Radioprotective effect of chloropyllin, protoporphyrin-IX and bilirubin compared with amifostine® in Drosophila melanogaster.

The identification of substances that prevent or minimize the detrimental effects of ionizing radiation is an essential undertaking. The aim of this paper was to evaluate and compare the radioprotective potential of chlorophyllin, protoporphyrin and bilirubin, with amifostine®, an US Food & Drug Administration approved radioprotector Using the somatic mutation and recombination assay in the Drosophila melanogaster wing, it was found that pretreatment (1-9 h) with any of the porphyrins or amifostine® alone, did not affect the larva-adult viability or the basal frequency of mutation. However, they were associated with significant reductions in frequency of somatic mutation and recombination compared with the gamma-irradiated (20 Gy) control as follows: bilirubin (69.3 %)> chlorophyllin (40.0 %)> protoporphyrin (39.0 %)> amifostine® (19.7 %). Bilirubin also caused a 16 % increase in larva-adult viability with 3 h of pretreatment respect to percentage induced in 20 Gy control group. Whilst amifostine® was associated with lower genetic damage after pre-treatment of 1 and 3 h, this did not attain significance. These findings suggest that the tested porphyrins may have some potential as radioprotectant agents.

O método em Marx: a determinação ontológica da realidade social / The method in Marx: the ontological determination of social reality

Resumo: O objetivo deste estudo foi discutir o método materialista histórico dialético, apontando elementos essenciais presentes no percurso metodológico. O método em Marx é um movimento dialético que parte da sua concepção ontológica da realidade social, em que o ser social produz suas próprias condições objetivas e subjetivas de existência e, por isso, teoria, método e concreto social constituem uma unidade metodológica.

Abstract: The objective of this study was to discuss the dialectical historical materialist method, pointing out essential elements present in the methodological course. The method in Marx is a dialectical movement that starts from its ontological conception of social reality, in which the social being produces its own objective and subjective conditions of existence and, therefore, theory, method and social concrete constitute a methodological unit.

Simultaneous TAPP inguinal repair and laparoscopic cholecystectomy: results of a case series.

BACKGROUND: Cholecystectomy and inguinal hernioplasty are the most frequent surgeries in Chile and the world. Laparoscopic inguinal hernioplasty, being a clean surgery, reports mesh infection rates of less than 2% and adding a simultaneous laparoscopic cholecystectomy is controversial due to an increase in the risk of mesh infection. The aim of this paper is to report the results of simultaneous TAPP hernioplasty with laparoscopic cholecystectomy. METHOD: Retrospective analysis of the digestive surgery database. We identified cases in which laparoscopic inguinal TAPP repair and simultaneous laparoscopic cholecystectomy were performed. Demographic, clinical information, hernia type and size, data from the surgery and its complications were also retrieved and analyzed. RESULTS: We identified 21 patients, 86% male and with an average age of 61 years range 46-84. 72% of the hernias were unilateral, predominating indirect 50%, direct 28% and the remaining were femoral and mixed. The average hernia size was 2.2 cm. The meshes used were 56% polypropylene, 37% polyester and 5% PVDF. We report one gallblader perforation. At a median time of 40 months of follow-up (range 4-89 months), one hernia recurrence was found (3.7%), there were no reoperations at the time of the interview and there were no cases of mesh infection. Complications of surgery includes one ipsilateral testicular atrophy 4.8% and 1 ipsilateral inguinal seroma 4.8%. CONCLUSIONS: In this series of cases, adding clean contaminated surgery to the inguinal TAPP hernioplasty was not associated with an increase in the infection of the mesh.

Different radiation dose rate as radioprotection and the cross effect with chromium using in vivo somatic cells of Drosophila.

