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We describe for the first time the co-existence of the parallel and antiparallel conformation of the heterodimeric E3/K3 and E3/R3 coiled-coil systems in solution. The introduction of a furanylated amino acid in the (EIAALEK)3 sequence allowed, upon photo-induced covalent crosslinking, freezing of the respective coiled-coil complexes present in solution. The occurrence of both parallel and antiparallel conformations in solution was supported by computational simulations and further confirmed by fluorescence experiments based on pyrene-pyrene stacking.
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We experimentally investigate the spectral broadening in fused silica in the multiphoton absorption regime. Under standard conditions of laser irradiation, linear polarization of laser pulses is more advantageous for supercontinuum generation. However, with high non-linear absorption, we observe more efficient spectral broadening for circular polarizations for both Gaussian and doughnut-shaped beams. The multiphoton absorption in fused silica is studied by measuring the total transmission of laser pulses and by the intensity dependence of the self-trapped exciton luminescence observation. The strong polarization dependence of multiphoton transitions fundamentally affects the broadening of the spectrum in solids.
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Age-related decline in skeletal muscle structure and function can be mitigated by regular exercise. However, the precise mechanisms that govern this are not fully understood. The nucleus plays an active role in translating forces into biochemical signals (mechanotransduction), with the nuclear lamina protein lamin A regulating nuclear shape, nuclear mechanics and ultimately gene expression. Defective lamin A expression causes muscle pathologies and premature ageing syndromes, but the roles of nuclear structure and function in physiological ageing and in exercise adaptations remain obscure. Here, we isolated single muscle fibres and carried out detailed morphological and functional analyses on myonuclei from young and older exercise-trained individuals. Strikingly, myonuclei from trained individuals were more spherical, less deformable, and contained a thicker nuclear lamina than those from untrained individuals. Complementary to this, exercise resulted in increased levels of lamin A and increased myonuclear stiffness in mice. We conclude that exercise is associated with myonuclear remodelling, independently of age, which may contribute to the preservative effects of exercise on muscle function throughout the lifespan. KEY POINTS: The nucleus plays an active role in translating forces into biochemical signals. Myonuclear aberrations in a group of muscular dystrophies called laminopathies suggest that the shape and mechanical properties of myonuclei are important for maintaining muscle function. Here, striking differences are presented in myonuclear shape and mechanics associated with exercise, in both young and old humans. Myonuclei from trained individuals were more spherical, less deformable and contained a thicker nuclear lamina than untrained individuals. It is concluded that exercise is associated with age-independent myonuclear remodelling, which may help to maintain muscle function throughout the lifespan.
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Silk is a unique, remarkably strong biomaterial made of simple protein building blocks. To date, no synthetic method has come close to reproducing the properties of natural silk, due to the complexity and insufficient understanding of the mechanism of the silk fiber formation. Here, we use a combination of bulk analytical techniques and nanoscale analytical methods, including nano-infrared spectroscopy coupled with atomic force microscopy, to probe the structural characteristics directly, transitions, and evolution of the associated mechanical properties of silk protein species corresponding to the supramolecular phase states inside the silkworm's silk gland. We found that the key step in silk-fiber production is the formation of nanoscale compartments that guide the structural transition of proteins from their native fold into crystalline ß-sheets. Remarkably, this process is reversible. Such reversibility enables the remodeling of the final mechanical characteristics of silk materials. These results open a new route for tailoring silk processing for a wide range of new material formats by controlling the structural transitions and self-assembly of the silk protein's supramolecular phases.
