RESUMEN
Atypical hemolytic uremic syndrome is a rare disease associated with genetic or acquired defects in complement regulation which frequently leads to renal failure. Disease often recurs early after kidney transplantation, leading to a rapid irreversible loss of function. Extrarenal features, such as hemolysis and thrombocytopenia, may not always occur, and diagnosis is made by demonstrating the classic features of thrombotic microangiopathy on renal biopsy. Eculizumab, a terminal complement inhibitor, has been used successfully to treat fulminant early recurrent disease after transplantation. We describe a case of disease recurrence presenting in the second year after transplantation with a gradual decline in function and the first report of eculizumab treatment for chronic thrombotic microangiopathy in a transplanted kidney. The resultant diagnostic challenges and successful response to eculizumab in this setting are discussed.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Trasplante de Riñón , Disfunción Primaria del Injerto/etiología , Microangiopatías Trombóticas/tratamiento farmacológico , Enfermedad Crónica , Femenino , Humanos , Riñón/patología , Persona de Mediana Edad , Disfunción Primaria del Injerto/diagnóstico , Disfunción Primaria del Injerto/tratamiento farmacológico , Recurrencia , Microangiopatías Trombóticas/etiologíaRESUMEN
Outcomes after islet transplantation continue to improve but etiology of graft failure remains unclear. De novo donor-specific human leukocyte antigen (HLA) antibodies (DSA) posttransplant are increasingly recognized as a negative prognostic marker. Specific temporal associations between DSA and graft function remain undefined particularly in programs undertaking multiple sequential transplants. Impact of de novo DSA on graft function over 12 months following first islet transplant was determined prospectively in consecutive recipients taking tacrolimus/mycophenolate immunosuppression at a single center. Mixed-meal tolerance test was undertaken in parallel with HLA antibody assessment pretransplant and 1-3 months posttransplant. Sixteen participants received a total of 26 islet transplants. Five (19%) grafts were associated with de novo DSA. Five (31%) recipients were affected: three post-first transplant; two post-second transplant. DSA developed within 4 weeks of all sensitizing grafts and were associated with decreased stimulated C-peptide (median [interquartile range]) at 3 months posttransplant (DSA negative: 613(300-1090); DSA positive 106(34-235) pmol/L [p = 0.004]). De novo DSA directed against most recent islet transplant were absolutely associated with loss of graft function despite maintained immunosuppression at 12 months in the absence of a rescue nonsensitizing transplant. Alemtuzumab induction immunosuppression was associated with reduced incidence of de novo DSA formation (p = 0.03).
Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Rechazo de Injerto/epidemiología , Antígenos HLA/inmunología , Trasplante de Islotes Pancreáticos/efectos adversos , Isoanticuerpos/sangre , Donantes de Tejidos , Adulto , Femenino , Estudios de Seguimiento , Rechazo de Injerto/etiología , Supervivencia de Injerto , Prueba de Histocompatibilidad , Humanos , Incidencia , Isoanticuerpos/inmunología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Pronóstico , Estudios Prospectivos , Factores de RiesgoRESUMEN
The executive summary provides an overview of some of V&C's key recommendations regarding next steps in the effort to mobilize the biology community. It is, in essence, a call for national service. A publication discussing these recommendations and action items in more depth will be available later this year. Meanwhile, we highly recommend reading the Executive Summary of V&C, the NAS report (NAS, 2010), and a seminal article by Labov et al. (2010) summarizing the synergy created by these several reports on the changing nature of studies in biology and concomitant need to change biology education. Then, take action! Our hope is to see the formation of a community of biologists, similar to that forming in geology (Manduca et al., 2010): one that will advance biology undergraduate education so it truly reflects the discipline it serves.
Asunto(s)
Biología/educación , Universidades , Academias e Institutos , Simulación por Computador , Docentes , Internet , Aprendizaje Basado en Problemas , Estudiantes , EnseñanzaRESUMEN
The Human Leukocyte Antigen (HLA) system plays a critical role in regulating the immune response. As a consequence of its role in immune regulation and exquisite polymorphism, the HLA system also constitutes an immunological barrier which must be avoided or otherwise overcome in clinical transplantation. This introductory review provides a brief summary of the immunobiology of the HLA system and methodology for HLA typing, antibody screening and patient-donor cross-matching. This constitutes a basis for consideration of the importance of these procedures in the system-specific reviews which follow.
