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1.
J Am Chem Soc ; 142(21): 9587-9593, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32364723

RESUMEN

Chemical reaction networks (CRNs) provide a powerful abstraction to formally represent complex biochemical processes. DNA provides a promising substrate to implement the abstract representation (or programming language) of CRNs due to its programmable nature. Prior works that used DNA to implement CRNs either used DNA-only systems or multienzyme DNA circuits. Architectures with DNA-only components had the rationale of being biologically simple systems. Multienzyme systems, on the other hand, aimed at using natural enzymes to improve circuit performance, although, at the cost of increased complexity. In this work, we explore an alternative architecture that lies along the spectrum in between DNA-only systems and multienzyme DNA systems. Our architecture relies on only a strand displacing polymerase enzyme and DNA hybridization reactions for implementing CRNs. First, we briefly introduce the theory and DNA design of simple CRNs and then explore the fundamental properties of polymerase-based strand displacement systems. Finally, we engineer a catalytic amplifier in vitro as a use-case of our framework since such amplifiers require the intricate design of DNA sequences and reaction conditions.


Asunto(s)
ADN Polimerasa Dirigida por ADN/metabolismo , ADN/metabolismo , Redes y Vías Metabólicas , ADN/química , ADN Polimerasa Dirigida por ADN/química , Hibridación de Ácido Nucleico
2.
Nano Lett ; 19(4): 2668-2673, 2019 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-30896178

RESUMEN

Fluorescence microscopy enables simultaneous observation of the dynamics of single molecules in a large region of interest. Most traditional techniques employ either the geometry or the color of single molecules to uniquely identify (or barcode) different species of interest. However, these techniques require complex sample preparation and multicolor hardware setup. In this work, we introduce a time-based amplification-free single-molecule barcoding technique using easy-to-design nucleic acid strands. A dye-labeled complementary reporter strand transiently binds to the programmed nucleic acid strands to emit temporal intensity signals. We program the DNA strands to emit uniquely identifiable temporal signals for molecular-scale fingerprinting. Since the reporters bind transiently to DNA devices, our method offers relative immunity to photobleaching. We use a single universal reporter strand for all DNA devices making our design extremely cost-effective. We show DNA strands can be programmed for generating a multitude of uniquely identifiable molecular barcodes. Our technique can be easily incorporated with the existing orthogonal methods that use wavelength or geometry to generate a large pool of distinguishable molecular barcodes thereby enhancing the overall multiplexing capabilities of single-molecule imaging.


Asunto(s)
Código de Barras del ADN Taxonómico/métodos , ADN/aislamiento & purificación , ADN/química , Colorantes Fluorescentes/química , Microscopía Fluorescente/métodos , Nanotecnología/métodos , Fotoblanqueo
3.
J Am Chem Soc ; 141(42): 16539-16543, 2019 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-31600065

RESUMEN

DNA is a highly programmable biomolecule and has been used to construct biological circuits for different purposes. An important development of DNA circuits is to process the information on receptors on cell membranes. In this Communication, we introduce an architecture to program localized DNA-based biomolecular reaction networks on cancer cell membranes. Based on our architecture, various types of reaction networks have been experimentally demonstrated, from simple linear cascades to reaction networks of complex structures. These localized DNA-based reaction networks can be used for medical applications such as cancer cell detection. Compared to prior work on DNA circuits for evaluating cell membrane receptors, the DNA circuits made by our architecture have several major advantages including simpler design, lower leak, lower cost, and higher signal-to-background ratio.


Asunto(s)
Membrana Celular/metabolismo , ADN/metabolismo , Aptámeros de Nucleótidos/metabolismo , Línea Celular Tumoral , Humanos
4.
Arch Virol ; 164(3): 767-774, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30663022

