Characterisation of an area of coexistent visceral and cutaneous leishmaniasis transmission in the State of Piauí, Brazil.

BACKGROUND: In Brazil, transmission of visceral and cutaneous leishmaniasis has expanded geographically over the last decades, with both clinical forms occurring simultaneously in the same area. OBJECTIVES: This study characterised the clinical, spatial, and temporal distribution, and performed entomological surveillance and natural infection analysis of a leishmaniasis-endemic area. METHODS: In order to characterise the risk of leishmaniasis transmission in Altos, Piauí, we described the clinical and socio-demographic variables and the spatial and temporal distribution of cases of American visceral leishmaniasis (AVL) and American cutaneous leishmaniasis (ACL) cases and identified potential phlebotomine vectors. FINDINGS: The urban area concentrated almost 54% of ACL and 86.8% of AVL cases. The temporal and spatial distribution of AVL and ACL cases in Altos show a reduction in the number of risk areas, but the presence of permanent disease transmission foci is observed especially in the urban area. 3,808 phlebotomine specimens were captured, with Lutzomyia longipalpis as the most frequent species (98.45%). Of the 35 females assessed for natural infection, one specimen of Lu. longipalpis tested positive for the presence of Leishmania infantum and Leishmania braziliensis DNA. MAIN CONCLUSION: Our results indicate the presence of risk areas for ACL and AVL in the municipality of Altos and highlight the importance of entomological surveillance to further understand a possible role of Lu. longipalpis in ACL transmission.

Characterisation of an area of coexistent visceral and cutaneous leishmaniasis transmission in the State of Piauí, Brazil

BACKGROUND In Brazil, transmission of visceral and cutaneous leishmaniasis has expanded geographically over the last decades, with both clinical forms occurring simultaneously in the same area. OBJECTIVES This study characterised the clinical, spatial, and temporal distribution, and performed entomological surveillance and natural infection analysis of a leishmaniasis-endemic area. METHODS In order to characterise the risk of leishmaniasis transmission in Altos, Piauí, we described the clinical and socio-demographic variables and the spatial and temporal distribution of cases of American visceral leishmaniasis (AVL) and American cutaneous leishmaniasis (ACL) cases and identified potential phlebotomine vectors. FINDINGS The urban area concentrated almost 54% of ACL and 86.8% of AVL cases. The temporal and spatial distribution of AVL and ACL cases in Altos show a reduction in the number of risk areas, but the presence of permanent disease transmission foci is observed especially in the urban area. 3,808 phlebotomine specimens were captured, with Lutzomyia longipalpis as the most frequent species (98.45%). Of the 35 females assessed for natural infection, one specimen of Lu. longipalpis tested positive for the presence of Leishmania infantum and Leishmania braziliensis DNA. MAIN CONCLUSION Our results indicate the presence of risk areas for ACL and AVL in the municipality of Altos and highlight the importance of entomological surveillance to further understand a possible role of Lu. longipalpis in ACL transmission.

LOCUS (LOng Covid-Understanding Symptoms, events and use of services in Portugal): A three-component study protocol.

Approximately 10% of patients experience symptoms of Post COVID-19 Condition (PCC) after a SARS-CoV-2 infection. Akin acute COVID-19, PCC may impact a multitude of organs and systems, such as the cardiovascular, respiratory, musculoskeletal, and neurological systems. The frequency and associated risk factors of PCC are still unclear among both community and hospital settings in individuals with a history of COVID-19. The LOCUS study was designed to clarify the PCC's burden and associated risk factors. LOCUS is a multi-component study that encompasses three complementary building blocks. The "Cardiovascular and respiratory events following COVID-19" component is set to estimate the incidence of cardiovascular and respiratory events after COVID-19 in eight Portuguese hospitals via electronic health records consultation. The "Physical and mental symptoms following COVID-19" component aims to address the community prevalence of self-reported PCC symptoms through a questionnaire-based approach. Finally, the "Treating and living with Post COVID-19 Condition" component will employ semi-structured interviews and focus groups to characterise reported experiences of using or working in healthcare and community services for the treatment of PCC symptoms. This multi-component study represents an innovative approach to exploring the health consequences of PCC. Its results are expected to provide a key contribution to the optimisation of healthcare services design.

Functional exercise capacity in maximal and submaximal activities of individuals with polio sequelae.

