Increase in the Bioactive Potential of Olive Pomace Oil after Ultrasound-Assisted Maceration.

Olive pomace oil is obtained when a mixture of olive pomace and residual water is subjected to a second centrifugation. This oil has small amounts of phenolic and volatile compounds compared with extra-virgin olive oil. This study aimed to promote the aromatization of olive pomace oil with rosemary and basil using ultrasound-assisted maceration (UAM) to increase its bioactive potential. For each spice, the ultrasound operating conditions (amplitude, temperature, and extraction time) were optimized through central composite designs. Free fatty acids, peroxide value, volatile compounds, specific extinction coefficients, fatty acids, total phenolic compounds, antioxidant capacity, polar compounds, and oxidative stability were determined. After obtaining the optimal maceration conditions assisted by ultrasound, pomace oils flavored with rosemary and basil were compared to pure olive pomace oil. Quality parameters and fatty acids showed no significant difference after UAM. Rosemary aromatization by UAM resulted in a 19.2-fold increase in total phenolic compounds and a 6-fold increase in antioxidant capacity, in addition to providing the most significant increase in oxidative stability. Given this, aromatization by ultrasound-assisted maceration is an efficient method to increase, in a short time, the bioactive potential of olive pomace oil.

Mental illness attitudes in medical education: Assessing the stigma in medical students / Actitudes hacia los trastornos mentales en la educación médica: evaluando el estigma en estudiantes médicos

Abstract Introduction Factors affecting the quality of physician care include a shortage of trained staff, stigma, and discrimination. Objective The objective was to compare the intensity of stigmatization before and after a Psychiatry course, as measured by the scale of clinicians' attitudes towards mental illness, a version for medical students (MICA-2) designed to identify stigmatic attitudes towards mental disorders. Method The fifth-year Medicine students enrolled in the Psychiatry course answered anonymously using the MICA-2 test at the start and the end of their course. Additionally, we asked the students to answer a question about their interest in learning more about mental illness. Results Three hundred and thirty students were invited; 300 agreed to participate in the first application of the scales, and 291 in the follow-up. The average age was 22 ± 2 years, with a range of 20-30 years, and there was a similar gender distribution in both applications. In the initial application, the average score of the MICA-2 was 41.34 (SD = 7.86, 95% CI = [40.43, 42.25]). The follow-up application's mean was 37.10 (SD = 8.15, 95% CI = [36.30, 38.15]). Also, there was a decrease in interest in learning more about mental illness. Discussion and conclusion A reduction in the average scores of the MICA-2 was observed after a Psychiatry course, suggesting that attitudes toward mental disorders improved. A Psychiatry clerkship with close supervision modified the attitudes of medical students toward mental disorders. However, it did not increase their interest in learning more about mental illness.

Resumen Introducción Los factores que afectan la calidad de la atención médica incluyen: la escasez de personal capacitado, el estigma y la discriminación. Objetivo El objetivo fue comparar la intensidad de la estigmatización antes y después del curso de Psiquiatría, se utilizó la escala de las actitudes de los clínicos hacia la enfermedad mental, versión para estudiantes médicos (MICA-2), diseñada para identificar actitudes estigmatizantes hacia los trastornos mentales. Método Los estudiantes médicos de quinto año que tomaban el curso de Psiquiatría respondieron de forma anónima la escala MICA-2 al inicio y al final del curso. Además, se les preguntó sobre su interés en aprender más sobre los trastornos mentales. Resultados Se invitaron a 330 estudiantes; 300 aceptaron participar en la primera aplicación de las escalas y 291 en el seguimiento. La edad promedio fue de 22 ± 2 años, con un rango de 20-30 años; con una distribución de género similar en ambas aplicaciones. En la aplicación inicial, la puntuación media del MICA-2 fue de 41.34 (DE = 7.86, IC 95% = [40.43, 42.25]). En la de seguimiento, la media fue de 37.10 (DE = 8.15, IC 95% = [36.30, 38.15]). El interés en aprender más sobre los trastornos mentales disminuyó. Discusión y conclusión Observamos una reducción en los puntajes promedio después de tomar el curso de Psiquiatría, lo que sugiere que las actitudes hacia los trastornos mentales mejoraron. Un curso de Psiquiatría con mayor disposición y supervisión estrecha modificó las actitudes hacia los trastornos mentales de los estudiantes médicos, pero su interés en aprender más sobre los trastornos mentales disminuyó.

