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2.
Nature ; 571(7765): E7, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31263274

RESUMEN

Change history: In this Article, the original affiliation 2 was not applicable and has been removed. In addition, in the Acknowledgements there was a statement missing and an error in a name. These errors have been corrected online.

3.
Nature ; 568(7753): 487-492, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-31019327

RESUMEN

Carbon and other volatiles in the form of gases, fluids or mineral phases are transported from Earth's surface into the mantle at convergent margins, where the oceanic crust subducts beneath the continental crust. The efficiency of this transfer has profound implications for the nature and scale of geochemical heterogeneities in Earth's deep mantle and shallow crustal reservoirs, as well as Earth's oxidation state. However, the proportions of volatiles released from the forearc and backarc are not well constrained compared to fluxes from the volcanic arc front. Here we use helium and carbon isotope data from deeply sourced springs along two cross-arc transects to show that about 91 per cent of carbon released from the slab and mantle beneath the Costa Rican forearc is sequestered within the crust by calcite deposition. Around an additional three per cent is incorporated into the biomass through microbial chemolithoautotrophy, whereby microbes assimilate inorganic carbon into biomass. We estimate that between 1.2 × 108 and 1.3 × 1010 moles of carbon dioxide per year are released from the slab beneath the forearc, and thus up to about 19 per cent less carbon is being transferred into Earth's deep mantle than previously estimated.


Asunto(s)
Dióxido de Carbono/análisis , Secuestro de Carbono , Sedimentos Geológicos/química , Biomasa , Isótopos de Carbono , Costa Rica , Sedimentos Geológicos/microbiología , Helio
4.
J Postgrad Med ; 64(3): 186-189, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29943739

RESUMEN

Ureterocolic fistulae are a rare phenomenon and are most commonly seen secondary to obstructive ureteric calculi. These are usually diagnosed on barium enema or intravenous urography. Most of the times, more than one investigation is needed to confirm the findings. We present a case of iatrogenically-induced ureterocolic fistula, diagnosed on renogram and direct radionuclide cystography. This case showcases the possibility of using a renogram study as a diagnostic tool for a suspected ureterocolic fistula. A renogram study also enables to asess the renal function, which is essential in deciding the management.


Asunto(s)
Cistografía/métodos , Renografía por Radioisótopo/métodos , Cólico Renal/diagnóstico por imagen , Enfermedades Ureterales/diagnóstico por imagen , Fístula Urinaria/diagnóstico por imagen , Adulto , Diuréticos , Femenino , Humanos
5.
Int J Cosmet Sci ; 37(5): 542-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25899568

RESUMEN

OBJECTIVE: The skin melanin system is affected by ageing, resulting in dyspigmentation with associated clinical and psychosocial consequences. In dark skinned phenotypes, broad evidence is available, whereas little is known about pigmentary changes in fair-skinned Caucasians. The objective of this study was to investigate age-related changes in facial pigmentation and dyspigmentation in subjects of skin phototypes II-III and to develop and test parameters for quantifying dyspigmentation. METHODS: Twenty-four skin healthy female subjects were recruited in three distinct age groups (30-40, 50-60, 70-80 years). Skin colour was measured by Mexameter and Chromameter. Skin dyspigmentation was measured by clinical evaluation and newly developed image-processing parameters on the cheeks and the forehead. The reliability of the clinical evaluation was investigated by intraclass correlation coefficients between three raters, and the validity of the dyspigmentation parameters was analysed by bivariate correlations with related measures. RESULTS: Skin lightness decreased with increasing age. Clinical dyspigmentation scores showed positive associations with chronological age ranging between 0.452 and 0.606. RBX(®) -Brown transformation-based hyperpigmentation and hypopigmentation indices increased with age, whereas the overall pigmentation intensity decreased with age at the cheeks. The image analysis-based parameters showed strong associations with the clinical scores and related measurements. CONCLUSION: We demonstrated age-related changes in the facial colour and dyspigmentation of fair-skinned Caucasian females. An increase in dyspigmentation was found by clinical scoring and the RBX(®) -Brown transformation-based pigmentation indices. The validity of hyper- and hypopigmentation indices and overall pigmentation intensity was supported. The RBX(®) transformation-based pigmentation indices might be applied in future studies to complement or substitute clinical evaluation.


