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OBJECTIVE: Human papillomavirus (HPV) is associated with cervical cancer. For the infection to occur, most HPV types depend on interactions with heparan sulfate proteoglycans (HSPGs); however, non-HSPGs receptors are also involved. Laminin 332 is a crucial component of the epidermis’s base membrane. It has shown interactions with HPV that suggest its function as a transient viral receptor in the extracellular matrix (ECM). We provide new information about Laminin 332 and HPV by identifying LAMA3 gene allelic variants from exons 30 and 31 and their distribution among women with and without HPV infection. PATIENTS AND METHODS: We included 192 cervical cancer scrape samples from two groups of patients, 96 samples from patients with a low-grade squamous intraepithelial lesion (LSIL) and 96 samples from HPV-negative samples without LSIL. Identification of the HPV type was performed using an LCD-Array kit. Exons 30 and 31 of LAMA3 were amplified by PCR and analyzed by Sanger’s sequencing. RESULTS: We identified a wide range of HPV types. The most frequent low-risk (lrHPV) HPV types were 6, 42, 44, and 90. For high-risk (hrHPV) HPV were 16, 31, 56, and 66. Only the genetic variant rs1131521 was identified in both groups. However, no significant association was observed between rs1131521 and the study groups. CONCLUSIONS: A single silent polymorphism was identified in both groups with similar frequency, whereas no mutations related to increased epithelial friability were identified. [ABSTRACT FROM AUTHOR]

FisL@bs is a network of remote and virtual laboratories for physics university education via the Internet that offers students the possibility of performing hands-on experiments in different fields of physics in two ways: simulation and real remote operation. This paper gives a detailed account of a novel way in physics in which distance learning students can gain practical experience autonomously. FisL@bs uses the same structure as AutomatL@bs, a network of virtual and remote laboratories for learning/teaching of control engineering, which has been in operation for four years. Students can experiment with the laboratories offered using an Internet connection and a Java-compatible web browser. This paper, specially intended for university educators but easily comprehensible even for undergraduate students, explains how the portal works and the hardware and software tools used to create it. In addition, it also describes two physics experiments already available: spring elasticity and the laws of reflection and refraction. (Contains 8 figures.)

Hemoglobin S is caused by a nucleotide change in HBB gene (HBB:c.20A>T, p.Glu6Val), is presented in diverse forms: simple carriers (HbSA), homozygotes (HbSS) also known as sickle cell anemia, and compound heterozygotes with other β-hemoglobinopathies. It is worldwide distributed, in Mexico, is frequently observed in the southern states Guerrero, Oaxaca and Chiapas. Elevated fetal hemoglobin (HbF) is associated with mild phenotype; single-nucleotide variants (SNVs) in modifier genes, such as BCL11A, HBG2, HBBP1 pseudogene and HBS1L-MYB intergenic region, upregulate HbF synthesis. The aim of this study was to identify HbF regulating genetic variants in HbSS and HbSA Mexican subjects. We studied 39 individuals (HbSS = 24, 61%, HbSA = 15, 39%) from Chiapas (67%) and Guerrero (33%), peripheral blood was collected in ethylenediamine tetraacetic acid (EDTA) for molecular and hematological studies, DNA was isolated by salting-out technic and genotyping was performed through allelic discrimination by real time polymerase chain reaction (RT-PCR) using Taqman® probes for 15 SNV (in BCL11A: rs6706648, rs7557939, rs4671393, rs11886868, rs766432, rs7599488, rs1427407; HBS1L-MYB: rs28384513, rs7776054, rs9399137, rs4895441, rs9402686, rs1320963; HBG2: rs7482144; and HBBP1: rs10128556). The obtained data were analyzed using IMB SPSS v.22.0 software. All minor alleles were observed in frequencies over 0.05, the most frequent was rs9402686 (0.82), while the less frequent was rs101028556 (0.08). In HbSS group, the mean fetal hemoglobin was 11.9 ± 5.9% and was significantly elevated in BCL11A rs11886868 wildtype homozygotes and in carriers of HBS1L-MYB intergenic region rs7776054 (p = 0.04 and p = 0.03, respectively). In conclusion, in HbSS Mexican patients, two SNVs were observed related to increased HbF; BCL11A rs11886868 and HBS1L-MYB rs7776054. [ABSTRACT FROM AUTHOR]

