Persistence and risk factors of high-risk human papillomavirus infection among HIV positive and HIV negative tanzanian women: a cohort study

Background

High-risk (HR) human papillomavirus (HPV) persistence is the most important risk factor for cervical cancer. We have assessed the type-specific HR HPV persistence among HIV positive and HIV negative Tanzanian women and factors associated with HR HPV persistence.

Methods

In a cohort study including 4080 Tanzanian women, 3074 attended follow-up examination (up to 32 months after enrollment). Cervical samples were obtained for liquid-based cytology and HPV DNA testing using Hybrid Capture 2 and Inno-Lipa Extra II. Information on lifestyle factors was collected through a personal interview. The probability of HR HPV persistence at a given time point since enrollment was estimated non-parametrically using the EMICM algorithm.

Results

Among the 462 women HR HPV positive at enrollment, 158 had at least one identical type detected at follow-up. The probability of persistence at 18 months after enrollment was 34.2 (95% CI 29.0–39.4). Stratifying by HIV status, the persistence probability was 42.9% (95% CI 33.5–51.9) among HIV positive, and 28.0% (95% CI 22.1–34.2) among HIV negative. Overall, HR HPV persistence was most common for HPV58, 35, 16, 31, and 52. Among HIV positive women it was HPV45, and HPV16, followed by HPV58 and HPV18, and among HIV negative women it was HPV31, HPV33 and HPV58. Risk factors associated with persistence of HR HPV were older age, longer interval between enrollment and follow-up, binge drinking, and HIV status.

Conclusions

HR HPV persistence was common in Tanzania, and most common among HIV positive women. Overall, persistence was most frequent for HPV 58, 35, 16, 31 and 52. The nonavalent HPV vaccine should be considered.

The association between human papillomavirus and cervical high-grade cytology among HIV-positive and HIV-negative Tanzanian women: A cross-sectional study

INTRODUCTION

Human papillomavirus (HPV) is the causative agent of precancerous lesions and cervical cancer, cervical cancer being the leading cause of deaths in Tanzanian women. Early detection and treatment of precancerous lesions are important in the prevention of cervical cancer cases.

MATERIAL AND METHODS

We conducted a cross-sectional study among 3390 Tanzanian women aged 25-60 years. Information on lifestyle habits was collected, and women underwent gynecological examination with collection of cervical cells for conventional cytological and HPV testing. Blood samples were tested for HIV. The association between cervical high-grade cytology (HGC) and potential risk factors was examined using multivariable logistic regression adjusting for age and high-risk HPV (HR-HPV).

RESULTS

The prevalence of HGC was 3.6% and of low-grade cytology was 8.3%. In women who were both HR-HPV-positive and HIV-positive, the prevalence of HGC was 28.3%. It increased by age and was 47% among women aged 50-60 years. Women, who had their sexual debut at age 9-15 years and 16-18 years, respectively, had 2.5 and 2.4 times increased odds of HGC compared with women whose sexual debut was at age 21 years and older. HIV-positive women had increased odds of HGC in comparison with HIV-negative women after adjustment for age (odds ratio [OR] 2.95, 95% CI 1.92-4.54). HR-HPV-positive women had nearly 100-fold increased odds of HGC compared with HR-HPV-negative women (OR 96.6, 95% CI 48.0-194), and this estimate was higher among HIV-positive women (OR 152.2, 95% CI 36.1-642.0).

CONCLUSIONS

Increasing age, early age at first intercourse, HR-HPV, and HIV infections were associated with a substantially increased risk of HGC.

Antidepressant use during pregnancy and risk of congenital heart defects: A case-time-control study

PURPOSE

We estimated the association between maternal antidepressant (AD) use in early pregnancy and risk of congenital heart defects.

METHODS

We applied a case-time-control design with the aim of controlling for confounding from time-invariant factors and compared the results of the design to results from a cohort design in a population of 792 685 singletons born alive in Denmark during 1995-2008. In the case-time-control design, we identified children diagnosed with a congenital heart defect in the first 5 years of life (cases) and compared maternal AD use in the risk period (the first 3 months of pregnancy) and the reference period (gestational months 5-7). A nondiseased control group was included to adjust for time trends of exposure. In the cohort design, we identified children whose mothers redeemed at least one AD prescription in the first 3 months of pregnancy (the exposed) and two other groups including the unexposed children with maternal AD prescriptions in the 12 months before pregnancy. We applied conditional logistic regression and logistic regression to compute odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

The case-time-control OR for any congenital heart defect was 1.03 (95% CI, 0.61-1.73), which was similar to the OR (1.09, 95% CI, 0.88-1.35) from the cohort design when we compared the exposed children with the unexposed children with maternal AD use before pregnancy.

CONCLUSIONS

The case-time-control design provided results similar to the cohort design when the cohort design had a better confounder control strategy. We discussed the strengths and drawbacks of case-time-control design.

Performance of careHPV, hybrid capture 2 and visual inspection with acetic acid for detection of high-grade cervical lesion in Tanzania: A cross-sectional study

Objective

To examine the test performance of careHPV, Hybrid Capture2 (HC2) and visual inspection with acetic acid (VIA) for detection of cytologically diagnosed high-grade cervical lesions or cancer (HSIL+).

Design

Cross-sectional study.

Setting

Ocean Road Cancer Institute (ORCI) and Kilimanjaro Christian Medical Center (KCMC), Tanzania.

Population

Women attending routine cervical cancer screening.

Method

We enrolled 4080 women (25–60 years) in the study. The women were interviewed on lifestyle habits, and tested for HIV. A cervical specimen for careHPV testing (performed at ORCI and KCMC), and a liquid-based cytology sample for HPV DNA detection using HC2 (performed at Tuebingen University Hospital, Germany) and for cytology assessment (performed at Vejle Hospital, Denmark) were obtained at a gynecological examination. Subsequently, VIA was performed. With cytology as gold standard, the sensitivity and specificity of careHPV, HC2, and VIA for detection of HSIL+ were calculated.

Results

Altogether, 23.6% had a positive careHPV test, 19.1% had positive HC2 test, and 6.3% had a positive VIA test. The sensitivity/specificity was 88.9%/78.9% for careHPV and 91.1%/83.7%, for HC2. VIA showed a low sensitivity of 31.1% but a high specificity (94.6%) for detection of HSIL+. The sensitivity of careHPV, HC2 and VIA was higher among younger women, and among HIV positive women. VIA triage of careHPV positive women improved specificity, but sensitivity dropped to 27%.

Conclusion

Our results confirm the low sensitivity of VIA for detection of HSIL+ and further document that careHPV test is promising as a primary screening method for cervical-cancer prevention in low-resource regions. A suitable triage test has to be identified.

