Heat stress has divergent effects on the milk microbiota of Holstein and Brown Swiss cows.

Heat stress (HS) is one of the pivotal causes of economic losses in dairy industries and affects welfare and performance, but its effect on milk microbiota remains elusive. It is also unclear if and how different breeds may cope with HS in sustaining productive performance. The objectives of this study were to compare a) the performance of 2 dairy breeds, namely Holstein and Brown Swiss, subjected to HS and b) the different effects of HS on the milk microbiota of the 2 breeds in thermal comfort conditions and HS. The study was carried out on 36 dairy cows, 18 per breed. The HS was induced by switching off the cooling system during a natural heat wave for 4 d. Besides the Temperature Humidity Index (THI), the animal stress was confirmed by measuring respiratory frequency and rectal temperature twice daily at 4 a.m. and 3 p.m. The HS differently impacted the 2 breeds. Rectal temperatures were higher in Holstein cows, while no changes in rectal temperature were found in Brown Swiss. Milk yield recording and sampling were performed during the morning milking of d 1 (at 4.00 a.m.) and afternoon milking of d 4 (at 5.00 p.m.). Productive parameters were also different: milk yield, fat-corrected milk, energy-corrected milk, protein and casein content, and renneting parameters were decreased in Holstein but remained unaffected in Brown Swiss. The HS also modified the milk microbiota of the 2 breeds differently. During HS, the Brown Swiss milk microbiota was richer (α diversity) than the Holstein one. Comparing the time points before and during HS within breeds showed that Brown Swiss milk microbiota was less affected by HS than Holstein's. Under the same thermal comfort condition, milk microbiota did not discriminate between Brown Swiss and Holstein. Consistently with α and ß diversity, the number of operational taxonomic units (OTUs) at the genus level that changed their abundance during HS was higher in Holstein (74 OTUs) than in Brown Swiss (only 20 OTUs). The most significant changes in abundance affected Acinetobacter, Chryseobacterium, Cutibacterium, Enterococcus, Lactococcus, Prevotella-9, Serratia, and Streptococcus. In conclusion, the present report confirms and extends previous studies by demonstrating that Brown Swiss cows regulate their body temperature better than the Holstein breed. The relative thermal tolerance to HS compared with Holstein is also confirmed by changes in milk uncultured microbiota, which were more evident in Holstein than in Brown Swiss.

Acute toxicity of essential oils of Aloysia triphylla (L'Hér.) Britton, Lippia gracilis Schauer, and Piper aduncum L. in Colossoma macropomum (Cuvier, 1818).

The aim of this study was to determine the acute toxicity of the essential oils (EOs) of Aloysia triphylla, Lippia gracilis and Piper aduncum in juvenile tambaqui (Colossoma macropomum), and evaluate the possible histopathological alterations in their gills. For the acute toxicity tests, juvenile tambaqui (n=24/treatment) were distributed in six treatments with three replicates, which comprised the control and five EO concentrations of A. triphylla (60, 80, 100, 120 and 140 mg L-1), L. gracilis (35, 40, 45, 50 and 55 mg L-1) and P. aduncum (42.5, 45, 47.5, 50 and 52.5 mg L-1), with an exposure period of 4 h. The mortality rate and severity of damage to the tambaqui gills were proportional to the increase in the concentration of the EO, with LC50-4 h values estimated at 109.57 mg L -1 for A. triphylla, 41.63 mg L -1 for L. gracilis and 48.17 mg L -1 for P. aduncum. The main morphological damages observed in the gills of the tambaqui exposed to the three EOs, were Grade I: hypertrophy and hyperplasia of lamellar epithelial cells, lamellar fusion, epithelial detachment, capillary dilation and constriction, proliferation of chloride cells and mucosal cells and edema; in low frequency Grade II damage as epithelial rupture and lamellar aneurysm. Necrosis (Grade III damage) was observed only in gill lamellae exposed to P. aduncum EO (47.5, 50.0 and 52.5 mg L-1). Concentrations of EOs below LC50-4 h can be used sparingly, for short periods of exposure for the treatment of diseases in tambaqui breeding.

