Volunteer Subjects Research Articles

Time and environmental conditions for heat stress recovery based on human physiological responses: Developing a predictive model

Breaks can protect workers exposed to high temperatures from heat stress and other health risks. However, the most suitable recovery conditions and how the body physiologically responds to them remain uncertain. The aim of this study was to provide scientific evidence of the human physiological response to step changes in environmental parameters of recovery stage through climate chamber experiments and to develop a predictive model. Volunteer subjects experienced 60 min of walking exercise in air temperatures of 32 and 36 °C, RH 60%, and an air velocity of 0.2 m/s to form two heat stress levels, and then moved into a resting space under designated environmental conditions, such as a standard effective temperature (SET) range of 15.6–26.0 °C. The results showed that the recovery time for physiological parameters decreased with decreasing SET, accompanied by a simultaneous increase in thermal discomfort rate. Correlation analysis suggested that recovery time was related to the physiological stress index at the beginning of the recovery phase (PSI0; r = 0.86) and the SET (r = 0.75) of the recovery environment. A predictive model of heat stress recovery time was developed based on PSI0 and SET, with a determination coefficient of 0.9. According to the model, a SET of 18.8–24.9 °C was suitable for people with high heat stress requiring full recovery in 15–30 min. The research findings contribute to the regulation of health and safety in high-temperature working environments and the operation of restroom environmental conditions.

Associations between Circulating Biomarkers of One-Carbon Metabolism and Mitochondrial D-Loop Region Methylation Levels.

One-carbon metabolism is a critical pathway for epigenetic mechanisms. Circulating biomarkers of one-carbon metabolism have been associated with changes in nuclear DNA methylation levels in individuals affected by age-related diseases. More and more studies are showing that even mitochondrial DNA (mtDNA) could be methylated. In particular, methylation of the mitochondrial displacement (D-loop) region modulates the gene expression and replication of mtDNA and, when altered, can contribute to the development of human illnesses. However, no study until now has demonstrated an association between circulating biomarkers of one-carbon metabolism and D-loop methylation levels. In the study presented herein, we searched for associations between circulating one-carbon metabolism biomarkers, including folate, homocysteine, and vitamin B12, and the methylation levels of the D-loop region in DNA obtained from the peripheral blood of 94 elderly voluntary subjects. We observed a positive correlation between D-loop methylation and vitamin B12 (r = 0.21; p = 0.03), while no significant correlation was observed with folate (r = 0.02; p = 0.80) or homocysteine levels (r = 0.02; p = 0.82). Moreover, D-loop methylation was increased in individuals with high vitamin B12 levels compared to those with normal vitamin B12 levels (p = 0.04). This is the first study suggesting an association between vitamin B12 circulating levels and mtDNA methylation in human subjects. Given the potential implications of altered one-carbon metabolism and mitochondrial epigenetics in human diseases, a deeper understanding of their interaction could inspire novel interventions with beneficial effects for human health.

Wipe Disinfection of Reusable Elastomeric Half-Mask Respirators for Health Care Use.

During shortages, elastomeric half-mask respirators (EHMRs) are an alternative to reusing N95 filtering facepiece respirators but require between-use disinfection. The objectives of this study were to (a) measure microbial reductions on EHMR surfaces under laboratory conditions by a standardized procedure using wipes impregnated with health care disinfectants and to (b) measure microbial reductions on EHMRs disinfected by volunteer health care providers. We inoculated EHMR (Honeywell model RU8500) surfaces with Pseudomonas aeruginosa, Bacillus atrophaeus spores, and bacteriophages MS2 and Φ6, and disinfected them using two wipes with hydrogen peroxide (HP), alcohols, and quaternary ammonium compounds (QACs). Then, we randomized 54 volunteer subjects into three groups (Group 1: two wipes with instructions, Group 2: five wipes with instructions, Group 3: no instructions or set number of wipes) and used 0.5% HP wipes without precleaning on EHMRs inoculated with Raoultella terrigena and MS2. The laboratory study demonstrated that all organisms achieved at least 4 log10 median reductions (HP>QAC/alcohol>QAC>QAC/saline). Pseudomonas was highly susceptible to HP and QAC/alcohol and Φ6 to all disinfectants. MS2 reduction was highest using HP and lowest using QAC/saline. Bacillus was least susceptible. The volunteer study showed a 3 to 4 log10 average reductions of bacteria and virus; Raoultella reductions were greater than MS2, with variability within and between subjects. Conclusions: HP disinfectant wipes used in laboratory and by volunteers reduce bacteria and viruses on EHMRs by 3 to 4 log10 on average. Commercially available hospital disinfectant wipes reduce bacteria and viruses on EHMRs and can fill the need for between-use disinfection. HP and combination QAC/alcohol have the greatest efficacy under our test conditions.

