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1.
Biol Lett ; 8(5): 821-4, 2012 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-22764111

RESUMEN

A recent increase in sea temperature has established a new ecosystem dynamic regime in the North Sea. Climate-induced changes in decapods have played an important role. Here, we reveal a coincident increase in the abundance of swimming crabs and lesser black-backed gull colonies in the North Sea, both in time and in space. Swimming crabs are an important food source for lesser black-backed gulls during the breeding season. Inhabiting the land, but feeding mainly at sea, lesser black-backed gulls provide a link between marine and terrestrial ecosystems, since the bottom-up influence of allochthonous nutrient input from seabirds to coastal soils can structure the terrestrial food web. We, therefore, suggest that climate-driven changes in trophic interactions in the marine food web may also have ensuing ramifications for the coastal ecology of the North Sea.


Asunto(s)
Braquiuros/fisiología , Charadriiformes/fisiología , Ecosistema , Animales , Clima , Cambio Climático , Decápodos , Ecología , Monitoreo del Ambiente/métodos , Cadena Alimentaria , Mar del Norte , Plancton , Dinámica Poblacional , Agua de Mar , Temperatura
2.
J Anim Physiol Anim Nutr (Berl) ; 96(5): 770-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21623931

RESUMEN

The investigation was conducted on client-owned moderately arthritic dogs with two objectives: (i) to evaluate therapeutic efficacy of type-II collagen (UC-II) alone or in combination with glucosamine hydrochloride (GLU) and chondroitin sulphate (CHO), and (ii) to determine their tolerability and safety. Dogs in four groups (n = 7-10), were treated daily for a period of 150 days with placebo (Group-I), 10 mg active UC-II (Group-II), 2000 mg GLU + 1600 mg CHO (Group-III), and UC-II + GLU + CHO (Group-IV). On a monthly basis, dogs were evaluated for observational pain (overall pain, pain upon limb manipulation, and pain after physical exertion) using different numeric scales. Pain level was also measured objectively using piezoelectric sensor-based GFP for peak vertical force and impulse area. Dogs were also examined every month for physical, hepatic (ALP, ALT and bilirubin) and renal (BUN and creatinine) functions. Based on observations, significant (p < 0.05) reduction in pain was noted in Group-II, III, and IV dogs. Using GFP, significant increases in peak vertical force (N/kg body wt) and impulse area (N s/kg body wt), indicative of a decrease in arthritis associated pain, were observed in Group-II dogs only. None of the dogs in any group showed changes in physical, hepatic or renal functions. In conclusion, based on GFP data, moderately arthritic dogs treated with UC-II (10 mg) showed a marked reduction in arthritic pain with maximum improvement by day 150. UC-II, GLU and CHO operate through different mechanisms of action, and were well tolerated over a period of 150 days.


Asunto(s)
Artritis/veterinaria , Condroitín/farmacología , Colágeno Tipo II/farmacología , Enfermedades de los Perros/tratamiento farmacológico , Glucosamina/farmacología , Dolor/veterinaria , Animales , Artritis/tratamiento farmacológico , Fenómenos Biomecánicos , Perros , Esquema de Medicación , Cojera Animal , Dolor/tratamiento farmacológico
3.
Biol Lett ; 6(6): 773-6, 2010 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-20554562

RESUMEN

A long-term time series of plankton and benthic records in the North Sea indicates an increase in decapods and a decline in their prey species that include bivalves and flatfish recruits. Here, we show that in the southern North Sea the proportion of decapods to bivalves doubled following a temperature-driven, abrupt ecosystem shift during the 1980s. Analysis of decapod larvae in the plankton reveals a greater presence and spatial extent of warm-water species where the increase in decapods is greatest. These changes paralleled the arrival of new species such as the warm-water swimming crab Polybius henslowii now found in the southern North Sea. We suggest that climate-induced changes among North Sea decapods have played an important role in the trophic amplification of a climate signal and in the development of the new North Sea dynamic regime.


Asunto(s)
Cambio Climático , Decápodos , Cadena Alimentaria , Animales , Bivalvos , Ecosistema , Peces Planos , Larva , Mar del Norte , Plancton , Dinámica Poblacional , Factores de Tiempo
4.
Nature ; 426(6967): 661-4, 2003 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-14668864

RESUMEN

The Atlantic cod (Gadus morhua L.) has been overexploited in the North Sea since the late 1960s and great concern has been expressed about the decline in cod biomass and recruitment. Here we show that, in addition to the effects of overfishing, fluctuations in plankton have resulted in long-term changes in cod recruitment in the North Sea (bottom-up control). Survival of larval cod is shown to depend on three key biological parameters of their prey: the mean size of prey, seasonal timing and abundance. We suggest a mechanism, involving the match/mismatch hypothesis, by which variability in temperature affects larval cod survival and conclude that rising temperature since the mid-1980s has modified the plankton ecosystem in a way that reduces the survival of young cod.