Redox imbalance in age-related ovarian dysfunction and perspectives for its prevention.

The age at which women have their first child is increasing. This change represents a major health problem to society because advanced maternal age is related with a decay in fertility and an increase in the incidence of a variety of pregnancy complications and offspring health issues. The ovary stands as the main contributor for female reproductive ageing because of the progressive age-related decrease in follicle number and oocyte quality. Loss of redox homeostasis and establishment of an ovarian oxidative microenvironment are seen as major underlying causes for such downfall and impairment of ovarian function. Thus, the use of antioxidants to preserve fertility became an important field of research. In this review, new insights on mechanisms underlying the establishment of oxidative stress and its repercussions on ovarian ageing are addressed, along with the current state of knowledge on antioxidant supplementation and its contribution for healthy ageing and extension of ovarian lifespan.

Age-related oxidative modifications to uterine albumin impair extravillous trophoblast cells function.

Advanced maternal age is associated not only with a significant reduction in fertility but also with an additional risk of developing pregnancy-related disorders. Most of these disorders are now believed to be the clinical manifestation of an incorrect placentation, namely deficient transformation of maternal spiral arteries and ineffective trophoblast invasion through uterine stroma. In the present study it was hypothesized that an age-related loss in uterine redox homeostasis interferes with the function of extravillous trophoblasts (EVTs) and placentation. To test this hypothesis, relative levels of oxidatively modified proteins were evaluated in human samples from placenta and placental bed, and the role of specific oxidative modifications to proteins in placentation was studied using a cell culture model of EVTs. In the placental bed, the carbonylation level of a 66 kDa protein (identified as albumin) presented a strong, positive and significant correlation with maternal age. Albumin was immunodetected preferentially in endothelial cells and connective tissue between muscle fascicles. In vitro results showed that carbonylated albumin overload did not alter cell viability, but reduced EVTs motility and triggered cell stress response pathways. Moreover, EVTs presented decreased ability to adhere to and invade a collagen extracellular matrix pre-treated with carbonylated albumin. In conclusion, reproductive ageing is accompanied by an increase in maternal uterine carbonylated albumin, that may have a deleterious role in the modulation of EVTs function.

Involvement of glutathione metabolism in Eichhornia crassipes tolerance to arsenic.

Aquatic macrophytes are potentially useful for phytoremediation programmes in environments contaminated by arsenic (As). Biochemical and physiological modification analyses in different plant parts are important to understand As tolerance mechanisms. The objective was to evaluate glutathione metabolism in leaves and roots of Eichhornia crassipes (Mart.) Solms treated to As. Specimens of E. crassipes were cultured for 3 days in Clark's nutrient solution containing 7 µm As. The enzymes ATP sulphurylase (ATPS), glutathione reductase (GR), glutathione peroxidase (GSH-Px), glutathione sulphotransferase (GST) and γ-glutamylcysteine synthetase (γ-ECS) activity, glutathione content, total protein and non-protein thiols were evaluated. The ATPS activity increased in roots. GR activity in leaves and GSH-Px in roots were lower. GST activity was higher in roots and lower in leaves, and γ-ECS activity was higher in leaves. Glutathione levels were lower, total thiol levels were higher and non-protein levels did not change in E. crassipes leaves and roots. Exposure to As increased enzyme activity involved with sulphur metabolism, such as ATPS. Higher GR activity and lower GSH-Px indicate increased glutathione conjugation to As due to increased GSH availability. The higher GST activity indicates its participation in As detoxification and accumulation through As GSH conjugation. Changes in glutathione and thiol levels suggest high phytochelatin synthesis. In conclusion, the increments in ATPS, GR, GST and γ-ECS activity indicate that these enzymes are involved in GSH metabolism and are part of the E. crassipes As detoxification mechanism.