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Fibroínas , Seda , Seda/química , Materiales Biocompatibles/química , Microscopía de Fuerza Atómica , Espectrofotometría Infrarroja , Fibroínas/químicaRESUMEN
In this placebo-controlled phase II randomized clinical trial, 103 human immunodeficiency virus type 1 (HIV-1)-infected patients under cART (combined antiretroviral treatment) were randomized 2:1 to receive either 3 doses of DNA GTU-MultiHIV B (coding for Rev, Nef, Tat, Gag, and gp160) at week 0 (W0), W4, and W12, followed by 2 doses of LIPO-5 vaccine containing long peptides from Gag, Pol, and Nef at W20 and W24, or placebo. Analytical treatment interruption (ATI) was performed between W36 to W48. At W28, vaccinees experienced an increase in functional CD4+ T-cell responses (P < 0.001 for each cytokine compared to W0) measured, predominantly against Gag and Pol/Env, and an increase in HIV-specific CD8+ T cells producing interleukin 2 (IL-2) and tumor necrosis factor alpha (TNF-α) (P = 0.001 and 0.013, respectively), predominantly against Pol/Env and Nef. However, analysis of T-cell subsets by mass cytometry in a subpopulation showed an increase in the W28/W0 ratio for memory CD8+ T cells coexpressing exhaustion and senescence markers such as PD-1/TIGIT (P = 0.004) and CD27/CD57 (P = 0.044) in vaccinees compared to the placebo group. During ATI, all patients experienced viral rebound, with the maximum observed HIV RNA level at W42 (median, 4.63 log10 copies [cp]/ml; interquartile range [IQR], 4.00 to 5.09), without any difference between arms. No patient resumed cART for CD4 cell count drop. Globally, the vaccine strategy was safe. However, a secondary HIV transmission during ATI was observed. These data show that the prime-boost combination of DNA and LIPO-5 vaccines elicited broad and polyfunctional T cells. The contrast between the quality of immune responses and the lack of potent viral control underscores the need for combined immunomodulatory strategies. (This study has been registered at ClinicalTrials.gov under registration no. NCT01492985.)IMPORTANCE In this placebo-controlled phase II randomized clinical trial, we evaluated the safety and immunogenicity of a therapeutic prime-boost vaccine strategy using a recombinant DNA vaccine (GTU-MultiHIV B clade) followed by a boost vaccination with a lipopeptide vaccine (HIV-LIPO-5) in HIV-infected patients on combined antiretroviral therapy. We show here that this prime-boost strategy is well tolerated, consistently with previous studies in HIV-1-infected individuals and healthy volunteers who received each vaccine component individually. Compared to the placebo group, vaccinees elicited strong and polyfunctional HIV-specific CD4+ and CD8+ T-cell responses. However, these immune responses presented some qualitative defects and were not able to control viremia following antiretroviral treatment interruption, as no difference in HIV viral rebound was observed in the vaccine and placebo groups. Several lessons were learned from these results, pointing out the urgent need to combine vaccine strategies with other immune-based interventions.
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Vacunas contra el SIDA , Antirretrovirales/uso terapéutico , Infecciones por VIH/terapia , Vacunas de ADN , Vacunas contra el SIDA/administración & dosificación , Vacunas contra el SIDA/inmunología , Adulto , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Femenino , Infecciones por VIH/inmunología , VIH-1/efectos de los fármacos , Humanos , Inmunización Secundaria , Masculino , Persona de Mediana Edad , Vacunas de ADN/administración & dosificación , Vacunas de ADN/inmunologíaAsunto(s)
Betacoronavirus/genética , Infecciones por Coronavirus/diagnóstico , Laboratorios , Neumonía Viral/diagnóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Betacoronavirus/aislamiento & purificación , COVID-19 , Niño , Preescolar , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/genética , Estudios Transversales , Femenino , Francia/epidemiología , Humanos , Lactante , Recién Nacido , Laboratorios/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/sangre , Neumonía Viral/epidemiología , Neumonía Viral/genética , Valor Predictivo de las Pruebas , Sector Privado/normas , Sector Privado/estadística & datos numéricos , Práctica Profesional/estadística & datos numéricos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/normas , SARS-CoV-2 , Estudios Seroepidemiológicos , Adulto JovenRESUMEN
Animal models are a key element in disease research and treatment. In the field of neuropsychiatric lupus research, inbred, transgenic and disease-induced mice provide an opportunity to study the pathogenic routes of this multifactorial illness. In addition to achieving a better understanding of the immune mechanisms underlying the disease onset, supplementary metabolic and endocrine influences have been discovered and investigated. The ever-expanding knowledge about the pathologic events that occur at disease inception enables us to explore new drugs and therapeutic approaches further and to test them using the same animal models. Discovery of the molecular targets that constitute the pathogenic basis of the disease along with scientific advancements allow us to target these molecules with monoclonal antibodies and other specific approaches directly. This novel therapy, termed "targeted biological medication" is a promising endeavor towards producing drugs that are more effective and less toxic. Further work to discover additional molecular targets in lupus' pathogenic mechanism and to produce drugs that neutralize their activity is needed to provide patients with safe and efficient methods of controlling and treating the disease.
