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1.
PLoS Genet ; 18(4): e1010099, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35446841

RESUMEN

East Coast fever, a tick-borne cattle disease caused by the Theileria parva parasite, is among the biggest natural killers of cattle in East Africa, leading to over 1 million deaths annually. Here we report on the genetic analysis of a cohort of Bos indicus (Boran) cattle demonstrating heritable tolerance to infection with T. parva (h2 = 0.65, s.e. 0.57). Through a linkage analysis we identify a 6 Mb genomic region on bovine chromosome 15 that is significantly associated with survival outcome following T. parva exposure. Testing this locus in an independent cohort of animals replicates this association with survival following T. parva infection. A stop gained variant in a paralogue of the FAF1 gene in this region was found to be highly associated with survival across both related and unrelated animals, with only one of the 20 homozygote carriers (T/T) of this change succumbing to the disease in contrast to 44 out of 97 animals homozygote for the reference allele (C/C). Consequently, we present a genetic locus linked to tolerance of one of Africa's most important cattle diseases, raising the promise of marker-assisted selection for cattle that are less susceptible to infection by T. parva.


Asunto(s)
Enfermedades de los Bovinos , Theileria parva , Theileria , Theileriosis , Proteínas Adaptadoras Transductoras de Señales/genética , Alelos , Animales , Proteínas Reguladoras de la Apoptosis/genética , Bovinos , Enfermedades de los Bovinos/genética , Humanos , Theileria/genética , Theileria parva/genética , Theileriosis/genética , Theileriosis/parasitología
2.
Genet Sel Evol ; 55(1): 91, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097935

RESUMEN

BACKGROUND: The genomes of indigenous African cattle are composed of components with Middle Eastern (taurine) and South Asian (indicine) origins, providing a valuable model to study hybridization and to identify genetic barriers to gene flow. In this study, we analysed indigenous African cattle breeds as models of hybrid zones, considering taurine and indicine samples as ancestors. In a genomic cline analysis of whole-genome sequence data, we considered over 8 million variants from 144 animals, which allows for fine-mapping of potential genomic incompatibilities at high resolution across the genome. RESULTS: We identified several thousand variants that had significantly steep clines ('SCV') across the whole genome, indicating restricted introgression. Some of the SCV were clustered into extended regions, with the longest on chromosome 7, spanning 725 kb and including 27 genes. We found that variants with a high phenotypic impact (e.g. indels, intra-genic and missense variants) likely represent greater genetic barriers to gene flow. Furthermore, our findings provide evidence that a large proportion of breed differentiation in African cattle could be linked to genomic incompatibilities and reproductive isolation. Functional evaluation of genes with SCV suggest that mitonuclear incompatibilities and genes associated with fitness (e.g. resistance to paratuberculosis) could account for restricted gene flow in indigenous African cattle. CONCLUSIONS: To our knowledge, this is the first time genomic cline analysis has been applied to identify restricted introgression in the genomes of indigenous African cattle and the results provide extended insights into mechanisms (e.g. genomic incompatibilities) contributing to hybrid differentiation. These results have important implications for our understanding of genetic incompatibilities and reproductive isolation and provide important insights into the impact of cross-breeding cattle with the aim of producing offspring that are both hardy and productive.


Asunto(s)
Genoma , Genómica , Animales , Bovinos/genética , Hibridación Genética , Flujo Génico , Polimorfismo de Nucleótido Simple
3.
J Immunol ; 199(8): 2794-2802, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28904125

RESUMEN

Peptides offer enormous promise as vaccines to prevent and protect against many infectious and noninfectious diseases. However, to date, limited vaccine efficacy has been reported and none have been licensed for human use. Innovative ways to enhance their immunogenicity are being tested, but rational sequence modification as a means to improve immune responsiveness has been neglected. Our objective was to establish a two-step generic protocol to modify defined amino acids of a helical peptide epitope to create a superior immunogen. Peptide variants of p145, a conserved helical peptide epitope from the M protein of Streptococcus pyogenes, were designed by exchanging one amino acid at a time, without altering their α-helical structure, which is required for correct antigenicity. The immunogenicities of new peptides were assessed in outbred mice. Vaccine efficacy was assessed in a skin challenge and invasive disease model. Out of 86 variants of p145, seven amino acid substitutions were selected and made the basis of the design for 18 new peptides. Of these, 13 were more immunogenic than p145; 7 induced Abs with significantly higher affinity for p145 than Abs induced by p145 itself; and 1 peptide induced more than 10,000-fold greater protection following challenge than the parent peptide. This peptide also only required a single immunization (compared with three immunizations with the parent peptide) to induce complete protection against invasive streptococcal disease. This study defines a strategy to rationally improve the immunogenicity of peptides and will have broad applicability to the development of vaccines for infectious and noninfectious diseases.


