Hexagonal boron nitride exfoliation and dispersion.

Research on hexagonal boron nitride (hBN) 2-dimensional nanostructures has gained traction due to their unique chemical, thermal, and electronic properties. However, to make use of these exceptional properties and fabricate macroscopic materials, hBN often needs to be exfoliated and dispersed in a solvent. In this review, we provide an overview of the many different methods that have been used for dispersing hBN. The approaches that will be covered in this review include solvents, covalent functionalization, acids and bases, surfactants and polymers, biomolecules, intercalating agents, and thermal expansion. The properties of the exfoliated sheets obtained and the dispersions are discussed, and an overview of the work in the field throughout the years is provided.

Liquid crystals of neat boron nitride nanotubes and their assembly into ordered macroscopic materials.

Boron nitride nanotubes (BNNTs) have attracted attention for their predicted extraordinary properties; yet, challenges in synthesis and processing have stifled progress on macroscopic materials. Recent advances have led to the production of highly pure BNNTs. Here we report that neat BNNTs dissolve in chlorosulfonic acid (CSA) and form birefringent liquid crystal domains at concentrations above 170 ppmw. These tactoidal domains merge into millimeter-sized regions upon light sonication in capillaries. Cryogenic electron microscopy directly shows nematic alignment of BNNTs in solution. BNNT liquid crystals can be processed into aligned films and extruded into neat BNNT fibers. This study of nematic liquid crystals of BNNTs demonstrates their ability to form macroscopic materials to be used in high-performance applications.

A Pooled Case-only Analysis of Reproductive Risk Factors and Breast Cancer Subtype Among Black Women in the Southeastern United States.

BACKGROUND: We investigated the association between reproductive risk factors and breast cancer subtype in Black women. On the basis of the previous literature, we hypothesized that the relative prevalence of specific breast cancer subtypes might differ according to reproductive factors. METHODS: We conducted a pooled analysis of 2,188 (591 premenopausal, 1,597 postmenopausal) Black women with a primary diagnosis of breast cancer from four studies in the southeastern United States. Breast cancers were classified by clinical subtype. Case-only polytomous logistic regression models were used to estimate ORs and 95% confidence intervals (CI) for HER2+ and triple-negative breast cancer (TNBC) status in relation to estrogen receptor-positive (ER+)/HER2- status (referent) for reproductive risk factors. RESULTS: Relative to women who had ER+/HER2- tumors, women who were age 19-24 years at first birth (OR, 1.78; 95% CI, 1.22-2.59) were more likely to have TNBC. Parous women were less likely to be diagnosed with HER2+ breast cancer and more likely to be diagnosed with TNBC relative to ER+/HER2- breast cancer. Postmenopausal parous women who breastfed were less likely to have TNBC [OR, 0.65 (95% CI, 0.43-0.99)]. CONCLUSIONS: This large pooled study of Black women with breast cancer revealed etiologic heterogeneity among breast cancer subtypes. IMPACT: Black parous women who do not breastfeed are more likely to be diagnosed with TNBC, which has a worse prognosis, than with ER+/HER2- breast cancer.

Encapsulation of curcumin into layered double hydroxides improve their anticancer and antiparasitic activity.

OBJECTIVES: Curcumin (CUR) has well-known activity against cancer cells and parasites; however, its applications are limited since this is an unstable molecule, which may suffer degradation by light and temperature, also, the low water solubility reduce its bioavailability. Layered double hydroxides (LDH) are well-known materials owing to the excellent anion exchange capacity, good biocompatibility and low toxicity. METHODS: Layered double hydroxides nanoparticles prepared with zinc and magnesium cations were used as a vehicle for CUR in Caco-2, Giardia lamblia and Entamoeba histolytica cultures. The physicochemical properties of Mg-LDH-CUR and Zn-LDH-CUR were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR) and X-ray powder diffraction (XRD). Additionally, the load efficiency, release profiles and photostability of CUR were quantified by high-performance liquid chromatography (HPLC) and UV-Vis spectrometry. Then, Mg-LDH-CUR and Zn-LDH-CUR were tested on Caco-2, G. lamblia and E. histolytica cultures. KEY FINDINGS: The experiments demonstrated that Zn-LDH-CUR protects better against photodegradation by UV light, while Mg-LDH-CUR showed increased toxicity against Caco-2 cell, G. lamblia and E. histolytica, in comparison with free CUR. CONCLUSIONS: Layered double hydroxides are good vehicles to improve stability, resistance to degradation of CUR, also they are useful to improve solubility, provide a controlled release and improve the cytotoxic activity. Additionally, it was shown that the composition of the M+2 cation of LDH affects its properties and structure and that this directly influences its biological activity. The findings are important to select the composition of the encapsulation vehicle for a specific activity.

