Iodine status and thyroid function among Spanish schoolchildren aged 6-7 years: the Tirokid study.

I deficiency is still a worldwide public health problem, with children being especially vulnerable. No nationwide study had been conducted to assess the I status of Spanish children, and thus an observational, multicentre and cross-sectional study was conducted in Spain to assess the I status and thyroid function in schoolchildren aged 6-7 years. The median urinary I (UI) and thyroid-stimulating hormone (TSH) levels in whole blood were used to assess the I status and thyroid function, respectively. A FFQ was used to determine the consumption of I-rich foods. A total of 1981 schoolchildren (52 % male) were included. The median UI was 173 µg/l, and 17·9 % of children showed UI<100 µg/l. The median UI was higher in males (180·8 v. 153·6 µg/l; P<0·001). Iodised salt (IS) intake at home was 69·8 %. IS consumption and intakes of ≥2 glasses of milk or 1 cup of yogurt/d were associated with significantly higher median UI. Median TSH was 0·90 mU/l and was higher in females (0·98 v. 0·83; P<0·001). In total, 0·5 % of children had known hypothyroidism (derived from the questionnaire) and 7·6 % had TSH levels above reference values. Median TSH was higher in schoolchildren with family history of hypothyroidism. I intake was adequate in Spanish schoolchildren. However, no correlation was found between TSH and median UI in any geographical area. The prevalence of TSH above reference values was high and its association with thyroid autoimmunity should be determined. Further assessment of thyroid autoimmunity in Spanish schoolchildren is desirable.

Maternal exposure to methotrexate and birth defects: a population-based study.

Methotrexate is an anti-folate medication that is associated with increased risk of multiple birth defects. Using data from the National Birth Defects Prevention Study, a case-control study of major birth defects in the United States, we examined mothers exposed to methotrexate. The study population included mothers of live-born infants without major birth defects (controls) and mothers of fetuses or infants with a major birth defect (cases), with expected dates of delivery between October 1997 and December 2009. Mothers of cases and controls were asked detailed questions concerning pregnancy history, demographic information, and exposures in a telephone interview. Approximately 0.06% (n = 16/27,623) of case and 0.04% (n = 4/10,113) of control mothers reported exposure to methotrexate between 3 months prior to conception through the end of pregnancy. Of the 16 case infants, 11 (68.8%) had a congenital heart defect (CHD). The observed CHDs included atrial septal defects, tetralogy of Fallot, valvar pulmonary stenosis, ventricular septal defects (VSDs), and total anomalous pulmonary venous return. One case infant had microtia in addition to a VSD and another had VACTER association. Exposed cases without a CHD had one of the following birth defects: cleft palate, hypospadias, congenital diaphragmatic hernia, or craniosynostosis. Based on a limited number of methotrexate-exposed mothers, our findings support recent case reports suggesting an association between early pregnancy exposure to methotrexate and CHDs. Because of the rarity of maternal periconceptional exposure to methotrexate, long-term, population-based case-control studies are needed to confirm these findings and better evaluate the association between methotrexate and birth defects.

A promoter mutation in the XIST gene in two unrelated families with skewed X-chromosome inactivation.

X-chromosome inactivation is the process by which a cell recognizes the presence of two copies of an X chromosome early in the development of XX embryos and chooses one to be active and one to be inactive. Although it is commonly believed that the initiation of X inactivation is random, with an equal probability (50:50) that either X chromosome will be the inactive X in a given cell, significant variation in the proportion of cells with either X inactive is observed both in mice heterozygous for alleles at the Xce locus and among normal human females in the population. Families in which multiple females demonstrate extremely skewed inactivation patterns that are otherwise quite rare in the general population are thought to reflect possible genetic influences on the X-inactivation process. Here we report a rare cytosine to guanine mutation in the XIST minimal promoter that underlies both epigenetic and functional differences between the two X chromosomes in nine females from two unrelated families. All females demonstrate preferential inactivation of the X chromosome carrying the mutation, suggesting that there is an association between alterations in the regulation of XIST expression and X-chromosome inactivation.