Asunto(s)
Antígenos Bacterianos/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Portadoras/metabolismo , Fragmentos de Péptidos/metabolismo , Infecciones Estreptocócicas/inmunología , Vacunas Estreptocócicas/inmunología , Streptococcus pyogenes/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Humanos , Inmunidad Humoral , Inmunización , Ratones , Ratones Endogámicos BALB C , Mutación/genética , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/inmunología , Ingeniería de Proteínas , Infecciones Estreptocócicas/prevención & control , Vacunas de Subunidad
4.
BMC Med ; 16(1): 184, 2018 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-30293531

RESUMEN

BACKGROUND: The continuing morbidity and mortality associated with infection with malaria parasites highlights the urgent need for a vaccine. The efficacy of sub-unit vaccines tested in clinical trials in malaria-endemic areas has thus far been disappointing, sparking renewed interest in the whole parasite vaccine approach. We previously showed that a chemically attenuated whole parasite asexual blood-stage vaccine induced CD4+ T cell-dependent protection against challenge with homologous and heterologous parasites in rodent models of malaria. METHODS: In this current study, we evaluated the immunogenicity and safety of chemically attenuated asexual blood-stage Plasmodium falciparum (Pf) parasites in eight malaria-naïve human volunteers. Study participants received a single dose of 3 × 107 Pf pRBC that had been treated in vitro with the cyclopropylpyrolloindole analogue, tafuramycin-A. RESULTS: We demonstrate that Pf asexual blood-stage parasites that are completely attenuated are immunogenic, safe and well tolerated in malaria-naïve volunteers. Following vaccination with a single dose, species and strain transcending Plasmodium-specific T cell responses were induced in recipients. This included induction of Plasmodium-specific lymphoproliferative responses, T cells secreting the parasiticidal cytokines, IFN-γ and TNF, and CD3+CD45RO+ memory T cells. Pf-specific IgG was not detected. CONCLUSIONS: This is the first clinical study evaluating a whole parasite blood-stage malaria vaccine. Following administration of a single dose of completely attenuated Pf asexual blood-stage parasites, Plasmodium-specific T cell responses were induced while Pf-specific antibodies were not detected. These results support further evaluation of this chemically attenuated vaccine in humans. TRIAL REGISTRATION: Trial registration: ACTRN12614000228684 . Registered 4 March 2014.


Asunto(s)
Vacunas contra la Malaria/inmunología , Malaria Falciparum/prevención & control , Vacunas Atenuadas/inmunología , Adulto , Animales , Anticuerpos Antiprotozoarios/inmunología , Humanos , Inmunidad Celular/inmunología , Masculino , Proyectos Piloto , Plasmodium falciparum/inmunología , Linfocitos T/inmunología , Vacunación/métodos
5.
PLoS Pathog ; 12(12): e1006122, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28027314

RESUMEN

The immunobiology underlying the slow acquisition of skin immunity to group A streptococci (GAS), is not understood, but attributed to specific virulence factors impeding innate immunity and significant antigenic diversity of the type-specific M-protein, hindering acquired immunity. We used a number of epidemiologically distinct GAS strains to model the development of acquired immunity. We show that infection leads to antibody responses to the serotype-specific determinants on the M-protein and profound protective immunity; however, memory B cells do not develop and immunity is rapidly lost. Furthermore, antibodies do not develop to a conserved M-protein epitope that is able to induce immunity following vaccination. However, if re-infected with the same strain within three weeks, enduring immunity and memory B-cells (MBCs) to type-specific epitopes do develop. Such MBCs can adoptively transfer protection to naïve recipients. Thus, highly protective M-protein-specific MBCs may never develop following a single episode of pyoderma, contributing to the slow acquisition of immunity and to streptococcal endemicity in at-risk populations.


