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1.
Appl Opt ; 62(24): 6534-6541, 2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37706848

RESUMEN

In this work, we study multimodal interference filters with a graphite oxide coating. Use of the multimodal interference filter shows a distinctive peak in the signal spectrum, and when using the exfoliated graphite coated multimodal interference filter, the signal shows different spectral changes, such as the full width at half maximum of the curve, the maximum power, and central wavelength, which indicates that graphite oxide absorbs part of the energy. In addition, microscope observations when a He-Ne laser is passed through the filter confirm that graphite oxide is adhered to the filter.

2.
Ginecol Obstet Mex ; 84(3): 164-71, 2016 Mar.
Artículo en Español | MEDLINE | ID: mdl-27424442

RESUMEN

BACKGROUND: Fetal macrosomia is birth weight of 4,000 grams or more, regardless of gestational age, in Mexico representing about 5.4%. Associated with multiple demographic, physiological, metabolic and genetic factors of each population. OBJECTIVE: Determine the risk factors associated with the development of fetal macrosomia in patients without gestational diabetes mellitus. METHODS: Retrospective, descriptive and comparative study of patients who came to delivery from January 2012 to June 2014, 88 patients, 23 patients with diagnosis of macrosomia, and 65 patients without macrosomia without gestational diabetes mellitus were included. RESULTS: An incidence of fetal macrosomia of 18.6%. Risk factors such as parity, history of fetal macrosomia, maternal age, maternal height more to 1.70 meters showed no difference, the percentage of overweight 105% showed 69% vs 52% on the control group and gestational diabetes screening altered that present 30.4 vs 20%. CONCLUSIONS: Increased incidence of macrosomia was demonstrated in patients with metabolic factors such as the percentage of overweight and screening altered gestational diabetes mellitus, as they showed higher prevalence in the study group, all modifiable with preconception nutritional management and during pregnancy, to reduce initial weight and weight gain, improved fasting and postprandial blood glucose in patients with positive screening and negative tolerance curve carbohydrates to maintain fetal growth curve with in the percentiles.


Asunto(s)
Macrosomía Fetal/epidemiología , Adolescente , Adulto , Diabetes Gestacional , Femenino , Humanos , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
4.
Eur Phys J E Soft Matter ; 37(11): 119, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25416243

RESUMEN

We study via numerical simulations a granular chain not only with decreasing radii (forward tapering) in geometric progression, but also decorated with grains positioned on the top and bottom of the chain, without altering its original length. The decorating grains act as an auxiliary chain which traps part of the energy and linear momentum, both propagating as a pulse due to disturbances produced at the end of the chain. Thus, this configuration optimizes the impact attenuation and aligns the chain naturally (by symmetry) which facilitates the construction of the experimental setup. Furtheremore, since the decorating grain radii increase along the chain, this new type of chain is necessarily short in order to avoid precompression. Nevertheless, even with short chains, it is possible to mitigate impacts almost completely.

5.
Acta Trop ; 257: 107329, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39033969

RESUMEN

In Triatoma infestans it was observed pyrethroid resistance attributed in part to an elevated oxidative metabolism mediated by cytochromes P450. The nicotinamide adenine dinucleotide phosphate (NADPH) cytochrome P450 reductase (CPR) plays a crucial role in catalysing the electron transfer from NADPH to all cytochrome P450s. The daily variations in the expression of CPR gene and a P450 gene (CYP4EM7), both associated with insecticide resistance, suggested that their expressions would be under the endogenous clock control. To clarify the involvement of the clock in orchestration of the daily fluctuations in CPR and CYP4M7 genes expression, it was proposed to investigate the effect of silencing the clock gene period (per) by RNA interference (RNAi). The results obtained allowed to establish that the silencing of per gene was influenced by intake schemes used in the interference protocols. The silencing of per gene in T. infestans reduced its expression at all the time points analysed and abolished the characteristic rhythm in the transcriptional expression of per mRNA. The effect of the per gene silencing in the expression profiles at the transcriptional level of CPR and CYP4EM7 genes showed the loss of rhythmicity and demonstrated the biological clock involvement in the regulation of t heir expression.


