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1.
Invertebr Syst ; 382024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39116275

RESUMEN

During the past two decades, the phylogenetic relationships and higher-level classification of the subfamily Rogadinae have received relevant contributions based on Sanger, mitogenome and genome-wide nuclear DNA sequence data. These studies have helped to update the circumscription and tribal classification of this subfamily, with six tribes currently recognised (Aleiodini, Betylobraconini, Clinocentrini, Rogadini, Stiropiini and Yeliconini). The tribal relationships within Rogadinae, however, are yet to be fully resolved, including the status of tribe Facitorini, previously regarded as betylobraconine, with respect to the members of Yeliconini. We conducted a phylogenomic analysis among the tribes of Rogadinae based on genomic ultraconserved element (UCE) data and extensive taxon sampling including three undescribed genera of uncertain tribal placement. Our almost fully supported estimate of phylogeny confirmed the basal position of Rogadini within the subfamily and a Facitorini clade (Yeliconini+Aleiodini) that led us to propose the former group as a valid rogadine tribe (Facitorini stat. res.). Stiropiini, however, was recovered for the first time as sister to the remaining rogadine tribes except Rogadini, and Clinocentrini as sister to a clade with Betylobraconini+the three undescribed genera. The relationships recovered and morphological examination of the material included led us to place the latter three new genera and recently described genus Gondwanocentrus within a new rogadine tribe, Gondwanocentrini Shimbori & Zaldívar-Riverón trib. nov. We described these genera (Ghibli Shimbori & Zaldívar-Riverón gen. nov., Racionais Shimbori & Zaldívar-Riverón gen. nov. and Soraya Shimbori gen. nov.) with two or three new species each (G. miyazakii Shimbori & Zaldívar-Riverón sp. nov., G. totoro Shimbori & Zaldívar-Riverón sp. nov., R. brunus Shimbori & Zaldívar-Riverón sp. nov., R. kaelejay Shimbori & Zaldívar-Riverón sp. nov., R. superstes Shimbori & Zaldívar-Riverón sp. nov., S. alencarae Shimbori sp. nov. and S. venus Shimbori & Zaldívar-Riverón sp. nov.). A new species of Facitorini, Jannya pasargadae Gadelha & Shimbori sp. nov., is also described. Our newly proposed classification expands the number of tribes and genera within Rogadinae to 8 and 66 respectively. ZooBank: urn:lsid:zoobank.org:pub:51951C78-069A-4D8B-B5F0-7EBD4D9D21CE.


Asunto(s)
Filogenia , Avispas , Animales , Avispas/genética , Avispas/clasificación , Avispas/anatomía & histología , Especificidad de la Especie , Mariposas Nocturnas/genética , Mariposas Nocturnas/parasitología
2.
Invertebr Syst ; 382024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38740060

RESUMEN

Mitochondrial DNA gene organisation is an important source of phylogenetic information for various metazoan taxa at different evolutionary timescales, though this has not been broadly tested for all insect groups nor within a phylogenetic context. The cosmopolitan subfamily Doryctinae is a highly diverse group of braconid wasps mainly represented by ectoparasitoids of xylophagous beetle larvae. Previous molecular studies based on Sanger and genome-wide (ultraconserved elements, UCE; and mitochondrial genomes) sequence data have recovered a non-monophyletic Doryctinae, though the relationships involved have always been weakly supported. We characterised doryctine mitogenomes and conducted separate phylogenetic analyses based on mitogenome and UCE sequence data of ~100 representative doryctine genera to assess the monophyly and higher-level classification of the subfamily. We identified rearrangements of mitochondrial transfer RNAs (tRNAs) that support a non-monophyletic Doryctinae consisting of two separate non-related clades with strong geographic structure ('New World' and 'Old World' clades). This geographic structure was also consistently supported by the phylogenetic analyses preformed with mitogenome and UCE sequence data. These results highlight the utility of the mitogenome gene rearrangements as a potential source of phylogenetic information at different evolutionary timescales.


Asunto(s)
Genoma Mitocondrial , Filogenia , Avispas , Animales , Avispas/genética , Genoma Mitocondrial/genética , Genoma de los Insectos
3.
Zookeys ; (747): 87-100, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29674905

RESUMEN

A revision of the small Afrotropical holcobraconine genus Ivondrovia Shenefelt & Marsh, 1976 (Doryctinae) is provided. A new species from Kenya, Ivondrovia grangerisp. n., is described and illustrated. The illustrated redescriptions of the genus Ivondrovia and its type species Lophogaster seyrigi Granger, 1949 are given. The two known species of this genus are keyed.