Asunto(s)
Memoria Inmunológica/inmunología , Piodermia/inmunología , Piodermia/microbiología , Infecciones Estreptocócicas/inmunología , Infecciones Estreptocócicas/microbiología , Animales , Ensayo de Inmunoadsorción Enzimática , Ratones , Streptococcus pyogenes
6.
Xenotransplantation ; 25(1)2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29067741

RESUMEN

In addition to immune barriers, molecular incompatibilities between species are predicted to limit pig liver survival in primate xenotransplantation models. Assessment and measurement of synthetic function of genetically modified porcine livers after ex vivo perfusion with human blood have not previously been described. Eight porcine livers from α1,3-galactosyl transferase knockout and human membrane cofactor (GalTKO.hCD46), six livers from GalTKO.hCD46 and N-glycolylneuraminic acid knockout (GalTKO.hCD46.Neu5GcKO), and six livers from GalTKO.hCD46 with humanized decay-accelerating factor (hCD55), endothelial protein C receptor (hEPCR), tissue factor pathway inhibitor (hTFPI), and integrin-associated protein (hCD47) (GalTKO.hCD46.hCD55.hEPCR.hTFPI.hCD47) pigs were perfused with human blood under physiologic conditions. Timed blood samples were tested for liver enzymes and for pig-specific albumin production via Western blot. Porcine albumin levels increased with time in all experiments. By densitometry, GalTKO.hCD46.Neu5GcKO livers had the highest albumin levels, measured both as total produced, and when controlled for perfusion duration, compared to GalTKO.hCD46 (P = .068) and GalTKO.hCD46.hCD55.hEPCR.hTFPI.hCD47 livers (P = .04). Porcine livers perfused with human blood demonstrated the synthetic ability to produce albumin in all cases. GalTKO.hCD46.Neu5GcKO pig livers demonstrated the most robust albumin production. This suggests that the Neu5GcKO phenotype provides a protective effect on the graft due to decreased human antibody recognition and graft injury.


Asunto(s)
Supervivencia de Injerto/inmunología , Hígado/inmunología , Trasplante de Pulmón , Trasplante Heterólogo , Animales , Animales Modificados Genéticamente , Antígenos CD55/genética , Circulación Extracorporea/métodos , Técnicas de Inactivación de Genes , Humanos , Hígado/metabolismo , Trasplante de Pulmón/métodos , Proteína Cofactora de Membrana/genética , Proteína Cofactora de Membrana/inmunología , Porcinos
7.
J Surg Res ; 222: 34-38, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29273373

RESUMEN

BACKGROUND: Although single-port donor nephrectomy offers improved cosmetic outcomes, technical challenges have limited its application to selected centers. Our center has performed over 400 single-port donor nephrectomies. The da Vinci single-site robotic platform was utilized in an effort to overcome the steric, visualization, ergonomic, and other technical limitations associated with the single-port approach. MATERIALS AND METHODS: Food and Drug Administration device exemption was obtained. Selection criteria for kidney donation included body mass index <35, left kidney donors, and ≤2 renal arteries. After colonic mobilization using standard single-port techniques, the robotic approach was utilized for ureteral complex and hilar dissection. RESULTS: Three cases were performed using the robotic single-site platform. Average total operative time was 262 ±â€¯42 min including 82 ±â€¯16 min of robotic use. Docking time took 20 ±â€¯10 min. Blood loss averaged 77 ±â€¯64 mL. No intraoperative complications occurred, and all procedures were completed with our standard laparoscopic single-port approach. CONCLUSIONS: This is the first clinical experience of robotic-assisted donor nephrectomy utilizing the da Vinci single-site platform. Our experience supported the safety of this approach but found that the technology added cost and complexity without tangible benefit. Development of articulating instruments, energy, and stapling devices will be necessary for increased application of robotic single-site surgery for donor nephrectomy.


Asunto(s)
Laparoscopía/métodos , Nefrectomía/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Adulto , Femenino , Humanos , Donadores Vivos , Persona de Mediana Edad
8.
J Immunol ; 196(8): 3364-74, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26969753

RESUMEN

Cluster of virulence responder/sensor (CovR/S) mutant group A streptococci (GAS) are serious human pathogens of multiple M protein strains that upregulate expression of virulence factors, including the IL-8 proteaseStreptococcus pyogenescell envelope proteinase (SpyCEP), thus blunting neutrophil-mediated killing and enabling ingress of bacteria from a superficial wound to deep tissue. We previously showed that a combination vaccine incorporating J8-DT (conserved peptide vaccine from the M protein) and a recombinant SpyCEP fragment protects against CovR/S mutants. To enhance the vaccine's safety profile, we identified a minimal epitope (S2) that was the target for anti-SpyCEP Abs that could protect IL-8 from SpyCEP-mediated proteolysis. Abs from healthy humans and from mice experimentally infected with GAS also recognized S2, albeit at low titers. Native SpyCEP may be poorly immunogenic (cryptic or subdominant), and it would be to the organism's advantage if the host did not induce a strong Ab response against it. However, S2 conjugated to diphtheria toxoid is highly immunogenic and induces Abs that recognize and neutralize SpyCEP. Hence, we describe a two-component peptide vaccine that induces Abs (anti-S2) that protect IL-8 from proteolysis and other Abs (anti-J8) that cause strain-independent killing in the presence of neutrophils. We show that either component alone is ineffectual in preventing skin infection and bacteremia due to CovR/S mutants but that the combination induces complete protection. This protection correlated with a significant influx of neutrophils to the infection site. The data strongly suggest that the lack of natural immunity to hypervirulent GAS strains in humans could be rectified by this combination vaccine.


Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas Portadoras/inmunología , Péptido Hidrolasas/inmunología , Infecciones Estreptocócicas/inmunología , Vacunas Estreptocócicas/inmunología , Streptococcus pyogenes/inmunología , Animales , Anticuerpos Antibacterianos/inmunología , Bacteriemia/inmunología , Bacteriemia/microbiología , Bacteriemia/prevención & control , Proteínas Bacterianas/inmunología , Toxoide Diftérico/inmunología , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Neutrófilos/inmunología , Péptido Hidrolasas/biosíntesis , Péptido Hidrolasas/genética , Piel/microbiología , Enfermedades Cutáneas Bacterianas/inmunología , Enfermedades Cutáneas Bacterianas/microbiología , Enfermedades Cutáneas Bacterianas/prevención & control , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/prevención & control , Streptococcus pyogenes/patogenicidad , Vacunas de Subunidad/inmunología , Vacunas Sintéticas/inmunología , Factores de Virulencia/biosíntesis , Factores de Virulencia/genética , Factores de Virulencia/inmunología
9.
Xenotransplantation ; 24(6)2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28940313

RESUMEN

BACKGROUND: Wild-type pigs express several carbohydrate moieties on their cell surfaces that differ from those expressed by humans. This difference in profile leads to pig tissue cell recognition of human blood cells causing sequestration, in addition to antibody-mediated xenograft injury. One such carbohydrate is N-glycolylneuraminic acid (Neu5Gc), a sialic acid molecule synthesized in pigs but not in humans. Here, we evaluate livers with and without Neu5Gc in an ex vivo liver xeno perfusion model. METHODS: Livers from pigs with an α1,3-galactosyl transferase gene knockout (GalTKO) and transgenic for human membrane cofactor (hCD46) with (n = 5) or without (n = 7) an additional Neu5Gc gene knock out (Neu5GcKO) were perfused ex vivo with heparinized whole human blood. A drug regimen consisting of a histamine inhibitor, thromboxane synthase inhibitor, and a murine anti-human GPIb-blocking antibody fragment was given to half of the experiments in each group. RESULTS: Liver function tests (AST and ALT) were not significantly different between livers with and without the Neu5GcKO. GalTKO.hCD46.Neu5GcKO livers had less erythrocyte sequestration as evidenced by a higher mean hematocrit over time compared to GalTKO.hCD46 livers (P = .0003). The addition of Neu5GcKO did not ameliorate profound thrombocytopenia seen within the first 15 minutes of perfusion. TXB2 was significantly less with the added drug regimen (P = .006) or the presence of Neu5GcKO (P = .017). CONCLUSIONS: The lack of Neu5Gc expression attenuated erythrocyte loss but did not prevent profound early onset thrombocytopenia or platelet activation, although TXB2 levels were decreased in the presence of Neu5GcKO.


Asunto(s)
Galactosiltransferasas/genética , Xenoinjertos/efectos de los fármacos , Ácidos Neuramínicos/farmacología , Trasplante Heterólogo , Animales , Animales Modificados Genéticamente , Técnicas de Inactivación de Genes/métodos , Supervivencia de Injerto/inmunología , Humanos , Proteína Cofactora de Membrana/genética , Porcinos , Trombocitopenia/terapia
10.
Transpl Int ; 30(11): 1132-1139, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28672056

RESUMEN

The single-port approach has been associated with an unacceptably high rate of umbilical port hernias in large series of patients undergoing single-port cholecystectomy and colectomy and with additional surgical risks thought secondary to technical and ergonomic limitations. A retrospective review of 378 consecutive laparoendoscopic single-site(LESS) donor nephrectomies performed between 04/15/2009 and 04/09/2014 was conducted. Twelve patients (3%) developed an umbilical hernia. Eleven (92%) were female and eight (73%) of these patients had a prior pregnancy. Hernias were reported 13.5 ± 6.9 months after donation, and the mean size was 5.1 ± 3.7 cm. Seven additional cases (1.9%) required a return to the operating room for internal hernia (2), evisceration (1), bleeding (1), enterotomy (1), and wound infection (2). The original incision was utilized for reexploration. One patient required emergent conversion to an open procedure for bleeding during the initial donation. There were no mortalities. Recipient patient and graft survival were 99% and 99% at 1 year, respectively. Although reports associated with earlier experiences with single-site procedures suggested an unacceptably high rate of hernias at the surgical site, this does not seem to be the case at our center. This technique is a reliable surgical technique for left donor nephrectomy at this institution.