PURPOSE: Poliomyelitis is an infectious disease that can cause total paralysis. Furthermore, poliomyelitis survivors may develop new signs and symptoms, including muscular weakness and fatigue, years after the acute phase of the disease, i.e., post-polio syndrome (PPS). Thus, the objective was to compare the functional exercise capacity during maximal and submaximal exercises among individuals with polio sequelae (without PPS diagnosis), PPS, and a control group. METHODS: Thirty individuals participated in three groups: a control group (CG, n = 10); a group of individuals with polio sequelae but without PPS diagnosis (PG, n = 10); and a PPS group (PPSG, n = 10). All participants underwent (i) a cardiopulmonary exercise test to determine their maximal oxygen uptake ([Formula: see text]) and (ii) a series of functional field tests (i.e., walking test, sit-to-stand test, and stair climbing test). RESULTS: [Formula: see text]O2max was 30% lower in PPSG than in CG and PG. Regarding functional field tests, walking and stair climbing test performances were significantly different among all groups. The PPSG sit-to-stand performance was lower than CG. CONCLUSION: The sequelae of paralytic poliomyelitis impair functional exercise capacity obtained from maximal and submaximal tests, especially in patients with PPS. Furthermore, submaximal variables appear to be more negatively impacted than maximal variables.

Risk Burden of Coronary Perforation in Chronic Total Occlusion Recanalization: Latin American CTO Registry Analysis.

Background Coronary perforation is a life-threatening complication of acute percutaneous coronary intervention (PCI) for chronic total occlusions (CTO), but data on midterm outcomes are limited. Methods and Results Data from LATAM (Latin American)-CTO Registry (57 centers; 9 countries) were analyzed. We assessed the risk of 30-day, 1-year major adverse cardiac events of coronary perforation using time-to-event and weighted composite end point analysis having CTO PCI without perforation as comparators. Additionally, we studied the independent predictors of perforation in these patients. Of 2054 patients who underwent CTO PCI between 2015 and 2018, the median Multicenter CTO Registry in Japan and Prospective Global Registry for the Study of Chronic Total Occlusion Intervention-Chronic total occlusions scores were 2.0 (1.0-3.0) and 1.0 (0.0-2.0), respectively. The perforation rate was 3.7%, of which 55% were Ellis class 1. After 1-year coronary perforation had higher major adverse cardiac events rates (24.9% versus 13.3%; P<0.01). Using weighted composite end point, perforation was associated with increased bleeding and ischemic events at 6 months (P=0.04) and 1 year (P<0.01). We found as independent predictors associated with coronary perforation during CTO PCI: maximum activated clotting time (P<0.01), Multicenter CTO Registry in Japan score ≥2 (P=0.05), antegrade knuckle wire (P=0.04), and right coronary artery CTO PCI (P=0.05). Conclusions Coronary perforation was infrequent and associated with anatomical and procedural complexity, resulting in higher risk of hemorrhagic and ischemic events. Landmark and weighted analysis showed a sustained burden of major events between 6 months and 1 year follow-up.

Treatment of knee osteoarthritis with a new formulation of a fixed-dose combination of glucosamine sulfate and bovine chondroitin: a multicenter, randomized, single-blind, non-inferiority clinical trial.

OBJECTIVES: To compare the efficacy and safety of a new formulation of a fixed dose combination of glucosamine sulfate (GS; 1500 mg) and bovine chondroitin sulfate (CS; 1200 mg) versus the reference product (RP) in patients with knee osteoarthritis (OA). METHODS: In this multicenter, randomized, single-blind trial, 627 patients with knee osteoarthritis (OA)-Kellgren-Lawrence grades 2 or 3 and mean score ≥ 40 mm in the WOMAC pain subscale-were randomized to receive GS/CS or the RP for 24 weeks. The primary efficacy endpoint was the absolute change in WOMAC pain subscale score. The secondary endpoints included the following: WOMAC total and subscale scores, overall assessment of the disease by the patient and the investigator, SF-12 score, OMERACT-OARSI response rate to the treatment, and rescue medication use. RESULTS: Mean reductions of WOMAC pain score were - 35.1 (sd = 23.2) mm in the GS/CS group and - 36.5 (sd = 24.9) mm in the RP group. The difference between the adjusted means of both treatments confirmed the non-inferiority of GS/CS versus the RP. Improvement was observed in pain, stiffness, physical function and total WOMAC score, as well as in overall OA assessment by the patient and the investigator for both groups. No improvement was observed in SF-12. The rate of OMERACT-OARSI responders was 89.4% in GS/CS group and 87.9% in the RP group. Headache and changes in glucose tolerance were the most frequent treatment-related adverse events. CONCLUSIONS: The new formulation of a fixed-dose combination of glucosamine sulfate and bovine chondroitin sulfate was non-inferior to the RP in symptomatic treatment of knee OA, with a high responder rate and good tolerability profile. TRIAL REGISTRATION: ClinicalTrials.gov; Registration number NCT02830919 ; Date of registration: July 13, 2016; First randomization date: December 05, 2016).