[A therapeutic effect analysis of femur first principle and combined anteversion technique during total hip arthroplasty]

Objective: To investigate the situation of hip dislocation with the application of "femur first" principle and "combined anteversion technique" during total hip arthroplasty. Methods: A retrospective analysis has been done on the clinical data about 104 patients(133 hips)who were diagnosed as hip disease and were treated with total hip arthroplasty by the doctors from the Department of Joint Orthorpaedics of Shandong Provincial Hospital Affiliated to Shandong University from June 2014 to June 2016, and all the prostheses applied in the operation were cementless ones.Among them, 65 patients were males, 39 females and their age was 46.6 years (ranging from 23 to 76 years) .And 29 of them underwent bilateral hip operations and 75 unilateral ones.Seventy-six cases of aseptic necrosis of the femoral head in the terminal stage, 28 cases of hip dysplasia and osteoarthritis.Surgical approach: of all the operations, 103 hips were operated on with hardinge approach, 30 with posterolateral approach.During the operation, first of all, the femoral medullary cavity was broached and then the anteversion of intramedullary broacher was measured.After that, the anteversion of the acetabular cup was calculated as 37° minus the anteversion of the broacher, and the acetabular cup was implanted at that angle.The patients' prosthesis combined anteversion, range of motion of the hip joint, operation time, hemorrhage amount, and complications had been kept record.One, three, and six months respectively after the operation, all the patients received outpatient review, and took anteroposterior and lateral position X-ray examination.Harris hip score had been applied to evaluate their hip function before the operation and six months after the operation. Results: All the patients had been operated on smoothly, with the operation time of(57.6±14.5)minutes(36-115 minutes)and hemorrhage amount of (336.5±50.8)ml(180-620 ml). The operation finding showed that the combined anteversion by employing"femur first"principle and combined anteversion techniqueis was (36.6±6.8)°. Also, range of motion of the patients' hip conforms to the D'Lima criterion and no patients had experienced dislocation and some other serious complications.The follow-up ended at August 2017, which lasted for 12.2 months(6-18 months), and 88 cases(119 hips) were interviewed. The Harris hip score for the affected sides of the hip joints 6 months after the surgery was 94.6(86-100). Compared with the score of 29.8(12-43) before surgery, the t-test had proven its statistical significance(t=12.82, P=0.003). Conclusion: Based upon the "femoral first" principle and "combined anteversion technique" during total hip arthroplasty, these operations has been carried out well enough to meet the patients' needs of performing normal daily activities.

Parental Rheumatoid Arthritis and Autism Spectrum Disorders in Offspring: A Danish Nationwide Cohort Study

OBJECTIVE

Maternal rheumatoid arthritis (RA) has been associated with an increased risk of autism spectrum disorder (ASD) in the offspring. We assessed the potential influence of both maternal and paternal RA on the risk of ASD in offspring to disentangle the influence of genetic inheritance from other conditions potentially leading to fetal programming.

METHOD

The nationwide cohort study included all children born alive from 1977 to 2008 in Denmark (N = 1,917,723). Cox regression models were used to calculate hazard rate ratios (HR) of ASD in offspring exposed to maternal or paternal RA, compared to unexposed children.

RESULTS

Maternal RA was associated with an approximately 30% increased risk of ASD in the offspring (HR = 1.31 and 95% CI = 1.06-1.63). Also, paternal RA seemed to increase the risk of ASD by approximately 30% (HR = 1.33, 95% CI = 0.97-1.82).

CONCLUSION

Our findings suggest maternal as well as paternal RA to be associated with an increased risk of ASD in the offspring, indicating that genetic factors associated with RA may also play a role in the etiology of ASD in children of parents with RA.

Diode-pumped orthogonally polarized self-mode-locked Nd:YLF lasers subject to gain competition and thermal lensing effect

The stable condition for π-polarization emission in an a-cut Nd:YLF laser is numerical analyzed to find the critical pump power for generating the orthogonally polarized emission. With the numerical analysis, an orthogonally polarized SML lasers at wavelength of 1047 nm and 1053 nm is experimentally achieved in a simple concave-plano cavity without any additional optical element. It is experimentally observed that the polarization switching and coexistence was successfully demonstrated by introducing gain competition and anisotropic thermal lens effect. In the orthogonal polarization mode-locked operation, the pulse durations are found to be 19.1 and 18.8 ps for π- and σ-polarization with pulse repetition rates of 3.85 and 3.89 GHz, respectively.

Parental rheumatoid arthritis and childhood epilepsy: A nationwide cohort study

OBJECTIVE

To assess the influence of parental rheumatoid arthritis (RA) on risk of epilepsy.

METHODS

We performed a nationwide cohort study including all singletons born in Denmark from 1977 to 2008 (n = 1,917,723) through individual linkage to nationwide Danish registries. The children were followed for an average of 16 years. Main outcome measures were adjusted hazard ratios (HRs) for epilepsy with onset in early childhood (29 days-4 years), late childhood (5-15 years), adolescence/adulthood (≥15 years), and at any age until the end of follow-up (December 31, 2010).

RESULTS

Compared to unexposed children, children exposed to maternal RA had an increased risk of early and late childhood epilepsy (adjusted HRs 1.34 [95% confidence interval (CI) 1.13-1.60] and 1.26 [95% CI 1.13-1.41]), while children exposed to maternal RA had no increased risk of epilepsy in adolescence/adulthood (HR 1.15 [95% CI 0.92-1.45]). Paternal RA was not associated with an overall risk of epilepsy in the offspring (HR 0.96 [95% CI 0.81-1.15]) or at any age. Children exposed to maternal RA in utero had a more pronounced increased risk of early childhood epilepsy than children exposed to mothers who were diagnosed with RA after childbirth (HR 1.90 [95% CI 1.26-2.86] vs HR 1.26 [95% CI 1.03-1.52], respectively [p = 0.16]).

CONCLUSIONS

Exposure to maternal RA was associated with an increased risk of childhood epilepsy, while exposure to paternal RA was not, which indicates that changes in the intrauterine environment may play a role.

Maternal Antenatal Bereavement and Neural Tube Defect in Live-Born Offspring: A Cohort Study

Background

Maternal emotional stress during pregnancy has previously been associated with congenital neural malformations, but most studies are based on data collected retrospectively. The objective of our study was to investigate associations between antenatal maternal bereavement due to death of a close relative and neural tube defects (NTDs) in the offspring.

Methods

We performed a register-based cohort study including all live-born children (N = 1,734,190) from 1978–2008. Exposure was bereavement due to loss of a close relative from one year before conception to the end of the first trimester of pregnancy. The outcome was NTDs in the offspring according to the International Classification of Disease. We used multivariate logistic regression to estimate prevalence odds ratios (ORs).

Results

A total of 2% children were born to mothers who lost a close relative prenatally. During 30 years of follow-up, 1,115 children were diagnosed with any NTDs: spina bifida (n = 889), anencephaly (n = 85) and encephalocele (n = 164). And 23 children were diagnosed with two types of NTDs. Overall, when comparing bereaved mothers to non-bereaved mothers, no significant increased prevalence of NTDs in the offspring was seen (OR = 0.84; 95% confidence interval: 0.52–1.33).

Conclusion

Overall maternal bereavement in the antenatal period was not related to NTDs in liveborn offspring.

Comparison of two methods for RNA extraction from the nucleus pulposus of intervertebral discs

RNA extraction from the nucleus pulposus of intervertebral discs has been extensively used in orthopedic studies. We compared two methods for extracting RNA from the nucleus pulposus: liquid nitrogen grinding and enzyme digestion. The RNA was detected by agarose gel electrophoresis, and the purity was evaluated by absorbance ratio using a spectrophotometer. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) expression was assayed by reverse transcription-polymerase chain reaction (RT-PCR). Thirty human lumbar intervertebral discs were used in this study. The liquid nitrogen-grinding method was used for RNA extraction from 15 samples, and the mean RNA concentration was 491.04 ± 44.16 ng/mL. The enzyme digestion method was used on 15 samples, and the mean RNA concentration was 898.42 ± 38.64 ng/mL. The statistical analysis revealed that there was a significant difference in concentration between the different methods. Apparent 28S, 18S, and 5S bands were detectable in RNA extracted using the enzyme digestion method, whereas no 28S or 18S bands were detected in RNA extracted using the liquid nitrogen-grinding method. The GAPDH band was visible, and no non-specific band was detected in the RT-PCR assay by the enzyme digestion method. Therefore, the enzyme digestion method is an efficient and easy method for RNA extraction from the nucleus pulposus of intervertebral discs for further intervertebral disc degeneration-related studies.