Guided growth: indications and techniques for correction of knock knees and bowlegs.

PURPOSE OF REVIEW: Lower extremities axis alterations are a frequent cause for consultation in the medical practice of the care of paediatric patients. When it corresponds to pathological situations, guided growth surgery has been positioned as a possibility of well tolerated, reproducible and predictable resolution. For this reason, its use has increased significantly in recent years. In this review, its current indications, preoperative study, results and complications described in the updated literature will be discussed. RECENT FINDINGS: The success of the technique remains high in the current literature, expanding the technique to other segments and disorders, and describing new ways of performing tension band with sutures. In addition, there is an increase in its incidence and a decrease in the associated hospitalized days, which can associate with techniques of lower morbidity. SUMMARY: As guided growth surgery allows for successful correction of axis alterations, to achieve this, it is important to know the main indications, preoperative analysis and theoretical bases on which this technique is based, to carry it out in an adequate and timely manner, seeking an adequate resolution of the child's problem.

MicroRNAs and their role in the malignant transformation of oral leukoplakia: a scoping review

Background: MiRNAs are small non-coding RNAs that regulate gene expression at the post-transcriptional level and have been associated with malignant transformation of oral epithelial precursor lesions such as oral leukoplakia. The aim was to perform a scoping review of the contemporary literature about the different roles of miRNAs during the malignant transformation of oral leukoplakia. Material and Methods: We conducted a systematic search with the following MeSH terms: ‘oral leukoplakia’, ‘carcinoma in situ’, ‘microRNAs’, ‘mouth neoplasms’ and ‘epithelial–mesenchymal transition’ in PubMed/MEDLINE, EMBASE and SpringerLink. Results: Fifteen articles were included for analysis, among which in vivo and in vitro articles were included. A total of 21 different miRNAs were found to be involved in the malignant transformation process of oral leukoplakia. Regarding their possible effects, 6 miRNAs were classified as oncogenic, 5 as tumour suppressors and 10 were related to epithelial–mesenchymal transition, invasion and migration. Conclusions: Based on the current review, we concluded that miRNAs-21, 345, 181-b and 31* seem to be potential markers of malignant transformation of oral leukoplakia. However, further clinical prospective studies are needed in order to validate their utility as prognostic biomarkers.(AU)

Micronization increases the bioaccessibility of polyphenols from granulometrically separated olive pomace fractions.

The effect of micronization of granulometrically fractionated olive pomace (OP) on the bioaccessibility of polyphenols and the antioxidant capacity was investigated during sequential in vitro static digestion. Crude OP was fractionated in a 2-mm sieve (F1: > 2 mm; F2: < 2 mm) and then micronized (300 r min-1, 5 h) generating F1AG (17.8 µm) and F2AG (15.6 µm). Micronization increased the release of hydroxytyrosol, oleuropein, caffeic acid, and decarboxymethyl oleuropein aglycone (3,4-DHPEA-EDA) in the salivary and gastric phase, beyond luteolin in the gastric phase. Micronization also increased the intestinal bioaccessibility of hydroxytyrosol, 3,4-DHPEA-EDA, oleuropein, luteolin, and apigenin; it was more effective for F2AG than F1AG. Micronized samples increased antioxidant capacity in the gastric phase. F2AG exhibited the highest antioxidant capacity in the insoluble intestinal fraction. Thus, micronization can be further exploited to improve the nutraceutical properties of OP by increasing the bioaccessibility and antioxidant capacity of phenolic compounds.