4.
Artículo en Inglés | MEDLINE | ID: mdl-26214744

RESUMEN

Stroke is the most devastating complication after ventricular assist device (VAD) implantation with a 19% incidence and 65% mortality in the pediatric population. Current pediatric VAD technology and anticoagulation strategies alone are suboptimal. VAD implantation assisted by computational methods (CFD) may contribute reducing the risk of cerebral embolization. Representative three-dimensional aortic arch models of an infant and a child were generated. An 8 mm VAD outflow-graft (VAD-OG) anastomosed to the aorta was rendered and CFD was applied to study blood flow patterns. Particle tracks, originating in the VAD, were computed with a Lagrangian phase model and the percentage of particles entering the cerebral vessels was calculated. Eight implantation configurations (infant = 5 and child = 3) and 5 particle sizes (0.5, 1, 2, 3, and 4 mm) were considered. For the infant model, percentage of particles entering the cerebral vessels ranged from 15% for a VAD-OG anastomosed at 90° to the aorta, to 31% for 30° VAD-OG anastomosis (overall percentages: X(2) = 10,852, p < 0.0001). For the child model, cerebral embolization ranged from 9% for the 30° VAD-OG anastomosis to 15% for the 60° anastomosis (overall percentages: χ(2) = 10,323, p < 0.0001). Using detailed CFD calculations, we demonstrate that the risk of stroke depends significantly on the VAD implantation geometry. In turn, the risk probably depends on patient-specific anatomy. CFD can be used to optimize VAD implantation geometry to minimize stroke risk.


Asunto(s)
Biología Computacional , Simulación por Computador , Corazón Auxiliar/efectos adversos , Embolia Intracraneal/prevención & control , Aorta/fisiología , Aorta Torácica/fisiología , Niño , Hemodinámica , Humanos , Lactante , Modelos Biológicos , Accidente Cerebrovascular/prevención & control
5.
J Biomech Eng ; 136(7)2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24441718

RESUMEN

Stroke is the most devastating complication after ventricular assist device (VAD) implantation, with an incidence of 14%-47% despite improvements in device design and anticoagulation. This complication continues to limit the widespread implementation of VAD therapy. Patient-specific computational fluid dynamics (CFD) analysis may elucidate ways to reduce this risk. A patient-specific three-dimensional model of the aortic arch was generated from computed tomography. A 12 mm VAD outflow-graft (VAD-OG) "anastomosed" to the aorta was rendered. CFD was applied to study blood flow patterns. Particle tracks, originating from the VAD, were computed with a Lagrangian phase model and percentage of particles entering the cerebral vessels was calculated. Twelve implantation configurations of the VAD-OG and three particle sizes (2, 4, and 5 mm) were considered. Percentage of particles entering the cerebral vessels ranged from 6% for the descending aorta VAD-OG anastomosis, to 14% for the ascending aorta at 90 deg VAD-OG anastomosis. Values were significantly different among all configurations (X(2) = 3925, p < 0.0001). Shallower and more cephalad anastomoses prevented formation of zones of recirculation in the ascending aorta. In this computational model and within the range of anatomic parameters considered, the percentage of particles entering the cerebral vessels from a VAD-OG is reduced by nearly 60% by optimizing outflow-graft configuration. Ascending aorta recirculation zones, which may be thrombogenic, can also be eliminated. CFD methods coupled with patient-specific anatomy may aid in identifying the optimal location and angle for VAD-OG anastomosis to minimize stroke risk.


