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The development of new methods of identification of active pharmaceutical ingredients (API) is a subject of paramount importance for research centers, the pharmaceutical industry, and law enforcement agencies. Here, a system for identifying and classifying pharmaceutical tablets containing acetaminophen (AAP) by brand has been developed. In total, 15 tablets of 11 brands for a total of 165 samples were analyzed. Mid-infrared vibrational spectroscopy with multivariate analysis was employed. Quantum cascade lasers (QCLs) were used as mid-infrared sources. IR spectra in the spectral range 980-1600 cm-1 were recorded. Five different classification methods were used. First, a spectral search through correlation indices. Second, machine learning algorithms such as principal component analysis (PCA), support vector classification (SVC), decision tree classifier (DTC), and artificial neural network (ANN) were employed to classify tablets by brands. SNV and first derivative were used as preprocessing to improve the spectral information. Precision, recall, specificity, F1-score, and accuracy were used as criteria to evaluate the best SVC, DEE, and ANN classification models obtained. The IR spectra of the tablets show characteristic vibrational signals of AAP and other APIs present. Spectral classification by spectral search and PCA showed limitations in differentiating between brands, particularly for tablets containing AAP as the only API. Machine learning models, specifically SVC, achieved high accuracy in classifying AAP tablets according to their brand, even for brands containing only AAP.
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Acetaminofen , Aprendizado de Máquina , Análise de Componente Principal , Espectrofotometria Infravermelho , Comprimidos , Acetaminofen/química , Acetaminofen/análise , Comprimidos/química , Espectrofotometria Infravermelho/métodos , Redes Neurais de Computação , Algoritmos , Máquina de Vetores de SuporteRESUMO
BACKGROUND: More than 90% of the morbidity and mortality from chronic respiratory disease occurs in low-income and middle-income countries (LMICs), with substantial economic impact. Preserved ratio impaired spirometry (PRISm) is a prevalent lung function abnormality associated with increased mortality in high-income countries. We aimed to conduct a post-hoc analysis of a cross-sectional study to assess the prevalence of, the risk factors for, and the impact of PRISm in three diverse LMIC settings. METHODS: We recruited a random, age-stratified and sex-stratified sample of the population in semi-urban Bhaktapur, Nepal; urban Lima, Peru; and rural Nakaseke, Uganda. Quality-assured post-bronchodilator spirometry was performed to American Thoracic Society standards and PRISm was defined as a forced expiratory volume in one second (FEV1) of less than 80% predicted with a FEV1/forced vital capacity ratio of 0·70 or more. We used t tests and χ2 analyses to assess the relationships between demographic, biometric, and comorbidity variables with PRISm. Multivariable logistic models with random intercept by site were used to estimate odds ratios (ORs) with 95% CIs. FINDINGS: 10â664 participants were included in the analysis, with a mean (SD) age of 56·3 (11·7) years and an equal distribution by sex. The prevalence of PRISm was 2·5% in Peru, 9·1% in Nepal, and 16·0% in Uganda. In multivariable analysis, younger age (OR for each decile of age 0·87, 95% CI 0·82-0·92) and being female (1·37, 1·18-1·58) were associated with increased odds of having PRISm. Biomass exposure was not consistently associated with PRISm across sites. Individuals with PRISm had impairment in respiratory-related quality of life as measured by the St George's Respiratory Questionnaire (OR by decile 1·18, 95% CI 1·10-1·25). INTERPRETATION: The prevalence of PRISm is heterogeneous across LMIC settings and associated with age, female sex, and biomass exposure, a common exposure in LMICs. A diagnosis of PRISm was associated with worse health status when compared with those with normal lung function. Health systems in LMICs should focus on all spirometric abnormalities as opposed to obstruction alone, given the disease burden, reduced quality of life, and size of the undiagnosed population at risk. FUNDING: Medical Research Council.
