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Hemicolectomía en un paciente con valvulopatía aórtica: reporte de caso
No full textResumenLos pacientes con enfermedad valvular presentan mayor riesgo de complicaciones perioperatorias en el contexto de cirugía no cardiaca. La importancia del anestesiólogo desde la consulta de preanestesia para valorar la severidad de la enfermedad y su intervención activa es determinante.El manejo de este caso clínico se reporta para poner en valor la necesidad que tiene el paciente cardiópata de ser atendido de manera multidisciplinar.Presentamos el caso de un paciente de 80 años con estenosis aórtica severa, aneurisma de aorta abdominal infrarrenal de 46mm; enfermedad pulmonar obstructiva crónica, hipertensión arterial controlada; proceso linfoproliferativo. Tras valoración preanestésica se indicó cirugía valvular reparadora previa a la cirugía por cáncer de colon. La optimización preoperatoria mediante la cirugía cardiaca y el ajuste del tratamiento farmacológico, así como el apoyo en la monitorización hemodinámica para la toma de decisiones durante el periodo perioperatorio, mediante un dispositivo mínimamente invasivo (Vigileo®), fueron las claves en el correcto manejo de este paciente; combinamos raquianalgesia con morfina intratecal y anestesia general. El paciente se mantuvo estable con IC 2,3 - 3 l/min/m2, VVS 2 - 7% y ScvO2 74- 67%.Tras el éxito del proceso anestésico-quirúrgico concluimos que hoy en día tenemos la obligación de conocer y aplicar las recomendaciones disponibles en las guías elaboradas por las sociedades de anestesiología y cardiología, de forma conjunta, que se actualizan continuamente y permiten al clínico protocolizar la toma de decisiones basándose en la evidencia científica.AbstractPatients with valve disease are at a higher risk of perioperative complications in the context of non-cardiac surgery. The active involvement of the anaesthetist from the moment of the pre-anaesthesia assessment to determine the severity of the disease is crucial.The purpose of this report on the management of a clinical case is to highlight the need for a multidisciplinary approach to the patient with heart disease.We present the case of a patient in the eighth decade of life with severe aortic stenosis, and a 46mm infra-renal abdominal aortic aneurysm; chronic obstructive pulmonary disease, controlled arterial hypertension; and a lymphoproliferative process. Following the pre-anaesthesia assessment, valve repair surgery was indicated prior to a surgical procedure for colon cancer resection. Key to the successful management of this patient was pre-operative optimization with cardiac surgery and adjustment of the pharmacological treatment, plus haemodynamic monitoring as a basis for decision-making during the perioperative period using a minimally invasive device (Vigileo®). Spinal analgesia with intrathecal morphine was combined with general anaesthesia. The patient remained stable with CI 2.3 - 3 l/min/m2, SVV 2 - 7% and ScvO2 74- 67%.As a result of the successful anaesthetic and surgical process, we concluded that it is our duty at the present time to know and apply the recommendations contained in the guidelines developed by the anaesthesia and cardiology societies and their regular updates, as they allow clinicians to make decisions in accordance with evidence-based protocols
The race to target MET exon 14 skipping alterations in non-small cell lung cancer: The Why, the How, the Who, the Unknown, and the Inevitable
No full textAbstractA number of small molecule tyrosine kinase inhibitors (TKIs) have now been approved for the treatment of non-small cell lung cancers (NSCLC), including those targeted against epidermal growth factor receptor, anaplastic lymphoma kinase, and ROS1. Despite a wealth of agents developed to target the receptor tyrosine kinase, MET, clinical outcomes have as yet been disappointing, leading to pessimism about the role of MET in the pathogenesis of NSCLC. However, in recent years, there has been a renewed interest in MET exon 14 alterations as potential drivers of lung cancer.MET exon 14 alterations, which result in increased MET protein levels due to disrupted ubiquitin-mediated degradation, occur at a prevalence of around 3% in adenocarcinomas and around 2% in other lung neoplasms, making them attractive targets for the treatment of lung cancer. At least five MET-targeted TKIs, including crizotinib, cabozantinib, capmatinib, tepotinib, and glesatinib, are being investigated clinically for patients with MET exon 14 altered-NSCLC. A further two compounds have shown activity in preclinical models. In this article, we review the current clinical and preclinical data available for these TKIs, along with a number of other potential therapeutic options, including antibodies and immunotherapy. A number of questions remain unanswered regarding the future of MET TKIs, but unfortunately, the development of resistance to targeted therapies is inevitable. Resistance is expected to arise as a result of receptor tyrosine kinase mutation or from upregulation of MET ligand expression; potential strategies to overcome resistance are proposed
Optimally oriented grooves on dental implants improve bone quality around implants under repetitive mechanical loading
