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1.
J Obstet Gynaecol ; 31(4): 304-6, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21534750

RESUMEN

This is a retrospective cohort study to establish the effect of induction of labour (IOL) on the mode of delivery for term pregnancy. Studied population included 11,660 deliveries and out of these, 8,314 were normal vaginal deliveries; 1,775 instrumental deliveries and 1,571 emergency caesarean sections. The frequency of IOL was 23.6%. A univariate analysis was carried out to establish a relationship between IOL and mode of delivery. The multivariable regression analysis was carried out to adjust this relationship for parity, age, gestational age, epidural analgesia and birth weight. IOL at term lowered the risk of instrumental delivery (p=0.009) and had no influence on the rate of caesarean section (p=0.861). Hence, the study demonstrates that women in whom induction is decided upon, the instrumental delivery and caesarean section rate is not any higher than in the group where a spontaneous labour is awaited.


Asunto(s)
Parto Obstétrico/estadística & datos numéricos , Trabajo de Parto Inducido , Adulto , Cesárea/estadística & datos numéricos , Extracción Obstétrica/estadística & datos numéricos , Femenino , Humanos , Embarazo , Análisis de Regresión , Estudios Retrospectivos
2.
Math Biosci Eng ; 18(4): 3274-3290, 2021 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-34198385

RESUMEN

In this work, power-series solutions of compartmental epidemiological models are used to provide alternate methods to solve the corresponding systems of nonlinear differential equations. A simple and classical SIR compartmental model is considered to reveal clearly the idea of our approach. Moreover, a SAIRP compartmental model is also analyzed by using the same methodology, previously applied to the COVID-19 pandemic. Numerical experiments are performed to show the accuracy of this approach.


Asunto(s)
COVID-19 , Pandemias , Humanos , SARS-CoV-2
3.
Br J Cancer ; 102(8): 1201-6, 2010 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-20354525

RESUMEN

BACKGROUND: This study aimed to show the longitudinal use of routinely collected clinical data from history and ultrasound evaluation of the endometrium in developing an algorithm to predict the risk of endometrial carcinoma for postmenopausal women presenting with vaginal bleeding. METHODS: This prospective study collected data from 3047 women presenting with postmenopausal bleeding. Data regarding the presence of risk factors for endometrial cancer was collected and univariate and multivariate analyses were performed. RESULTS: Age distribution ranged from 35 to 97 years with a median of 59 years. A total of 149 women (5% of total) were diagnosed with endometrial carcinoma. Women in the endometrial cancer group were significantly more likely to be older, have higher BMI, recurrent episodes of bleeding, diabetes, hypertension, or a previous history of breast cancer. An investigator best model selection approach was used to select the best predictors of cancer, and using logistic regression analysis we created a model, 'Norwich DEFAB', which is a clinical prediction rule for endometrial cancer. The calculated Norwich DEFAB score can vary from a value of 0 to 9. A Norwich DEFAB value equal to or greater than 3 has a positive predictive value (PPV) of 7.78% and negative predictive value (NPV) of 98.2%, whereas a score equal to or greater than 5 has a PPV of 11.9% and NPV of 97.8%. CONCLUSION: The combination of clinical information with our investigation tool for women with postmenopausal vaginal bleeding allows the clinician to calculate a predicted risk of endometrial malignancy and prioritise subsequent clinical investigations.


Asunto(s)
Neoplasias Endometriales/diagnóstico , Medición de Riesgo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Neoplasias Endometriales/diagnóstico por imagen , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Riesgo , Sensibilidad y Especificidad , Ultrasonografía , Hemorragia Uterina/etiología
4.
J Theor Biol ; 257(1): 17-26, 2009 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-19056401

RESUMEN

In this paper we present a study of classification of the 20 amino acids via a fuzzy clustering technique. In order to calculate distances among the various elements we employ two different distance functions: the Minkowski distance function and the NTV metric. In the clustering procedure we take into account several physical properties of the amino acids. We examine the effect of the number and nature of properties taken into account to the clustering procedure as a function of the degree of similarity and the distance function used. It turns out that one should use the properties that determine in the more important way the behavior of the amino acids and that the use of the appropriate metric can help in defining the separation into groups.


