Directional control of charge and valley currents in a graphene-based device.

We propose a directional switching effect in a metallic device. To this end we exploit a graphene-based device with a three-terminal geometry in the presence of a magnetic field. We show that unidirectional charge and valley currents can be controlled by the Fermi energy and the magnetic field direction in the active device. Interestingly, unidirectional transport of charges and valleys is generated between two-terminals at the same bias voltage. Furthermore, we quantify the valley depolarization as a function of disorder concentration. Our results open a way for active graphene-based valleytronics devices.

Fingerprints of a position-dependent Fermi velocity on scanning tunnelling spectra of strained graphene.

Nonuniform strain in graphene induces a position dependence of the Fermi velocity, as recently demonstrated by scanning tunnelling spectroscopy experiments. In this work, we study the effects of a position-dependent Fermi velocity on the local density of states (LDOS) of strained graphene, with and without the presence of a uniform magnetic field. The variation of LDOS obtained from tight-binding calculations is successfully explained by analytical expressions derived within the Dirac approach. These expressions also rectify a rough Fermi velocity substitution used in the literature that neglects the strain-induced anisotropy. The reported analytical results could be useful for understanding the nonuniform strain effects on scanning tunnelling spectra of graphene, as well as when it is exposed to an external magnetic field.

Immune response of toddlers with history of prematurity.

BACKGROUND: It is not quite well established how immune responses differ in term and preterm infants beyond the first year of life. This study aimed to evaluate aspects of the innate and adaptive immune responses in a group of preterm infants in comparison with their term peers. METHODS: In this cross-sectional study peripheral blood mononuclear cells (PBMC) were isolated from preterm and term children at age three years. Innate immune response was evaluated by the analysis of TLR receptors expression on CD11c+HLADRhigh cells and inflammatory cytokine production after PBMC stimulation with Toll like receptors (TLR) ligands. Adaptive immune response was evaluated by T cells' phenotyping and function after stimulation with polyclonal conventional T cell stimulus. CONCLUSION: We have found that the patterns of innate and adaptive immune responses at 3 years of age were not affected by the fact of the children having being born preterm or at term.

IL-8/IL-17 gene variations and the susceptibility to severe viral bronchiolitis.

Clinical manifestations of acute bronchiolitis (AB) vary from minimal disease to severe respiratory failure. The response to respiratory viral infections is possibly influenced by genetic polymorphisms linked to the regulation of the inflammatory response. In the present study, we investigated whether interleukin-8 (IL-8) and interleukin-17 (IL-17) genetic variants are associated with the severity of AB. A group of Brazilian infants hospitalized with AB and a control group (infants with no or mild AB, without hospitalization) were genotyped for four IL-8/IL-17 variations. For replication, we studied an Argentinean population sample of infants with mild and severe AB. IL-8 polymorphism (rs 2227543) and IL-17 (rs2275913) variants showed significant associations with the severity of AB. The effect of the IL-8 variation could be replicated in the Argentinean sample. This finding suggests that IL-8 variations may influence the severity of AB in young infants. Further genetic association studies in low- or middle-income populations are necessary with the aim of expanding knowledge in this area.

Examining pregnancy-specific smartphone applications: what are patients being told?

OBJECTIVE: The objective of this study is to evaluate the informative content of two free, pregnancy-specific smartphone applications and their accuracy and adherence to prenatal care guidelines. STUDY DESIGN: This is a qualitative analysis of the information delivered through two free, pregnancy-specific smartphone applications (apps): Text4Baby (T4B) and Baby Center's 'My Pregnancy Today' (BC). All information from conception through 2 weeks postpartum were transcribed and coded independently by two physician researchers. Content was analyzed and assigned thematic codes. The proportion of content each app delivered per theme was then calculated and the χ(2)-test was used to compare thematic frequency between apps. RESULTS: A total of 609 pieces of daily content were transcribed; 698 message themes were coded and analyzed. Most information delivered by T4B was about fetal development (23.8%) or prenatal care (16.6%); most content from BC was about normal pregnancy symptoms (20.1%) or maternal well-being (21.1%); the differences between apps for each of these themes were statistically significant (P<0.05). A total of four messages contained incomplete or ambiguous content; neither app delivered overtly incorrect medical information. T4B and BC had a similar proportion of information that was in-line with the American College of Obstetrics and Gynecology Guidelines for Prenatal Care. Neither app delivered any messages about contraception. CONCLUSION: T4B and BC are free, pregnancy-specific apps with different focuses. Neither app delivers comprehensive prenatal information, as evidenced by the absence of information about postpartum contraception. More information is needed to determine the role of such apps in prenatal care.

l-Theanine prevents carbon tetrachloride-induced liver fibrosis via inhibition of nuclear factor κB and down-regulation of transforming growth factor ß and connective tissue growth factor.

