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1.
Philos Trans R Soc Lond B Biol Sci ; 378(1878): 20220103, 2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-37066648

RESUMEN

The open ocean offers a suite of ecological conditions promoting the occurrence of multi-species predator aggregations. These mixed predator aggregations typically hunt large groups of relatively small and highly cohesive prey. However, the mechanisms and functions of these mixed predator aggregations are largely unknown. Even basic knowledge of whether the predator species' interactions are mutualistic, commensal or parasitic is typically missing. Moreover, recordings of attack and capture rates of marine multi-species predator aggregations, which are critical in understanding how and why these interactions have evolved, are almost completely non-existent owing to logistical challenges. Using underwater video, we quantified the attack and capture rates of two high-trophic level marine predators, California sea lions (Zalophus californianus) and striped marlin (Kajikia audax) attacking schools of fishes in the Southern California Current System, offshore the Baja California Peninsula. Recording over 5000 individual attacks across 13 fish schools, which varied in species, size and predator composition, we found that sea lions kleptoparasitized striped marlin hunts and reduced the frequency of marlin attacks and captures via interference competition. We discuss our results in the context of the phenotypic differences between the predator species and implications for a better understanding of multi-species predator aggregations. This article is part of the theme issue 'Mixed-species groups and aggregations: shaping ecological and behavioural patterns and processes'.


Asunto(s)
Perciformes , Conducta Predatoria , Leones Marinos , Animales , Peces , México
2.
Z Rheumatol ; 71(10): 841-9, 2012 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-22932980

RESUMEN

Rheumatoid arthritis (RA) represents an autoimmune disease affecting mostly joints, in particular small finger and toe joints. In addition RA can show extra-articular manifestations in many organs. Information on the frequency of extra-articular manifestations (EAMs) in RA varies greatly in different publications from 17.8% to 40.9% and EAMs tend to become higher with increasing duration and severity of the disease. The exact etiology and pathogenesis are still unclear but vasculitic alterations together with deposition of immune complexes can often be found histopathologically in affected organs. It must also be taken into consideration that EAMs can also be a result of the pharmaceutical therapy. The organ findings can vary greatly which is also reflected in the multitude of clinical symptoms. Possible target organs are the blood vessels, kidneys, central nervous system, cardiovascular system, the lungs, eyes, skin, nails as well as blood and the hemopoetic system. The prognosis for RA becomes progressively worse in the presence of EAMs. Regular and continuous control investigations are necessary in order to be able to diagnose EAMs early and to begin therapy. Therapy includes the administration of non-steroidal anti-inflammatory drugs (NSAIDs) and disease-modifying antirheumatic drugs (DMARDs) and especially in advanced stages cyclophosphamide or biologicals. Therapy is still very empirical due to the lack of appropriate studies.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/epidemiología , Encefalopatías/epidemiología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Hematológicas/epidemiología , Enfermedades Renales/epidemiología , Enfermedades de la Piel/epidemiología , Productos Biológicos/uso terapéutico , Encefalopatías/tratamiento farmacológico , Enfermedades Cardiovasculares/tratamiento farmacológico , Comorbilidad , Enfermedades Hematológicas/tratamiento farmacológico , Humanos , Incidencia , Enfermedades Renales/tratamiento farmacológico , Pronóstico , Factores de Riesgo , Enfermedades de la Piel/tratamiento farmacológico
3.
Z Rheumatol ; 71(6): 515-7, 2012 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-22802026

RESUMEN

Primary manifestation of an autoinflammatory systemic disease was found in a 15-year-old patient, which initially ran a fulminant course. The course was first controlled by therapy with steroids and cyclosporin A. In the course of the disease, the patient developed a therapy refractory polyarthritis, which failed to respond to a combination of disease-modifying antirheumatic drugs (DMARDs) and tumor necrosis factor (TNF) inhibitors. A good disease control could only be achieved with an interleukin 6 (IL-6) blockade and DMARDs.