Ionizing radiation plays a key role in the adaptation of an individual organism to environmental pollution, at the same time, it has biological effects that depend on radiation intensity or dose rate (DR). Although the effect of DR has been studied in vitro, the phenomenon known as the inverse effect of DR, which indicates as it decreases that the induction of damage is greater, has not been widely studied in vivo. The present study is aimed to test 0.5 and 1 Gy in somatic cells of the wing of D. melanogaster, administered at 5.4 or 34.3 Gy/h and from 0.037 to 0.3 mM of CrO3 as conditioning treatment. No changes were found in larva-to-adult viability. A protective as well as a cross effect of pre-exposure to different DR and CrO3 concentrations against genetic damage induced by 20 Gy or 1 mM CrO3 was evident.

¿Cómo afrontar un paciente con dependencia a benzodiacepinas en atención primaria? Estrategias para la deshabituación / How to face a patient with benzodiazepine dependence in primary health care? Strategies for withdrawal

Las benzodiacepinas son fármacos ampliamente utilizados en atención primaria de salud. Su uso prolongado se ha convertido en un problema relevante dadas las consecuencias médicas que ocasionan, especialmente en adultos mayores. Entre otras, estas son: dependencia, deterioro cognitivo y riesgo de caídas. Además, los médicos que trabajan en atención primaria cuentan con pocas herramientas para ayudar al paciente en su deshabituación. Se realizó una búsqueda y revisión de la mejor evidencia disponible sobre estrategias prácticas para el médico no especialista en adicciones, para evitar la dependencia al momento de la prescripción inicial y en el paciente con uso prolongado y probablemente dependiente. Se encontraron 10 revisiones sistemáticas relevantes que mostraron evidencia a favor del uso de estrategias multifacéticas en la prescripción, disminución progresiva, cartas y consejería estandarizadas, farmacoterapia y psicoterapia cognitiva conductual. Una estrategia sencilla, eficaz y duradera para prescribir benzodiacepinas es informar al paciente de la necesidad de reducir su consumo, dándole por escrito la pauta de retirada, señalando sus posibles efectos y su solución. Debido a la evidencia disponible, se propone un modelo integrado y escalonado para el manejo del paciente usuario de benzodiacepinas, desde su prescripción hasta su descontinuación.

Benzodiazepines are widely used in primary health care, and their prolonged use is an important problem given the medical consequences particularly in older adults, such as dependence, cognitive impairment, and risk of falls, among others. Primary care doctors generally have few tools to help with managing withdrawal from benzodiazepines. We conducted a review of the best available evidence on practical strategies to avoid dependence at the time of the initial prescription, and to help the patient with prolonged and probably dependent use. We found ten relevant systematic reviews showing evidence in favor of the use of multifaceted prescription strategies, gradual dose reduction, standardized letters, standardized counseling, pharmacotherapy and cognitive behavioral psychotherapy. For benzodiazepine withdrawal, a simple strategy that can be effective and long-lasting is to inform patients of the need to reduce consumption, giving them in writing the withdrawal guideline, indicating the possible effects of withdrawal and its solution. Given the available evidence, an integrated and step-by-step model is proposed for the management of the benzodiazepine user, from prescription to withdrawal.

¿Es la mitomicina C superior al 5-fluorouracilo como antimetabolito en la trabeculectomía para el glaucoma? / Is mytomicyn better than 5-fluorouracil as antimetabolite in trabeculectomy for glaucoma?

INTRODUCCIÓN: La trabeculectomía es considerada la intervención de elección en pacientes con glaucoma con indicación de manejo quirúrgico. Dentro de los factores asociados al fracaso de este tratamiento se encuentra la cicatrización postoperatoria. Para disminuir este factor se han usado distintos antimetabolitos, en particular el 5-fluorouracilo y la mitomicina C. Si bien ambos se consideran efectivos, no está claro si existen diferencias entre ambos en relación al éxito de la trabeculectomía y los efectos adversos. MÉTODOS: Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, reanalizamos los datos de los estudios primarios, realizamos un metanálisis, preparamos tablas de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Identificamos cuatro revisiones sistemáticas que en conjunto incluyen 17 estudios primarios, de los cuales, 12 corresponden a ensayos aleatorizados. Concluimos que el uso de mitomicina C podría lograr una mayor disminución de la presión intraocular e incrementar la tasa de éxito calificado en comparación con el 5-fluorouracilo. Sin embargo, su uso podría asociarse a una mayor incidencia de complicaciones.