Asunto(s)
Ritmo Circadiano , Resistencia a los Insecticidas , Interferencia de ARN , Triatoma , Animales , Triatoma/genética , Triatoma/efectos de los fármacos , Resistencia a los Insecticidas/genética , Ritmo Circadiano/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/genética , NADPH-Ferrihemoproteína Reductasa/genética , NADPH-Ferrihemoproteína Reductasa/metabolismo , Vectores de Enfermedades
6.
Clin Transl Radiat Oncol ; 45: 100753, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38433951

RESUMEN

Background: Pancreatic Stereotactic Body Radiotherapy (SBRT) allows for the administration of a higher biologically effective doses (BED), that would be essential to achieve durable tumor control. Escalating treatment doses need a very accurate tumor positioning and motion control during radiotherapy.The aim of this study to assess the feasibility and safety of a Simultaneous Integrated Boost (SIB) dose-escalated protocol at 45 Gy, 50 Gy and 55 Gy in 5 consecutive daily fractions, in Border Line Resectable Pancreatic Cancer (BRCP) /Locally Advanced Pancreatic Cancer (LAPC) by means of a standard LINAC platform. Methods: Patients diagnosed of BRPC/LAPC, candidates for neoadjuvant chemotherapy and SBRT, in four university hospitals of the province of Las Palmas (Canary Islands, Spain) were included in this prospective study. Radiotherapy was administered using standard technology (LINACS) with advanced positioning (Lipiodol® and metallic stent used as fiducial markers) and tumor motion control (4D, DBH, Calypso®). There were 3 planned dose-escalated SIB groups, 45 Gy/5f (9 patients) 50 Gy/5f (9 + 9 patients) and 55 Gy/5f (9 patients). The defined primary end points of the study were the safety and feasibility of the proposed treatment protocol. Secondary endpoints included radiological tumor response after SBRT, local control and survival. Results: From June 2017 to December 2022, sixty-two patients were initially assessed for eligibility in the study in the four participating centers, and 49 were candidates for chemotherapy (CHT). Forty-one were referred to radiotherapy after CHT and 33 finally were treated by escalated-dose SIB, 45 Gy (9 patients) 50 Gy (16 patients), 55 Gy(8 patients). All patients completed the scheduled treatment and no acute or late severe (≥grade3) gastrointestinal toxicity was observed.Local response was analyzed by CT/MRI two months after the end of SBRT. Ten patients (31,25 %) achieved objective response (2/9:45 Gy, 5/15:50 Gy, 3/8:55 Gy). Follow-up was closed as July 2023. Freedom from local progression at 1-2y were 89,3% (95 %CI:83,4-95,2%) and 66 % (95 %CI:54,6-77,4%) respectively. The 1-2y survival rates were 95,7% (95 %CI:91,4-100 % and 48,6% (95 %CI:37,7-59,5%) respectively. Conclusion: These promising results should be confirmed by further studies with larger sample size and extended follow-up period.

7.
J Hum Evol ; 64(6): 678-86, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23615378

RESUMEN

Two Neandertal specimens from El Sidrón, northern Spain, show evidence of retained left mandibular deciduous canines. These individuals share the same mitochondrial (mtDNA) haplotype, indicating they are maternally related and suggesting a potential heritable basis for these dental anomalies. Radiographs and medical CT scans provide evidence of further, more extensive dental pathology in one of these specimens. An anomalous deciduous canine crown morphology that developed before birth subsequently suffered a fracture of the crown exposing the pulp sometime after eruption into functional occlusion. This led to death of the tooth, periapical granuloma formation and arrested deciduous canine root growth at an estimated age of 2.5 years. At some point the underlying permanent canine tooth became horizontally displaced and came to lie low in the trabecular bone of the mandibular corpus. A dentigerous cyst then developed around the crown. Anterior growth displacement of the mandible continued around the stationary permanent canine, leaving it posteriorly positioned in the mandibular corpus by the end of the growth period beneath the third permanent molar roots, which, in turn, suggests a largely horizontal growth vector. Subsequent longstanding repeated infections of the expanding cyst cavity are evidenced by bouts of bone deposition and resorption of the boundary walls of the cyst cavity. This resulted in the establishment of two permanent bony drainage sinuses, one through the buccal plate of the alveolar bone anteriorly, immediately beneath the infected deciduous canine root, and the other through the buccal plate anterior to the mesial root of the first permanent molar. It is probable that this complicated temporal sequence of dental pathologies had an initial heritable trigger that progressed in an unusually complex way in one of these individuals. During life, this individual may have been largely unaware of this ongoing pathology.