Asunto(s)
Artritis/diagnóstico , Artritis/terapia , Ciclosporina/uso terapéutico , Fiebre/diagnóstico , Fiebre/terapia , Esteroides/uso terapéutico , Adolescente , Antiasmáticos/uso terapéutico , Antiinflamatorios/uso terapéutico , Artritis/complicaciones , Fiebre/complicaciones , Humanos , Masculino , Insuficiencia del Tratamiento , Resultado del Tratamiento
4.
J Hered ; 94(2): 133-47, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12721225

RESUMEN

The population structure of Anopheles gambiae in Africa was studied using 11 microsatellite loci in 16 samples from 10 countries. All loci are located outside polymorphic inversions. Heterogeneity among loci was detected and two putative outlier loci were removed from analyses aimed at capturing genome-wide patterns. Two main divisions of the gene pool were separated by high differentiation (F(ST) > 0.1). The northwestern (NW) division included populations from Senegal, Ghana, Nigeria, Cameroon, Gabon, Democratic Republic of Congo (DRC), and western Kenya. The southeastern (SE) division included populations from eastern Kenya, Tanzania, Malawi, and Zambia. Inhospitable environments for A. gambiae along the Rift Valley partly separate these divisions. Reduced genetic diversity in the SE division and results of an analysis based on private alleles support the hypothesis that a recent bottleneck, followed by colonization from the NW populations shaped this structure. In the NW division, populations possessing the M rDNA genotype appeared to form a monophyletic clade. Although genetic distance increased with geographic distance, discontinuities were suggested between certain sets of populations. The absence of heterozygotes between sympatric M and S populations in the DRC and the high differentiation in locus 678 (F(ST)>0.28) contrasted with low differentiation in all other loci (-0.02

Asunto(s)
Anopheles/genética , Genética de Población , África del Sur del Sahara , Animales , Variación Genética , Homocigoto , Repeticiones de Microsatélite , Filogenia
5.
Mol Biol Evol ; 18(7): 1353-64, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11420373

RESUMEN

Gene flow in malaria vectors is usually estimated based on differentiation indices (e.g., F(ST)) in order to predict the contemporary spread of genes such as those conferring resistance to insecticides. This approach is reliant on a number of assumptions, the most crucial, and the one most likely to be violated in these species, being mutation-migration-drift equilibrium. Tests of this assumption for the African malaria vectors Anopheles gambiae and Anopheles arabiensis are the focus of this study. We analyzed variation at 18 microsatellite loci and the ND5 region of the mitochondrial genome in two populations of each species. Equilibrium was rejected by six of eight tests for the A. gambiae population from western Kenya and by three tests in eastern Kenya. In western Kenya, all departures from equilibrium were consistent with a recent population expansion, but in eastern Kenya, there were traces of a recent expansion and a bottleneck. Equilibrium was also rejected by two of the eight tests for both A. arabiensis populations; the departure from equilibrium was consistent with an expansion. These multiple-locus tests detected a genomewide effect and therefore a demographic event rather than a locus-specific effect, as would be caused by selection. Disequilibrium due to a recent expansion in these species implies that rates of gene flow, as inferred from differentiation indices, are overestimates as they include a historical component. We argue that the same effect applies to the majority of pest species due to the correlation of their demography with that of humans.


Asunto(s)
Anopheles/genética , Insectos Vectores/genética , África , Animales , ADN Mitocondrial/genética , Evolución Molecular , Genética de Población , Humanos , Malaria/transmisión , Repeticiones de Microsatélite , Modelos Genéticos , Mutación , Polimorfismo Genético , Especificidad de la Especie
9.
Nephrol News Issues ; 15(5): 42, 46-8, 50, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12108962

RESUMEN

This article describes one renal disease management organization's experience in implementing a pre-dialysis care management program to improve outcomes in patients who develop end-stage renal disease (ESRD). Optimal Renal Care, a national renal disease management company, has implemented care management programs for 600+ ESRD patients and 600+ pre-ESRD patients in Oregon (1998) and Hawaii (1999). This article describes our Oregon pre-ESRD program's start-up experience.