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Antígenos HLA/inmunología , Prueba de Histocompatibilidad/métodos , Histocompatibilidad/inmunología , Humanos , Isoanticuerpos/análisis , Inmunología del TrasplanteRESUMEN
Since its use as a model to study metazoan parasite culture and in vitro development, the plerocercoid of the tapeworm, Ligula intestinalis, has served as a useful scientific tool to study a range of biological factors, particularly within its fish intermediate host. From the extensive long-term ecological studies on the interactions between the parasite and cyprinid hosts, to the recent advances made using molecular technology on parasite diversity and speciation, studies on the parasite have, over the last 60 years, led to significant advances in knowledge on host-parasite interactions. The parasite has served as a useful model to study pollution, immunology and parasite ecology and genetics, as well has being the archetypal endocrine disruptor.
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Cestodos/fisiología , Infecciones por Cestodos/veterinaria , Cyprinidae/parasitología , Animales , Modelos Animales de Enfermedad , Interacciones Huésped-Parásitos , ReproducciónRESUMEN
Coral throughout the world are under threat. To save coral via cryopreservation methods, the Symbiodinium algae that live within many coral cells must also be considered. Coral juvenile must often take up these important cells from their surrounding water and when adult coral bleach, they lose their endosymbiotic algae and will die if they are not regained. The focus of this paper was to understand some of the cryo-physiology of the endosymbiotic algae, Symbiodinium, living within three species of Hawaiian coral, Fungia scutaria, Porites compressa and Pocillopora damicornis in Kaneohe Bay, Hawaii. Although cryopreservation of algae is common, the successful cryopreservation of these important coral endosymbionts is not common, and these species are often maintained in live serial cultures within stock centers worldwide. Freshly-extracted Symbiodinium were exposed to cryobiologically appropriate physiological stresses and their viability assessed with a Pulse Amplitude Fluorometer. Stresses included sensitivity to chilling temperatures, osmotic stress, and toxic effects of various concentrations and types of cryoprotectants (i.e., dimethyl sulfoxide, propylene glycol, glycerol and methanol). To determine the water and cryoprotectant permeabilities of Symbiodinium, uptake of radio-labeled glycerol and heavy water (D(2)O) were measured. The three different Symbiodinium subtypes studied demonstrated remarkable similarities in their morphology, sensitivity to cryoprotectants and permeability characteristics; however, they differed greatly in their sensitivity to hypo- and hyposmotic challenges and sensitivity to chilling, suggesting that standard slow freezing cryopreservation may not work well for all Symbiodinium. An appendix describes our H(2)O:D(2)O water exchange experiments and compares the diffusionally determined permeability with the two parameter model osmotic permeability.
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Antozoos/microbiología , Criopreservación , Dinoflagelados/fisiología , Animales , Permeabilidad de la Membrana Celular , Conservación de los Recursos Naturales , Criopreservación/métodos , Crioprotectores/farmacocinética , Crioprotectores/toxicidad , Óxido de Deuterio , Dinoflagelados/clasificación , Dinoflagelados/efectos de los fármacos , Glicerol/farmacocinética , Glicerol/toxicidad , Presión Osmótica , Especificidad de la Especie , SimbiosisRESUMEN
A project of the 15th International Histocompatibility Workshop examined the rarity of human leukocyte antigen (HLA) alleles. A section was constructed in the website, www.allelefrequencies.net to contain this data from different sources. A mechanism to search the data was implemented for use by any individual.
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Alelos , Biología Computacional , Antígenos HLA/genética , Bases de Datos Factuales , HumanosRESUMEN
BACKGROUND: Two of the problems of malaria parasite vector control in Nigeria are the diversity of Anopheline vectors and large size of the country. Anopheline distribution and transmission dynamics of malaria were therefore compared between four ecotypes in Nigeria during the rainy season. METHODS: Polymerase chain reaction (PCR) was used in molecular identification after morphological identification microscopically. Enzyme linked immunosorbent assay (ELISA) was used for the blood meal analysis and sporozoite detection. RESULTS: Five species were identified out of 16,410 anophelines collected. An. gambiae s.s made up approximately 29.2%-36.6% of the population in each zone. All five species acted as vectors for P. falciparum. An. gambiae s.s had the highest sporozoite rate. The most infected mosquitoes were found in the rain forest. More blood meals were taken from bovids, except the savannah forest, where 73.3% were on humans and Human Blood index (HBI) was 57.3%. The Entomological inoculation rate (EIR) was a mean of 13.6 ib/p but was highest in the rainforest zone. CONCLUSIONS AND LIMITATIONS: This study demonstrates the complex distribution of anophelines and the considerable variations in the intensity of malaria transmission in Nigeria. We highlight the need to consider diverse epidemiological situations when planning countrywide control programmes.
