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1.
Environ Sci Process Impacts ; 26(5): 928-941, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38635247

RESUMEN

Motor vehicles are among the major sources of pollutants and greenhouse gases in urban areas and a transition to "zero emission vehicles" is underway worldwide. However, emissions associated with brake and tire wear will remain. We show here that previously unrecognized volatile and semi-volatile organic compounds, which have a similarity to biomass burning emissions are emitted during braking. These include greenhouse gases or, these classified as Hazardous Air Pollutants, as well as nitrogen-containing organics, nitrogen oxides and ammonia. The distribution and reactivity of these gaseous emissions are such that they can react in air to form ozone and other secondary pollutants with adverse health and climate consequences. Some of the compounds may prove to be unique markers of brake emissions. At higher temperatures, nucleation and growth of nanoparticles is also observed. Regions with high traffic, which are often disadvantaged communities, as well as commuters can be impacted by these emissions even after combustion-powered vehicles are phased out.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Emisiones de Vehículos , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Contaminantes Atmosféricos/análisis , Emisiones de Vehículos/análisis , Monitoreo del Ambiente/métodos , Contaminación del Aire/estadística & datos numéricos , Vehículos a Motor
2.
Transl Anim Sci ; 6(4): txac141, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36381952

RESUMEN

The feeding value for ruminants of green hemp biomass, from the low Δ9-tetrahydrocannabinol (Δ9-THC) variety of Cannabis sativa L., is unknown. Twelve Merino ewes were individually penned and randomly allocated on a stratified liveweight basis to one of two pelleted dietary treatments, control (0% hemp, n = 6) or hemp (42% green hemp biomass, n = 6) that delivered a diet meeting the nutrient requirements of the animals. The experimental period consisted of 17 d dietary and housing adaptation, followed by 7 d total urine and feces collection for determination of apparent nutrient digestibility. A ruminal fluid sample was collected on day 27 and assessed for pH, ammonia, volatile fatty acid (VFA), and cannabinoid concentrations. A blood sample from the jugular vein and incisional subcutaneous fat biopsy from an area around the base of the tail were collected on day 28 with additional fat biopsies taken 35 d and 140 d post-feeding to measure cannabinoids. The dry matter (DM), organic matter (OM), and crude protein (CP) digestibilities, along with total VFA concentration did not differ (P = 0.713) between the two diets; however, acid detergent fiber (ADF) and neutral detergent fiber (NDF) digestibilities (P < 0.001), water intake (P = 0.023), and fecal water output (P < 0.001) were significantly lower for the sheep-fed Hemp. Rumen pH did not vary (P = 0.256) between diets, but ruminal ammonia concentration was significantly lower (P = 0.024) for sheep consuming Hemp. Sheep-fed Hemp had significantly greater molar proportions of butyric (P = 0.039) and hexanoic (P = 0.012) acids and lower molar proportions of propionic acid (P = 0.003). There were no differences between diets for N intake (P = 0.175), fecal N output (P = 0.253), and N balance (P = 0.695), with all sheep in positive N balance; however, there was significantly lower (P = 0.001) urinary N output for sheep-fed Hemp. Cannabidiolic acid (CBDA) and tetrahydrocannabinolic acid (THCA) were detected in plasma of all sheep-fed Hemp. ∆9-tetrahydrocannabinol was present in the subcutaneous fat of four of the six sheep on the final day of being fed Hemp, and in all (six) sheep 35 d post-feeding and one sheep 140 d post-feeding Hemp. No cannabinoids were detected in the corresponding samples taken from the sheep-fed Control. Thus, despite green hemp biomass being nutritionally a suitable feed for ruminants, under current Food Standards in Australia, the presence of these cannabinoid residues restricts its use in ruminant diets.

