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1.
Heliyon ; 9(9): e20198, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809521

RESUMEN

Curbing the worst impacts of global climate change will require rapidly transitioning away from fossil fuel across all sectors of the economy. This transition will also yield substantial co-benefits, as fossil fuel combustion releases harmful pollutants into the air. In this article, we present an analysis of the co-benefits to health and health-care costs related from decarbonization of the power sector, using the Virginia Clean Economy Act (VCEA) as a case study. Using a model that combines a source-response matrix approach to pollutant concentration modelling tied to health impact functions, our analysis shows that, by 2045, the VCEA will save up to 32 lives per year across the state, and avoid up to $355 million per year in health-related costs. Fossil-fuel free generation will also help the most disadvantaged communities, as counties in the highest poverty rate quintile also avoid the most pollutant-related deaths.

2.
Sci Adv ; 8(14): eabk1261, 2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35385315

RESUMEN

The climate history of the Sahara desert during recent millennia is obscured by the near absence of natural climate archives, hampering insight in the relative importance of southerly (tropical) and northerly (midlatitude) weather systems at submillennial time scales. A new lake sediment record from Ounianga Serir oasis in northern Chad, spanning the Late Holocene without interruption, confirms that immediately before ca 4200 years ago, the Sahara experienced an episode of hyperaridity even more extreme than today's desert climate. The hypersaline terminal lake which formed afterwards never desiccated during the late Holocene due to continuous inflow of fossil groundwater, yet its water balance was sensitive to temporal variation in local rainfall and lake surface evaporation. Our in-lake geochemical proxies show that, during the last 3000 years, century-scale hydroclimate variation in the central Sahara primarily tracked the intensity of the tropical West African monsoon, modulated at shorter time scales by weather patterns linked to shifts in midlatitude Atlantic Ocean circulation.

3.
Protein Pept Lett ; 28(4): 388-402, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32798369

RESUMEN

BACKGROUND: Antimicrobial Peptides (AMPs) are an attractive alternative to traditional small molecule antibiotics as AMPs typically target the bacterial cell membrane. A Trp-rich peptide sequence derived from water buffalo (Bubalus bubalis), BuCATHL4B was previously identified as a broad-spectrum antimicrobial peptide. OBJECTIVE: In this work, native Trp residues were replaced with other naturally occurring aromatic amino acids to begin to elucidate the importance of these residues on peptide activity. METHODS: Minimal Inhibitory Concentration (MIC) results demonstrated activity against seven strains of bacteria. Membrane and bilayer permeabilization assays were performed to address the role of bilayer disruption in the activity of the peptides. Lipid vesicle binding and quenching experiments were also performed to gain an understanding of how the peptides interacted with lipid bilayers. RESULTS: MIC results indicate the original, tryptophan-rich sequence, and the phenylalanine substituted sequences exhibit strong inhibition of bacterial growth. In permeabilization assays, peptides with phenylalanine substitutions have higher levels of membrane permeabilization than those substituted with tyrosine. In addition, one of the two-tyrosine substituted sequence, YWY, behaves most differently in the lowest antimicrobial activity, showing no permeabilization of bacterial membranes. Notably the antimicrobial activity is inherently species dependent, with varying levels of activity against different bacteria. CONCLUSION: There appears to be little correlation between membrane permeabilization and activity, indicating these peptides may have additional mechanisms of action beyond membrane disruption. The results also identify two sequences, denoted FFF and YYW, which retain antibacterial activity but have markedly reduced hemolytic activity.


Asunto(s)
Secuencia de Aminoácidos , Péptidos Catiónicos Antimicrobianos , Bacterias/crecimiento & desarrollo , Triptófano/química , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/farmacología , Membrana Dobles de Lípidos/química , Relación Estructura-Actividad
4.
Biochim Biophys Acta Biomembr ; 1861(10): 182984, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31075228