Asunto(s)
Envejecimiento de la Piel , Pigmentación de la Piel , Adulto , Humanos
7.
J Neurooncol ; 107(1): 165-74, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21964738

RESUMEN

Limited research is available regarding the efficacy of psychostimulants in treating cognitive function in primary brain tumor patients. An open-label, randomized, pilot trial examined both the general and differential efficacy of 4 weeks of methylphenidate (MPH) and modafinil (MOD) in 24 brain tumor patients. Participants completed cognitive tests and self-report measures of fatigue, sleep disturbance, mood and quality of life at baseline and after 4 weeks.Following stimulant treatment, there was evidence of a beneficial effect on test performance in speed of processing and executive function requiring divided attention. Patients with the greatest deficit in executive function at baseline appeared to derive the greatest benefit following stimulant therapy. Inconsistent, differential effects were found on a measure of attention in favor of MPH and on a measure of processing speed in favor of MOD. There was also evidence of a general beneficial effect on patient-reported measures of fatigue, mood, and quality of life, with no statistically significant differences between treatment arms in these measures over time. The results from this small pilot study should be interpreted with caution, but appear to warrant additional research, in larger study samples, targeting fatigue, processing speed and executive function, and exploring different doses of stimulants. Future studies may also wish to explore the specific patient factors that may be associated with responsiveness to psychostimulant treatment.


Asunto(s)
Compuestos de Bencidrilo/uso terapéutico , Neoplasias Encefálicas/complicaciones , Estimulantes del Sistema Nervioso Central/uso terapéutico , Trastornos del Conocimiento/tratamiento farmacológico , Glioma/complicaciones , Metilfenidato/uso terapéutico , Adulto , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/etiología , Femenino , Estudios de Seguimiento , Glioma/patología , Glioma/terapia , Humanos , Masculino , Persona de Mediana Edad , Modafinilo , Clasificación del Tumor , Proyectos Piloto , Pronóstico
8.
Dalton Trans ; 49(4): 1334, 2020 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-31932819

RESUMEN

Correction for 'Azamacrocycles and tertiary amines can be used to form size tuneable hollow structures or monodisperse oxide nanoparticles depending on the 'M' source' by Graham E. Tilburey, et al., Dalton Trans., 2019, 48, 15470-15479.

9.
Dalton Trans ; 48(41): 15470-15479, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31259981

RESUMEN

We show that the azamacrocycle 'cyclam' (1,4,8,11-tetraazacyclodecane) in conjunction with a silicon catecholate ion generates novel hollow tetragonal tube-like crystalline materials [(C6H4O2)3Si][C10H26N4]·H2O, whose dimensions can be tuned according to the pH of the reaction medium. The synthesis approach was successful for both silicon and germanium and we hypothesise that a range of other catecholate precursors of elements such as iron could be used to generate a large array of inorganic materials with interesting morphologies. The synthesis approach can be extended to tertiary diamines with functional group spacing playing an important role in the efficacy of complexation. Of the molecules explored to date, a C2 spacing (N,N,N',N'-tetramethylethylenediamine (4MEDAE)), leads to the most efficient structure control with hollow hexagonal tube-like structures being formed. In addition, we show that azamacrocycles, in the presence of unbuffered tetramethoxysilane (TMOS) solutions can be used to manipulate silica formation and provide a fast (ca. 10 minutes) synthesis route to particles whose diameter can be tuned from ca. 20 nm to several hundreds of nm under reaction conditions (no extremes of pH) that make the sols suitable for direct use in biotechnological applications.