Structure of the colcemid-treated PtK1 kinetochore outer plate as determined by high voltage electron microscopic tomography.

High voltage electron microscopic tomography was used to determine the organization of the kinetochore plate and its attachment to the underlying chromosome. Six reconstructions were computed from thick sections of Colcemid-treated PtK1 cells and analyzed by a number of computer graphics methods including extensive thin slicing, three-dimensional masking, and volume rendering. When viewed en-face the kinetochore plate appeared to be constructed from a scaffold of numerous 10-20-nm thick fibers or rods. Although the fibers exhibited regions of parallel alignment and hints of a lattice, they were highly variable in length, orientation and spacing. When viewed in stereo, groups of these fibers were often seen oriented in different directions at different depths to give an overall matted appearance to the structure. When viewed "on edge," the plate was 35-40 nm thick, and in thin slices many regions were tripartite with electron-opaque domains, separated by a more translucent middle layer, forming the inner and outer plate boundaries. These domains were joined at irregular intervals. In some slices, each domain appeared as a linear array of 10-20-nm dots or rods embedded in a less electron-opaque matrix, and adjacent dots within or between domains often appeared fused to form larger blocks. The plate was connected to the underlying chromosome by less densely arrayed 10-20-nm thick fibers that contacted the chromosome-facing (i.e., inner) surface of the plate in numerous patches. These patches tended to be arrayed in parallel rows perpendicular to the long axis of the chromosome. In contrast to connecting fibers, corona fibers were more uniformly distributed over the cytoplasmic-facing (i.e., outer) surface of the plate. When large portions of the reconstructions were viewed, either en-face or in successive slices parallel to the long axis of the chromosome, the edges of the plate appeared splayed into multiple "fingers" that partly encircled the primary constriction. Together these observations reveal that regions of the kinetochore outer plate contain separate structural domains, which we hypothesize to serve separate functional roles. Our three-dimensional images of the kinetochore are largely consistent with the hypothesis that the outer plate is composed of multiple identical subunits (Zinkowski, R. P., J. Meyne, and B. R. Brinkley. 1991. J. Cell Biol. 113:1091-1110).

A receptor in pituitary and hypothalamus that functions in growth hormone release.

Small synthetic molecules termed growth hormone secretagogues (GHSs) act on the pituitary gland and the hypothalamus to stimulate and amplify pulsatile growth hormone (GH) release. A heterotrimeric GTP-binding protein (G protein)-coupled receptor (GPC-R) of the pituitary and arcuate ventro-medial and infundibular hypothalamus of swine and humans was cloned and was shown to be the target of the GHSs. On the basis of its pharmacological and molecular characterization, this GPC-R defines a neuroendocrine pathway for the control of pulsatile GH release and supports the notion that the GHSs mimic an undiscovered hormone.

Arrhythmia susceptibility and myocardial composition in diabetes. Influence of physical conditioning.

Abnormal myocardial composition in diabetes mellitus has been described, but the effects on ventricular vulnerability have not been defined. We have assessed the susceptibility to arrhythmias in a canine model after 1 yr of mild diabetes induced by alloxan. Since physical conditioning can affect metabolic abnormalities in diabetes, this intervention has also been evaluated. Group 1 served as controls and groups 3 and 4 were diabetic. Animals in the latter group as well as nondiabetic controls of group 2 were exercised on a treadmill for the last 8 mo of the experiment. After 1 yr, anesthesia was induced with chloralose for vulnerability studies. The ventricular fibrillation threshold of 24.4 +/- 1.9 mA in group 3 was significantly less than in normals (45.1 +/- 2.2). Spontaneous arrhythmias were also more prevalent in diabetics during acute ischemia (group 3-A). Increased ventricular vulnerability after epinephrine infusion was present in the sedentary diabetes despite normal ventricular function responsiveness. In a superfused preparation of myocardium, resting membrane potential and action potential amplitude were normal in diabetics, and beta-adrenergic stimulation shortened repolarization more than in controls. Myocardial collagen concentrations, which included an interfibrillar distribution on morphologic examination, were increased in group 3. In the trained diabetics of group 4 the basal vulnerability thresholds and responses to epinephrine were normal. While myocardial collagen levels were normal, cholesterol and triglyceride increments persisted. Thus, in mild experimental diabetes, enhanced susceptibility to arrhythmias exists; this susceptibility may be based on a combination of nonhomogenous collagen accumulation affecting local conduction and increased electrophysiologic sensitivity to catecholamines.

