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1.
Eur J Nutr ; 59(1): 309-325, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30805695

RESUMEN

BACKGROUND: Brown seaweeds are known to be a rich source of fiber with the presence of several non-digestible polysaccharides including laminarin, fucoidan and alginate. These individual polysaccharides have previously been shown to favorably alter the gut microbiota composition and activity albeit the effect of the collective brown seaweed fiber component on the microbiota remains to be determined. METHODS: This study investigated the effect of a crude polysaccharide-rich extract obtained from Laminaria digitata (CE) and a depolymerized CE extract (DE) on the gut microbiota composition and metabolism using an in vitro fecal batch culture model though metagenomic compositional analysis using 16S rRNA FLX amplicon pyrosequencing and short-chain fatty acid (SCFA) analysis using GC-FID. RESULTS: Selective culture analysis showed no significant changes in cultured lactobacilli or bifidobacteria between the CE or DE and the cellulose-negative control at any time point measured (0, 5, 10, 24, 36, 48 h). Following metagenomic analysis, the CE and DE significantly altered the relative abundance of several families including Lachnospiraceae and genera including Streptococcus, Ruminococcus and Parabacteroides of human fecal bacterial populations in comparison to cellulose after 24 h. The concentrations of acetic acid, propionic acid, butyric acid and total SCFA were significantly higher for both the CE and DE compared to cellulose after 10, 24, 36 and 48 h fermentation (p < 0.05). Furthermore, the acetate:propionate ratio was significantly reduced (p < 0.05) for both CD and DE following 24, 36 and 48 h fermentation. CONCLUSION: The microbiota-associated metabolic and compositional changes noted provide initial indication of putative beneficial health benefits of L. digitata in vitro; however, research is needed to clarify if L. digitata-derived fiber can favorably alter the gut microbiota and confer health benefits in vivo.


Asunto(s)
Colon/metabolismo , Microbioma Gastrointestinal/efectos de los fármacos , Laminaria/metabolismo , Laminaria/microbiología , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Colon/microbiología , Heces/microbiología , Microbioma Gastrointestinal/fisiología , Humanos , Técnicas In Vitro , Modelos Biológicos , Extractos Vegetales/metabolismo , Polisacáridos/metabolismo
2.
Mar Drugs ; 14(3)2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26999166

RESUMEN

Seaweeds are a large and diverse group of marine organisms that are commonly found in the maritime regions of the world. They are an excellent source of biologically active secondary metabolites and have been shown to exhibit a wide range of therapeutic properties, including anti-cancer, anti-oxidant, anti-inflammatory and anti-diabetic activities. Several Asian cultures have a strong tradition of using different varieties of seaweed extensively in cooking as well as in herbal medicines preparations. As such, seaweeds have been used to treat a wide variety of health conditions such as cancer, digestive problems, and renal disorders. Today, increasing numbers of people are adopting a "westernised lifestyle" characterised by low levels of physical exercise and excessive calorific and saturated fat intake. This has led to an increase in numbers of chronic Non-communicable diseases (NCDs) such as cancer, cardiovascular disease, and diabetes mellitus, being reported. Recently, NCDs have replaced communicable infectious diseases as the number one cause of human mortality. Current medical treatments for NCDs rely mainly on drugs that have been obtained from the terrestrial regions of the world, with the oceans and seas remaining largely an untapped reservoir for exploration. This review focuses on the potential of using seaweed derived bioactives including polysaccharides, antioxidants and fatty acids, amongst others, to treat chronic NCDs such as cancer, cardiovascular disease and diabetes mellitus.


Asunto(s)
Medicina Tradicional de Asia Oriental , Algas Marinas/metabolismo , Animales , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedad Crónica , Diabetes Mellitus/tratamiento farmacológico , Humanos , Neoplasias/tratamiento farmacológico , Metabolismo Secundario
3.
Health Promot Pract ; 17(4): 596-600, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27091609

RESUMEN

The Maryland Local Overdose Fatality Review Teams (LOFRTs) are multiagency, multidisciplinary teams that critically analyze individual cases of drug overdose in their jurisdictions to identify preventable risk factors and missed opportunities for intervention, and to make policy and programmatic recommendations to prevent future overdose deaths. Three Maryland LOFRTs were first piloted in early 2014, and became established in law in May of the same year. LOFRTs provide unique opportunities for enhanced interagency collaboration and locally driven prevention efforts. This study describes the process of establishing LOFRTs in Maryland. The experiences and information regarding LOFRTs may help counties in other states combat the growing problem of deaths by drug overdose.