In-stent chronic total occlusion angioplasty in the LATAM-CTO registry.

OBJECTIVES: To inform about contemporary PCI practice of in-stent (IS) chronic total occlusions (CTO) from a large international registry in Latin America. BACKGROUND: IS-CTO represent a distinctive challenge for PCI, but literature is limited and restricted to high-resource regions of the world. METHODS: Patients undergoing CTO PCI enrolled in the LATAM CTO registry from 42 centers in eight countries were included. We analyzed demographics, angiographic, procedure technique, success and postprocedural outcomes between IS-CTO and non-IS-CTO PCI. RESULTS: From 1,565 patients IS-CTO was present in 181 patients (11.5%). IS-CTO patients had higher prevalence of diabetes and hypertension than patients without IS-CTO. IS-CTOs had less calcification (32.5 vs. 46.7%, p < .001), lower prevalence of a proximal branch (36.3 vs. 50.1%, p < .001), more likely to be ostial (24.4 vs. 18.1%, p = .042), were longer (28.5 vs. 25.2 mm, p = .062), and had less interventional collaterals (49.1 vs. 57.3%, p = .038) compared with non-IS-CTO. CTO complexity scores were similar between both groups. There was no statistically significant difference in the initial or successful strategy between IS-CTO and non-IS-CTO PCI. Technical success rates remained high in IS-CTO (86.7%) and non-IS-CTO (83.1%, p = .230). There was no independent association between IS-CTO and technical success in multivariable analysis. There were no differences between IS-CTO and non-IS-CTO groups for in-hospital clinical outcomes. CONCLUSION: In a contemporary, multicenter, and international registry from Latin America, IS-CTO PCI is frequent and has comparable technical success and safety profile compared to non-IS-CTO PCI.

Vacuumed collagen-impregnated bioglass scaffolds: Characterization and influence on proliferation and differentiation of bone marrow stromal cells.

This study evaluated physical-chemical characteristics of a vacuumed collagen-impregnated bioglass (BG) scaffolds and bone marrow stromal cells (BMSCs) behavior on those composites. scanning electron microscope and energy dispersive x-ray spectroscope demonstrated collagen (Col) was successfully introduced into BG. Vacuum impregnation system has showed efficiency for Col impregnation in BG scaffolds (approximately 20 wt %). Furthermore, mass weight decreasing and more stabilized pH were observed over time for BG/Col upon incubation in phosphate buffered saline compared to plain BG under same conditions. Calcium evaluation (Ca assay) demonstrated higher calcium uptake for BG/Col samples compared to BG. In addition, BG samples presented hydroxyapatite crystals formation on its surface after 14 days in simulated body fluid solution, and signs of initial degradation were observed for BG and BG/Col after 21 days. Fourier transform infrared spectroscopy spectra for both groups indicated peaks for hydroxyapatite formation. Finally, a significant increase of BMSCs viability for both composites was observed compared to control group, but no increase of osteogenic differentiation-related gene expressions were found. In summary, BG/Col scaffolds have improved degradation, pH equilibrium and Ca mineralization over time, accompanied by hydroxyapatite formation. Moreover, both BG and BG/Col scaffolds were biocompatible and noncytotoxic, promoting a higher cell viability compared to control. Future investigations should focus on additional molecular and in vivo studies in order to evaluate biomaterial performance for bone tissue engineering applications. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 211-222, 2019.

Amorphous calcium phosphate (ACP) in tissue repair process.