3.
Insect Mol Biol ; 19(4): 473-80, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20408903

RESUMEN

Endoparasitic hymenoptera inject maternal factors into the host, along with their eggs, to subvert the host immune system. The venom protein, Vn50, previously characterized from the wasp Cotesia rubecula inhibits prophenoloxidase activation in its host Pieris rapae and in another lepidopteran, Manduca sexta. We generated a stable line in the model insect, Drosophila melanogaster, which ectopically expresses Vn50. Results indicated that Vn50 expression accelerates larval development, increases oviposition and reduces melanization in the haemolymph of the transgenic flies. Since melanization is known to be an important facet of the insect immune response, we examined the impact of Vn50 expression on susceptibility to pathogens. Transgenic Vn50 flies challenged with the fungus Beauveria bassiana had increased mortality compared with control flies, but there was no significant change in survival in flies challenged with the pathogenic bacteria, Serratia marcescens. Interestingly, mortality induced by the natural pathogen Drosophila C virus was significantly delayed in Vn50 expressing flies. This indicates a wider range of potential hosts that may be affected by Vn50 and its potential for manipulation of immune system in insects.


Asunto(s)
Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/inmunología , Oviposición/fisiología , Parásitos/metabolismo , Venenos de Avispas/metabolismo , Animales , Animales Modificados Genéticamente , Beauveria/fisiología , Drosophila melanogaster/microbiología , Drosophila melanogaster/parasitología , Femenino , Larva/crecimiento & desarrollo , Larva/microbiología , Masculino , Melaninas/biosíntesis , Pupa/crecimiento & desarrollo , Pupa/microbiología , Reproducibilidad de los Resultados , Serratia/fisiología , Análisis de Supervivencia , Transformación Genética
4.
Diabetes Obes Metab ; 11 Suppl 1: 25-30, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19143812

RESUMEN

AIM: The goal of this study was to develop and implement methodology that would aid in the analysis of extended high-density single nucleotide polymorphism (SNP) major histocompatibility complex (MHC) haplotypes combined with human leucocyte antigen (HLA) alleles in relation to type 1 diabetes risk. METHODS: High-density SNP genotype data (2918 SNPs) across the MHC from the Type 1 Diabetes Genetics Consortium (1240 families), in addition to HLA data, were processed into haplotypes using PedCheck and Merlin, and extended DR3 haplotypes were analysed. RESULTS: With this large dense set of SNPs, the conservation of DR3-B8-A1 (8.1) haplotypes spanned the MHC (>/=99% SNP identity). Forty-seven individuals homozygous for the 8.1 haplotype also shared the same homozygous genotype at four 'sentinel' SNPs (rs2157678 'T', rs3130380 'A', rs3094628 'C' and rs3130352 'T'). Conservation extended from HLA-DQB1 to the telomeric end of the SNP panels (3.4 Mb total). In addition, we found that the 8.1 haplotype is associated with lower risk than other DR3 haplotypes by both haplotypic and genotypic analyses [haplotype: p = 0.009, odds ratio (OR) = 0.65; genotype: p = 6.3 x 10(-5), OR = 0.27]. The 8.1 haplotype (from genotypic analyses) is associated with lower risk than the high-risk DR3-B18-A30 haplotype (p = 0.01, OR = 0.23), but the DR3-B18-A30 haplotype did not differ from other non-8.1 DR3 haplotypes relative to diabetes association. CONCLUSION: The 8.1 haplotype demonstrates extreme conservation (>3.4 Mb) and is associated with significantly lower risk for type 1 diabetes than other DR3 haplotypes.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Antígeno HLA-DR3/genética , Polimorfismo de Nucleótido Simple/genética , Secuencia Conservada , Predisposición Genética a la Enfermedad/genética , Genotipo , Haplotipos , Heterocigoto , Homocigoto , Humanos , Linaje , Factores de Riesgo
5.
Phytopathology ; 98(7): 810-4, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18943257

RESUMEN

Fiji leaf gall (FLG) is caused by the Reovirus, Fiji disease virus (FDV), which is transmitted to sugarcane by planthoppers of the genus Perkinsiella. Low vector transmission rates and slow disease symptom development make experimentation within the FDV-Perkinsiella-sugarcane system inherently difficult. A laboratory-based technique was devised to rear the vector using sugarcane leaves as a food source. Planthoppers were reared on sugarcane leaf segments embedded in agarose enclosed within plastic containers. To provide a nondestructive assay for determination of the inoculation potential of planthoppers, FDV was detected by reverse transcription-polymerase chain reaction (RT-PCR) in newly infected sugarcane leaf segments following exposure to viruliferous planthoppers. Leaf segment inoculation correlated with development of FLG symptoms in whole plants that were fed on by the same planthoppers. Analysis of FDV RNAs within the planthopper, measured by quantitative RT-PCR (qRT-PCR), indicated that FDV RNA concentration was associated with successful inoculation of the leaf segment, transmission of FDV to sugarcane and subsequent development of FLG in plants. Quantification of FDV RNA within planthoppers provided an additional measure to assess vector competence in individuals.