Ultrasound assisted maceration for improving the aromatization of extra-virgin olive oil with rosemary and basil.

Aromatization of extra-virgin olive oil (EVOO) with aromatic plants is commonly used to enrich the oil with aromatic and antioxidant compounds. Ultrasound can be an alternative to accelerate this process. The objective of this work was to determine if ultrasound is able to accelerate EVOO aromatization with rosemary and basil and how it affects the migration of volatile and other compounds, the oxidative stability and the antioxidant capacity of the aromatized products. Ultrasound parameters (amplitude, time, and temperature of extraction) were optimized for each herb with central composite designs. Free fatty acid, peroxide value, K232, K270, ΔK, fatty acid profile, total phenolics, antioxidant capacity, polar compounds, oxidative stability and volatile compounds profile were evaluated in all samples. Physical effects of ultrasound on the herbs were observed by scanning electron microscopy. In the optimization, variables related to the oxidative processes were minimized and compounds migration and oxidative stability were maximized. Results were 70.09% amplitude, 36.6 min and 35 °C for rosemary and 95.98% amplitude, 9.9 min and 30 °C for basil. These conditions were compared to 7 and 15 days of conventional maceration (CM). Aromatization of EVOO with rosemary, both by ultrasound assisted maceration (UAM) or CM, improved total phenolics, terpenes, esters, ketones, stability and induction times, as well as decreased the values for the quality parameters. The use of UAM accelerated the process to 37 min. However, aromatization with basil by CM increased the values for the quality parameters and reduced the total phenolics, the antioxidant capacity and the induction and stability times. UAM with basil reached better results than those observed for CM, in only 10 min. In conclusion, rosemary is more appropriate than basil for EVOO aromatization, and UAM was the best choice to accelerate the processes when compared to CM.

Measurement properties from the Brazilian Portuguese version of the QUIP-RS.

Parkinson's disease (PD) has numerous motor and non-motor symptoms. Among non-motor manifestations impulse control disorders (ICDs) stand out. ICDs include compulsions for gambling, shopping, eating, and sexual behavior, and "related disorders" such as hobbyism, simple motor activities, and dopamine dysregulation syndrome. There is no rating scale translated and adapted transculturally into Brazilian Portuguese language. Therefore, we cross-culturally adapted and investigated the measurement properties of the Brazilian version of the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS). Fifty-three patients participated in the study. Inter-evaluator and test-retest (patient and health professional) reliabilities (intraclass correlation coefficient) were all excellent (0.93, 0.93, and 0.99). The internal consistency was high (α = 0.92). The Minimal detectable change (MDC) value was 5.8 (patient) and 2.3 (health professional) points. There was a floor, but no ceiling, effect. In summary, the Brazilian version of the QUIP-RS has high reliability and content validity.

Respiratory syncytial virus acute respiratory infection-associated hospitalizations in preterm Mexican infants: A cohort study.

BACKGROUND: Respiratory syncytial virus (RSV) is the leading cause of severe acute respiratory infections (ARI) in preterm infants. The incidence of RSV-associated hospitalizations has not been defined in Mexico. OBJECTIVES: To determine the incidence of ARI- and RSV-associated hospitalizations in preterm infants during the first year of life. METHODS: Prospective cohort study of 294 preterm infants followed up through monthly telephone calls and routine outpatient visits. Hospitalized children were identified through daily visits to pediatric wards of participating hospitals and through telephone calls. Respiratory samples were tested for RSV by RT-PCR. RESULTS: Mean gestational age of participating infants was 33 weeks. Ninety-six infants were diagnosed with bronchopulmonary dysplasia (BPD) and 17 with congenital heart disease (CHD); 11 had both conditions. There were 71 hospitalization episodes in 53 infants. Respiratory samples for RSV detection were available in 44 hospitalization episodes, and the result was positive in 16 (36.3%). At least one hospitalization for ARI was recorded in 33 of 96 participants with BPD, in seven of 17 with CHD, and 18 of 192 infants without these diagnoses. Five (71.4%) of CHD infants who required admission also had BPD. RSV-confirmed hospitalization rates were 9.4%, 5.9%, and 2.6% for infants with BPD, CHD, and otherwise healthy preterm infants, respectively. Attributable RSV admission frequencies were estimated to be 13.6%, 16.5%, and 4.1%, respectively. CONCLUSIONS: Mexican preterm infants, particularly those with BPD, have high rates of ARI- and RSVassociated hospitalizations. Specific interventions to reduce the incidence of severe infections in this highrisk group are required.

