Transcervical Vertebral Artery Origin Endarterectomy for Vertebrobasilar Insufficiency.

Vertebral artery (VA) stenosis is a cause of vertebrobasilar insufficiency (VBI) and disabling posterior circulation stroke,1 accounting for up to 30% of all strokes.2 Although the natural history of VBI is not as well delineated as that of carotid stenosis, strokes in the basilar circulation can be more disabling than their anterior circulation counterparts. Stenosis exceeding 30% at the origin of the vertebral artery is associated with increased risk of stroke.3 The authors present a case of a female patient with significant peripheral vascular disease who presented with concerns for VBI. The patient was on antiplatelet and anticoagulative medications and a statin at the time of her presentation. Angiography demonstrated bilateral vertebral artery origin stenosis. The left VA was diminutive and arose directly from the arch (Video 1). The right VA demonstrated critical stenosis at its origin. Attempts at endovascular access of the right VA for placement of a balloon-mounted stent were unsuccessful. The patient underwent a transcervical approach for endarterectomy of the VA origin. The VA can be readily accessed using a small supraclavicular incision to isolate the V1 segment of the vessel. The procedure was performed with the patient heparinized and on antiplatelet medications. Alternatives to this strategy include patch grafting in addition to the endarterectomy or use of a short vein graft to bypass the stenosis of the VA beyond the stenotic segment.

Integrating eddy fluxes and remote sensing products in a rotational grazing native tallgrass prairie pasture.

Eddy covariance (EC) systems provide integrated fluxes within their footprint areas. Spatial heterogeneity of up-scaled areas and spatio-temporal mismatches between EC footprint and remote sensing pixels jeopardize the performance of most satellite-based models. To examine the impact of spatial resolution of satellite products on up-scaling of fluxes, we compared the relationships between measured eddy fluxes and enhanced vegetation index (EVI) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) at 500 and 250 m spatial resolutions, Visible Infrared Imaging Radiometer Suite (VIIRS) at 500 m spatial resolution, and Landsat at 30 m spatial resolution but integrated at the paddock-scale. The experiment was conducted over a grazed native tallgrass prairie pasture, which was divided into nine paddocks for rotational grazing. The EVI data from all satellites showed consistency in detecting vegetation phenology. Seasonality of EC-measured fluxes corresponded well with remotely-sensed vegetation phenology. Approximately 80% of contribution to eddy fluxes came from within 80 m upwind distance of the 2.7 m tall EC tower. As a result, the major contributing area for the measured fluxes was mostly limited to the paddock containing the EC tower. Different timings and duration of grazing caused some heterogeneity among paddocks within the pasture. The EVI of different spatial scales showed strong relationships with CO2 fluxes. However, Landsat-derived EVI integrated for the paddock containing the EC tower showed substantially stronger relationships with CO2 fluxes than did MODIS and VIIRS-derived EVI integrated for multiple paddocks, most likely due to similar spatial resolutions of remote sensing and EC observations. Results illustrate that satellite products of fine-scale spatial resolution that are comparable to EC footprints can help improve the performance of satellite-based models for modeling or up-scaling of eddy fluxes, especially in heterogeneous ecosystems.

Dynamics of CO2 and H2O fluxes in Johnson grass in the U.S. Southern Great Plains.

Johnson grass (Sorghum halepense (L.) Pers.) is rapidly spreading throughout the continental United States (U.S.). Thus, determining magnitudes and seasonal dynamics of carbon dioxide (CO2) and water vapor (H2O) fluxes in Johnson grass is crucial to understand regional changes in hydrology and carbon balance. Using eddy covariance (EC), CO2 and H2O fluxes were measured from June 2017 to October 2019 over a rainfed Johnson grass field in central Oklahoma. Hay was harvested from late May to early July each year, with biomass yield ~7.5 t ha-1. Weekly averaged daily integrated net ecosystem CO2 exchange (NEE), gross primary production (GPP), and evapotranspiration (ET) reached -8.28 ± 0.76 g C m-2, 20.02 ± 1.62 g C m-2, and 5.42 ± 0.26 mm, respectively. Ecosystem water use efficiency (EWUE) and ecosystem light use efficiency (ELUE) ranged from 3.22 to 3.93 g C mm-1 ET and 0.34 to 0.41 g C mol-1 PAR (photosynthetically active radiation), respectively, during peak growths. Based on aggregated fluxes for each month over the three years (2017-2019), cumulative annual NEE was -434 ± 112 g C m-2, indicating a carbon gain by the Johnson grass field. Cumulative annual ET (858 ± 72 mm) was ~86% of the average annual rainfall (996 ± 100 mm). Results showed Johnson grass could be a carbon sink from May to September in the U.S. Southern Great Plains. Both NEE and ET did not decline up to air temperature (Ta) of ~33 °C and vapor pressure deficit (VPD) of ~2 kPa, suggesting optimum Ta of ≥33 °C and VPD of ≥2 kPa for the fluxes. Results indicated that Johnson grass might be well suited for dryland production in the region. Additionally, these findings provide initial baseline information on CO2 fluxes and ET for Johnson grass relative to other forage species in the region.