RESUMEN

Fecal samples collected from free-ranging Atlantic bottlenose dolphins (BDs) in the Indian River Lagoon of Florida were processed for viral discovery using a next-generation sequencing (NGS) approach. A 693-bp contig identified in the NGS data was nearly identical to the partial L1 gene sequence of a papillomavirus (PV) previously found in a penile papilloma in a killer whale (Orcinus orca). Based on this partial bottlenose dolphin papillomavirus (BDPV) sequence, a nested inverse PCR and primer-walking strategy was employed to generate the complete genome sequence. The full BDPV genome consisted of 7299 bp and displayed a typical PV genome organization. The BDPV E6 protein contained a PDZ-binding motif, which has been shown to be involved in carcinogenic transformation involving high-risk genital human PVs. Screening of 12 individual fecal samples using a specific endpoint PCR assay revealed that the feces from a single female BD displaying a genital papilloma was positive for the BDPV. Genetic analysis indicated that this BDPV (Tursiops truncatus papillomavirus 8; TtPV8) is a new type of Dyopipapillomavirus 1, previously sequenced from an isolate obtained from a penile papilloma in a harbor porpoise (Phocoena phocoena). Although only a partial L1 sequence has been determined for a PV detected in a killer whale genital papilloma, our finding of a nearly identical sequence in an Atlantic BD may indicate that members of this viral species are capable of host jumping. Future work is needed to determine if this virus is a high-risk PV that is capable of inducing carcinogenic transformation and whether it poses a significant health risk to wild delphinid populations.


Asunto(s)
Delfín Mular/virología , Papillomaviridae/genética , Infecciones Tumorales por Virus/veterinaria , Animales , Femenino , Florida , Genómica , Papillomaviridae/clasificación , Papillomaviridae/aislamiento & purificación , Filogenia , Ríos/virología , Infecciones Tumorales por Virus/virología , Proteínas Virales/genética
5.
Small ; : e1801470, 2018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-30022600

RESUMEN

DNA devices have been shown to be capable of evaluating Boolean logic. Several robust designs for DNA circuits have been demonstrated. Some prior DNA-based circuits are use-once circuits since the gate motifs of the DNA circuits get permanently destroyed as a side effect of the computation, and hence cannot respond correctly to subsequent changes in inputs. Other DNA-based circuits use a large reservoir of buffered gates to replace the working gates of the circuit and can be used to drive a finite number of computation cycles. In many applications of DNA circuits, the inputs are inherently asynchronous, and this necessitates that the DNA circuits be asynchronous: the output must always be correct regardless of differences in the arrival time of inputs. This paper demonstrates: 1) renewable DNA circuits, which can be manually reverted to their original state by addition of DNA strands, and 2) time-responsive DNA circuits, where if the inputs change over time, the DNA circuit can recompute the output correctly based on the new inputs, that are manually added after the system has been reset. The properties of renewable, asynchronous, and time-responsiveness appear to be central to molecular-scale systems; for example, self-regulation in cellular organisms.

6.
Small ; 13(12)2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28092433

RESUMEN

Theoretical models of localized DNA hybridization reactions on nanoscale substrates indicate potential benefits over conventional DNA hybridization reactions. Recently, a few approaches have been proposed to speed-up DNA hybridization reactions; however, experimental confirmation and quantification of the acceleration factor have been lacking. Here, a system to investigate localized DNA hybridization reactions on a nanoscale substrate is presented. The system consists of six metastable DNA hairpins that are tethered to a long DNA track. The localized DNA hybridization reaction of the proposed system is triggered by a DNA strand which initiates the subsequent self-assembly. Fluorescence kinetics indicates that the half-time completion of a localized DNA hybridization chain reaction is six times faster than the same reaction in the absence of the substrate. The proposed system provides one of the first known quantification of the speed-up of DNA hybridization reactions due to the locality effect.


Asunto(s)
ADN/genética , Hibridación de Ácido Nucleico/métodos , Secuencia de Bases , ADN/química , Fluorescencia , Cinética , Reproducibilidad de los Resultados
7.
Dis Aquat Organ ; 125(2): 141-153, 2017 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-28737159

RESUMEN

From 2003 to 2015, 360 free-ranging Atlantic bottlenose dolphins Tursiops truncatus inhabiting the Indian River Lagoon (IRL, n = 246), Florida, and coastal waters of Charleston (CHS, n = 114), South Carolina, USA, were captured, given comprehensive health examinations, and released as part of a multidisciplinary and multi-institutional study of individual and population health. The aim of this review is to summarize the substantial health data generated by this study and to examine morbidity between capture sites and over time. The IRL and CHS dolphin populations are affected by complex infectious and neoplastic diseases often associated with immunologic disturbances. We found evidence of infection with cetacean morbillivirus, dolphin papilloma and herpes viruses, Chlamydiaceae, a novel uncultivated strain of Paracoccidioides brasiliensis (recently identified as the causal agent of dolphin lobomycosis/lacaziasis), and other pathogens. This is the first long-term study documenting the various types, progression, seroprevalence, and pathologic interrelationships of infectious diseases in dolphins from the southeastern USA. Additionally, the study has demonstrated that the bottlenose dolphin is a valuable sentinel animal that may reflect environmental health concerns and parallel emerging public health issues.