Sixty-Day Mortality Among 520 Italian Hospitalized COVID-19 Patients According to the Adopted Ventilatory Strategy in the Context of an Integrated Multidisciplinary Clinical Organization: A Population-Based Cohort Study.

PURPOSE: Although the decision of which ventilation strategy to adopt in COVID-19 patients is crucial, yet the most appropriate means of carrying out this undertaking is not supported by strong evidence. We therefore described the organization of a province-level healthcare system during the occurrence of the COVID-19 epidemic and the 60-day outcomes of the hospitalized COVID-19 patients according to the respiratory strategy adopted given the limited available resources. PATIENTS AND METHODS: All COVID-19 patients (26/02/2020-18/04/2020) in the Rimini Province of Italy were included in this population-based cohort study. The hospitalized patients were classified according to the maximum level of respiratory support: oxygen supplementation (Oxygen group), non-invasive ventilation (NIV-only group), invasive mechanical ventilation (IMV-only group), and IMV after an NIV trial (IMV-after-NIV group). Sixty-day mortality risk was estimated with a Cox proportional hazard analysis adjusted by age, sex, and administration of steroids, canakinumab, and tocilizumab. RESULTS: We identified a total of 1,424 symptomatic patients: 520 (36.5%) were hospitalized, while 904 (63.5%) were treated at home with no 60-day deaths. Based on the respiratory support, 408 (78.5%) were assigned to the Oxygen group, 46 (8.8%) to the NIV-only group, 25 (4.8%) to the IMV-after-NIV group, and 41 (7.9%) to the IMV-only group. There was no significant difference in the PaO2/FiO2 at IMV inception in the IMV-after-NIV and IMV-only groups (p=0.9). Overall 60-day mortality was 24.2% (Oxygen: 23.0%; NIV-only: 19.6%; IMV-after-NIV: 32.0%; IMV-only: 36.6%; p=0.165). Compared with the Oxygen group, the adjusted 60-day mortality risk significantly increased in the IMV-after-NIV (HR 2.776; p=0.024) and IMV-only groups (HR 2.966; p=0.001). CONCLUSION: This study provided a population-based estimate of the impact of the COVID-19 outbreak in a severely affected Italian province. A similar 60-day mortality risk was found for patients undergoing immediate IMV and those intubated after an NIV trial with favorable outcomes after prolonged IMV.

Gelatinasas como marcadores de consumo crónico de alcohol: un estudio piloto en Uruguay / Gelatinases as markers of chronic alcohol consumption: a pilot study in Uruguay / Gelatinasas como marcadores de consumo crônico de álcool: um estúdio piloto em Uruguai