Here we evaluated the ability of L-theanine in preventing experimental hepatic cirrhosis and investigated the roles of nuclear factor-κB (NF-κB) activation as well as transforming growth factor ß (TGF-ß) and connective tissue growth factor (CTGF) regulation. Experimental hepatic cirrhosis was established by the administration of carbon tetrachloride (CCl4) to rats (0.4 g/kg, intraperitoneally, three times per week, for 8 weeks), and at the same time, adding L-theanine (8.0 mg/kg) to the drinking water. Rats had ad libitum access to water and food throughout the treatment period. CCl4 treatment promoted NF-κB activation and increased the expression of both TGF-ß and CTGF. CCl4 increased the serum activities of alanine aminotransferase and γ-glutamyl transpeptidase and the degree of lipid peroxidation, and it also induced a decrease in the glutathione and glutathione disulfide ratio. L-Theanine prevented increased expression of NF-κB and down-regulated the pro-inflammatory (interleukin (IL)-1ß and IL-6) and profibrotic (TGF-ß and CTGF) cytokines. Furthermore, the levels of messenger RNA encoding these proteins decreased in agreement with the expression levels. L-Theanine promoted the expression of the anti-inflammatory cytokine IL-10 and the fibrolytic enzyme metalloproteinase-13. Liver hydroxyproline contents and histopathological analysis demonstrated the anti-fibrotic effect of l-theanine. In conclusion, L-theanine prevents CCl4-induced experimental hepatic cirrhosis in rats by blocking the main pro-inflammatory and pro-fibrogenic signals.

U-500R and aspart insulin for the treatment of severe insulin resistance in pregnancy associated with pregestational diabetes.

Severe insulin resistance as a complication of diabetes in pregnancy is seen with increasing frequency. Treatment with large doses of insulin (>300 units perday) can be practically difficult. A woman with preexisting Type 2 diabetes mellitus and poor glycemic control presented in early pregnancy requiring over 1000 units of insulin daily. She was transitioned to subcutaneous U-500 (concentrated regular insulin) in combination with a rapid-acting insulin analog achieving good glycemic control and good maternal and fetal outcomes. U-500R insulin in conjunction with a rapid-acting insulin analog can be used safely in early pregnancy to improve glycemic control in severe insulin resistance due to pregestational diabetes.

Critical wavefunctions in disordered graphene.

In order to elucidate the presence of non-localized states in doped graphene, a scaling analysis of the wavefunction moments, known as inverse participation ratios, is performed. The model used is a tight-binding Hamiltonian considering nearest and next-nearest neighbors with random substitutional impurities. Our findings indicate the presence of non-normalizable wavefunctions that follow a critical (power-law) decay, which show a behavior intermediate between those of metals and insulators. The power-law exponent distribution is robust against the inclusion of next-nearest neighbors and growing the system size.

Doped graphene: the interplay between localization and frustration due to the underlying triangular symmetry.

An intuitive explanation of the increase in localization observed near the Dirac point in doped graphene is presented. To do this, we renormalize the tight binding Hamiltonians in such a way that the honeycomb lattice maps into a triangular one. Then, we investigate the frustration effects that emerge in this Hamiltonian. In this doped triangular lattice, the eigenstates have a bonding and antibonding contribution near the Dirac point, and thus there is a kind of Lifshitz tail. The increase in frustration is related to an increase in localization, since the number of frustrated bonds decreases with disorder, while the frustration contribution raises.

Chilean women's preferences regarding mode of delivery: which do they prefer and why?