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Países em Desenvolvimento , Espirometria , Humanos , Estudos Transversais , Feminino , Masculino , Prevalência , Adulto , Pessoa de Meia-Idade , Países em Desenvolvimento/estatística & dados numéricos , Peru/epidemiologia , Nepal/epidemiologia , Uganda/epidemiologia , Volume Expiratório Forçado , Idoso , Fatores de Risco , Adulto JovemRESUMO
In this study, the impact of ethylene oxide, propylene oxide, 1,2-butene oxide, and 1,2-pentene oxide on the polymerization of propylene at an industrial level was investigated, focusing on their influence on the catalytic efficiency and the properties of polypropylene (PP) without additives. The results show that concentrations between 0 and 1.24 ppm of these epoxides negatively affect the reaction's productivity, the PP's mechanical properties, the polymer's fluidity index, and the PP's thermal properties. Fourier transform infrared spectroscopy (FTIR) revealed bands for the Ti-O bond and the Cl-Ti-O-CH2 bonds at 430 to 475 cm-1 and 957 to 1037 cm-1, respectively, indicating the interaction between the epoxides and the Ziegler-Natta catalyst. The thermal degradation of PP in the presence of these epoxides showed a similar trend, varying in magnitude depending on the concentration of the inhibitor. Sample M7, with 0.021 ppm propylene oxide, exhibited significant mass loss at both 540 °C and 600 °C, suggesting that even small concentrations of this epoxide can markedly increase the thermal degradation of PP. This pattern is repeated in samples with 1,2-butene oxide and 1,2-pentene oxide. These results highlight the need to strictly control the presence of impurities in PP production to optimize both the final product's quality and the polymerization process's efficiency.
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Background: NovoSorb biodegradable temporizing matrix (BTM) is a novel, bilayer, synthetic skin substitute made of biodegradable polyurethane foam covered with a sealing membrane. BTM has demonstrated excellent outcomes in burn literature; however, few studies have been published for hand and extremity soft tissue reconstruction. Methods: All patients who underwent extremity reconstruction with BTM from 2018 to 2023 were reviewed. Demographics, presentations, and clinical outcomes were recorded. Results: A total of 86 cases from 54 patients (53.7% pediatric; age range: 0-81 years) were included. Common indications included trauma (36%), infection (18.6%), and malignancy (11.6%). BTM was placed over exposed tendon (38.4%), bone (19%), joints (12.8%), nerves (8.1%), and/or blood vessels (7%). BTM served as temporary wound coverage in 26 cases. Complications included hematoma (8.1%), infection (4.7%), and spontaneous delamination (4.7%). Wound closure was successfully obtained without flap use in 93.3%. Poor BTM take was associated with peripheral vascular disease, hypertension, immunosuppression, and BTM hematoma and infection (<0.05). Conclusion: This study contributes to the growing body of evidence favoring BTM use in challenging reconstructive cases. Although prospective comparative studies are forthcoming, BTM likely has broad applications in reconstructive surgery.
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OBJECTIVES: To derive systematic-review informed, modified Delphi consensus regarding the influence of extracorporeal membrane oxygenation (ECMO) circuit components on anticoagulation practices for pediatric ECMO for the Pediatric ECMO Anticoagulation CollaborativE. DATA SOURCES: A structured literature search was performed using PubMed, EMBASE, and Cochrane Library (CENTRAL) databases from January 1988 to May 2021. STUDY SELECTION: Management of ECMO anticoagulation in the setting of different ECMO circuit components. DATA EXTRACTION: Two authors reviewed all citations independently, with a third independent reviewer resolving conflicts. Twenty-nine references were used for data extraction and informed recommendations, evidence-based consensus statements, and good practice statements. Evidence tables were constructed using a standardized data extraction form. DATA SYNTHESIS: Risk of bias was assessed using the Quality in Prognosis Studies tool. The evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation system. Forty-eight experts met over 2 years to develop evidence-based recommendations and, when evidence was lacking, expert-based consensus statements or good practice statements for the influence of ECMO circuit and components on anticoagulation management. A web-based modified Delphi process was used to build consensus via the Research And Development/University of California Appropriateness Method. Consensus was defined as greater than 80% agreement. One good practice statement, 2 weak recommendations, and 2 consensus statements are presented. CONCLUSIONS: The incorporation of new component technologies into clinical practice has outpaced clinical investigations of anticoagulation strategies for pediatric ECMO. Future investigations should leverage academic and industrial collaborations, translational platforms, and modern biostatistical methods to improve patient outcomes.