Hypersingular meshless method using double-layer potentials for three-dimensional exterior acoustic problems

Three-dimensional exterior acoustic problems with irregular domains are solved using a hypersingular meshless method. In particular, the method of fundamental solutions (MFS) is used to formulate and analyze such acoustic problems. It is well known that source points for MFS cannot be located on the real boundary due to the singularity of the kernel functions. Thus, the diagonal terms of the influence matrices are unobtainable when source points are located on the boundary. An efficient approach is proposed to overcome such difficulties, when the MFS is used for three-dimensional exterior acoustic problems. This work is an extension of previous research on two-dimensional problems. The solution of the problem is expressed in terms of a double-layer potential representation on the physical boundary. Three examples are presented in which the proposed method is compared to the MFS and boundary element method. Good numerical performance is demonstrated by the proposed hypersingular meshless method.

Parental rheumatoid arthritis and long-term child morbidity: a nationwide cohort study

OBJECTIVE

To estimate the influence of parental rheumatoid arthritis (RA) on child morbidity.

DESIGN

Nationwide cohort study.

SETTING

Individual linkage to nationwide Danish registries.

PARTICIPANTS

All singletons born in Denmark during 1977-2008 (n=1 917 723) were followed for an average of 16 years.

MAIN OUTCOME MEASURES

Adjusted HRs for child morbidity; that is, 11 main diagnostic groups and specific autoimmune diseases within the International Classification of Diseases 8th and 10th versions.

RESULTS

Compared with unexposed children, children exposed to maternal RA ('clinical' and 'preclinical') (n=13 566) had up to 26% higher morbidity in 8 of 11 main diagnostic groups. Similar tendencies were found in children exposed to paternal RA ('clinical' and 'preclinical') (n=6330), with statistically significantly higher morbidity in 6 of 11 diagnostic groups. HRs were highest for autoimmune diseases with up to three times increased risk of juvenile idiopathic arthritis (HR, 95% CI 3.30, 2.71 to 4.03 and 2.97, 2.20 to 4.01) and increased risk of up to 40% of diabetes mellitus type 1 (HR, 95% CI 1.37, 1.12 to 1.66 and 1.44, 1.09 to 1.90) and up to 30% increased HR of asthma (HR, 95% CI 1.28, 1.20 to 1.36 and 1.15, 1.04 to 1.26). Conclusions were roughly similar for children exposed to maternal clinical RA and for children only followed up to 16 years of age.

CONCLUSION

Children of parents with RA had consistent excess morbidity. If the associations reflect biological mechanisms, genetic factors seem to play an important role. These findings call for attention given to children of parents with RA.

Trends in All-Cause Mortality across Gestational Age in Days for Children Born at Term

Background

Term birth is a gestational age from 259 days to 293 days. However trends in mortality according to gestational ages in days have not yet been described in this time period.

Methods and Findings

Based on nation-wide registries, we conducted a population-based cohort study among all children born at term in Denmark from 1997 to 2004 to estimate differences in mortality across gestational ages in days among singletons born at term. We studied early-neonatal mortality, neonatal mortality, infant mortality, and five-year mortality. Children were followed from birth up to the last day of the defined mortality period or December 31, 2009. A total of 360,375 singletons born between 259 and 293 days of gestation were included in the study. Mortality decreased with increasing gestational age in days and the highest mortality was observed among children born at 37 week of gestation. A similar pattern was observed when analyses were restricted to children born to by mothers without pregnancy complications.

Conclusions

This study demonstrates heterogeneity in mortality rates even among singletons born at term. The highest mortality was observed among children born 37 weeks of gestation, which call for cautions when inducing labor in term pregnancies just reaching 37 weeks of gestation. The findings support that 37 weeks of gestation should be defined as early term.

Comparison of amoxicillin + clavulanate with or without intranasal fluticasone for the treatment of uncomplicated acute rhinosinusitis in children

AIM

Intranasal corticosteroids (INS) have been proven effective in controlling postnasal drip, decreasing inflammatory response, reducing nasal swelling, and increasing aeration of the sinuses such that INS are recommended as treatment of sinusitis.

METHODS

Fifty children with acute rhinosinusitis, 50 children with acute rhiniosinusitis and allergic rhinitis (AR), and 20 rhiniosinusitis children as control were selected for investigation. Each group had a single-blind treatment of three types: with coamoxiclav only, with coamoxiclav plus INS, and with matched placebo (without antibiotics and INS) for two weeks. Nasal symptoms were then evaluated. The outcome was measured by using major symptom score (MSS) after treatment for 14 days.

RESULTS

Therapeutic effectiveness was 92% in rhinosinusitis patients treated with co-amoxiclav and 84% in those treated with co-amoxiclav plus INS. Among patients with sinusitis combined with AR, therapeutic efficacy was 88% for those treated with co-amoxiclav and 96% for those treated with co-amoxiclav plus INS. Only 30% of the symptoms were reduced in the placebo group.

CONCLUSION

There are no statistical differences in the acute sinusitis group treated with co-amoxiclav with or without INS. In the sinusitis with AR group, the efficacy of co-amoxiclav with INS is higher than in children treated with co-amoxiclav alone.

Mapping forested wetlands in the Great Zhan River Basin through integrating optical, radar, and topographical data classification techniques

Knowledge of the spatial extent of forested wetlands is essential to many studies including wetland functioning assessment, greenhouse gas flux estimation, and wildlife suitable habitat identification. For discriminating forested wetlands from their adjacent land cover types, researchers have resorted to image analysis techniques applied to numerous remotely sensed data. While with some success, there is still no consensus on the optimal approaches for mapping forested wetlands. To address this problem, we examined two machine learning approaches, random forest (RF) and K-nearest neighbor (KNN) algorithms, and applied these two approaches to the framework of pixel-based and object-based classifications. The RF and KNN algorithms were constructed using predictors derived from Landsat 8 imagery, Radarsat-2 advanced synthetic aperture radar (SAR), and topographical indices. The results show that the objected-based classifications performed better than per-pixel classifications using the same algorithm (RF) in terms of overall accuracy and the difference of their kappa coefficients are statistically significant (p<0.01). There were noticeably omissions for forested and herbaceous wetlands based on the per-pixel classifications using the RF algorithm. As for the object-based image analysis, there were also statistically significant differences (p<0.01) of Kappa coefficient between results performed based on RF and KNN algorithms. The object-based classification using RF provided a more visually adequate distribution of interested land cover types, while the object classifications based on the KNN algorithm showed noticeably commissions for forested wetlands and omissions for agriculture land. This research proves that the object-based classification with RF using optical, radar, and topographical data improved the mapping accuracy of land covers and provided a feasible approach to discriminate the forested wetlands from the other land cover types in forestry area.

Cancer Mortality in People Treated with Antidepressants before Cancer Diagnosis: A Population Based Cohort Study

Background

Depression is common after a cancer diagnosis and is associated with an increased mortality, but it is unclear whether depression occurring before the cancer diagnosis affects cancer mortality. We aimed to study cancer mortality of people treated with antidepressants before cancer diagnosis.