Characterizing the Pattern of Anomalies in Congenital Zika Syndrome for Pediatric Clinicians.

Importance: Zika virus infection can be prenatally passed from a pregnant woman to her fetus. There is sufficient evidence to conclude that intrauterine Zika virus infection is a cause of microcephaly and serious brain anomalies, but the full spectrum of anomalies has not been delineated. To inform pediatric clinicians who may be called on to evaluate and treat affected infants and children, we review the most recent evidence to better characterize congenital Zika syndrome. Observations: We reviewed published reports of congenital anomalies occurring in fetuses or infants with presumed or laboratory-confirmed intrauterine Zika virus infection. We conducted a comprehensive search of the English literature using Medline and EMBASE for Zika from inception through September 30, 2016. Congenital anomalies were considered in the context of the presumed pathogenetic mechanism related to the neurotropic properties of the virus. We conclude that congenital Zika syndrome is a recognizable pattern of structural anomalies and functional disabilities secondary to central and, perhaps, peripheral nervous system damage. Although many of the components of this syndrome, such as cognitive, sensory, and motor disabilities, are shared by other congenital infections, there are 5 features that are rarely seen with other congenital infections or are unique to congenital Zika virus infection: (1) severe microcephaly with partially collapsed skull; (2) thin cerebral cortices with subcortical calcifications; (3) macular scarring and focal pigmentary retinal mottling; (4) congenital contractures; and (5) marked early hypertonia and symptoms of extrapyramidal involvement. Conclusions and Relevance: Although the full spectrum of adverse reproductive outcomes caused by Zika virus infection is not yet determined, a distinctive phenotype-the congenital Zika syndrome-has emerged. Recognition of this phenotype by clinicians for infants and children can help ensure appropriate etiologic evaluation and comprehensive clinical investigation to define the range of anomalies in an affected infant as well as determine essential follow-up and ongoing care.

Retrospective cohort analysis of neoadjuvant treatment and survival in resectable and borderline resectable pancreatic ductal adenocarcinoma in a high volume referral centre.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease. Neoadjuvant therapy (NA) with chemotherapy (NAC) and radiotherapy (RT) prior to surgery provides promise. In the absence of prospective data, well annotated clinical data from high-volume units may provide pilot data for randomised trials. METHODS: Medical records from a tertiary hospital in Sydney, Australia, were analysed to identify all patients with resectable or borderline resectable PDAC. Data regarding treatment, toxicity and survival were collected. RESULTS: Between January 1 2010 and April 1 2016, 220 sequential patients were treated: 87 with NA and 133 with upfront operation (UO). Forty-three NA patients (52%) and 5 UO patients (4%) were borderline resectable at diagnosis. Twenty-four borderline patients received NA RT, 22 sequential to NAC. The median overall survival (OS) in the NA group was 25.9 months (mo); 95% CI (21.1-43.0 mo) compared to 26.9 mo (19.7, 32.7) in the UO; HR 0.89; log-ranked p-value = 0.58. Sixty-nine NA patients (79%) were resected, mOS was 29.2 mo (22.27, not reached (NR)). Twenty-two NA (31%) versus 22 UO (17%) were node negative at operation (N0). In those managed with NAC/RT the mOS was 29.0 mo (17.3, NR). There were no post-operative deaths with NA within 90-days and three in the UO arm. DISCUSSION: This is a hypothesis generating retrospective review of a selected real-world population in a high-throughput unit. Treatment with NA was well tolerated. The long observed survival in this group may be explained by lymph node sterilisation by NA, and the achievement of R0 resection in a greater proportion of patients.