Apocynin Dietary Supplementation Delays Mouse Ovarian Ageing.

Advanced maternal age is associated with higher infertility rates, pregnancy-associated complications, and progeny health issues. The ovary is considered the main responsible for these consequences due to a continuous decay in follicle number and oocyte quality. Intracellular imbalance between oxidant molecules and antioxidant mechanisms, in favour of the former, results in oxidative stress (OS) that is believed to contribute to ovarian ageing. This work is aimed at evaluating whether an age-related increase in ovarian OS, inflammation, and fibrosis may contribute to tissue dysfunction and whether specific antioxidant supplementation with a NADPH oxidase inhibitor (apocynin) could ameliorate them. Mice aged 8-12 weeks (reproductively young) or 38-42 weeks (reproductively aged) were employed. Aged mice were divided into two groups, with one receiving apocynin (5 mM) in the drinking water, for 7 weeks, upon which animals were sacrificed and their ovaries collected. Ovarian structure was similar at both ages, but the ovaries from reproductively aged mice exhibited lipofuscin deposition, enhanced fibrosis, and a significant age-related reduction in primordial and primary follicle number when compared to younger animals. Protein carbonylation and nitration, and markers of OS were significantly increased with age. Moreover, mRNA levels of inflammation markers, collagens, metalloproteinases (MMPs), and tissue inhibitor MMPs (TIMPs) were upregulated. Expression of the antifibrotic miRNA29c-3p was significantly reduced. Apocynin supplementation ameliorated most of the age-related observed changes, sometimes to values similar to those observed in young females. These findings indicate that there is an age-related increase in OS that plays an important role in enhancing inflammation and collagen deposition, contributing to a decline in female fertility. Apocynin supplementation suggests that the imbalance can be ameliorated and thus delay ovarian ageing harmful effects.

Nutritional Risk by Mini Nutritional Assessment (MNA), but Not Anthropometric Measurements, Has a Good Discriminatory Power for Identifying Frailty in Elderly People: Data from Brazilian Secondary Care Clinic.

OBJECTIVES: To investigate, in elderly individuals registered at a secondary outpatient clinic, the prevalence of frailty and pre-frailty and to identify the discriminatory power of anthropometric measurements and nutritional risk in identifying these conditions. DESIGN: Cross-sectional study with data extracted from medical records. SETTING AND PARTICIPANTS: Elderly patients (60+ years) from a geriatric outpatient clinic, located in the southeast area of São Paulo, Brazil. MEASUREMENTS: Frailty was assessed using five criteria proposed by Fried et al (2001), with some modifications. Nutritional risk was identified using Mini Nutritional Assessment (MNA). Body weight and body height were measured and used to calculate the body mass index (BMI). The discriminatory power of these parameters for the identification of frailty was determined by Receiver Operating Characteristics (ROC) curves. RESULTS: The final sample was composed of 254 patients, from which 31.1% were identified as frail and 53.5% as prefrail. The MNA indicated that 3.1% were malnourished and 35.4% were at risk of malnutrition. The BMI values 39.4% as overweight/obese and 19.9% as undernourished. As just the MNA revealed differences for frailty classification, only this parameter was investigated by ROC curve. The discriminatory power of the MNA for frailty presented a best cut-off point of ≤23.0 and the AUC was 0.812 (sensitivity=55.7; specificity=94.9), with a youden index of 0.5057 (95%CI= 0.3146-0.5946). MNA did not present sufficient discriminatory power to detect pre-frailty. CONCLUSION: The MNA was capable of indicating frailty, but not pre-frailty in this sample. BMI did not display significant predictive power for frailty or pre-frailty.

Age-related immune response to experimental infection with Eimeria ninakohlyakimovae in goat kids.