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Anticoagulantes , Técnica Delphi , Oxigenação por Membrana Extracorpórea , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Criança , ConsensoRESUMO
Purpose: This review aimed to compare the postoperative outcomes of open reduction internal fixation (ORIF) versus excision in the surgical treatment of hook of hamate fractures. Methods: A systematic review of PubMed and EMBASE databases from 1954 to 2023 was performed using the search term "hook of hamate fracture" to identify all publications regarding the use of ORIF or excision in the treatment of hook of hamate fractures. Outcomes included a return to sport, pain, ulnar nerve dysfunction, flexor tendon dysfunction, union rate, wrist range of motion (ROM; % of contralateral hand), grip strength (% of contralateral hand), and quick disabilities of arm, shoulder, and hand scores. Results: Twenty-seven of the 705 total screened articles were included. Excision of the hook of hamate (n = 779) resulted in a shorter return to sport time (6 vs 7.8 weeks), lower rates of postoperative pain (6.1% vs 33.3%), higher rates of ulnar nerve sensory dysfunction (4.2% vs 0%), and higher rates of ulnar nerve motor dysfunction (1.5% vs 0%) relative to ORIF (n = 51). Chronic fractures had a longer return to sport time (7.2 vs 5.7 weeks) relative to nonchronic injuries. Conclusions: Both surgical procedures appear to yield acceptable outcomes in the treatment of hook of hamate fractures. However, based on the sparsity of available data, we are unable to determine a consistent difference between hook of hamate excision and ORIF. Clinical relevance: To our knowledge, no current consensus on the optimal surgical treatment for hook of hamate fractures exists. Our findings emphasize the need for a large prospective cohort study using standardized outcomes to provide strong evidence as to whether surgical excision or ORIF yields greater outcomes in the treatment of hook of hamate fractures.
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Riojasuchus tenuisceps was a pseudosuchian archosaur from the Late Triassic period in Argentina. Like other ornithosuchids, it had unusual morphology such as a unique "crocodile-reversed" ankle joint, a lesser trochanter as in dinosaurs and a few other archosaurs, robust vertebrae, and somewhat shortened, gracile forelimbs. Such traits have fuelled controversies about its locomotor function-were its limbs erect or "semi-erect"? Was it quadrupedal or bipedal, or a mixture thereof? These controversies seem to persist because analyses have been qualitative (functional morphology) or correlative (morphometrics) rather than explicitly, quantitatively testing mechanistic hypotheses about locomotor function. Here, we develop a 3D whole-body model of R. tenuisceps with the musculoskeletal apparatus of the hindlimbs represented in detail using a new muscle reconstruction. We use this model to quantify the body dimensions and hindlimb muscle leverages of this enigmatic taxon, and to estimate joint ranges of motion and qualitative joint functions. Our model supports prior arguments that R. tenuisceps used an erect posture, parasagittal gait and plantigrade pes. However, some of our inferences illuminate the rather contradictory nature of evidence from the musculoskeletal system of R. tenuisceps-different features support (or are ambiguous regarding) quadrupedalism or bipedalism. Deeper analyses of our biomechanical model could move toward a consensus regarding ornithosuchid locomotion. Answering these questions would not only help understand the palaeobiology and bizarre morphology of this clade, but also more broadly if (or how) locomotor abilities played a role in the survival versus extinction of various archosaur lineages during the end-Triassic mass extinction event.