Synthetic biomaterials submitted to new structural technologies have become ideal for the recovery of traumatized bone tissues and some bone substitutes such as bioactive glass, ß-Tricalcium phosphate (ß-TCP) and amorphous calcium phosphate (ACP) are being used in areas of tissue defects. For this study, ACP was produced in the form of fibers and then submitted to cytotoxicity testing. A sample of ACP was inserted into the mandibular region of a patient with a lost implant so after removal and curettage, the remaining bone site was filled with the ACP biomaterial. Preliminary cytotoxicity test was negative. After 15 weeks of healing, a titanium implant was inserted at the site. Clinical and radiographic follow-up was conducted for 12 months and sequential radiographic analyses revealed tissue formation resembling spongy bone. Images under immunohistochemistry demonstrated efficient deposition and osteoconduction of the newly deposited tissue. Residual portion of the CaO:P2 O5 outer layers served as a substrate for osteoid matrix deposition, aiding growth, and the results of fiber absorption favored maturation of the new bone tissue.

The effects of preventive rubber band training on shoulder joint imbalance and throwing performance in handball players: A randomized and prospective study.

OBJECTIVES: To investigate the effects of a strength training program (STP) using rubber band exercises. METHODS: Twenty-five athletes were divided into two groups: muscular imbalance in the dominant (D) and in the non-dominant (ND) upper limbs. Each group was subdivided into experimental and control groups. Experimental groups performed eighteen sessions of STP. Athletes were submitted to ball throwing and isokinetic strength tests to assess the muscular strength of the shoulder rotator muscles and conventional and functional balance ratios. RESULTS: STP improved external rotator peak torque (18.0 ± 0.8 to 21.3 ± 1.0 Nm, p < 0.01) and total work (29.3 ± 0.9 to 34.5 ± 1.5 J, p < 0.01) in the D experimental group, while only total work (34.8 ± 2.5 to 37.6 ± 3.1 J, p < 0.03) improved in the D control group. The ND experimental group also presented significant improvement in external rotator peak torque (18.8 ± 0.8 to 21.1 ± 1.3 Nm, p < 0.01) and total work values (29.0 ± 1.4 to 34.6 to 1.6 J, p < 0.01) while there was no strength improvement in the ND control group. The ND experimental group showed an improvement in conventional (61.5 ± 3.5 to 72.7 ± 3.0%, p = 0.03) and functional (1.0 ± 0.1 to 1.6 ± 0.08, p < 0.01) ratios. STP did not improve the conventional ratio in the D experimental group. However, STP produced a large effect size. The D experimental group presented an improvement in ball velocity (49.0 ± 2.4 to 52.5 ± 2.2 km/h, p = 0.04) in standing position throwing. CONCLUSIONS: STP improves muscular strength of external rotator muscles and muscular balance.

Strength Training Using Elastic Bands: Improvement of Muscle Power and Throwing Performance in Young Female Handball Players.

CONTEXT: Imbalance in shoulder-rotator muscles has been considered a risk factor for injuries in handball. Strength training programs (STPs) may play an important preventive role. OBJECTIVE: To verify the effects of an STP using elastic bands on shoulder muscles and ball-throwing speed. DESIGN: Randomized and prospective controlled trial. SETTING: Exercise physiology laboratory. PARTICIPANTS: Thirty-nine female handball players were randomly assigned to an experimental (EG, n = 21, 15.3 ± 1.1 y) or a control (CG, n = 18, 15.0 ± 0.8 y) group. INTERVENTION: The EG performed the STP with elastic-band progressive exercises for 6 wk before regular handball training, and the CG underwent only their regular training. MAIN OUTCOME MEASURES: Before and after the STP, both groups underwent a ball-throwing-speed test and isokinetic test to assess shoulder internal- (IR) and external-rotator muscle performance. RESULTS: Average power values for IR muscles presented a significant group-vs-time interaction effect (F = 3.9, P = .05); EG presented significantly higher values after the STP (P = .03). Ball speed presented higher values in EG after the STP in standing (P = .04) and jumping (P = .03) throws. IR peak-torque values and balance in shoulder-rotator muscles presented no group-vs-time interaction effect. CONCLUSIONS: STP using elastic bands performed for 6 wk was effective to improve muscle power and ball speed for young female handball players.

Calcium phosphate fibers coated with collagen: In vivo evaluation of the effects on bone repair.