Methods and Findings

We conducted a population based cohort study of all adults diagnosed with cancer between January 2003 and December 2010 in Denmark (N = 201,662). We obtained information on cancer from the Danish Cancer Registry, on the day of death from the Danish Civil Registry, and on redeemed antidepressants from the Danish National Prescription Registry. Current users of antidepressants were defined as those who redeemed the latest prescription of antidepressant 0–4 months before cancer diagnosis (irrespective of earlier prescriptions), and former users as those who redeemed the latest prescription five or more months before cancer diagnosis. We estimated an all-cause one-year mortality rate ratio (MRR) and a conditional five-year MRR for patients who survived the first year after cancer diagnosis and confidence interval (CI) using a Cox proportional hazards regression model. Overall, 33,111 (16.4%) patients redeemed at least one antidepressant prescription in the three years before cancer diagnosis of whom 21,851 (10.8%) were current users at the time of cancer diagnosis. Current antidepressant users had a 32% higher one-year mortality (MRR = 1.32, 95% CI: 1.29–1.35) and a 22% higher conditional five-year mortality (MRR = 1.22, 95% CI: 1.17–1.26) if patients survived the first year after the cancer diagnosis than patients not redeeming antidepressants. The one-year mortality was particularly high for patients who initiated antidepressant treatment within four months before cancer diagnosis (MRR = 1.54, 95% CI: 1.47–1.61). Former users had no increased cancer mortality.

Conclusions

Initiation of antidepressive treatment prior to cancer diagnosis is common and is associated with an increased mortality.

Decline of Yangtze River water and sediment discharge: Impact from natural and anthropogenic changes

The increasing impact of both climatic change and human activities on global river systems necessitates an increasing need to identify and quantify the various drivers and their impacts on fluvial water and sediment discharge. Here we show that mean Yangtze River water discharge of the first decade after the closing of the Three Gorges Dam (TGD) (2003–2012) was 67 km³/yr (7%) lower than that of the previous 50 years (1950–2002), and 126 km³/yr less compared to the relatively wet period of pre-TGD decade (1993–2002). Most (60–70%) of the decline can be attributed to decreased precipitation, the remainder resulting from construction of reservoirs, improved water-soil conservation and increased water consumption. Mean sediment flux decreased by 71% between 1950–1968 and the post-TGD decade, about half of which occurred prior to the pre-TGD decade. Approximately 30% of the total decline and 65% of the decline since 2003 can be attributed to the TGD, 5% and 14% of these declines to precipitation change, and the remaining to other dams and soil conservation within the drainage basin. These findings highlight the degree to which changes in riverine water and sediment discharge can be related with multiple environmental and anthropogenic factors.

Maternal preeclampsia and childhood asthma in the offspring

BACKGROUND

Preeclampsia is a possible risk factor for childhood asthma in the offspring. Our aim was to find whether preeclampsia is associated with childhood asthma. We also aimed to study whether a possible association can be explained by factors shared by siblings.

METHODS

All eligible live singletons born in Denmark during 1993-2007 were identified (N = 923,533), and the occurrence of preeclampsia during the index pregnancy was determined. The children were followed from their 3rd birthday to the first hospitalization, outpatient contact or prescription for asthma, emigration, death, their 18th birthday, or the end of 2010, whichever came first. We carried out a nested case-control and a case-sibling study with density sampling to estimate incidence rate ratio (IRR) of asthma as a function of maternal preeclampsia, using conditional logistic regression.

RESULTS

A total of 115,522 asthma cases were identified during 1996-2010. In the case-control analysis, the overall IRR of asthma for those exposed to maternal preeclampsia was 1.19 (95% confidence interval (CI): 1.15, 1.24). The IRRs for asthma according to early and late onset preeclampsia were 1.88 (95% CI: 1.67, 2.11) and 1.14 (95% CI: 1.10, 1.19). In the case-sibling analysis, the corresponding IRRs were 1.06 (95% CI: 0.98, 1.14), 1.15 (95% CI: 1.02, 1.29), and 1.02 (95% CI: 0.93, 1.11), respectively.

CONCLUSIONS

Early onset preeclampsia was associated with an increased risk of asthma in the offspring, but part of this association may be due to confounding by factors shared by siblings.

Medical augmentation of labor and the risk of ADHD in offspring: a population-based study

BACKGROUND AND OBJECTIVE

Oxytocin for labor augmentation is widely used in obstetric care in Western countries. Two recent, smaller studies found opposing results regarding the association between prenatal exposure to oxytocin for labor augmentation and attention-deficit/hyperactivity disorder (ADHD). In Denmark, oxytocin is the medication used for nearly all medical augmentations of labor, and we examined the association between medical augmentation of labor and ADHD in a large cohort study based on national register data.

METHODS

All singletons born after spontaneous onset of labor in Denmark between 2000 and 2008 (N = 546 146) were included in the study. Data from the Danish Medical Birth Registry on medical augmentation of labor (yes/no) were used to identify exposed children. ADHD was defined based on the diagnostic codes of International Classification of Diseases, 10th Revision, for hyperkinetic disorder and information on dispensed ADHD medication. A multivariate proportional hazards regression model was used to test the association.

RESULTS

Among 546 146 deliveries, 26% included medical augmentation of labor, and 0.9% of the children were identified as having ADHD (n = 4617). We found no association between augmentation of labor and ADHD in the offspring (hazard ratio: 1.05 [95% confidence interval: 0.98-1.13]).

CONCLUSIONS

Our study does not support an association between medical augmentation of labor and ADHD in the child.

Severity of birth defects after propylthiouracil exposure in early pregnancy

BACKGROUND

Propylthiouracil (PTU) used in the treatment of maternal hyperthyroidism in early pregnancy may be associated with a higher prevalence of birth defects in the face and neck region and in the urinary system but the severity of these complications remains to be elucidated.

METHODS

Review of hospital-registered cases of birth defects in the face and neck region and in the urinary system after PTU exposure in early pregnancy. We obtained information on maternal redeemed prescription of PTU and child diagnosis of birth defect from nationwide registers for all children born in Denmark between 1996 and 2008 (n=817,093). The children were followed until December 31, 2010 (median age, 8.3 years) and the Cox proportional hazards model was used to estimate adjusted hazard ratio (HR) with 95% confidence interval (CI) for having a birth defect after PTU exposure versus nonexposed children (n=811,730).

RESULTS

Fourteen cases of birth defects were identified in the face and neck region and in the urinary system after PTU exposure in early pregnancy; 11 children were exposed to PTU only (n=564), whereas 3 children were born to mothers who switched from methimazole (MMI)/carbimazole (CMZ) to PTU in early pregnancy (n=159). Among children exposed to PTU only, the adjusted HR for having a birth defect in the face and neck region was 4.92 (95% CI 2.04-11.86) and in the urinary system 2.73 (1.22-6.07). Looking into details of the 14 cases, 7 children were diagnosed with a birth defect in the face and neck region (preauricular and branchial sinus/fistula/cyst) and 7 children had a birth defect in the urinary system (single cyst of kidney and hydronephrosis). Surgical treatment was registered in 6 of the cases with a birth defect in the face and neck region and 3 of the cases with a birth defect in the urinary system. Two of the children with a birth defect in the urinary system also had other birth defects (genital organs).

CONCLUSIONS

We report details on possible PTU-associated birth defects. They tend to be less severe than the defects observed after MMI/CMZ exposure. Yet, the majority of affected children had to undergo surgery.

Spontaneous abortion, stillbirth and hyperthyroidism: a danish population-based study

OBJECTIVES

Pregnancy loss in women suffering from hyperthyroidism has been described in case reports, but the risk of pregnancy loss caused by maternal hyperthyroidism in a population is unknown. We aimed to evaluate the association between maternal hyperthyroidism and pregnancy loss in a population-based cohort study.