Correlation of deglutitive striated esophagus motor function and pharyngeal phase swallowing biomechanical events.

The functional relationship of striated esophagus (St.Eso) motor function with pharyngeal deglutitive biomechanical events has not been systematically studied. The aim of this study was to determine the spatio-temporal characteristics of St.Eso function and its correlation with pharyngeal biomechanics and bolus transport. We studied 50 healthy volunteer subjects (age range: 21-82 years, 31 female) by digital videofluoroscopy. All subjects were studied in a seated, upright position. Thirteen of these 50 volunteers also underwent high-resolution manometry (HRM) concurrent with fluoroscopy. We used laryngeal excursion as a surrogate for St.Eso excursion. Median duration of St.Eso excursion was 2.35 [1.93,2.85, 5th and 95th percentile] seconds. Mean maximum extent of St.Eso excursion was 2.84 ± 0.72 cm. We identified four distinct periods in deglutitive St.Eso motor function: P1. Anterosuperior ascent without bolus or peristaltic activity, P2. Non-peristaltic bolus receiving at the apogee of St.Eso excursion concurrent with UES opening and pharyngeal peristalsis P3. Peristaltic bolus transport as St.Eso descends and P4. Continued peristalsis in resting position. 1. St.Eso motor function spans both pharyngeal and esophageal phases of swallowing for receiving and transporting the bolus, 2. Pressure signatures in HRM recordings currently attributed to St.Eso deglutitive motor activity does not represent the entirety of St.Eso peristalsis, only the part that occurs in its resting position. St.Eso peristalsis that occurs during its descent is recorded by pressure sensors initially in the pharynx. This finding needs to be considered when interpreting HRM recordings of the pharynx and proximal esophagus.

Feasibility Study on the Use of Infrared Cameras for Skin Cancer Detection under a Proposed Data Degradation Model.

Infrared thermography is considered a useful technique for diagnosing several skin pathologies but it has not been widely adopted mainly due to its high cost. Here, we investigate the feasibility of using low-cost infrared cameras with microbolometer technology for detecting skin cancer. For this purpose, we collected infrared data from volunteer subjects using a high-cost/high-quality infrared camera. We propose a degradation model to assess the use of lower-cost imagers in such a task. The degradation model was validated by mimicking video acquisition with the low-cost cameras, using data originally captured with a medium-cost camera. The outcome of the proposed model was then compared with the infrared video obtained with actual cameras, achieving an average Pearson correlation coefficient of more than 0.9271. Therefore, the model successfully transfers the behavior of cameras with poorer characteristics to videos acquired with higher-quality cameras. Using the proposed model, we simulated the acquisition of patient data with three different lower-cost cameras, namely, Xenics Gobi-640, Opgal Therm-App, and Seek Thermal CompactPRO. The degraded data were used to evaluate the performance of a skin cancer detection algorithm. The Xenics and Opgal cameras achieved accuracies of 84.33% and 84.20%, respectively, and sensitivities of 83.03% and 83.23%, respectively. These values closely matched those from the non-degraded data, indicating that employing these lower-cost cameras is appropriate for skin cancer detection. The Seek camera achieved an accuracy of 82.13% and a sensitivity of 79.77%. Based on these results, we conclude that this camera is appropriate for less critical applications.