RESUMEN

Antimicrobial peptides (AMPs) have been an area of great interest, due to the high selectivity of these molecules toward bacterial targets over host cells and the limited development of bacterial resistance to these molecules throughout evolution. Previous work showed that when Histidine was incorporated into the peptide C18G it lost antimicrobial activity. The role of pH on activity and biophysical properties of the peptide was investigated to explain this phenomenon. Minimal inhibitory concentration (MIC) results demonstrated that decreased media pH increased antimicrobial activity. Trichloroethanol (TCE) quenching and red-edge excitation spectroscopy (REES) showed a clear pH dependence on peptide aggregation in solution. Trp fluorescence was used to monitor binding to lipid vesicles and demonstrated the peptide binds to anionic bilayers at all pH values tested, however, binding to zwitterionic bilayers was enhanced at pH 7 and 8 (above the His pKa). Dual Quencher Analysis (DQA) confirmed the peptide inserted more deeply in PC:PG and PE:PG membranes, but could insert into PC bilayers at pH conditions above the His pKa. Bacterial membrane permeabilization assays which showed enhanced membrane permeabilization at pH 5 and 6 but vesicle leakage assays indicate enhanced permeabilization of PC and PC:PG bilayers at neutral pH. The results indicate the ionization of the His side chain affects the aggregation state of the peptide in solution and the conformation the peptide adopts when bound to bilayers, but there are likely more subtle influences of lipid composition and properties that impact the ability of the peptide to form pores in membranes.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/uso terapéutico , Permeabilidad de la Membrana Celular/efectos de los fármacos , Secuencia de Aminoácidos , Antibacterianos/metabolismo , Antiinfecciosos/química , Antiinfecciosos/metabolismo , Péptidos Catiónicos Antimicrobianos/metabolismo , Membrana Celular/química , Histidina , Concentración de Iones de Hidrógeno , Membrana Dobles de Lípidos/química , Péptidos/química , Péptidos/uso terapéutico , Fosfatidilcolinas/química , Fosfatidilgliceroles/química , Relación Estructura-Actividad
5.
Sensors (Basel) ; 18(9)2018 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-30223608

RESUMEN

We propose a versatile method for estimating the RMS error of depth data provided by generic 3D sensors with the capability of generating RGB and depth (D) data of the scene, i.e., the ones based on techniques such as structured light, time of flight and stereo. A common checkerboard is used, the corners are detected and two point clouds are created, one with the real coordinates of the pattern corners and one with the corner coordinates given by the device. After a registration of these two clouds, the RMS error is computed. Then, using curve fittings methods, an equation is obtained that generalizes the RMS error as a function of the distance between the sensor and the checkerboard pattern. The depth errors estimated by our method are compared to those estimated by state-of-the-art approaches, validating its accuracy and utility. This method can be used to rapidly estimate the quality of RGB-D sensors, facilitating robotics applications as SLAM and object recognition.

6.
Pediatr Pulmonol ; 52(12): 1583-1591, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29064170

RESUMEN

BACKGROUND: There are limited data on the effect of bronchopulmonary dysplasia (BPD) on sleep disordered breathing (SDB). We hypothesized that both the severity of prematurity and BPD would increase the likelihood of SDB in early childhood. Our secondary aim was to evaluate the association of demographic factors on the development of SDB. METHODS: This is a retrospective study of patient factors and overnight polysomnogram (PSG) data of children enrolled in our BPD registry between 2008 and 2015. Association between PSG results and studied variables was assessed using multiple linear regression analysis. RESULTS: One-hundred-forty children underwent at least one sleep study on room air. The mean respiratory disturbance index (RDI) was elevated at 9.9 events/hr (SD: 10.1). The mean obstructive apnea-hypopnea index (OAHI) was 6.5 (9.1) events/hr and the mean central event rate of 3.0 (3.7) events/hr. RDI had decreased by 22% or 1.5 events/hour (95%CI: 0.6, 1.9) with each year of age (P = 0.005). Subjects with more severe respiratory disease had 38% more central events (P = 0.02). Infants exposed to secondhand smoke had 2.4% lower (P = 0.04) oxygen saturation nadirs and a pattern for more desaturation events. Non-white subjects were found to have 33% higher OAHI (P = 0.05), while white subjects had a 61% higher rate of central events (P < 0.001). CONCLUSIONS: RDI was elevated in a selected BPD population compared to norms for non-preterm children. BPD severity, smoke exposure, and race may augment the severity of SDB. RDI improved with age but was still elevated by age 4, suggesting that this population is at risk for the sequelae of SDB.


Asunto(s)
Displasia Broncopulmonar/fisiopatología , Síndromes de la Apnea del Sueño/fisiopatología , Preescolar , Progresión de la Enfermedad , Exposición a Riesgos Ambientales , Femenino , Humanos , Lactante , Recién Nacido , Modelos Lineales , Masculino , Análisis Multivariante , Polisomnografía , Grupos Raciales , Contaminación por Humo de Tabaco
7.
IEEE Trans Pattern Anal Mach Intell ; 37(5): 1028-40, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26353326

RESUMEN

Clothing recognition is a societally and commercially important yet extremely challenging problem due to large variations in clothing appearance, layering, style, and body shape and pose. In this paper, we tackle the clothing parsing problem using a retrieval-based approach. For a query image, we find similar styles from a large database of tagged fashion images and use these examples to recognize clothing items in the query. Our approach combines parsing from: pre-trained global clothing models, local clothing models learned on the fly from retrieved examples, and transferred parse-masks (Paper Doll item transfer) from retrieved examples. We evaluate our approach extensively and show significant improvements over previous state-of-the-art for both localization (clothing parsing given weak supervision in the form of tags) and detection (general clothing parsing). Our experimental results also indicate that the general pose estimation problem can benefit from clothing parsing.