Influence of white matter MRI hyper-intensities on acute l-dopa response in patients with Parkinson's disease.

OBJECTIVE: To determine whether brain white matter hyperintensities (WMH) influence l-dopa response in Parkinson's disease (PD) patients. METHODS: We prospectively evaluated 60 PD patients with an acute l-dopa challenge test, and assessed motor performance with the Movement Disorders Society revised Unified Parkinson's Disease Rating Scale (MDS-UPDRS) during "ON" and "OFF" medication states. Magnetic resonance images were examined using a visual semi-quantitative rating scale for quantification and distribution analysis of WMH. l-dopa challenge test response was correlated to extent and location of WMH, to determine a potential association between them. RESULTS: Subjects with greater deep WMH burden, showed less response to l-dopa on axial motor symptoms (R = -0.35; p < 0.027), when tested with Part III of the MDS-UPDRS before and after acute levodopa challenge. CONCLUSIONS: Results suggest WMH may affect response to l-dopa on axial function of PD patients, which could be due to either non-dopaminergic (cortico-basal ganglia) motor pathway disruption, or postsynaptic nigrostriatal pathway involvement.

Transverse closure of mesenterico-portal vein after vein resection in pancreatoduodenectomy.

BACKGROUND: Resection of the involved mesenteric-portal vein (MPV) is increasingly performed in pancreatoduodenectomy. The primary aim of this study is to assess the rate of R0 resection in transverse closure (TC) versus segmental resection with end-to-end (EE) closure and the secondary aims are to assess the short-term morbidity and long-term survival of TC versus EE. METHODS: Patients undergoing pancreatoduodenectomy with MPV resection were identified from a prospectively database. The reconstruction technique were examined and categorized. Clinical, pathological, short-term and long-term survival outcomes were compared between groups. RESULTS: 110 patients underwent PD with MPV resection of which reconstruction was performed with an end-to-end technique in 92 patients (84%) and transverse closure technique in 18 patients (16%). Patients undergoing transverse closure tended to have had a shorter segment of vein resected (≤2 cm) compared to the end-to-end (83% vs. 43%; P = 0.004) with no difference in R0 rate. Short-term morbidity was similar. The median and 5-year survival was 30.0 months and 18% respectively for patients undergoing transverse closure and 28.6 months and 7% respectively for patients undergoing end-to-end reconstruction (P = 0.766). CONCLUSION: Without compromising the R0 rate, transverse closure to reconstruct the mesenteric-portal vein is shown to be feasible and safe in the setting when a short segment of vein resection is required during pancreatoduodenectomy. Synopsis - We describe a vein closure technique, transverse closure, which avoids the need for a graft, or re-implantation of the splenic vein when resection of the mesenteric-portal vein confluence is required during pancreatoduodenectomy.

Influence of pHo on calcium channel block by amlodipine, a charged dihydropyridine compound. Implications for location of the dihydropyridine receptor.

We have investigated the modulation of L-type calcium channel currents in isolated ventricular cells by the dihydropyridine derivative amlodipine, a weak base with a pKa of 8.6. Under conditions that favor neutral drug molecules, amlodipine block resembles other, previously described, neutral dihydropyridine derivatives: block is more pronounced at depolarized voltages, repetitive pulsing is not needed to promote block, and recovery is complete at hyperpolarized voltages. When the drug is ionized, depolarized voltages still enhance block, however, the time course is slow and speeded by repetitive pulses that open channels. Recovery from block by ionized drug molecules is very slow and incomplete, but can be rapidly modified by changes in external hydrogen ion concentration. We conclude from these observations that the degree of ionization of the drug molecule can affect access to the dihydropyridine receptor and that external protons can interact with the drug-receptor complex even if channels are blocked and closed. These observations place limitations on the location of this receptor in the ventricular cell membrane.

Block of L-type calcium channels by charged dihydropyridines. Sensitivity to side of application and calcium.