Both the immune response developed in ruminants against Eimeria spp. and the ability to bear patent infections seems to be dependent on the age of the host. In the present study we have evaluated the influence of the age in the development of protective immune responses against Eimeria ninakohlyakimovae. For this purpose, 3, 4 and 5-week-old goat kids were infected with sporulated oocysts and subjected to a homologous challenge 3 weeks later. Goat kids primary infected at 6, 7 and 8 weeks of age served as challenge controls, and uninfected animals were used as negative controls. The protective immunity was assessed by clinical, haematological, parasitological, immunological and pathological parameters. Altogether, the results demonstrate that goat kids of either 3, 4 or 5 weeks of age are able to develop patent infections and immunoprotective responses against E. ninakohlyakimovae, as all age groups: (i) released significantly less oocysts after challenge, which was associated to milder clinical signs; (ii) displayed a local immune response, with significant increase of numerous cellular populations; and (iii) had increased levels of IgG and IgM, and mainly of local IgA. Nevertheless, detailed analysis of the data showed some differences between the three age groups, related both to the Eimeria infection outcome and the resulting immune response, suggesting that youngest goat kids are not fully immunocompetent. This finding may be of interest for the design of immunoprophylactic approaches and/or prophylactic/methaphylactic treatments against goat coccidiosis.

Protective immune responses during prepatency in goat kids experimentally infected with Eimeria ninakohlyakimovae.

During the first schizogony, the goat coccidia Eimeria ninakohlyakimovae develops macroschizonts in lacteal duct endothelial cells, whose rupture leads to severe ileal damage and clinical signs during the prepatent period. The immune response elicited against early stages of the parasite development still requires to be investigated. In the present study we have evaluated immune reactions in goat kids primary- and challenged-infected with Eimeria ninakohlyakimovae, and sacrificed during prepatency (7days after challenge). The oocyst output during the primary infection, body weight and clinical condition of all the animals were examined and, at the end of the experiment, all the goat kids were euthanized and subjected to necropsy. Samples were taken from different sections of the ileum, colon and mesenteric lymph nodes (MLN) of primary- and challenged E. ninakohlyakimovae-infected animals. Intestinal leukocyte subpopulations were characterized in E. ninakohlyakimovae-infected mucosa and counts of lymphocytes, eosinophils, polymorphonuclear neutrophils (PMN), globular leukocytes and mast cells were recorded. Additionally, gene expression of caprine IL-2, IL-4, IL-10 and INFγ of ileal, colonic and MLN tissues were performed, as well as the immunohistochemical characterization of immune cells. The E. ninakohlyakimovae primary infection resulted in moderate to severe enteritis with different degrees of diarrhoea and was accompanied by high OPG counts and an increase of most immune cells analyzed when compared to uninfected control animals. Furthermore, eosinophil-, lymphocyte-, globular leukocyte- and mast cell-counts were significantly higher in the challenge group compared to the primary infected animals, whilst the opposite was true for PMN counts. The challenge infection was also associated with moderate increased levels of local mucosal IgA. Interestingly, the number of immature schizonts found at the ileal mucosa was statistically higher in the challenge infected group compared to the challenged control animals. Furthermore, in the challenged E. ninakohlyakimovae-infected animals a significantly higher number of mucosal CD4+ and CD8+ lymphocytes were observed, indicating that these T cell subpopulations might be involved in protective host immune response elicited against early stages of parasite development. The immune response was however very complex, as antigen presenting cells and other effector cell populations of the innate immune system, as well as certain cytokines, were involved. In summary, the results of this study contribute to the better understanding of local cellular and humoral immune responses against caprine E. ninakohlyakimovae, particularly during the prepatency.

Age-related expression of TGF beta family receptors in human cumulus oophorus cells.