Asunto(s)
Manejo de la Enfermedad , Fallo Renal Crónico/terapia , Planificación de Atención al Paciente , Diálisis Renal , Humanos , Defensa del Paciente , Grupo de Atención al Paciente , Educación del Paciente como Asunto , Selección de Paciente , Desarrollo de Programa , Resultado del Tratamiento
10.
Fertil Steril ; 72(4): 666-9, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10521107

RESUMEN

OBJECTIVE: To study the effect of in vitro culture on the quality of human testicular sperm and the efficiency of intracytoplasmic sperm injection with in vitro cultured testicular sperm. DESIGN: Clinical study. SETTING: A private IVF center. PATIENT(S): Twenty consecutively seen IVF patients undergoing testicular biopsies for ICSI. INTERVENTION(S): The testicular specimens were cultured in vitro for 24 hours and the isolated spermatozoa were microinjected. MAIN OUTCOME MEASURE(S): Preincubation and postculture sperm motility, and fertilization, implantation, and pregnancy rates after intracytoplasmic sperm injection. RESULT(S): Motility increased from initial nonmotile or twitching sperm to free motile sperm in 18 of 20 cases. The injection of in vitro cultured testicular sperm resulted in a fertilization rate of 58%, an implantation rate of 20%, and a pregnancy rate of 45%. CONCLUSION(S): A testicular biopsy procedure can be performed the day before egg retrieval. Despite the low initial sperm quality, a high percentage of the prepared testicular sperm showed increased motility after 24 hours of culture. The injection of in vitro cultured testicular sperm into matured oocytes resulted in fertilization, implantation, and pregnancy rates comparable to those obtained with ejaculated sperm.


Asunto(s)
Oocitos , Inyecciones de Esperma Intracitoplasmáticas , Espermatozoides , Recolección de Tejidos y Órganos , Adulto , Células Cultivadas , Implantación del Embrión , Femenino , Fertilización , Humanos , Masculino , Embarazo , Índice de Embarazo , Motilidad Espermática , Espermatozoides/fisiología , Testículo , Factores de Tiempo
11.
Clin Nucl Med ; 24(10): 781-3, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10512105

RESUMEN

PURPOSE: To assess the use of a Tc-99m erythrocyte-labeled SPECT scan to characterize a giant splenic hemangioma. METHODS: A patient clinically mistaken to have a myelodysplastic disorder underwent a contrast-enhanced CT followed by a Tc-99m erythrocyte-labeled SPECT scan. RESULTS: CT showed a heterogeneous vascular lesion arising in the spleen. Percutaneous biopsy was nondiagnostic. A Tc-99m erythrocyte-labeled SPECT study revealed findings consistent with a giant splenic hemangioma, which was subsequently confirmed at surgery. CONCLUSION: A Tc-99m erythrocyte-labeled SPECT scan may be very useful in confirming the diagnosis of a large or giant splenic hemangioma.

13.
Compr Ther ; 25(2): 90-4, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10091013

RESUMEN

Erectile dysfunction is a common problem affecting men. Sildenafil (Viagra) is the first oral medication approved for the treatment of erectile dysfunction. It has proven to be an effective option in the treatment of erectile dysfunction of different etiologies.


Asunto(s)
Disfunción Eréctil/tratamiento farmacológico , Inhibidores de Fosfodiesterasa/uso terapéutico , Piperazinas/uso terapéutico , Ensayos Clínicos como Asunto , Contraindicaciones , Sinergismo Farmacológico , Disfunción Eréctil/fisiopatología , Humanos , Hipotensión/inducido químicamente , Masculino , Nitratos/efectos adversos , Erección Peniana/efectos de los fármacos , Erección Peniana/fisiología , Inhibidores de Fosfodiesterasa/farmacología , Piperazinas/farmacología , Purinas , Citrato de Sildenafil , Sulfonas
14.
Cleve Clin J Med ; 65(6): 301-4, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9637957

RESUMEN

Sildenafil, the first oral drug for treating male erectile dysfunction, appears effective and well tolerated. However, more time and experience will be needed to establish this drug's true efficacy and safety.