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This study introduces a novel application of the Osteochondral Autograft Transfer System (OATS) for autologous bone grafting during alveolar cleft repair. Approximately 75% of patients with cleft lip and palate have an alveolar cleft, which often necessitates secondary bone grafting from common donor sites such as the iliac crest. Traditional harvesting techniques, although effective, can be labor-intensive and increase the risk of donor site injury. Here the authors describe the use of OATS, which has primarily been used in orthopedic procedures like anterior cruciate ligament reconstruction, for the first time in alveolar cleft repair. It involves a minimally invasive, single-use transfer system for harvesting osteochondral autografts from the anterior iliac crest, and thereby reduces harvest time compared with traditional open approaches. The procedure is detailed from pre-operative evaluation through long-term follow-up and highlights the technique's benefits related to surgical time, ease of use, and maintenance of sizable autograft volumes. Similarly, the authors discuss other advantages of OATS, including its single-use and cordless nature, which is believed to contribute to a lower contamination risk and better intraoperative ergonomics.
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BACKGROUND: The liver is the most common organ injured in blunt abdominal trauma and makes up roughly 5% of all trauma admissions. Current treatments are invasive and resource-intensive, which may delay care. We aim to develop and validate a contrast-enhanced ultrasound (CEUS)guided noninvasive tool to treat liver lacerations at the bedside. METHODS: Two 1.8 MHz high-intensity focused ultrasound (HIFU) elements were coupled to a C1-6 diagnostic ultrasound probe and a Logiq E10 scanner (GE HealthCare) utilizing a custom enclosure for co-registered imaging and ablation. A phantom was created from polyacrylamide gel combined with thermochromic ink whose color changes above biological ablative temperatures (60 °C). The HIFU wave was focused approximately 0.5 cm below the surface utilizing a 50% duty cycle generating 11.9 MPa for 20, 30, 40, 50, and 60s. Experiments were repeated on ex vivo chicken livers in a water bath. Finally, the livers of 4 live swine underwent up to 6 CEUS-guided treatments using parameters optimized from in vitro work. RESULTS: Treatment of the phantom between 20-60s, produced ablation sizes from 0.016 to 0.4 cm 3 . The relationship between time and size was exponential (R 2 = 0.992). Ablation areas were also well visualized on with ultrasound imaging. The ex vivo liver ablation size at 20s was 0.37 cm 3 , at 30s was 0.66 cm 3 , and at 100 s was 5.0 cm 3 . For the in-vivo swine experiments, the average ablation area measured 2.0x0.75 cm with a maximum of 3.5x1.5 cm. CEUS was utilized with the contrast agent Definity (Lantheus) for identification of lacerations as well as immediate post operative evaluation of therapy. CONCLUSION: These experiments demonstrate the feasibility of CEUS guided transdermal HIFU ablation and the time-dependent size of ablation. This work warrants future investigations into using ultrasound to detect active bleeding and HIFU to coagulate grade III and IV liver laceration. STUDY TYPE: Therapeutic/care management.
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Background: The co-occurrence of chronic diseases and acute infectious events exacerbates disability and diminishes quality of life, yet research in Low- and Middle-Income countries is scarce. We aimed to investigate the relationship between infectious events and multimorbidity in resource-constrained settings. Methods: We conducted a sequential mixed-method study in Lima and Tumbes, Peru, with participants having multimorbidity from the CRONICAS Cohort Study. They completed a questionnaire on the occurrence, treatment, and health-seeking behaviour related to acute infectious events. Qualitative interviews explored the perceptions and links between multimorbidity and acute infectious events for a subgroup of participants. Findings: Among individuals with multimorbidity, low awareness of chronic conditions and poor medication adherence. The cumulative incidence for respiratory and gastrointestinal infections, the most reported acute conditions, was 2.0 [95%CI: 1.8-2.2] and 1.6 [1.2-1.9] events per person per year, respectively. Individuals with cancer (6.4 [1.6-11.2] events per person per year) or gastrointestinal reflux (7.2 [4.4-10.1] events per person per year) reported higher cumulative incidence of infectious events than others, such as those with cardiovascular and metabolic conditions (5.2 [4.6-5.8] events per person per year). Those with three or more chronic conditions had a slightly higher cumulative incidence compared with individuals with two conditions (5.7 [4.4-7.0] vs 5.0 [4.4-5.6] events per person per year). Around 40% of individuals with multimorbidity sought healthcare assistance, while others chose drugstores or didn't seek help. Our qualitative analysis showed diverse perceptions among participants regarding the connections between chronic and acute conditions. Those who recognized a connection emphasized the challenges in managing these interactions. Interpretation: Our study advances understanding of multimorbidity challenges in resource-limited settings, highlighting the impact of acute infections on patients' existing multimorbidity burden.