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Modelos Animales de Enfermedad , Vasculitis por Lupus del Sistema Nervioso Central/patología , Animales , Animales Modificados Genéticamente , Autoanticuerpos/metabolismo , Citocinas/metabolismo , Predisposición Genética a la Enfermedad , Humanos , Vasculitis por Lupus del Sistema Nervioso Central/genética , Vasculitis por Lupus del Sistema Nervioso Central/metabolismo , RatonesRESUMEN
Autoimmune reaction after vaccination is sporadically reported in the medical literature. Vaccinations are generally safe and have an important role in eradicating endemic diseases worldwide. Nevertheless, the question arises as to whether there is a possibility of post-vaccination autoimmune phenomena. The anti-tetanus vaccine is being used since 1924, and it is part of the recommended immunization schedules for children. There are few reports of autoimmune diseases, such as rheumatoid arthritis and anti-phospholipid syndrome after anti-tetanus vaccination. Herein, we describe four cases, of which we believe, show a clear temporal relation between anti-tetanus vaccination and the appearance of dermatomyositis, systemic lupus erythematosus, type 1 diabetes mellitus and anti-phospholipid syndrome. We also suggest some of the pathogenic mechanisms that promote a pathogenic autoimmune response.
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Enfermedades Autoinmunes/etiología , Toxoide Tetánico/efectos adversos , Adolescente , Adulto , Autoinmunidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vacunación/efectos adversosRESUMEN
Mutations of several genes have been implicated in autosomal recessive osteopetrosis (OP), a disease caused by impaired function and differentiation of osteoclasts. Severe combined immune deficiencies (SCID) can likewise result from different genetic mutations. We report two siblings with SCID and an atypical phenotype of OP. A biallelic microdeletion encompassing the 5' region of TRAF6, RAG1 and RAG2 genes was identified. TRAF6, a tumor necrosis factor receptor-associated family member, plays an important role in T cell signaling and in RANKL-dependent osteoclast differentiation and activation but its role in human OP has not been previously reported. The RAG proteins are essential for recombination of B and T cell receptors, and for the survival and differentiation of these cells. This is the first study to report a homozygous deletion of TRAF6 as a cause of human disease.
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Proteínas de Unión al ADN/genética , Proteínas de Homeodominio/genética , Proteínas Nucleares/genética , Osteopetrosis/genética , Inmunodeficiencia Combinada Grave/genética , Factor 6 Asociado a Receptor de TNF/genética , Regiones no Traducidas 5'/genética , Diferenciación Celular/genética , Femenino , Predisposición Genética a la Enfermedad , Homocigoto , Humanos , Lactante , Recién Nacido , Péptidos y Proteínas de Señalización Intracelular , Masculino , Mutación , Osteoclastos/metabolismo , Osteopetrosis/patología , Receptores de Antígenos de Linfocitos T/genética , Eliminación de Secuencia/genética , Inmunodeficiencia Combinada Grave/patología , Transducción de Señal/genéticaRESUMEN
Fetal edema can present as limited subcutaneous edema, fluid accumulation in body cavities or hydrops fetalis. Hydrops fetalis is the end stage of a variety of fetal/maternal disorders and nonimmune etiology represents more than 3/4 of cases. Lymphatic dysplasia may account for a subset of patients with nonimmune and "idiopathic" hydrops fetalis, fetal chylous ascites or chylothorax. We present two unrelated patients with antenatal features of hereditary lymphedema syndrome, in whom Milroy disease was diagnosed after birth. At least, 20 genes have been identified to cause primary lymphedema, with sometimes antenatal features. Hereditary lymphedema syndrome should be considered in cases of nonimmune hydrops fetalis/fetal edema after ruling out the more common etiologies.