Asunto(s)
Diente Canino/patología , ADN Mitocondrial/genética , Mandíbula/patología , Hombre de Neandertal/anatomía & histología , Adolescente , Animales , Diente Canino/diagnóstico por imagen , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Hombre de Neandertal/genética , España , Tomografía Computarizada por Rayos X , Adulto Joven
8.
Materials (Basel) ; 16(4)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36837137

RESUMEN

This material can be considered to be an interesting eco-friendly choice to be used in the photovoltaic field. In this work, we present the fabrication of Cu3N thin films by reactive radio-frequency (RF) magnetron sputtering at room temperature, using nitrogen as the process gas. Different RF power values ranged from 25 to 200 W and gas pressures of 3.5 and 5 Pa were tested to determine their impact on the film properties. The morphology and structure were exhaustively examined by Atomic Force Microscopy (AFM), Fourier Transform Infrared (FTIR) and Raman Spectroscopies and X-ray Diffraction (XRD), respectively. The AFM micrographs revealed different morphologies depending on the total pressure used, and rougher surfaces when the films were deposited at the lowest pressure; whereas FTIR and Raman spectra exhibited the characteristics bands related to the Cu-N bonds of Cu3N. Such bands became narrower as the RF power increased. XRD patterns showed the (100) plane as the preferred orientation, that changed to (111) with the RF power, revealing a worsening in structural quality. Finally, the band gap energy was estimated from transmission spectra carried out with a Perkin Elmer 1050 spectrophotometer to evaluate the suitability of Cu3N as a light absorber. The values obtained demonstrated the capability of Cu3N for solar energy conversion applications, indicating a better film performance under the sputtering conditions 5.0 Pa and RF power values ranged from 50 to 100 W.

9.
Clin Transl Radiat Oncol ; 40: 100620, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37066113

RESUMEN

Background/purpose: The aim of this study is to assess for the first time the immediate and long term impact on quality-of-life of HBO treatments(HBOT) at 1.45 ATA (Absolute Atmospheric Pressure) Medical Hyperbaric chamber. Methods: Patients over 18 years-old, suffering of grade 3 Common Terminology Criteria for Adverse Events (CTCAE) 4.0 radiation induced late toxicity and progressing to standard support therapy were included in this prospective study. HBOT was given daily, sixty minutes per session by a Medical Hyperbaric Chamber Biobarica System at 1.45 ATA at 100% O2. Forty sessions were prescribed for all patients given in 8 weeks. Patients reported outcomes (PROs) was assessed by the QLQ-C30 questionnaire, before starting, in the last week of the treatment, as well as during follow up. Results: Between February-2018/June-2021, 48 patients fulfilled the inclusion criteria. A total of 37 patients (77%) completed the treatment prescribed HBOT sessions. Patients with anal fibrosis (9/37) and brain necrosis (7/37) were the most frequently treated. The most common symptoms were pain (65%) and bleeding (54%). In addition, thirty out of the 37 patients who completed the pre- and post-treatment Patients Reported Outcomes (PROs) assessment also completed the follow up European Organization for Research and Treatment of Cancer, Quality of Life Questionnaire C30 (EORTC-QLQ-C30), and were evaluated in the present study. Mean follow up was 22,10 (6-39) months.The Median score of the EORTC-QLQ-C30, at the end of HBOT and during follow-up, was improved in all assessed domains, except in the cognitive aspect (p = 0.106). Conclusions: HBOT at 1.45 ATA is a feasible and well tolerated treatment, improving long term quality of life in terms of physical function, daily activities and general health subjective state of patients suffering severe late radiation-induced toxicity.