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This paper introduces CYCLOPS, an acquisition system developed to capture images and inertial measurement data of moving cyclists from a vehicle. The development of CYCLOPS addresses the need to acquire useful data for training machine learning models capable of predicting the motion intentions of cyclists on urban roads. Considering its application, it is a completely original development. The system consists of two devices. The first device is installed on the bicycle and is based on an electronic acquisition board comprising an inertial measurement unit (IMU), a microcontroller, and a transceiver for sending the cyclist's acceleration and orientation data to a vehicle. The second device is installed on the vehicle and uses the same board architecture to acquire the vehicle's accelerations and orientations, along with an RGB monocular camera. The data is stored in real-time in a laptop's drive for subsequent analysis and manipulation. The hardware architecture is presented in detail, including the designs to install the devices, for IMUs configuration, and software installation on the laptop. All design and software files required to develop the proposed system are available for download at: doi.org/10.17632/3yx5y8b7tm.1, licensed under the Open-source license CC BY 4.0.
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Purpose: Carpal tunnel syndrome is the most common compressive neuropathy. The diagnostic parameters currently used for the general adult population may not be valid in elderly or younger cohorts. The purpose of this study is to determine the diagnostic accuracy of nerve conduction studies (NCS) and ultrasound (US) in different age groups utilizing the 6-item Carpal tunnel syndrome (CTS) symptoms scale (CTS-6) as the reference standard. Methods: A retrospective database of patients who underwent US and NCS as part of the diagnostic work-up for suspected peripheral nerve compression was reviewed. Subjects were separated into three groups based on the median age of carpal tunnel syndrome patients (55 years of age) and two standard deviations (standard deviation 13.5 years) above and below the median. The young group was 28 years of age or less, the middle group was 29-71 years of age, and the old group was 72 years of age or greater. CTS-6 and Boston Carpal Tunnel Syndrome Questionnaire scores were recorded. Using CTS-6 as a reference standard, the sensitivity and specificity were calculated for NCS and US. Results: A total of 295 hands were included in the analysis with 23 hands in the young group and 24 hands in the old group. NCS showed 31% sensitivity and 100% specificity in the young group compared to 54% sensitivity and 90% specificity for US. NCS showed 94% sensitivity and 25% specificity in the old group compared to 81% sensitivity and 38% specificity for US. Overall accuracy for US and NCS was 66% for both tests when looking at all age groups. The accuracy in the young group was 70% for US and 61% for NCS, whereas the accuracy in the old group was 67% for US and 71% for NCS. Conclusions: US has comparable sensitivity and specificity to NCS in patients two or more standard deviations above or below the mean age for presentation of CTS. US may be more accurate in younger patients, although NCS limits the number of false positive tests. There remains a substantial amount of inaccuracy for both tests when using a validated clinical diagnostic tool (CTS-6) as the reference standard. Type of study/level of Evidence: Diagnostic IV.