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Hidropesía Fetal/diagnóstico por imagen , Linfedema/diagnóstico por imagen , Receptor 3 de Factores de Crecimiento Endotelial Vascular/genética , Adulto , Femenino , Humanos , Hidropesía Fetal/genética , Recién Nacido , Linfedema/genética , Masculino , Mutación Missense , Embarazo , Ultrasonografía PrenatalRESUMEN
AIMS: This study addresses the common practice of providing aggressive treatments of limited clinical benefit and cost-effectiveness to seriously ill and frail elderly. We have created a statistical model of 6-month mortality risk prediction following acute hospitalisation admission, and identified a subset of patients with poorest prognosis that requires comfort-focused care. METHODS: We have studied electronic medical records of 26,937 patients age 65 years or older, hospitalised in the internal medicine departments of one tertiary-care teaching medical center in Northern Israel from January 1, 2008 through December 31, 2011 and mortality data from the Israeli Internal Ministry Registry. Norton score records were employed for the performance status evaluation. Multivariate logistic regression analysis was used to predict the risk of 6-month mortality. RESULTS: Variables associated with an increased risk of 6-month mortality included: metastatic cancer, age above 85 years, decreased values of blood albumin and haemoglobin, increased blood urea nitrogen and decreased physical/mental status and activity. The receiver operating characteristic area for the predicted probability of death was 0.845 and 0.847 in external validation cohort. Using predictive values of the logistic regression analysis, the study cohort was stratified into six groups with various predictive mortality risks. CONCLUSION: The majority of deaths that have occurred within 6 months following the acute hospitalisation could be predicted on patient admission based on a few simple and easily obtained parameters. Earlier recognition of patients nearing the end of their lives may lead to better care and more efficient use of available resource.
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Enfermedad Aguda/mortalidad , Mortalidad Hospitalaria , Medición de Riesgo/métodos , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Anciano Frágil , Humanos , Medicina Interna/estadística & datos numéricos , Israel/epidemiología , Modelos Logísticos , Masculino , Atención Dirigida al Paciente/métodos , Valor Predictivo de las Pruebas , Pronóstico , Factores de RiesgoRESUMEN
Massive loss of lamina propria CD4(+) T cells, changes in the lymphatic architecture, and altered intestinal epithelial barrier leading to microbial translocation are the common features of HIV-1 infection and are not fully restored under combined antiretroviral therapy (cART). To better understand determinants of gut mucosal restoration, we have performed phenotypic and gene expression analyses of the gut from HIV-infected patients, naive or treated with cART initiated either at the early phase of the primary infection or later during the chronic phase. We found a depletion of T helper type 22 (Th22) and interleukin-17-producing cells in naive patients. These populations, except Th22 cells, were not restored under cART. Regulatory T cells/Th17 ratio was significantly increased in HIV-infected patients and was inversely correlated to the restoration of CD4(+) T cells but not to gut HIV DNA levels. Gene profile analysis of gut mucosal distinguished two groups of patients, which fitted with the timing of cART initiation. In their majority early, but not later treated patients, exhibited conserved intestinal lymphoid structure, epithelial barrier integrity and dendritic cell maturation pathways. Our data demonstrate that early initiation of cART helps to preserve and/or restore lymphoid gut mucosal homeostasis and provide a rationale for initiating cART during the acute phase of HIV infection.