Asunto(s)
Aminoácidos/clasificación , Lógica Difusa , Secuencia de Aminoácidos , Aminoácidos/química , Animales , Química Física , Análisis por Conglomerados , Biología Computacional/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Químicos , Datos de Secuencia Molecular , Peso Molecular
5.
Arch Gynecol Obstet ; 279(3): 419-21, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18642011

RESUMEN

CASE REPORT: A woman with a previous hysterectomy and bilateral salpingo-oophorectomy for endometriosis presented with painless vaginal bleeding. Imaging revealed a heterogeneous soft tissue pelvic mass suggestive of a malignant neoplastic lesion. Radical surgery was performed including excision of the pelvic mass and anterior resection of the sigmoid colon. Histopathology revealed endometriosis. CONCLUSION: The risk of malignant transformation and the difficulty in achieving a preoperative diagnosis make radical surgery inevitable in the management of recurrent endometriosis. The use of hormone replacement therapy after bilateral salpingo-oophorectomy for endometriosis remains controversial and requires careful counseling about recurrence and close follow-up.


Asunto(s)
Endometriosis/diagnóstico , Neoplasias Pélvicas/diagnóstico , Adulto , Diagnóstico Diferencial , Endometriosis/patología , Endometriosis/cirugía , Femenino , Humanos , Histerectomía , Imagen por Resonancia Magnética , Neoplasias Pélvicas/patología , Neoplasias Pélvicas/cirugía , Recurrencia , Tomografía Computarizada por Rayos X
6.
Microbiol Mol Biol Rev ; 62(2): 504-44, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9618450

RESUMEN

The moderately halophilic heterotrophic aerobic bacteria form a diverse group of microorganisms. The property of halophilism is widespread within the bacterial domain. Bacterial halophiles are abundant in environments such as salt lakes, saline soils, and salted food products. Most species keep their intracellular ionic concentrations at low levels while synthesizing or accumulating organic solutes to provide osmotic equilibrium of the cytoplasm with the surrounding medium. Complex mechanisms of adjustment of the intracellular environments and the properties of the cytoplasmic membrane enable rapid adaptation to changes in the salt concentration of the environment. Approaches to the study of genetic processes have recently been developed for several moderate halophiles, opening the way toward an understanding of haloadaptation at the molecular level. The new information obtained is also expected to contribute to the development of novel biotechnological uses for these organisms.


Asunto(s)
Bacterias Aerobias/genética , Bacterias Aerobias/fisiología , Cloruro de Sodio , Adaptación Biológica/genética , Adaptación Biológica/fisiología , Bacterias Aerobias/crecimiento & desarrollo , Bacterias Aerobias/metabolismo , Biodegradación Ambiental , Ecología , Microbiología del Suelo , Microbiología del Agua
7.
J Inequal Appl ; 2017(1): 167, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28775658

RESUMEN

A representation of [Formula: see text]-Bernstein polynomials in terms of [Formula: see text]-Jacobi polynomials is obtained.

8.
Math Biosci ; 269: 94-103, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26361287

RESUMEN

The unsteady flow characteristics of blood in a catheterized overlapping stenosed artery are analyzed in presence of body acceleration and magnetic field. The stenosed arterial segment is modeled as a rigid constricted tube. An improved shape of stenosis in the realm of the formulation of the arterial narrowing caused by atheroma is integrated in the present study. The catheter inside the artery is approximated by a thin rigid tube of small radius while the streaming blood in the artery is characterized by the Carreau model. Employing mild stenosis condition, the governing equation of the flow is derived which is then solving numerically using finite difference scheme. The variation of axial velocity, flow rate, resistance impendence and wall shear stress is shown graphically for various parameters of interest. The flow patterns illustrating the global behavior of blood are also presented.


Asunto(s)
Aterosclerosis/fisiopatología , Modelos Cardiovasculares , Simulación por Computador , Hemodinámica , Hemorreología , Humanos , Conceptos Matemáticos , Flujo Pulsátil
9.
Obstet Gynecol ; 95(1): 111-4, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10636512