Asunto(s)
Sobredosis de Droga/mortalidad , Sobredosis de Droga/prevención & control , Relaciones Interinstitucionales , Relaciones Interprofesionales , Conducta Cooperativa , Humanos , Liderazgo , Maryland/epidemiología , Factores de Riesgo
4.
J Med Biogr ; : 9677720241240263, 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39434551

RESUMEN

Albert Sharman was a Glasgow-born and based gynaecologist who pioneered research into infertility and the diagnosis of pregnancy using new techniques of investigation and treatment, many of his own design. His Fertility Clinic, opened in 1931, was the first in Britain, and became a model for those that followed. Working at Glasgow's Royal Samaritan Hospital for Women, he published widely in the medical press, especially the British Medical Journal and the Lancet, and he authored and co-edited several books, some aimed at a medical audience while others sought to explain complex issues surrounding puberty, fertility and the menopause to the general public.

5.
J Med Biogr ; 31(1): 21-28, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33884892

RESUMEN

Dr Hetty Ockrim was a general practitioner in an inner-city Glasgow district for 43 years, before retiring in 1989. This paper looks at her career and her legacy through the pioneering oral history study she undertook, on retirement, with former patients, and the 'Letters to No-one' written at the time of her retirement but only discovered at the time of her death.

6.
Am J Phys Anthropol ; 149 Suppl 55: 114-31, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23124506

RESUMEN

Both the United States and the United Kingdom experienced a transformation in the science of physical anthropology from the period before World War II until the post-war period. In the United States, Sherwood L. Washburn is credited with being a leading figure in this transformation. In the United Kingdom, two individuals were instrumental in bringing about a similar change in the profession. These were Joseph S. Weiner at the University of Oxford and Nigel Barnicot at the University of London, with Weiner playing the principal role as leader in what Washburn called the "New Physical Anthropology," that is, the application of evolutionary theory, the de-emphasis on race classification, and the application of the scientific method and experimental approaches to problem solving. Weiner's contributions to physical anthropology were broad-based--climatic and work physiology, paleoanthropology, and human variation--in what became known as human biology in the U.K. and human adaptability internationally. This biographical essay provides evidence for the significant influence of J.S. Weiner on the post-war development of human biology (biological or physical anthropology) inthe U.K.


Asunto(s)
Antropología Física/historia , Biología/historia , Historia del Siglo XX , Humanos , Sudáfrica , Reino Unido
7.
J Med Biogr ; : 9677720221135122, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36420743

RESUMEN

Ernest Abraham Hart (26 June 1835-7 January 1898) was the long-time editor of the British Medical Journal. He held strong opinions, and was often controversial but his views generally prevailed. He was born into a Jewish family in London and was educated at the City of London School. He studied medicine at the St George's Hospital School of Medicine and specialised in diseases of the eye. His medical journalism began with The Lancet in 1857 and in August 1866, he was appointed editor of the British Medical Journal taking it, in his decades of leadership, from a small publication to a significant scientific journal increasing the British Medical Association membership substantially. Julia Frankau's novel of scandal, Dr Phillips: A Maida Vale Idyll (1887) published under the pseudonym of Frank Danby, has a leading character, Dr Phillips, thought to be modelled on Ernest Hart and who murders his wife reviving speculation about the death of Hart's first wife from accidental poisoning.