INTRODUCTION: Trabeculectomy is considered the standard for glaucoma surgery. Postoperative scarring is one the factors associated with surgery failure. Different antimetabolites have been used in order to reduce this risk, particularly 5-fluorouracil and mitomycin C. Although both are considered effective, it is not clear if they are different in terms of success of trabeculectomy and adverse effects. METHODS: To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified four systematic reviews including 17 studies overall, of which 12 were randomized trials. We concluded mitomycin C might be more effective in reducing intraocular pressure and increasing qualified success compared to 5-fluorouracil. However, its use might be associated to a higher risk of complications.

¿Es la válvula Ahmed superior al implante Baerveldt como derivación acuosa para el manejo del glaucoma? / Is Ahmed valve superior to Baerveldt implant as an aqueous shunt for the treatment of glaucoma?

Resumen INTRODUCCIÓN: La derivación acuosa ha surgido como una técnica alternativa a la trabeculectomía, considerada la cirugía de elección en pacientes con glaucoma. Actualmente, se considera que la principal indicación de esta técnica es ante el fracaso de la trabeculectomía o en tipos de glaucoma que tienen alto riesgo de fracasar. La válvula Ahmed y el implante Baerveldt son las derivaciones acuosas más utilizadas. Sin embargo, no está claro cuáles son las diferencias entre estas dos alternativas. MÉTODOS: Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud a nivel mundial, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, reanalizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Identificamos cinco revisiones sistemáticas que en conjunto incluyeron 10 estudios primarios, de los cuales dos son ensayos aleatorizados. Concluimos que la válvula Ahmed probablemente logra una menor disminución de la presión intraocular; podría lograr un menor éxito calificado y probablemente necesita más reintervenciones que el implante Baerveldt. Respecto al perfil de seguridad, la válvula Ahmed no se presenta claramente superior ni inferior al implante Baerveldt.

Abstract INTRODUCTION: Aqueous shunt has emerged as an alternative technique to trabeculectomy, considered the standard for glaucoma surgery. Currently, it is mainly indicated after failure of trabeculectomy or in glaucoma with high risk of failure. The Ahmed valve and the Baerveldt implant are the most commonly used aqueous shunts. However, it is not clear whether there are differences between them. METHODS.: o answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified five systematic reviews including 10 studies overall, of which two were randomized trials. We concluded the Ahmed valve probably achieves a lower decrease in intraocular pressure, might lead to less qualified success and probably needs more reinterventions than the Baerveldt implant. Regarding safety profile, the Ahmed valve is not clearly superior or inferior to the Baerveldt implant.

Derivación acuosa versus trabeculectomía para el manejo del glaucoma / Aqueous shunt versus trabeculectomy for treatment of glaucoma

INTRODUCCIÓN: La derivación acuosa ha surgido como una técnica alternativa a la trabeculectomía, la cual se considera el tratamiento estándar para cirugía de glaucoma. Actualmente, su principal indicación es en el glaucoma con trabeculectomía fallida o en algunos tipos de glaucoma con alto riesgo de fracaso. Sin embargo, aún existe controversia con respecto a su efectividad en comparación con la trabeculectomía. MÉTODOS: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Identificamos cinco revisiones sistemáticas que en conjunto incluyeron nueve estudios primarios, de los cuales, cuatro corresponden a ensayos aleatorizados. Concluimos que la derivación acuosa podría aumentar el éxito calificado en comparación con la trabeculectomía, pero que no está claro si tiene algún efecto sobre el resto de los desenlaces críticos para la toma de decisión, porque la certeza de la evidencia es muy baja.

