Genomic variants within chromosome 14q32.32 regulate bone mass through MARK3 signaling in osteoblasts

Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.     

Metabolism of deltamethrin and cis- and trans-permethrin by human expressed cytochrome P450 and carboxylesterase enzymes

1. The metabolism of the pyrethroids deltamethrin (DLM), cis-permethrin (CPM) and trans-permethrin (TPM) was studied in human expressed cytochrome P450 (CYP) and carboxylesterase (CES) enzymes.

2. DLM, CPM and TPM were metabolised by human CYP2B6 and CYP2C19, with the highest apparent intrinsic clearance (CL_int) values for pyrethroid metabolism being observed with CYP2C19. Other CYP enzymes contributing to the metabolism of one or more of the three pyrethroids were CYP1A2, CYP2C8, CYP2C9*1, CYP2D6*1, CYP3A4 and CYP3A5. None of the pyrethroids were metabolised by CYP2A6, CYP2E1, CYP3A7 or CYP4A11.

3. DLM, CPM and TPM were metabolised by both human CES1 and CES2 enzymes.

4. Apparent CL_int values for pyrethroid metabolism by CYP and CES enzymes were scaled to per gram of adult human liver using abundance values for microsomal CYP enzymes and for CES enzymes in liver microsomes and cytosol. TPM had the highest and CPM the lowest apparent CL_int values for total metabolism (CYP and CES enzymes) per gram of adult human liver.

5. Due to their higher abundance, all three pyrethroids were extensively metabolised by CES enzymes in adult human liver, with CYP enzymes only accounting for 2%, 10% and 1% of total metabolism for DLM, CPM and TPM, respectively.

     

Multiple Cerebral Haematomata and Peripheral Nerve Palsies Associated with a Case of Juvenile Diabetic Ketoacidosis

A 15-year-old girl presented de novo in diabetic ketoacidosis having been comatose for 24 h (day 1). A CT scan and lumbar puncture performed on admission were normal and her conscious level slowly improved over several days. On day 7 she had central neurological signs of bilateral knee clonus and an extensor plantar response. In addition, she had developed lower motor neurological signs of an ulnar nerve palsy of the left forearm, and ulnar, median, and radial nerve palsies of the right forearm. Magnetic resonance imaging (MRI), performed on day 12, showed multiple small cerebral haematomata with appearances at least several days of age. The scattered lesions were localized particularly to the parieto-occipital region, with sparing of the basal ganglia and without cerebral oedema, a novel feature not previously described in juvenile ketoacidosis. Four months later there was minimal residual disability of her right arm. The clinical findings together with the MRI images suggested that the peripheral nerve and central lesions were temporally related, suggesting a common aetiology. However, it is likely that MRI showed cerebral lesions which may have been missed by the conventional CT scanning performed initially.     

Development of a new Adolescent Patient-Provider Interaction Scale (APPIS) for youth at risk for STDs/HIV

PurposeAlthough an adult model of patient-provider mutual exchange of information has been proposed, there is no guiding model for adolescents or measurement methodology. Our purpose was to develop a new scale of patient-provider interaction for adolescents accessing reproductive health care and at risk for sexually transmitted diseases (STDs) and human immunodeficiency virus (HIV), and assess the reliability and validity of the scale.MethodsThe Adolescent Patient-Provider Interaction Scale (APPIS) was developed from the Roter and Hall theory of doctor-patient relationships, previously validated adolescent satisfaction and communication scales, and focus group and individual elicitation interviews. To assess construct validity, the new nine-item APPIS was compared with the satisfaction scale used by the Young Adult Health Care Survey (YAHCS), and Kahn’s Provider Communication Scale. Pearson correlation coefficients were used to examine convergence across scales, and factor analysis of the APPIS was performed.ResultsThe study recruited 192 African American girls aged 17.9 ± 1.7 years (range 15–21 years) from three sites: a county STD clinic (n = 51), urban adolescent clinic (n = 99), and a family planning clinic (n = 42). Most participants (85%) rated their overall health care highly (≥ 7 on a 10-point scale); 49% felt that both the provider and patient were “in charge” of the visit, and 88% “strongly agreed” or “agreed” that there was an equal “exchange of information” during the visit. The APPIS showed good internal consistency (Cronbach alpha = .75), and moderate convergence with the six-item YAHCS scale (r = .57, p < .001) and seven-item Kahn scale (r = .48, p < .001). Three factors emerged from exploratory factor analyses, supporting our conceptualization of patient-provider interaction as being multi-dimensional.ConclusionsA new theory-based scale of adolescent patient-provider interaction compares favorably with previous scales of health care satisfaction and communication. The new APPIS may be useful for evaluating approaches to improve health care outcomes for adolescents at-risk for STDs and HIV.     

What proteins are present in polyethylene glycol precipitates from rheumatic sera?

The proteins present in 4% polyethylene glycol (PEG) precipitates of 10 normal sera and 60 samples from patients with rheumatic diseases were studied. A variety of immunochemical methods were used, including estimation of the percentages of total serum proteins precipitated by PEG, gel filtration analyses of the precipitates, and affinity chromatography with protein A and anti-immunoglobulin columns. Substantial amounts of protein were precipitated from normal sera. Many non-immunoglobulin proteins were precipitated from patients' sera, including fibronectin, haptoglobin, albumin, transferrin, and alpha 1-antitrypsin. Affinity chromatography with anti-immunoglobulin columns bound non-immunoglobulin proteins from PEG precipitates, but the protein A affinity column did not do so. The view that circulating antibody-antigen complexes alone are precipitated by 4% PEG is too simplistic; many non-immunoglobulin proteins are involved. They may either bind to immune complexes or be coprecipitated owing to non-specific protein aggregation.     

Genetic diversity and molecular identification of mosquito species in the Anopheles maculatus group using the ITS2 region of rDNA.

The species diversity and genetic structure of mosquitoes belonging to the Anopheles maculatus group in Southeast Asia were investigated using the internal transcribed spacer 2 (ITS2) of ribosomal DNA (rDNA). A molecular phylogeny indicates the presence of at least one hitherto unrecognised species. Mosquitoes of chromosomal form K from eastern Thailand have a unique ITS2 sequence that is 3.7% divergent from the next most closely related taxon (An. sawadwongporni) in the group. In the context of negligible intraspecific variation at ITS2, this suggests that chromosomal form K is most probably a distinct species. Although An. maculatus sensu stricto from northern Thailand and southern Thailand/peninsular Malaysia differ from each other in chromosomal banding pattern and vectorial capacity, no intraspecific variation was observed in the ITS2 sequences of this species over this entire geographic area despite an extensive survey. A PCR-based identification method was developed to distinguish five species of the group (An. maculatus, An. dravidicus, An. pseudowillmori, An. sawadwongporni and chromosomal form K) to assist field-based studies in northwestern Thailand. Sequences from 187 mosquitoes (mostly An. maculatus and An. sawadwongporni) revealed no intraspecific variation in specimens from Thailand, Cambodia, mainland China, Malaysia, Taiwan and Vietnam, suggesting that this identification method will be widely applicable in Southeast Asia. The lack of detectable genetic structure also suggests that populations of these species are either connected by gene flow and/or share a recent common history.