SOCIOEMOTIONAL AND BEHAVIORAL PROBLEMS IN TODDLERS WITH LANGUAGE DELAY.

Toddlers with language delay are at risk for persistent developmental and behavioral difficulties; however, the association between socioemotional/behavior problems and language in young children is not well understood. This study explored socioemotional/behavior problems in a unique sample of toddlers with language delays using a measure developed explicitly for this age group. Toddlers identified by 18 months with receptive and expressive language delay (LD; n = 30) or typical development (TD; n = 61) were evaluated at 18 and 24 months of age using the Infant-Toddler Social and Emotional Assessment (ITSEA) and the Mullen Scales of Early Learning. Compared to toddlers who had TD, toddlers with LD had significantly more concerning scores at 18 and 24 months on all ITSEA domains. The rate of "clinical concern" on most domains was not high in either group, except that >60% of LD toddlers were in the clinical concern range on the Competence domain. Socioemotional/behavioral problems were dimensionally related to receptive and expressive language, with greater language delay associated with more concerning ITSEA scores. Socioemotional and behavioral problems are related to receptive and expressive language abilities in 18- and 24-month-olds, indicating the need for screening of both types of concerns in toddlers identified with potential language delays.

Co-Amorphous Simvastatin-Nifedipine with Enhanced Solubility for Possible Use in Combination Therapy of Hypertension and Hypercholesterolemia.

The high index of simultaneous incidence of hypertension and hypercholesterolemia in the population of many countries demands the preparation of more efficient drugs. Therefore, there is a significant area of opportunity to provide as many alternatives as possible to treat these illnesses. Taking advantage of the solubility enhancement that can be achieved when an active pharmaceutical ingredient (API) is obtained and stabilized in its amorphous state, in the present work, new drug-drug co-amorphous formulations (Simvastatin SIM- Nifedipine NIF) with enhanced solubility and stability were prepared and characterized. Results show that the co-amorphous system (molar ratio 1:1) is more soluble than the pure commercial APIs studied separately. Aqueous dissolution profiles showed increments of solubility of 3.7 and 1.7 times for SIM and NIF, correspondingly, in the co-amorphous system. The new co-amorphous formulations, monitored in time, (molar fractions 0.3, 0.5 and 0.7 of SIM) remained stable in the amorphous state for more than one year when stored at room temperature and did not show any signs of crystallization when re-heating. Inspection on the remainder of a sample after six hours of dissolution showed no recrystallization, confirming the stability of co-amorphous system. The enhanced solubility of the co-amorphous formulations makes them promising for simultaneously targeting of hypertension and hypercholesterolemia through combination therapy.

Cost-effective smartphone-based reconfigurable electrochemical instrument for alcohol determination in whole blood samples.

