USH2A mutation analysis in 70 Dutch families with Usher syndrome type II

Usher syndrome type II (USH2) is characterised by moderate to severe high-frequency hearing impairment, progressive visual loss due to retinitis pigmentosa and intact vestibular responses. Three loci are known for USH2, however, only the gene for USH2a (USH2A) has been identified. Mutation analysis of USH2A was performed in 70 Dutch USH2 families. Ten mutations in USH2A were detected, of which three are novel, c.949C>A, c.2242C>T (p.Gln748X) and c.4405C>T (p.Gln1468X). Including 9 previously published Dutch USH2a families, estimates of the prevalence of USH2a in the Dutch USH2 population were made. Mutations were identified in 62% of the families. In 28% both mutated alleles were identified, whereas in 34% the mutation in only one allele was found. It is estimated that about 28% of the Dutch USH2 families have a different causative gene. Analysis of deduced haplotypes suggests that c.1256G>T (p.Cys419Phe) is a Dutch ancestral mutation, occurring in 16% of the alleles.     

Autoantibodies to vascular smooth muscle are pathogenic for vasculitis

We have previously shown that microvascular smooth muscle activates CD4+ T lymphocytes in sterile co-culture, presents antigen, and produces inflammatory cytokines. Adoptive transfer of lymphocytes co-cultured with syngeneic smooth muscle cells to healthy recipient mice results in vasculitic lesions predominantly in postcapillary venules. The present study assessed the pathogenic role of immunoglobulin and B cells in a murine model of vasculitis. Here, we show that transferred B cells, including plasmablast cells, accumulated, persisted, and proliferated in lung and secondary lymphoid organs of recipient mice. The induction of vasculitis was accompanied by production of IgM and IgG2a autoantibodies specific for vascular smooth muscle intracellular antigens. Circulating immunoglobulin had a pathogenic role in this vasculitis model, because the disease could be induced by transfer of serum from vasculitic mice to untreated animals but not by transfer of serum depleted of anti-smooth muscle autoantibodies. Additionally, the pathogenic mechanisms triggered by the transfer of vasculitogenic serum were dependent on T lymphocytes because both wild-type and B cell-deficient mice developed the disease after serum transfer, whereas RAG2-deficient mice did not. Thus, immunoglobulin and cell-mediated pathways work in concert to produce vasculitis in this model.     

Inhibition of vascular endothelial growth factor (VEGF) signaling in cancer causes loss of endothelial fenestrations, regression of tumor vessels, and appearance of basement membrane ghosts

Angiogenesis inhibitors are receiving increased attention as cancer therapeutics, but little is known of the cellular effects of these inhibitors on tumor vessels. We sought to determine whether two agents, AG013736 and VEGF-Trap, that inhibit vascular endothelial growth factor (VEGF) signaling, merely stop angiogenesis or cause regression of existing tumor vessels. Here, we report that treatment with these inhibitors caused robust and early changes in endothelial cells, pericytes, and basement membrane of vessels in spontaneous islet-cell tumors of RIP-Tag2 transgenic mice and in subcutaneously implanted Lewis lung carcinomas. Strikingly, within 24 hours, endothelial fenestrations in RIP-Tag2 tumors disappeared, vascular sprouting was suppressed, and patency and blood flow ceased in some vessels. By 7 days, vascular density decreased more than 70%, and VEGFR-2 and VEGFR-3 expression was reduced in surviving endothelial cells. Vessels in Lewis lung tumors, which lacked endothelial fenestrations, showed less regression. In both tumors, pericytes did not degenerate to the same extent as endothelial cells, and those on surviving tumor vessels acquired a more normal phenotype. Vascular basement membrane persisted after endothelial cells degenerated, providing a ghost-like record of pretreatment vessel number and location and a potential scaffold for vessel regrowth. The potent anti-vascular action observed is evidence that VEGF signaling inhibitors do more than stop angiogenesis. Early loss of endothelial fenestrations in RIP-Tag2 tumors is a clue that vessel phenotype may be predictive of exceptional sensitivity to these inhibitors.     