Asunto(s)
Delfín Mular , Enfermedades Transmisibles/veterinaria , Monitoreo del Ambiente , Animales , Enfermedades Transmisibles/epidemiología , Medición de Riesgo , Sudeste de Estados Unidos/epidemiología
8.
Dis Aquat Organ ; 125(2): 155-166, 2017 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-28737160

RESUMEN

Bottlenose dolphins Tursiops truncatus are the most common apex predators found in coastal and estuarine ecosystems along the southeastern coast of the USA, where these animals are exposed to multiple chemical pollutants and microbial agents. In this review, we summarize the results of investigations of environmental exposures evaluated in 360 free-ranging dolphins between 2003 and 2015. Bottlenose dolphins inhabiting the Indian River Lagoon, Florida (IRL, n = 246), and coastal waters of Charleston, South Carolina (CHS, n = 114), were captured, given comprehensive health examinations, and released as part of a multidisciplinary and multi-institutional study of individual and population health. High concentrations of persistent organic pollutants including legacy contaminants (DDT and other pesticides, polychlorinated biphenyl compounds) as well as 'emerging' contaminants (polybrominated diphenyl ethers, perfluorinated compounds) were detected in dolphins from CHS, with lower concentrations in the IRL. Conversely, the concentrations of mercury in the blood and skin of IRL dolphins were among the highest reported worldwide and approximately 5 times as high as those found in CHS dolphins. A high prevalence of resistance to antibiotics commonly used in humans and animals was detected in bacteria isolated from fecal, blowhole, and/or gastric samples at both sites, including methicillin-resistant Staphylococcus aureus (MRSA) at CHS. Collectively, these studies illustrate the importance of long-term surveillance of estuarine populations of bottlenose dolphins and reaffirm their important role as sentinels for marine ecosystems and public health.


Asunto(s)
Delfín Mular , Monitoreo del Ambiente , Animales , Medición de Riesgo , Sudeste de Estados Unidos/epidemiología
9.
Emerg Infect Dis ; 22(12): 2063-2069, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27869614

RESUMEN

Cutaneous granulomas in dolphins were believed to be caused by Lacazia loboi, which also causes a similar disease in humans. This hypothesis was recently challenged by reports that fungal DNA sequences from dolphins grouped this pathogen with Paracoccidioides brasiliensis. We conducted phylogenetic analysis of fungi from 6 bottlenose dolphins (Tursiops truncatus) with cutaneous granulomas and chains of yeast cells in infected tissues. Kex gene sequences of P. brasiliensis from dolphins showed 100% homology with sequences from cultivated P. brasiliensis, 73% with those of L. loboi, and 93% with those of P. lutzii. Parsimony analysis placed DNA sequences from dolphins within a cluster with human P. brasiliensis strains. This cluster was the sister taxon to P. lutzii and L. loboi. Our molecular data support previous findings and suggest that a novel uncultivated strain of P. brasiliensis restricted to cutaneous lesions in dolphins is probably the cause of lacaziosis/lobomycosis, herein referred to as paracoccidioidomycosis ceti.


Asunto(s)
Enfermedades de los Animales/microbiología , Dermatomicosis/veterinaria , Delfines , Granuloma/veterinaria , Paracoccidioides , Paracoccidioidomicosis/veterinaria , Enfermedades de los Animales/patología , Animales , Secuencia de Bases , Biopsia , ADN de Hongos , Paracoccidioides/clasificación , Paracoccidioides/genética , Paracoccidioides/aislamiento & purificación , Filogenia
10.
Med Mycol ; 54(6): 659-65, 2016 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-27118803

RESUMEN

Lobomycosis (lacaziosis) is a chronic, granulomatous, fungal infection of the skin and subcutaneous tissues of humans and dolphins. To date, the causative agent, the yeast-like organism Lacazia loboi, has not been grown in the laboratory, and there have been no recent reports describing attempts to culture the organism. As a result, studies on the efficacy of therapeutics and potential environmental reservoirs have not been conducted. Therefore, the objective of the current study was to utilize both classical and novel microbiological methods in order to stimulate growth of Lacazia cells collected from dolphin lesions. This included the experimental inoculation of novel media, cell culture, and the use of artificial skin matrices. Although unsuccessful, the methods and results of this study provide important insight into new approaches that could be utilized in future investigations of this elusive organism.