Asunto(s)
Inhibidores Enzimáticos/uso terapéutico , Disfunción Eréctil/tratamiento farmacológico , Piperazinas/uso terapéutico , Inhibidores Enzimáticos/farmacología , Humanos , Masculino , Pene/efectos de los fármacos , Piperazinas/farmacología , Purinas , Citrato de Sildenafil , Sulfonas , Resultado del Tratamiento
15.
Proc Natl Acad Sci U S A ; 95(8): 4425-30, 1998 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-9539753

RESUMEN

We have analyzed DNA sequences from world-wide geographic strains of Plasmodium falciparum and found a complete absence of synonymous DNA polymorphism at 10 gene loci. We hypothesize that all extant world populations of the parasite have recently derived (within several thousand years) from a single ancestral strain. The upper limit of the 95% confidence interval for the time when this most recent common ancestor lived is between 24,500 and 57,500 years ago (depending on different estimates of the nucleotide substitution rate); the actual time is likely to be much more recent. The recent origin of the P. falciparum populations could have resulted from either a demographic sweep (P. falciparum has only recently spread throughout the world from a small geographically confined population) or a selective sweep (one strain favored by natural selection has recently replaced all others). The selective sweep hypothesis requires that populations of P. falciparum be effectively clonal, despite the obligate sexual stage of the parasite life cycle. A demographic sweep that started several thousand years ago is consistent with worldwide climatic changes ensuing the last glaciation, increased anthropophilia of the mosquito vectors, and the spread of agriculture. P. falciparum may have rapidly spread from its African tropical origins to the tropical and subtropical regions of the world only within the last 6,000 years. The recent origin of the world-wide P. falciparum populations may account for its virulence, as the most malignant of human malarial parasites.


Asunto(s)
Genes Protozoarios , Malaria Falciparum/parasitología , Filogenia , Plasmodium falciparum/genética , Plasmodium/genética , Polimorfismo Genético , África , Animales , Asia , Clima , ADN Protozoario/química , ADN Protozoario/genética , Demografía , Evolución Molecular , Humanos , Estadios del Ciclo de Vida , Malaria/parasitología , Países Bajos , Plasmodium/clasificación , Plasmodium falciparum/clasificación , Plasmodium falciparum/fisiología , América del Sur , Tetrahidrofolato Deshidrogenasa/genética , Tiempo
16.
J Urol ; 158(2): 460-3, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9224323

RESUMEN

PURPOSE: We describe a surgical modification of the Nesbit procedure to correct Peyronie's disease, and compare the results of this procedure with those of 2 other surgical techniques. MATERIALS AND METHODS: In 30 patients a vertical incision in the tunica albuginea was closed in a horizontal fashion with permanent suture knots buried beneath the tunica in a running looped fashion, resulting in watertight closure with no exposed suture material. A standard Nesbit procedure and plaque excision with a polyethylene terephthalate mesh reinforced silicone sheet patch graft were done in 28 cases each. RESULTS: Elimination of penile curvature, patient satisfaction and postoperative impotence rates were not statistically different for standard and modified Nesbit procedures. However, plaque excision and synthetic patch grafting resulted in less elimination of curvature (61%, p = 0.004), a lower rate of satisfaction (30%, p = 0.00002) and a higher incidence of impotence after surgery (18%, p = 0.04). The modified Nesbit procedure achieved an overall higher rate of correction of curvature than the standard approach (93 versus 79%). CONCLUSIONS: A modified Nesbit procedure achieves the greatest functional success for Peyronie's disease with an acceptably low complication rate.


Asunto(s)
Induración Peniana/cirugía , Adolescente , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Procedimientos Quirúrgicos Operativos/métodos , Resultado del Tratamiento
17.
J Urol ; 154(5): 1740-3, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7563336

RESUMEN

PURPOSE: We evaluated the relative use of RigiScan measurement of radial rigidity compared to sleep laboratory measurement of axial rigidity and trained observer determination of erectile function in the diagnosis of organic impotence. MATERIALS AND METHODS: A total of 28 patients underwent simultaneous 2-night formal sleep laboratory nocturnal penile tumescence and RigiScan monitoring. Standard normal values for radial rigidity and axial rigidity were tested for accuracy in predicting normal nocturnal penile tumescence compared to trained observer determination of the adequacy of an erection for penetration. RESULTS: RigiScan tip measurements correlated poorly with buckling pressure, while base measurements strongly correlated (p = 0.0005). Observer determination of a functional erection was strongly associated with tip (p = 0.002), base (p = 0.0005) and buckling pressure measurements (p = 0.0005). Using observer determination as the gold standard receiver operating curves were generated to select RigiScan base and buckling pressure measurements that predicted functional erections with the highest sensitivity and specificity. CONCLUSIONS: RigiScan is a useful tool for measuring nocturnal penile tumescence. However, base measurements are more accurate than tip measurements for evaluating erectile function. The currently accepted level of rigidity used to define a normal erection (70% or greater) overestimates organic erectile dysfunction.