The aim of this study was to assess the characteristics of the CaP/Col composites, in powder and fiber form, via scanning electron microscopy (SEM), pH and calcium release evaluation after immersion in SBF and to evaluate the performance of these materials on the bone repair process in a tibial bone defect model. For this, four different formulations (CaP powder - CaPp, CaP powder with collagen - CaPp/Col, CaP fibers - CaPf and CaP fibers with collagen - CaPf/Col) were developed. SEM images indicated that both material forms were successfully coated with collagen and that CaPp and CaPf presented HCA precursor crystals on their surface. Although presenting different forms, FTIR analysis indicated that CaPp and CaPf maintained the characteristic peaks for this class of material. Additionally, the calcium assay study demonstrated a higher Ca uptake for CaPp compared to CaPf for up to 5 days. Furthermore, pH measurements revealed that the collagen coating prevented the acidification of the medium, leading to higher pH values for CaPp/Col and CaPf/Col. The histological analysis showed that CaPf/Col demonstrated a higher amount of newly formed bone in the region of the defect and a reduced presence of material. In summary, the results indicated that the fibrous CaP enriched with the organic part (collagen) glassy scaffold presented good degradability and bone-forming properties and also supported Runx2 and RANKL expression. These results show that the present CaP/Col fibrous composite may be used as a bone graft for inducing bone repair.

Ischemic Preconditioning and Repeated Sprint Swimming: A Placebo and Nocebo Study.

PURPOSE: Ischemic preconditioning (IPC) has been shown to improve performance of exercises lasting 10-90 s (anaerobic) and more than 90 s (aerobic). However, its effect on repeated sprint performance has been controversial, placebo effect has not been adequately controlled, and nocebo effect has not been avoided. Thus, the IPC effect on repeated sprint performance was investigated using a swimming task and controlling placebo/nocebo effects. METHODS: Short-distance university swimmers were randomized to two groups. One group (n = 15, 24 ± 1 yr [mean ± SEM]) was exposed to IPC (ischemia cycles lasted 5 min) and control (CT) (no ischemia); another (n = 15, 24 ± 1 yr) to a placebo intervention (SHAM) (ischemia cycles lasted 1 min) and CT. Seven subjects crossed over groups. Subjects were informed IPC and SHAM would improve performance compared with CT and would be harmless despite circulatory occlusion sensations. The swimming task consisted of six 50-m all-out efforts repeated every 3 min. RESULTS: IPC, in contrast with SHAM, reduced worst sprint time (IPC, 35.21 ± 0.73 vs CT, 36.53 ± 0.72 s; P = 0.04) and total sprints time (IPC, 203.7 ± 4.60 vs CT, 206.03 ± 4.57 s; P = 0.02), moreover augmented swimming velocity (IPC, 1.45 ± 0.03 vs CT, 1.44 ± 0.03 m·s; P = 0.049). Six of seven subjects who crossed over groups reduced total sprints time with IPC versus SHAM (delta = -3.95 ± 1.49 s, P = 0.09). Both IPC and SHAM did not change blood lactate concentration (P = 0.20) and perceived effort (P = 0.22). CONCLUSION: IPC enhanced repeated sprint swimming performance in university swimmers, whereas a placebo intervention did not.

Effect of fatigue caused by a simulated handball game on ball throwing velocity, shoulder muscle strength and balance ratio: a prospective study.

BACKGROUND: Arm throwing represents a deciding element in handball. Ball velocity, aim accuracy, and dynamic stability of the shoulder are factors that influence throwing effectiveness. The purpose of this study was to examine the influence of muscle fatigue caused by simulated game activities (SGA) on shoulder rotational isokinetic muscle strength, muscle balance and throwing performance, and to examine the relationship between muscle strength and throwing performance. METHODS: Ten national elite adult handball athletes were evaluated. Isokinetic internal (IR), external (ER) rotators peak torque, and balance ratio were measured before and after SGA. Ball throwing velocity was assessed by radar gun. RESULTS: Both internal (IR) and external (ER) rotators peak torque were significantly lower after SGA (p = 0.0003 and p = 0.02, respectively). However, the deleterious effect was more evident for IR than ER muscles (effect size r = 0.39 and r = 0.18, respectively). Balance ratio before and after SGA did not differ (p = 0.06). Ball throwing velocity was not impaired by SGA. Moreover, isokinetic variables correlated positively with ball velocity (r ≥ 0.67). CONCLUSIONS: SGA affected the muscle strength of IR more than ER, predisposing the shoulder joint to muscular imbalance. The muscular impairment after SGA was insufficient to impair ball throwing velocity.