Adult cardiac veno-arterial extracorporeal life support (VA-ECMO): prevention and management of acute complications.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has been shown to be a viable and effective treatment for patients suffering from refractory cardiogenic shock (rCS), which is associated with high mortality rates. Although ECMO therapy used as short-term mechanical circulatory support (MCS) has shown tremendous growth in its application over the past decade, the complication and mortality rates remain high. This retrospective study analyzes complications associated with VA-ECMO support, evaluates the use of defined protocols at a single center, and examines factors that may contribute to patient complication and mortality. METHODS: This retrospective analysis included 184 patients who were supported with ECMO from September 2014 through March 2018 at Integris Baptist Medical Center (IBMC). Descriptive statistics were generated to analyze baseline characteristics, demographics, complications, and outcomes. RESULTS: Acute myocardial infarct (AMI) was the primary etiology of this cohort (N=40; 22%). The mean age was 55±15 (median 56, range 15-84) years. All patients were inotrope and/or vasopressor dependent prior to ECMO initiation. Mean time on ECMO support was 7.8±7.9 days with median time of 6 days. Total patient days on support were 1,430. Most ECMO cannulations, 97 (52%) were performed within Integris Baptist Medical Center, with 48% done outside the hospital; 38% were performed outside of the hospital by the IBMC ECMO team, and 10.5% were performed by an outside team. Bleeding was noted to be the most common VA ECMO complication [N=41; 22.3%; 0.028 events per patient day (EPPD)]. CONCLUSIONS: A dedicated 24/7 ECMO service using a multidisciplinary team (MDT) and defined protocols in a single center is able to effectively reduce complications due to VA-ECMO support in the sickest of the sick VA-ECMO patients.

Fatty acid composition of traditional and novel forages.

Managing the fatty acid composition of grazing ruminant diets could lead to meat and milk products that have higher conjugated linoleic acid (CLA) concentrations, but forage fatty acid dynamics must be more fully understood for a range of forages before grazing systems can be specified. The fatty acid profiles of 13 different forages, including grasses, legumes, and forbs, grown under greenhouse conditions, were determined. Three separate harvests, at 3-week intervals, were made of each plant material. alpha-Linolenic [C18:3, 7.0-38.4 mg g(-1) of dry matter (DM)], linoleic (C18:2, 2.0-10.3 mg g(-1) of DM), and palmitic (C16:0, 2.6-7.5 mg g(-1) of DM) acids were the most abundant fatty acids in all species at each harvest, together representing approximately 93% of the fatty acids present. Concentrations of fatty acids declined as plants developed, but the fractional contribution of each fatty acid to total fatty acids remained relatively stable over time. Grasses had a uniform composition across species with a mean of 66% of total fatty acids provided by C18:3, 13% by C18:2, and 14% by C16:0. The fractional contribution of C18:3 to total fatty acids was lower and more variable in forbs than in grasses. Intake of fatty acid by grazing ruminants would be affected by the forage species consumed.

A genome scanning approach to assess the genetic effects of radiation in mice and humans.

We used Restriction Landmark Genome Scanning (RLGS) to assess, on a genome-wide basis, the mutation induction rate in mouse germ cells after radiation exposure. Analyses of 1,115 autosomal NotI DNA fragments per mouse for reduced spot intensity, indicative of loss of one copy, in 506 progeny derived from X-irradiated spermatogonia (190, 237 and 79 mice in 0-, 3-, and 5-Gy groups, respectively), permitted us to identify 16 mutations affecting 23 fragments in 20 mice. The 16 mutations were composed of eight small changes (1-9 bp) at microsatellite sequences, five large deletions (more than 25 kb), and three insertions of SINE B2 or LINE1 transposable elements. The maximum induction rate of deletion mutations was estimated as (0.17 +/- 0.09) x 10(-5)/locus Gy(-1). The estimate is considerably lower than 1 x 10(-5)/locus Gy(-1), the mean induction rate of deletion mutations at Russell's 7 loci, which assumed that deletion mutations comprise 50% of all mutations. We interpret the results as indicating that the mean induction rate of mutations in the whole genome may be substantially lower than that at the 7 loci. We also demonstrate the applicability of RLGS for detection of human mutations, which allows direct comparisons between the two species.

