Chlamydia pneumoniae can infect the central nervous system via the olfactory and trigeminal nerves and contributes to Alzheimer's disease risk.

Chlamydia pneumoniae is a respiratory tract pathogen but can also infect the central nervous system (CNS). Recently, the link between C. pneumoniae CNS infection and late-onset dementia has become increasingly evident. In mice, CNS infection has been shown to occur weeks to months after intranasal inoculation. By isolating live C. pneumoniae from tissues and using immunohistochemistry, we show that C. pneumoniae can infect the olfactory and trigeminal nerves, olfactory bulb and brain within 72 h in mice. C. pneumoniae infection also resulted in dysregulation of key pathways involved in Alzheimer's disease pathogenesis at 7 and 28 days after inoculation. Interestingly, amyloid beta accumulations were also detected adjacent to the C. pneumoniae inclusions in the olfactory system. Furthermore, injury to the nasal epithelium resulted in increased peripheral nerve and olfactory bulb infection, but did not alter general CNS infection. In vitro, C. pneumoniae was able to infect peripheral nerve and CNS glia. In summary, the nerves extending between the nasal cavity and the brain constitute invasion paths by which C. pneumoniae can rapidly invade the CNS likely by surviving in glia and leading to Aß deposition.

Weight loss after diagnosis with gestational diabetes and birth weight among overweight and obese women.

To determine if, among overweight or obese women with gestational diabetes (GDM), weight loss after GDM diagnosis is associated with lower infant birth weight within levels of overweight or obesity class. Overweight and obese women with singleton pregnancies managed for GDM at a large diabetes and pregnancy program located in Charlotte, NC between November 2000 and April 2010, were eligible for this retrospective cohort study. All were managed using a rigorous standardized clinical protocol. Clinical information including maternal pre-pregnancy body mass index, gestational weight gain, treatment, and medical and obstetric history was abstracted from medical records. The association of weight loss after GDM diagnosis and birth weight was analyzed using linear regression stratified by maternal pre-pregnancy overweight or obesity class (I, II/III). Of the 322 women in this study 19 % lost weight between diagnosis of GDM and delivery. After adjustment for maternal age, parity, race/ethnicity, gestational week at first hemoglobin A1c (A1C), A1C at diagnosis, weight gain prior to GDM, treatment with insulin or oral hypoglycemic agents, gestational age at delivery, and infant sex, weight loss was associated with 238.3 g lower mean infant birth weight among overweight women (95 % CI -393.72, -82.95 g), but was not associated with lower mean infant birth weight among obese class II/III women (95 % CI -275.61, 315.38 g). Weight loss, after diagnosis of GDM, is associated with lower infant birth weight among overweight women, but not among obese class II/III women.

Antenatal haemoglobin A1c and risk of large-for-gestational-age infants in a multi-ethnic cohort of women with gestational diabetes.

Gestational diabetes mellitus (GDM) is a risk factor for delivering a large-for-gestational-age (LGA) infant. Haemoglobin A1c (A1C) is an indicator of glycaemic control. The objective of this study was to test whether higher A1C quartile at the time of diagnosis of GDM is associated with increased risk of delivering a LGA or macrosomic infant. Women with singleton pregnancies treated for GDM at a large diabetes and pregnancy programme located in Charlotte, North Carolina, were eligible for inclusion in this retrospective cohort study. Clinical information, including A1C at diagnosis, treatment, prior medical and obstetric history, and birth data were abstracted from medical records. LGA was defined as birthweight >90th percentile for gestational age and sex and macrosomia as birthweight >4000 g. Logistic regression was used to analyse the association of A1C at GDM diagnosis with risk of delivering LGA or macrosomic infants. This study included 502 women. Prevalences of LGA and macrosomia were 4% and 6% respectively. After adjustment there was no detectable trend of increased risk for LGA (P for trend = 0.12) or macrosomia (P for trend = 0.20) across increasing quartiles of A1C at GDM diagnosis. A1C at GDM diagnosis may not be linearly associated with LGA or macrosomia, possibly because of the mediating effect of strict glycaemic control in this clinical setting.

Hemoglobin A1c and postpartum abnormal glucose tolerance among women with gestational diabetes mellitus.

OBJECTIVE: To analyze the association of hemoglobin A1c (HbA1c) at gestational diabetes mellitus (GDM) diagnosis with postpartum abnormal glucose in a cohort of women with GDM. METHODS: Women with singleton pregnancies treated for GDM at a large diabetes and pregnancy program located in Charlotte, North Carolina, who completed a postpartum 2-hour oral glucose tolerance test were eligible for inclusion in this retrospective cohort study. Clinical information, including maternal HbA1c at diagnosis, was abstracted from medical records. A parametric survival model was used to assess the association of HbA1c at GDM diagnosis with postpartum maternal abnormal glucose including impaired fasting glucose, impaired glucose tolerance, and any postpartum abnormal glucose. RESULTS: Of the 277 postpartum women with GDM, 75 (32%) had impaired fasting glucose, 61 (28%) had impaired glucose tolerance, and 15 (9%) were diagnosed with type 2 diabetes mellitus after delivery. After adjustment for clinic, maternal age, parity, prepregnancy body mass index 25 or higher, nonwhite race or ethnicity, and gestational week at first HbA1c, we detected a trend of increased risk for impaired fasting glucose (P=.01), impaired glucose tolerance (P=.002), and any glucose abnormality (P<.001) associated with increased quartile of HbA1c at GDM diagnosis. CONCLUSION: Hemoglobin A1c measured at GDM diagnosis may be a useful tool for identifying patients with GDM at highest risk of developing postpartum abnormal glucose.