PURPOSE: During ovarian follicle growth, local cellular interactions are essential for oocyte quality acquisition and successful fertilization. While cumulus cells (CCs) nurture oocytes, they also deliver oocyte-secreted factors (OSFs) that activate receptors on CCs. We hypothesized that disturbance of those interactions contributes to age-related lower reproductive success in women submitted to assisted reproductive technology treatments. METHODS: Women aged 27-48, without recognized personal reproductive disorder, were enrolled in the study and divided in <35- and ≥35-year-old groups. CCs collected upon follicle aspiration were processed for immunocytochemistry and RNA extraction. The expression patterns of OSF receptors BMPR2, ALK 4, ALK5, and activin receptor-like kinase (ALK6) were studied. RESULTS: Independently of age, receptors were found mostly in the cell periphery. The quantitative assay revealed that in older women, BMPR2, ALK 4, and ALK6 were all significantly decreased, whereas ALK5 was slightly increased. CONCLUSIONS: Female age imparts an effect on the expression of OSF receptors in CCs. The findings indicate that reproductive aging affects the local regulation of signaling pathways mediated by BMPR2, ALK6, and ALK4 receptor activation, suggesting their joint involvement.

A Single Bout of Arm-crank Exercise Promotes Positive Emotions and Post-Exercise Hypotension in Patients with Symptomatic Peripheral Artery Disease.

OBJECTIVE/BACKGROUND: The objective was to analyze the acute effects of a single bout of arm cranking exercise on affective and cardiovascular parameters in patients with symptomatic peripheral artery disease (PAD). METHODS: This was a prospective, controlled, crossover study. Eleven men with symptomatic PAD underwent two experimental sessions in a random order: control or arm crank exercise (15 × 2 minutes bouts of arm crank exercise interrupted by 2 minutes rest intervals). During exercise, ratings of perceived exertion (Borg scale) and affective responses (pleasure/displeasure) were obtained at the first, fifth, tenth, and fifteenth bouts. Before and after the experimental sessions, cardiovascular parameters (blood pressure and heart rate) were obtained. Data were analysed by a two-way repeated measure analysis of variance with significance achieved at p < .05. RESULTS: During the arm crank exercise, patients reported positive feelings of pleasure. During exercise, heart rate (HR) remained within 80-90% of peak HR. Additionally, patients performed arm crank exercise with moderate levels of perceived exertion (Borg rating of 11-13) and with pleasant affective scores (Feeling Scale of +1 to +5). Blood pressure (systolic, diastolic, and mean) increase was lower after arm crank exercise than for control (greatest net effect: -15 ± 11 mmHg [p < .001]; -9 ± 5 mmHg [p < .001]; -9 ± 6 mmHg [p < .001], respectively), while HR increased (greatest net effect: +9 ± 6 beats per minute; p < .001). CONCLUSION: A single bout of arm crank exercise promotes pleasurable feelings while reducing blood pressure in patients with symptomatic PAD.

Effect of 3-nitrooxypropanol on methane and hydrogen emissions, methane isotopic signature, and ruminal fermentation in dairy cows.

The objective of this crossover experiment was to investigate the effect of a methane inhibitor, 3-nitrooxypropanol (3NOP), on enteric methane emission, methane isotopic composition, and rumen fermentation and microbial profile in lactating dairy cows. The experiment involved 6 ruminally cannulated late-lactation Holstein cows assigned to 2 treatments: control and 3NOP (60 mg/kg of feed dry matter). Compared with the control, 3NOP decreased methane emission by 31% and increased hydrogen emission from undetectable to 1.33 g/d. Methane emissions per kilogram of dry matter intake and milk yield were also decreased 34% by 3NOP. Milk production and composition were not affected by 3NOP, except milk fat concentration was increased compared with the control. Concentrations of total VFA and propionate in ruminal fluid were not affected by treatment, but acetate concentration tended to be lower and acetate-to-propionate ratio was lower for 3NOP compared with the control. The 3NOP decreased the molar proportion of acetate and increase those of propionate, butyrate, valerate, and isovalerate. Deuterium-to-hydrogen ratios of methane and the abundance of (13)CH3D were similar between treatments. Compared with the control, minor (4‰) depletion in the (13)C/(12)C ratio was observed for 3NOP. Genus composition of methanogenic archaea (Methanobrevibacter, Methanosphaera, and Methanomicrobium) was not affected by 3NOP, but the proportion of methanogens in the total cell counts tended to be decreased by 3NOP. Prevotella spp., the predominant bacterial genus in ruminal contents in this experiment, was also not affected by 3NOP. Compared with the control, Ruminococcus and Clostridium spp. were decreased and Butyrivibrio spp. was increased by 3NOP. This experiment demonstrated that a substantial inhibition of enteric methane emission by 3NOP in dairy cows was accompanied with increased hydrogen emission and decreased acetate-to-propionate ratio; however, neither an effect on rumen archaeal community composition nor a significant change in the isotope composition of methane was observed.