Features of social identity of volunteers engaged in professionally oriented volunteer activities and subject to emotional burnout

Features of social identity of volunteers engaged in professionally oriented volunteer activities and subject to emotional burnout

Human Activity Recording Based on Skin-Strain-Actuated Microfluidic Pumping in Asymmetrically Designed Micro-Channels.

The capability to record data in passive, image-based wearable sensors can simplify data readouts and eliminate the requirement for the integration of electronic components on the skin. Here, we developed a skin-strain-actuated microfluidic pump (SAMP) that utilizes asymmetric aspect ratio channels for the recording of human activity in the fluidic domain. An analytical model describing the SAMP's operation mechanism as a wearable microfluidic device was established. Fabrication of the SAMP was achieved using soft lithography from polydimethylsiloxane (PDMS). Benchtop experimental results and theoretical predictions were shown to be in good agreement. The SAMP was mounted on human skin and experiments conducted on volunteer subjects demonstrated the SAMP's capability to record human activity for hundreds of cycles in the fluidic domain through the observation of a stable liquid meniscus. Proof-of-concept experiments further revealed that the SAMP could quantify a single wrist activity repetition or distinguish between three different shoulder activities.

What do medical students think of own participation as subjects in clinical trials?

Testing of new drugs through clinical trials is essential in efforts to increase generalizable knowledge. Little is known about the medical students' perception of their participation as research subjects in clinical trials. The aim of this study was to examine the willingness and attitudes of medical students towards participation as volunteer subjects in clinical trials. A cross-sectional study was conducted among 297 medical students in years 4, 5 and 6 at the University of Belgrade, from October to December 2023. Participants completed a pen-and-paper questionnaire including demographic characteristics, opinions on their participation in clinical trials, and attitudes towards clinical trials in general. The validity of the attitude scale was verified. One in five medical students expressed a positive opinion about their participation in clinical trials, with the majority (about one-half)remaining undecided. General attitudes of students about research and their participation were positive. Students with prior blood donation experience were more willing to participate. Lower socioeconomic status and volunteering experience were also associated with stronger positive attitudes towards clinical trials in general. Most students were undecided about their participation, but their attitudes towards clinical trials in general were positive. Positive attitudes towards clinical trials did not uniformly translate to the willingness for personal participation. Promotion of blood donation and volunteering at universities could help to increase the interest in clinical trials as volunteer subjects.

Development and Psychometric Properties of the Spanish Social Stigma Scale (S3).

(1) Background: Mental health problems are associated with negative connotations that may lead to discrimination and rejection of people diagnosed with mental disorders. The present study aimed to develop and validate a new scale (the Spanish Social Stigma Scale-S3) to assess the current level of social stigma in the general Spanish population. (2) Methods: The assessment tool was developed after reviewing the items of existing tools that represent the most appropriate indicators for the assessment of social stigma. A review was performed by volunteer subjects and by a group of experts in the field, based on the participation of 563 respondents to a survey. (3) Results: The confirmatory factor analysis revealed that the developed tool fits with the factors that determine the level of social stigma and shows good internal consistency (χ2SB = 412.0321, gl = 293, p < 0.01; BBNNFI = 0.922; CFI = 0.930; IFI = 0.931; RMSEA = 0.028 [0.022, 0.035]). (4) Conclusions: The S3 is useful for assessing knowledge, attitudes, and behavior towards people diagnosed with a mental disorder. This tool may be used for the identification and development of mechanisms necessary for the reduction of social stigma in the general population.

Serological Evidence of Epstein-Barr Virus Capsid Antigen (EB-CA) Among Pregnant Women from Cottage Hospital, Ilorin