10.
Rev Gastroenterol Mex (Engl Ed) ; 87(1): 44-51, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34635447

RESUMEN

INTRODUCTION AND AIMS: Oropharyngeal dysphagia (OD) occurs in children with cerebral palsy. It is important to investigate its relationship with some variables, and the objective of this study was to identify factors associated with OD. MATERIALS AND METHODS: Case-control study in patients with cerebral palsy from 8months to 15years of age, from November 2018 to November 2019, approved by the Ethics Committee. The diagnosis of OD was made by videofluoroscopy when there was nasopharyngeal reflux, stagnation in the vallecular sinuses, in the piriformis sinuses, penetration, and aspiration. The independent variables were type of cerebral palsy, gross motor impairment classified into five levels, nutritional status and comorbidities. One case with OD was included and the next one without alterations in videofluoroscopy was control. The variables were compared with Chi square and Student's t. The association was measured with odds ratio. The confidence interval was 95%. RESULTS: Thirty patients with OD and 30without OD were studied. Sex, age, birth weight, and gestational age had a similar distribution in the two groups. From the data perceived by the mothers at the time of feeding, the greater frequency of the difficulty in the transfer of the food bolus in the group with OD showed a statistically significant difference (P<.001) and of the studied factors, the levelV of the gross motor involvement was associated with a higher frequency of OD. CONCLUSIONS: OD was associated with level V of gross motor involvement.


Asunto(s)
Parálisis Cerebral , Trastornos de Deglución , Estudios de Casos y Controles , Niño , Estudios Transversales , Trastornos de Deglución/etiología , Humanos , Estado Nutricional
11.
J Neurosci Res ; 89(3): 352-64, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21259322

RESUMEN

Sphingolipids are intrinsic components of membrane lipid rafts. The abnormal accumulation of these molecules may introduce architectural and functional changes in these domains, leading to cellular dysfunction. Galactosylsphingosine (psychosine) is a pathogenic lipid raft-associated molecule whose accumulation leads to brain deterioration and irreversible neurological handicap in the incurable leukodystrophy Krabbe disease (KD). The relevance of clearing excessive levels of pathogenic psychosine from lipid rafts in therapy for KD has not been investigated. The work presented here demonstrates that psychosine inhibits raft-mediated endocytosis in neural cells. In addition, although in vitro enzyme reconstitution is sufficient for the reversal of related endocytic defects in affected neural cells, traditional in vivo enzyme therapies in the mouse model of KD appear to be insufficient for complete removal of pathogenic levels of raft-associated psychosine. This work describes a mechanism that may contribute to limiting the in vivo efficacy of traditional therapies for KD.


Asunto(s)
Leucodistrofia de Células Globoides/patología , Leucodistrofia de Células Globoides/terapia , Microdominios de Membrana/efectos de los fármacos , Neuronas/patología , Psicosina/farmacología , Animales , Animales Recién Nacidos , Trasplante de Médula Ósea/métodos , Encéfalo/patología , Células Cultivadas , Toxina del Cólera/metabolismo , Clatrina , Modelos Animales de Enfermedad , Endocitosis/genética , Endocitosis/fisiología , Terapia de Reemplazo Enzimático/métodos , Galactosilceramidasa/genética , Galactosilceramidasa/metabolismo , Humanos , Espectrometría de Masas , Ratones , Proteína Quinasa C/metabolismo , Psicosina/metabolismo , Factores de Tiempo
12.
Heredity (Edinb) ; 107(1): 71-9, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21224874