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Anopheles/fisiología , Insectos Vectores/fisiología , Malaria Falciparum/transmisión , Plasmodium falciparum/aislamiento & purificación , Animales , Anopheles/clasificación , Anopheles/parasitología , Ecología , Ecosistema , Enfermedades Endémicas , Ensayo de Inmunoadsorción Enzimática , Conducta Alimentaria , Humanos , Mordeduras y Picaduras de Insectos , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Nigeria/epidemiología , Plasmodium falciparum/genética , Reacción en Cadena de la Polimerasa , Estaciones del Año , Esporozoítos/parasitologíaRESUMEN
Volatile sulfur compounds such as alkylmercaptans are undesired impurities in natural gas streams. As a result, natural gas treatment and purification services are essential in many industries that utilize natural gas either as a fuel or in a chemical process. While there are many analytical methods that can be employed for the measurement of mercaptans, a simple, practical, and easy-to-implement method is required for remote field deployment. An analytical method, based on multi-dimensional gas chromatography (MDGC), capillary flow technology and flame ionization has been successfully developed for the application described. Results based on the technique showed alkylmercaptans can be accurately measured with a minimum detection limit of 200 ppb (v/v) or better, a linear range of up to 100 ppm (v/v), and a relative standard deviation (n=10) of 1.2% or less were obtained by manual injection with a total sample-to-sample analysis time of less than 15 min.
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Cromatografía de Gases/métodos , Combustibles Fósiles/análisis , Compuestos de Sulfhidrilo/análisis , Ionización de Llama/métodosRESUMEN
Background: Two of the problems of malaria parasite vector control in Nigeria are the diversity of Anopheline vectors and large size of the country. Anopheline distribution and transmission dynamics of malaria were therefore compared between four ecotypes in Nigeria during the rainy season. Methods: Polymerase chain reaction (PCR) was used in molecular identification after morphological identification microscopically. Enzyme linked immunorsorbent assay (ELISA) was used for the blood meal analysis and sporozoite detection. Results: Five species were identified out of 16;410 anophelines collected. An. gambiae s.s made up approximately 29.2-36.6of the population in each zone. All five species acted as vectors for P. falciparum . An. gambiae s.s had the highest sporozoite rate. The most infected mosquitoes were found in the rain forest. More blood meals were taken from bovids; except the savannah forest; where 73.3were on humans and Human Blood index (HBI) was 57.3. The Entomological inoculation rate (EIR) was a mean of 13.6 ib/p but was highest in the rainforest zone. Conclusions and limitations: This study demonstrates the complex distribution of anophelines and the considerable variations in the intensity of malaria transmission in Nigeria. We highlight the need to consider diverse epidemiological situations when planning countrywide control programmes
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Anopheles , Insectos Vectores , Malaria , Plasmodium falciparumRESUMEN
We are still inadequately prepared for an influenza pandemic due to the lack of a vaccine effective for subtypes to which the majority of the human population has no prior immunity and which could be produced rapidly in sufficient quantities. There is therefore an urgent need to investigate novel vaccination approaches. Using a combination of genomic and traditional tools, this study compares the protective efficacy in macaques of an intrarespiratory live influenza virus vaccine produced by truncating NS1 in the human influenza A/Texas/36/91 (H1N1) virus with that of a conventional vaccine based on formalin-killed whole virus. After homologous challenge, animals in the live-vaccine group had greatly reduced viral replication and pathology in lungs and reduced upper respiratory inflammation. They also had lesser induction of innate immune pathways in lungs and of interferon-sensitive genes in bronchial epithelium. This postchallenge response contrasted with that shortly after vaccination, when more expression of interferon-sensitive genes was observed in bronchial cells from the live-vaccine group. This suggested induction of a strong innate immune response shortly after vaccination with the NS1-truncated virus, followed by greater maturity of the postchallenge immune response, as demonstrated with robust influenza virus-specific CD4+ T-cell proliferation, immunoglobulin G production, and transcriptional induction of T- and B-cell pathways in lung tissue. In conclusion, a single respiratory tract inoculation with an NS1-truncated influenza virus was effective in protecting nonhuman primates from homologous challenge. This protection was achieved in the absence of significant or long-lasting adverse effects and through induction of a robust adaptive immune response.