Study’s Excerpt/Novelty This study reveals a significant Epstein-Barr Virus (EBV) prevalence among pregnant women attending Cottage Hospital in Ilorin, with 95.69% of participants testing positive for anti-EBV IgG antibodies. Notably, the highest prevalence was observed among younger women, those in the first trimester, individuals from polygamous families, and those with lower educational levels. These findings underscore the need for increased community awareness and improved personal hygiene practices to reduce EBV infection rates and associated congenital defects. Full Abstract Epstein-Barr Virus (EBV), a member of the Herpesvirus family, has been observed to be increasing among pregnant women, leading to congenital defects. This study aimed to determine the prevalence of EBV infection among pregnant women attending Cottage Hospital in Ilorin. A total of 45 pregnant women were tested, and questionnaires were administered to volunteer subjects after obtaining their informed consent. Approximately 5 ml of blood was aseptically collected via venous puncture from the antecubital fossa and dispensed into EDTA containers. Plasma was separated after centrifugation of the blood, and the obtained plasma was screened for anti-EBV IgG antibodies using ELISA techniques. Results revealed that 43 subjects (95.69%) tested positive for EBV, while 2 (4.4%) tested negative. Among different age groups, women aged 19-20, 26-30, and 36-40 showed a prevalence rate of 100%, with the lowest prevalence of 88.8% recorded among the 31-35 age group. Regarding the pregnancy stage, 100% was seen among first-trimester participants, while the lowest prevalence of 92.3% was noted during the third trimester. The majority of respondents were married, with those from polygamous families and single individuals showing a prevalence of 100%. Participants with primary and secondary education levels displayed the highest prevalence, while those with tertiary education had the lowest. Muslims had the highest prevalence, whereas Christians had the lowest. Moreover, regarding occupation, the unemployed, artisans, and students had the highest prevalence, while civil servants and businesswomen had the lowest prevalence. In conclusion, the results from this study highlight a notable prevalence of EBV (IgG) antibodies among pregnant women. These outcomes emphasize the necessity of raising awareness in the community about the implications of EBV infection and the Significance of maintaining proper personal hygiene to mitigate the chances of infection and spread

Barefoot pressure distribution of diabetic patients and non-diabetic volunteer subjects after sensorimotor training with an unstable shoe construction

BackgroundForty-three percent of all diabetic foot ulcers occur under the medial forefoot due to a medial deviation of elevated pressures and premature forefoot ground contact in neuropathic diabetic patients. A 6-week sensorimotor training period with an unstable shoe construction reduces in-shoe peak pressures and contact times under the medial aspect of the forefoot. MethodsThe study was designed as a Randomised Control Trial with two diabetic groups (one served as intervention group and one as control group) and one non-diabetic intervention group. Measurements for barefoot pressure distribution and contact times were taken by means of an Emed® pressure measurement platform (Novel GmbH, Munich) before and after 6 weeks. During this time the diabetic and the non-diabetic intervention groups were required to wear an unstable shoe construction (Masai Barefoot Technology, MBT®) for at least four hours per day. FindingsResults for the non-diabetic intervention group showed significantly later contact times for the medial portion of the forefoot, resulting in shorter contact times. Peak pressure was also reduced under the medial aspect of the foot while it was increased under the lateral aspect of the foot. Changes for the diabetic intervention group followed the same pattern while the values of the diabetic control group shifted away from the reference values. InterpretationA 6-week sensorimotor training period with an unstable shoe construction can change barefoot peak pressures and contact times in non-diabetic subjects and in diabetic patients in the most endangered area, i.e. the medial forefoot.

Estimation of Sex From the Buccolingual Dimension of Tooth Among the North Indian Population.

Identification is an important aspect of forensic medicine. Identification plays an imperative role, especially in highly decomposed bodies, mutilated bodies, and undisclosed and fragmentary human remains. The estimation of sex is an essential parameter of human identification. In forensic anthropometry, sex determination is related to morphometric characteristics of skeletal bones, such as the skull and mandible, clavicle, sternum, scapula, humerus, pelvic bone, sternum, and femur. Since teeth are decay-resistant, conscientious analysis of teeth can accredit reliable sex estimation of an individual, especially when other determinants are fragmented or destroyed. The aim of the study was to explore the association between sex and buccolingual crown dimensions of teeth. The study sample consists of 100 volunteer subjects (50 male subjects and 50 female subjects) aged between 20 and 35 years. Alginate was used to take impressions of the teeth and the cast was prepared using pouring by dental stone. Measurements of buccolingual parameters of all the teeth (except the third molars) of both jaws were done on dental casts by using a digital caliper. Collected data were analyzed using SPSS software (IBM Corp., Armonk, NY) and were outlined as mean and standard deviation (SD). The male and female groups were compared using an independent Student's t-test or unpaired test. The results of this study revealed that 16 out of 28 odontometric parameters (except third molar) of the two groups (male and female) were higher in the male group as compared to the female group (p < 0.05). Buccolingual odontometric parameters can be used for sex estimation in the North Indian population.