STUDY DESIGN

All pregnancies in Denmark from 1997 to 2008 leading to hospital visits (n = 1,062,862) were identified in nationwide registers together with information on maternal hyperthyroidism for up to 2 years after the pregnancy [hospital diagnosis/prescription of antithyroid drug (ATD)]. The Cox proportional hazards model was used to estimate adjusted hazard ratio (aHR) with 95% confidence interval (CI) for spontaneous abortion (gestational age <22 weeks) and stillbirth (≥22 weeks), reference: no maternal thyroid dysfunction.

RESULTS

When maternal hyperthyroidism was diagnosed before/during the pregnancy (n = 5,229), spontaneous abortion occurred more often both in women treated before the pregnancy alone [aHR 1.28 (95% CI 1.18-1.40)] and in women treated with ATD in early pregnancy [1.18 (1.07-1.31)]. When maternal hyperthyroidism was diagnosed and treated for the first time in the 2-year period after the pregnancy (n = 2,361), there was a high risk that the pregnancy under study had terminated with a stillbirth [2.12 (1.30-3.47)].

CONCLUSIONS

Both early (spontaneous abortion) and late (stillbirth) pregnancy loss were more common in women suffering from hyperthyroidism. Inadequately treated hyperthyroidism in early pregnancy may have been involved in spontaneous abortion, and undetected high maternal thyroid hormone levels present in late pregnancy may have attributed to an increased risk of stillbirth.

Trimethoprim use before pregnancy and risk of congenital malformation: reanalyzed using a case-crossover design and a case-time-control design

PURPOSE

Studies on the safety of drugs used during pregnancy are necessary and important but prone to bias. Using cases as their own controls can reduce bias. We used a case-crossover design and a case-time-control design to estimate the risk of congenital malformation (CM) for children born to mothers who redeemed a trimethoprim prescription shortly before pregnancy.

METHODS

The study was based on all live born singletons (N = 685 600) in Denmark whose mothers had available information on prescriptions in the Danish National Prescription Registry between 1996 and 2008. We defined 1-3 months before pregnancy as a potential risk period and 13-15 months before pregnancy as a reference period. Two other reference periods were used (7-9 months before pregnancy and months 4-6 of pregnancy). The case-crossover design is dependent on the assumption of a stable trimethoprim prescription over the study period in the source population. To estimate the trend of trimethoprim prescriptions, we used a control group comprising children without CMs.

RESULTS

Both study designs showed children had a higher risk of overall CM [odds ratio of 1.66, 95% confidence interval (CI): 1.10-2.53 and 1.50, 95%CI: 0.66-3.38, respectively] if their mothers had a trimethoprim prescription in the 3 months before pregnancy and subtypes of CM for example in the musculoskeletal system, which were consistent to the previous findings from a cohort study.

CONCLUSIONS

This study corroborates that trimethoprim is a potential teratogen when used 3 months before pregnancy and demonstrates the value of case-only approaches for studying, for example, adverse effects of antibiotics in reproductive epidemiology.

Psychiatric disease in late adolescence and young adulthood. Foetal programming by maternal hypothyroidism?

OBJECTIVE

Lack of maternal thyroid hormones during foetal brain development may lead to structural abnormalities in the brain. We hypothesized that maternal hypothyroidism during the pregnancy could programme the foetus to development of psychiatric disease later in life.

DESIGN

Danish nationwide register study.

PARTICIPANTS

Singletons live-born 1980-1990.

MEASUREMENTS

Cox proportional hazards model was used to estimate adjusted hazard ratio (aHR) with 95% confidence interval for offspring redemption of ≥2 prescriptions of a psychiatric drug from age 15 to 31 years.

RESULTS

Among 542 100 adolescents and young adults included, altogether 3979 (0·7%) were born to mothers with hypothyroidism registered before 1996. In crude analyses, the use of a psychiatric drug was more frequent in late adolescence and young adulthood when the mother had hypothyroidism (P < 0·001); however, several possible confounders had to be taken into account. For example, mothers with hypothyroidism often also had a psychiatric registration (38·5% vs 27·7%, P < 0·001) and the use of psychiatric drugs changed over time. After adjustment for confounders including birth year, maternal age and maternal psychiatric history, maternal hypothyroidism was associated with an increased risk of having redeemed prescriptions of anxiolytics [aHR 1·23 (1·03-1·48)] and antipsychotics [aHR 1·22 (1·03-1·44)] in late adolescence and young adulthood. For antidepressants, aHR was 1·07 (0·98-1·17).

CONCLUSIONS

The association between maternal hypothyroidism and the use of a psychiatric drug in late adolescence and young adulthood was partly confounded by maternal psychiatric history, but foetal programming by maternal hypothyroidism may be part of the mechanisms leading to the use of anxiolytics and antipsychotics.

Development of KMnO(4)-releasing composites for in situ chemical oxidation of TCE-contaminated groundwater

The objective of this study was to develop a controlled-oxidant-release technology combining in situ chemical oxidation (ISCO) and permeable reactive barrier (PRB) concepts to remediate trichloroethene (TCE)-contaminated groundwater. In this study, a potassium permanganate (KMnO4)-releasing composite (PRC) was designed for KMnO4 release. The components of this PRC included polycaprolactone (PCL), KMnO4, and starch with a weight ratio of 1.14:2:0.96. Approximately 64% (w/w) of the KMnO4 was released from the PRC after 76 days of operation in a batch system. The results indicate that the released KMnO4 could oxidize TCE effectively. The results from a column study show that the KMnO4 released from 200 g of PRC could effectively remediate 101 pore volumes (PV) of TCE-contaminated groundwater (initial TCE concentration = 0.5 mg/L) and achieve up to 95% TCE removal. The effectiveness of the PRC system was verified by the following characteristics of the effluents collected after the PRC columns (barrier): (1) decreased TCE concentrations, (2) increased ORP and pH values, and (3) increased MnO2 and KMnO4 concentrations. The results of environmental scanning electron microscope (ESEM) analysis show that the PCL and starch completely filled up the pore spaces of the PRC, creating a composite with low porosity. Secondary micro-scale capillary permeability causes the KMnO4 release, mainly through a reaction-diffusion mechanism. The PRC developed could be used as an ISCO-based passive barrier system for plume control, and it has the potential to become a cost-effective alternative for the remediation of chlorinated solvent-contaminated groundwater.

Attention deficit hyperactivity disorder and autism spectrum disorder in children born to mothers with thyroid dysfunction: a Danish nationwide cohort study

OBJECTIVE

To examine the association between maternal hyper- and hypothyroidism and the risk of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in the child.

DESIGN

A population-based cohort study.

SETTING

Singletons liveborn in Denmark between 1991 and 2004.

POPULATION

A total of 857 014 singletons alive and living in Denmark at the age of 3 years.

METHODS

Information on the diagnosis and/or treatment of maternal thyroid disease and the neurodevelopmental disorders ADHD and ASD in the child was obtained from Danish nationwide registers. The Cox proportional hazards model was used to estimate the hazard ratio (HR) with 95% confidence interval (95% CI) for risk of ADHD and ASD in children born to mothers with thyroid dysfunction, adjusting for potential confounding factors.

MAIN OUTCOME MEASURES

ADHD and ASD in the child.

RESULTS

Altogether, 30,295 singletons (3.5%) were born to mothers with thyroid dysfunction. Maternal hyperthyroidism diagnosed and treated for the first time after the birth of the child increased the risk of ADHD in the child (adjusted HR 1.23; 95% CI 1.05-1.44), whereas hypothyroidism increased the risk of ASD (adjusted HR 1.34; 95% CI 1.14-1.59). No significant association was seen for maternal diagnosis and treatment prior to the birth of the child.