8.
Am J Infect Control ; 42(9): 942-56, 2014 09.
Artículo en Inglés | MEDLINE | ID: mdl-25179325

RESUMEN

We report the results of an International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2007-December 2012 in 503 intensive care units (ICUs) in Latin America, Asia, Africa, and Europe. During the 6-year study using the Centers for Disease Control and Prevention's (CDC) U.S. National Healthcare Safety Network (NHSN) definitions for device-associated health care-associated infection (DA-HAI), we collected prospective data from 605,310 patients hospitalized in the INICC's ICUs for an aggregate of 3,338,396 days. Although device utilization in the INICC's ICUs was similar to that reported from ICUs in the U.S. in the CDC's NHSN, rates of device-associated nosocomial infection were higher in the ICUs of the INICC hospitals: the pooled rate of central line-associated bloodstream infection in the INICC's ICUs, 4.9 per 1,000 central line days, is nearly 5-fold higher than the 0.9 per 1,000 central line days reported from comparable U.S. ICUs. The overall rate of ventilator-associated pneumonia was also higher (16.8 vs 1.1 per 1,000 ventilator days) as was the rate of catheter-associated urinary tract infection (5.5 vs 1.3 per 1,000 catheter days). Frequencies of resistance of Pseudomonas isolates to amikacin (42.8% vs 10%) and imipenem (42.4% vs 26.1%) and Klebsiella pneumoniae isolates to ceftazidime (71.2% vs 28.8%) and imipenem (19.6% vs 12.8%) were also higher in the INICC's ICUs compared with the ICUs of the CDC's NHSN.


Asunto(s)
Infección Hospitalaria/epidemiología , Infección Hospitalaria/prevención & control , Control de Infecciones/estadística & datos numéricos , África/epidemiología , Asia/epidemiología , Centers for Disease Control and Prevention, U.S. , Europa (Continente)/epidemiología , Humanos , Control de Infecciones/métodos , Unidades de Cuidados Intensivos , América Latina/epidemiología , Estudios Prospectivos , Estados Unidos/epidemiología
10.
Gac Med Mex ; 141(3): 215-22, 2005.
Artículo en Español | MEDLINE | ID: mdl-16025987

RESUMEN

Among the human pathologies produced by venomous animals, bee stings constitute the largest number of accidents in several countries, exceeding the mortality rate caused by other venomous animals such as snakes, spiders or scorpions. The clinical picture after the bee sting may include anaphylaxis or poisoning. The latter is produced by massive attacks and is a serious problem that may put the patient's life at risk. People that are poisoned display hemolysis, rhabdomiolysis and acute renal failure that together with other systemic failures can bring about death. The knowledge of the physiopathological mechanisms involved in the massive attack of bees is crucial for health care professionals as to date we do not have antivenoms with proven clinical efficacy. In this review we include the bee's biological aspects, venom composition and its relation with the occurrence and severity of accidents as well as epidemiological data that can be useful for this type of accidents.


Asunto(s)
Abejas , Mordeduras y Picaduras de Insectos , Animales , Venenos de Abeja/química , Venenos de Abeja/farmacología , Humanos , Mordeduras y Picaduras de Insectos/diagnóstico , Mordeduras y Picaduras de Insectos/terapia
11.
Gac. méd. Méx ; 141(3): 215-222, may.-jun. 2005. ilus
Artículo en Español | LILACS | ID: lil-632123

RESUMEN

Dentro de las patologías humanas producidas por animales con la capacidad de inocular veneno, las picaduras de abeja producen el mayor número de accidentes por animales en muchos países, superando a menudo en mortalidad a los producidos por serpientes, escorpiones y arañas. El cuadro clínico por la picadura de estos himenópteros puede consistir en fenómenos alérgicos o en cuadros de envenenamiento. Estos últimos se producen por el ataque de enjambres constituyendo un hecho grave que puede comprometer la vida. En el sujeto envenenado pueden observarse hemólisis, rabdomiólisis e insuficiencia renal, que junto a otras alteraciones sistémicas pueden conducir a la muerte. El conocimiento de los acontecimientos fisiopatológicos que se producen ante los ataques masivos de abejas es de suma importancia para el personal de salud dado que hasta la fecha no existen antivenenos que hayan demostrado tener eficacia clínica comprobada. En esta revisión se consideran los aspectos biológicos de las abejas y de la composición de su veneno relacionado con la ocurrencia y severidad de los accidentes, así como datos epidemiológicos de utilidad para enfrentarse a este tipo de cuadro.