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Sistema Inmunológico/virología , Orthomyxoviridae/genética , Orthomyxoviridae/metabolismo , Proteínas no Estructurales Virales/química , Animales , Biopsia , Sangre/virología , Bronquios/patología , Bronquios/virología , Linfocitos T CD4-Positivos/metabolismo , Epitelio/virología , Femenino , Regulación Viral de la Expresión Génica , Subtipo H1N1 del Virus de la Influenza A/metabolismo , Macaca , Masculino , Transcripción Genética , Proteínas no Estructurales Virales/fisiologíaRESUMEN
BACKGROUND: Hypertriglyceridaemia is a recognised metabolic abnormality in HIV-infected people, increasing in severity in people treated with highly active antiretroviral therapy (HAART). An alternative treatment for hypertriglyceridaemia in non-HIV-infected populations is omega-3 fatty acid supplementation. This study aimed to compare the effectiveness of omega-3 fatty acid supplementation and placebo in lowering fasting triglyceride levels in HIV-infected patients on HAART. METHODS: A placebo-controlled, randomised, double-blind trial in participants on stable HAART with fasting triglycerides of >3.5 mm to 10.0 mm using 9 g of omega-3 fatty acids versus placebo (olive oil) after a 6-week lead in on dietary therapy. RESULTS: Eleven patients were enrolled. The mean triglyceride level for the population decreased from 5.02 mm at baseline to 4.44 mm (-11.6%) after dietary intervention and 3.37 mm (-32.9%) after the 8-week treatment period. In the omega-3 fatty acid arm of the study, triglycerides fell from 5.34 mm to 5.02 mm (-6%) after dietary intervention and to 2.30 mm (-56.9%) after the treatment period. In the placebo arm of the study, triglycerides fell from 4.77 mm to 4.05 mm (-15.1%) after dietary intervention and to 4.08 mm (-14.5%) after the treatment period. Using the random effects model, a statistically significant effect on triglycerides of omega-3 fatty acid versus placebo was found (chi(2) = 6.04, P = 0.0487). The estimated difference between groups for change in mean triglycerides over 8 weeks was -2.32 mm (95% CI -4.52, -0.12 mm). CONCLUSIONS: Omega-3 fatty acids are likely to be an effective treatment for hypertriglyceridaemia in HIV-infected males on HAART.
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Ácidos Grasos Omega-3/uso terapéutico , Infecciones por VIH/complicaciones , Hipertrigliceridemia/tratamiento farmacológico , Adulto , Terapia Antirretroviral Altamente Activa , Distribución de Chi-Cuadrado , Método Doble Ciego , Infecciones por VIH/diagnóstico , Humanos , Hipertrigliceridemia/etiología , Masculino , Resultado del Tratamiento , Carga ViralRESUMEN
Recent outbreaks of avian influenza in humans have stressed the need for an improved nonhuman primate model of influenza pathogenesis. In order to further develop a macaque model, we expanded our previous in vivo genomics experiments with influenza virus-infected macaques by focusing on the innate immune response at day 2 postinoculation and on gene expression in affected lung tissue with viral genetic material present. Finally, we sought to identify signature genes for early infection in whole blood. For these purposes, we infected six pigtailed macaques (Macaca nemestrina) with reconstructed influenza A/Texas/36/91 virus and three control animals with a sham inoculate. We sacrificed one control and two experimental animals at days 2, 4, and 7 postinfection. Lung tissue was harvested for pathology, gene expression profiling, and proteomics. Blood was collected for genomics every other day from each animal until the experimental endpoint. Gross and microscopic pathology, immunohistochemistry, viral gene expression by arrays, and/or quantitative real-time reverse transcription-PCR confirmed successful yet mild infections in all experimental animals. Genomic experiments were performed using macaque-specific oligonucleotide arrays, and high-throughput proteomics revealed the host response to infection at the mRNA and protein levels. Our data showed dramatic differences in gene expression within regions in influenza virus-induced lesions based on the presence or absence of viral mRNA. We also identified genes tightly coregulated in peripheral white blood cells and in lung tissue at day 2 postinoculation. This latter finding opens the possibility of using gene expression arrays on whole blood to detect infection after exposure but prior to onset of symptoms or shedding.
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Gripe Humana/genética , Gripe Humana/virología , Macaca nemestrina/genética , Macaca nemestrina/virología , Animales , Modelos Animales de Enfermedad , Expresión Génica , Perfilación de la Expresión Génica , Genes Virales , Genómica , Humanos , Inmunidad Innata , Virus de la Influenza A/genética , Virus de la Influenza A/inmunología , Virus de la Influenza A/patogenicidad , Gripe Humana/inmunología , Gripe Humana/patología , Pulmón/metabolismo , Pulmón/patología , Pulmón/virología , Macaca nemestrina/inmunología , Masculino , Modelos Biológicos , Proteómica , Factores de TiempoRESUMEN
Coral species throughout the world are facing severe environmental pressures. Because of this, we began cryobiological studies on the sperm of the mushroom coral, Fungia scutaria. We determined that F. scutaria sperm had a mean length of 56 microm and head diameter of 2.5 microm, and a mean spontaneous ice nucleation temperature of -37.2 +/- 1.7 degrees C. When the sperm were exposed to the cryoprotectant glycerol for 5 or 20 min (at 10% v/v), no fertilized larvae were produced. However, when sperm were exposed for 20 min to propylene glycol (10% v/v), fertilizations were produced at the same rate as untreated control eggs and sperm (P > 0.05), but slightly less for dimethyl sulfoxide (10% v/v) (P < 0.05). Regardless, dimethyl sulfoxide caused less osmotic damage to the sperm membrane than did propylene glycol. Therefore, we used the dimethyl sulfoxide (10% v/v) to develop cryopreservation protocols that yielded good post-thaw morphology and motility (>95%) for coral sperm.