RESUMEN

OBJECTIVE: To assess the effects on lipid and lipoprotein levels of a combination therapy of matrix patch and oral sequential dydrogesterone. METHODS: The lipid effects of transdermal estradiol (E2) (80 microg/day continuously) and oral dydrogesterone (10 mg from days 15-28 of each cycle) were assessed in a multicenter, prospective, open, baseline-controlled study. Subjects were 42 healthy, postmenopausal women who had not had hysterectomies. Fasting blood samples were taken at baseline, day 14 of cycle 3 (estrogen alone), and day 25 of cycle 6 (estrogen and progestogen). The main outcome measures were changes from baseline in total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides after six cycles. RESULTS: Thirty-six subjects completed six cycles and in the 28 with complete data, HDL cholesterol increased by 10.6% from 65.25 to 72.2 mg/dL (95% confidence interval [CI] 2.32, 11.58, P = .005) and LDL cholesterol fell by 5.1% from 130.9 to 124.3 mg/dL (95% CI 13.9, 1.16, P = .07). There was a nonsignificant decrease in LDL cholesterol from 130.9 at baseline to 124.3 mg/dL at 6 months and in triglycerides from 110.6 to 107.1 mg/dL. CONCLUSION: Sequential treatment with transdermal E2 and oral dydrogesterone increased HDL cholesterol, without the accompanying increase in triglycerides that occurs with oral estrogen replacement therapy.


Asunto(s)
HDL-Colesterol/sangre , LDL-Colesterol/sangre , Didrogesterona/farmacología , Estradiol/farmacología , Terapia de Reemplazo de Estrógeno , Congéneres de la Progesterona/farmacología , Adulto , Apolipoproteínas/sangre , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos
10.
FEMS Microbiol Lett ; 183(1): 67-71, 2000 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-10650204

RESUMEN

Extracellular amylase production by the moderate halophile Halomonas meridiana was optimized and the enzyme was characterized biochemically. The highest amylase production was achieved by growing H. meridiana cultures in media with 5% salts and starch, in the absence of glucose until the end of the exponential phase. The amylase exhibited maximal activity at pH 7.0, being relatively stable in alkaline conditions. Optimal temperature and salinity for activity were 37 degrees C and 10% NaCl, respectively. Moreover, activity at salinity as high as 30% salts was detected. Maltose and maltotriose were the main end products of starch hydrolysis, indicating an alpha-amylase activity.


Asunto(s)
Halomonas/enzimología , Halomonas/crecimiento & desarrollo , alfa-Amilasas/metabolismo , Medios de Cultivo , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Hidrólisis , Cloruro de Sodio/farmacología , Temperatura
11.
FEMS Microbiol Lett ; 154(1): 45-51, 1997 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-9297819

RESUMEN

A native promoter located on the cryptic plasmid pHE1 from the moderate halophile Halomonas elongata was identified employing a promoterless ice nucleation gene inaZ of Pseudomonas syringae by direct subcloning and assaying for ice nucleation activity. The presence of the promoter was verified by inserting the corresponding intact or deleted pHE1 fragment in the promoter analysis vector pKK232-8 upstream of the promoterless cat or inaZ gene. Only constructs carrying the intact pHE1 fragment gave CAT phenotype (chloramphenicol resistance) or ice nucleation activity, respectively. Comparative evaluation of the sequence analysis data of the intact and deleted fragment suggested the localization of an Escherichia coli-type promoter region.


Asunto(s)
Vectores Genéticos , Halobacteriaceae/genética , Plásmidos , Regiones Promotoras Genéticas , Pseudomonas/genética , Secuencia de Bases , ADN Bacteriano/genética , Escherichia coli/genética , Genes Reporteros , Datos de Secuencia Molecular
12.
J Neurol Sci ; 177(1): 18-23, 2000 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-10967178

RESUMEN

The formation and rupture of aneurysms is a significant medical problem, but is not clearly understood. Most intracranial aneurysm are located in the circle of Willis. We consider a nonlinear mathematical model that simulates the blood flow inside the aneurysm, one of the relevant factors in the evolution of an aneurysm. Different techniques from nonlinear analysis are used in order to obtain, from the model, several consequences that would help to understand some medical aspects of aneurysms of the circle of Willis.