Asunto(s)
Disfunción Eréctil/diagnóstico , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Erección Peniana , Estudios Prospectivos , Sensibilidad y Especificidad , Sueño
18.
Semin Urol Oncol ; 13(4): 262-6, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8595549

RESUMEN

Renal adenoma and oncocytoma are relatively common, benign solid renal tumors. These lesions rarely present with specific genitourinary symptoms and are most often incidentally detected as small renal masses. While some radiologic findings are suggestive of either lesion, there are no pathognomonic radiologic features that can dependably differentiate them from renal cell carcinoma. Renal adenoma is often histologically indistinguishable from renal cell carcinoma, and renal oncocytoma shares many cellular features with granular renal cell carcinoma, thereby limiting the utility of needle biopsy or aspiration cytology for diagnosis. These tumors are also often found associated with renal cell carcinoma in the same or contralateral kidney, so that surgical excision is the only reliable means to achieve both definitive diagnosis and treatment.


Asunto(s)
Adenoma Oxifílico/diagnóstico , Adenoma/diagnóstico , Neoplasias Renales/diagnóstico , Adenoma/epidemiología , Adenoma/patología , Adenoma/cirugía , Adenoma Oxifílico/epidemiología , Adenoma Oxifílico/patología , Carcinoma de Células Renales/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Nefrectomía , Pronóstico , Tomografía Computarizada por Rayos X
19.
Urology ; 46(4): 577-80, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7571235

RESUMEN

Erectile dysfunction can result from blunt or penetrating pelvic or perineal trauma. Rupture of the corpora cavernosa leading to loss of the veno-occlusive mechanism and penile artery occlusion have been found in these patients. We present a case of immediate loss of erectile function after penetrating perineal trauma resulting in corpus cavernosum rupture and traumatic occlusion of multiple arteries in the hypogastric-cavernous bed. Conservative management of the corpus injury resulted in post-traumatic aneurysmal dilation at the site of injury with venous leakage from aberrant veins. Penile arterial revascularization and aneurysm repair with deep penile venous ligation resulted in near-complete return of normal erectile function.


Asunto(s)
Aneurisma/cirugía , Disfunción Eréctil/cirugía , Pene/irrigación sanguínea , Pene/lesiones , Perineo/lesiones , Heridas Penetrantes/complicaciones , Adolescente , Aneurisma/etiología , Arterias/cirugía , Disfunción Eréctil/etiología , Humanos , Ligadura , Masculino , Pene/cirugía , Inducción de Remisión , Venas
20.
J Urol ; 154(2 Pt 1): 387-90, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7609104

RESUMEN

PURPOSE: We determine the colony counts of organisms present on culture of clinically uninfected genitourinary prostheses at reoperation for reasons other than infection. These results served as control data for comparison with cultures from infected devices to determine the relative incidence of organisms involved. MATERIALS AND METHODS: Cultures were prospectively obtained from 65 penile prostheses and 22 artificial urinary sphincters. Patients were followed for a minimum of 12 months after reoperation or until development of infection (mean 27 months) at which time cultures were again obtained. RESULTS: Low colony counts of Staphylococcus epidermidis were isolated from 40% of uninfected penile prostheses and 36% of artificial urinary sphincters. Only 3 of these devices later became infected (9%) and in all cases a higher colony count of another organism was found at explanation. CONCLUSIONS: While Staph. epidermidis can cause prosthesis infection, low colony counts of the organism may not be associated with clinical infection. Therefore, the high incidence of infection attributed to this organism may be overestimated.


Asunto(s)
Prótesis de Pene/efectos adversos , Prótesis de Pene/microbiología , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/aislamiento & purificación , Esfínter Urinario Artificial/efectos adversos , Estudios de Casos y Controles , Recuento de Colonia Microbiana , Estudios de Seguimiento , Humanos , Periodo Intraoperatorio , Masculino , Estudios Prospectivos , Reoperación
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