Assessment of functional impairment after knee anterior cruciate ligament reconstruction using cardiorespiratory parameters: a cross-sectional study.

BACKGROUND: A dynamic sub-maximum exercise with the same absolute intensity, performed with different muscle groups, may present exacerbated cardiorespiratory responses. Therefore, cardiorespiratory responses to unilateral exercise may identify bilateral differences. The purpose of this study was to verify whether the cardiorespiratory responses to lower limb exercise display counter-lateral differences, and if they could be used to assist athletes and health professionals involved in rehabilitation. METHODS: Nine individuals participated in this cross-sectional study. They had been treated in a private rehabilitation clinic and submitted to intra-articular reconstruction of the anterior cruciate ligament. The cycling exercise with the same sub-maximal intensity and with one lower limb was used to gather data. Cardiorespiratory responses to exercise were compared between exercises performed with the involved and uninvolved limb after five minutes of exercise. RESULTS: Cardiorespiratory responses to exercise performed with the involved limb presented higher values after five minutes of cycling: oxygen uptake (+7%), carbon dioxide production (+10%), minute ventilation (+20%), breathing frequency (+19%), ventilatory equivalent for oxygen (+14%), end-tidal pressure of O2 oxygen (+4%), end-tidal pressure of O2 carbon dioxide (-9%) and heart rate (+9%). CONCLUSIONS: The exacerbated responses, including increase of the ventilatory equivalent and decrease of end-tidal pressure of carbon dioxide, indicate that this exercise protocol may be useful in the characterization of the functional deficit of the surgical limb during rehabilitation.

Lung function in post-poliomyelitis syndrome: a cross-sectional study.

OBJECTIVE: To compare lung function between patients with post-poliomyelitis syndrome and those with sequelae of paralytic poliomyelitis (without any signs or symptoms of post-poliomyelitis syndrome), as well as between patients with post-poliomyelitis syndrome and healthy controls. METHODS: Twenty-nine male participants were assigned to one of three groups: control; poliomyelitis (comprising patients who had had paralytic poliomyelitis but had not developed post-poliomyelitis syndrome); and post-poliomyelitis syndrome. Volunteers underwent lung function measurements (spirometry and respiratory muscle strength assessment). RESULTS: The results of the spirometric assessment revealed no significant differences among the groups except for an approximately 27% lower mean maximal voluntary ventilation in the post-poliomyelitis syndrome group when compared with the control group (p = 0.0127). Nevertheless, the maximal voluntary ventilation values for the post-poliomyelitis group were compared with those for the Brazilian population and were found to be normal. No significant differences were observed in respiratory muscle strength among the groups. CONCLUSIONS: With the exception of lower maximal voluntary ventilation, there was no significant lung function impairment in outpatients diagnosed with post-poliomyelitis syndrome when compared with healthy subjects and with patients with sequelae of poliomyelitis without post-poliomyelitis syndrome. This is an important clinical finding because it shows that patients with post-poliomyelitis syndrome can have preserved lung function.

Profiling the isokinetic shoulder rotator muscle strength in 13- to 36-year-old male and female handball players.

OBJECTIVES: To evaluate the external (ER) and internal rotator (IR) muscles' isokinetic peak torque and conventional and functional strength ratios in handball players and controls of different ages. DESIGN: Cross-sectional and descriptive analysis. SETTING: Exercise Physiology Laboratory. PARTICIPANTS: A total of 228 participants (108 athletes and 120 controls) were divided into five groups according to age, ranging from 13 to 36 years old. MAIN OUTCOME MEASURES: Isokinetic tests were performed concentrically at 60 and 300 deg s(-1) and eccentrically at 300 deg s(-1). RESULTS: The differences between the athletes and controls regarding the peak torque of the ER and IR muscles were significant in males older than 18 years. The peak torque of the IR and ER muscles increased significantly across age in male athletes, but not in female athletes, except in the case of ER peak torque, which differed significantly between 13 and 16 years old. The female athletes presented higher conventional ratios (0.81 ± 0.07) than males (0.66 ± 0.08). Values represent means and standard deviations. Athletes and controls showed mean functional strength ratios below 1.0. CONCLUSIONS: Although there were no muscular ratio differences between the athletes and the controls, their ratio values were below the literature-recommended reference values to prevent shoulder injuries.