The determination of ethanol intoxication in whole blood samples may open the opportunity for a precise and quick point-of-measurement in the ambit of medical emergency or law enforcement. In contrast with traditional techniques based on breath sampling, direct blood measurements present greater immunity to errors specially in case of unconscious or non-collaborative patients. In this context, a portable, sensitive and easy-to-use instrument is highly desirable. In the current work we present a smartphone-based µPotentiostat which combines a novel circuital technique for sensor readout digitalization with a reusable lab-on-a-chip (LoC) concept. Such system allows both chronoamperometric and cyclic voltammetry measurements with a reduced number of electronic components on a very compact PCB (38.5â€¯× 22.5 mm2). Power, data-link and user interface are provided in combination with a standard smartphone, enabling cost-effectiveness and reconfigurability without sacrificing precision. The readout platform discussed in this work has been coupled to a LoC for point-of-care combining Pt electrodes microfabricated on silicon substrate for electrochemical measurement and a microfluidic structure of methacrylate for fluid management. Biosensing is enabled by in situ electrodeposition of a calcium alginate hydrogel containing horseradish peroxidase (HPR) and alcohol oxidase (AOx) for selective ethanol detection. Alginate membrane electrodeposition has been here optimized for rapid generation (2 min) and to retain the cellular fraction, thus allowing the measurement in whole blood samples. The µPotentiostat features a sensitivity of 36 nA/g L-1 to ethanol concentration in blood in the 0-1.25 g;L-1 range, with a limit of quantification (LoQ) of 4.5 nA, which is a suitable response for discerning the legal, illegal, severely illegal thresholds in a 40 µL sample of blood.

Ndufs4 related Leigh syndrome: A case report and review of the literature.

The genetic causes of Leigh syndrome are heterogeneous, with a poor correlation between the phenotype and genotype. Here, we present a patient with an NDUFS4 mutation to expand the clinical and biochemical spectrum of the disease. A combined defect in the CoQ, PDH and RCC activities in our patient was due to an inappropriate assembly of the RCC complex I (CI), which was confirmed using Blue-Native polyacrylamide gel electrophoresis (BN-PAGE) analysis. Targeted exome sequencing analysis allowed for the genetic diagnosis of this patient. We reviewed 198 patients with 24 different genetic defects causing RCC I deficiency and compared them to 22 NDUFS4 patients. We concluded that NDUFS4-related Leigh syndrome is invariably linked to an early onset severe phenotype that results in early death. Some data, including the clinical phenotype, neuroimaging and biochemical findings, can guide the genetic study in patients with RCC I deficiency.

Erythrocyte Catalase Activity in More Frequent Microcytic Hypochromic Anemia: Beta-Thalassemia Trait and Iron Deficiency Anemia.

Most common microcytic hypochromic anemias are iron deficiency anemia (IDA) and ß-thalassemia trait (BTT), in which oxidative stress (OxS) has an essential role. Catalase causes detoxification of H2O2 in cells, and it is an indispensable antioxidant enzyme. The study was designed to measure erythrocyte catalase activity (ECAT) in patients with IDA (10) or BTT (21), to relate it with thalassemia mutation type (ß (0) or ß (+)) and to compare it with normal subjects (67). Ninety-eight individuals were analyzed since September 2013 to June 2014 in Tucumán, Argentina. Total blood count, hemoglobin electrophoresis at alkaline pH, HbA2, catalase, and iron status were performed. ß-thalassemic mutations were determined by real-time PCR. Normal range for ECAT was 70,0-130,0 MU/L. ECAT was increased in 14% (3/21) of BTT subjects and decreased in 40% (4/10) of those with IDA. No significant difference (p = 0,245) was shown between normal and BTT groups, while between IDA and normal groups the difference was proved to be significant (p = 0,000). In ß (0) and ß (+) groups, no significant difference (p = 0,359) was observed. An altered ECAT was detected in IDA and BTT. These results will help to clarify how the catalase activity works in these anemia types.

Molecular characterization and phenotypical study of ß-thalassemia in Tucumán, Argentina.