RESUMEN

Triatoma infestans is the main vector of Chagas' disease in South America between latitudes 10°S and 46°S. A multilocus microsatellite data set of 836 individuals from 27 populations of T. infestans, from all its range of distribution in Argentina, was analyzed. Our results favor the hypothesis of two independent migration events of colonization in Argentina and secondary contacts. The majority of the populations of the western provinces of Catamarca, La Rioja, San Juan and the west of Cordoba province, had almost no shared ancestry with the rest of the populations analyzed. Probably those populations, belonging to localities close to the Andean region, could have been established by the dispersal line of T. infestans that would have arrived to Argentina through the Andes, whereas most of the rest of the populations analyzed may have derived from the dispersal line of T. infestans in non-Andean lowlands. Among them, those from the provinces of Formosa, Chaco, Santiago del Estero and Santa Fe shared different percentages of ancestry and presented lower degree of genetic differentiation. The migratory movement linked to regional economies and possibly associated with passive dispersal, would allow a higher genetic exchange among these populations of T. infestans. This study, using microsatellite markers, provides a new approach for evaluating the validity of the different hypotheses concerning the evolutionary history of this species. Two major lineages of T. infestans, an Andean and non-Andean, are suggested.


Asunto(s)
Enfermedad de Chagas/transmisión , Insectos Vectores/genética , Triatoma/genética , Animales , Argentina , Geografía , Control de Insectos/métodos , Repeticiones de Microsatélite , Filogenia , Triatoma/patogenicidad
13.
Appl Opt ; 50(3): 253-60, 2011 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-21263718

RESUMEN

We present detailed investigations of the spectral dependencies of the transmission of a fiber optical loop mirror (FOLM) consisting of a coupler with output ports spliced at arbitrary angles to a high-birefringence (Hi-Bi) fiber. The application for dual-wavelength lasers is discussed. For this aim, the spectral dependence of the reflection is tuned by the temperature of the Hi-Bi fiber that allows a fine adjustment of the cavity loss for generated wavelengths. The ratio between maximum and minimum reflection can be adjusted by the twist angle of the fiber at the splices, which also provides useful possibilities for the adjustment of cavity losses. We used the twist and temperature variation of the Hi-Bi fiber to change the operation from single wavelength to stable dual-wavelength generation with either equal or unequal powers of wavelengths.

14.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33573860

RESUMEN

INTRODUCTION AND AIMS: Oropharyngeal dysphagia (OD) occurs in children with cerebral palsy. It is important to investigate its relationship with some variables, and the objective of this study was to identify factors associated with OD. MATERIALS AND METHODS: Case-control study in patients with cerebral palsy from 8months to 15years of age, from November 2018 to November 2019, approved by the Ethics Committee. The diagnosis of OD was made by videofluoroscopy when there was nasopharyngeal reflux, stagnation in the vallecular sinuses, in the piriformis sinuses, penetration, and aspiration. The independent variables were type of cerebral palsy, gross motor impairment classified into five levels, nutritional status and comorbidities. One case with OD was included and the next one without alterations in videofluoroscopy was control. The variables were compared with Chi square and Student's t. The association was measured with odds ratio. The confidence interval was 95%. RESULTS: Thirty patients with OD and 30without OD were studied. Sex, age, birth weight, and gestational age had a similar distribution in the two groups. From the data perceived by the mothers at the time of feeding, the greater frequency of the difficulty in the transfer of the food bolus in the group with OD showed a statistically significant difference (P<.001) and of the studied factors, the levelV of the gross motor involvement was associated with a higher frequency of OD. CONCLUSIONS: OD was associated with level V of gross motor involvement.

15.
Opt Express ; 18(3): 2090-9, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20174037

RESUMEN

We demonstrate the extraction of a single soliton from a bunch of solitons generated by the pulse breakup effect. The bunch of solitons was generated in a 500-m fiber pumped by 25-ps pulses. For the extraction of single soliton from the bunch we use a nonlinear optical loop mirror (NOLM). At its output we detected a pulse with full width at half-maximum (FWHM) of 0.99 ps whose autocorrelation trace corresponds to that of a soliton. Our results demonstrate that the suggested method can be useful for soliton generation, and also for investigations of the initial stage of the soliton formation process.