We have studied block of L-type calcium channels by intracellular and extracellular application of the ionized dihydropyridine derivatives amlodipine and SDZ 207-180. We find that extracellular application of either drug causes voltage-dependent block of calcium channels. However, neither drug is effective when applied intracellularly. The insensitivity of calcium channels to intracellular drug is not due to the low concentrations of cytosolic calcium, because voltage-dependent block by ionized amlodipine, SDZ 207-180, and the neutral drug nisoldipine persists under conditions in which Ca0 is buffered by EGTA. In fact, the time course of the development of block by the ionized but not neutral drug molecules studied, is slower in the presence than in the absence of calcium. Our results indicate that the DHP binding site of the L-type calcium channel is close to the extracellular surface of the cell membrane and that ionized DHP molecules may interact with the receptor in a manner that is uniquely affected by calcium.

Functional expression of Drosophila para sodium channels. Modulation by the membrane protein TipE and toxin pharmacology.

The Drosophila para sodium channel alpha subunit was expressed in Xenopus oocytes alone and in combination with tipE, a putative Drosophila sodium channel accessory subunit. Coexpression of tipE with para results in elevated levels of sodium currents and accelerated current decay. Para/TipE sodium channels have biophysical and pharmacological properties similar to those of native channels. However, the pharmacology of these channels differs from that of vertebrate sodium channels: (a) toxin II from Anemonia sulcata, which slows inactivation, binds to Para and some mammalian sodium channels with similar affinity (Kd congruent with 10 nM), but this toxin causes a 100-fold greater decrease in the rate of inactivation of Para/TipE than of mammalian channels; (b) Para sodium channels are >10-fold more sensitive to block by tetrodotoxin; and (c) modification by the pyrethroid insecticide permethrin is >100-fold more potent for Para than for rat brain type IIA sodium channels. Our results suggest that the selective toxicity of pyrethroid insecticides is due at least in part to the greater affinity of pyrethroids for insect sodium channels than for mammalian sodium channels.

Skin to calcaneus distance in the neonate.

BACKGROUND: Current recommendations for obtaining blood from neonates advise avoidance of the midline area of the heel and are based on postmortem studies. OBJECTIVE: Because of the potential pain and tissue damage from repeated heel pricking in the same area, to investigate using ultrasonography whether the distance from skin to calcaneus is less at the midline than at the borders. METHODS: One hundred consecutive healthy preterm and 105 consecutive healthy term neonates were studied 48-72 hours after delivery. The skin to perichondrium distance (SPD) was measured on two occasions by ultrasound at the external, midline, and internal areas of the heel. FINDINGS: Mean SPD was 0.2 mm less at the midline than at the other sites. The proportion of measurements <3 mm at any of the three sites was the same. Depth was <3 mm in less than 3% of the term and approximately 20% of the preterm infants. The SPD correlated only with gestational age. Of children <33 weeks gestational age, 38% had an SPD <3 mm compared with 8% of older preterm infants. The proportions of preterm infants of > or = 33 weeks gestation and term infants with an SPD <3 mm were similar (8% v 3%). INTERPRETATION: With the use of automated lancets of 2.2 mm length or less, the whole heel plantar surface is safe for obtaining blood in term and preterm infants of > or = 33 weeks gestation. This means that soft tissue damage and pain from repeated pricking in the same area can be reduced.

A new X linked mental retardation (XLMR) syndrome with short stature, small testes, muscle wasting, and tremor localises to Xq24-q25.

METHODS: A large family is described in which mental retardation segregates as an X linked trait. Six affected males in three generations were studied by linkage and clinical examination. RESULTS: Characteristic clinical features include short stature, prominent lower lip, small testes, muscle wasting of the lower legs, kyphosis, joint hyperextensibility, abnormal gait, tremor, and decreased fine motor coordination. Affected subjects also had impaired speech and decreased attention span. A carrier female was mildly affected. A similar disorder was not found on review of our XLMR Database of 124 syndromes. Linkage analysis of 37 markers resulted in a lod score of 2.80 at DXS1212 and 2.76 at DXS425. The limiting markers were DXS424 and DXS1047. Ten of 124 XLMR syndromes and eight of 58 MRX families overlap this region. CONCLUSIONS: In summary, this family appears to have a new XLMR syndrome localising to Xq24-q25.