INTRODUCTION: Aqueous shunt has emerged as an alternative technique to trabeculectomy, which is considered the standard treatment for glaucoma surgery. Currently, it is mainly indicated after failure of trabeculectomy or in some types of glaucoma with high risk of failure. However, there is still controversy regarding its effectiveness compared to trabeculectomy. METHODS: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified five systematic reviews including nine studies overall, of which four were randomized trials. We concluded that aqueous shunt might increase the qualified success compared to trabeculectomy, but it is not clear whether it has any effect on the rest of the critical outcomes for decision-making because the certainty of the evidence is very low.

Do different tendons exhibit the same response following chronic exposure to statins?

Over the past few years, a number of cases of tendon injuries associated with statin therapy have been reported. In this study, we assessed whether statins can affect the extracellular matrix (ECM) of the deep digital flexor tendon (DDFT) and patellar tendon (PT). Wistar rats were assigned to groups treated with atorvastatin (A20, A80), treated with simvastatin (S20, S80), and control. Zymography, Western blotting for collagen I, non-collagenous proteins (NCP), glycosaminoglycans (GAGs), and hydroxyproline quantifications were performed. DDFT findings: NCP were increased in A20 and A80; higher concentration of hydroxyproline was found in S80; levels of GAGs was increased in all statin-treated groups; collagen I was increased in S80 and pro-MMP-2 activity was reduced in A80, S20, and S80. PT findings: NCP were reduced in A20, A80, and S80; GAGs was reduced in A80 and S20; collagen I was increased in A20 and pro-MMP-2 activity was reduced in the S20. Both the statins provoked marked changes in both tendons. All these changes may make the tendons more prone to microdamage and ruptures. Therefore, a better understanding of the behavior of the tendon ECM components under statin therapy may provide important insights into the mechanisms behind statin-induced tendon injuries.

Time course of changes in heart rate and blood pressure variability in rats with myocardial infarction.

Our aim was to determine the time course of changes in autonomic balance in the acute (1 and 3 days), sub-acute (7 days) and chronic (28 days) phases of myocardial infarction (MI) in rats. Autonomic balance was assessed by temporal and spectral analyses of blood pressure variability (BPV) and heart rate variability (HRV). Pulsatile blood pressure (BP) recordings (30 min) were obtained in awake and unrestrained male Wistar rats (N = 77; 8-10 weeks old) with MI (coronary ligature) or sham operation (SO). Data are reported as means±SE. The high frequency (HF) component (n.u.) of HRV was significantly lower in MI-1- (P<0.01) and MI-3-day rats (P<0.05) than in their time-control groups (SO-1=68±4 vs MI-1=35.3±4.3; SO-3=71±5.8 vs MI-3=45.2±3.8), without differences thereafter (SO-7=69.2±4.8 vs MI-7=56±5.8; SO-28=73±4 vs MI-28=66±6.6). A sharp reduction (P<0.05) of BPV (mmHg2) was observed in the first week after MI (SO-1=8.55±0.80; SO-3=9.11±1.08; SO-7=7.92±1.10 vs MI-1=5.63±0.73; MI-3=5.93±0.30; MI-7=5.30±0.25). Normal BPV, however, was observed 4 weeks after MI (SO-28=8.60±0.66 vs MI-28=8.43±0.56 mmHg2; P>0.05). This reduction was mainly due to attenuation of the low frequency (LF) band of BPV in absolute and normalized units (SO-1=39.3±7%; SO-3=55±4.5%; SO-7=46.8±4.5%; SO-28=45.7±5%; MI-1=13±3.5%; MI-3=35±4.7%; MI-7=25±2.8%; MI-28=21.4±2.8%). The results suggest that the reduction in HRV was associated with decrease of the HF component of HRV suggesting recovery of the vagal control of heartbeats along the post-infarction healing period. The depression of BPV was more dependent on the attenuation of the LF component, which is linked to the baroreflex modulation of the autonomic balance.