The main hereditary hemoglobin (Hb) disorder in Argentina is ß-thalassemia (ß-thal). Molecular studies performed in the center of the country exhibited a marked prevalence of the codon 39 (C > T) and IVS-I-110 (G > A) mutations. The northwest region of Argentina has a different demographic history characterized by an important Spanish influx. Seventy-one ß-thal carriers attending the Instituto de Bioquímica Aplicada, Tucumán, Argentina, were investigated for ß-globin gene mutations by real-time polymerase chain reaction (RT-PCR). To examine the genotype-phenotype relationship, mean corpuscular volume (MCV), mean corpuscular Hb (MCH) and Hb A2 were measured. In order to recognize ß-thal, Mentzer Index, Shine & Lal and Red Cell Distribution Width Index (RDWI), were calculated. The ethnic background of subjects revealed that 82.0% of the population was of Italian, Spanish and Arab origin. Seven mutations were detected: codon 39 (45.0%), IVS-I-1 (G > A) (22.5%), IVS-I-110 (16.3%), IVS-II-1 (G > A) (4.1%), IVS-I-1 (G > T) (2.0%), IVS-I-6 (T > C) (2.0%) and IVS-II-745 (G > C) (2.0%). In three families (6.1%), ß-thal mutations were not determined. These results differed from other Argentinian studies because at present codon 39 and IVS-I-1 are the most prevalent; MCV, MCH and Hb A2 did not correlate with the type of mutation (ß(0)/ß(+)). Values of MCV (67.0 fL) and Hb A2 (4.85%) were unable to discriminate between them. Significant differences (p < 0.05) in MCV, MCH and Shine & Lal were observed between the undetermined group and the three most common mutations. These data show different patterns of ß-thal mutations in the center and northwest regions of Argentina. Differences might represent the influence of Spanish immigration.

Resistencia osmótica eritrocitaria en el diagnóstico de anemias hereditarias en Tucumán, Argentina / Red cell osmotic resistance in the hereditary anemias diagnosis in Tucumán, Argentina / Resistência osmótica eritrocitária no diagnóstico de anemias hereditárias em Tucumán, Argentina

Las anemias hereditarias más frecuentes en Tucumán (Argentina) son el rasgo beta talasémico (RBT), las hemoglobinopatías estructurales (HBP) y la esferocitosis hereditaria (EH). La resistencia osmótica eritrocitaria inmediata y 24 horas post-incubación constituye el método diagnóstico de la EH, y como tubo único (ROETU) es usada para cribado de RBT. El propósito del trabajo fue determinar el comportamiento de ROETU (4,0 y 5,5 g/L de NaCl) en el diagnóstico de anemias hereditarias. Se estudiaron 125 pacientes: 34 normales (GN), 59 con RBT (GRBT), 21 con HBP (GHBP) y 11 con EH (GEH), que fueron agrupados en niños (≤12 años), mujeres y hombres (>12 años). Se realizaron hemograma (Coulter AcT10 y Sysmex KX-21N), índices de Mentzer y de Shine&Lal, ROETU, hierro, transferrina y saturación de transferrina (Wiener Lab), reticulocitos (azul brillante de cresilo), prueba de falciformación y electroforesis de hemoglobina a pH alcalino y ácido. GRBT presentó anemia microcítica hipocrómica, y GEH y GHBP, anemia normocítica normocrómica. El hierro fue normal. GRBT y GHBP fueron resistentes en ROETU 4,0 g/L, aunque GRBT mostró mayor resistencia (p<0,05). GEH fue menos resistente que GN en ROETU 5,5 g/L (p<0,05). ROETU 4,0 y 5,5 g/L serían recomendables en el diagnóstico presuntivo de RBT y EH, respectivamente.

Beta thalassaemia trait (BTT), structural hemoglobinopathies (SHB) and hereditary spherocytosis (HS) are the most frequent hereditary anaemias in Tucumán (Argentina). Immediately and 24 hours post-incubation red cell osmotic resistance is the diagnosis method of HS, and as a single tube (RORST), it is used for clínicamenBTT screening. The purpose of this study was to determine the RORST (NaCl 4.0 and 5.5 g/L) behaviour in the diagnosis of hereditary anemia. The study encompassed 125 patients : 34 normal patients (NG), 59 with BTT (BTTG), 21 with SHB (SHBG) and 11 with HS (HSG), who were divided into children (≤12 years), women and men (> 12 years). Blood count (Coulter AcT10 and Sysmex KX-21N), Mentzer and Shine&Lal indexes, RORST, iron, transferrin and transferrin saturation (Wiener Lab), reticulocytes (brilliant cresyl blue), sickling and hemoglobin electrophoresis at alkaline and acid pH were performed. BTTG showed hypochromic microcytic anemia, and SHBG and HSG, normochromic normocytic anemia. Iron was normal. BTTG and SHBG were resistant in RORST 4.0 g/L, but BTTG showed more resistance (p<0.05). SHG was less resistant than NG at RORST 5.5 g/L (p<0.05). RORST at values of 4.0 and 5.5 g/L would be recommended for the presumptive diagnosis of BTT and SH, respectively.