Asunto(s)
Círculo Arterial Cerebral/fisiología , Aneurisma Intracraneal , Modelos Cardiovasculares , Dinámicas no Lineales , Humanos , Aneurisma Intracraneal/fisiopatología
13.
Syst Appl Microbiol ; 21(4): 487-97, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9924816

RESUMEN

The ectoine synthesis genes of the moderately halophilic bacterium Halomonas elongata DSM 3043 have been precisely located in a 2.8-kb EcoRI region of a cosmid clone previously isolated (CANOVAS, D., VARGAS, C., IGLESIAS-GUERRA, F., CSONKA, L. N., RHODES, D., VENTOSA, A., NIETO, J. J.: Isolation and characterization of salt-sensitive mutants of the moderate halophile Halomonas elongata and cloning of the ectoine synthesis genes. J. Biol. Chem. 272, 25794-25801, 1997). This region was sequenced and three open reading frames were found corresponding to the genes ectA (encoding the diaminobutyric acid acetyl transferase), ectB (encoding the diaminobutyric acid aminotransferase) and ectC (encoding the ectoine synthase). These three genes were able to restore the salt tolerance of two H. elongata mutants defective in the synthesis of ectoine (strains CHR62 and CHR63). However, the H. elongata ectoine synthesis genes did not confer to Escherichia coli the ability to synthesize ectoine. Transposon insertion in the salt-sensitive mutant strain CHR63 was exactly mapped within the ectC gene. Moreover, sequences homologous to the H. elongata ect region have been found in a number of moderately halophilic bacteria belonging to the genera Halomonas and Chromohalobacter.


Asunto(s)
Aminoácidos Diaminos/genética , Genes Bacterianos , Halobacterium/genética , Acetiltransferasas/genética , Secuencia de Aminoácidos , Aminoácidos Diaminos/biosíntesis , Secuencia de Bases , Clonación Molecular , Elementos Transponibles de ADN/genética , Escherichia coli/química , Escherichia coli/genética , Halobacterium/metabolismo , Datos de Secuencia Molecular , Mutación , Sistemas de Lectura Abierta , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transaminasas/genética
14.
Syst Appl Microbiol ; 22(4): 520-9, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10794139

RESUMEN

The mobilization (mob) region of the non-self transmissible 4.2-kb plasmid pHE1 from the moderately halophilic bacterium Halomonas elongata ATCC 33174 has been identified and characterized. Analysis of the sequence revealed the presence of four open reading frames (mobCABD) which show a complex organization with two of them (mobB and mobD) entirely overlapped by a third (mobA). The deduced proteins appeared to have a high degree of homology to Mob proteins of CoIE1 and closely related plasmids. To assess the functionality of the mob region, the hybrid vector pHS134 was constructed, consisting of the complete plasmid pHEI, the E. coli vector pKS(-) and a streptomycin-resistance gene for positive selection in Halomonas. Vector pHS134 was found to be mobilizable from E. coli to H. elongata assisted by pRK600. Upstream of the mob genes, an oriT region with a putative nick sequence highly homologous to that of CoIE1 plasmids was identified. To our knowledge, this is the first mobilizable plasmid found in moderate halophiles. This property, together with its small size, the availability of its complete sequence, and its broad host range in moderately halophilic strains, makes pHE1 a good candidate for the construction of cloning and expression vectors for these extremophiles.


Asunto(s)
Proteínas Bacterianas/genética , Halomonas/genética , Plásmidos/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Halomonas/crecimiento & desarrollo , Datos de Secuencia Molecular , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
15.
Eur J Gynaecol Oncol ; 23(2): 111-2, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12013103

RESUMEN

Risk factors for squamous cell vulval cancer (SCC) remain unclear though there have been associations with lichen sclerosis, smoking, and vulval intraepithelial neoplasia (VIN). We studied 191 patients who had been referred to the vulval clinic at the Royal Free Hospital and who had both blood group and histopathology results available. Seventy-two percent of patients with SCC and non-neoplastic epithelial disorders of the vulva (NNEDV) were found to be in blood group A with only 17% in blood group O. Those with SCC associated with VIN had only 30% in blood group A with 50% in blood group O. The control population showed that 38% of the population were in blood group A and 43% were in blood group O. Our results suggest that blood group A is prevalent in patients with SCC associated with NNEDV but not in those women with squamous vulval cancer and associated VIN.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Carcinoma in Situ/sangre , Carcinoma in Situ/etiología , Neoplasias de la Vulva/sangre , Neoplasias de la Vulva/etiología , Femenino , Humanos , Persona de Mediana Edad , Factores de Riesgo , Reino Unido
17.
J Appl Microbiol ; 100(1): 98-107, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16405689