Asunto(s)
Ecosistema , Peces/fisiología , Plancton/fisiología , Animales , Biomasa , Dieta , Peces/crecimiento & desarrollo , Larva/fisiología , Mar del Norte , Dinámica Poblacional , Estaciones del Año , Agua de Mar , Tasa de Supervivencia , Temperatura
6.
Med Chem ; 2(1): 27-38, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16787353

RESUMEN

The lysosomal aspartyl protease, cathepsin D, has been suggested to play a role in the metastatic potential of several types of cancer. Cathepsin D is secreted by malignant cells, and is believed to be involved in the breakdown of the extracellular matrix. High levels of active cathepsin D have been found in colon cancer, prostate cancer, uterine cancer and ovarian cancer. Also cathepsin D has recently been associated with the development of Alzheimer's disease. Hydroxyethyl isosteres with cyclic tertiary amine have proven to be clinically useful as inhibitors of aspartyl proteases similar to cathepsin D in activity, such as the HIV-1 aspartyl protease. In the present study twenty-eight compounds containing (hydroxyethyl)amine isosteres with cyclic tertiary amines have been synthesized. These compounds show significant activity as cathepsin D inhibitors, many with IC(50) values in the nanomolar range. For example, the compounds that contain hydroxyethylamines where the amine is formed from N-piperazine-2-carboxylic acid methyl ester, 4y-bb, show IC(50) values ranging from 2.5 to 15 nM.


Asunto(s)
Catepsina D/antagonistas & inhibidores , Etilaminas/química , Matriz Extracelular/efectos de los fármacos , Inhibidores de Proteasas/síntesis química , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Ácido Aspártico Endopeptidasas/metabolismo , Ácidos Carboxílicos/química , Catepsina D/metabolismo , Ésteres/química , Etilaminas/farmacología , Matriz Extracelular/metabolismo , Femenino , Inhibidores de la Proteasa del VIH/síntesis química , Inhibidores de la Proteasa del VIH/farmacología , VIH-1/efectos de los fármacos , VIH-1/enzimología , Humanos , Masculino , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Piperazina , Piperazinas/química , Inhibidores de Proteasas/farmacología , Células Tumorales Cultivadas
7.
J Med Chem ; 23(5): 554-60, 1980 May.
Artículo en Inglés | MEDLINE | ID: mdl-7381856

RESUMEN

Four analogues, 10-methoxy (20), 12-aza (29), benz[j] (36), and 18-methoxy (38), of camptothecin were obtained by total synthesis. The two water-soluble analogues, 10-[(carboxymethyl)oxy]- (24) and 10-[2'-(diethylamino)-ethoxy]-20(S)-camptothecin (26), with intact ring E were prepared from natural 10 hydroxycamptothecin (3). In general, there was a good correlation between in vitro 9KB cytotoxicity and activity in the P-388 leukemia system. While the aza analogue 29 was active in P-388 only at a much higher dose level than natural camptothecin (1), the 18-methoxy analogue 38 exhibited activity comparable to that of 1. The water-soluble derivative 24 was inactive. The amine hydrochloride 26 showed excellent activity at a high dose level. This could be due to its hydrolysis to 3. dl-Camptothecin (17) was roughly half as active as 1, indicating that the l isomer is inactive.


Asunto(s)
Camptotecina/análogos & derivados , Animales , Camptotecina/síntesis química , Camptotecina/farmacología , Células Cultivadas , Fenómenos Químicos , Química , Leucemia P388/tratamiento farmacológico , Ratones
8.
Arch Ophthalmol ; 118(7): 924-8, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10900105

RESUMEN

BACKGROUND: Clinically abnormal retinal vessels unique to cerebral malaria have previously been shown to be associated with a poor outcome in African children. There have been no studies of the histopathological correlates of these vessels. DESIGN: This is a descriptive study of the clinical-histopathological correlates of the retinal vessels of 11 children who died with cerebral malaria. RESULTS: The retinal vessels in children with cerebral malaria contained many parasitized red blood cells; these cells tended to cluster at the periphery of vessels or, in the case of capillaries, to fill the vessel. Those with late-stage parasites had markedly reduced amounts of hemoglobin. The pattern of dehemoglobinization corresponds to the pattern of clinically abnormal vessels. CONCLUSIONS: The sequestration of late-stage parasitized red blood cells with reduced amounts of hemoglobin accounts for the unique white and pale orange retinal vessels seen in cerebral malaria. Clinical examination of these "marked" vessels offers a method to monitor a basic pathophysiological process of cerebral malaria in vivo. Arch Ophthalmol. 2000;118:924-928