No full textAbstractThe aim was to investigate the effect of groove designs on bone quality under controlled-repetitive load conditions for optimizing dental implant design. Anodized Ti-6Al-4V alloy implants with −60° and +60° grooves around the neck were placed in the proximal tibial metaphysis of rabbits. The application of a repetitive mechanical load was initiated via the implants (50N, 3Hz, 1800 cycles, 2days/week) at 12weeks after surgery for 8weeks. Bone quality, defined as osteocyte density and degree of biological apatite (BAp) c-axis/collagen fibers, was then evaluated. Groove designs did not affect bone quality without mechanical loading; however, repetitive mechanical loading significantly increased bone-to-implant contact, bone mass, and bone mineral density (BMD). In +60° grooves, the BAp c-axis/collagen fibers preferentially aligned along the groove direction with mechanical loading. Moreover, osteocyte density was significantly higher both inside and in the adjacent region of the +60° grooves, but not −60° grooves. These results suggest that the +60° grooves successfully transmitted the load to the bone tissues surrounding implants through the grooves. An optimally oriented groove structure on the implant surface was shown to be a promising way for achieving bone tissue with appropriate bone quality. This is the first report to propose the optimal design of grooves on the necks of dental implants for improving bone quality parameters as well as BMD. The findings suggest that not only BMD, but also bone quality, could be a useful clinical parameter in implant dentistry.Statement of SignificanceAlthough the paradigm of bone quality has shifted from density-based assessments to structural evaluations of bone, clarifying bone quality based on structural bone evaluations remains challenging in implant dentistry. In this study, we firstly demonstrated that the optimal design of dental implant necks improved bone quality defined as osteocytes and the preferential alignment degree of biological apatite c-axis/collagen fibers using light microscopy, polarized light microscopy, and a microbeam X-ray diffractometer system, after application of controlled mechanical load. Our new findings suggest that bone quality around dental implants could become a new clinical parameter as well as bone mineral density in order to completely account for bone strength in implant dentistry
Sustainable crop intensification through surface water irrigation in Bangladesh? A geospatial assessment of landscape-scale production potential
No full textAbstractChanging dietary preferences and population growth in South Asia have resulted in increasing demand for wheat and maize, along side high and sustained demand for rice. In the highly productive northwestern Indo-Gangetic Plains of South Asia, farmers utilize groundwater irrigation to assure that at least two of these crops are sequenced on the same field within the same year. Such double cropping has had a significant and positive influence on regional agricultural productivity. But in the risk-prone and food insecure lower Eastern Indo-Gangetic Plains (EIGP), cropping is less intensive. During the dryer winter months, arable land is frequently fallowed or devoted to lower yielding rainfed legumes. Seeing opportunity to boost cereals production, particularly for rice, donors and land use policy makers have consequently reprioritized agricultural development investments in this impoverished region. Tapping groundwater for irrigation and intensified double cropping, however, is unlikely to be economically viable or environmentally sound in the EIGP. Constraints include saline shallow water tables and the prohibitively high installation and energetic extraction costs from deeper freshwater aquifers. The network of largely underutilized rivers and natural canals in the EIGP could conversely be tapped to provide less energetically and economically costly surface water irrigation (SWI). This approach is now championed by the Government of Bangladesh, which has requested USD 500 million from donors to implement land and water use policies to facilitate SWI and double cropping. Precise geospatial assessment of where freshwater flows are most prominent, or where viable fallow or low production intensity cropland is most common, however remains lacking. In response, we used remotely sensed data to identify agricultural land, detect the temporal availability of freshwater in rivers and canals, and assess crop production intensity over a three-year study period in a 33,750km2 case study area in southwestern Bangladesh. We combined these data with georeferenced and temporally explicitly soil and water salinity information, in addition to relative elevation classifications, in order to examine the extent of winter fallows and low productivity rainfed cropland that could be irrigated by small-scale surface water pumps. Applying observations of irrigated crop sowing dates and yields from 510 wheat, 550 maize, and 553 rice farmers, we also modeled crop intensification production scenarios within the case study area. We conservatively estimate that at least 20,800 and 103,000ha of fallow and rainfed cropland, respectively, could be brought into intensified double cropping using SWI. Scenario analysis indicates that if 25%–75% of the fallow or low-intensity land were converted to irrigated maize, national aggregate production could increase by 10–14% or 29–42%, respectively. Conversion to wheat would conversely boost national production by 9–10% or 26–31%. Irrigated rice is however unlikely to contribute >3%. In aggregate, these actions could generate between USD 36–108 million of revenue annually among farmers. Intensification therefore has important land use policy and food and income security implications, helping to rationalizei SWI investments. Crop choice, water resource allocation, and water governance will however remain crucial considerations for irrigation planners