Asunto(s)
Nefrectomía/efectos adversos , Adulto , Endoscopía , Femenino , Hernia Umbilical/etiología , Humanos , Laparoscopía , Masculino , Persona de Mediana Edad , Nefrectomía/métodos , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos
11.
Neurocase ; 23(1): 41-51, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28376695

RESUMEN

Amyloid-positron emission tomography (PET) imaging of the brain detects elevated amyloid-beta (amyloid-ß) neuritic plaques in vivo, which can be helpful in appropriately selected cases of mild cognitive impairment (MCI) and dementia, when Alzheimer's disease remains a possible etiology, after a comprehensive clinical evaluation. We reviewed cases of cognitively impaired patients who underwent amyloid-PET imaging because of diagnostic uncertainty. Pre- and post-PET elements of diagnosis and management were first compared, to assess impact of scan results on clinical decision-making, and then an analysis of those decisions was undertaken in appropriate clinical situations, to delineate the added value and limitations of amyloid-PET imaging. The potential benefits and limitations of this diagnostic tool are important to understand in an era when the utility of such scans in clinical practice is evolving.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/metabolismo , Demencia/diagnóstico por imagen , Demencia/metabolismo , Tomografía de Emisión de Positrones , Anciano , Compuestos de Anilina/metabolismo , Glicoles de Etileno/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
BMC Neurol ; 15: 146, 2015 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-26289075

RESUMEN

BACKGROUND: Although there are studies investigating the pathologic origins of mild cognitive impairment (MCI), they have revolved around comparisons to normal elderly individuals or those with Alzheimer's disease (AD) or other dementias. There are few studies directly comparing the comprehensive neuropathology of amnestic (aMCI) and nonamnestic (naMCI) MCI. METHODS: The database of the Brain and Body Donation Program ( www.brainandbodydonationprogram.org ), a longitudinal clinicopathological study of normal aging and neurodegenerative disorders, was queried for subjects who were carrying a diagnosis of aMCI or naMCI at the time of autopsy. Neuropathological lesions, including neuritic plaques, neurofibrillary tangles (NFTs), Lewy bodies (LBs), infarcts, cerebral white matter rarefaction (CWMR), cerebral amyloid angiopathy (CAA), and concurrent major clinicopathological diagnoses, including Parkinson's disease (PD) were analyzed. RESULTS: Thirty four subjects with aMCI and 15 naMCI met study criteria. Subjects with aMCI were older at death (88 vs. 83 years of age, p = 0.03). Individuals with naMCI had higher densities of LBs within the temporal lobe (p = 0.04) while subjects with aMCI had a propensity for increased NFTs in parietal and temporal lobes (p values = 0.07). After adjusting for age at death, the only significant difference was greater densities of temporal lobe NFTs within the aMCI group. Other regional pathology scores for plaques, NFTs, and LBs were similar between groups. Subjects met clinico-pathological criteria for co-existent PD in 24 % aMCI and 47 % naMCI while neuropathological criteria for AD were met in equal percentages of aMCI and of naMCI cases (53 %); these proportional differences were not significant (p values > 0.35). Furthermore, regardless of amnestic status, there was a greater presence of CAA (71 % of MCI with executive dysfunction vs. 39 % without p = 0.03) and a greater presence of CWMR (81 % of MCI with executive dysfunction and 54 % without p = 0.046) in MCI cases with executive dysfunction. CONCLUSIONS: No single pathologic entity strongly dichotomized MCI groups, perhaps due to the pathologic heterogeneity found within both entities. However, these data suggest the possibility for naMCI to have a propensity for increased LBs and aMCI for increased NFTs in select anatomic regions.