Asunto(s)
Infecciones Parasitarias del Ojo/patología , Malaria Cerebral/patología , Enfermedades de la Retina/patología , Vasos Retinianos/patología , Animales , Niño , Preescolar , Eritrocitos/parasitología , Infecciones Parasitarias del Ojo/parasitología , Humanos , Malaria Cerebral/parasitología , Plasmodium falciparum/aislamiento & purificación , Enfermedades de la Retina/parasitología , Vasos Retinianos/parasitología
9.
Am J Ophthalmol ; 125(3): 312-24, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9512148

RESUMEN

PURPOSE: To describe the clinical features of a disorder characterized by chronic multifocal retinal infiltrates and uveitis in individuals with human immunodeficiency virus (HIV) disease. METHODS: We reviewed the medical records of HIV-infected patients with multifocal retinal infiltrates of unknown cause seen by investigators at four institutions. The following data were collected: demographic characteristics, presenting signs and symptoms, laboratory test results, and course of disease. RESULTS: We identified 26 HIV-infected patients (50 involved eyes) with this syndrome. Median CD4+ T-lymphocyte count at presentation was 272 per microl (range, 7 to 2,118 per microl). The most common presenting symptom was floaters. Median visual acuity of involved eyes at presentation was 20/20 (range, 20/15 to 20/100) and remained stable (median, 20/20; range, 20/15 to 20/70) after a median follow-up period of 9 months (range, 0 to 110 months). Typical retinal lesions were gray-white or yellow, irregular in shape, and less than 200 microm in greatest dimension. All were located in the midperiphery or anterior retina and enlarged slowly or remained static in size. Mild to moderate anterior chamber or vitreous humor inflammatory cells were present in 47 of 50 eyes (26 of 26 patients). Retinal lesions possibly responded to zidovudine but not to acyclovir or ganciclovir. Anterior chamber and vitreous humor inflammatory reactions responded to topical or periocular injections of corticosteroid. CONCLUSIONS: Uveitis with chronic multifocal retinal infiltrates is a distinct clinical entity of unknown cause that occurs in HIV-infected patients. Retinal lesions may respond to antiretroviral therapy. Visual prognosis is good.


Asunto(s)
Infecciones por VIH/complicaciones , Enfermedades de la Retina/complicaciones , Uveítis/complicaciones , Aciclovir/uso terapéutico , Adulto , Fármacos Anti-VIH/uso terapéutico , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/inmunología , Enfermedad Crónica , Fondo de Ojo , Ganciclovir/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Retina/tratamiento farmacológico , Enfermedades de la Retina/patología , Síndrome , Uveítis/tratamiento farmacológico , Uveítis/patología , Agudeza Visual , Zidovudina/uso terapéutico
10.
Br J Ophthalmol ; 83(7): 792-5, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10381665

RESUMEN

AIM: To develop and test a practical visual function assessment for use in developing countries. METHODS: Using focus group discussions and interviews with eyecare workers and low vision specialists in Malawi, 13 questions related to visual characteristics of activities of daily living were designed. Patients presenting to an eye clinic were recruited and interviewed. Visual acuity, near vision, and contrast sensitivity were measured. Analysis sought to determine the degree of correlation between the vision indices and visual function. RESULTS: The visual function questionnaire was easy to administer. Visual function correlated with visual acuity, contrast sensitivity, near vision, and patient reported visual problem. People with a higher frequency of "not applicable" responses had lower visual function scores. Multivariate modelling revealed that visual acuity and number of questions felt to be applicable were independently associated with visual function. Reducing the questionnaire to nine questions did not affect the degree of correlation with any of the visual indices. CONCLUSION: The authors' visual function assessment correlates well with different measures of visual acuity. People with reduced vision for a prolonged period may no longer consider doing certain tasks and the number of questions considered appropriate by an individual may be an additional measure of visual function. Assessment of visual function by health workers may be a valuable tool in improving surgical uptake by encouraging both health personnel and patients to recognise that they have difficulties undertaking activities of daily living as well as a measure of monitoring and evaluating cataract outcomes.


Asunto(s)
Trastornos de la Visión/diagnóstico , Selección Visual/métodos , Sensibilidad de Contraste/fisiología , Femenino , Humanos , Malaui , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Trastornos de la Visión/fisiopatología , Agudeza Visual/fisiología
11.
Arch Pathol Lab Med ; 100(12): 628-9, 1976 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1036673

RESUMEN

Acute renal failure was observed postoperatively in a patient after halothane anesthesia. The clinical and pathologic findings in this case were remarkably similar to those found in patients with renal failure after methoxyflurane anesthesia.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Halotano/efectos adversos , Lesión Renal Aguda/patología , Anciano , Femenino , Humanos , Riñón/patología
17.
Am Econ ; 16: 64-5, 1972.
Artículo en Inglés | MEDLINE | ID: mdl-12333101