Among the human pathologies produced by venomous animals, bee stings constitute the largest number of accidents in several countries, exceeding the mortality rate caused by other venomous animals such as snakes, spiders or scorpions. The clinical picture after the bee sting may include anaphylaxis or poisoning. The latter is produced by massive attacks and is a serious problem that may put the patient's life at risk. People that are poisoned display hemolysis, rhabdomiolysis and acute renal failure that together with other systemic failures can bring about death. The knowledge of the physiopathological mechanisms involved in the massive attack of bees is crucial for health care professionals as to date we do not ha ve antivenoms with proven clinical efficacy. In this review we include the bee's biological aspects, venom composition and its relation with the occurrence and severity of accidents as well as epidemiological data that can be useful for this type of accidents.


Asunto(s)
Animales , Humanos , Abejas , Mordeduras y Picaduras de Insectos , Venenos de Abeja/química , Venenos de Abeja/farmacología , Mordeduras y Picaduras de Insectos/diagnóstico , Mordeduras y Picaduras de Insectos/terapia
12.
Gac Med Mex ; 141(1): 13-21, 2005.
Artículo en Español | MEDLINE | ID: mdl-15754746

RESUMEN

The characterization of the toxic activities of snake venoms is necessary to understand the physiopathology of the envenomation and to test the potency of the antivenoms used to treat this pathology. Because of the lack of data on the toxic activities of venoms from Mexican snakes of medical importance, we studied the venoms from Bothrops asper, Athropoides nummifrr, Agkistrodon billineatus, Crotalus durissus durissus, Crotalus basiliscus, Crotalus scutulatus, Crotalus atrox and Micrurus nigrocinctus. The studies performed were: SDS-PAOE, determination of lethal potency, hemorrhagic, necrotizing, coagulation on plasma and fibrinogen, phospholipasic and fibri(noge)nolytic activities. In addition we studied the neutralizing capacity of the toxic activities of an antivenom currently used for the treatment of snakebites in Mexico. The venom from viperids showed important hemorrhagic, necrotizing, coagulative on plasma, prothrombinic, fibrinogenolytic and phospholipase activities. The venoms with the highest lethal potency were those of Micrurus nigrocinctus and Crotalus scutulatus; however, the viperine venom that globally displayed the most potent toxic activities was from Bothrops asper. All the venoms showed toxic activities of similar range to those described for other American venomous snakes. The activity on plasma or fibrinogen varied widely among the different venoms but all displayed capacity to act on the coagulation system. The antivenom tested not only neutralized the lethality B. asper venom but also its other toxic activities.


Asunto(s)
Venenos de Serpiente/toxicidad , Animales , México , Ratones
13.
Gac. méd. Méx ; 141(1): 13-21, ene.-feb. 2005. ilus, tab
Artículo en Español | LILACS | ID: lil-632105

RESUMEN

La caracterización de las actividades tóxicas de los venenos de serpientes es necesaria para el cabal entendimiento de los procesos fisiopatológicos que se producen ante su mordedura, como también para evaluar la potencia neutralizante de los antivenenos utilizados para tratar estos envenenamientos. A causa de los pocos datos disponibles sobre la toxicidad del veneno de serpientes con importancia sanitaria en México, estudiamos las actividades tóxicas de los venenos de Bothrops asper, Athropoides nummifer, Agkistrodon billineatus> Crotalus durissus durissus, Crotalus basiliscus, Crotalus scutulatus, Crotalus atrox y Micrurus nigrocinctus. A los venenos se les realizaron los siguientes estudios: SDS-PAUE, determinación de la potencia letal, y de las actividades hemorrágica, necrotizante, coagulante en plasma y fibrinógeno, fosfolipásica y fibrinogenolítica. Se estudió además la capacidad neutralizante de un antiveneno de uso corriente para la terapéutica de las mordeduras de serpientes venenosas en México, sobre varias de estas actividades. Los venenos de vipéridos mostraron actividades hemorrágicas, necrotizante, coagulante sobre plasma, protrombínica, fibrinogenolítica y fosfolipásica importantes. Los venenos de mayor potencia letal fueron los de Micrurus nigrocinctus y Crotalus scutulatus, sin embargo el veneno que presentó en general potencias tóxicas mayores fue el de Bothrops asper. Las diferentes potencias tóxicas halladas se encontraron dentro de los márgenes descritos para especies de vipéridos y elápidos de Sudamérica. La actividad sobre el plasma y el fibrinógeno fue muy diferente en los diferentes venenos viperinos, sin embargo todos mostraron ser capaces de afectar componentes del sistema de la coagulación. El antiveneno probado no sólo neutralizó la letalidad del veneno sino también sus actividades tóxicas.