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INTRODUCTION: Sarcopenia and sarcopenic obesity (SO) have emerged as significant contributors to negative health outcomes in the past decade. We aimed to estimate the prevalence of probable sarcopenia, sarcopenia, and SO in a community-dwelling population of 1151 adults aged ≥55 years in Lima, Peru. METHODS: This cross-sectional study was conducted between 2018 and 2020. Sarcopenia was defined as the presence of low muscle strength (LMS) and low muscle mass (LMM) according to European (EWGSOP2), US (FNIH) and Asian (AWGS2) guidelines. We measured muscle strength by maximum handgrip strength and muscle mass using bioelectrical impedance analyzer. SO was defined as a body mass index ≥ 30 kg/m2 and sarcopenia. RESULTS: The study participants had a mean age of 66.2 years (SD 7.1), age range between 60 to 92 years old, of which 621 (53.9%) were men. Among the sample, 41.7% were classified as obese (BMI ≥30.0 kg/m²). The prevalence of probable sarcopenia was estimated to be 22.7% (95%CI: 20.3-25.1) using the EWGSOP2 criteria and 27.8% (95%CI: 25.2-30.4) using the AWGS2 criteria. Sarcopenia prevalence, assessed using skeletal muscle index (SMI), was 5.7% (95%CI: 4.4-7.1) according to EWGSOP2 and 8.3% (95%CI: 6.7-9.9) using AWGS2 criteria. The prevalence of sarcopenia based on the FNIH criteria was 18.1% (95%CI: 15.8-20.3). The prevalence of SO, considering different sarcopenia definitions, ranged from 0.8% (95%CI: 0.3-1.3) to 5.0% (95%CI: 3.8-6.3). CONCLUSION: Our findings reveal substantial variation in the prevalence of sarcopenia and SO, underscoring the necessity for context-specific cut-off values. Although the prevalence of SO was relatively low, this result may be underestimated. Furthermore, the consistently high proportion of probable sarcopenia and sarcopenia point to a substantial public health burden.
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Sarcopenia , Adulto , Masculino , Humanos , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Feminino , Sarcopenia/epidemiologia , Vida Independente , Estudos Transversais , Peru/epidemiologia , Força da Mão/fisiologia , Obesidade/complicações , Obesidade/epidemiologia , PrevalênciaRESUMO
AIM: To evaluate the effect of metformin on cancer incidence in subjects with overweight/obesity and/or prediabetes/diabetes. MATERIALS AND METHODS: We searched MEDLINE, Embase and CENTRAL for randomized controlled trials (RCTs) in adults with overweight/obesity and/or prediabetes/diabetes that compared metformin to other interventions for ≥24 weeks. Independent reviewers selected and extracted data including population and intervention characteristics and new diagnoses of cancer. We used the RoB 2.0 risk-of-bias tool and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework to assess risk of bias and certainty of evidence. RESULTS: From 14 895 records after removal of duplicates, 27 trials were included, providing a total of 10 717 subjects in the metformin group and 10 003 in the control group, with 170 and 208 new cases of cancer, respectively. Using a random-effects model, the relative risk was 1.07 (95% confidence interval 0.87-1.31), with similar results in subgroup analyses by study duration or effect of control intervention on weight. Risk of bias in most studies was low, and no evidence of publication bias was found. Trial sequential analysis provided evidence that the cumulative sample size was large enough to exclude a significant effect of metformin on cancer incidence. CONCLUSIONS: Metformin did not reduce cancer incidence in RCTs involving subjects with overweight/obesity and/or prediabetes/diabetes.