Relationship between mutation genotype and biochemical phenotype in a heterogeneous Spanish phenylketonuria population.

Genotyping of the phenylalanine hydroxylase (PAH) gene offers a new tool for characterizing patients with phenylketonuria (PKU), refining the diagnosis and aiding in the prediction of the clinical outcome and in the implementation of a more adequate treatment. The primary goal of this work was the detailed study of the different allele combinations and the metabolic phenotypes in Spanish PKU patients in order to understand better the clinical heterogeneity of PAH deficiency in our population. The results show that the disease phenotype is a consequence of a combination of mutations at the PAH locus and this observation is valid throughout the spectrum of clinical and biochemical varieties found in Spanish PKU patients. A stronger correlation was found between the predicted residual activity, when known from previous in vitro studies of the mutant proteins, and the Phe tolerance than between the predicted residual activity and the inverse of Phe levels at diagnosis. The observed genotype-phenotype correlations and the available data on the in vitro residual activity of the mutant proteins has enabled the estimation of the severity of most of the mutations found in Spain. This study includes relevant data for clinicians and pediatricians adding to the present knowledge which relates allelic PAH genotypes to biological phenotypes.

Genetic and phenotypic aspects of phenylalanine hydroxylase deficiency in Spain: molecular survey by regions.

We present an extensive study of the genetic diversity of phenylalanine hydroxylase deficiency in the Spanish phenylketonuria population. We have analysed 195 PKU patients by DGGE analysis identifying 67 different mutations which represent 89% of the total mutant chromosomes. Seventeen mutations first described in Spain have not yet been detected elsewhere; ten of these are reported here for the first time. The clinical significance of this high genetic heterogeneity was examined by analysing the genotype-phenotype correlations, mainly focusing on the mild hyperphenylalaninaemia (MHP) phenotype. The genotypes found in a group of 93 MHP patients, the largest analysed so far, are described in detail, as well as the relative frequencies of the MHP mutations identified. From the total pool of mutations, 27 can be considered severe, 18 can be defined as mild and 13 as associated with MHP. The prevalent mutations correspond to one severe mutation (IVS10nt-11), one MHP mutation (A403V) and two mild mutations (165T and V388M). The high frequency of mutations with a low degree of severity can explain the relatively higher prevalence of MHP and mild PKU phenotypes in Spain compared with NOrthern European populations. We have looked at the geographical distribution in Spain of the more common mutations, finding evidence of local mutation clustering, which could be the result of differences in the ethnic background and/or of genetic drift within each region.

Nonpharmacologic treatment of chronic headache: prediction of outcome.

We studied the ability of headache history, a 4-week headache diary, standard psychological tests, and laboratory measures of psychophysiologic responses to stress to predict the outcome of relaxation therapy and biofeedback for three types of chronic headache. Using canonical discriminant function analyses, each potential predictor set was tested separately, and all four were tested together. Information from the headache history alone correctly classified 89 to 95% of patients as improved or unimproved. No other single predictor set was consistently better than headache history. When all four predictor sets were combined, prediction improved; 93 to 100% of patients were correctly classified.

Acetaminophen: report of an unusual poisoning.

This is a report of an unusual acetaminophen poisoning in a 3-year-old girl who, three days after the ingestion of an estimated thirty-five 325-mg tablets of acetaminophen, had the highest levels of hepatic enzymes ever recorded at Duke Hospital. Although she was only moderately ill with an enlarged liver, she was discharged from the hospital on the seventh day in good condition. The liver enzyme levels returned to normal when last assessed, 50 days after ingestion. The importance of determining acetaminophen plasma concentration at different times to evaluate more precisely the plasma half-life is discussed, along with the current suggested therapy now being recommended for acetaminophen poisoning.