CONCLUSIONS

Children born to mothers diagnosed and treated for the first time for thyroid dysfunction after their birth may have been exposed to abnormal levels of maternal thyroid hormone already present during the pregnancy, and this untreated condition could increase the risk of specific neurodevelopmental disorders in the child.

Smoking reduces the risk of hypothyroidism and increases the risk of hyperthyroidism: evidence from 450,842 mothers giving birth in Denmark

OBJECTIVE

Smoking may influence on the occurrence of thyroid disease, but studies have led to inconsistent results. In Denmark, information on maternal smoking during pregnancy is registered by midwives, and we investigated the association between maternal smoking as reported during pregnancy and the subsequent maternal risk of having hyper- or hypothyroidism diagnosed.

DESIGN

Population-based cohort study.

PARTICIPANTS

Using Danish nationwide registers, we identified mothers giving birth in Denmark, 1996-2008, and studied their first pregnancy in the study period.

MEASUREMENTS

Information on maternal smoking during the pregnancy and maternal diagnosis of hyper- or hypothyroidism was obtained from the Danish National Hospital Register (DNHR) and prescription of thyroid medication from the Danish National Prescription Register (DNPR). Cox proportional hazards model was used to estimate hazard ratio (HR) with 95% confidence interval (95% CI) for onset of maternal hyper- or hypothyroidism after birth of the child in multivariate analyses adjusting for potential confounders.

RESULTS

Among mothers included (n = 450 842), altogether 89,022 (19·7%) reported that they were smokers during the first pregnancy in the study period, and 8905 (2·0%) developed hyper (n = 3389)- or hypothyroidism (n = 5516) after birth of the child. Maternal smoking was associated with a subsequent decreased risk of developing hypothyroidism (adjusted HR 0·75 (95% CI 0·70-0·81)) and an increased risk of hyperthyroidism (1·38 (1·27-1·49)).

CONCLUSIONS

Danish nationwide registration of maternal smoking during pregnancy adds further evidence to an association between smoking and thyroid dysfunction; smoking reduced the risk of hypothyroidism and increased the risk of hyperthyroidism.

Antenatal hypnosis training and childbirth experience: a randomized controlled trial

BACKGROUND

Childbirth is a demanding event in a woman's life. The aim of this study was to explore whether a brief intervention in the form of an antenatal course in self-hypnosis to ease childbirth could improve the childbirth experience.

METHOD

In a randomized, controlled, single-blinded trial, 1,222 healthy nulliparous women were allocated to one of three groups during pregnancy: A hypnosis group participating in three 1-hour sessions teaching self-hypnosis to ease childbirth, a relaxation group receiving three 1-hour lessons in various relaxation methods and Mindfulness, and a usual care group receiving ordinary antenatal care only. Wijmas Delivery Expectancy/Experience Questionnaire (W-DEQ) was used to measure the childbirth experience 6 weeks postpartum.

RESULTS

The intention-to-treat analysis indicated that women in the hypnosis group experienced their childbirth as better compared with the other two groups (mean W-DEQ score of 42.9 in the Hypnosis group, 47.2 in the Relaxation group, and 47.5 in the Care as usual group (p = 0.01)). The tendency toward a better childbirth experience in the hypnosis group was also seen in subgroup analyses for mode of delivery and for levels of fear.

CONCLUSION

In this large randomized controlled trial, a brief course in self-hypnosis improved the women's childbirth experience.

Birth defects after early pregnancy use of antithyroid drugs: a Danish nationwide study

INTRODUCTION

Hyperthyroidism in pregnant women should be adequately treated to prevent maternal and fetal complications, but teratogenic effects of antithyroid drug (ATD) treatment have been described. Evidence is still lacking in regard to the safety and choice of ATD in early pregnancy.

OBJECTIVE

Our objective was to determine to which degree the use of methimazole (MMI)/carbimazole (CMZ) and propylthiouracil (PTU) in early pregnancy is associated with an increased prevalence of birth defects.

METHODS

This Danish nationwide register-based cohort study included 817 093 children live-born from 1996 to 2008. Exposure groups were assigned according to maternal ATD use in early pregnancy: PTU (n = 564); MMI/CMZ (n = 1097); MMI/CMZ and PTU (shifted in early pregnancy [n = 159]); no ATD (ATD use, but not in pregnancy [n = 3543]); and nonexposed (never ATD use [n = 811 730]). Multivariate logistic regression was used to estimate adjusted odds ratio (OR) with 95% confidence interval (95% CI) for diagnosis of a birth defect before 2 years of age in exposed versus nonexposed children.

RESULTS

The prevalence of birth defects was high in children exposed to ATD in early pregnancy (PTU, 8.0%; MMI/CMZ, 9.1%; MMI/CMZ and PTU, 10.1%; no ATD, 5.4%; nonexposed, 5.7%; P < .001). Both maternal use of MMI/CMZ (adjusted OR = 1.66 [95% CI 1.35-2.04]) and PTU (1.41 [1.03-1.92]) and maternal shift between MMI/CMZ and PTU in early pregnancy (1.82 [1.08-3.07]) were associated with an increased OR of birth defects. MMI/CMZ and PTU were associated with urinary system malformation, and PTU with malformations in the face and neck region. Choanal atresia, esophageal atresia, omphalocele, omphalomesenteric duct anomalies, and aplasia cutis were common in MMI/CMZ-exposed children (combined, adjusted OR = 21.8 [13.4-35.4]).

CONCLUSIONS

Both MMI/CMZ and PTU were associated with birth defects, but the spectrum of malformations differed. More studies are needed to corroborate results in regard to early pregnancy shift from MMI/CMZ to PTU. New ATD with fewer side effects should be developed.

Low Birth Weight in Children Born to Mothers with Hyperthyroidism and High Birth Weight in Hypothyroidism, whereas Preterm Birth Is Common in Both Conditions: A Danish National Hospital Register Study

OBJECTIVES

Maternal hyper- and hypothyroidism have been associated with increased risk of adverse pregnancy outcomes, but studies have led to inconsistent results. We aimed to identify children born to mothers with a hospital-recorded diagnosis of thyroid dysfunction in Denmark and to study the association with gestational age at delivery and birth weight of the child.

STUDY DESIGN

Population-based cohort study using Danish nationwide registers. All singleton live births in Denmark between January 1, 1978 and December 31, 2006 were identified and stratified by maternal diagnosis of hyper- or hypothyroidism registered in the Danish National Hospital Register before January 1, 2007.

RESULTS

Maternal first-time diagnosis of thyroid dysfunction before, during or after pregnancy was registered in 32,809 (2.0%) of the singleton live births (n = 1,638,338). Maternal diagnosis of hyperthyroidism (adjusted OR 1.22, 95% CI 1.15-1.30) and hypothyroidism (adjusted OR 1.17, 95% CI 1.08-1.27) were associated with increased risk of preterm birth. Moreover, birth weight in children born to mothers with a diagnosis of hyperthyroidism was lower (adjusted difference -51 g, 95% CI -58 to -43 g) and higher in relation to maternal hypothyroidism (adjusted difference 20 g, 95% CI 10-30 g). Hyperthyroidism was associated with small-for-gestational-age (adjusted OR 1.15, 95% CI 1.10-1.20) and hypothyroidism with large-for-gestational-age children (adjusted OR 1.24, 95% CI 1.17-1.31).

CONCLUSIONS

Based on Danish nationwide registers, both maternal hyper- and hypothyroidism were associated with increased risk of preterm birth. Actual birth weight of the child and birth weight for gestational age were low if the mother had a diagnosis of hyperthyroidism and high if the diagnosis was hypothyroidism.