Immunohistochemical expression of heparanase isoforms and syndecan-1 proteins in colorectal adenomas.

The proteoglycan syndecan-1 and the endoglucuronidases heparanase-1 and heparanase-2 are involved in molecular pathways that deregulate cell adhesion during carcinogenesis. Few studies have examined the expression of syndecan-1, heparanase-1 and mainly heparanase-2 proteins in non-neoplastic and neoplastic human colorectal adenoma tissues. The aim of this study was to analyze the correlation among the heparanase isoforms and the syndecan-1 proteins through immunohistochemical expression in the tissue of colorectal adenomas. Primary anti-human polyclonal anti-HPSE and anti-HPSE2 antibodies and primary anti-human monoclonal anti-SDC1 antibody were used in the immunohistochemical study. The expressions of heparanase-1 and heparanase-2 proteins were determined in tissue samples from 65 colorectal adenomas; the expression of syndecan-1 protein was obtained from 39 (60%) patients. The histological type of adenoma was tubular in 44 (67.7%) patients and tubular-villous in 21 (32.3%); there were no villous adenomas. The polyps were <1.0 cm in size in 54 (83.1%) patients and ≥1.0 cm in 11 (16.9%). The images were quantified by digital counter with a computer program for this purpose. The expression index represented the relationship between the intensity expression and the percentage of positively stained cells. The results showed that the average of heparanase-1, heparanase-2 and syndecan-1 expression index was 73.29 o.u./µm², 93.34 o.u./µm², and 55.29 o.u./µm², respectively. The correlation between the heparanase-1 and syndecan-1 expression index was positive (R=0.034) and significant (P=0.035). There was a negative (R= -0.384) and significant (P=0.016) correlation between the expression index of heparanase-1 and heparanase-2. A negative (R= -0.421) and significant (P=0.008) correlation between the expression index of heparanase-2 and syndecan-1 was found. We concluded that in colorectal adenomas, the heparanase-1 does not participate in syndecan-1 degradation; the heparanase-2 does not stimulate syndecan-1 degradation by the action of heparanase-1, and the heparanase-2 may be involved in the modulation of the heparanase-1 activity.

Modulation of the pro-inflammatory molecules E-selectin and TNF-α gene transcription in Eimeria ninakohlyakimovae-infected primary caprine host endothelial cells.

Eimeria ninakohlyakimovae is an important coccidian parasite of goats which causes severe hemorrhagic typhlocolitis in young animals, thereby leading to high economic losses in goat industry worldwide. The first merogony of E. ninakohlyakimovae occurs within host endothelial cells (ECs) of the lacteal capillaries of the villi of the distal ileum resulting in the formation of macromeronts (up to 170 µm) within 10-12 days post-infection (p.i.) and releasing >120,000 merozoites I. The E. ninakohlyakimovae-macromeront formation within highly immunoreactive host endothelial cells (ECs) should rely on several regulatory processes to fulfill this massive replication. Here host EC-parasite interactions were investigated to determine the extent of modulation carried out by E. ninakohlyakimovae in primary caprine umbilical vein endothelial cells (CUVEC) during the first merogony. Gene transcription of the adhesion molecule E-selectin and the cytokine TNF-α were significantly enhanced in the first hours and days p.i. in E. ninakohlyakimovae-infected CUVEC. The activation of CUVEC was also demonstrated by enhanced chemokine CCL2 and cytokine GM-CSF gene transcription, whereas no differences of the eNOS gene transcription were observed in E. ninakohlyakimovae-infected CUVEC when compared to un-infected controls. The data presented here suggest that infection of caprine host ECs by E. ninakohlyakimovae results in EC activation associated with enhanced gene transcription encoding for pro-inflammatory as well as immunomodulatory molecules, which might be important for the defense against this intracellular parasite.