Asunto(s)
Delfín Mular/microbiología , Lacazia/crecimiento & desarrollo , Lacazia/aislamiento & purificación , Lobomicosis/veterinaria , Técnicas Microbiológicas/métodos , Animales , Océano Atlántico , Granuloma/patología , Histocitoquímica , Lobomicosis/microbiología , Lobomicosis/patología , Microscopía
11.
Dis Aquat Organ ; 115(3): 175-84, 2015 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-26290502

RESUMEN

Mucocutaneous lesions were biopsied from free-ranging Atlantic bottlenose dolphins Tursiops truncatus inhabiting the Indian River Lagoon (IRL), Florida, and estuarine waters of Charleston (CHS), South Carolina, USA, between 2003 and 2013. A total of 78 incisional biopsies from 58 dolphins (n=43 IRL, n=15 CHS) were examined. Thirteen dolphins had 2 lesions biopsied at the same examination, and 6 dolphins were re-examined and re-biopsied at time intervals varying from 1 to 8 yr. Biopsy sites included the skin (n=47), tongue (n=2), and genital mucosa (n=29). Pathologic diagnoses were: orogenital sessile papilloma (39.7%), cutaneous lobomycosis (16.7%), tattoo skin disease (TSD; 15.4%), nonspecific chronic to chronic-active dermatitis (15.4%), and epidermal hyperplasia (12.8%). Pathologic diagnoses from dolphins with 2 lesions were predominately orogenital sessile papillomas (n=9) with nonspecific chronic to chronic-active dermatitis (n=4), TSD (n=3), lobomycosis (n=1), and epidermal hyperplasia (n=1). Persistent pathologic diagnoses from the same dolphins re-examined and re-biopsied at different times included genital sessile papillomas (n=3), lobomycosis (n=2), and nonspecific dermatitis (n=2). This is the first study documenting the various types, combined prevalence, and progression of mucocutaneous lesions in dolphins from the southeastern USA. The data support other published findings describing the health patterns in dolphins from these geographic regions. Potential health impacts related to the observed suite of lesions are important for the IRL and CHS dolphin populations, since previous studies have indicated that both populations are affected by complex infectious diseases often associated with immunologic disturbances and anthropogenic contaminants.


Asunto(s)
Delfín Mular , Enfermedades de la Boca/veterinaria , Membrana Mucosa/patología , Enfermedades de la Piel/veterinaria , Animales , Océano Atlántico , Biopsia , Femenino , Florida/epidemiología , Genitales Femeninos/patología , Genitales Masculinos/patología , Masculino , Enfermedades de la Boca/epidemiología , Enfermedades de la Boca/patología , Papiloma/patología , Papiloma/veterinaria , Enfermedades de la Piel/epidemiología , Enfermedades de la Piel/patología
12.
Gen Comp Endocrinol ; 206: 203-12, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-25019655

RESUMEN

There is a growing concern about the impacts of stress in marine mammals as they face a greater array of threats. The stress response of free-ranging dolphins (Tursiops truncatus) was examined by measuring their physiologic response to capture and handling. Samples were collected from 168 dolphins during capture-release health assessments 2003-2007 at two study sites: Charleston, SC (CHS) and the Indian River Lagoon, FL (IRL). Adrenocorticotropic hormone (ACTH), cortisol, aldosterone (ALD) and catecholamines (epinephrine (EPI), norepinephrine (NOR), dopamine (DA)), were measured in blood and cortisol in urine. Mean time to collect pre-examination samples after netting the animals was 22min; post-examination samples were taken prior to release (mean 1h 37min). EPI and DA concentrations decreased significantly with increased time to blood sampling. ACTH and cortisol levels increased from the initial capture event to the post-examination sample. EPI concentrations increased significantly with increasing time to the pre-examination sample and decreased significantly with time between the pre- and post-examination sample. Cortisol concentrations increased between the pre- and post-examination in CHS dolphins. Age- and sex-adjusted mean pre-examination values of catecholamines were significantly higher in CHS dolphins; ALD was higher in IRL dolphins. Significant differences related to age or sex included higher NOR concentrations in males; higher ALD and urine cortisol levels in juveniles than adults. Wild dolphins exhibited a typical mammalian response to acute stress of capture and restraint. Further studies that relate hormone levels to biological and health endpoints are warranted.