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Antirretrovirales/uso terapéutico , Células Dendríticas/efectos de los fármacos , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Intestinos/efectos de los fármacos , Linfocitos T Reguladores/efectos de los fármacos , Células Th17/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , ADN Viral/sangre , Células Dendríticas/inmunología , Células Dendríticas/virología , Progresión de la Enfermedad , Quimioterapia Combinada , Femenino , Perfilación de la Expresión Génica , Infecciones por VIH/inmunología , VIH-1/fisiología , Humanos , Inmunidad Mucosa/efectos de los fármacos , Interleucinas/metabolismo , Intestinos/inmunología , Intestinos/virología , Masculino , Persona de Mediana Edad , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/virología , Células Th17/inmunología , Células Th17/virología , Resultado del Tratamiento , Interleucina-22RESUMEN
We have previously shown that green tea (GT) drinking combined with vitamin E supplementation reduced plasma protein carbonyls and increased erythrocytes catalase activity in exercising healthy elderly. In the present study we set out to investigate the antioxidative effects of GT drinking in an aging population. We performed an interventional, crossover, controlled prospective trial with 35 healthy elderly subjects (mean age 67.3±4.8 years), supplemented with four daily placebo maltodextrin "tea-bags" for 12 weeks, followed by four 1.5 g daily GT bags for another 12 weeks. Data were obtained at baseline, at the end of the placebo period, and at the end of the GT intervention period. We found that GT did not alter erythrocyte catalase activity. However, it provided protection against 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced oxidative hemolysis which declined by 10.2% (p<0.001). No changes were observed in saliva oral peroxidase enzymes. Nonetheless, saliva total antioxidant capacity increased by 42.0% (p<0.01). Plasma oxidative products, such as protein carbonyls, lipid peroxides and thiobarbituric acid reactive substances (TBARS) were stable throughout the intervention period. We conclude that four daily cups of GT are well tolerated in elderly free living subjects. Our results demonstrate that both erythrocyte resistances to oxidation and saliva antioxidant capacity are improved by GT drinking. The clinical implications of these oxidation modifications require further research.
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Envejecimiento/sangre , Antioxidantes/metabolismo , Eritrocitos/metabolismo , Saliva/química , Té , Anciano , Amidinas/farmacología , Células Cultivadas , Estudios Cruzados , Eritrocitos/efectos de los fármacos , Femenino , Humanos , Peroxidación de Lípido , Masculino , Persona de Mediana Edad , Oxidantes/farmacología , Oxidación-Reducción , Peroxidasas/metabolismo , Estudios Prospectivos , Carbonilación Proteica , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismoRESUMEN
The long-term spontaneous evolution of humans and the human immunodeficiency virus (HIV) is not well characterized; many vertebrate species, including humans, exhibit remnants of other retroviruses in their genomes that question such possible endogenization of HIV. We investigated two HIV-infected patients with no HIV-related disease and no detection with routine tests of plasma HIV RNA or cell-associated HIV DNA. We used Sanger and deep sequencing to retrieve HIV DNA sequences integrated in the human genome and tested the host humoral and cellular immune responses. We noticed that viruses from both patients were inactivated by the high prevalence of the transformation of tryptophan codons into stop codons (25% overall (3-100% per gene) and 24% overall (0-50% per gene)). In contrast, the humoral and/or cellular responses were strong for one patient and moderate for the other, indicating that a productive infection occurred at one stage of the infection. We speculate that the stimulation of APOBEC, the enzyme group that exchanges G for A in viral nucleic acids and is usually inhibited by the HIV protein Vif, has been amplified and made effective from the initial stage of the infection. Furthermore, we propose that a cure for HIV may occur through HIV endogenization in humans, as observed for many other retroviruses in mammals, rather than clearance of all traces of HIV from human cells, which defines viral eradication.