Effect of platelet-rich plasma therapy associated with exercise training in musculoskeletal healing in rats.

BACKGROUND: Muscle healing is a time-dependent process associated with an increase in the total amount of local collagen fibers. Platelet-rich plasma therapy (PRPT) associated with exercise may improve this healing process. The aim of this study was to demonstrate the regenerative effect of PRPT in association with exercise training on musculoskeletal healing. METHODS: Male Wistar rats were submitted to an injury in the vastus lateralis muscle and randomly divided into 4 groups (n = 5/group): sedentary sham-operated (SSO); sedentary group submitted to PRPT (SPR); swim-trained (SWT); and swim-trained group submitted to PRPT (SWP). Serum lactate level was used to confirm the training protocol effectiveness to increase aerobic fitness. The collagen fiber concentration was measured by the polarization colors in picrosirius red-stained tissue sections. RESULTS: Lactate levels decreased in both training groups (SWT and SWP; P < .05) after training (SWT: from 6.2 ± 0.44 to 4.7 ± 0.22 mmol/L; SWP: from 5.5 ± 0.99 to 4.0 ± 0.78 mmol/L). There were less type 1 collagen fibers in SWP group compared with other groups (SSO = 31.8 ± 10.3, SSP = 32.3 ± 13.5, SWT = 14.6 ± 13.4, SWP = 5.7 ± 4.7, P < .05), while there were more type 3 collagen fibers on SWP (SSO = 68.7 ± 9.8, SSP = 71.2 ± 12.2, SWT = 85.4 ± 13.4, SWP = 94.4 ± 4.6, P < .05) in the injured region. CONCLUSION: Exercise in association with PRPT enhances the skeletal muscle-healing process.

Sport modality affects bradycardia level and its mechanisms of control in professional athletes.

We investigated the influence of sport modalities in resting bradycardia and its mechanisms of control in highly trained athletes. In addition, the relationships between bradycardia mechanisms and cardiac structural adaptations were tested. Professional male athletes (13 runners, 11 cyclists) were evaluated. Heart rate (HR) was recorded at rest on beat-to-beat basis (ECG). Selective pharmacological blockade was performed with atropine and esmolol. Vagal effect, intrinsic heart rate (IHR), parasympathetic (n) and sympathetic (m) modulations, autonomic influence (AI) and autonomic balance (Abal) were calculated. Plasmatic norepinephrine (high-pressure liquid chromatography) and cardiac structural adaptations (echocardiography) were evaluated. Runners presented lower resting HR, higher vagal effect, parasympathetic modulation (n), AI and IHR than cyclists (P<0.05). Abal, sympathetic modulation (m) and norepinephrine level were similar within athletes regardless of modality. The cardiac chambers were also similar between runners and cyclists (P=0.30). However, cyclists displayed higher septum and posterior wall thickness than runners (P=0.04). Further analysis showed a trend towards inverse correlation between IHR with septum wall thickness and posterior wall thickness (P=0.056). Type of sport influences the resting bradycardia level and its mechanisms of control in professional athletes. Resting bradycardia in runners is mainly dependent on an autonomic mechanism. In contrast, a cyclist's resting bradycardia relies on a non-autonomic mechanism probably associated with combined eccentric and concentric hypertrophy.