Kinetics of estimated human muscle capillary blood flow during recovery from exercise

The kinetic characteristics of muscle capillary blood flow (Qcap) during recovery from exercise are controversial (e.g. one versus two phases). Furthermore, it is not clear how the overall Qcap kinetics are temporally associated with muscle oxygen uptake (VO2m) kinetics. To address these issues, we examined the kinetics of Qcap estimated from the rearrangement of the Fick equation (Qcap=VO2m/C(a-v)O2) using the kinetics of pulmonary VO2 (VO2p, primary component) and deoxy-haemoglobin concentration ([HHb]) as indices of VO2m and C(a - v)O2 (arterio-venous oxygen difference) kinetics, respectively. VO2p (l min-1) was measured breath by breath and [HHb] (microm) was measured by near infrared spectroscopy during moderate (M; below lactate threshold, LT) and heavy exercise (H, above LT) in nine subjects. The kinetics of Qcap were biphasic, with an initial fast phase (tauI; M=9.3+/-4.9 s and H=6.0+/-3.8 s) followed by a slower phase 2 (tauP; M=29.9+/-8.6 s and H=47.7+/-26.0 s). For moderate exercise, the overall kinetics of Qcap (mean response time [MRT], 36.1+/-8.6 s) were significantly slower than the kinetics of VO2p (tauP; 27.8+/-5.3 s) and [HHb] (MRT for [HHb]; 16.2+/-6.3 s). However, for heavy exercise, there was no significant difference between MRT-[HHb] (34.7+/-10.4 s) and tauP for VO2p (32.3+/-6.7 s), while MRT for Qcap (48.7+/-21.8 s) was significantly slower than MRT for [HHb] and tauP for VO2p. In conclusion, during recovery from exercise the estimated Qcap kinetics were biphasic, showing an early rapid decrease in blood flow. In addition, the overall kinetics of Qcap were slower than the estimated VO2m kinetics.     

Relation of adolescent mothers' history of antisocial behavior to child conduct problems and social competence.

We examined the extent to which maternal antisocial behavior (ASB) is directly related to child conduct problems and social competence and assessed the potential mediating role of negative parenting. The sample included 93 adolescent mothers and their children (44 boys, 49 girls). Mothers retrospectively reported about their ASB since the child's birth, through Grade 2. Negative parenting was coded during a parent-child interaction task (PCIT) at Grade 2. Teachers assessed child outcomes at Grade 3. Maternal ASB during the child's life was directly related to parenting and both child outcomes. In the overall sample, negative parenting partially mediated the relation between maternal ASB and child conduct problems. However, the pattern of relations differed by sex. For boys, maternal ASB was directly related to conduct problems, independent of parenting. For girls, maternal ASB was strongly related to parenting but not conduct problems. Negative parenting did not mediate the relation between maternal ASB and child social competence. Implications for intervention and future research are discussed.     

Gene expression of the p85alpha regulatory subunit of phosphatidylinositol 3-kinase in skeletal muscle from type 2 diabetic subjects

The gene of the p85alpha regulatory subunit of phosphatidylinositol (PI) 3-kinase gives rise to several splice variants. We hypothesized that the expression of p85alpha splice variants may be altered in skeletal muscle from subjects with type 2 diabetes mellitus. Skeletal muscle biopsies were obtained from nine type 2 diabetic and eight healthy men, matched for age, body mass index (BMI) and physical fitness. PI 3-kinase activity in skeletal muscle following in vitro insulin stimulation was reduced in subjects with type 2 diabetes. p85alpha mRNA was elevated fourfold in type 2 diabetic as compared to healthy control subjects ( P<0.05). p85alpha mRNA abundance was positively correlated with plasma insulin concentration ( P<0.01) and serum glucose concentration ( P<0.01). Despite this, protein levels of p85alpha, p55alpha, and the novel human p50alpha were not altered in type 2 diabetic subjects. Thus, although gene expression of full-length p85alpha is increased in skeletal muscle from type 2 diabetics, this is not reflected by increased protein levels. Therefore, defects in PI 3-kinase activity are likely due to impaired activation of the enzyme rather than changes in protein expression of the isoforms of the regulatory subunit.     