RESUMEN

PIP: Rumania provides the opportunity to determine the effects of change in abortion laws by comparing it to Bulgaria, Czechoslovakia, and Hungary with whom it has a similar background, government, and growth pattern. Rumania had legalized abortion in 1957 but reversed its decision in 1966. 3 years later when compared with the other countries where legalized abortion continued, there was a significant increase in the crude birthrate of Rumania, a notable increase resulting mainly from the change in its abortion law. This same conclusion can also be reached by applying microeconomic theory using the concept that children are, on the margin, the result of a maximizing process. The decision to have an abortion in the countries in question is voluntary. No one is coerced and even when abortion is illegal it can be seen as an increase in price. By doing this the decision of whether to have an abortion can be analyzed as a microeconomic decision. The birth decision is made on the margin where the expected cost of a child is compared with the expected return. Traditional analysis implies that there is no cost involved in not having children, but there are both monetary and nonmonetary costs, the latter being physical and psychological. All forms of birth control involve costs, and the following analysis could be used on any of them. By combining the cost of preventing birth with the concept of traditional theory, there is now a threefold margin of decision rather than a twofold one. The cost of prevention must be included. If the amount that will have to be expended for prevention exceeds the net cost of having the child, the ultimate decision will be to have the child. The demand curve for abortion shows that as abortion is legalized the supply curve will shift out and the price will fall, with the opposite case if abortion is again made illegal. The demand curve might also shift as abortion was legalized or made illegal as the desire for abortion could change. It could be altered by such concepts as obeying the law and social acceptance. With abortion legal and the cost of prevention lower, fewer people will decide to have children. This microanalysis explains well why the crude birthrate rose so abrubtly in Rumania.^ieng


Asunto(s)
Aborto Inducido , Tasa de Natalidad , Regulación de la Población , Demografía , Países Desarrollados , Europa (Continente) , Europa Oriental , Servicios de Planificación Familiar , Fertilidad , Planificación en Salud , Población , Dinámica Poblacional , Evaluación de Programas y Proyectos de Salud , Rumanía
18.
Proc Soc Exp Biol Med ; 180(1): 121-5, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3849803

RESUMEN

Tissue kallikrein content and rate of synthesis have been measured in the kidney and submaxillary gland of the rat after a single physiological dose of aldosterone, and during the time in which the physiological effects of aldosterone are evident. No change in the renal cortical tissue content of immunoreactive kallikrein, in either adrenalectomized or sham-operated animals, was seen within 3 hr of the administration of aldosterone. The kininogenase activity of these samples also did not change. The rates of kallikrein synthesis in the submaxillary gland and the whole kidney were measured by specific immunoprecipitation of kallikrein after 20 min of [35S]methionine incorporation, and again no aldosterone effect was seen. We conclude that, under the conditions of these experiments, aldosterone does not induce the synthesis of tissue kallikrein in either the submaxillary gland or the kidney.


Asunto(s)
Aldosterona/farmacología , Calicreínas/metabolismo , Riñón/enzimología , Glándula Submandibular/enzimología , Adrenalectomía , Animales , Calicreínas/biosíntesis , Cinética , Masculino , Metionina/metabolismo , Ratas , Ratas Endogámicas
19.
Science ; 296(5573): 1692-4, 2002 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-12040196

RESUMEN

We provide evidence of large-scale changes in the biogeography of calanoid copepod crustaceans in the eastern North Atlantic Ocean and European shelf seas. We demonstrate that strong biogeographical shifts in all copepod assemblages have occurred with a northward extension of more than 10 degrees latitude of warm-water species associated with a decrease in the number of colder-water species. These biogeographical shifts are in agreement with recent changes in the spatial distribution and phenology detected for many taxonomic groups in terrestrial European ecosystems and are related to both the increasing trend in Northern Hemisphere temperature and the North Atlantic Oscillation.


Asunto(s)
Clima , Crustáceos , Ecosistema , Agua de Mar , Zooplancton , Animales , Océano Atlántico , Geografía , Análisis de Componente Principal , Estaciones del Año , Temperatura
20.
Ann Surg ; 182(2): 161-2, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1211994

RESUMEN

Renal failure is often the presenting problem with amyloidosis and it portends a generally poor prognosis. Two of 121 patients in a home dialysis program were found to have amyloidosis after they developed unusual complications, ischemic colitis and femoral neuropathy. Both ultimately died as a result of their disease. From the limited experience that is reported, it appears that renal transplantation offers a better alternative for long term therapy than hemodialysis.


Asunto(s)
Amiloidosis/complicaciones , Colitis/etiología , Fallo Renal Crónico/etiología , Parálisis/etiología , Muslo , Adulto , Colon/irrigación sanguínea , Femenino , Humanos , Isquemia/etiología , Masculino , Persona de Mediana Edad , Enfermedades Musculares/etiología , Diálisis Renal
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