Heart rate response during a simulated Olympic boxing match is predominantly above ventilatory threshold 2: a cross sectional study.

The present study aimed to describe heart rate (HR) responses during a simulated Olympic boxing match and examine physiological parameters of boxing athletes. Ten highly trained Olympic boxing athletes (six men and four women) performed a maximal graded exercise test on a motorized treadmill to determine maximal oxygen uptake (52.2 mL · kg(-1) · min(-1) ± 7.2 mL · kg(-1) · min(-1)) and ventilatory thresholds 1 and 2. Ventilatory thresholds 1 and 2 were used to classify the intensity of exercise based on respective HR during a boxing match. In addition, oxygen uptake (V̇O2) was estimated during the match based on the HR response and the HR-V̇O2 relationship obtained from a maximal graded exercise test for each participant. On a separate day, participants performed a boxing match lasting three rounds, 2 minutes each, with a 1-minute recovery period between each round, during which HR was measured. In this context, HR and V̇O2 were above ventilatory threshold 2 during 219.8 seconds ± 67.4 seconds. There was an increase in HR and V̇O2 as a function of round (round 3 < round 2 < round 1, P < 0.0001). These findings may direct individual training programs for boxing practitioners and other athletes.

Dealing with water deficit in Atta ant colonies: large ants scout for water while small ants transport it.

Leafcutter ants (Atta sexdens rubropilosa) (Forel 1908) have an elaborate social organization, complete with caste divisions. Activities carried out by specialist groups contribute to the overall success and survival of the colony when it is confronted with environmental challenges such as dehydration. Ants detect variations in humidity inside the nest and react by activating several types of behavior that enhance water uptake and decrease water loss, but it is not clear whether or not a single caste collects water regardless of the cost of bringing this resource back to the colony. Accordingly, we investigated water collection activities in three colonies of Atta sexdens rubropilosa experimentally exposed to water stress. Specifically, we analyzed whether or not the same ant caste foraged for water, regardless of the absolute energetic cost (distance) of transporting this resource back to the colony. Our experimental design offered water sources at 0 m, 1 m and 10 m from the nest. We studied the body size of ants near the water sources from the initial offer of water (time  =  0) to 120 min, and tested for specialization. We observed a reduction in the average size and variance of ants that corroborated the specialization hypothesis. Although the temporal course of specialization changed with distance, the final outcome was similar among distances. Thus, we conclude that, for this species, a specialist (our use of the word "specialist" does not mean exclusive) task force is responsible for collecting water, regardless of the cost of transporting water back to the colony.

Isokinetic hamstrings-to-quadriceps peak torque ratio: the influence of sport modality, gender, and angular velocity.

The purpose of this study was to determine differences in hamstrings-to-quadriceps (H/Q) peak torque ratios evaluated at different angular velocities between men and women who participate in judo, handball or soccer. A total of 166 athletes, including 58 judokas (26 females and 32 males), 39 handball players (22 females and 17 males), and 69 soccer players (17 females and 52 males), were evaluated using an isokinetic dynamometer. The H/Q isokinetic peak torque ratios were calculated at angular velocities of 1.05 rad · s⁻¹ and 5.23 rad · s⁻¹. In the analysis by gender, female soccer players produced lower H/Q peak torque ratios at 1.05 rad · s⁻¹ than males involved in the same sport. However, when H/Q peak torque ratio was assessed at 5.23 rad · s⁻¹, there were no significant differences between the sexes. In the analysis by sport, there were no differences among females at 1.05 rad · s⁻¹. In contrast, male soccer players had significantly higher H/Q peak torque ratios than judokas (66 ± 12% vs. 57 ± 14%, respectively). Female handball players produced significantly lower peak torque ratios at 5.23 rad · s⁻¹ than judokas or soccer players, whereas males presented no ratio differences among sports At 5.23 rad · s⁻¹. In the analysis by velocity, women's muscular ratios assessed at 1.05 rad · s⁻¹ were significantly lower than at 5.23 rad · s⁻¹ for all sports; among men, only judokas presented lower ratios at 1.05 rad · s⁻¹ than at 5.23 rad · s⁻¹. The present results suggest that sport modality and angular velocity influence the isokinetic strength profiles of men and women.