Country specific predictions of the cost-effectiveness of malaria vaccine RTS,S/AS01 in endemic Africa
No full textAbstractBackgroundRTS,S/AS01 is a safe and moderately efficacious vaccine considered for implementation in endemic Africa. Model predictions of impact and cost-effectiveness of this new intervention could aid in country adoption decisions.MethodsThe impact of RTS,S was assessed in 43 countries using an ensemble of models of Plasmodium falciparum epidemiology. Informed by the 32months follow-up data from the phase 3 trial, vaccine effectiveness was evaluated at country levels of malaria parasite prevalence, coverage of control interventions and immunization. Benefits and costs of the program incremental to routine malaria control were evaluated for a four dose schedule: first dose administered at six months, second and third - before 9months, and fourth dose at 27months of age. Sensitivity analyses around vaccine properties, transmission, and economic inputs were conducted.ResultsIf implemented in all 43 countries the vaccine has the potential to avert 123 (117;129) million malaria episodes over the first 10years. Burden averted averages 18,413 (range of country median estimates 156–40,054) DALYs per 100,000 fully vaccinated children with much variation across settings primarily driven by differences in transmission intensity. At a price of 39.8 per fully vaccinated child with a median cost-effectiveness ratio of 78–136 (range 220) - in settings where parasite prevalence in children aged 2–10years is at or above 10%.ConclusionRTS,S/AS01has the potential to substantially reduce malaria burden in children across Africa. Conditional on assumptions on price, coverage, and vaccine properties, adding RTS,S to routine malaria control interventions would be highly cost-effective. Implementation decisions will need to further consider feasibility of scaling up existing control programs, and operational constraints in reaching children at risk with the schedule
Comparative study of N-[(4-methoxyphenyl) (morpholin-4-yl)methyl]acetamide (MMPA) and N-[morpholin-4-yl(phenyl)methyl]acetamide (MPA) as corrosion inhibitors for mild steel in sulfuric acid solution
No full textAbstractTwo Mannich bases namely, N-[(4-methoxyphenyl)(morpholin-4-yl)methyl]acetamide (MMPA) and N-[morpholin-4-yl(phenyl)methyl]acetamide (MPA) were synthesized and their influence on the inhibition of corrosion of mild steel in 1.0M H2SO4 was investigated by weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and FT-IR spectroscopy. The weight loss measurements showed that these inhibitors have excellent inhibiting effect at a concentration of 0.01M. The inhibitor efficiency was found to depend on both concentration and molecular structure of the inhibitor. Both the compounds have been found to be relatively good inhibitors. Potentiodynamic polarization curves revealed that the studied inhibitors represent a mixed-type, predominantly cathodic control. An equivalent circuit is suggested based on an analysis of EIS data. The negative value of standard free energy of adsorption in the presence of inhibitor suggests spontaneous adsorption of inhibitors on the mild steel surface. The activation energy of corrosion and other thermodynamic parameters were calculated to elaborate the mechanism of corrosion inhibition. The Temkin isotherm was found to provide an accurate description of the adsorption behavior of the inhibitors. Surface analysis using scanning electron microscope (SEM) shows a significant morphological improvement on the mild steel surface with the addition of inhibitors. FT-IR spectra revealed the interaction between inhibitor molecules and mild steel surface
Risk and preventive factors for prostate cancer in Japan: The Japan Public Health Center-based prospective (JPHC) study
No full textAbstractThe incidence of prostate cancer is much lower in Asian than in Western populations. Lifestyle and dietary habits may play a major role in the etiology of this cancer. Given the possibility that risk factors for prostate cancer differ by disease aggressiveness, and the fact that 5-year relative survival rate of localized prostate cancer is 100%, identifying preventive factors against advanced prostate cancer is an important goal.Using data from the Japan Public Health Center-based Prospective Study, the author elucidates various lifestyle risk factors for prostate cancer among Japanese men. The results show that abstinence from alcohol and tobacco might be important factors in the prevention of advanced prostate cancer. Moreover, the isoflavones and green tea intake in the typical Japanese diet may decrease the risk of localized and advanced prostate cancers, respectively
The role of adult neurogenesis in psychiatric and cognitive disorders