Blood polymorphisms and morphological variability in Brazilian Indians.

A total of 1,025 adults belonging to four Brazilian tribes were simulataneously studied for 12-16 anthropometric characteristics and 7-11 blood polymorphic loci. Several comparisons using both univariate and multivariate statistical techniques failed to show the negative correlation between these two sets of variables found by other workers. © 1994 Wiley-Liss, Inc.

A study of the level and dynamics of Eimeria populations in naturally infected, grazing beef cattle at various stages of production in the Mid-Atlantic USA.

There is little information available on the species dynamics of eimerian parasites in grazing cattle in the central Appalachian region of the United States. Therefore, the objective of this study was to describe the level of infection and species dynamics of Eimeria spp. in grazing beef cattle of various age groups over the course of a year in the central Appalachian region. Rectal fecal samples were collected from male and female calves (n=72) monthly from May through October 2005, heifers only (n=36) monthly from November 2005 to April 2006, and cows (n=72) in May, July, and September, 2005. Eimeria spp. oocysts were seen in 399 of 414 (96%) fecal samples collected from the calves from May through October. Fecal oocysts counts (FOC) in the calves were lower (P<0.05) in May than all other months and no significant differences were detected from June through September. Eimeria spp. oocysts were detected in 198 of 213 (92%) of fecal samples collected from the 36 replacement heifers monthly from November to April and monthly mean FOC did not differ during this time period. The prevalence of oocyst shedding increased to 100% in calves in September and remained near 100% in the replacement heifers during the sampling period. Eimeria spp. oocysts were also detected in 150 of 200 (75%) samples collected in May, July, and September from the cows and mean FOC did not differ significantly over the sampling period. Eimeria spp. composition was dominated by Eimeria bovis in fecal samples collected from calves, replacement heifers and cows. Mixed Eimeria spp. infections were, however, common in all groups and 13 Eimeria spp. oocysts were identified throughout the sampling period.

The newly characterized colicin Y provides evidence of positive selection in pore-former colicin diversification.

Two evolutionary mechanisms have been proposed in the process of protein diversification of the large family of antimicrobial toxins of Escherichia coli, known as the colicins. Data from previous studies suggest that the relatively rare nuclease colicins appear to diversify primarily through the action of positive selection, whilst the more abundant pore-former colicins appear to diversify through the action of recombination. The complete DNA sequence of the newly characterized colicin plasmid, pCol-Let, isolated from a Yanomama Indian of South America, is presented here. This plasmid encodes a newly identified pore-former colicin, colicin Y. DNA and protein sequence comparisons of the colicin Y gene cluster and the encoded proteins with those of published pore-former colicins provide the first evidence that positive selection may also act to increase pore-former colicin diversity.

Evolutionary health promotion.

Health promotion's promise is enormous, but its potential is, as yet, unmatched by accomplishment. Life expectancy increases track more closely with economic prosperity and sanitary engineering than with strictly medical advances. Notable achievements in the past century--the decreased incidences of epidemic infections, dental caries, and stomach cancer--are owed to virologists, dentists, and (probably) refrigeration more than to physicians. Prevention speaks against tobacco abuse with a single voice, but in many other areas contradictory research findings have generated skepticism and even indifference among the general public for whom recommendations are targeted. Health promotion's shortcomings may reflect lack of an overall conceptual framework, a deficiency that might be corrected by adopting evolutionary premises: (1) The human genome was selected in past environments far different from those of the present. (2) Cultural evolution now proceeds too rapidly for genetic accommodation--resulting in dissociation between our genes and our lives. (3) This mismatch between biology and lifestyle fosters development of degenerative diseases. These principles could inform a research agenda and, ultimately, public policy: (1) Better characterize differences between ancient and modern life patterns. (2) Identify which of these affect the development of disease. (3) Integrate epidemiological, mechanistic, and genetic data with evolutionary principles to create an overarching formulation upon which to base persuasive, consistent, and effective recommendations.