As anemias hereditárias mais comuns em Tucumán (Argentina) são o traço beta talassemia minor (BTM), as hemoglobinopatias estruturais (HBP) e esferocitose hereditária (EH). A resistência osmótica dos eritrócitos imediata e 24 horas pós-incubação é o método de diagnóstico da EH, e como um único tubo (ROETU) é usado para a detecção de BTM. O objectivo deste estudo foi determinar o comportamento de ROETU (4,0 e 5,5 g/L de NaCl) para o diagnóstico de anemias hereditárias. Foram estudados 125 pacientes: 34 normais (GN), 59 com BTM (GBTM), 21 com HBP (GHBP) e 11 com EH (GEH), que foram reunidos em crianças (≤12 anos), mulheres e homens (>12 anos). Foi realizado hemograma (Coulter AcT10 e Sysmex KX-21N), índices de Mentzer e Shine&Lal, ROETU, ferro, transferrina e saturação de transferrina (Wiener Lab), reticulócitos (azul de cresil brilhante), teste de falcização e eletroforese de hemoglobina em pH alcalino e ácido. GBTM mostrou anemia microcítica hipocrômica, e GEH e GHBP, anemia normocítica normocrômica. O ferro foi normal. GRBT e GHBP foram resistentes em ROETU 4,0 g/L, mas GBTM mostrou maior resistência (p<0,05). GEH foi menos resistente que GN em ROETU 5,5 g/L (p<0,05). ROETU 4,0 e 5,5 g/L seria recomendado para o diagnóstico presuntivo da BTM e EH, respectivamente.

Alteraciones bucodentales en niños con insuficiencia renal crónica y transplante renales / Oral disorders in children with chronic renal failure and renal transplant

El propósito de este trabajo es determinar las manifestaciones bucodentales en niños con insuficiencia renal crónica y/o transplantados en el Servicio de Nefrología Infantil del Hospital de Niños J. M. de los Ríos en Caracas - Venezuela. Se realizó un estudio descriptivo, de campo e intencional donde se seleccionaron 30 pacientes niños con edades entre los 7 y 17 años con insuficiencia renal crónica y/o transplantados de riñón y 30 niños no comprometidos sistémicamente. Todos los pacientes tenían un consentimiento informado de los padres y/o representantes como también los del grupo control. Se utilizó una Historia Clínica con datos socioepidemiológicos; se utilizó instrumental básico para el examen clínico intrabucal, revelador de placa dentoalveolar, vasillas indicadoras universal de Ph para la recolección de saliva y titulación de las mismas. El 77% de la población con insuficiencia renal crónica presentó hipoplasia del esmalte, el 93% presentó caries y la población control presentó el 50%, el 50% presentó gingivitis generalizada y el grupo control el 20%, el pH salival es más ácido en los niños con insuficiencia renal crónica y el grupo control mostró un pH neutro y alcalino y el 93% presentó xerostomía y el grupo control no presentó dicha afección; el 86% de los niños con insuficiencia renal crónica presentaron retardo de crecimiento, un 75% de retraso dentario y el 97% presentaron aumento del vello corporal. Los pacientes con insuficiencia renal crónica presentan alteraciones del aparato masticatorio que son propias de la enfermedad y también como consecuencia del tratamiento aplicado, por tal motivo el odontopediatra juega un papel importante en la instrucción a padres y/o representantes, médicos y paramédicos para el control y tratamiento de lesiones en boca de estos niños