10.
BJOG ; 115(7): 818-22, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18485158

RESUMEN

OBJECTIVE: To assess the effects of aromatase inhibitors in women symptomatic of pain with endometriosis. DESIGN: A systematic review of published literature. MATERIAL AND METHODS: We conducted a comprehensive literature search to identify all the published observational and randomised studies evaluating the efficacy of aromatase inhibitors on pain associated with endometriosis. A combination of keywords was used to identify the maximum number of relevant citations in MEDLINE, EMBASE, CINAHL and the Cochrane Database. Outcome Pain relief, lesion size and quality of life. RESULTS: There were eight studies (137 women) evaluating outcomes of aromatase inhibitors. In case series/reports (seven studies, 40 women), aromatase inhibitors combined with progestogens or oral contraceptive pill or gonadotrophin-releasing hormone (GnRH) analogues reduced mean pain scores and lesion size and improved quality of life. An RCT (97 women) demonstrated that aromatase inhibitors in combination with GnRH analogues significantly improved pain (P < 0.0001) compared with GnRH analogues alone together with significant improvement in multidimensional patient scores (P < 0.0001). There was no significant reduction in spine or hip-bone densities. CONCLUSION: Aromatase inhibitors appear to have a promising effect on pain associated with endometriosis, but the strength of this inference is limited due to a dearth of the evidence available.


Asunto(s)
Inhibidores de la Aromatasa/uso terapéutico , Endometriosis/complicaciones , Dolor Pélvico/tratamiento farmacológico , Analgésicos/uso terapéutico , Inhibidores de la Angiogénesis/uso terapéutico , Anticonceptivos Femeninos/uso terapéutico , Antagonistas de Estrógenos/uso terapéutico , Femenino , Humanos , Factores Inmunológicos/uso terapéutico , Levonorgestrel/uso terapéutico , Dolor Pélvico/etiología , Calidad de Vida , Receptores de Progesterona/antagonistas & inhibidores
12.
Oncogene ; 6(6): 917-28, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1906159

RESUMEN

We have previously described two cellular immediate-early genes, Egr-1 (mouse) and EGR2 (human) that encode zinc finger proteins. Here we report the characterization of a new member of the Egr family referred to as EGR3 (human). This cDNA clone was isolated using low stringency hybridization with the zinc finger domain of Egr-1. The EGR3 cDNA sequence predicts a 387 amino acid (a.a.) protein containing three Cys2-His2 zinc fingers nearly identical to those of Egr-1 and EGR2. This similarity has a functional consequence: EGR3 can activate transcription of a CAT gene linked to the sequence CGCCCCCGC, a cis element which is a target for Egr-1 and EGR2. We show that EGR3 is an immediate-early growth response gene induced by mitogenic stimulation of rodent and human fibroblasts and a monkey kidney epithelial cell line. The EGR3 gene has a single intron and maps to chromosome 8 at bands p21-23.


Asunto(s)
Genes Reguladores/genética , Proteínas Inmediatas-Precoces , Regiones Promotoras Genéticas/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Mapeo Cromosómico , ADN/análisis , ADN/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteína 1 de la Respuesta de Crecimiento Precoz , Proteína 3 de la Respuesta de Crecimiento Precoz , Fibroblastos/metabolismo , Haplorrinos , Humanos , Datos de Secuencia Molecular , Factores de Transcripción/metabolismo , Transcripción Genética/genética , Dedos de Zinc/genética
14.
Indian J Exp Biol ; 27(12): 1109-10, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2633975

RESUMEN

A series of synthetic terpenoid diethers, with known mosquito development inhibitory activity, were tested for cyclopcidal activity against adult cyclops, Mesocyclops leuckarti. Four among these exhibited promising activity comparable to that of the conventional organophosphate, temephos, thus providing for the first time a possible reserve arsenal for the control of the guineaworm disease vector.