Pectoralis major myocutaneous flap for head and neck reconstruction: risk factors for fistula formation.

The pectoralis major myocutaneous flap (PMMF) is a safe and versatile flap used widely for head and neck cancer reconstructions, but one of the major and most feared complications is oro- or pharyngocutaneous fistula. Herein, we attempt to establish risk factors for fistula formation in reconstructions of mucosal defects in the head and neck using PMMF through retrospective analysis of PMMF performed during 3 years at a single institution, with a total of 84 procedures. There were 69 men and 15 women, with a mean age of 59.5 years. There were 15 cases of partial flap loss, two total flap losses and 31 fistulas. The independent risk factors for fistula formation were preoperative serum hemoglobin < 13 g/dl, preoperative serum albumin < 3.4 g/dl and hypopharynx reconstruction. The PMMF is still a very useful flap and this is the first multivariate analysis analysing risk factors for fistula formation. These findings are helpful in selecting patients with elevated risk of fistula formation, and therefore preventive measures can be undertaken to avoid potentially serious complications.

Estudo farmacognóstico de folhas e raízes da Spiranthera odoratissima A. St. -Hil. (Rutaceae) / Pharmacognostic study of the leaves and roots of Spiranthera odoratissima A. St. -Hil. (Rutaceae)

A Spiranthera odoratissima A. St.-Hil. (manacá) é um arbusto cujas raízes são utilizadas popularmente contra dores musculares, de estômago e de cabeça, disfunções hepáticas, reumatismo, e como estimulante do apetite. As folhas são empregadas como depurativo do sangue, nas afecções renais e hepáticas. O objetivo deste trabalho foi realizar o estudo morfo-anatômico de S. odoratissima, bem como a triagem fitoquímica, a determinação dos teores de água, cinzas totais e insolúveis em ácido. O material vegetal foi coletado em Leopoldo de Bulhões/ Goiás e os estudos morfo-anatômicos e a triagem fitoquímica foram realizados utilizando as técnicas convencionais. Verificou-se que a folha é hipoestomática, com estômatos anomocíticos e a epiderme apresenta papilas na face abaxial. O mesofilo é dorsiventral e a nervura principal possui drusas de oxalato de cálcio e cavidades secretoras. O pecíolo apresenta sistema vascular em forma circular. Na raiz, em crescimento primário, observou-se cilindro vascular com organização diarca. Na prospecção fitoquímica detectaram-se fenóis, taninos, cumarinas, flavonoides, triterpernos/esteróis, antraquinonas e antocianinas nas folhas e alcaloides, cumarinas, amido e saponinas nas raízes. Esses resultados são parâmetros importantes para o controle de qualidade dessa matéria-prima vegetal.

Spiranthera odoratissima A. St.-Hil. (manacá) is a shrub whose roots are popularly used against stomach pains, headache, muscle pain, liver disorders, rheumatism and as an appetite stimulant. The leaves are used as a blood depurative and for liver and kidney disease. The purpose of this work was to perform the morphological and anatomical study, the phytochemical screening and determine the water content and the levels of total and acid of S. odoratissima. The plant material was collected in Leopoldo de Bulhões/ Goiás and the morpho-anatomical studies and the phytochemical screening were performed using conventional techniques. It was verified that the leaf is hypostomatic, with anomocytic stomata and the epidermis has papillae on the abaxial surface. The mesophyll is dorsiventral and the midrib presents druses of calcium oxalate and secretory cavities. The petiole has a circular vascular system. The root in primary growth presents vascular cylinder with diarchic organization. Phenols, tannins, coumarins, flavonoids, triterpenes/sterols, anthraquinones and anthocyanins were detected in the phytochemical screening of the leaves, and alkaloids, coumarins, saponins and starch were detected in the roots. These results are important parameters for the quality control of the vegetal raw material.