Blood Lead Concentration and Thyroid Function during Pregnancy: Results from the Yugoslavia Prospective Study of Environmental Lead Exposure

Background: Although maternal hypothyroidism increases the risk of adverse neonatal and obstetric outcomes as well as lower IQ in children, the environmental determinants of maternal thyroid dysfunction have yet to be fully explored.Objectives: We aimed to examine associations between mid-pregnancy blood lead (BPb) and concomitant measures of thyroid function among participants in the Yugoslavia Prospective Study of Environmental Lead Exposure.Methods: As part of a population-based prospective study of two towns in Kosovo—one with high levels of environmental lead and one with low—women were recruited during the second trimester of pregnancy, at which time blood samples and questionnaire data were collected. We measured concentrations of BPb, free thyroxine (FT₄), thyroid-stimulating hormone (TSH), and thyroid peroxidase antibodies (TPOAb) in archived serum samples.Results: Compared with women from the unexposed town, women from the exposed town had lower mean FT₄ (0.91 ± 0.17 vs. 1.03 ± 0.16 ng/dL), higher mean TPOAb (15.45 ± 33.08 vs. 5.12 ± 6.38 IU/mL), and higher mean BPb (20.00 ± 6.99 vs. 5.57 ± 2.01 μg/dL). No differences in TSH levels were found. After adjustment for potential confounders, for each natural log unit increase in BPb, FT₄ decreased by 0.074 ng/dL (95% CI: –0.10, –0.046 ng/dL), and the odds ratio for testing positive to TPOAb was 2.41 (95% CI: 1.53, 3.82). We found no association between BPb and TSH.Conclusions: Prolonged lead exposure may contribute to maternal thyroid dysfunction by stimulating autoimmunity to the thyroid gland.Citation: Kahn LG, Liu X, Rajovic B, Popovac D, Oberfield S, Graziano JH, Factor-Litvak P. 2014. Blood lead concentration and thyroid function during pregnancy: results from the Yugoslavia Prospective Study of Environmental Lead Exposure. Environ Health Perspect 122:1134–1140; http://dx.doi.org/10.1289/ehp.1307669     

Genetic Diversity and Population Structure of Kenyan Common Bean ( Phaseolus vulgaris L.) Germplasm Using Peroxidase Gene Markers

Common bean (Phaseolus vulgaris L.) is a vital legume used as human food, source of cash income, feed for livestock, and it increases the fertility of soil by its ability to fix nitrogen. The aim of this research was to determine the genetic diversity and population structure of 40 common bean germplasm cultivated in Kenya, using peroxidase gene (POX)-based molecular markers. The loci analyzed showed high diversity and amplified 624 alleles, ranging from 3 to 9 on every locus, with an average of 7.20. The PIC of the POX markers varied from 0.6204 to 0.9110, with an average of 0.7677. The range of the observed heterozygosity was from 0.6667 to 0.9150 with a mean of 0.7945, while the values of the mean genetic diversity ranged from 0.3072 to 0.4425 with a mean of 0.3972. The UPGMA phenogram separated the genotypes into two main genetic clusters, and the genotypes showed no grouping by geographical origins. The highest value of genetic variation was observed between the genotypes obtained from Western, Rift valley and Central regions of Kenya. Population structure analysis grouped the germplasm into 7 gene pools and showed that the genotypes have a common genetic lineage. AMOVA revealed higher genetic diversity (99%) within population than among population (1%), and this offers a reliable base for the design of genetic improvement schemes. Results of the present study can be used in future breeding programs and for the genetic improvement in common bean.     

Complex Partial Seizure Provocation by Vasovagal Syncope: Video-EEG and Intracranial Electrode Documentation

Summary: Vasovagal syncope precipitating an epileptic seizure has only rarely been described. A patient with known intractable complex partial seizures being evaluated for a left anterior temporal lobectomy experienced a typical seizure with mesial temporal onset precipitated by an observed vasovagal episode. This is the first report of a partial epileptic seizure precipitated by vasovagal syncope and the first example of an epileptic seizure induced by syncope in an adult. Video and intracranial depth electrode and subdural grid recordings documented the event.     

Isolation of myelinoid Marchi-positive bodies from normal rabbit spinal cord

Normal rabbit spinal cord was homogenized in sucrose and fractionated by centrifugation in a sucrose density gradient system slightly modified after the Norton-Poduslo method for the isolation of myelin. The following fractions were recovered: the fraction floating on 0.32 M sucrose, the myelin fraction at the 0.32 M/0.85 M interface and the pellet. After fixation in glutaraldehyde the fractions were subjected to Marchi staining, a histochemical method used for the demonstration of degenerating myelin. The floating fraction was enriched in Marchi-positive bodies as compared to the homogenate while the myelin fraction and the pellet contained low amounts. No esterified cholesterol was found in the floating fraction. Since histochemical and electron microscopical studies have shown that Marchi-positive myelinoid bodies in the normal CNS are associated with node-paranode regions our results indicate a possibility to isolate and biochemically characterize a presumably closely myelin-related fraction of known anatomical origin. The absence of esterified cholesterol in the floating fraction shows that biochemical or biophysical properties other than a content of esterified cholesterol may give rise to a positive Marchi reaction.     

Mapping Canadian Data Assets to Generate Real-World Evidence: Lessons Learned from Canadian Real-World Evidence for Value of Cancer Drugs (CanREValue) Collaboration’s RWE Data Working Group

Canadian provinces routinely collect patient-level data for administrative purposes. These real-world data (RWD) can be used to generate real-world evidence (RWE) to inform clinical care and healthcare policy. The CanREValue Collaboration is developing a framework for the use of RWE in cancer drug funding decisions. A Data Working Group (WG) was established to identify data assets across Canada for generating RWE of oncology drugs. The mapping exercise was conducted using an iterative scan with informant surveys and teleconference. Data experts from ten provinces convened for a total of three teleconferences and two in-person meetings from March 2018 to September 2019. Following each meeting, surveys were developed and shared with the data experts which focused on identifying databases and data elements, as well as a feasibility assessment of conducting RWE studies using existing data elements and resources. Survey responses were compiled into an interim data report, which was used for public stakeholder consultation. The feedback from the public consultation was used to update the interim data report. We found that databases required to conduct real-world studies are often held by multiple different data custodians. Ninety-seven databases were identified across Canada. Provinces held on average 9 distinct databases (range: 8–11). An Essential RWD Table was compiled that contains data elements that are necessary, at a minimal, to conduct an RWE study. An Expanded RWD Table that contains a more comprehensive list of potentially relevant data elements was also compiled and the availabilities of these data elements were mapped. While most provinces have data on patient demographics (e.g., age, sex) and cancer-related variables (e.g., morphology, topography), the availability and linkability of data on cancer treatment, clinical characteristics (e.g., morphology and topography), and drug costs vary among provinces. Based on current resources, data availability, and access processes, data experts in most provinces noted that more than 12 months would be required to complete an RWE study. The CanREValue Collaboration’s Data WG identified key data holdings, access considerations, as well as gaps in oncology treatment-specific data. This data catalogue can be used to facilitate future oncology-specific RWE analyses across Canada.