Asunto(s)
Crustáceos/efectos de los fármacos , Hormonas Juveniles/farmacología , Animales
15.
Indian J Physiol Pharmacol ; 39(2): 135-9, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7649601

RESUMEN

Peak expiratory flow rates (PEFR) were measured in 60 pregnant women aged 20-28 years (average 24 yrs) height between 130-160 cm (average 154.5 cm), each month beginning from 3rd month of gestation and also 8-10 weeks postpartum using, Wright's Peak Flow Meter. The PEFR declined from 329.12 +/- 4.40 lpm in 3rd month to 286.22 +/- 3.81 lpm in 9th month of gestation and increased to 347.86 +/- 2.93 lpm in postpartal period. A similar, declining trend is also observed in other Indian studies. However, the values are lower than those observed in Europeans. Also no change in PEFR during pregnancy was observed in an European study. The PEFR in our study regressed at a rate of 6.68 lpm/month of gestation and 5.49 lpm/kg increase in weight throughout pregnancy. The correlation with forced vital capacity (FVC) and forced expiratory volume in first second (FEV1) is non-significant throughout pregnancy. The anaemic pregnant women showed lower PEFR when compared with PEFR of nonanaemic pregnant women, but showed a similar declining trend throughout pregnancy.


Asunto(s)
Ápice del Flujo Espiratorio/fisiología , Embarazo/fisiología , Adulto , Anemia/fisiopatología , Estatura/fisiología , Peso Corporal/fisiología , Estudios de Cohortes , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , India , Periodo Posparto/fisiología , Complicaciones Hematológicas del Embarazo/fisiopatología , Análisis de Regresión , Capacidad Vital/fisiología
16.
Indian J Physiol Pharmacol ; 38(2): 129-32, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8063358

RESUMEN

The study deals with evaluation of pulmonary function status in fifty normal pregnant women tested monthly. The parameters studied were Vital Capacity (VC) Forced Vital Capacity (FVC) and Forced Expiratory Volume in 1st second (FEV1) using Vitalograph Spirometer; tidal volume (VT), inspiratory capacity (IC) and expiratory reserve volume (ERV) using Expirograph and resting minute ventilation (VE) using Tissot's spirometer. Control values were obtained in the same subject 8-10 weeks after delivery. The increase seen in VT, VE and IC was very highly significant. The small increment in frequency of respiration is significant and the declining trend observed in ERV is very highly significant. VC and FVC were maintained by the rise in IC and a concomitant fall in ERV. Rise in VC is attributed mainly to rise in VT than rise in frequency. The results suggest that though pulmonary function is altered during pregnancy, it is not compromised and hence does not induce any mechanical stress on the respiratory efficiency of the pregnant woman.


Asunto(s)
Pulmón/fisiología , Embarazo/fisiología , Pruebas de Función Respiratoria , Mecánica Respiratoria , Adulto , Femenino , Humanos , Estudios Longitudinales
17.
Indian J Physiol Pharmacol ; 38(1): 34-8, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8132241

RESUMEN

This study presents a composite picture of haemoglobin (Hb), serum level of iron (SI), total iron binding capacity (TIBC) and percent iron saturation of transferrin in women during different trimesters of pregnancy and postpartum period. The results were correlated with age and parity. A total of 75 subjects, 15 from each trimester and 15 postpartal, were studied and compared with 15 nonpregnant normal subjects. Signs of increased iron demand, increased iron turnover and obvious iron deficiency, were demonstrated throughout pregnancy, by decrease in haemoglobin, SI, percent iron saturation of transferrin and increased TIBC; especially in older age group and multigravidae. SI, TIBC and percent iron saturation of transferrin are more sensitive indices of iron status and provide us an opportunity to replenish iron stores of an iron deficient pregnant mother at an earlier date thus preventing anaemia.