OBJECTIVE: Caesarean section rates in Chile are reported to be as high as 60% in some populations. The purpose of this study was to determine pregnant Chilean women's preferences towards mode of delivery. DESIGN: Interviewer-administered cross-sectional survey. SETTING: Prenatal clinics in Santiago, Chile. Population Pregnant women in Santiago, Chile. METHODS: Of 180 women completing the questionnaire, 90 were interviewed at a private clinic (caesarean delivery rate 60%) and 90 were interviewed at a public clinic (cesarean delivery rate 22%). Data collected included demographics, preferred mode of delivery, and women's attitudes towards vaginal and caesarean deliveries. MAIN OUTCOME MEASURES: Mode of delivery preferences, perceptions of mode of delivery measured on a 1-7 Likert scale. RESULTS: The majority of women (77.8%) preferred vaginal delivery, 9.4% preferred caesarean section, and 12.8% had no preference. There was no statistical difference in preference between the public clinic (11% preferred caesarean) and the private clinic (8% preferred caesarean, P= 0.74). Overall, women preferring caesarean birth were slightly older than other groups (31.6 years, versus 28.4 years for women who preferred vaginal and 27.3 years for women who had no preference, P= 0.05), but there were otherwise no differences in parity, income, or education. On a scale of 1-7, women preferring caesarean birth rated vaginal birth as more painful, while women preferring vaginal birth rated it as less painful (5.8 versus 3.7, P= 0.003). Whether vaginal or caesarean, each group felt that their preferred mode of delivery was safer for their baby (P < 0.001). CONCLUSIONS: Chilean women do not prefer caesarean section to vaginal delivery, even in a practice setting where caesarean delivery is more prevalent. Thus, women's preferences is unlikely to be the most significant factor driving the high caesarean rates in Chile.

Phase I trial of the antifolate ZD9331 in combination with cisplatin in patients with refractory solid malignancies.

PURPOSE: To determine the maximum tolerated dose and dose-limiting toxicities (DLTs) of ZD9331 in combination with cisplatin in patients with refractory solid tumors and to describe any preliminary antitumor activity associated with this regimen. MATERIALS AND METHODS: Patients received combination therapy with ZD9331 as a 30-min infusion on days 1 and 8 of a 21-day cycle at doses of 100 or 130 mg/m(2), followed by cisplatin at 50 or 75 mg/m(2) as a 30- to 60-min infusion on day 1 only. RESULTS: A total of 16 patients received 59 cycles of ZD9331 and cisplatin. Patients were enrolled at three dose levels: ZD9331/cisplatin 100/50 ( n=3), 130/50 ( n=9), 130/75 ( n=4). DLTs at 130/75 included thrombocytopenia, neutropenia, fatigue, nausea, vomiting and stomatitis. Among 15 evaluable patients, 2 showed a partial response (patients with mesothelioma and head and neck cancer) and 6 showed stable disease (for a median of 5.5 cycles). CONCLUSIONS: ZD9331 in combination with cisplatin was well tolerated at a dose of 130/50 mg/m(2) after establishing the principal DLTs of neutropenia and thrombocytopenia. The combination shows evidence of antitumor activity in a pretreated population.

Reproductive fitness in maternal homocystinuria due to cystathionine beta-synthase deficiency.

Early diagnosis and improved treatment are leading to the potential for increased reproductive capability in homocystinuria due to cystathionine beta-synthase (CbetaS) deficiency, but information about reproductive outcome and risk of thromboembolism in pregnancy is limited. To provide further information, clinical and biochemical information was obtained on women with maternal homocystinuria, on their pregnancies and on the offspring. This information included blood sulphur amino acids and total homocysteine, CbetaS gene mutations and developmental and cognitive scores in the offspring. The study involved 15 pregnancies in 11 women, of whom 5 were pyridoxine-nonresponsive and 6 were pyridoxine-responsive. Complications of pregnancy included pre-eclampsia at term in two pregnancies and superficial venous thrombosis of the leg in a third pregnancy. One pregnancy was terminated and two pregnancies resulted in first-trimester spontaneous abortions. The remaining 12 pregnancies produced live-born infants with normal or above-normal birth measurements. One offspring has multiple congenital anomalies that include colobomas of the iris and choroid, neural tube defect and undescended testes. He is also mentally retarded and autistic. A second offspring has Beckwith-Wiedemann syndrome. The remaining 10 offspring were normal at birth and have remained normal. There was no relationship between the severity of the biochemical abnormalities or the therapies during pregnancy to either the pregnancy complications or the offspring outcomes. The infrequent occurrences of pregnancy complications, offspring abnormalities and maternal thromboembolic events in this series suggest that pregnancy and outcome in maternal homocystinuria are usually normal. Nevertheless, a cautious approach would include careful monitoring of these pregnancies with attention to metabolic therapy and possibly anticoagulation.

Congenital microcephaly: phenotypic features in a consecutive sample of newborn infants.