An analysis is performed on the dynamical coupling between the variability of the extratropical stratospheric and tropospheric circulations during the Northern Hemisphere winter. Obtained results provide evidence that in addition to the well-known Charney and Drazin mechanism by which vertical propagation of baroclinic Rossby waves is nonlinearly influenced by the zonal mean zonal wind, topographic forcing constitutes another important mechanism by which nonlinearity is introduced in the troposphere--stratosphere wave-driven coupled variability. On the one hand, vortex variability is forced by baroclinic Rossby wave bursts, with positive (negative) peaks of baroclinic Rossby wave energy occurring during rapid vortex decelerations (accelerations). On the other hand, barotropic Rossby waves of zonal wavenumbers s = 1 and 3 respond to the vortex state, and strong evidence is presented that such a response is mediated by changes of the topographic forcing due to zonal mean zonal wind anomalies progressing downward from the stratosphere. It is shown that wavenumbers s = I and 3 are the dominant Fourier components of the topography in the high-latitude belt where the zonal mean zonal wind anomalies are stronger; moreover, obtained results are in qualitative agreement with the analytical solution provided by the simple topographic wave model of Charney and Eliassen. Finally, evidence is provided that changes of barotropic long (s [less than or equal to] 3) Rossby waves associated with vortex variability reproduce a NAO-like dipole over the Atlantic Ocean but no dipole is formed over the Pacific Ocean. Moreover, results suggest that the nonlinear wave response to topographic forcing may explain the spatial changes of the NAO correlation patterns that have been found in previous studies.

OBJECTIVE: Hunter syndrome, or mucopolysaccharidosis type II (MPS II), is caused by deficiency of the lysosomal enzyme iduronate-2-sulfatase (IDS), which is responsible for degrading heparan and dermatan sulfate. The IDS gene is located on chromosome Xq28; pathological variants in this gene mostly consist of missense mutations and small and larger deletions, which produce different phenotypes. However, there is only one record in our population concerning the molecular mechanism of this disease; a genotype-phenotype description is not available. PATIENTS AND METHODS: There were included 24 unrelated male patients; clinical features were recorded at a database, fluorometric IDS enzyme activity testing was done for each individual, followed by Sanger sequencing to identify mutations. RESULTS: The mutational spectrum was found in 16 out of 24 Mexican patients with MPS II, and its range of phenotypes was described. The most frequent variants were of the missense type. The most affected exons were exon 3 (c.275T>G, c.284_287del, c.325T>C), exon 8 (c.1035G>C, c.550G>A), exon 9 (c.1403G>C, c.1229_1229del), and exon 7 (c.979A>C; this variant has not been previously reported). Exon 5 (c.438C>T, a non-pathogenic variant) was the least frequent. It was also found that the most severely affected patients were those with large deletions (2 out of 24) [rsaIDS: IDSP1 (P164) x0, FMR1, AFF2 (P164)x2] involving genes and pseudogenes. We found 2 patients with a synonymous mutation in exon 4. CONCLUSIONS: O ur r esults c onfirmed r eports in the literature, since the most frequent variants were reported in exons 3 and 8. However, this result varies from one previous report in our population, which mentions large deletions and rearrangements as the most frequent alterations, since complex rearrangements were not found. According to what has been previously found, the most severely affected patients are those in which a whole gene has been deleted. [ABSTRACT FROM AUTHOR]

A study is performed on the energetics of planetary wave forcing associated with the variability of the northern winter polar vortex. The analysis relies on a three-dimensional normal mode expansion of the atmospheric general circulation that allows partitioning the total (i.e., kinetic + available potential) atmospheric energy into the energy associated with Rossby and inertio-gravity modes with barotropic and baroclinic vertical structures. The analysis mainly departs from traditional ones in respect to the wave forcing, which is here assessed in terms of total energy amounts associated with the waves instead of heat and momentum fluxes. Such an approach provides a sounder framework than traditional ones based on Eliassen-Palm (EP) flux diagnostics of wave propagation and related concepts of refractive indices and critical lines, which are strictly valid only in the cases of small-amplitude waves and in the context of the Wentzel-Kramers-Brillouin-Jeffries (WKBJ) approximation. Positive (negative) anomalies of the energy associated with the first two baroclinic modes of the planetary Rossby wave with zonal wavenumber 1 are followed by a downward progression of negative (positive) anomalies of the vortex strength. A signature of the vortex vacillation is also well apparent in the lagged correlation curves between the wave energy and the vortex strength. The analysis of the correlations between individual Rossby modes and the vortex strength further confirmed the result from linear theory that the waves that force the vortex are those associated with the largest zonal and meridional scales. The two composite analyses of displacement- and split-type stratospheric sudden warming (SSW) events have revealed different dynamics. Displacement-type SSWs are forced by positive anomalies of the energy associated with the first two baroclinic modes of planetary Rossby waves with zonal wavenumber 1; split-type SSWs are in turn forced by positive anomalies of the energy associated with the planetary Rossby wave with zonal wavenumber 2, and the barotropic mode appears as the most important component. In respect to stratospheric final warming (SFW) events, obtained results suggest that the wave dynamics is similar to the one in displacement-type SSW events.