Asunto(s)
Vasos Sanguíneos , Corazón Auxiliar/efectos adversos , Embolia Intracraneal/etiología , Embolia Intracraneal/prevención & control , Modelación Específica para el Paciente , Prótesis e Implantes , Aorta Torácica/fisiopatología , Vasos Sanguíneos/fisiopatología , Humanos , Hidrodinámica , Tamaño de la Partícula , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control
6.
Artículo en Inglés | MEDLINE | ID: mdl-22185643

RESUMEN

BACKGROUND: Currently, mechanical support is the most promising alternative to cardiac transplantation. Ventricular assist devices (VADs) were originally used to provide mechanical circulatory support in patients awaiting planned heart transplantation ('bridge-to-transplantation' therapy). The success of short-term bridge devices led to clinical trials evaluating the clinical suitability of long-term support ('destination' therapy) with left ventricular assist devices (LVADs). The first larger scale, randomised trial that tested long-term support with an LVAD reported a 44% reduction in the risk of stroke or death in patients with an LVAD. In spite of the success of LVADs as bridge-to-transplantation and long-term support, patients managed by these devices are still at risk of several adverse events. The most devastating complication is caused by embolisation of thrombi formed within the LVAD or inside the heart into the brain. Prevention of thrombi formation is attempted through anticoagulation management and by improving LVADs design; however, there is still significant occurrence of thromboembolic events in patients. Investigators have reported that the incidence of thromboembolic cerebral events ranges from 14% to 47% over a period of 6-12 months. METHODS AND APPROACH: An alternative method to reduce the incidence of cerebral embolisation is proposed by the co-authors, and the hypothesis is that it is possible to minimise the number of thrombi flowing into the carotid and vertebral arteries by an optimal placement of the LVAD outflow conduit, with or without the addition of aortic bypass connecting the ascending aorta and the innominate artery (IA), or left carotid artery. This paper presents the computational fluid dynamics (CFD) analysis of the aortic arch haemodynamics using a representative geometry of the human aortic arch with or without an alternative aortic bypass. In order to study the trajectory of the thrombi within the aortic arch bed, the CFD code, Fluent 6.3, is utilised to resolve the flow field and to solve the Lagrangian particle tracking of thrombi released randomly at the inlet of the LVAD cannula. RESULTS: Results are presented for simulations of thrombi in the range of 2-5 mm. The percentage of individual diameter as well as aggregate diameter thrombi flowing to the carotid and vertebral arteries as a function of LVAD conduit placement and aortic bypass implantation is reported. The influence of the LVAD conduit implantation and bypass reveals a nearly 50% variation in predicted cerebral embolism rates. CONCLUSIONS: The adjustment of the location of the anastomosis of the LVAD outflow cannula as well as its angle of incidence plays a significant role in the level of thromboembolisms. By proper adjustment in this CFD study of a synthetic model of an aortic arch bed, we found that nearly a 50% reduction in cerebral embolism could be achieved for a configuration consisting of a shallow angle of implantation over a baseline normal incidence of the LVAD cannula. Within the limitations of our model, we have established that the LVAD implantation geometry is an important factor and should be taken into consideration when implanting an LVAD. It is possible that other parameters such as distance of the LVAD outflow cannula to the root of the IA could affect the thrombi embolisation probabilities. However, the results of this study suggest that the risk of stroke may be significantly reduced by as much as 50% by tailoring the VAD implantation by a simple surgical manoeuvre. The results of this line of research may ultimately lead to techniques that can be used to estimate the optimal LVAD configuration in a patient-specific manner by pre-operative imaging.


Asunto(s)
Aorta Torácica , Procedimientos Quirúrgicos Cardíacos/métodos , Ventrículos Cardíacos/cirugía , Corazón Auxiliar/efectos adversos , Accidente Cerebrovascular/prevención & control , Aorta Torácica/anatomía & histología , Aorta Torácica/fisiología , Aorta Torácica/cirugía , Simulación por Computador , Femenino , Hemodinámica , Humanos , Embolia Intracraneal/etiología , Embolia Intracraneal/prevención & control , Masculino , Modelos Anatómicos , Accidente Cerebrovascular/etiología , Tromboembolia/etiología , Tromboembolia/prevención & control
7.
Ann Thorac Surg ; 94(5): 1540-50, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22981256