El consumo crónico de alcohol en Uruguay es un problema creciente, sin embargo, las determinaciones de biomarcadores consensuados no se realizan sistemáticamente ni se investigan otros marcadores potenciales. Para validar la hipótesis de que las metaloproteinasas de matriz con actividad gelatinasa son biomarcadores de consumo crónico de alcohol, se evaluaron muestras de sangre de 100 alcohólicos que comenzaron a atenderse en la Unidad de Trastornos Relacionados con el Alcohol y de 50 donantes sanos no alcohólicos. Las muestras de alcohólicos presentaron actividad de gelatinasas que triplicaron la de los controles y aumentos pequeños pero significativos en los niveles de γ-glutamil transferasa, aspartato-aminotransferasa y volumen corpuscular medio. Los valores de transferrina deficiente en carbohidratos fueron menores en alcohólicos que en controles. Estos resultados permiten proponer a las gelatinasas como los indicadores más sensibles del consumo sostenido de alcohol en la población analizada, ya que las enzimas hepáticas y el volumen corpuscular medio muestran una tendencia acorde con la literatura pero no alcanzaron valores asociados a la patología. Dado que la transferrina deficiente en carbohidratos es considerada el biomarcador indirecto más sensible y específico de consumo crónico de alcohol, los valores menores obtenidos en alcohólicos respecto de controles sugieren problemas metodológicos que podrían subsanarse aplicando otras técnicas de medida o por la presencia de interferencias que deben ser identificadas. Finalmente, estos hallazgos justifican una extensión de este trabajo piloto, así como estudios adicionales centrados en la participación de las metaloproteinasas de matriz con actividad gelatinasa en las cascadas de daño asociadas al consumo crónico de alcohol.

Chronic alcohol consumption in Uruguay is a growing problem, however, determinations of consensual biomarker are not performed systematically neither potential markers are explored. To validate the hypothesis that matrix metalloproteinases with gelatinase activity are biomarkers of chronic alcohol consumption, blood samples of 100 alcoholics that began medical treatment at the Unidad de Trastornos Relacionados con el Alcohol and 50 healthy non-alcoholic donors were evaluated. Alcoholic samples showed gelatinase activity that tripled that of controls and small but significant increases in levels of γ-glutamyl transferase, aspartate-aminotransferase and mean cellular volume. Carbohydrate deficient transferrin values were lower in alcoholics than in controls. These results allow proposing gelatinases as the most sensitive indicators of sustained alcohol consumption in the population analyzed since hepatic enzymes and mean cellular volume showed a tendency consistent with the literature but did not reach values associated with the pathology. Since carbohydrate-deficient transferrin is considered the most sensitive and specific indirect biomarker of chronic alcohol consumption, lower values in alcoholics related to controls suggest methodological problems that could be solved by applying other measurement techniques or by the presence of yet unknown interferences. Finally, these findings justify an extension of this pilot work, as well as additional studies focused on the participation of matrix metalloproteinases with gelatinase activity in the cascades of damage associated with chronic alcohol consumption.

O consumo crônico de álcool no Uruguai é um problema crescente, no entanto, as determinações consensuais de biomarcadores não são realizadas sistematicamente ou os potenciais marcadores são explorados. Para validar a hipótese de que as metaloproteinases de matriz com atividade gelatinase são biomarcadores do consumo crônico de álcool, foram avaliadas amostras de sangue cd 100 alcoólatras que começaram a ser tratadas na Unidad de Trastornos Relacionados con el Alcohol e 50 doadores não-alcoólatras saudáveis. As amostras alcoólicas apresentaram atividade de gelatinase que triplicou a dos controles e pequenos más significativos aumentos nos níveis de γ-glutamil transferase, aspartato-aminotransferase e volume médio celular. Os valores de transferrina deficientes em carboidratos foram menores nos alcoolistas que nos controles. Esses resultados permitem que as gelatinases sejam propostas como os indicadores mais sensíveis do consumo sustentado de álcool na população analisada, uma vez que as enzimas hepáticas e o volume celular médio apresentam uma tendência consistente com a literatura, mas não alcançaram valores associados à patologia. Como a transferrina deficiente em carboidratos é considerada o biomarcador indireto mais sensível e específico do consumo crônico de álcool, os valores mais baixos em alcoólatras do que em controles sugerem problemas metodológicos que poderiam ser sanados pela aplicação de outras técnicas de mensuração pela presença de interferências que deben ser identificadas. Finalmente, esses achados justificam uma extensão deste trabalho piloto, bem como estudos adicionais voltados para a participação de metaloproteinases de matriz com atividade de gelatinase nas cascatas de danos associados ao consumo crônico de álcool.

Examining the Impact of This Is My Brave on Mental Illness Stigma and Willingness to Seek Help: A Pilot Study.