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Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Metformina , Neoplasias , Obesidade , Estado Pré-Diabético , Metformina/uso terapêutico , Humanos , Neoplasias/prevenção & controle , Neoplasias/epidemiologia , Obesidade/complicações , Hipoglicemiantes/uso terapêutico , Estado Pré-Diabético/complicações , Estado Pré-Diabético/tratamento farmacológico , Estado Pré-Diabético/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , IncidênciaRESUMO
The blood pressure-lowering effect of aerobic training is preceded by improving cardiovascular autonomic control. We previously demonstrated that aerobic training conducted in the evening (ET) induces a greater decrease in blood pressure than morning training (MT). To study whether the greater blood pressure decrease after ET occurs through better cardiovascular autonomic regulation, this study aimed to compare MT versus ET on muscle sympathetic nerve activity (MSNA) and baroreflex sensitivity (BRS) in treated patients with hypertension. Elderly patients treated for hypertension were randomly allocated into MT (n = 12, 07.00-10.00 h) or ET (n = 11, 17.00-20.00 h) groups. Both groups trained for 10 weeks, 3 times/week, cycling for 45 min at moderate intensity. Beat-to-beat blood pressure (finger photoplethysmography), heart rate (electrocardiography) and MSNA (microneurography) were assessed at the initial and final phases of the study at baseline and during sequential bolus infusions of sodium nitroprusside and phenylephrine (modified-Oxford technique) to evaluate cardiac and sympathetic BRS. Mean blood pressure decreased significantly after ET but not after MT (-9 ± 11 vs. -1 ± 8 mmHg, P = 0.042). MSNA decreased significantly only after ET with no change after MT (-12 ± 5 vs. -3 ± 7 bursts/100 heart beats, P = 0.013). Sympathetic BRS improved after ET but not after MT (-0.8 ± 0.7 vs. 0.0 ± 0.8 bursts/100 heart beats/mmHg, P = 0.052). Cardiac BRS improved similarly in both groups (ET: +1.7 ± 1.8 vs. MT: +1.4 ± 1.9 ms/mmHg, Pphase ≤ 0.001). In elderly patients treated for hypertension, only ET decreased mean blood pressure and MSNA and improved sympathetic BRS. These findings revealed that the sympathetic nervous system has a key role in ET's superiority to MT in blood pressure-lowering effect. KEY POINTS: Reducing muscle nerve sympathetic activity and increasing sympathetic baroreflex sensitivity plays a key role in promoting the greater blood pressure reduction observed with evening training. These findings indicated that simply changing the timing of exercise training may offer additional benefits beyond antihypertensive medications, such as protection against sympathetic overdrive and loss of baroreflex sensitivity, independent markers of mortality. Our new findings also suggest new avenues of investigation, such as the possibility that evening aerobic training may be beneficial in other clinical conditions with sympathetic overdrive, such as congestive heart failure and hypertrophic cardiomyopathy.
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Sistema Cardiovascular , Hipertensão , Humanos , Idoso , Barorreflexo/fisiologia , Hipertensão/terapia , Pressão Sanguínea/fisiologia , Coração , Sistema Nervoso Simpático/fisiologia , Frequência Cardíaca/fisiologia , Músculo EsqueléticoRESUMO
Characterizing seasonal changes in diatom community profiles in coastal environments is scarce worldwide. Despite diatoms being prevalent in microfouling, their role in microbially influenced corrosion of metallic materials remains poorly understood. This study reports the effect of seasonal variations on the settlement of marine diatoms and corrosion of 316 L stainless steel surfaces exposed to Chilean coastal seawater. Electron microscopy imaging revealed a diverse assembly of diatoms, exhibiting pronounced differences at genus level between summer and winter seasons, with a significant delay in diatom settlement during winter. Electrochemical measurements indicated an active role of diatoms in increasing corrosion current during biofilm development. While the final diatom composition was similar irrespective of the season, the analyses of diatom assemblages over time differed, showing faster colonization when silicate and nitrate were available. This study lays the foundation for future research on the dominant season-specific genera of diatoms to unveil the microbial interactions that could contribute to corrosion and to evaluate their potential as bioindicators for alternative surveillance strategies.