Asunto(s)
Amnesia/patología , Encéfalo/patología , Disfunción Cognitiva/patología , Cuerpos de Lewy/patología , Ovillos Neurofibrilares/patología , Placa Amiloide/patología , Anciano , Anciano de 80 o más Años , Amnesia/complicaciones , Angiopatía Amiloide Cerebral/complicaciones , Angiopatía Amiloide Cerebral/patología , Infarto Cerebral/complicaciones , Infarto Cerebral/patología , Disfunción Cognitiva/complicaciones , Femenino , Humanos , Leucoencefalopatías/complicaciones , Leucoencefalopatías/patología , Masculino , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/patología , Lóbulo Temporal/patología
13.
Neuropathology ; 35(4): 354-89, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25619230

RESUMEN

The Brain and Body Donation Program (BBDP) at Banner Sun Health Research Institute (http://www.brainandbodydonationprogram.org) started in 1987 with brain-only donations and currently has banked more than 1600 brains. More than 430 whole-body donations have been received since this service was commenced in 2005. The collective academic output of the BBDP is now described as the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). Most BBDP subjects are enrolled as cognitively normal volunteers residing in the retirement communities of metropolitan Phoenix, Arizona. Specific recruitment efforts are also directed at subjects with Alzheimer's disease, Parkinson's disease and cancer. The median age at death is 82. Subjects receive standardized general medical, neurological, neuropsychological and movement disorders assessments during life and more than 90% receive full pathological examinations by medically licensed pathologists after death. The Program has been funded through a combination of internal, federal and state of Arizona grants as well as user fees and pharmaceutical industry collaborations. Subsets of the Program are utilized by the US National Institute on Aging Arizona Alzheimer's Disease Core Center and the US National Institute of Neurological Disorders and Stroke National Brain and Tissue Resource for Parkinson's Disease and Related Disorders. Substantial funding has also been received from the Michael J. Fox Foundation for Parkinson's Research. The Program has made rapid autopsy a priority, with a 3.0-hour median post-mortem interval for the entire collection. The median RNA Integrity Number (RIN) for frozen brain and body tissue is 8.9 and 7.4, respectively. More than 2500 tissue requests have been served and currently about 200 are served annually. These requests have been made by more than 400 investigators located in 32 US states and 15 countries. Tissue from the BBDP has contributed to more than 350 publications and more than 200 grant-funded projects.


Asunto(s)
Envejecimiento/patología , Encéfalo/patología , Enfermedades Neurodegenerativas/patología , Bancos de Tejidos , Obtención de Tejidos y Órganos , Anciano de 80 o más Años , Arizona , Autopsia , Biomarcadores , Femenino , Humanos , Masculino , Preservación de Órganos , Cambios Post Mortem , Donantes de Tejidos , Supervivencia Tisular
14.
Alzheimers Dement ; 11(8): 994-1004, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25849033

RESUMEN

INTRODUCTION: Down syndrome (DS) is associated with amyloid b (Ab) deposition. METHODS: We characterized imaging measurements of regional fibrillar Ab burden, cerebral metabolic rate for glucose (rCMRgl), gray matter volumes (rGMVs), and age associations in 5 DS with dementia (DS/AD1), 12 DS without dementia (DS/AD2), and 9 normal controls (NCs). RESULTS: There were significant group differences in mean standard uptake value ratios (SUVRs) for florbetapir with DS/AD1 having the highest, followed by DS/AD2, followed by NC. For [18F]-fluorodeoxyglucose positron emission tomography, posterior cingulate rCMRgl in DS/AD1 was significantly reduced compared with DS/AD2 and NC. For volumetric magnetic resonance imaging (vMRI), hippocampal volumes were significantly reduced for the DS/AD1 compared with DS/AD2 and NC. Age-related SUVR increases and rCMRgl reductions were greater in DS participants than in NCs. DISCUSSION: DS is associated with fibrillar Ab, rCMRgl, and rGMV alterations in the dementia stage and before the presence of clinical decline. This study provides a foundation for the studies needed to inform treatment and prevention in DS.


Asunto(s)
Compuestos de Anilina/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Síndrome de Down/patología , Glicoles de Etileno/metabolismo , Fluorodesoxiglucosa F18/metabolismo , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Adulto , Enfermedad de Alzheimer/complicaciones , Síndrome de Down/complicaciones , Servicios de Urgencia Psiquiátrica , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
15.
Conserv Biol ; 28(3): 756-62, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24423254