8.
Langmuir ; 27(1): 187-95, 2011 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-21141900

RESUMEN

Nitrogen adsorption isotherms of silicas and other oxidic materials are distorted by the presence of micropore adsorption and capillary condensation. This distortion affects the determination of the specific area of the material, depending on the chosen calculation procedure. Correction of the initial (total) isotherm for micropore capacity decreases or eliminates this source of error to give a useful estimate of the external surface area. In the present work, 26 silica-based adsorbent materials were studied to obtain total and external specific surface areas by the Brunauer-Emmett-Teller (BET), I-point, and α-plot procedures, using the micropore capacities from the α-plots to obtain the corrected (external) isotherms. Errors in the specific surface areas due to the presence of micropores are given by the equation ΔsA = 3.267 (m(2)/cm(3) STP) sV(mic), where sA is the specific surface area in m(2)/g and sV(mic) is the micropore capacity in cm(3) STP/g. A consistent set of conversion factors was obtained by which the external specific surface area obtained using one of these procedures can be converted, with part-per-thousand precision, to either of the others. Although the I-point procedure presents the advantage of not requiring a defined p/p(0) range, the α-plot procedure is recommended for routine determinations of external specific areas of silicas and other oxidic materials, except for cases in which the shapes of the adsorption isotherms of the sample and the reference differ significantly from one another in the p/p(0) range used for the determination.

9.
J Med Biogr ; 29(4): 195-201, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31684802

RESUMEN

Portugal exiled its Jews in 1497. In 1536, the Portuguese Inquisition began to persecute Jews who continued to practice their religion in secret. It became difficult for the secret Jews to leave Portugal, but small communities of emigres grew up around Europe, especially in London, Amsterdam and Salonica (Thessaloniki), and beyond. As the Portuguese Inquisition became more active in the early decades of the eighteenth-century, Jews, who had been accustomed to practising their religion in secret, while outwardly conforming to Catholicism, were again sought out for persecution. Philip De la Cour's parents escaped from Portugal and arrived in London around 1707 and his eventful life in London and Bath illustrates many of the aspects of eighteenth-century Jewish medical life.


Asunto(s)
Judíos , Médicos , Catolicismo , Humanos , Londres , Portugal
10.
J Chromatogr A ; 1191(1-2): 90-8, 2008 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-18243228

RESUMEN

To further extend our studies in the search for reversed phases with enhanced durability at high pH, zirconized silica has now been explored as an alternative support. The synthesis of the new stationary phases involves silanization of a zirconium-modified silica support with a C(18) trifunctional silane, followed by endcapping. The chromatographic properties of the C(18) phases based on zirconized silica are similar to their titanized silica counterparts. Accelerated high pH stability tests, using phosphate mobile phases and elevated temperature, have shown that the zirconized silica phases have promising advantages not only over similarly prepared non-metalized phases but also over titanized silica C(18) phases.


Asunto(s)
Cromatografía Líquida de Alta Presión/instrumentación , Silanos/síntesis química , Dióxido de Silicio/química , Circonio/química , Fenómenos Químicos , Química Física , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Espectrometría por Rayos X , Espectrofotometría Infrarroja
11.
Hist Psychiatry ; 19(74 Pt 2): 185-201, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19127838

RESUMEN

The Scottish psychiatrist R. D. Laing (1929-88) was one of the most influential but also one of the most controversial figures in twentieth-century psychiatry as he explored the boundaries in schizophrenia and serious mental illness in families. Joseph Schorstein (1909-76) was born in Moravia, graduated in medicine in Vienna, specialized in neurosurgery and eventually settled in Glasgow following wartime army service. Laing acknowledged the role of Schorstein as his 'spiritual mentor' and guide to the European intellectual world. This paper looks at the relationship between these two very different men and examines the career of Schorstein and the influence of his cultural background in Central Europe in shaping aspects of medical thought and culture in Glasgow.


Asunto(s)
Mentores/historia , Neurocirugia/historia , Psiquiatría/historia , Historia del Siglo XX , Humanos , Mentores/psicología , Escocia
12.
Extrem Physiol Med ; 7: 1, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29410781

RESUMEN

A career interest in thermoregulation research has included wide contrasts in the subjects of enquiry, extending from heat stroke to hypothermia, special investigations in many different purpose-built climatic chambers, laboratory-based biomedical studies together with hospital practice, and field work in tropical climates to physiological surveys on urban populations in temperate environments. The scientific process and need to focus on careful planning of experiments, using the most appropriate methods, selecting the right controls and eventually applying correct statistical analysis do not always follow a smooth transition, as illustrated in this account. The result of endeavour to resolve a human environmental problem, however, is greatly satisfying, and sometimes becomes a unique experience when the solution reveals new fundamental facts.