Asunto(s)
Delfín Mular/fisiología , Hormonas/sangre , Hidrocortisona/orina , Estrés Fisiológico , Animales , Femenino , Masculino
13.
Dis Aquat Organ ; 108(1): 71-81, 2014 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-24492056

RESUMEN

Sera from free-ranging Atlantic bottlenose dolphins Tursiops truncatus inhabiting the Indian River Lagoon (IRL), Florida, and coastal waters of Charleston (CHS), South Carolina, USA, were tested for antibodies to Chlamydiaceae as part of a multidisciplinary study of individual and population health. A suite of clinicoimmunopathologic variables was evaluated in Chlamydiaceae-seropositive dolphins (n = 43) and seronegative healthy dolphins (n = 83). Fibrinogen, lactate dehydrogenase, amylase, and absolute numbers of neutrophils, lymphocytes, and basophils were significantly higher, and serum bicarbonate, total alpha globulin, and alpha-2 globulin were significantly lower in dolphins with positive Chlamydiaceae titers compared with seronegative healthy dolphins. Several differences in markers of innate and adaptive immunity were also found. Concanavalin A-induced T lymphocyte proliferation, lipopolysaccharide-induced B lymphocyte proliferation, and granulocytic phagocytosis were significantly lower, and absolute numbers of mature CD 21 B lymphocytes, natural killer cell activity and lysozyme concentration were significantly higher in dolphins with positive Chlamydiaceae antibody titers compared to seronegative healthy dolphins. Additionally, dolphins with positive Chlamydiaceae antibody titers had significant increases in ELISA antibody titers to Erysipelothrix rhusiopathiae. These data suggest that Chlamydiaceae infection may produce subclinical clinicoimmunopathologic perturbations that impact health. Any potential subclinical health impacts are important for the IRL and CHS dolphin populations, as past studies have indicated that both dolphin populations are affected by other complex infectious and neoplastic diseases, often associated with immunologic perturbations and anthropogenic contaminants.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Delfín Mular , Infecciones por Chlamydiaceae/veterinaria , Chlamydiaceae/inmunología , Animales , Infecciones por Chlamydiaceae/sangre , Infecciones por Chlamydiaceae/inmunología , Femenino , Masculino
14.
J R Soc Interface ; 21(217): 20230755, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39163031

RESUMEN

Natural biological branching processes can form tree-like structures at all scales and, moreover, can perform various functions to achieve specific goals; these include receiving stimuli, performing two-way communication along their branches, and dynamically reforming (extending or retracting branches). They underlie many biological systems with considerable diversity, frequency, and geometric complexity; these include networks of neurons, organ tissue, mycorrhizal fungal networks, plant growth, foraging networks, etc. This paper presents a biomimetic DNA tile assembly model (Y-STAM) to implement dynamic branching processes. The Y-STAM is a relatively compact mathematical model providing a design space where complex, biomimetic branch-like growth and behaviour can emerge from the appropriate parametrization of the model. We also introduce a class of augmented models (Y-STAM+) that provide time- and space-dependent modulations of tile glue strengths, which enable further diverse behaviours that are not possible in the Y-STAM; these additional behaviours include refinement of network assemblies, obstacle avoidance, and programmable growth patterns. We perform and discuss extensive simulations of the Y-STAM and the Y-STAM+. We envision that these models could be applied at the mesoscale and the molecular scale to dynamically assemble branching DNA nanostructures and offer insights into complex biological self-assembly processes.


Asunto(s)
Modelos Biológicos , Biomimética/métodos , ADN/metabolismo , ADN/química , Simulación por Computador
15.
Nanoscale ; 15(17): 7676-7694, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37066980

RESUMEN

DNA computing has emerged as a promising alternative to achieve programmable behaviors in chemistry by repurposing the nucleic acid molecules into chemical hardware upon which synthetic chemical programs can be executed. These chemical programs are capable of simulating diverse behaviors, including boolean logic computation, oscillations, and nanorobotics. Chemical environments such as the cell are marked by uncertainty and are prone to random fluctuations. For this reason, potential DNA-based molecular devices that aim to be deployed into such environments should be capable of adapting to the stochasticity inherent in them. In keeping with this goal, a new subfield has emerged within DNA computing, focusing on developing approaches that embed learning and inference into chemical reaction systems. If realized in biochemical contexts, such molecular machines can engender novel applications in fields such as biotechnology, synthetic biology, and medicine. Therefore, it would be beneficial to review how different ideas were conceived, how the progress has been so far, and what the emerging ideas are in this nascent field of 'molecular-scale learning'.