Asunto(s)
Hemípteros/virología , Hojas de la Planta/virología , Reoviridae/fisiología , Saccharum/virología , Animales , Hemípteros/fisiología , Insectos Vectores/fisiología , Insectos Vectores/virología , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/virología , Hojas de la Planta/parasitología , ARN Viral/genética , Reoviridae/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Saccharum/parasitología
6.
Rev Esp Anestesiol Reanim ; 64(9): 499-505, 2017 Nov.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28366293

RESUMEN

OBJECTIVE: Octogenarians undergo anatomic and physiopathologic degradation, making airway management problematic, specific to intubation, bag mask ventilation, leading to desaturation and aspiration. Our study's aim was to examine the process of airway management regarding the steps involved in intubation and any deviations or delays in the tasks. MATERIALS AND METHODS: An institutional review board-approved difficult airway prospective observational study in older adults was conducted. Inclusion criteria included airway features indicative of difficult airway, history of failed intubation, the planned use of specialized airway devices, and/or expected airway complications due to comorbidities. Patients 80 years and older were analyzed. Demographic data collected were age, weight, BMI, gender, ASA classification, airway indices, diagnosis, and procedures. Problems with intubation (INT) (≥3 intubation attempts), laborious assisted ventilation (VEN) (2-person and/or application of CPAP>20cmH2O), and complications with oxygenation (OXY) (SpO2<95%) were analyzed. RESULTS: Of the 41 patients enrolled in the study, 3 (7.3%) had all 3: problematic (INT), laborious (VEN), and desaturated (OXY); 8 (19.5%) patients experienced problematic (INT), 20 (48.8%) were described as laborious (VEN), and 14 (34.1%) experienced complications with (OXY). CONCLUSION: In octogenarians, we found a low incidence of difficulty with INT-VEN-OXY together. However, bag mask ventilation was found to be laborious with a high incidence of desaturation. Success rate of INT as a sole metric may not accurately describe the process of the intubation. We recommend alternative airway devices and techniques and the establishment of protocols for airway management in the elderly.


Asunto(s)
Intubación Intratraqueal/métodos , Respiración Artificial/métodos , Anciano de 80 o más Años , Índice de Masa Corporal , Comorbilidad , Femenino , Humanos , Hipoxia/sangre , Hipoxia/etiología , Hipoxia/prevención & control , Intubación Intratraqueal/instrumentación , Máscaras Laríngeas , Masculino , Oxígeno/sangre , Estudios Prospectivos , Respiración Artificial/instrumentación , Índice de Severidad de la Enfermedad
7.
J Leukoc Biol ; 62(5): 588-97, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9365113

RESUMEN

By reverse transcriptase-polymerase chain reaction, enzyme-linked immunosorbent assay, and immunohistochemistry, MGSA-alpha, -beta, -gamma, and CXCR2 mRNA expression and proteins are detected in 7 out of 10 human melanoma lesions. The biological consequence of constitutive expression of the MGSA/GRO chemokine in immortalized melanocytes was tested in SCID and nude mouse models. Continuous expression of MGSA/GRO-alpha, -beta, or -gamma in immortalized melan-a mouse melanocytes results in nearly 100% tumor formation for each of the clones tested, whereas clones expressing only the neomycin resistance vector form tumors <10% of the time. Moreover, antibodies to the MGSA/GRO proteins slow or inhibit the formation of tumors in the SCID mouse model and block the angiogenic response to conditioned medium from the tumor-producing clones. Transcription of the MGSA/GRO chemokines is regulated by an enhancesome-like complex comprised of the nuclear factor-kappaB (NF-kappaB), HMG(I)Y, IUR, and Sp1 elements. In Hs294T melanoma cells the half life of the IKB protein is shortened in comparison to normal retinal epithelial cells, facilitating the endogenous nuclear localization of NF-kappaB. We propose that this endogenous nuclear NF-kappaB, working in concert with the 115-kDa IUR-binding factor, promotes constitutive expression of MGSA/GRO genes.