RESUMEN

Habitat linkages can help maintain connectivity of animal populations in developed landscapes. However, the lack of empirical data on the width of lateral movements (i.e., the zigzagging of individuals as they move from one point to point another) makes determining the width of such linkages challenging. We used radiotracking data from wood frogs (Lithobates sylvaticus) and spotted salamanders (Ambystoma maculatum) in a managed forest in Maine (U.S.A.) to characterize movement patterns of populations and thus inform planning for the width of wildlife corridors. For each individual, we calculated the polar coordinates of all locations, estimated the vector sum of the polar coordinates, and measured the distance from each location to the vector sum. By fitting a Gaussian distribution over a histogram of these distances, we created a population-level probability density function and estimated the 50th and 95th percentiles to determine the width of lateral movement as individuals progressed from the pond to upland habitat. For spotted salamanders 50% of lateral movements were ≤13 m wide and 95% of movements were ≤39 m wide. For wood frogs, 50% of lateral movements were ≤17 m wide and 95% of movements were ≤ 51 m wide. For both species, those individuals that traveled the farthest from the pond also displayed the greatest lateral movement. Our results serve as a foundation for spatially explicit conservation planning for pond-breeding amphibians in areas undergoing development. Our technique can also be applied to movement data from other taxa to aid in designing habitat linkages.


Asunto(s)
Ambystoma/fisiología , Migración Animal , Conservación de los Recursos Naturales , Ranidae/fisiología , Animales , Ecosistema , Maine , Estanques
16.
Nat Commun ; 14(1): 8167, 2023 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-38071303

RESUMEN

Translational control in pathogenic bacteria is fundamental to gene expression and affects virulence and other infection phenotypes. We used an enhanced ribosome profiling protocol coupled with parallel transcriptomics to capture accurately the global translatome of two evolutionarily distant pathogenic bacteria-the Gram-negative bacterium Salmonella and the Gram-positive bacterium Listeria. We find that the two bacteria use different mechanisms to translationally regulate protein synthesis. In Salmonella, in addition to the expected correlation between translational efficiency and cis-regulatory features such as Shine-Dalgarno (SD) strength and RNA secondary structure around the initiation codon, our data reveal an effect of the 2nd and 3rd codons, where the presence of tandem lysine codons (AAA-AAA) enhances translation in both Salmonella and E. coli. Strikingly, none of these features are seen in efficiently translated Listeria transcripts. Instead, approximately 20% of efficiently translated Listeria genes exhibit 70 S footprints seven nt upstream of the authentic start codon, suggesting that these genes may be subject to a novel translational initiation mechanism. Our results show that SD strength is not a direct hallmark of translational efficiency in all bacteria. Instead, Listeria has evolved additional mechanisms to control gene expression level that are distinct from those utilised by Salmonella and E. coli.


Asunto(s)
Listeria , Biosíntesis de Proteínas , Biosíntesis de Proteínas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , ARN Mensajero/metabolismo , Listeria/genética , Codón/metabolismo , Codón Iniciador/metabolismo , Bacterias/genética , Iniciación de la Cadena Peptídica Traduccional/genética
17.
Genome Biol ; 24(1): 127, 2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-37218021

RESUMEN

BACKGROUND: Understanding the variation between well and poorly adapted cattle breeds to local environments and pathogens is essential for breeding cattle with improved climate and disease-resistant phenotypes. Although considerable progress has been made towards identifying genetic differences between breeds, variation at the epigenetic and chromatin levels remains poorly characterized. Here, we generate, sequence and analyse over 150 libraries at base-pair resolution to explore the dynamics of DNA methylation and chromatin accessibility of the bovine immune system across three distinct cattle lineages. RESULTS: We find extensive epigenetic divergence between the taurine and indicine cattle breeds across immune cell types, which is linked to the levels of local DNA sequence divergence between the two cattle sub-species. The unique cell type profiles enable the deconvolution of complex cellular mixtures using digital cytometry approaches. Finally, we show distinct sub-categories of CpG islands based on their chromatin and methylation profiles that discriminate between classes of distal and gene proximal islands linked to discrete transcriptional states. CONCLUSIONS: Our study provides a comprehensive resource of DNA methylation, chromatin accessibility and RNA expression profiles of three diverse cattle populations. The findings have important implications, from understanding how genetic editing across breeds, and consequently regulatory backgrounds, may have distinct impacts to designing effective cattle epigenome-wide association studies in non-European breeds.