Although most children with Hirschsprung disease ultimately achieve functional and comfortable stooling, some will experience a variety of problems after pull-through surgery. The most common problems include soiling, obstructive symptoms, enterocolitis, and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative soiling in children with Hirschsprung disease. The American Pediatric Surgical Association Hirschsprung Disease Interest Group engaged in a literature review and group discussions. Expert consensus was then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with soiling symptoms following pull-through for Hirschsprung disease. Causes of soiling after pull-through are broadly categorized as abnormalities in sensation, abnormalities in sphincter control, and "pseudo-incontinence." A stepwise algorithm for the diagnosis and management of soiling after a pull-through for Hirschsprung disease is presented; it is our hope that this rational approach will facilitate treatment and optimize outcomes. [ABSTRACT FROM AUTHOR]

Hirschsprung disease affects many children every year around the world. Currently, there is an extensive menu of diagnostic methods, and surgical treatments. This situation compels the physicians to follow the rationale of these interventions. The comprehensive diagnosis and treatment of Hirschsprung disease need singular procedures. The clear understanding of how to perform each of these techniques, as well as to read the results is mandatory. Otherwise, the medical team may perform unconscious errors and fall into traps. Many errors still happen in patients with Hirschsprung, resulting in a spectrum of problems; from delayed diagnosis to unnecessary colectomies. In other patients, the damage to the anal canal results in fecal incontinence. When this is established, it is an unreversed and devastating social problem. This article describes why these errors occur and how to prevent them. [ABSTRACT FROM AUTHOR]

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Infertility and reproductive problems have been reported in women with several neurological disorders, for example, demyelination. However, the physiology of such problems has remained unknown so far. The taiep rats are an animal neurological model that initially shows a hypomyelination followed by a progressive demyelination of the central nervous system. This animal has reproductive problems, and the aim of this work is to characterize the follicular development, secretion of ovarian hormones, and presence of noradrenaline in the ovaries of the female taiep rats in the juvenile and adult stages. The taiep rats have low body weight (approximately 19% less than that of SD rats), a delay of 4 days in the age of vaginal opening, and an irregularity in the estrous cycle by the absence or prolongation of some estral cycle stage. In the juvenile stage, we observed a decrease of approximately 44% in the total number of follicles with a 15% increase of atresia and an 80% decrease in the fluorescence intensity of catecholamines in the ovaries, with a 21% increment in plasma concentrations of testosterone. In the adult stage, we observed follicular cysts and a 50% decrease in fluorescence intensity of catecholamines in the ovaries, with changes in the secretion of ovarian hormones, an increase of 20 times in progesterone, and a decrement of a half in estradiol. The demyelination in taiep rats affects follicular development and steroidogenesis in the early stages of the animal’s life, and this is maintained until adulthood. [ABSTRACT FROM AUTHOR]

Introduction Beta-thalassemia (β-thal) is frequent in Mexican patients with microcytosis and hypochromia. We report three novel mutations and analyze the actual mutational spectrum in Mexican population. Methods One hundred and forty-nine β-thal Mexican mestizo patients were studied (154 alleles). ARMS- PCR was performed to identify Cd39C>T, IVS1:1G>A, IVS1:110G>A, -28A>C, initiation codonA>G and IVS1:5G>A mutations, and gap- PCR for δβ-thal Spanish type. DNA sequencing of HBB gene was carried out in negative samples for the initial screening. Results Fifteen different HBB gene mutations were observed in 148 alleles; three of them are novel: -90C>G, 20 bp deletion (at codons 78/85), and IVS2:2T>G; the mutation IVS1:6T>C that was observed for first time in our population; and eleven previously described mutations. Six alleles showed normal HBB sequence. To date, a total of 21 different mutations have been observed in Mexican patients; the four most frequent mutations are of Mediterranean origin: Cd39C>T (37.2%), IVS1:1G>A (17.3%), IVS1:110G>A (13.9%), and δβ-thal Spanish type (9.0%), which represent 77.4% of the total studied alleles. Conclusion Considering the novel mutations -90C>G, -20 bp Cd78/85, IVS2:2T>G and the first observation of IVS1:6T>C, the molecular spectrum of β-thal in Mexicans comprises 21 different mutations, confirming the high allelic heterogeneity in Mexicans. [ABSTRACT FROM AUTHOR]