Cell immunity to SARS-CoV-2 after natural infection and/or different vaccination regimens.

The aim of the study was to evaluate the humoral and cellular immunity after SARS-CoV-2 infection and/or vaccination according to the type of vaccine, number of doses and combination of vaccines. Volunteer subjects were sampled between September 2021 and July 2022 in Hospital Clínico San Carlos, Madrid (Spain). Participants had different immunological status against SARS-CoV-2: vaccinated and unvaccinated, with or without previous COVID-19 infection, including healthy and immunocompromised individuals. Determination of IgG against the spike protein S1 subunit receptor-binding domain (RBD) was performed by chemiluminescence microparticle immunoassay (CMIA) using the Architect i10000sr platform (Abbott). The SARS-CoV-2-specific T-cell responses were assessed by quantification of interferon gamma release using QuantiFERON SARS-CoV-2 assay (Qiagen). A total of 181 samples were collected, 170 were from vaccinated individuals and 11 from unvaccinated. Among the participants, 41 were aware of having previously been infected by SARS-CoV-2. Vaccinated people received one or two doses of the following vaccines against SARS-CoV-2: ChAdOx1-S (University of Oxford-AstraZeneca) (AZ) and/orBNT162b2 (Pfizer-BioNTech)(PZ). Subjects immunized with a third-booster dose received PZ or mRNA-1273 (Moderna-NIAID)(MD) vaccines. All vaccinees developed a positive humoral response (>7.1 BAU/ml), but the cellular response varied depending on the vaccination regimen. Only AZ/PZ combination and 3 doses of vaccination elicited a positive cellular response (median concentration of IFN- γ > 0.3 IU/ml). Regarding a two-dose vaccination regimen, AZ/PZ combination induced the highest humoral and cellular immunity. A booster with mRNA vaccine resulted in increases in median levels of IgG-Spike antibodies and IFN-γ as compared to those of two-dose of any vaccine. Humoral and cellular immunity levels were significantly higher in participants with previous infection compared to those without infection. Heterologous vaccination (AZ/PZ) elicited the strongest immunity among the two-dose vaccination regimens. The immunity offered by the third-booster dose of SARS-CoV-2 vaccine depends not only on the type of vaccine administered but also on previous doses and prior infection. Previous exposure to SARS-CoV-2 antigens by infection strongly affect immunity of vaccinated individuals.

Longitudinal Changes in the Body Mass Index of British Army Pilots.

INTRODUCTION: Aircraft are manufactured according to design parameters that must account for the size and physical characteristics of the pilot. While cockpit dimensions, seats, restraints, and related components do not change substantially over the airframe lifecycle, it is conceivable that the occupant may, even if initially well-suited. This investigation focused on longitudinal body mass index (BMI) changes within a cohort of British Army Air Corps pilots.METHODS: The study was a retrospective examination of electronic medical record data to assess longitudinal change within a representative cohort of Army pilots. Voluntary subjects were assigned unique subject numbers matched with individual electronic medical record data. Subject's age, service length, height, weight, and BMI were extracted from routine historical aviation medical exams.RESULTS: Among 106 British Army Air Corps pilots, the mean age was 35.3 yr (SD = 7.4) with average length of service as a pilot of 9.0 yr (SD = 5.2). Within the observed cohort, the mean change in individual weight over time was an increase of 4.6 kg (SD = 7.3). Height remained relatively stable with a mean increase of 0.6 cm (SD = 1.9). Given the increase in weight, BMI was noted to increase longitudinally with a mean of 1.3 kg · m-2 (SD = 2.4).DISCUSSION: British Army pilots experience increases in BMI over time much like the general population. Results of this study serve to inform future policy related to the body composition of aviation applicants, the retention of previously qualified pilots, and the safety concerns of crashworthiness design specifications.Porter WD, Wilde GD, Jeffery NP, Walters PL, Eke AJ, Bushby AJR, Adams MS, Gaydos SJ. Longitudinal changes in the body mass index of British Army pilots. Aerosp Med Hum Perform. 2024; 95(2):118-122.