This Is My Brave (TIMB) is a contact-based mental illness stigma reduction program, set in theaters, meant to reduce stigma, increase beliefs about empowerment and recovery, and improve attitudes towards treatment seeking for mental health concerns. The authors conducted the first empirical evaluation of TIMB using a pre-post survey design. Approximately 481 audience members of TIMB performances were invited to complete a survey of stigmatizing attitudes towards mental illness, beliefs about recovery and empowerment, and willingness to seek treatment at pre-and post-performance. Analyses of responses from 372 participants using paired samples t-tests revealed changes in the desired direction on all variables from pre-test to post-test. Audience members experienced a decrease in stigma, improvements in beliefs about recovery and empowerment, and greater willingness to seek treatment. TIMB is a promising stigma-reduction program and there is a need for a more detailed investigation of the program's impact using more rigorous methodology.

Non-epileptic myoclonic attacks in infancy: three cases.

Since the first cases of abnormal paroxystic movements in normal infants were described, the importance of accurate characterization of this medical condition has been increasingly confirmed in the literature. Non-epileptic attacks mimic epileptic paroxysms in clinical presentation, but they have a typically benign course and are unresponsive to pharmacological treatment. An evident feature of the syndrome is its extreme variability in clinical manifestation. Here, we describe three normal infants with two similar forms of non-epileptic paroxysms. Electroclinical manifestations and profile of evolution were investigated. Ictal video-EEG polygraphic recordings were obtained for each patient. The increasing number of such reported clinical cases in the literature may contribute to high quality systematic reviews and the development of useful guidelines in the future. The clinical heterogeneity of non-epileptic attacks, together with the relative rarity of the condition, may make differential diagnosis with epileptic attacks very challenging. [Published with video sequences].

Thermal plasticity in Drosophila melanogaster: a comparison of geographic populations.

BACKGROUND: Populations of Drosophila melanogaster show differences in many morphometrical traits according to their geographic origin. Despite the widespread occurrence of these differences in more than one Drosophila species, the actual selective mechanisms controlling the genetic basis of such variation are not fully understood. Thermal selection is considered to be the most likely cause explaining these differences. RESULTS: In our work, we investigated several life history traits (body size, duration of development, preadult survival, longevity and productivity) in two tropical and two temperate natural populations of D. melanogaster recently collected, and in a temperate population maintained for twelve years at the constant temperature of 18 degrees C in the laboratory. In order to characterise the plasticity of these life history traits, the populations were grown at 12, 18, 28 and 31.2 degrees C. Productivity was the fitness trait that showed clearly adaptive differences between latitudinal populations: tropical flies did better in the heat but worse in the cold environments with respect to temperate flies. Differences for the plasticity of other life history traits investigated between tropical and temperate populations were also found. The differences were particularly evident at stressful temperatures (12 and 31.2 degrees C). CONCLUSION: Our results evidence a better cold tolerance in temperate populations that seems to have been evolved during the colonisation of temperate countries by D. melanogaster Afrotropical ancestors, and support the hypothesis of an adaptive response of plasticity to the experienced environment.

Developmental instability of the Drosophila wing as an index of genomic perturbation and altered cell proliferation.

We experimentally induced different levels of instability affecting the development of specific wing regions of Drosophila melanogaster using the UAS-GAL4 system. A common index of developmental instability is fluctuating asymmetry (FA), that is, random differences between body sides of single individuals. We studied the FA in transgenic strains carrying random genomic insertions (UAS strains), as well as insertions in the regulatory region of genes involved in the organization of wing development (GAL4 strains). In addition, the expression of genes that increase (dp110 and 3622) or decrease (dPTEN) cell proliferation was ectopically induced. Our results are related to different levels of perturbation. Through the first kind of perturbation, genome integrity was compromised by the insertion of foreign DNA. In all cases, we observed a general increase in FA, although it was rarely found significant. The second kind of perturbation involved a modification of genes controlling wing development through the insertion of a GAL4 sequence in their promoter region. The third kind involved the ectopic expression of genes controlling cell proliferation. Our results show that (i) the level of FA is connected with the level of morphological perturbation induced, (ii) FA increase was higher in the wing regions that were the target of the genetic perturbation, and (iii) developmental instability was also observed in regions that were not directly addressed by the perturbation. The results were discussed on the basis of the running models about Drosophila wing development.