Study on the relationship of genotoxic and oxidative potential of a new mixed chelate copper antitumoral drug, Casiopeina II-gly (Cas II-gly) in Drosophila melanogaster.

The present study evaluates the superoxide dismutase (SOD) and catalase (CAT) activities in a wild strain of Drosophila melanogaster and the genotoxic potential induced by Cas II-gly (a new antineoplastic drug) using the somatic mutation and recombination test. Larvae 48h old were treated with Cas II-gly in a range of 0-1.5mM and aliquot were taken every 24h to have individuals treated for 24, 48, 72h and adulthood as well. A dose-dependent toxicity and a significant increase in SOD and CAT activities were found after a 24 and 48h treatment with 0.5-1.5mM concentrations. The comparison of the effect in enzymes with mutation indicated a positive correlation with increased genetic damage, after 24 and 48h of exposure for all concentrations tested. The addition of the genetic damage induced in each exposure time showed a significant effect, but only the small single spots had a concentration-related increase.

Relationship between salt consumption measured by 24-h urine collection and blood pressure in the adult population of Vitória (Brazil).

High salt intake is related to an increase in blood pressure and development of hypertension. However, currently, there are no national representative data in Brazil using the gold standard method of 24-h urine collection to measure sodium consumption. This study aimed to determine salt intake based on 24-h urine collection in a sample of 272 adults of both genders and to correlate it with blood pressure levels. We used a rigorous protocol to assure an empty bladder prior to initiating urine collection. We excluded subjects with a urine volume <500 mL, collection period outside of an interval of 23-25 h, and subjects with creatinine excretion that was not within the range of 14.4-33.6 mg/kg (men) and 10.8-25.2 mg/kg (women). The mean salt intake was 10.4±4.1 g/day (d), and 94% of the participants (98% of men and 90% of women) ingested more than the recommended level of 5 g/d. We found a positive association between salt and body mass index (BMI) categories, as well as with salt and blood pressure, independent of age and BMI. The difference in systolic blood pressure reached 13 mmHg between subjects consuming less than 6 g/d of salt and those ingesting more than 18 g/d. Subjects with hypertension had a higher estimated salt intake than normotensive subjects (11.4±5.0 vs 9.8±3.6 g/d, P<0.01), regardless of whether they were under treatment. Our data indicate the need for interventions to reduce sodium intake, as well the need for ongoing, appropriate monitoring of salt consumption in the general population.

Effect of Calendula officinalis cream on achilles tendon healing.

In recent years, the scientific community has undertaken research on plant extracts, searching for compounds with pharmacological activities that can be used in diverse fields of medicine. Calendula officinalis L. is known to have antioxidant, anti-inflammatory, antibacterial, and wound healing properties when used to treat skin burns. Therefore, the purpose of this study was to analyze the effects of C. officinalis on the initial phase of Achilles tendon healing. Wistar rats were separated in three groups: Calendula (Cal)-rats with a transected tendon were treated with topical applications of C. officinalis cream and then euthanized 7 days after injury; Control (C)-rats were treated with only vehicle after transection; and Normal (N)-rats without tenotomy. Higher concentrations of hydroxyproline (an indicator of total collagen) and non-collagenous proteins were observed in the Cal group in relation to the C group. Zymography showed no difference in the amount of the isoforms of metalloproteinase-2 and of metalloproteinase-9, between C and Cal groups. Polarization microscopy images analysis showed that the Cal group presented a slightly higher birefringence compared with the C group. In sections of tendons stained with toluidine blue, the transected groups presented higher metachromasy as compared with the N group. Immunocytochemistry analysis for chondroitin-6-sulfate showed no difference between the C and Cal groups. In conclusion, the topical application of C. officinalis after tendon transection increases the concentrations of collagen and non-collagenous proteins, as well as the collagen organization in the initial phase of healing.

Effect of the Arrabidaea chica extract on collagen fiber organization during healing of partially transected tendon.