Asunto(s)
Quimiocinas CXC , Quimiocinas/biosíntesis , Factores Quimiotácticos/biosíntesis , Sustancias de Crecimiento/biosíntesis , Péptidos y Proteínas de Señalización Intercelular , Melanoma/metabolismo , Melanoma/patología , Animales , Quimiocina CXCL1 , Progresión de la Enfermedad , Humanos , Ratones
8.
Arch Ophthalmol ; 96(9): 1583-91, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-99132

RESUMEN

Choroidal malignant melanomas in nine patients were treated with proton beam irradiation at the Harvard Cyclotron Laboratory, Cambridge, Mass. Each patient received five proton beam treatments in eight to ten days, totalling 4,730 to 8,570 rads at the tumor. No complications occurred during the treatment or follow-up period, which, at the time of this writing, ranges from one to 24 months, with an average of 12 months. No further growth of the tumor has been observed in any patient. Different signs of tumor regression have been noted. Resolution of the serous retinal detachments that accompanied some tumors is the earliest finding. Pigment changes over the surface of the tumor and adjacent pigment epithelium is a usual initial tumor response. Fluorescein angiography initially showed decreased leakage of dye; later, destruction of the tumor's vasculature and elimination of fluorescein leakage became evident. Only large choroidal vessels remained patient. Ultrasonography revealed decreased height of the tumors postirradiation, and the radioactive phosphorus (32P) uptake test, repeated in one patient, turned negative on postirradiation measurements.


Asunto(s)
Neoplasias de la Coroides/radioterapia , Melanoma/radioterapia , Radioterapia de Alta Energía/métodos , Anciano , Neoplasias de la Coroides/mortalidad , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Melanoma/mortalidad , Persona de Mediana Edad , Aceleradores de Partículas , Pronóstico , Dosis de Radiación , Televisión
9.
Br J Ophthalmol ; 68(7): 479-85, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6329261

RESUMEN

Proton beam irradiation has been used for the treatment of 60 eyes with choroidal melanomas located 3 mm or less from the fovea. The average follow-up period was 18 months. 86% of the treated lesions showed regression at the time of this analysis, and the 14% that did not were followed up for less than a year. Visual acuity remained the same in 47% of the treated eyes, improved in 20%, and deteriorated in 33%. 58% of the treated eyes had visual acuity of 20/100 or better at the last follow-up examination. Radiation vasculopathy with macular oedema was the most common complication, and it was observed in 22% of the treated eyes. These preliminary observations suggest that proton beam irradiation may be a reasonable alternative to enucleation even for this group of choroidal melanomas, which is considered unfavourable in respect of the preservation of visual function.


Asunto(s)
Neoplasias de la Coroides/radioterapia , Melanoma/radioterapia , Protones , Agudeza Visual , Adolescente , Adulto , Anciano , Femenino , Angiografía con Fluoresceína , Fóvea Central , Humanos , Mácula Lútea/efectos de la radiación , Masculino , Persona de Mediana Edad
10.
Br J Ophthalmol ; 63(2): 135-9, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-106873

RESUMEN

This is our first case of malignant melanoma of the ciliary body treated with proton beam irradiation, a technique that we developed for irradiating choroidal melanomas. After 21 months of follow-up no growth of the tumour has been observed, and shrinkage of the tumour was noted on the follow-up photographs and by ultrasonography. The 32P uptake test, which was positive before treatment, turned negative 14 months after irradiation. The described technique of proton beam irradiation might offer an alternative for the treatment of ciliary body melanomas when the present techniques of iridocyclectomy cannot be applied because of the size of the lesion.


Asunto(s)
Cuerpo Ciliar , Neoplasias del Ojo/radioterapia , Melanoma/radioterapia , Femenino , Humanos , Persona de Mediana Edad , Protones , Dosificación Radioterapéutica , Radioterapia de Alta Energía
11.
J Pers Soc Psychol ; 47(1): 105-14, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6747812

RESUMEN

We completed a comprehensive factor analysis of the full MMPI item pool by using recent advances in computational facilities. Nearly 20,000 MMPI protocols were collected for the analysis, however, we discarded invalid records and protocols with more than 50 missing items. Analyses were computed on a developmental sample of 5,506 subjects and a cross-validation sample of 5,632. Twenty-one replicated factors were found by using an orthogonal varimax solution. The rotated factors were submitted to several experts on MMPI for factor naming. The consensus obtained on the item factors suggests that this analysis provides an unambiguous picture of the major content dimensions in the MMPI item pool.