RESUMEN

AIMS: To investigate the catabolism of ectoine and hydroxyectoine, which are the major compatible solutes synthesized by Chromohalobacter salexigens. METHODS AND RESULTS: Growth curves performed in M63 minimal medium with low (0.75 mol l(-1) NaCl), optimal (1.5 mol l(-1) NaCl) or high (2.5 mol l(-1) NaCl) salinity revealed that betaine and ectoines were used as substrate for growth at optimal and high salt. Ectoine transport was maximal at optimal salinity, and showed 3- and 1.5-fold lower values at low and high salinity respectively. The salt-sensitive ectA mutant CHR62 showed an ectoine transport rate 6.8-fold higher than that of the wild type. Incubation of C. salexigens in a mixture of glucose and ectoine resulted in a biphasic growth pattern. However, CO(2) production due to ectoine catabolism was lower, but not completely abolished, in the presence of glucose. When used as the sole carbon source, glycine betaine effectively inhibited ectoine and hydroxyectoine synthesis at any salinity. CONCLUSIONS: The catabolic pathways for ectoine and hydroxyectoine in C. salexigens operate at optimal and high (although less efficiently) salinity. Endogenous ectoine(s) may repress its own transport. Ectoine utilization was only partially repressed by glucose. Betaine, when used as carbon source, suppresses synthesis of ectoines even under high osmolarity conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is a previous step to the subsequent isolation and manipulation of the catabolic genes, so as to generate strains with enhanced production of ectoine and hydroxyectoine.


Asunto(s)
Aminoácidos Diaminos/farmacocinética , Carbono/metabolismo , Halomonadaceae/metabolismo , Betaína/farmacocinética , Transporte Biológico/fisiología , Medios de Cultivo , Ingestión de Energía/fisiología , Glucosa/metabolismo , Halomonadaceae/crecimiento & desarrollo , Ósmosis/fisiología , Cloruro de Sodio/metabolismo , Soluciones/metabolismo
18.
World J Microbiol Biotechnol ; 11(1): 85-94, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24414413

RESUMEN

Halophilic microorganisms are found as normal inhabitants of highly saline environments and thus are considered extremophiles. They are mainly represented, but not exclusively, by the halobacteria (extremely halophilic aerobic Archaea), the moderate halophiles (Bacteria and some methanogens) and several eukaryotic algae. These extremophilic microorganisms are already used for some biotechnological processes, for example halobacteria are used for the production of bacteriorhodopsin, and the alga Dunaliella is used in the commercial production of ß-carotene. Several other present or potential applications of halophiles are reviewed, including the production of polymers (polyhydroxyalcanoates and polysaccharides), enzymes, and compatible solutes, and the use of these extremophiles in enhanced oil recovery, cancer detection, drug screening and the biodegradation of residues and toxic compounds.

19.
Appl Environ Microbiol ; 53(5): 1199-202, 1987 May.
Artículo en Inglés | MEDLINE | ID: mdl-16347350

RESUMEN

Sixty-eight halobacteria, including both culture collection strains and fresh isolates from widely differing geographical areas, were tested for susceptibility to arsenate, cadmium, chromium, cobalt, copper, lead, mercury, nickel, silver, and zinc ions by an agar dilution technique. The culture collection strains showed different susceptibilities, clustering into five groups. Halobacterium mediterranei and Halobacterium volcanii were the most metal tolerant, whereas Haloarcula californiae and Haloarcula sinaiiensis had the highest susceptibilities of the culture collection strains. Different patterns of metal susceptibility were found for all the halobacteria tested, and there was a uniform susceptibility to mercury and silver. All strains tested were multiply metal tolerant.

20.
Plasmid ; 34(3): 157-64, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8825368

RESUMEN

Shuttle vectors useful for the genetic manipulation of several moderately halophilic bacteria have been constructed. These vectors are based on the minimal replicon of pCM1, a cryptic plasmid from Chromohalobacter marismortui, combined with the useful properties of pUC18 plasmid (i.e., small size, high copy number, multiple cloning sites, lacZ fragment), as well as with the trimethoprim resistance gene as a selection marker for moderate halophiles. These vectors can be efficiently transferred by RP4-mediated conjugation from Escherichia coli to the moderate halophiles Chromohalobacter marismortui, Deleya halophila, Halomonas elongata, Halomonas subglaciescola, and Volcaniella eurihalina.


Asunto(s)
Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/genética , Vectores Genéticos/genética , Bacterias Aerobias Gramnegativas/genética
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