AIMS: After undergoing lesions, tendons have disorganized collagen fibers compared to undamaged tendons. Arrabidaea chica leaves have the aglycones carajurin and carajurone, components of the antocyanins, with a strong pharmacological potential due to their healing properties. Thus, the aim of this study was to investigate the effect of topical application of A. chica extract during tendon healing. MAIN METHODS: The calcaneal tendon of Wistar rats was partially transected with subsequent treatment with A. chica extract (2.13 g/mL) followed by excision on the 7th, 14th and 21st days. Control rats received only saline treatment. KEY FINDINGS: Transmission electron microscopy analysis showed the presence of a large amount of small segments of collagen fibrils in the transected region of the tendons on the 7th day in both the control and plant-treated groups. Considering the organization of the collagen fibers, higher values of birefringence were observed under polarization microscopy in the tendons of the plant-treated group on the 14th day compared to the control group. A larger quantity of dermatan sulfate was also detected after plant treatment in the same period. However, lesser dermatan and chondroitin sulfate were detected in the plant-treated group than in the control group on the 21st day. No differences were found in the values of birefringence between these groups. Intense metachromasy was observed in both transected groups on the 21st day. SIGNIFICANCE: In conclusion, the use of A. chica extract improves collagen organization and increases the quantity of dermatan sulfate on the 14th day of the tendon healing.

Arrabidaea chica extract improves gait recovery and changes collagen content during healing of the Achilles tendon.

INTRODUCTION: Tendon lesions are still a serious clinical problem. The leaves of the Bignoniaceae Arrabidaea chica (Humb. & Bonpl.) B. Verlot. (syn. Bignonia chica (Bonpl.)) have been used in traditional medicine and described in the literature for its healing properties. However, no study has shown the effects of A. chica during tendon healing. The aim of this study was to investigate the healing properties of the A. chica leaves extract on tendons after partial transection. METHODS: A partial transection in the tension region of the Achilles tendon of rats was performed with subsequent posterior topical application of A. chica extract (2.13g/mL in 0.85% saline solution) at the site of the injury. The animals (n=154) were separated into 7 groups: N - rats with tendons without transection; S7, S14 and S21 - rats with tendons treated with topical applications of saline for 7 days and sacrificed on the 7th, 14th and 21st days after surgery, respectively; A7, A14 and A21 - rats with tendons treated with topical applications of the plant extract. The transected regions of the tendons were analyzed through biochemical, morphological and functional analyses. To evaluate the type and concentration of collagen, Western blotting for collagen types I and III was performed, and the hydroxyproline concentration was determined. The participation of metalloproteinases (MMP)-2 and -9 during tendon remodelling was investigated through zymography. Gait recovery was analyzed using the catwalk system. The organization of the extracellular matrix and morphometry were detected in sections stained with haematoxylin-eosin. RESULTS: The application of A. chica extract in the region of tendon injury led to an increase in the amount of hydroxyproline (mg/g tissue) on the 7th (91.5±18.9) and 21st (95.8±11.9) days after the tendon lesion relative to the control groups treated with saline (S7: 75.2±7.2; and S21: 71.9±7.9). There were decreases in collagen types I and III (as determined by densitometry) in the groups treated with the plant extract 7 days after injury (type I: 103.9±15.9; type III: 206.3±8.1) compared to the saline-treated groups (type I: 165.2±31.1; type III: 338.6±48.8). The plant extract stimulated the synthesis of MMP-2 on the 21st day after the lesion and decreased the amount of latent and active isoforms of MMP-9 on the 14th day. Analysis by the catwalk system (max contact intensity) showed that the A. chica extract improved the gait of rats on the 7th day of the healing process when compared to the saline group. CONCLUSIONS: The use of A. chica extract during the healing process of the tendon leads to an increase in collagen content and improved gait recovery. Further studies will be performed to analyze the effect of this plant extract on the organization of the collagen bundles of tendons after lesions and to study its probable anti-inflammatory effect.