No full textAbstractNeurogenesis in mammals occurs throughout life in two brain regions: the ventricular–subventricular zone (V–SVZ) and the subgranular zone (SGZ) of the hippocampal dentate gyrus. Development and regulation of the V–SVZ and SGZ is unique to each brain region, but with several similar characteristics. Alterations to the production of new neurons in neurogenic regions have been linked to psychiatric and neurodegenerative disorders. Decline in neurogenesis in the SGZ correlates with affective and psychiatric disorders, and can be reversed by antidepressant and antipsychotic drugs. Likewise, neurogenesis in the V–SVZ can also be enhanced by antidepressant drugs. The regulation of neurogenesis by neurotransmitters, particularly monoamines, in both regions suggests that aberrant neurotransmitter signaling observed in psychiatric disease may play a role in the pathology of these mental health disorders. Similarly, the cognitive deficits that accompany neurodegenerative disease may also be exacerbated by decreased neurogenesis. This review explores the regulation and function of neural stem cells in rodents and humans, and the involvement of factors that contribute to psychiatric and cognitive deficits.This article is part of a Special Issue entitled SI:StemsCellsinPsychiatry
A rapid stability indicating LC-method for determination of praziquantel in presence of its pharmacopoeial impurities
No full textAbstractThis study reports for the first time about a stability indicating RP-HPLC method for quantitative determination of Praziquantel (PZQ) in bulk powder and dosage form and in presence of its pharmacopoeial impurities. The chromatographic separation was carried out on (Caltrex AI®) calixarene column, a relatively new packing material. Chromatography was done using an isocratic binary mobile phase consisting of ACN and 25mM ammonium acetate (NH4Ac) in the ratio of 40:60 at flow rate of 1mLmin−1, 30°C and 210nm wavelength for detection. The elution time of PZQ was found to be 6.15±0.03min. The method was validated for system suitability, linearity, precision, limits of detection and quantitation, specificity, stability and robustness. The robustness study was done for small changes in temperature, flow rate, wavelength of detection and % of ACN in mobile phase. Stability tests were done through exposure of the analyte solution to five different stress conditions: Reflux with 1N HCl, reflux with 1N NaOH, reflux with 30% H2O2, thermal degradation of powder and exposure to UV radiation. Limits of detection and quantification were found to be 0.56 and 1.70μgmL−1, respectively. The recovery value of this method was 100.30%±1.10 and the reproducibility was within 1.31
Conservation Reserve Program mitigates grassland loss in the lesser prairie-chicken range of Kansas
No full textAbstractSince the beginning of the 20th century, the overall occupied range of the lesser prairie-chicken (Tympanuchus pallidicinctus) has declined by 84% commensurate with population trends. Much of this decline has been attributed to the loss and fragmentation of native grasslands throughout the lesser prairie-chicken range. However, quantification of changes in land cover in the distribution of the lesser prairie-chicken is lacking. Our objectives were to (1) document changes in the areal extent and connectivity of grasslands in the identified lesser prairie-chicken range in Kansas, USA, (>60% of extant lesser prairie-chicken population) from the 1950s to 2013 using remotely sensed data and (2) assess the potential of the Conservation Reserve Program (U.S. Department of Agriculture Program converting cropland to permanent cover; CRP) to mitigate grassland loss. Digital land cover maps were generated on a decadal time step through spectral classification of LANDSAT images and visual analysis of aerial photographs (1950s and 1960s). Landscape composition and configuration were assessed using FRAGSTATS to compute a variety of landscape metrics measuring changes in the amount of grassland present as well as changes in the size and configuration of grassland patches. With the exception of a single regional portion of the range, nearly all of the grassland converted to cropland in the lesser prairie-chicken range of Kansas occurred prior to the 1950s. Prior to the implementation of CRP, the amount of grassland decreased 3.6% between the 1950s and 1985 from 18,455 km2 to 17,788 km2. Since 1985, the overall amount of grassland in the lesser prairie-chicken range has increased 11.9% to 19,898 km2 due to implementation of CRP, although the area of grassland decreased between 1994 and 2013 as CRP contracts were not renewed by landowners. Since 1986 grassland in Kansas became more connected and less fragmented in response to the CRP. While the CRP has been successful in increasing grassland quantity and connectivity throughout the lesser prairie-chicken range in Kansas, offsetting loss of grassland since the 1950s, abundance and occupied range of lesser prairie-chickens has declined since the 1980s, suggesting that habitat quality is the principal factor influencing population demography of the species. Although the CRP is contributing to conservation actions for lesser prairie-chickens, efforts to improve habitat quality throughout the range of the lesser prairie-chicken are likely necessary to meet management goals. Continuation of the CRP faces an uncertain future in the face of rising commodity prices, energy development, and reduction in program scope, leaving open the possibility that these areas that have created habitat for lesser prairie-chickens could be lost