Blood Flow Restriction Exercises (BFR) an Effect on Strength Rehabilitation and Muscle Atrophy for Patients with Multiple Femur Fractures Aged 40-50 Years

The present study examined the effect of rehabilitation exercises with BFR in improving muscle strength, thigh muscle hypertrophy, and knee joint flexibility for those with double fractures in the lower body. Methods: 6 volunteer subjects (average age 44 (40–50) years) were randomized into one group that trained in restriction of blood flow period eight weeks. Participants were familiar with all testing and exercise protocols before starting the study. Rehabilitation exercises with BFR were done before and after—form for each player to record the sequence measurements. Quadriceps circumference measurement (cm), the range of motion of the knee joint, and Quadriceps muscle strength measurement were performed on the participants. Independent samples t-test was used to compare the scores obtained from the measurements according to categorical variables. The significance level was determined as P 0.05. Results: Thigh circumference (cm) There was a significant increase in thigh circumference from before the experiment (41.17 cm) to after the investigation (45.33 cm) (p&amp;lt;0,001). There's a remarkable development in post-test measurements (13.97 kg), (p&amp;lt;0,000) compared to pre-test measurements (8.83 kg), indicating an improvement in quadriceps strength. Hamstring strength (kg) in the post-test measurement (10.17 kg) demonstrated a remarkable development compared to the pre-test measurement (7.5 kg) (p&amp;lt;0,003). The post-test measurement (24.5 degrees) showed significant development compared to the pre-test measurement (60.83 degrees) (p&amp;lt;0,000), suggesting an improvement in the range of motion of the flexed knee joint. In conclusion, it shows that blood flow restriction is a safe and effective treatment for people with multiple fractures.

Racial effects on masimo pulse oximetry: impact of low perfusion index

Purpose: Evaluate the SpO2-SaO2 difference between Black and White volunteer subjects having a low perfusion index (Pi) compared to those having a normal Pi. Methods: The Pi data were abstracted from electronic files collected on 7183 paired SpO2-SaO2 samples (3201 Black and 3982 White) from a recently reported desaturation study of 75 subjects (39 Black and 36 White) where SaO2 values were sequentially decreased from 100 to 70%. The Pi values from that dataset were divided into two groups (Pi ≤ 1 or Pi > 1) for analysis. A Pi value ≤ 1 was considered “low perfusion” and a Pi value > 1 was considered “normal perfusion”. Statistical calculations included values of bias (mean difference of SpO2-SaO2), precision (standard deviation of the difference), and accuracy (root-mean-square error [ARMS]). During conditions of low perfusion (Pi ≤ 1, range [0.1 to 1]), overall bias and precision were + 0.48% ± 1.59%, while bias and precision were + 0.19 ± 1.53%, and + 0.91 ± 1.57%, for Black and White subjects, respectively. Results: During normal perfusion (Pi > 1, range [1 to 12]), overall bias and precision were + 0.18% ± 1.34%, while bias and precision were -0.26 ± 1.37%, and − 0.12 ± 1.31%, for Black and White subjects, respectively. ARMS was 1.37% in all subjects with normal perfusion and 1.64% in all subjects with low perfusion. Conclusion: Masimo SET® pulse oximeters with RD SET® sensors are accurate for individuals of both Black and White races when Pi is normal, as well as during conditions when Pi is low. The ARMS for all conditions studied is well within FDA standards. This study was conducted in healthy volunteers during well-controlled laboratory desaturations, and results could vary under certain challenging clinical conditions.

