PDA and higher left ventricular output. Infants with higher 6KPGF1 alpha concentrations were more likely to develop clinically significant PDA. There was no association between early measurements of 6KPGF1 alpha and IVH. CONCLUSIONS: Early postnatal prostacyclin concentrations are markedly raised in preterm infants, particularly in those with more severe lung disease. Raised 6KPGF1 alpha concentrations were associated with an increased ductal diameter and subsequent PDA, but not IVH.     

The incidence of spontaneous acrosome reaction in homogeneous populations of hyperactivated human spermatozoa.

The incidence of spontaneous acrosome reaction occurring in 1314 individually selected hyperactivated (HA) human spermatozoa was compared to that occurring in 8226 individually selected non-hyperactivated spermatozoa (non-HA) sampled over an incubation time course to allow for capacitation. Two-way analysis of variance showed a significant difference between HA and non-HA spermatozoa for the mean percent acrosome reacted (R), partially acrosome reacted (PR) and combined total (R+PR) (P < 0.001). One-way analysis showed that among the HA spermatozoa there were marked differences among the proportion showing R+PR at the various time points (P = 0.005). Using the same end point, there was no significant evidence of change with time for the non-HA spermatozoa. The overall data indicated that HA human spermatozoa have a greater propensity for spontaneous acrosomal loss than non-HA spermatozoa during incubation in synthetic culture media.