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ADN Viral/genética , Retrovirus Endógenos/genética , Infecciones por VIH/virología , VIH/genética , Provirus/genética , Codón sin Sentido , Codón de Terminación , Estudios de Cohortes , Retrovirus Endógenos/aislamiento & purificación , VIH/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Provirus/aislamiento & purificación , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
OBJECTIVES: Interleukin-2 (IL-2) therapy increased CD4 cell counts and delayed antiretroviral therapy (ART) initiation in HIV-infected patients in the Agence Nationale de Recherche sur le SIDA et les Hépatites Virales (ANRS) 119 trial. However, four cases of lymphoma were reported. Epstein-Barr virus (EBV) replication is associated with an increased risk of lymphoma in immunocompromised patients. We assessed whether IL-2 had an impact on EBV replication and the development of lymphoma. METHODS: A total of 130 ART-naïve patients were randomized to receive IL-2 therapy (n = 66) or no treatment (n = 64). Clinical data for patients with lymphomas were reviewed and tumours assessed for evidence of EBV infection and CD25 (the IL-2 receptor) expression. EBV DNA levels were measured in whole blood and plasma in both arms using real-time polymerase chain reaction (PCR), up to 48 weeks after baseline (BL). RESULTS: Four lymphomas occurred, a median of 61 weeks [range 40-94 weeks] after randomization at a median CD4 cell count of 396 cells/µL (IQR 234-536 cells/µL). In the IL-2 arm, two patients developed EBV-positive Hodgkin's lymphoma, and one developed EBV-negative Burkitt-type lymphoma. One patient in the control group developed EBV-positive non-Hodgkin's lymphoma. CD25 was negative in all cases. Among the 41 of 55 (control arm) and 44 of 58 (IL-2 arm) patients with detectable EBV DNA in whole blood at both BL and week 48, the median change in EBV DNA between BL and week 48 was +0.04 log10 copies/ml in both arms (P = 0.7). In plasma, EBV was detected at least once in 22 of 52 controls and 21 of 54 IL-2-treated patients (P = 0.8). CONCLUSIONS: IL-2 therapy had no significant effect on EBV replication over 48 weeks in these ART-naïve patients. The occurrence of lymphomas did not seem to be associated with IL-2 therapy.
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Fármacos Anti-VIH/uso terapéutico , Linfoma de Burkitt/virología , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Herpesvirus Humano 4/genética , Enfermedad de Hodgkin/virología , Interleucina-2/uso terapéutico , Adulto , Fármacos Anti-VIH/efectos adversos , Linfoma de Burkitt/sangre , Recuento de Linfocito CD4 , ADN Viral/sangre , ADN Viral/efectos de los fármacos , Infecciones por Virus de Epstein-Barr/sangre , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/virología , Femenino , Infecciones por VIH/complicaciones , Herpesvirus Humano 4/aislamiento & purificación , Enfermedad de Hodgkin/sangre , Humanos , Incidencia , Interleucina-2/efectos adversos , Masculino , Persona de Mediana Edad , Carga Viral/efectos de los fármacosRESUMEN
Cassava mosaic disease (CMV), caused by one or a combination of cassava mosaic geminiviruses, is ranked among the most important constraints to profitable and efficient production of cassava. Effective control measures require in-depth knowledge of the viral causative agent. Using rolling-circle amplification and unique enzymes, the full genome of two species of cassava mosaic geminivirus isolated from infected cassava plants in Ghana were cloned into pCambia 1300 and pET-28b. The sequences of the genome were determined on an ABI sequencer and a pairwise comparison was performed with other cassava-infecting geminiviruses from different countries. It was revealed that cassava grown in Ghana is attacked by two species of geminivirus in either single or mixed infections. These are the African cassava mosaic virus (ACMV) and the East African cassava mosaic virus (EACMV)-like, with high sequence similarity of 94% and 80%, respectively, between the DNA-A and DNA-B components of each virus, and 66% and 41% similarity of the common region (CR) (for A and B accordingly). The DNA-A of ACMV and EACMV-like contained 2781 and 2800 nucleotides, respectively, while their DNA-B components had 2725 and 2734 nucleotides, respectively. ACMV DNA-A was over 97% similar to those of other ACMVs from the continent. In contrast, EACMV-like DNA-A was over 98% similar to the isolates from Cameroon and other West African countries, and less than 88% similar to other EACMV species. Thus ACMV and EACMV-like were named African cassava mosaic virus-Ghana and East African cassava mosaic Cameroon virus-Ghana. Computer analysis revealed that their genome arrangement follows the typical old world bipartite begomovirus genome. The association of these two species and their interaction might account for the severe symptoms observed on infected plants in the field and in the greenhouse.