16.
J Chromatogr A ; 1611: 460577, 2020 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-31591040

RESUMEN

Ultraviolet radiation from sunlight causes DNA damage in skin cells by formation of photoproducts, mainly cyclobutane pyrimidine dimers (CPD), which are reverted by exogenous CPD-photolyase, preventing photoaging and skin cancer. High performance liquid chromatography tandem mass spectrometry method for quantification of CPD-photolyase activity was developed to search new enzymes sources for dermatology or clinical studies. The method was based in the enzymatic conversion of a 15mer oligonucleotide, containing a center cyclobutane thymidine dimer, to the restored 15mer oligonucleotide. Three ion pair reagent were evaluated by response surface methodology to increase mass intensities. Additionally, chromatographic separation of oligonucleotides was performed. The selected mobile phase was 15 mM diisopropylethylamine/20 mM hexafluoroisopropanol in methanol. The method allowed total separation between the oligonucleotides studied (resolution of 2.3) by using the core shell technology, which reduce the diffusion time of the analyte into the column, increasing the efficiency and minimizing the analysis time at 7 min. The mass spectrometry detection allowed a high selectivity and sensitivity. This is the first time where MRM modality has been employed with this specific purpose. Oligonucleotides recovery from reaction mixture was ∼ 94% and the limit of quantification was 13.4 nM for 15mer. The method was evaluated with a recombinant CPD-photolyase from Synechococcus leopoliensis using purified and crude protein extract. CPD-photolyase could be measured in terms of activity for enzymatic kinetics studies, for evaluation of UV-R effects in (micro)organisms and to identify new enzymes.


Asunto(s)
Proteínas Bacterianas/química , Cromatografía Liquida/métodos , Desoxirribodipirimidina Fotoliasa/química , Pruebas de Enzimas/métodos , Oligonucleótidos/análisis , Synechococcus/enzimología , Espectrometría de Masas en Tándem/métodos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biocatálisis , Desoxirribodipirimidina Fotoliasa/genética , Desoxirribodipirimidina Fotoliasa/metabolismo , Cinética , Dímeros de Pirimidina/química , Synechococcus/química , Synechococcus/genética
17.
J Air Waste Manag Assoc ; 70(10): 1043-1059, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32845797

RESUMEN

A case study was conducted to evaluate the SO2 emission reduction in a power plant in Central Mexico, as a result of the shifting of fuel oil to natural gas. Emissions of criteria pollutants, greenhouse gases, organic and inorganic toxics were estimated based on a 2010 report of hourly fuel oil consumption at the "Francisco Pérez Ríos" power plant in Tula, Mexico. For SO2, the dispersion of these emissions was assessed with the CALPUFF dispersion model. Emissions reductions of > 99% for SO2, PM and Pb, as well as reductions >50% for organic and inorganic toxics were observed when simulating the use of natural gas. Maximum annual (993 µg/m3) and monthly average SO2 concentrations were simulated during the cold-dry period (152-1063 µg/m3), and warm-dry period (239-432 µg/m3). Dispersion model results and those from Mexico City's air quality forecasting system showed that SO2 emissions from the power plant affect the north of Mexico City in the cold-dry period. The evaluation of model estimates with 24 hr SO2 measured concentrations at Tepeji del Rio suggests that the combination of observations and dispersion models are useful in assessing the reduction of SO2 emissions due to shifting in fuels. Being SO2 a major precursor of acid rain, high transported sulfate concentrations are of concern and low pH values have been reported in the south of Mexico City, indicating that secondary SO2 products emitted in the power plant can be transported to Mexico City under specific atmospheric conditions. Implications: Although the surroundings of a power plant located north of Mexico City receives most of the direct SO2 impact from fuel oil emissions, the plume is dispersed and advected to the Mexico City metropolitan area, where its secondary products may cause acid rain. The use of cleaner fuels may assure significant SO2 reductions in the plant emissions and consequent acid rain presence in nearby populated cities and should be compulsory in critical areas to comply with annual emission limits and health standards.