Redox ratio of mitochondria as an indicator for the response of photodynamic therapy

The effect of photodynamic therapy (PDT) treatment on the metabolic state of tumor mitochondria is investigated by imaging of tumor redox status. PDT is performed using the photosensitizer pyropheophorbide-2-deoxyglucosamide (Pyro-2DG), which utilizes the glucose import pathway. It is found that Pyro-2DG-induced PDT resulting in a highly oxidized state of tumor mitochondria. This is determined from the redox ratio changes derived from the intrinsic oxidized flavoprotein (Fp) and reduced pyridine nucleotide (PN) [i.e., reduced nicotinamide adenine dinucleotide (NADH)] fluorescence signals observed using a cryoimager. Thus, the redox ratio is a sensitive indicator for providing reliable and informative measurements of PDT-induced tissue damage. In the PDT treated region of the tumor, highly oxidized flavoprotein and diminishing NADH fluorescence is detected, suggesting that flavoprotein and NADH are oxidized by singlet oxygen produced in the photosensitization process.     

Anxiety Treatment and Targeted Sleep Enhancement to Address Sleep Disturbance in Pre/Early Adolescents with Anxiety

Sleep disturbance is prevalent in anxious youth and prospectively predicts poor emotional adjustment in adolescence. Study 1 examined whether anxiety treatment improves subjective and objective sleep disturbance in anxious youth. Study 2 examined whether a sleep intervention called Sleeping TIGERS can further improve sleep following anxiety treatment. Study 1 examined 133 youth (ages 9–14; 56% female; 11% ethnic/racial minority) with generalized, social, or separation anxiety over the course of anxiety treatment (cognitive behavioral treatment or client-centered treatment). Sleep-related problems (parent-, child-report) and subjective (diary) and objective (actigraphy) sleep patterns were assessed across treatment in an open trial design. Study 2 included 50 youth (ages 9–14; 68% female; 10% ethnic/racial minority) who continued to report sleep-related problems after anxiety treatment and enrolled in an open trial of Sleeping TIGERS. Pre- and postassessments duplicated Study 1 and included the Focal Interview of Sleep to assess sleep disturbance. Study 1 demonstrated small reductions in sleep problems and improvements in subjective sleep patterns (diary) across anxiety treatment, but outcomes were not deemed clinically significant, and 75% of youth stayed above clinical cutoff. Study 2 showed clinically significant, large reductions in sleep problems and small changes in some subjective sleep patterns (diary). Anxiety treatment improves, but does not resolve, sleep disturbance in peri-pubertal youth, which may portend risk for poor emotional adjustment and mental health. The open trial provides preliminary support that Sleeping TIGERS can improve sleep in anxious youth to a clinically significant degree.     

Comparative efficacy,speed, and adverse effects of three PTSD treatments: exposure therapy,EMDR, and relaxation training

The authors examined the efficacy, speed, and incidence of symptom worsening for 3 treatments of posttraumatic stress disorder (PTSD): prolonged exposure, relaxation training, or eye movement desensitization and reprocessing (EMDR; N = 60). Treaments did not differ in attrition, in the incidence of symptom worsening, or in their effects on numbing and hyperarousal symptoms. Compared with EMDR and relaxation training, exposure therapy (a) produced significantly larger reductions in avoidance and reexperiencing symptoms, (b) tended to be faster at reducing avoidance, and (c) tended to yield a greater proportion of participants who no longer met criteria for PTSD after treatment. EMDR and relaxation did not differ from one another in speed or efficacy.