Asunto(s)
Computadores Moleculares , Ácidos Nucleicos , ADN/química , Lógica , Biología Sintética
16.
Harmful Algae ; 129: 102526, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37951612

RESUMEN

This investigation was undertaken to characterize health effects associated with a major bloom of blue-green algae due to the proliferation Microcystis aeruginosa that occurred in Florida in 2018. Cyanobacteria produce multiple toxins, including the potent hepatotoxic microcystins (MCs), that have been reported to cause illness in exposed persons worldwide. Widespread exposure to toxins released by blue-green algae during the 2018 bloom was shown by the presence of MCs in the nasal passages of 95 percent of the individuals studied previously in south Florida (Schaefer et al., 2020). The current analyses were conducted to determine whether self-reported symptoms were associated with activity patterns, direct contact with water, residential, recreational, and occupational exposure. The 125 persons who participated in the initial study reported an average of 4.94 (± 4.87) symptoms. Those reported most commonly included rhinorrhea, sneezing, headache, sore throat and dry cough. Respiratory symptoms were reported by 74%, ocular symptoms by 62%, and gastrointestinal symptoms by 35% of respondents. Residential and recreational exposures were associated with increased risks of respiratory, gastrointestinal, or ocular symptoms in univariate and adjusted multivariable analyses. Residential exposure was significantly associated with increased reporting of dry cough (p = 0.03), dyspnea (p < 0.01) and wheezy respirations (p = 0.04). Among persons reporting gastrointestinal symptoms, nausea (p = 0.02) and abdominal pain (p < 0.01) were significantly associated with residential exposure. Recreational exposure was significantly associated with sore throat and eye irritation. The findings add to the evidence that exposure to cyanobacteria at concentrations encountered during an algal bloom is associated with a diverse array of symptoms and that inhalation of aerosols constitutes an important exposure pathway.


Asunto(s)
Cianobacterias , Faringitis , Humanos , Florida , Tos , Floraciones de Algas Nocivas
17.
Avian Dis ; 56(2): 263-71, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22856180

RESUMEN

Backyard gallinaceous bird flocks may play an important role in the spread of infectious diseases within poultry populations as well as the transmission of zoonotic diseases to humans. An epidemiologic characterization was conducted of Colorado backyard flocks to gather information on general flock characteristics, human movement of birds, human-bird interaction, biosecurity practices, and flock health. Our results suggest that backyard poultry flocks in Colorado are small-sized flocks (68.6% of flocks had < 50 birds); consist primarily of layer chickens (85.49% of flocks), show chickens (32.18% of flocks), and waterfowl (34.07% of flocks); and are primarily owned for food (meat or egg) production for the family (86.44%) or as pet or hobby birds (42.27%). The backyard flock environment may promote bird-to-bird transmission as well as bird-to-human transmission of infectious disease. Birds are primarily housed with free access to the outside (96.85%), and many are moved from the home premises (46.06% within 1 yr). Human contact with backyard flocks is high, biosecurity practices are minimal, and bird health is negatively impacted by increased movement events. Increased knowledge of backyard bird characteristics and associated management practices can provide guidelines for the development of measures to decrease disease transmission between bird populations, decrease disease transmission from birds to humans, and increase the overall health of backyard birds.


Asunto(s)
Anseriformes , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/transmisión , Columbidae , Galliformes , Animales , Enfermedades de las Aves/clasificación , Enfermedades de las Aves/prevención & control , Distribución de Chi-Cuadrado , Colorado/epidemiología , Estudios Transversales , Encuestas Epidemiológicas , Vivienda para Animales , Oportunidad Relativa , Densidad de Población , Enfermedades de las Aves de Corral/clasificación , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/transmisión , Encuestas y Cuestionarios
18.
Dis Aquat Organ ; 101(2): 139-44, 2012 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-23135141