13.
J Chromatogr A ; 1156(1-2): 51-9, 2007 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-17084847

RESUMEN

The preparation of stationary phases with enhanced chemical stability in alkaline eluents has been the principal objective of many chromatographers. New and improved silica substrates and advanced chemical modification methods are among the possibilities being investigated to reach this objective. The present work has evaluated these two possibilities for new stationary phases. First, the silica surface was modified by reaction with zirconium tetrabutoxide to produce zirconized silica particles having about 21% (w/w) of zirconium. Then poly(methyltetradecylsiloxane) (PMTDS) was immobilized onto this surface using different doses (50-120 kGy) of gamma radiation. These new phases were characterized using elemental analysis and infrared and solid-state (29)Si-nuclear magnetic resonance (NMR) spectroscopies. These new stationary phases presented column efficiencies of about 68,000 plates m(-1), symmetric peaks for apolar compounds and retention factors that depend on the irradiation dose and show improved stability in high pH mobile phases. The separation of several pharmaceuticals at pH 11 is presented.


Asunto(s)
Cromatografía Líquida de Alta Presión/instrumentación , Dióxido de Silicio/efectos de la radiación , Siloxanos/efectos de la radiación , Acetaminofén/aislamiento & purificación , Alprazolam/aislamiento & purificación , Derivados del Benceno/aislamiento & purificación , Ibuprofeno/aislamiento & purificación , Lorazepam/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Siloxanos/síntesis química , Siloxanos/química , Espectrofotometría Infrarroja , Uracilo/aislamiento & purificación , Circonio
14.
J Chromatogr A ; 1156(1-2): 60-7, 2007 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-17462660

RESUMEN

Batches of poly(methyloctylsiloxane) (PMOS)-loaded silica were prepared by deposition from a solution of PMOS into the pores of HPLC silica. Portions of PMOS-loaded silica were subjected to a thermal treatment at 100 degrees C for 24h (condition 1) in a tube furnace under a nitrogen atmosphere. After that, the material was heated for 4h at higher temperatures (150-400 degrees C) (condition 2). Heating at higher temperatures produces polymer bilayers. Non-immobilized and thermally treated stationary phases were characterized by percent carbon, (29)Si cross-polarization magic angle spinning nuclear magnetic resonance spectroscopy and reversed-phase chromatographic performance. The results show that thermal treatment between 150 and 300 degrees C accelerates the immobilization process, possibly due to some bond breaking of the polysiloxane, with formation of strong linkages to the surface of the support, resulting in more complete coverage of the silica. The chromatographic results show an improvement of efficiency with the increase of the temperature of condition 2 up to 300 degrees C and an increase in the resolution of the components, mainly for the phase heated at 300 degrees C. Such results demonstrate that a two-step thermal treatment (100 degrees C then 150-300 degrees C) produces stationary phases with good properties for use in reversed-phase high-performance liquid chromatography.


Asunto(s)
Cromatografía Líquida de Alta Presión/instrumentación , Siloxanos/síntesis química , Calor , Dióxido de Silicio/química
15.
J Chromatogr A ; 1119(1-2): 135-9, 2006 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-16430910

RESUMEN

Reversed phases for high-performance liquid chromatography (RP-HPLC) were obtained by thermal immobilization of polysiloxanes having different length chains (C1, C8 and C14) onto HPLC silica particles. The importance both of percent loading of the stationary phase promoted by each immobilization procedure and of the length of the lateral chain of the polymer on the chromatographic performances of the phases obtained is compared and discussed.


Asunto(s)
Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Dióxido de Silicio/química , Siloxanos/química , Acenaftenos/aislamiento & purificación , Compuestos de Anilina/aislamiento & purificación , Derivados del Benceno/aislamiento & purificación , Calor , Interacciones Hidrofóbicas e Hidrofílicas , Naftalenos/aislamiento & purificación , Fenol/aislamiento & purificación , Uracilo/aislamiento & purificación
16.
J Chromatogr A ; 1122(1-2): 114-22, 2006 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-16696991