Asunto(s)
MMPI , Trastornos Mentales/diagnóstico , Adolescente , Adulto , Anciano , Servicios Comunitarios de Salud Mental , Femenino , Humanos , Masculino , Trastornos Mentales/psicología , Persona de Mediana Edad , Psicometría
12.
J Pediatr Surg ; 49(8): 1259-63, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25092086

RESUMEN

BACKGROUND: Minimally invasive repair of pectus excavatum has become an established method for repair of pectus excavatum. Bar displacement or rotation remains the most common complication of this repair requiring return to the operating room. METHODS: Retrospective review of all patients at a single institution who underwent repair of pectus excavatum using FiberWire for bar stabilization between December 2009 and March 2013 was undertaken. RESULTS: 93 patients underwent minimally invasive pectus repair using FiberWire during the study period. The patients included 73 males and 20 females, with an average age of 14.6years (range 7-21years). Mean operative time was 102minutes (range 56-198minutes). No patients developed wound complications, two patients developed pain because of bar migration and required return to the OR, and no patients had recurrence of their pectus defect because of bar migration during the study period. Median length of follow-up was 17months (range 3-36months). CONCLUSION: Stabilization of pectus bars using circumferential rib fixation with FiberWire at multiple points on both sides of the bar appears to be effective in preventing bar rotation and displacement, and requires minimal change to the operation as it has been previously described. Early experience shows a low rate of complications.


Asunto(s)
Placas Óseas , Hilos Ortopédicos , Tórax en Embudo/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos , Costillas/cirugía , Técnicas de Sutura/instrumentación , Toracoplastia/métodos , Adolescente , Niño , Femenino , Estudios de Seguimiento , Tórax en Embudo/diagnóstico por imagen , Humanos , Masculino , Radiografía Torácica , Estudios Retrospectivos , Costillas/diagnóstico por imagen , Resultado del Tratamiento , Adulto Joven
13.
Cell Death Dis ; 1: e74, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21151771

RESUMEN

The transcription factor p63 is required for proper epidermal barrier formation and maintenance. Herein, we used chromatin immunoprecipitation coupled with DNA sequencing to identify novel p63 target genes involved in normal human epidermal keratinocyte (NHEKs) growth and differentiation. We identified over 2000 genomic sites bound by p63, of which 82 were also transcriptionally regulated by p63 in NHEKs. Through the discovery of interleukin-1-α as a p63 target gene, we identified that p63 is a regulator of epithelial-mesenchymal crosstalk. Further, three-dimensional organotypic co-cultures revealed TCF7L1, another novel p63 target gene, as a regulator of epidermal proliferation and differentiation, providing a mechanism by which p63 maintains the proliferative potential of basal epidermal cells. The discovery of new target genes links p63 to diverse signaling pathways required for epidermal development, including regulation of paracrine signaling to proliferative potential. Further mechanistic insight into p63 regulation of epidermal cell growth and differentiation is provided by the identification of a number of novel p63 target genes in this study.


Asunto(s)
Queratinocitos/metabolismo , Comunicación Paracrina , Transactivadores/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Sitios de Unión , Diferenciación Celular , Línea Celular , Inmunoprecipitación de Cromatina , Regulación de la Expresión Génica , Humanos , Interleucina-1alfa/genética , Interleucina-1alfa/metabolismo , Queratinocitos/citología , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Transactivadores/genética , Proteína 1 Similar al Factor de Transcripción 7/genética , Proteína 1 Similar al Factor de Transcripción 7/metabolismo , Factores de Transcripción , Proteínas Supresoras de Tumor/genética
15.
J Virol ; 75(24): 12220-7, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11711613