Antepartum A1C, maternal diabetes outcomes, and selected offspring outcomes: an epidemiological review.

Between 1989 and 2004, the prevalence of gestational diabetes mellitus (GDM) in the United States increased by 122%. Glycated haemoglobin, as measured by haemoglobin A1C (A1C), can potentially identify pregnant women at high risk for adverse outcomes associated with GDM including macrosomia and post-partum glucose intolerance. Our objective was to systematically review the literature with respect to A1C levels during pregnancy and associated maternal and offspring outcomes. We used MEDLINE to identify relevant publications from 1975 to 2009. We included articles if they met the following criteria: original full text articles in English; primary exposure of antepartum A1C; women with GDM at baseline or who developed GDM during the study; primary outcome of GDM, insulin use, post-partum abnormal glucose or type 2 diabetes (T2DM), birthweight, macrosomia or large for gestational age. Case series and case reports were excluded. Twenty studies met our criteria. A1C at GDM diagnosis was positively associated with post-partum abnormal glucose. Women with post-partum T2DM or impaired glucose tolerance had mean A1C at GDM diagnosis higher than those with normal post-partum glucose (P ≤ 0.002) and a 1% increase in A1C at GDM diagnosis was associated with 2.36 times higher odds of post-partum abnormal glucose 6 weeks after delivery [95% confidence interval 1.19, 4.68]. The association of A1C and birthweight varied substantially between studies, with correlation coefficients ranging from 0.11 to 0.51. A1C, a less burdensome and costly measure than an oral glucose tolerance test, appears to be an attractive measure for identifying women at high risk of adverse outcomes associated with GDM.

New measures of diabetes self-care agency, diabetes self-efficacy, and diabetes self-management for insulin-treated individuals with type 2 diabetes.

AIMS AND OBJECTIVES: To develop and refine three new scales that measure diabetes self-care agency, diabetes self-efficacy and diabetes self-management to reflect the American Diabetes Association current standards of diabetes care and the American Association of Diabetes Educators self-care behaviours. And, to establish the clarity, consistency and content validity of the scales. BACKGROUND: There is a need to have valid and reliable instruments or scales to assess an individual's diabetes self-care agency, self-efficacy and self-management to plan appropriate interventions that can be effective in improving glycaemic control and delaying or preventing diabetes-related complications. DESIGN: A methodological design was used to conduct this study. METHODS: Ten clinicians and 10 insulin-treated individuals with type 2 diabetes (T2DM) from a diabetes care center in the southern USA participated in this study. Analysis consisted of inter-rater agreement to determine clarity and consistency with standards of diabetes care and content validity of individual items on the scales (I-CVI) and the overall scales (S-CVI/Ave) to determine relevance for current diabetes care practice. RESULTS: All I-CVI and S-CVI/Ave of the DSES exceeded the minimum acceptable criteria. All I-CVI and the S-CVI of the DSMS also exceeded the minimum accepted criteria, except for one item that had I-CVI = 0.70. Evaluation of the items and the directions of the scales by the sample of insulin-treated individuals with T2DM exceeded the minimum criteria of 80% inter-rater agreement. RELEVANCE TO RESEARCH AND CLINICAL PRACTICE: Further psychometric testing of the scales with samples of insulin-treated individuals with diabetes is warranted and will lay the groundwork for further research and clinical practice to enhance the capability, confidence and actual performance of diabetes self-management activities among insulin-treated individuals with T2DM. CONCLUSIONS: The scales can be used by diabetes care providers to assess and follow-up individuals with diabetes who need intense case management. They also can be the measures of choice to conduct future research to test the effects of interventions among insulin-treated individuals with T2DM.

Serotipos y genotipos de virus dengue circulantes en Venezuela, 1990 - 1997 / Serotypes and genotypes of dengue virus circulating in Venezuela, 1990 - 1997

Debido a la severidad de las epidemias de dengue hemorrágico registradas en los últimos años en Venezuela, se realizó el análisis retrospectivo de los serotipos de virus dengue circulante en el país y la evolución epidemiológica molecular del serotipo dengue 2. Los resultados presentados indican que los virus dengue tipos 1, 2 y 4 son endémicos en Venezuela y circulan simultáneamente durante todo el año en las grandes ciudades, sin embargo se ha observado que durante los períodos epidémicos un serotipo determinado es predominante y desplaza casi totalmente el serotipo circulante en el período epidémico anterior. Se propone que la emergencia de la fiebre hemorrágica por dengue en Venezuela en 1989 está asociada a la introducción de virus dengue 2 genotipo Asiático, el cual es reconocido por ser más virulento y reemplazó el genotipo Caribe autóctono en las Américas.