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Antozoos , Criopreservación , Espermatozoides , Animales , Crioprotectores/farmacología , Dimetilsulfóxido/farmacología , Fertilización/efectos de los fármacos , Glicerol/farmacología , Masculino , Propilenglicol/farmacología , Espermatozoides/efectos de los fármacos , Espermatozoides/fisiologíaRESUMEN
The tapeworm Ligula intestinalis occurs in the body cavity of its cyprinid second intermediate host, in this study the roach Rutilus rutilus, and inhibits host gonadal development. The mechanism by which infected fish are prevented from reproducing is unknown. Comparison of parameters, such as body length and weight, and condition factor and age, between infected and uninfected individuals, indicated only minor effects of parasitism on growth and condition. In contrast, seasonal gonadal development, as observed in uninfected fish, did not occur in infected fish, and gonads remained small and blocked at the primary oocyte stage in female roach. As immature ovaries and testes are still present, the parasite is presumed to act upon the brain-pituitary-gonadal axis of the fish to inhibit further development of reproductive organs. We investigated the Ligula/fish interaction at the level of the pituitary gland by determination of gonadotrophin (LH) content using a heterologous RIA for carp (Cyprinus carpio) LHbeta subunit. The results indicated that the pituitary glands of infected roach contained approximately 50% less LH than non-infected fish. After the cloning and sequencing of roach LHbeta subunit, we measured roach LHbeta mRNA levels by real-time RT-PCR. A corresponding 50% reduction in LHbeta mRNA pituitary levels was determined. These results reflect a significant and measurable effect of parasitism on the pituitary gland, and lend support to the hypothesis that excretory/secretory products released from the parasite interact with the brain-pituitary-gonadal axis of the fish host and thus inhibit gonadal development.
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Cestodos/fisiología , Cyprinidae/parasitología , Hormona Luteinizante/metabolismo , Animales , Carga Corporal (Radioterapia) , Cyprinidae/fisiología , Femenino , Interacciones Huésped-Parásitos , Hormona Luteinizante/genética , Oocitos/citología , Hipófisis/metabolismo , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estaciones del Año , Maduración SexualRESUMEN
Alternative donor sources include non-heart-beating donors (NHBDs). There donors have been exposed to significant ischemia, so that it is common to utilize machine perfusion to either improve the organs or at least assess their viability. Both prolonged warm ischemia and machine perfusion can potentially damage the vascular endothelium, thereby exposing vimentin to antigenic recognition. The aim of this study was to determine whether anti-vimentin antibodies could be detected in the blood of renal transplant recipients at specific time points after transplant and whether they could be related to the donor source. Fifty-one recipients of NHBD kidneys were compared to 52 recipients of heart-beating donor (HBD) kidneys. All recipients had similar anti-vimentin levels pretransplant. However, at 1 month those kidneys from Maastricht category II NHB donors showed significantly higher levels. At 6 months both Maastricht category II and category III NHB donor recipients displayed significantly higher levels than recipients of HBD kidneys.
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Autoanticuerpos/sangre , Trasplante de Riñón/fisiología , Riñón/inmunología , Donantes de Tejidos , Vimentina/inmunología , Adulto , Creatinina/sangre , Femenino , Paro Cardíaco , Frecuencia Cardíaca , Prueba de Histocompatibilidad , Humanos , Trasplante de Riñón/inmunología , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Streptokinase is used for preflush for non-heart-beating donors (NHBDs) in our center. The aim of this study was to evaluate whether the use of thrombolytic streptokinase results in the production of anti-streptokinase antibodies in the recipients after renal transplantation. Recipient sera taken prior to and at 1 and 6 months posttransplant were tested for the presence of antibodies to streptokinase using an enzyme-linked immunosorbent assay assay. No differences were detected between a group of 18 recipients who had kidneys from thrombolytic-treated NHBDs and a further group of 18 who received NHBD kidneys without such treatment.