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Begomovirus/genética , Begomovirus/aislamiento & purificación , Genoma Viral , Manihot/virología , Enfermedades de las Plantas/virología , Secuencia de Bases , Begomovirus/clasificación , Ghana , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADNRESUMEN
The Mediterranean population of the green sea turtle Chelonia mydas is critically endangered. Genetic analysis of this population using the ordinary haplotyping system, based on sequence analysis of a segment of the mitochondrial DNA (mtDNA) D-loop (control region), revealed very little variation. The most common haplotype, CM-A13, was observed in all but three individuals in hundreds of samples in previous studies. In search for a more informative marker we sequenced the 3' of the mitochondrial control region which contains an AT-rich microsatellite. We found a unique pattern that consists of four AT short tandem repeats (STRs) with varying copy numbers. This allowed us to construct a new haplotyping system composed of four different STR sizes for each mtDNA sequence. Our new mitochondrial STR (mtSTR) haplotyping approach revealed 33 different haplotypes within the nesting and stranded sea turtles along the Mediterranean Israeli seashore. The Israeli coast nesting females had 10 different haplotypes that can be used for monitoring and conservation purposes. The mtSTR haplotyping system can clearly assist in fingerprinting of individual turtles. Moreover, it can be used for estimating phylogenetic distances within populations. This case study shows that the mtSTR haplotyping is applicable for the study of global green sea turtle populations and could also be considered as markers of genetic variability in other species.
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ADN Mitocondrial/genética , Repeticiones de Microsatélite/genética , Tortugas/genética , Animales , Secuencia de Bases , Análisis por Conglomerados , Ecosistema , Femenino , Haplotipos , Israel , Mar Mediterráneo , Datos de Secuencia Molecular , Polimorfismo Genético , Alineación de Secuencia/veterinaria , Tortugas/clasificaciónRESUMEN
BACKGROUND: The immune deficiency of human immunodeficiency virus (HIV) infection is not fully corrected with ARV therapy. Interleukin-7 (IL-7) can boost CD4 T-cell counts, but optimal dosing and mechanisms of cellular increases need to be defined. METHODS: We performed a randomized placebo-controlled dose escalation (10, 20 and 30 µg/kg) trial of 3 weekly doses of recombinant human IL-7 (rhIL-7) in ARV-treated HIV-infected persons with CD4 T-cell counts between 101 and 400 cells/µL and plasma HIV levels <50 copies/mL. Toxicity, activity and the impact of rhIL-7 on immune reconstitution were monitored. RESULTS: Doses of rhIL-7 up to 20 µg/kg were well tolerated. CD4 increases of predominantly naive and central memory T cells were brisk (averaging 323 cells/µL at 12 weeks) and durable (up to 1 year). Increased cell cycling and transient increased bcl-2 expression were noted. Expanded cells did not have the characteristics of regulatory or activated T cells. Transient low-level HIV viremia was seen in 6 of 26 treated patients; modest increases in total levels of intracellular HIV DNA were proportional to CD4 T-cell expansions. IL-7 seemed to increase thymic output and tended to improve the T-cell receptor (TCR) repertoire in persons with low TCR diversity. CONCLUSIONS: Three weekly doses of rhIL-7 at 20 µg/kg are well tolerated and lead to a dose-dependent CD4 T-cell increase and the broadening of TCR diversity in some subjects. These data suggest that this rhIL-7 dose could be advanced in future rhIL-7 clinical studies. CLINICAL TRIALS REGISTRATION: NCT0047732.