RESUMEN

Pariacoto virus (PaV) is a nodavirus that was recently isolated in Peru from the Southern armyworm, Spodoptera eridania. Virus particles are non enveloped and about 30 nm in diameter and have T=3 icosahedral symmetry. The 3.0-A crystal structure shows that about 35% of the genomic RNA is icosahedrally ordered, with the RNA forming a dodecahedral cage of 25-nucleotide (nt) duplexes that underlie the inner surface of the capsid. The PaV genome comprises two single-stranded, positive-sense RNAs: RNA1 (3,011 nt), which encodes the 108-kDa catalytic subunit of the RNA-dependent RNA polymerase, and RNA2 (1,311 nt), which encodes the 43-kDa capsid protein precursor alpha. In order to apply molecular genetics to the structure and assembly of PaV, we identified susceptible cell lines and developed a reverse genetic system for this virus. Cell lines that were susceptible to infection by PaV included those from Spodoptera exigua, Helicoverpa zea and Aedes albopictus, whereas cells from Drosophila melanogaster and Spodoptera frugiperda were refractory to infection. To recover virus from molecular clones, full-length cDNAs of PaV RNAs 1 and 2 were cotranscribed by T7 RNA polymerase in baby hamster kidney cells that expressed T7 RNA polymerase. Lysates of these cells were infectious both for cultured cells from Helicoverpa zea (corn earworm) and for larvae of Galleria mellonella (greater wax moth). The combination of infectious cDNA clones, cell culture infectivity, and the ability to produce milligram amounts of virus allows the application of DNA-based genetic methods to the study of PaV structure and assembly.


Asunto(s)
ADN Complementario/genética , Nodaviridae/genética , Animales , Línea Celular , Cricetinae , Nodaviridae/crecimiento & desarrollo , Nodaviridae/fisiología , ARN Viral/biosíntesis , Spodoptera , Transcripción Genética , Proteínas Virales/biosíntesis , Ensamble de Virus
16.
Arch Virol ; 141(8): 1509-22, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8856030

RESUMEN

Two new isolates of cricket paralysis virus, TAR and SIM, are described that were originally isolated from laboratory colonies of Drosophila melanogaster and Drosophila simulans respectively. Using a combination of biological, serological and molecular characters it was possible to distinguish the SIM isolate from all other isolates and it is thus described as a new strain; CrPVSIM. The TAR isolate however, was indistinguishable from the CrPV reference isolate CrPVVIC/GM/D2(2)/Gm/D2(2) (Teleogryllus commodus, Victoria, Australia, 1968). The molecular characters used in the present study were obtained by combining PCR and restriction endonuclease digestion of the amplified fragments. This work demonstrates that such molecular characters, when used in combination with others, provide a powerful set of taxonomic characters for classifying CrPV isolates and strains and assessing their genetic relatedness.


Asunto(s)
Drosophila/virología , Gryllidae/virología , Virus de Insectos/clasificación , Picornaviridae/clasificación , Aedes/citología , Animales , Australia , Abejas , Línea Celular , Drosophila melanogaster/virología , Virus de Insectos/genética , Virus de Insectos/inmunología , Virus de Insectos/aislamiento & purificación , Mariposas Nocturnas/citología , Hibridación de Ácido Nucleico , Filogenia , Picornaviridae/genética , Picornaviridae/inmunología , Picornaviridae/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Conejos , Mapeo Restrictivo , Spodoptera/citología
17.
J Gen Virol ; 79 ( Pt 1): 191-203, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9460942

RESUMEN

The complete nucleotide sequence of the genomic RNA from the insect picorna-like virus Drosophila C virus (DCV) was determined. The DCV sequence predicts a genome organization different to that of other RNA virus families whose sequences are known. The single-stranded positive-sense genomic RNA is 9264 nucleotides in length and contains two large open reading frames (ORFs) which are separated by 191 nucleotides. The 5' ORF contains regions of similarities with the RNA-dependent RNA polymerase, helicase and protease domains of viruses from the picornavirus, comovirus and sequivirus families. The 3' ORF encodes the capsid proteins as confirmed by N-terminal sequence analysis of these proteins. The capsid protein coding region is unusual in two ways: firstly the cistron appears to lack an initiating methionine and secondly no subgenomic RNA is produced, suggesting that the proteins may be translated through internal initiation of translation from the genomic length RNA. The finding of this novel genome organization for DCV shows that this virus is not a member of the Picornaviridae as previously thought, but belongs to a distinct and hitherto unrecognized virus family.