RESUMEN

BACKGROUND: The hemodynamics characteristics of the hybrid Norwood (HN) procedure differ from those of the conventional Norwood and are not fully understood. We present a multiscale model of HN circulation to understand local hemodynamics and effects of aortic arch stenosis and a reverse Blalock-Taussig shunt (RBTS) on coronary and carotid perfusion. METHODS: Four 3-dimensional models of four HN anatomic variants were developed, with and without 90% distal preductal arch stenosis and with and without a 4-mm RBTS. A lumped parameter model of the circulation was coupled to a local 3-dimensional computational fluid dynamics model. Outputs from the lumped parameter model provided waveform boundary conditions for the computational fluid dynamics model. RESULTS: A 90% distal arch stenosis reduced pressure and net flow-rate through the coronary and carotid arteries by 30%. Addition of the RBTS completely restored pressure and flow rate to baseline in these vessels. Zones of flow stagnation, flow reversal, and recirculation in the presence of stenosis were rendered more orderly by addition of the RBTS. In the absence of stenosis, presence of the shunt resulted in extensive zones of disturbed flow within the RBTS and arch. CONCLUSIONS: We found that a 4-mm × 21-mm RBTS completely compensated for the effects of a 90% discrete stenosis of the distal aortic arch in the HN. Placed preventatively, the RBTS and arch displayed zones with thrombogenic potential showing recirculation and stagnation that persist for a substantial fraction of the cardiac cycle, indicating that anticoagulation should be considered with a prophylactic RBTS.


Asunto(s)
Aorta Torácica/fisiopatología , Estenosis de la Válvula Aórtica/fisiopatología , Procedimiento de Blalock-Taussing , Modelos Cardiovasculares , Procedimientos de Norwood , Flujo Sanguíneo Regional , Humanos , Imagenología Tridimensional
8.
Appl Environ Microbiol ; 73(3): 1025-8, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17142354

RESUMEN

Recent outbreaks of human tuberculosis in the United States caused by Mycobacterium bovis have implicated cheese originating in Mexico as a source of these infections. A total of 203 samples of cheese originating in Mexico were cultured, and M. bovis was recovered from one specimen. Therefore, M. bovis can be recovered from cheese and may be a source of human infections.


Asunto(s)
Queso/microbiología , Mycobacterium bovis/aislamiento & purificación , Tuberculosis/transmisión , Animales , Bovinos , Medios de Cultivo , Humanos , México/epidemiología , Mycobacterium bovis/clasificación , Mycobacterium bovis/genética , Tuberculosis/epidemiología , Tuberculosis/microbiología , Tuberculosis Bovina/epidemiología , Tuberculosis Bovina/microbiología , Tuberculosis Bovina/transmisión
9.
Rev. venez. anestesiol ; 6(1): 22-27, jun. 2001. tab
Artículo en Español | LILACS | ID: lil-365074

RESUMEN

Actualmente existe gran interés acerca del despertar intraoperatorio. El objetivo de nuestro estudio es evaluar la capacidad que tiene un valor de índice biespectral, al utilizar dos dosis diferentes de fentanyl (1µg/kg vs 3µg/kg), es predecir incrementos en la actividad cortical cerebral y en la respuesta hemodinámica durante la laringoscopia e intubación orotraqueal. Se estudiaron 29 pacientes ASA I y II escogidos al azar para recibir fentanyl 1 µg/kg (grupo A = 14) o fentanyl 3 µg/kg ( grupo B = 15), después de la inducción anestésica con propofol 2 - 2,5 mg/kg, se realizó la intubación orotraqueal 3 minutos después de administrado el opiáceo y asegurándose un valor de índice biespectral< de 50. Los valores del índice biespectral y las variables hemodinámicas fueron anotadas inicialmente, preintubación y pos-intubación. Se observó una mayor respuesta hemodinámica a la laringoscopia e intubación orotraqueal en el grupo A en comparación con el grupo B; evidenciándose incrementos de la tensión arterial media frecuencia cardíaca en el grupo A y sólo incrementos en la tensión arterial diastólica y frecuencia cardíaca en el grupo B. En el grupo A hubo un aumento significativo en el valor de índice biespectral pos intubación cuando se comparó con los valores de pre intubación, sin existir diferencias en el grupo B. En conclusión un valor de índice biespectral< de 50 fue efectivo para predecir incremento en la actividad cortical cerebral y hemodinámicos producidos por la laringoscopia e intubación orotraqueal en los pacientes que recibieron fentanyl 3 µg/kg, pero no lo fue en el grupo de pacientes que recibió el fentanyl 1 µg/kg


Asunto(s)
Humanos , Fentanilo , Anestesia , Laringoscopía , Intubación Intratraqueal , Hemodinámica , Venezuela , Anestesiología
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