Introduction Alpha-thalassemia (α-thal) is a common monogenic disorder worldwide. In mixed ethnic populations, α-thal and beta-thalassemia (β-thal) can be expected, sometimes giving complex phenotypes, which without molecular analysis are not easily explained. We performed the molecular identification of α- and β-thal alleles in 51 Mexican patients with microcytosis, hypochromia, and normal or low levels of HbA2. Methods Common deletional alleles (-α3.7, -α4.2, - - SEA, - - MED, - - FIL, - - THAI, -α20.5) and α-triplication were studied by gap- PCR and nondeletional alleles (α IVSI(−5nt), α2NcoI, α1NcoI) by ARMS. β-thal alleles Cd39 (C>T), IVS1:1 (G>A), IVS1:110 (G>A), and Spanish δβ-thal were also investigated. DNA sequencing was performed on HBA2, HBA1, and HBB genes. Negative samples were subjected to MLPA. Results In 35 subjects, we identified the mutations, -α3.7, - - SEA, - - FIL, α IVSI(−5nt), and αααanti3.7 and two novel deletion alleles - -Mex1 (6.8-8.9 kb) and - -Mex2 (77.6-135.7 kb). Four individuals also had a β-thal allele (Cd39/ IVS1:110). No α-thal alleles were observed in 16 subjects, but three had a β-thal mutation Cd39, IVS1:110, and Spanish δβ-thal. Conclusion α-thal is relatively common in Mexican patients, the combination with β-thal is sometimes unexpected, and this underlines the importance of performing molecular analysis for both α- and β-genes defects in patients showing microcytic hypochromic anemia. [ABSTRACT FROM AUTHOR]

LetG=(V, E) be a graph of ordernand letB(D) be the set of vertices inV∖Dthat have a neighbour in the setD. The differential of a setDis defined as ∂ (D)=|B(D)|−|D| and the differential of a graph to equal the maximum value of ∂(D) for any subsetDofV. In this paper we obtain several tight bounds for the differential of strong product graphs. In particular, we investigate the relationship between the differential of this type of product graphs and various parameters in the factors of the product. [ABSTRACT FROM PUBLISHER]

A strengthening of the equatorward temperature gradient in the upper troposphere/lower stratosphere (UTLS), at subtropics and midlatitudes, is consistently reproduced in several modelling studies of the atmospheric response to the increase of greenhouse gas radiative forcing. Some of those studies suggest an increase of the baroclinicity in the UTLS region because of the enhanced meridional temperature gradient. This study presents observational evidence of an increase of the baroclinic wave components of UTLS circulation (UTLS wave baroclinicity), during the second half of the 20th century. The evidence is given by significant positive trends in the energy of baroclinic normal modes of the NCEP/NCAR reanalysis, and significant positive trends in the UTLS eddy available potential energy of the NCEP/NCAR, ERA-40, NCEP-2 and JRA-25 reanalyses. Significant positive trends in the frequency of double tropopause events in radiosonde data are also interpreted as a manifestation of an increase of the UTLS wave baroclinicity. [ABSTRACT FROM AUTHOR]

Abstract: It has been demonstrated that the spatial structure of the Northern Annular Mode depends on external forcings such as solar activity. In some cases, this variations lead to a spatial pattern very similar to that of the so-called North Atlantic Oscillation. In this work, we use relative angular momentum, trying to provide more information about this solar effects and how they affect this variability pattern. An analysis about a possible modulation of the QBO is also included. [Copyright &y& Elsevier]

UNEDLabs is a web portal based on a free, modern, open source, and well-known learning management system: Moodle. This portal joins two theme networks of virtual and remote laboratories (one for Control Engineering and another one for Physics, named AutomatL@bs and FisL@bs, respectively) together. AutomatL@bs has been operative for five years now. Following AutomatL@bs' scheme, FisL@bs was created as a network of remote and virtual laboratories for physics university education via the Internet to offer students the possibility of performing hands-on experiences in different fields of physics in two ways: simulation and real remote operation. Now, both FisL@bs and AutomatL@bs join together (while maintaining their independency) into an unique new web portal called UNEDLabs. This work focuses on this new web environment and gives a detailed account of a novel way in Physics to let distance learning students gain practical experience autonomously. This paper explains how the new portal works and the software tools used for creating it. In addition, it also describes the physics experiments which are already operative. [ABSTRACT FROM AUTHOR]