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Diatomáceas , Estações do Ano , Aço Inoxidável/química , Chile , BiofilmesRESUMO
BACKGROUND: When feeding on a vertebrate host, ticks secrete saliva, which is a complex mixture of proteins, lipids, and other molecules. Tick saliva assists the vector in modulating host hemostasis, immunity, and tissue repair mechanisms. While helping the vector to feed, its saliva modifies the site where pathogens are inoculated and often facilitates the infection process. The objective of this study is to uncover the variation in protein composition of Rhipicephalus microplus saliva during blood feeding. METHODS: Ticks were fed on calves, and adult females were collected, weighed, and divided in nine weight groups, representing the slow and rapid feeding phases of blood feeding. Tick saliva was collected, and mass spectrometry analyses were used to identify differentially secreted proteins. Bioinformatic tools were employed to predict the structural and functional features of the salivary proteins. Reciprocal best hit analyses were used to identify conserved families of salivary proteins secreted by other tick species. RESULTS: Changes in the protein secretion profiles of R. microplus adult female saliva during the blood feeding were observed, characterizing the phenomenon known as "sialome switching." This observation validates the idea that the switch in protein expression may serve as a mechanism for evading host responses against tick feeding. Cattle tick saliva is predominantly rich in heme-binding proteins, secreted conserved proteins, lipocalins, and protease inhibitors, many of which are conserved and present in the saliva of other tick species. Additionally, another remarkable observation was the identification of host-derived proteins as a component of tick saliva. CONCLUSIONS: Overall, this study brings new insights to understanding the dynamics of the proteomic profile of tick saliva, which is an important component of tick feeding biology. The results presented here, along with the disclosed sequences, contribute to our understanding of tick feeding biology and might aid in the identification of new targets for the development of novel anti-tick methods.
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Rhipicephalus , Animais , Feminino , Bovinos , Rhipicephalus/fisiologia , Saliva/química , Proteômica , Proteínas de Artrópodes/metabolismo , Proteínas e Peptídeos Salivares/metabolismoRESUMO
Two experiments were conducted in the Northern (UK) and Southern (Brazil) hemispheres to determine the effect of season (month of conception) on the development of supplementary CL (SCL) and the relationship with pregnancy loss. In experiment 1, 199 pregnancies were followed between Day 14 and term, to determine the number of SCL and pregnancy viability (Northern Hemisphere). From the 199 pregnancies, 178 were obtained from inseminations during the breeding season (March-September), while the rest, 21 pregnancies resulted from conceptions in the non-breeding season (October to February). Pregnancies conceived in the breeding season were more likely (P < 0.01) to have at least 1 SCL (75.8 %, 135/178) than pregnancies from the non-breeding season (33 %, 7/21). However, the pregnancy loss between Days 35 and 120 of pregnancy in mares with no SCL was similar (3.5 %, 2/57; P >0.1) than from mares with SCL (1.4 %, 2/142). In Experiment 2 (Southern Hemisphere), three groups of recipients were used based on their ovarian activity at the time of embryo transfer: Anestrus (n = 8), transitional (n = 7) and cyclic (n = 7) recipient mares. While all transitional and cyclic mares developed at least 1 SCL, only 50 % of anestrous recipients (4/8) developed SCL by 120 of gestation. In conclusion, the development of SCL in pregnant mares is influenced by the time of season of conception, therefore it appears to be regulated by the photoperiod and the endogenous seasonal variation in gonadotropin concentrations. Mares with no SCL were not at increased risk of pregnancy loss.
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Anestro , Corpo Lúteo , Gravidez , Feminino , Animais , Estações do Ano , BrasilRESUMO
Before the colonial period, California harboured more language variation than all of Europe, and linguistic and archaeological analyses have led to many hypotheses to explain this diversity1. We report genome-wide data from 79 ancient individuals from California and 40 ancient individuals from Northern Mexico dating to 7,400-200 years before present (BP). Our analyses document long-term genetic continuity between people living on the Northern Channel Islands of California and the adjacent Santa Barbara mainland coast from 7,400 years BP to modern Chumash groups represented by individuals who lived around 200 years BP. The distinctive genetic lineages that characterize present-day and ancient people from Northwest Mexico increased in frequency in Southern and Central California by 5,200 years BP, providing evidence for northward migrations that are candidates for spreading Uto-Aztecan languages before the dispersal of maize agriculture from Mexico2-4. Individuals from Baja California share more alleles with the earliest individual from Central California in the dataset than with later individuals from Central California, potentially reflecting an earlier linguistic substrate, whose impact on local ancestry was diluted by later migrations from inland regions1,5. After 1,600 years BP, ancient individuals from the Channel Islands lived in communities with effective sizes similar to those in pre-agricultural Caribbean and Patagonia, and smaller than those on the California mainland and in sampled regions of Mexico.