Asunto(s)
Hierro/sangre , Periodo Posparto/sangre , Embarazo/sangre , Transferrina/metabolismo , Adolescente , Adulto , Envejecimiento/sangre , Proteínas Portadoras/sangre , Femenino , Hemoglobinas/metabolismo , Humanos , Deficiencias de Hierro , Proteínas de Unión a Hierro , Proteínas de Unión a Transferrina
18.
J Commun Dis ; 25(1): 30-5, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7912248

RESUMEN

Biological activity of saturated diethers viz. 1-benzyloxy/phenoxy-8-alkoxy and 1-alkoxy-8-benzyloxy-3,7-dimethyl-1, 8-octanes (IIa-IIq) prepared from Geraniol, were studied on three mosquito species and the bug Dysdercus koenigii. These diethers exhibited oviposition deterrent and developmental inhibition activities of greater magnitudes than the compounds based on citronellol reported in Part I of this paper. Some of these new compounds inhibit development of mosquitoes at 0.05 ppm and deter oviposition at 0.05 per cent doses. Tests were extended to field simulated conditions in selected cases.


Asunto(s)
Culicidae/crecimiento & desarrollo , Insectos Vectores/crecimiento & desarrollo , Octanos/farmacología , Oviposición/efectos de los fármacos , Éteres Fenílicos/farmacología , Terpenos , Monoterpenos Acíclicos , Animales , Culicidae/clasificación , Estudios de Evaluación como Asunto , Femenino , Insectos Vectores/clasificación , Masculino , Terpenos/química
19.
J Commun Dis ; 23(2): 118-22, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1682357

RESUMEN

New series of compounds starting from common terpenoids (Geraniol, citronellol) have been examined for biological activity on mosquito larvae. Many of these exhibited development disruption on eggs as well larvae. Some also affected adult oviposition behaviour. Developmental disturbances were classified as JH type by inducing typical metamorphosis inhibition in Dysdercus koenigii in the standard Hemipteran JH bioassay. Where indicated simulated field trials were also undertaken. This report describes results of bioevaluation of the citronellol based compounds. The results indicate that these show multifarious activity against mosquitoes but at relatively high doses, suggesting that exploration of further structural variety is needed before truly promising analogues can be obtained.


Asunto(s)
Culicidae/efectos de los fármacos , Diterpenos/farmacología , Inhibidores de Crecimiento/farmacología , Insectos Vectores/efectos de los fármacos , Monoterpenos , Terpenos/farmacología , Monoterpenos Acíclicos , Animales , Femenino , Larva/efectos de los fármacos , Óvulo/efectos de los fármacos , Óvulo/crecimiento & desarrollo
20.
Indian J Med Microbiol ; 29(4): 389-94, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22120800

RESUMEN

OBJECTIVE: The purpose of our study was to compare various laboratory diagnostic methods, namely histopathological examination, Ziehl-Neelsen (ZN) stain, AFB culture by conventional Lowenstein-Jensen (LJ) method and fluorescence-based mycobacterial growth indicator tube (MGIT) technique and polymerase chain reaction (PCR) in clinically suspected cases of tubercular lymphadenitis. MATERIALS AND METHODS: A total of 65 lymph nodes biopsied from patients clinically suspected of having tubercular lymph nodes were included. Specimens were processed for AFB culture after NaOH-NALC concentration and inoculation on LJ medium and using the MGIT system. PCR was performed on all specimens using a commercial nested PCR kit targeting IS6110 insertion element of Mycobacterium tuberculosis complex. All lymph node specimens were subjected to histopathological examination. RESULTS: Of the 65 lymph nodes, 37 (56.9%) were positive on MGIT culture and 45 (69.2%) were positive by PCR. Histopathology showed maximum sensitivity (96%) but with compromised specificity (78.5%). PCR showed 90.1% sensitivity and 100% specificity. The mean turnaround time for mycobacterial growth in smear negative specimens was 30 days determined by LJ and 20 days by MGIT techniques. CONCLUSION: PCR is a rapid and useful method for diagnosis of TB lymphadenitis and definitely increases the positive predictive value of a positive histopathology report. MGIT is better than LJ culture as regards time to positivity and higher yield.


Asunto(s)
Técnicas Bacteriológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Tuberculosis Ganglionar/diagnóstico , Adolescente , Adulto , Anciano , Biopsia , Niño , Preescolar , Femenino , Histocitoquímica , Humanos , Lactante , Ganglios Linfáticos/microbiología , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/genética , Sensibilidad y Especificidad , Adulto Joven
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