The chronic renal shortage, is one of the nefropatias more known, which is a transtorn of etiology characterized by the decrease of Renal Function progress. The purpose of this work is to determine the oral dental patologic, in children with chronic renal shortage or transplanted at Servicio Infantil del Hospital de Niños J.M. de Los Rios in Caracas, Venezuela. A a descriptive study was made, in which were chosen 30 children patients from 7 to 17 years old with chronic renal shortage and/ or kidney transplanted, and 30 children not involved with this illness. All patients were authorized by their parents as well as the control Group. A clinical history was used with socioepidemiologic data, also the basic instruments to clinic intra- oral exam. The 77 % of population with chronic reanl shortage showed, the 93% showed dental cavity and the control population showed the 50%, the 50% showed and the control Group the 20%, the is more acid in childrens with chronic renal shortage and the control Group a neutral PH, and the 93% showed , and the control Group do not showed xerestomia; the 86 % of childrens with chronic renal shortage showed delay in raising, one 75 % of dental delay and the 97% showed an increase of corporal The patients with chronic renal shortage showed alterations in chewing apparatus, which are commons of this illness and also the consequence of treatment used, for this reason the dentist has an important rol in teaching to parents, medic and paramedic the control and treatment of this lesions in children.

Presentación inusual de un quiste dentígero en paciente pediátrico: reporte de un caso y revisión de la literatura / Unusual presentation of a dentigerous cyst in a pediatric patient: report of a case and review of the literature

El quiste dentígero es el quiste Odontogénico mas frecuente, generalmente se presenta rodeando la corona de un diente impactado, afecta a los caninos superiores y terceros molares inferiores, con mayor predilección en el sexo masculino, entre la segunda y tercera década de la vida . A continuación se presenta un caso clínico de un quiste dentígero mandibular inusual por presentar aspecto clínico y radiográfico de Osteomielitis crónica con osteítis proliferativa (Osteomielitis de Garré), en un paciente femenino de 7 años de edad con una evolución de 2 meses, Así mismo se describe la conducta clínica que se tomó con respecto al caso para llegar al diagnóstico definitivo.

The denture quiste it is the most frequent to surround the tooth, it affect the upper caninos and third below molars, the most affected is the male sex, between the second and third decade of life. It is showed a clinic case of a dental jaw quiste with an unusual apparience that suggest a Garre's Osteomyelitis cronic in a 7 year female patient, with an evolution of two months. Patient was subject to clinical, radiography and hystopatology test to confirm the final diagnostics of the lesion, and its described the clinical approachment in order to become the definitive diagnosis.

Presentación inusual de un hemangioma capilar lobulado en paciente pediátrico: reporte de un caso y revisión de la literatura / Unusual presentation of a lobular capillary hemangioma in a pediatric patient: report of a case and review of the literature

El hemangioma es un tumor benigno compuesto por vasos sanguíneos, el cual histopatologicamente presenta 2 variantes: hemangioma capilar, formado por canales capilares de pequeño diametro; hemangioma cavernoso, formado por grandes senos sanguíneos dilatados con paredes delgadas. Se presentan con mayor frecuencia en el sexo femenino y por lo general aparece pocos días después del nacimiento. La localización más frecuente en cavidad bucal es en la mucosa de los labios, lengua y carrillo. La lesión puede involucionar de forma espontanea o ser eliminada quirúrgicamente, en caso de que la lesión interfiera con alguna función del organismo. Su etiología es desconocida. Se reporta un caso de un paciente de sexo femenino de 6 años de edad que presenta lesión tumoral asintomática de color rosado con áreas ulcerativas y eritematosas de aspecto liso y brillante en el maxilar superior derecho ocasionando asimetría facial en dicha zona, dificultando la fonación y deglución. Se realizó biopsia insicional de la lesión con un diagnostico provisional de granuloma piogénico, se obtuvo como el resultado histopatológico hemangioma capilar lobular

The hemangioma is a benign tomour formed by sanguineos vases, wich present: 2 variants. Capillary Hemangioma: formed by capillary canals of small diameter; Cavernous Hemangioma: formed by great expanded sanguineous sines with thin walls. In most of the cases affect the femine sex and usually it appears after its birth. In bucal cavity the most frequently localization is in mucous of Lips, Tongue and Carrillo. The lesion can go back in spontaneous form or can be eliminated by surgery in the case that lesion affects any process of the organism. Its origin is unknown.Report of a 6 years feminine sex case, with an asymptomatic tumoral lesion and pink color, ulcerative and erythemative areas, its aspect is smooth and brilliant, located in superior right maxilar, causing facial asymmetry in this place. It was done an incisional biopsy of the lesion and the provisional diagnostic was: Granuloma Pyogenic, and the histopatologic result was: Hemangioma Capilar Lobular.