Incidence and risk of central nervous system metastases as site of first recurrence in patients with HER2-positive breast cancer treated with adjuvant trastuzumab

BACKGROUND

Central nervous system (CNS) disease as the site of first relapse after exposure to adjuvant trastuzumab has been reported. We carried out comprehensive meta-analysis to determine the risk of CNS metastases as the first site of recurrence in patients with HER2-positive breast cancer who received adjuvant trastuzumab.

METHODS

Eligible studies include randomized trials of adjuvant trastuzumab administered for 1 year to patients with HER2-positive breast cancer who reported CNS metastases as first site of disease recurrence. Statistical analyses were conducted to calculate the incidence, relative risk (RR), and 95% confidence intervals (CIs) using fixed-effects inverse variance and random-effects models.

RESULTS

A total of 9020 patients were included. The incidence of CNS metastases as first site of disease recurrence in HER2-positive patients receiving adjuvant trastuzumab was 2.56% (95% CI 2.07% to 3.01%) compared with 1.94% (95% CI 1.54% to 2.38%) in HER2-positive patients who did not receive adjuvant trastuzumab. The RR of the CNS as first site of relapse in trastuzumab-treated patients was 1.35 (95% CI 1.02-1.78, P = 0.038) compared with control arms without trastuzumab therapy. The ratio of CNS metastases to total number of recurrence events was 16.94% (95% CI 10.85% to 24.07%) and 8.33% (95% CI 6.49% to 10.86%) for the trastuzumab-treated and control groups, respectively. No statistically significant differences were found based on trastuzumab schedule or median follow-up time. No evidence of publication bias was observed.

CONCLUSIONS

Adjuvant trastuzumab is associated with a significant increased risk of CNS metastases as the site of first recurrence in HER2-positive breast cancer patients.

Magnetic field enhanced resonant tunneling in a silicon nanowire single-electron-transistor

We report fabrication, measurement and simulation of silicon single-electron-transistors made on silicon-on-insulator wafers. At T-2 K, these devices showed clear Coulomb blockade structures. An external perpendicular magnetic field was found to enhance the resonant tunneling peak and was used to predict the presence of two laterally coupled quantum dots in the narrow constriction between the source-drain electrodes. The proposed model and measured experimental data were consistently explained using numerical simulations.

Early or recurrent preterm birth and maternal cardiovascular disease risk

PURPOSE

Preterm birth (PTB) has been associated with a later increased risk of maternal cardiovascular disease (CVD). We hypothesized a more pronounced relation between early or recurrent PTB and maternal CVD risk.

METHODS

We related PTB severity (earlier gestational age at delivery) and recurrence (>/=2) among women with births from 1973-1983 in Denmark (n = 427,765) to maternal CVD morbidity or mortality (1977-2006). Birth data were linked to CVD hospitalizations and deaths identified in national registers and data were analyzed using Cox proportional hazards models.

RESULTS

Women with a prior PTB had excess CVD after adjustment for age, parity, and education (hazard ratio [HR] = 1.36 [95% confidence interval (CI): 1.31, 1.41]). This was only modestly attenuated when women with preeclampsia or small for gestational age births were excluded, and the relationship was stronger for CVD mortality (HR = 1.98 [1.73, 2.26]). Recurrent PTB was associated with higher CVD morbidity compared to women with one PTB, particularly for ischemic events (HR = 1.78 [1.40, 2.27] vs. 1.22 [1.09, 1.36]). Risk was similarly elevated among women with early, moderate, and late PTB. Sensitivity analysis suggested that confounding by smoking only partly explained these associations.

CONCLUSIONS

Women with PTB, especially recurrent PTB, were at increased risk for CVD, suggesting common causes of these conditions.

Genetic polymorphism in milk fat globule-EGF factor 8 (MFG-E8) is associated with systemic lupus erythematosus in human

Milk fat globule-EGF factor 8 (MFG-E8) is a molecule implicated in phagocytic clearance of apoptotic cells by bridging between macrophages and apoptotic cells. Defects in MFG-E8 cause lupus-like disease in murine models. The aim of our study is to determine whether genetic variation in MFG-E8 predisposes human to systemic lupus erythematosus (SLE). A case-control study of MFG-E8 genetic polymorphism was performed on 147 SLE patients and 146 non-lupus control subjects. Single nucleotide polymorphisms (SNPs) in the coding sequence of human MFG-E8 gene were investigated. SNPs on MFG-E8 residues 3 (3(Arg or Ser)) and 76 (76(Leu or Met)) did not show genetic linkage. Genetic polymorphism on MFG-E8 residue 76 correlated significantly to SLE. The MFG-E8-76(Met) allele predisposed subjects to SLE in a recessive mode (odds ratio: 2.1, P = 0.020), while carriage of MFG-E8-76(Leu) were negatively associated with SLE. The MFG-E8 genotypic combinations with 3(Ser) and 76(Leu) showed the most pronounced protective effect on SLE when compared to the most predisposing genotype 3(Arg/Arg)-76(Met/Met) (OR: 0.29, P = 0.007). According to our result, MFG-E8 is associated with SLE predisposition in Taiwanese. Our study implicates that the impairment of phagocytic clearance of apoptotic cells through phosphotidylserine-dependent MFG-E8 system may lead to the development of human SLE.

Nonlinear saturation of cyclotron maser instability associated with energetic ring-beam electrons

We study the cyclotron maser instability (CMI) driven by an energetic ring-beam distribution by a particle simulation to explain possible generation mechanisms of intense radiation phenomena observed in space. The main objective is to understand the nonlinear processes that control saturation of the emission process. Our study reveals new issues that have been overlooked in past literature. It is found that electrostatic wave modes excited by the electron beam instability compete with the electromagnetic waves excited by the CMI. Nonlinear effects of these electrostatic modes tend to redistribute the energy of the energetic electrons and make the physics more complicated. The CMI can be much less effective in a realistic case than it is anticipated theoretically.

Preeclampsia and risk for epilepsy in offspring

OBJECTIVE

Eclampsia has been found to be a strong risk factor for epilepsy in the offspring, but it is unclear whether the risk also applies to the preceding condition, preeclampsia.

METHODS

We conducted a population-based cohort study of 1537860 singletons born in Denmark (1978-2004). Information on preeclampsia (mild, severe, and unspecified), eclampsia, and epilepsy was obtained from the Danish National Hospital Register. Information on gestational age, birth weight, and Apgar score was obtained from the Danish Medical Birth Registry. We used Cox proportional hazard models to estimate the incidence rate ratio of epilepsy for children who were exposed to preeclampsia or eclampsia in prenatal life.

RESULTS

We identified 45288 (2.9%) children who were exposed to preeclampsia (34823 to mild, 7043 to severe, and 3422 to unspecified preeclampsia) and 654 (0.04%) to eclampsia during their prenatal life. We identified 20260 people who received a diagnosis of epilepsy during up to 27 years of follow-up in the entire cohort. Prenatal exposure to preeclampsia was associated with an increased risk for epilepsy among children with a gestational age at birth of at least 37 weeks. For mild preeclampsia, the incidence rate ratios were 1.16 among children born at term and 1.68 for children born postterm; for severe preeclampsia, the incidence rate ratios were 1.41 among children born at term and 2.57 among children born postterm. No associations between preeclampsia and epilepsy were found among children who were born preterm. Eclampsia was associated with epilepsy with an incidence rate ratio of 1.29 for children born at term and 5.03 for children born postterm.

CONCLUSIONS

Prenatal exposure to both preeclampsia and eclampsia was associated with an increased risk of epilepsy in children born after 37 weeks of gestation.