Structural and biochemical alterations during the healing process of tendons treated with Aloe vera.

AIMS: The tendon is composed of highly organized collagen fibers that form a complex supramolecular structure. After lesions, the organization and composition of the tendon are not completely restored. Our purpose was to evaluate if the application of Aloe vera improves tendon healing, considering the effectiveness in the stimulus of collagen synthesis. MAIN METHODS: The calcaneal tendon of male Wistar rats was partially transected with subsequent topical application of A. vera ointment at the injury. The animals were separated into groups with tendons treated with the A. vera extract for 7days and excised on the 7th, 14th and 21st days after surgery; control rats received only ointment base without plant extract. KEY FINDINGS: Morphological analysis using polarization microscopy showed that the entire tendon undergoes a remodeling process, with disorganized collagen fibers by days 7 and 14 in plant-treated and non-treated groups and with a higher birefringence in tendons of the plant-treated group on the 21st day. A higher concentration of hydroxyproline was found in plant-treated tendons on days 7 and 14 compared with their controls. Western blots showed lower amounts of type I collagen in the plant-treated group on day 14 compared with the control. MMP-9 diminished 14days after lesion and the active isoform of MMP-2 increased on day 21 in plant-treated groups. SIGNIFICANCE: The present study indicates a beneficial effect of A. vera in the tissue reorganization in the transected region of the tendon 21days after injury and is supported by an increase of active MMP-2.

A study of the inhibition/promotion effects of sodium-copper chlorophyllin (SCC)-mediated mutagenesis in somatic cells of Drosophila.

Sodium-copper chlorophyllin (SCC), a copper-porphyrin complex, has been shown to act as an inhibitor as well as a promoter of DNA-damage induction by a variety of mutagens in several test systems. In order to investigate the basis of this dual effect, experiments were carried out to compare the influence of pretreatment with intact SCC and that of its constituents, the metal-free protoporphyrin (PP-IX) and copper as CuCl(2). The wing-spot test was employed to monitor mutational events in somatic cells of Drosophila melanogaster. Heterozygous mwh+/+flr(3) larvae were treated for 24h with SCC, PP-IX, CuCl(2) or sucrose. Following this treatment, one group of larvae were immediately allowed to feed on instant medium containing 0.5mM N-nitroso-N-ethylurea (ENU) dissolved in phosphate buffer to reach pH 6. The remaining larvae received treatment with ENU with a delay of 1, 2 or 3days (DTD). Results revealed an (a) overall inhibitory effect for 0-DTD and 1-DTD after pretreatment with SCC, (b) only in 0-DTD after PP-IX, and (c) in all DTDs after treatment with CuCl(2). These results provide evidence that the copper ion plays a central role in the antimutagenic effect of SCC, and for a sustained period of time. Pretreatment with SCC and PP-IX produced a promoter effect at 2-DTD and 3-DTD. The results could be explained as an effect of the accumulation of metal-free porphyrin following the dissociation of the copper-porphyrin complex (SCC), the copper-ion reaching proteins to form complexes and participated in anabolic pathways.

Reproducibility of heart rate variability parameters measured in healthy subjects at rest and after a postural change maneuver.