RESUMEN

The modification of silica with zirconium oxide followed by sorption and thermal immobilization of poly(methyltetradecylsiloxane) (PMTDS) is used to prepare a reversed stationary phase for high-performance liquid chromatography. The thermal immobilization of PMTDS on zirconized silica was optimized using a central composite design. The new stationary phase was characterized by spectroscopic and chromatographic methods. Stationary phases with good reproducibility and good chromatographic performance for various compounds were obtained. PMTDS thermally immobilized on zirconized silica presented quite significant chemical stability at pH 10 and 50 degrees C.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Polímeros/química , Dióxido de Silicio/química , Siloxanos/química , Circonio/química , Estructura Molecular , Polienos , Polímeros/síntesis química , Reproducibilidad de los Resultados , Siloxanos/síntesis química , Temperatura , Termogravimetría/métodos
17.
J Chromatogr A ; 1114(1): 45-52, 2006 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-16515790

RESUMEN

To extend pH stability, protective metal oxide layers, such as titanium oxide, that are more stable in alkaline medium, can be chemically bonded to the chromatographic silica surface prior to reaction with silanes. In the present work, the influence of the titanium oxide content on the chromatographic performance was investigated by synthesizing a C18 phase onto a doubly-titanized silica support and comparing its chromatographic performance with a C18 phase on singly-titanized silica. The Engelhardt and Tanaka test mixtures were used for chromatographic characterizations using short HPLC columns. The column lifetimes of these titanized phases were also compared by performing accelerated aging tests at 50 degrees C using aggressive phosphate mobile phases at pH 10.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Concentración de Iones de Hidrógeno , Titanio/química , Cromatografía Líquida de Alta Presión/instrumentación , Espectroscopía de Resonancia Magnética
18.
J Med Biogr ; 24(2): 275-80, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-24833539

RESUMEN

Levi Myers, a native of Georgetown, South Carolina, was the first Jewish medical graduate at the University of Glasgow, obtaining the MD, in 1787. Myers had been registered for studies at the University of Edinburgh for three years, from 1785/1786 to 1787/1788, after some years of training with a physician in Charleston, South Carolina. Recent studies of Jewish life in Edinburgh have revealed the evidence of a settled group of Jewish inhabitants in the city during the last quarter of the eighteenth century, during the time of Myers' sojourn in Edinburgh and thirty years before the formal inauguration of Scotland's first Jewish community. This paper examines the context of Myers' studies in Edinburgh as an American medical student and as a Jew.


Asunto(s)
Judíos/historia , Médicos/historia , Estudiantes de Medicina/historia , Historia del Siglo XVIII , Historia del Siglo XIX , Escocia , South Carolina
19.
J Chromatogr A ; 1075(1-2): 87-94, 2005 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-15974121

RESUMEN

This work describes the preparation and characterization of six stationary phases for high-performance liquid chromatography (HPLC) obtained by deposition of poly(dimethylsiloxane) (PDMS) in HPLC silica particles, followed by immobilization using different processes (thermal treatments, thermal treatment + microwave irradiation, self-immobilization + gamma irradiation and self-immobilization + microwave irradiation). The chromatographic parameters of all the phases were evaluated with a mixture of test compounds having varied natures (acid, basic and neutral). The stability of one of these phases was evaluated in both a neutral mobile phase and a higher pH mobile phase used at an elevated temperature, with promising results.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Dimetilpolisiloxanos/química , Dióxido de Silicio/química , Siliconas/química , Concentración de Iones de Hidrógeno
20.
J Chromatogr A ; 1073(1-2): 155-62, 2005 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-15909517

RESUMEN

To enhance the high pH stability of silica based reversed phases, chemically bonded octadecyl phases were prepared through silanization of titanized silica particles containing approximately 14% titanium oxide on the surface. The present work describes some spectroscopic characterizations using infrared, solid-state 13C and 29Si nuclear magnetic resonance (NMR) and X-ray absorption spectroscopy (XAS). Chromatographic characterizations for the titanized phase as well as for a conventional C18 phase, based on the same silica support without titanization, are also described using three different test mixtures containing neutral, polar and basic compounds. After an artificial stability test at pH 10, the titanized phase was again characterized by elemental and X-ray fluorescence analyses to determine the remaining carbon and titanium contents. As an application to real world samples, the separation of some herbicides and highly basic drugs using buffered mobile phases are also shown.


Asunto(s)
Cromatografía por Intercambio Iónico/instrumentación , Dióxido de Silicio/química , Titanio/química , Cromatografía por Intercambio Iónico/métodos , Concentración de Iones de Hidrógeno
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