The tumor suppressor gene fat modulates the EGFR-mediated proliferation control in the imaginal tissues of Drosophila melanogaster.

Molecules involved in cell adhesion can regulate both early signal transduction events, triggered by soluble factors, and downstream events involved in cell cycle progression. Correct integration of these signals allows appropriate cellular growth, differentiation and ultimately tissue morphogenesis, but incorrect interpretation contributes to pathologies such as tumor growth. The Fat cadherin is a tumor suppressor protein required in Drosophila for epithelial morphogenesis, proliferation control and epithelial planar polarization, and its loss results in a hyperplastic growth of imaginal tissues. While several molecular events have been characterized through which fat participates in the establishment of the epithelial planar polarity, little is known about mechanisms underlying fat-mediated control of cell proliferation. Here we provide evidence that fat specifically cooperates with the epidermal growth factor receptor (EGFR) pathway in controlling cell proliferation in developing imaginal epithelia. Hyperplastic larval and adult fat structures indeed undergo an amazing, synergistic enlargement following to EGFR oversignalling. We further show that such a strong functional interaction occurs downstream of MAPK activation through the transcriptional regulation of genes involved in the EGFR nuclear signalling. Considering that fat mutation shows di per se a hyperplastic phenotype, we suggest a model in which fat acts in parallel to EGFR pathway in transducing different cell communication signals; furthermore its function is requested downstream of MAPK for a correct rendering of the growth signals converging to the epidermal growth factor receptor.

Avalição de viabilidade miocárdica por técnicas com radionuclídeos / Avalição of myocardial viability by Radionuclide procedures

A doença arterial coronária é a principal causa de disfunção ventricular, não sendo esta necessariamente um processo irreversível.

CHROMOSOMAL ANALYSIS OF HEAT-SHOCK TOLERANCE IN DROSOPHILA MELANOGASTER EVOLVING AT DIFFERENT TEMPERATURES IN THE LABORATORY.

We investigated the heat tolerance of adults of three replicated lines of Drosophila melanogaster that have been evolving independently by laboratory natural selection for 15 yr at "nonextreme" temperatures (18°C, 25°C, or 28°C). These lines are known to have diverged in body size and in the thermal dependence of several life-history traits. Here we show that they differ also in tolerance of extreme high temperature as well as in induced thermotolerance ("heat hardening"). For example, the 28°C flies had the highest probability of surviving a heat shock, whereas the 18°C flies generally had the lowest probability. A short heat pretreatment increased the heat tolerance of the 18°C and 25°C lines, and the threshold temperature necessary to induce thermotolerance was lower for the 18°C line than for the 25°C line. However, neither heat pretreatment nor acclimation to different temperatures influenced heat tolerance of the 28°C line, suggesting the loss of capacity for induced thermotolerance and for acclimation. Thus, patterns of tolerance of extreme heat, of acclimation, and of induced thermotolerance have evolved as correlated responses to natural selection at nonextreme temperatures. A genetic analysis of heat tolerance of a representative replicate population each from the 18°C and 28°C lines indicates that chromosomes 1, 2, and 3 have significant effects on heat tolerance. However, the cytoplasm has little influence, contrary to findings in an earlier study of other stocks that had been evolving for 7 yr at 14°C versus 25°C. Because genes for heat stress proteins (hsps) are concentrated on chromosome 3, the potential role of hsps in the heat tolerance and of induced thermotolerance in these naturally selected lines is currently unclear. In any case, species of Drosophila possess considerable genetic variation in thermal sensitivity and thus have the potential to evolve rapidly in response to climate change; but predicting that response may be difficult.