Asunto(s)
Drosophila melanogaster/virología , Genoma Viral , Virus de Insectos/genética , Picornaviridae/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Cápside/genética , Secuencia Conservada , ADN Complementario , Virus de Insectos/clasificación , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Picornaviridae/clasificación , ARN Viral , Homología de Secuencia de Aminoácido
18.
J Invertebr Pathol ; 73(3): 248-54, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10222177

RESUMEN

Reverse transcription coupled with polymerase chain reaction and restriction enzyme analysis was used to characterize 12 Drosophila C virus isolates from geographically different regions. A 1.2-kb fragment was amplified from cDNA and profiles from digestion with 20 restriction enzymes were generated. Analysis of the restriction fragment data gave estimates of nucleotide divergence of 0-10% between isolates. The isolates were grouped on the basis of genetic distance estimates derived from the restriction data. For the isolates from which a single genotype could be purified, a geographical pattern in the distribution of viral genotypes was identified. The 4 Moroccan isolates were very closely related to each other, differing in only 1 restriction profile. The 2 Australian isolates were each other's closest relatives, as were the 2 isolates first recovered in France. The PCR-RFLP technique used in this study has provided us with a simple procedure which can be used to characterize DCV isolates. A single enzyme, Taq I, generated 5 distinct and diagnostic restriction fragment patterns, which allowed easy assignment of isolates to one of the five viral genotypes identified in this study.


Asunto(s)
Virus de Insectos/genética , Picornaviridae/genética , Animales , Drosophila melanogaster/virología , Virus de Insectos/clasificación , Virus de Insectos/aislamiento & purificación , Picornaviridae/clasificación , Picornaviridae/aislamiento & purificación , Polimorfismo de Longitud del Fragmento de Restricción , Mapeo Restrictivo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
Med Care ; 14(5 Suppl): 213-22, 1976 May.
Artículo en Inglés | MEDLINE | ID: mdl-933575

RESUMEN

The long-term care project of the Iowa Hospital Association has demonstrated the feasibility and utility of a multipurpose data system for nursing homes and related institutions. Important features of the Iowa system are emphasis on the needs and constraints of those providing care and collecting the data; prior establishment of specific criteria for the content of the system; the use of three related forms (admission, evaluation, and discharge) to produce current reports; and ease, flexibility, and transferability. A significant byproduct of the demonstration project was improved record keeping and patient care planning by the 14 participating facilities. Major problems encountered were lack of experience on the part of nursing homes and external regulatory agencies in defining their data needs and using data effectively, and financial support. Contribution to cost by external agencies in return for data and a major commitment to educational programs, both initial and continuing, are seen as essential to the success of long-term care data systems.


Asunto(s)
Sistemas de Información , Casas de Salud , Empleos en Salud/educación , Iowa , Registros Médicos , Planificación de Atención al Paciente , Estadística como Asunto
20.
Virology ; 208(1): 84-98, 1995 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11831734

RESUMEN

In this paper we report the complete nucleotide sequence of the larger segment (5312 nucleotides) of the bipartite RNA genome of Helicoverpa armigera stunt tetravirus (HaSV). HaSV therefore becomes the first member of the Tetraviridae, a virus family with a host range restricted to lepidopteran insects, whose genome has been completely sequenced. HaSV RNA 1 encodes a 187K protein which includes three domains conserved in RNA-dependent RNA polymerases of RNA viruses in the alpha-like superfamily. Analysis of the replicase sequence confirms the status of the Tetraviridae as a distinct family within this superfamily, which includes animal, plant, and insect viruses, and shows the least-distantly related replicase for all three domains to be that of the hepatitis E virus. Another feature of the nonpolyadenylated HaSV genomic RNAs is a well-conserved 3'-terminal tRNA-like structure, the first such structure discerned in an animal virus. However, in contrast to the tRNA-like structures on some plant virus RNAs, the HaSV structure, which has a valine anticodon (CAU), appears to form without a pseudoknot and therefore resembles authentic tRNA(Val) more closely than do the plant viral structures. The implications of these observations for our understanding of RNA virus evolution are discussed.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/genética , Virus de Insectos/genética , Lepidópteros/virología , ARN Viral/genética , Regiones no Traducidas 3' , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario/análisis , ADN Complementario/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Genoma Viral , Datos de Secuencia Molecular , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Alineación de Secuencia
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