The characterization of the toxic activities of snake venoms is necessary to understand the physiopathology of the envenomation and to test the potency of the antivenoms used to treat this pathology. Because of the lack of data on the toxic activities of venoms from Mexican snakes of medical importance, we studied the venoms from Bothrops asper, Athropoides nummifer, Agkistrodon billineatus, Crotalus durissus durissus, Crotalus basiliscus, Crotalus scutulatus, Crotalus atrox and Micrurus nigrocinctus. The studies performed were : SDS-PAOE, determination of lethal potency, hemorrhagic, necrotizing, coagulation on plasma and fibrinogen, phospholipasic and fibrinogenolytic activities. In addition we studied the neutralizing capacity of the toxic activities of an antivenom currently used for the treatment of snakebites in Mexico. The venom from viperids showed important hemorrhagic, necrotizing, coagulative on plasma, prothrombinic, fibrinogenolytic and phospholipase activities. The venoms with the highest lethal potency were those of Micrurus nigrocinctus and Crotalus scutulatus; however, the viperine venom that globally displayed the most potent toxic activities was from Bothrops asper. All the venoms showed toxic activities of similar range to those described for other American venomous snakes. The activity on plasma or fibrinogen varied widely among the different venoms but all displayed capacity to act on the coagulation system. The antivenom tested not only neutralized the lethalityB. asper venom but also its other toxic activities.


Asunto(s)
Animales , Ratones , Venenos de Serpiente/toxicidad , México
14.
Arch. pediatr. Urug ; 70(2): 93-96, 1999.
Artículo en Español | LILACS | ID: lil-313802

RESUMEN

Se comunica el caso de un recién nacido pretérmino que luego de un breve período libre de síntomas instaló una meningoencefalitis aguda supurada por Streptococcus pneumoniae, con estado de mal convulsivo refractario al tratamiento, falla multiorgánica y evolución fulminante. Se realizan consideraciones respecto a la frecuencia de esta entidad, los mecanismos patogénicos, la letalidad y el tratamiento, a la luz de la revisión bibliográfica


Asunto(s)
Humanos , Recién Nacido , Meningitis Neumocócica/etiología , Streptococcus pneumoniae
15.
Arch. pediatr. Urug ; 70(2): 97-101, 1999. ilus
Artículo en Español | LILACS | ID: lil-313803

RESUMEN

Se presenta la observación clínica de un niño de 4 años de raza negra, que fue admitido por una crisis addisoniana. La causa más frecuente de enfermedad de Addison es la adrenalitis autoinmune. Es una entidad rara en la infancia. Guiaron el diagnóstico la avidez por la sal, la severa deshidratación y los trastornos electrolíticos refractarios al tratamiento inicial. Lo confirmaron las dosificaciones hormonales y la excelente respuesta a la corticoterapia


Asunto(s)
Humanos , Masculino , Preescolar , Enfermedad de Addison , Población Negra , Neumonía/complicaciones
16.
Arch. pediatr. Urug ; 69(2): 41-4, 1998. ilus
Artículo en Español | LILACS | ID: lil-255594

RESUMEN

Se presenta un caso de una niña de 18 meses portadora de una neumonía complicada con pioneumotorax, anemia severa, hemólisis, plaquetopenia e insuficiencia renal, con test de látex positivo para neumococo en líquido pleural. Se postula el diagnóstico de sindrome hemolítico urémico (SHU) asociado a estreptococo pneumoniae descartándose otras entidades. Se analiza esta rara asociación a la luz de la bibliografía y se efectúan consideraciones respecto del diagnóstico, fisiopatología y manejo relacionándolas con el caso presentado. Se concluye que el caso analizado podría tratarse de una forma menor de SHU asociado a neumococo que hubiera requerido de metodología diagnóstica que no estuvo al alcance de los autores (dosificación de actividad de neuraminidasa plasmática)


Asunto(s)
Humanos , Femenino , Lactante , Neumonía Neumocócica/complicaciones , Síndrome Hemolítico-Urémico/complicaciones , Síndrome Hemolítico-Urémico/diagnóstico , Insuficiencia Renal , Síndrome Hemolítico-Urémico/terapia
17.
s.l; s.n; 1948. 14 p.
No convencional en Español | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1233376

Asunto(s)
Lepra
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