Asunto(s)
Cromatina , Epigenoma , Animales , Bovinos/genética , Fenotipo , Islas de CpG , Polimorfismo de Nucleótido Simple
18.
Clin Neuropsychol ; 36(6): 1589-1598, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33019876

RESUMEN

Objective: To provide normative data and examine form equivalency of the Brief Visuospatial Memory Test-Revised (BVMT-R) in a sample of 9th decade adults. Method: The sample was comprised of 90 healthy individuals ages 80-84 (n = 42) and 85-89 (n = 48). The average years of education was 14.8 (2.4). The BVMT-R Forms 1 and 4 were administered in a counterbalanced order, one week apart. Form equivalency was conducted utilizing Analysis of Variance (ANOVA). Results: There were no significant gender, education, or MMSE differences between the two age groups or between the counterbalanced subgroups. There were no significant differences between Forms 1 and 4 for the 80-84 age group. However, BVMT-R Form 1 Trial 1 and Total Recall raw scores were significantly higher than those for Form 4 in the 85-89 age group. Conclusions: Individuals in their early 80s obtained comparable scores on Forms 1 and 4 of the BVMT-R; however, individuals in their late 80 s showed more difficulty learning and recalling information presented in Form 4 compared to Form 1. It is recommended that clinicians consider form-specific normative data with this population.


Asunto(s)
Memoria , Recuerdo Mental , Adulto , Anciano de 80 o más Años , Cognición , Humanos , Pruebas Neuropsicológicas
19.
PLoS One ; 17(9): e0267333, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36178939

RESUMEN

Marine Spatial Planning (MSP) provides a process that uses spatial data and models to evaluate environmental, social, economic, cultural, and management trade-offs when siting (i.e., strategically locating) ocean industries. Aquaculture is the fastest-growing food sector in the world. The United States (U.S.) has substantial opportunity for offshore aquaculture development given the size of its exclusive economic zone, habitat diversity, and variety of candidate species for cultivation. However, promising aquaculture areas overlap many protected species habitats. Aquaculture siting surveys, construction, operations, and decommissioning can alter protected species habitat and behavior. Additionally, aquaculture-associated vessel activity, underwater noise, and physical interactions between protected species and farms can increase the risk of injury and mortality. In 2020, the U.S. Gulf of Mexico was identified as one of the first regions to be evaluated for offshore aquaculture opportunities as directed by a Presidential Executive Order. We developed a transparent and repeatable method to identify aquaculture opportunity areas (AOAs) with the least conflict with protected species. First, we developed a generalized scoring approach for protected species that captures their vulnerability to adverse effects from anthropogenic activities using conservation status and demographic information. Next, we applied this approach to data layers for eight species listed under the Endangered Species Act, including five species of sea turtles, Rice's whale, smalltooth sawfish, and giant manta ray. Next, we evaluated four methods for mathematically combining scores (i.e., Arithmetic mean, Geometric mean, Product, Lowest Scoring layer) to generate a combined protected species data layer. The Product approach provided the most logical ordering of, and the greatest contrast in, site suitability scores. Finally, we integrated the combined protected species data layer into a multi-criteria decision-making modeling framework for MSP. This process identified AOAs with reduced potential for protected species conflict. These modeling methods are transferable to other regions, to other sensitive or protected species, and for spatial planning for other ocean-uses.


Asunto(s)
Ecosistema , Elasmobranquios , Animales , Acuicultura , Conservación de los Recursos Naturales/métodos , Especies en Peligro de Extinción , Golfo de México
20.
Vet Immunol Immunopathol ; 230: 110126, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33080530

RESUMEN

The CD4+/CD8+ ratio is used as a marker of the immune regulation of T cell balance. When the ratio in peripheral blood is less than 1, this is considered an indication of immune suppression in an individual. Previous work on bovine Peripheral Blood Mononuclear Cells (PBMC) has consistently reported a ratio ≥1 as seen in other mammalian hosts, i.e. higher circulating CD4+ cell numbers than CD8+ cell numbers. However, a consistent inverted CD4+/CD8+ ratio (<1) was observed in Boran cattle, an African Bos indicus breed. The T cell populations were characterized in Boran cattle (n = 52), revealing higher percentages of circulating CD8+ cells (31.9 % average) than CD4+ cells (19.1 % average), thus resulting in the inversion of the expected T cell homeostasis in these animals. The results show that this inversion is not an effect of age or relatedness of the cattle, rather, it was shared by almost all Boran cattle used in this study. Despite this inversion being a feature shared by both males and females, the female cattle had significantly higher CD4+/CD8+ ratios than the male Boran. This paper describes the characteristics of the T cell fractions in the study animals and compares the findings to those of other Boran cattle in Kenya, and four other cattle breeds representing African indicine, African taurine, Brazilian indicine and European taurine cattle. We demonstrate that the consistent observation of inverted CD4+/CD8+ cell ratio was restricted to the Boran.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Bovinos/inmunología , Animales , Peso Corporal , Recuento de Células , Femenino , Kenia , Leucocitos Mononucleares/inmunología , Masculino
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