Asunto(s)
Contaminantes Atmosféricos/análisis , Aceites Combustibles , Gas Natural , Centrales Eléctricas , Contaminación del Aire/análisis , Monitoreo del Ambiente , Plomo/análisis , México , Material Particulado/análisis , Dióxido de Azufre/análisis
18.
J Neurosci Res ; 87(8): 1748-59, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19185028

RESUMEN

This study characterized the therapeutic benefits of combining hematogenous cell replacement with lentiviral-mediated gene transfer of galactosylceramidase (GALC) in Twitcher mice, a bona fide model for Krabbe disease. Bone marrow cells and GALC-lentiviral vectors were administered intravenously without any preconditioning to newborn Twitcher pups before postnatal day 2. Treated Twitchers survived up to 4 months of age. GALC activity remained less than 5% of normal values in the nervous system for the first 2 months after treatment and reached approximately 30% in long-term-surviving mice. Long-term reconstitution of GALC activity in the nervous system was provided primarily by infiltrating macrophages and to a lesser extent by direct lentiviral transduction of neural cells. Treated Twitchers had significant preservation of myelin, with a G-ratio (ratio of the axon diameter to the diameter of the myelinated fiber) in sciatic nerve myelin of 0.75 +/- 0.08 compared with 0.85 +/- 0.10 in untreated mutants. Although treated mutants had improved locomotor activities during their long-term survival, they died with symptoms of progressive neurological degeneration, indistinguishable from those seen in untreated Twitchers. Examination of long-lived Twitchers showed that treated mutants were not protected from developing degeneration of axons throughout the neuroaxis. These results suggest that GALC deficiency not only affects myelinating glia but also leads to neuronal dysfunction. The contemporaneous neuropathology might help to explain the limited efficacy of current gene and cell therapies.


Asunto(s)
Terapia Genética/métodos , Trasplante de Células Madre Hematopoyéticas/métodos , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/terapia , Trastornos Heredodegenerativos del Sistema Nervioso/terapia , Lentivirus/genética , Leucodistrofia de Células Globoides/terapia , Animales , Animales Recién Nacidos , Trasplante de Médula Ósea/métodos , Modelos Animales de Enfermedad , Galactosilceramidasa/genética , Técnicas de Transferencia de Gen , Vectores Genéticos/genética , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/genética , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/fisiopatología , Trastornos Heredodegenerativos del Sistema Nervioso/genética , Trastornos Heredodegenerativos del Sistema Nervioso/fisiopatología , Leucodistrofia de Células Globoides/genética , Leucodistrofia de Células Globoides/fisiopatología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes Neurológicos , Regeneración Nerviosa/genética , Tasa de Supervivencia , Resultado del Tratamiento
19.
Science ; 276(5317): 1392-5, 1997 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-9162001

RESUMEN

Human fossil remains recovered from the TD6 level (Aurora stratum) of the lower Pleistocene cave site of Gran Dolina, Sierra de Atapuerca, Spain, exhibit a unique combination of cranial, mandibular, and dental traits and are suggested as a new species of Homo-H. antecessor sp. nov. The fully modern midfacial morphology of the fossils antedates other evidence of this feature by about 650, 000 years. The midfacial and subnasal morphology of modern humans may be a retention of a juvenile pattern that was not yet present in H. ergaster. Homo antecessor may represent the last common ancestor for Neandertals and modern humans.


Asunto(s)
Fósiles , Hominidae , Adulto , Animales , Niño , Dentición , Huesos Faciales , Hominidae/clasificación , Humanos , Mandíbula , Cráneo , España
20.
Science ; 269(5225): 826-30, 1995 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-7638598

RESUMEN

Human remains dating to more than 780,000 years ago are associated with a rich faunal and lithic assemblage in the Pleistocene cave site of Gran Dolina (TD), Sierra de Atapuerca, Burgos, Spain. The micromammal species represent the late Biharian (Mimomys savini zone), and the lithic objects represent pre-Acheulean technology (Mode 1) and comes from the TD6 level below the Matuyama-Brunhes boundary. The Gran Dolina hominid fossils cannot be comfortably accommodated in any of the defined Homo species. They could be considered a primitive form of Homo heidelbergensis, but a new species might be named in the future if the sample is enlarged. The new human fossil evidence demonstrates that Western Europe was settled at least since the late early Pleistocene.


Asunto(s)
Fósiles , Hominidae , Animales , Historia del Siglo XX , Historia Antigua , Hominidae/anatomía & histología , Hominidae/clasificación , Humanos , Paleodontología , España , Diente/anatomía & histología
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