Proton heating via nonresonant scattering off intrinsic Alfvénic turbulence

A novel yet unsophisticated theory is proposed to show that low-beta protons can be efficiently heated by enhanced Alfvén waves. The present research is motivated by a plasma physics issue relevant to the explanation of hot stellar coronas observed with x-ray telescopes. The efficient heating is attributed to nonresonant wave-particle scattering that tends to randomize proton motion in directions transverse to the ambient magnetic field.

Prevalence of dementia in rural China: impact of age, gender and education

OBJECTIVE

To determine the prevalence of dementia and Alzheimer's disease (AD) in rural China.

METHODS

A cross-sectional study was conducted within a cohort of adults older than 50 years of age in Linxian County, China. A Chinese version of the Mini-Mental State Examination (CMMSE) was used to screen cases of possible dementia. Three different cutoff points on CMMSE were applied depending on the participant's level of education. The participants then were given psychiatric interviews, medical and neurological examinations, and psychometric tests to ascertain the clinical diagnoses of dementia and AD.

RESULTS

Among the 16,095 participants, 5.26% were screened positive with 374 diagnosed as having dementia. Among them, AD accounted for 80.5%. The adjusted prevalence rates were 0.33%, 0.89%, 3.43%, and 8.19% in people in age groups 50-54, 55-64, 65-74, and 75 and above, respectively. The prevalence of AD correlated with the participant's level of education, and was 2.61%, 0.94%, and 0.56% in the illiterate group, in the primary school group, and in the middle school or higher group, respectively. Adjusted by education levels a higher prevalence in women was observed in the illiterate group.

CONCLUSIONS

The prevalence of dementia in this population is similar to that reported from other areas in mainland China and Taiwan with aging being a significant risk factor. After controlling for age, being a female and having received less number of years of education were associated with an higher prevalence of AD.

Heating of ions by Alfvén waves via nonresonant interactions

Finite-amplitude intrinsic Alfvén waves exist pervasively in astrophysical and solar-terrestrial environment. It is generally believed that linear wave-particle resonant interaction between thermal protons and Alfvén waves is ineffective when the proton beta is low. However, this Letter demonstrates that the ions can be heated by Alfvén waves via nonresonant nonlinear interaction. Contrary to the customary expectation, it is found that the lower the plasma beta value, the more effective is the heating process. It is also shown that the ion temperature increase is more prominent along perpendicular direction.

Microbial activity in a combined UASB-activated sludge reactor system

A combined upflow anaerobic sludge bed-activated sludge (UASB-AS) reactor system with consistently wasting of excess biomass was used to treat suspended-solids pre-settled piggery wastewater (COD=2000 mg l(-1), total Kjeldahl nitrogen TKN=400 mg l(-1), suspended solids=250-400 mg l(-1)). Thus, the activity of nitrogen-related microbial groups in each individual bioreactor was investigated. When the granules retention time (GRT) of 20-50 d in the UASB reactor, the solids retention time (SRT) of 10-25 d in the AS reactor and the recycle-to-influent ratio (Re) of 1 were maintained, the combined system removed 95-97% of chemical oxygen demand (COD), 100% of TKN and 54-55% of total nitrogen (TN). Denitrification and methanogenesis occurred in the UASB reactor so that both biochemical processes contributed to most of the COD removal and, complete nitrification (most of the TKN removal) occurred in the AS reactor. Compact granules with good settling abilities developed in the UASB reactor, and rapid rates of granulation of break-up granules in the UASB reactor were confirmed by experiments. The activity of nitrifiers and denitrifiers (an=0.68-0.87; adn=0.55-0.70) and the calculated specific nitrification and denitrification rates (qn=0.26-0.47 mg NH4+ -N mg VSS(-1)d(-1); qdn=0.046-0.076 mg NOx- -N mg VSS(-1)d(-1)) significantly increased with decreasing SRT and GRT, respectively. Accordingly, the combined UASB-AS reactor system should be regarded a promising alternative for the removal of organic carbon and nitrogen from piggery wastewater.

Evidence for suppression of superconductivity by spin imbalance in Co-Al-Co single-electron transistors

Spin imbalance can lead to suppression of superconductivity. We report the phenomena manifesting this effect under spin-polarized quasiparticle currents in ferromagnet-superconductor-ferromagnet single-electron transistors. The measured superconducting gap as a function of magnetic field reveals a dramatic decrease when the magnetizations of the two leads are misaligned. The effect of suppression increases with increasing source-drain voltage. A comparison with theoretical calculations is presented. This method may render it applicable to control superconductivity at low temperatures within low fields.

Long-term alterations in body weight do not affect the expression of melanocortin receptor-3 and -4 mRNA in the ovine hypothalamus

The pro-opiomelanocortin-derived peptides and the melanocortin receptors are implicated in various functions within the CNS including the regulation of food intake. In the present study, we used in situ hybridization, with specific 35S-labelled ovine riboprobes to map the expression of melanocortin receptor-3 (MC3-R) and -4 (MC4-R) mRNA in the diencephalon and brainstem of normal female sheep. Furthermore, we examined the effect of long-term alterations in energy balance on the distribution and expression of MC3-R and MC4-R mRNA in food-restricted and ad libitum-fed ovariectomized female sheep. The distribution of melanocortin receptors generally resembled that of the rat. A high number of MC3-R-labelled cells were seen in the ventral division of the lateral septum and the medial preoptic area. In the hypothalamus, a moderate number of MC3-R-labelled cells was observed in the lateral hypothalamic area while other nuclear groups had low to intermediate numbers of MC3-R-labelled cells. The distribution of MC4-R mRNA was generally similar to that of MC3-R mRNA in the septal/preoptic and hypothalamic regions, with a high number of labelled cells present in the intermediate division of the lateral septum. Within the hypothalamus, no MC4-R mRNA expression was observed in the arcuate nucleus. There was more widespread distribution of moderate to low numbers of MC4-R mRNA-expressing cells in the brainstem compared to that of MC3-R mRNA. Unlike findings in the rat, only a low number of cells expressed melanocortin receptor mRNA in the ovine hypothalamic nuclei associated with feeding behavior. The number of melanocortin receptor-labelled cells and the level of expression (silver grains/cell) in the hypothalamic feeding centers was similar in food-restricted and ad libitum-fed animals. These findings suggest that long-term alterations in metabolic status do not change the melanocortin receptor mRNA distribution and/or expression in the sheep hypothalamus.

Mouse melanocortin-4 receptor gene 5'-flanking region imparts cell specific expression in vitro

Weight homeostasis is exquisitely sensitive to changes in the abundance of melanocortin-4 receptor (MC4-R). To begin to understand the factors that regulate MC4-R gene expression, we determined there are no introns in the gene, there are multiple starts of transcription, and a cluster of 3' ends. A series of MC4-R-luciferase gene reporter chimerics was developed and transfected into cell lines expressing (UMR106; GT1-7; HEK293) and not expressing (Neuro 2A) endogenous MC4-R mRNA. The longest construct, which includes approximately 3.3 kb 5'-flanking, 425 bp 5'-untranslated (UTR) and 1852 bp 3'-flanking, significantly increased luciferase reporter gene expression 24-, 13-, and 3-fold compared to pGL3-basic when expressed in HEK293, UMR106, and GT1-7 cells, respectively. Deletion analysis of mMC4-R 5'-flanking cDNA identified full mMC4-R promoter activity within 178 bp upstream of the major start of transcription. The mMC4-R gene structure and reporter chimerics provide a fundamental framework for the identification of specific factors regulating MC4-R gene expression.