Control de las enfermedades de los ameridios en transición cultural / Control of diseases among ameridians in cultural transition

Es difícil pronosticar los efectos de cualquier medida externa sobre grupos ameridios con quienes se establecerá un nuevo contacto. Por esta razón ocurre que algunas medidas clásicas, entre ellas las de salud, destinadas a beneficiar a estos grupos, producen efectos secundarios perjudiciales. En este artículo se examinan estos efectos y se sugieren varios procedimientos para evitarlos o dominarlos

The American Indian in the international biological program

Meeting of the Advisory Committee on Medical Research, 7. Pan American Health Organization; 24-28 Jun. 1968

Control of disease in Amerindians in cultural transition

Meeting of the Advisory Committe on Medical Research, 13. Pan American Health Organization; 24-28 Jun. 1974

Estudos epidemiológicos entre populações ameríndias da amazônia. iii. parasitoses intestinais em povoações recentemente contactadas e em aculturação

SUMMARY The prevalences of intestinal parasites among the residents of three South American Indian villages in the process of acculturation were compared with those found in earlier unpublished surveys in two newly contacted villages. Although one individual in an acculturating village harbored 11 different intestinal parasites, in general, the average number of different parasitic species carried per person was somewhat higher in the newly contacted villages. Helminth egg counts, performed on direct smears of each specimen from one newly contacted village, were low. There were no sex-associated differences in prevalences. The overall prevalences, unadjusted for age, were among the highest recorded for Amerindians. No Taenia species were present. Balantidium coli was present in two acculturating villages, concommitant with the beginnings of agricultural practices which include raising swine. No cases of moderate or severe protein-calorie malnutrition were observed in any of the villages during the surveys. These limited data provide a baseline for future comparisons, and, perhaps, a glimpse into the past.

Resumo Os predomínios de parasitas intestinais entre os residentes de três povoações de índios sul-americanos no processo de aculturação foram comparados com os encontrados em pesquisas anteriores, não publicadas, em duas povoações recentemente contactadas. Embora um indivíduo, em uma povoação, em aculturação, hospedasse 11 diferentes parasitas intestinais, em geral, o número médio de diferentes espécies de parasitas por pessoa era um tanto maior nas povoações recentemente contactadas. A contagem de ovos de helmintos, efetuada diretamente nas sujeiras de cada espécime de uma vila recentemente contactada, foi baixa. Não houve diferenças em predomínio associadas ao sexo. Os predomínios totais, não ajustados por idade, estavam entre os mais altos registrados para ameríndios. Nenhuma espécie de Taenia ocorreu. Balantidium coli ocorreu em duas vilas em aculturação, concomitante com o início de práticas agrícolas que incluem criação de suínos. Nenhum caso de má nutrição de caloria protéica moderada ou severa foi observado em qualquer das vilas durante as pesquisas. Estes limitados dados fornecem uma linha base para futuras comparações, e, talvez, um olhar rápido no passado.

Estudos epidemiologicos entre populaçoes Amerindias da Amazonia. III. Parasitoses intestinais em povoaçoes recentemente contactadas e em aculturaçao / Epidemiologic studies among Amerindian populations of Amazonia. III.Intestinal parasitosis in populations recently contacted and in process of acculturation

Os predominios de parasitas intestinais entre os residentes de tres povoaçoes de indios sul-americanos no processo de aculturaçao foram comparados com os encontrados em pesquisas anteriores, nao publicadas, em duas povoaçoes recentemente contactadas. Embora um individuo, em uma povoaçao, em aculturaçao, hospedasse 11 diferentes parasitas intestinais, em geral, o numero medio de diferentes especies de parasitas por pessoa era tanto maior nas povoaçoes recentemente contactadas. A contagem de ovos de helmintos, efetuada diretamente nas sujeiras de cada especime de uma vila recentemente contactada, foi baixa. Nao houve diferenças em predominio associadas ao sexo. Os predominios totais, nao ajustados por idade, estavam entre os mais altos reegistrados para amerindios. Nenhuma especie de Taenia ocorreu. Balastidium coli ocorreu em duas vilas em aculturaçao, concomitante com o inicio de praticas agricolas que incluem criaçao de suinos. Nenhum caso de ma nutriçao de caloria protica moderada ou severa foi observado em qualquer das vilas durante as pesquisas. Estes limitados dados fornecem uma linha base para futuras comparaçoes, e, talvez, um olhar rapido no passado