OBJECTIVE: We compared the prevalence of major and minor anomalies in a consecutive sample of newborn infants with congenital microcephaly with that among normocephalic infants. STUDY DESIGN: Head measurements from >19,000 liveborn infants at 1 hospital during the years 1991 and 1992 were reviewed. Infants whose head circumference was in the lowest quartile (n = 850) were remeasured by research assistants to identify all whose head circumference was 2 SD below the mean for gestational age; 106 infants with congenital microcephaly were identified. Infants with microcephaly (n = 65) and 294 infants in a control group were examined systematically for major malformations and minor physical features. RESULTS: Four (6.2%) of the 65 infants examined either had a major malformation or were considered dysmorphic. One of the 4 had a specific multiple malformation syndrome, and 1 dysmorphic infant had a rare metabolic defect. Overall, the infants with microcephaly did not have a higher frequency of minor anomalies. However, there was a higher frequency of frontal bossing, small chin, and short nose with anteverted nares, which was associated with small body size rather than microcephaly. CONCLUSIONS: Congenital microcephaly is infrequently accompanied by major malformations and occurs rarely as part of a recognizable syndrome.

Discordant phenotype in monozygotic twins with Fryns syndrome.

We report on a pair of monozygotic twins with Fryns syndrome discordant for severity of diaphragmatic defect. Both twins had macrocephaly, "coarse" facial appearance, hypoplasia of distal phalanges, and an extra pair of ribs. Twin A lacked an apparent diaphragmatic defect, and at 1 year of age had mild developmental delay. Twin B had a left congenital diaphragmatic hernia and died neonatally. Absence of diaphragmatic defect in Fryns syndrome may represent a subpopulation of more mildly affected patients whose developmental outcome is currently undetermined.

Maternal gamma-cystathionase deficiency: absence of both teratogenic effects and pregnancy complications.

gamma-Cystathionase deficiency (cystathioninemia-cystathioninuria) is a disorder of the transsulfuration pathway characterized by the accumulation of cystathionine in blood and urine. There are probably no clinical consequences. However, maternal gamma-cystathionase deficiency has not been reported. We studied 2 pregnancies and the offspring of these pregnancies in a woman with the pyridoxine-nonresponsive form of the disorder. The outcomes were favorable, suggesting that maternal gamma-cystathionase deficiency may not be deleterious to the pregnant woman or the fetus.

El Síndrome de interrupción de los inhibidores selectivos de la recaptación de serotonina / The discontinuation syndrome of selective serotonin reuptake inhibitors

Los pacientes que suspenden las medicaciones (antidepresivos, estabilizadores del afecto o antipsicóticos) presentam con frecuencia síntomas y cognoscitivos que pueden, en algunos casos, como sucede con los IMAOS clásicos, requerir tratamiento intrahospitalario. La sintomatología es inespecífica y difiere de los síntomas secundarios indeseables del fármaco o del síndrome de abstinencia que se apresenta con hipnóticos, barbitúricos, benzodiacepinas, alcohol o sub tancias adictivas. En el presente trabajo se hace una revisión de la literarura sobre los aspectos clínicos, epidemiológicos y terapéuticos del Síndrome de Interrupción del tratamiento con los inhibidores selectivos de la recaptación de serotonina (SRS)

[Periovular: valid method for no viable pregnancy in the 1st-2nd trimester]. / Periovular: méthod válido para la interrupción del embarazo no viable de 2o-3er trimestre.

Isotonic solution was administered extraamniotically to 41 pregnant patients with dead fetus of 24 to 40 weeks of gestational age. Vaginal deliveries occurred in 90% and 9,7% had complications.

[Premature rupture of fetal membranes in the midtrimester (II): Antibiotic treatment in a case of intraamniotic infection prior to fetal viability]. / Rotura prematura de membranas en el trimestre medio (II): Tratamiento antibiótico en un caso de infección intra-amniótica previo a la viabilidad fetal.

A case of a 33 year old woman G7P6A1, with preterm premature rupture of membranes at 20 weeks of gestation and asymptomatic intramniotic infection is reported. At admission, the presence of Klebsiella oxytoca in amniotic fluid was demonstrated by amniocentesis. Parenteral antibiotics were administered with a following demonstration of aseptic fluid. The patient delivered at 29 1/2 weeks of pregnancy. A newborn weighing 1520 with an Apgar score of 8-8 was obtained. The mother had a normal puerperal period without any evidence of infectious morbidity. A clinical sepsis was demonstrated in the newborn with appropriate response to antibiotic therapy. No further complications were observed.

[Borderline tumors of the ovary. Laparoscopic management?]. / Tumores borderline de ovario. Manejo laparoscópico?

Two cases of epithelial ovarian tumors of borderline malignancy initially approached by laparoscopy are presented. The role of laparoscopy are presented. The role of laparoscopy in the management of ovarian tumors is discussed.