RESUMEN

Necropsies were conducted on 4 Antillean manatees Trichechus manatus manatus that were stranded in single events on the coastal beaches of Puerto Rico from August 2010 to August 2011. Three manatees were emaciated and the gastrointestinal tracts were devoid of digesta. Microscopically, all manatees had severe widespread inflammatory lesions of the gastrointestinal tract and heart with intralesional tachyzoites consistent with Toxoplasma gondii identified by histological, ultrastructural and immunohistochemical techniques. The gastrointestinal lesions included severe, multifocal to diffuse, chronic-active enteritis, colitis and/or gastritis often with associated ulceration, necrosis and hemorrhage. Enteric leiomyositis was severe and locally extensive in all cases and associated with the most frequently observed intralesional protozoans. Moderate to severe, multifocal, chronic to chronic-active, necrotizing myocarditis was also present in all cases. Additionally, less consistent inflammatory lesions occurred in the liver, lung and a mesenteric lymph node and were associated with fewer tachyzoites. Sera (n = 30) collected from free-ranging and captive Puerto Rican manatees and a rehabilitated/released Puerto Rican manatee from 2003 to 2012 were tested for antibodies for T. gondii. A positive T. gondii antibody titer was found in 2004 in 1 (3%) of the free-ranging cases tested. Disease caused by T. gondii is rare in manatees. This is the first report of toxoplasmosis in Antillean manatees from Puerto Rico. Additionally, these are the first reported cases of disseminated toxoplasmosis in any sirenian. The documentation of 4 cases of toxoplasmosis within one year and the extremely low seroprevalence to T. gondii suggest that toxoplasmosis may be an emerging disease in Antillean manatees from Puerto Rico.


Asunto(s)
Toxoplasmosis Animal/patología , Trichechus manatus , Animales , Anticuerpos Antiprotozoarios , Resultado Fatal , Femenino , Masculino , Puerto Rico/epidemiología , Toxoplasmosis Animal/epidemiología
19.
J Zoo Wildl Med ; 43(4): 730-8, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23272338

RESUMEN

As part of the Bottlenose Dolphin Health and Risk Assessment study, blood, gastric, fecal, and blowhole samples were collected from 114 Atlantic bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon, Florida (IRL), and from 73 dolphins from the estuarine waters around Charleston, South Carolina (CHS), to assess the presence and degree of cytologic evidence of gastric inflammation from 2003 to 2007. The prevalence of moderate and severe gastric inflammation was 9.6% in the IRL and 11.0% at CHS. A case-control study of 19 dolphins with cytologic evidence of gastric inflammation and 82 with normal cytology from the combined populations was conducted. Blood parameters evaluated included hematology, serum chemistry, serum protein electrophoresis, and stress hormones. Few differences of clinical or statistical significance were found between affected and unaffected dolphins. Serum norepinephrine and cortisol were significantly higher in cases compared to the controls, and aldosterone was marginally higher (P = 0.06) based on eight cases. None of the hematologic, serum chemistry, or serum electrophoresis results were significantly different. Gastric fluid pH was not significantly different between cases and controls. There were no clinically significant aerobic-anaerobic or fungal culture results from gastric contents; bacteria cultured from both groups were considered to represent normal flora. The prevalence of inflammation did not differ by gender. Historically, cytologic evidence of gastric inflammation has constituted a marker of systemic illness in dolphins; however, there was little evidence to indicate systemic illness among affected animals. The data obtained from this study provide a basis for further investigation and evaluation of gastric cytology in wild and managed bottlenose dolphins.


Asunto(s)
Delfín Mular , Técnicas Citológicas/veterinaria , Inflamación/veterinaria , Gastropatías/veterinaria , Animales , Animales Salvajes , Océano Atlántico , Demografía , Femenino , Concentración de Iones de Hidrógeno , Inflamación/patología , Masculino , Gastropatías/patología
20.
Sci Adv ; 8(51): eade4455, 2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36563147

RESUMEN

Improving the precision and function of encapsulating three-dimensional (3D) DNA nanostructures via curved geometries could have transformative impacts on areas such as molecular transport, drug delivery, and nanofabrication. However, the addition of non-rasterized curvature escalates design complexity without algorithmic regularity, and these challenges have limited the ad hoc development and usage of previously unknown shapes. In this work, we develop and automate the application of a set of previously unknown design principles that now includes a multilayer design for closed and curved DNA nanostructures to resolve past obstacles in shape selection, yield, mechanical rigidity, and accessibility. We design, analyze, and experimentally demonstrate a set of diverse 3D curved nanoarchitectures, showing planar asymmetry and examining partial multilayer designs. Our automated design tool implements a combined algorithmic and numerical approximation strategy for scaffold routing and crossover placement, which may enable wider applications of general DNA nanostructure design for nonregular or oblique shapes.

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