Heart rate variability (HRV) provides important information about cardiac autonomic modulation. Since it is a noninvasive and inexpensive method, HRV has been used to evaluate several parameters of cardiovascular health. However, the internal reproducibility of this method has been challenged in some studies. Our aim was to determine the intra-individual reproducibility of HRV parameters in short-term recordings obtained in supine and orthostatic positions. Electrocardiographic (ECG) recordings were obtained from 30 healthy subjects (20-49 years, 14 men) using a digital apparatus (sampling ratio = 250 Hz). ECG was recorded for 10 min in the supine position and for 10 min in the orthostatic position. The procedure was repeated 2-3 h later. Time and frequency domain analyses were performed. Frequency domain included low (LF, 0.04-0.15 Hz) and high frequency (HF, 0.15-0.4 Hz) bands. Power spectral analysis was performed by the autoregressive method and model order was set at 16. Intra-subject agreement was assessed by linear regression analysis, test of difference in variances and limits of agreement. Most HRV measures (pNN50, RMSSD, LF, HF, and LF/HF ratio) were reproducible independent of body position. Better correlation indexes (r > 0.6) were obtained in the orthostatic position. Bland-Altman plots revealed that most values were inside the agreement limits, indicating concordance between measures. Only SDNN and NNv in the supine position were not reproducible. Our results showed reproducibility of HRV parameters when recorded in the same individual with a short time between two exams. The increased sympathetic activity occurring in the orthostatic position probably facilitates reproducibility of the HRV indexes.

Reproducibility of heart rate variability parameters measured in healthy subjects at rest and after a postural change maneuver

Heart rate variability (HRV) provides important information about cardiac autonomic modulation. Since it is a noninvasive and inexpensive method, HRV has been used to evaluate several parameters of cardiovascular health. However, the internal reproducibility of this method has been challenged in some studies. Our aim was to determine the intra-individual reproducibility of HRV parameters in short-term recordings obtained in supine and orthostatic positions. Electrocardiographic (ECG) recordings were obtained from 30 healthy subjects (20-49 years, 14 men) using a digital apparatus (sampling ratio = 250 Hz). ECG was recorded for 10 min in the supine position and for 10 min in the orthostatic position. The procedure was repeated 2-3 h later. Time and frequency domain analyses were performed. Frequency domain included low (LF, 0.04-0.15 Hz) and high frequency (HF, 0.15-0.4 Hz) bands. Power spectral analysis was performed by the autoregressive method and model order was set at 16. Intra-subject agreement was assessed by linear regression analysis, test of difference in variances and limits of agreement. Most HRV measures (pNN50, RMSSD, LF, HF, and LF/HF ratio) were reproducible independent of body position. Better correlation indexes (r > 0.6) were obtained in the orthostatic position. Bland-Altman plots revealed that most values were inside the agreement limits, indicating concordance between measures. Only SDNN and NNv in the supine position were not reproducible. Our results showed reproducibility of HRV parameters when recorded in the same individual with a short time between two exams. The increased sympathetic activity occurring in the orthostatic position probably facilitates reproducibility of the HRV indexes.

Effects of chronic treadmill training on body mass gain and visceral fat accumulation in overfed rats.

This study evaluated the effects of chronic treadmill training on body mass gain and visceral fat accumulation in overfed rats. Overfeeding was induced by reducing the litter size to 3 male pups per mother during the suckling period. The litter size of control rats was adjusted to 10 male pups per mother. Seven weeks after birth overfed and normally fed rats were selected and assigned to a sedentary protocol or to a low-intensity treadmill training protocol (60 min, 5 times/week, for 9 weeks). Four groups (overfed sedentary, N = 23; normally fed sedentary, N = 32; overfed exercised, N = 18, and normally fed exercised, N = 18) were evaluated at 18 weeks. Data are reported as means +/- SEM. Initial body weight was similar in control and overfed rats [8.0 +/- 0.2 g (N = 42) vs 8.0 +/- 0.1 g (N = 50); P > 0.05] and body weight gain during the suckling period was higher in the overfed rats (30.6 +/- 0.9 vs 23.1 +/- 0.3 g; P < 0.05). Exercise attenuated the body weight gain of overfed compared to sedentary rats (505 +/- 14 vs 537 +/- 12 g; P < 0.05). The sedentary overfed rats showed higher visceral fat weight compared to normally fed animals (31.22 +/- 2.08 vs 21.94 +/- 1.76 g; P < 0.05). Exercise reduced visceral fat by 36.5% in normally fed rats and by 35.7% in overfed rats. Exercise attenuated obesity in overfed rats and induced an important reduction of visceral fat.