Prevalencia de la infección por virus papiloma humano en la cavidad bucal en pacientes pediátricos / Prevalence of human papillomavirus infection in the oral cavity in pediatric

El virus papiloma humano constituye un grupo viral heterogéneo capaz de producir lesiones hiperplasicas, papilomatosas y verrugosas tanto en piel como en mucosa, y en los últimos años se ha demostrado que juega un importante papel en la carcinogénesis. En nuestro país, la incidencia y Prevalencia de la infección es cada vez más alto, de allí la necesidad de resaltar la importancia de realizar un diagnostico precoz en niños de lesiones benignas en boca, lo cual permitiría un tratamiento preventivo adecuado de la lesión, evitando su transformación y progresión a las lesiones premalignas y/o malignas. El objetivo de esta investigación es determina la prevalencia del Virus Papiloma Humano en la cavidad bucal en un grupo de niños venezolanos, a los cuales se le realizó el examen clínico y biopsia de las lesiones encontradas con el fin de estudiarla histológicamente y determinar las manifestaciones más frecuentes en esta población, así como establecer la correlación clínica histopatológica que nos permite evaluar la cavidad la credibilidad del operador

Monitoring of bentonite pore water with a probe based on solid-state microsensors.

Repositories for the disposal of radioactive waste generally rely on a multi-barrier system to isolate the waste from the biosphere. This multi-barrier system typically comprises the natural geological barrier provided by the repository host rock and its surroundings and an engineered barrier system (EBS). Bentonite is being studied as an appropriated porous material for an EBS to prevent or delay the release and transport of radionuclides towards biosphere. The study of pore water chemistry within bentonite barriers will permit to understand the transport phenomena of radionuclides and obtain a database of the bentonite-water interaction processes. In this work, the measurement of some chemical parameters in bentonite pore water using solid-state microsensors is proposed. Those sensors are well suited for this application since in situ measurements are feasible and they are robust enough for the long periods of time that monitoring is needed in an EBS. A probe containing an ISFET (ion sensitive field effect transistor) for measuring pH, and platinum microelectrodes for measuring conductivity and redox potential was developed, together with the required instrumentation, to study the chemical changes in a test cell with compacted bentonite. Response features of the sensors' probe and instrumentation performance in synthetic samples with compositions similar to those present in bentonite barriers are reported. Measurements of sensors stability in a test cell are also presented.

Sub-cellular localisation of fukutin related protein in different cell lines and in the muscle of patients with MDC1C and LGMD2I.

MDC1C and LGMD2I are two allelic forms of muscular dystrophies caused by mutations in the gene encoding for fukutin related protein (FKRP). FKRP encodes for a putative glycosyltransferase, the precise function of which is unknown. However, the marked reduction of alpha-dystroglycan glycosylation in the muscle of MDC1C and LGMD2I patients suggests a role for FKRP in dystroglycan processing. Using a polyclonal antibody raised against FKRP we now show that endogenous FKRP locates to the Golgi apparatus of neuronal, oligodendroglial, and the cardiac muscle cell line H9c2. In differentiated C2C12 myotubes and in transverse sections of normal skeletal and cardiac muscle, endogenous FKRP surrounded the myonuclei. This localisation was unaffected in the skeletal muscle of patients with MDC1C and LGMD2I carrying various FKRP mutations. These observations imply a specific role for FKRP during striated muscle, neuronal and glial development and suggest that protein mis-localisation is not a common mechanism of disease in FKRP-related dystrophies.