Myotonometric Assessment of the Short-Term Effects of Manual Therapy on Upper Trapezius Myofascial Trigger Points

(1) Background: The aim of this study was to assess the short-term effects of one manual therapeutic intervention by quantifying the biomechanical and viscoelastic properties of upper trapezius myofascial trigger points. (2) Materials and Methods: Fourteen volunteer subjects (six males and eight females) aged 22 to 47 years, with myofascial trigger points in the upper trapezius muscle on both sides participated in this study. The biomechanical and viscoelastic properties were assessed with the Myoton Pro (Estonia) before the application of manual therapy (T0), then immediately after the end of the treatment session (T1) and finally one hour after the end of the treatment session (T2) in order to evaluate the effectiveness of the applied treatment. (3) Results: The oscillation frequency in the right upper trapezius muscle was significantly lower than in the left upper trapezius muscle both immediately, after the end of the manual therapy session (p = 0.03) and one hour after the session (p = 0.03). Regarding the state of tension in the right upper trapezius, a significant decrease was observed one hour after treatment compared to baseline (p = 0.04). In the left upper trapezius muscle, one hour after treatment, the dynamic stiffness value was significantly higher than in the right upper trapezius (p = 0.01). (4) Conclusions: Myotonometry could become a useful method to assess the biomechanical and viscoelastic properties of muscles, identifying trigger points and monitoring the results of therapy.

Different physicochemical interactions between varietal wines and human saliva: Correspondence with astringency

Astringency corresponds to the sensation of dryness and roughness that is experienced in the oral cavity in association with the interaction between salivary proteins and food polyphenols. In this study, the phenolic composition of seven varietal wines, the intensity of astringency they evoke and the physicochemical reactivity of these wines with whole human saliva were evaluated.Phenolic composition of wines was characterized by spectrophotometry and HPLC chromatography. Intensity of astringency was evaluated by trained sensory panels. Saliva from a single volunteer subject was used to assess wine-saliva interactions. To this end, binary mixtures were produced at different v/v wine/saliva ratios and each of them assayed for the ability of the salivary protein to diffuse on a cellulose membrane (diffusion test) and to remain in solution (precipitation test). Physicochemical reactivities between wine components and the protein fraction of saliva were contrasted against the astringency and the phenolic profile of each varietal wine. The study supports the view that astringency depends on physicochemical interactions between two complex matrices -wine and saliva- and not between some of their particular components.

Intra-abdominal Content Movement in Prone Versus Lateral Decubitus Position Lateral Lumbar Interbody Fusion (LLIF).

A prospective, anatomical imaging study of healthy volunteer subjects in accurate surgical positions. To establish if there is a change in the position of the abdominal contents in the lateral decubitus (LD) versus prone position. Lateral transpsoas lumbar interbody fusion (LLIF) in the LD position has been validated anatomically and for procedural safety, specifically in relation to visceral risks. Recently, LLIF with the patient in the prone position has been suggested as an alternative to LLIF in the LD position. Subjects underwent magnetic resonance imaging of the lumbosacral region in the right LD position with the hips flexed and the prone position with the legs extended. Anatomical measurements were performed on axial magnetic resonance images at the L4-5 disc space. Thirty-four subjects were included. The distance from the skin to the lateral disc surface was 134.9mm in prone compared with 118.7mm in LD ( P <0.0001). The distance between the posterior aspect of the disc and the colon was 20.3mm in the prone compared with 41.1mm in LD ( P <0.0001). The colon migrated more posteriorly in relation to the anterior margin of the psoas in the prone compared with LD (21.7 vs . 5.5mm, respectively; P <0.0001). 100% of subjects had posterior migration of the colon in the prone compared with the LD position, as measured by the distance from the quadratum lumborum to the colon (44.4 vs . 20.5mm, respectively; P <0.001). There were profound changes in the position of visceral structures between the prone and LD patient positions in relation to the LLIF approach corridor. Compared with LD LLIF, the prone position results in a longer surgical corridor with a substantially smaller working window free of the colon, as evidenced by the significant and uniform posterior migration of the colon. Surgeons should be aware of the potential for increased visceral risks when performing LLIF in the prone position. Level II-prospective anatomical cohort study.

Isometric handgrip exercise training as a potential tool for identifying and regulating blood pressure in young healthy adults

Background: Isometric handgrip (IHG) exercises can be a simple tool and an effective, time-consumable test that may be beneficial for blood pressure (BP) regulation. Hypertension prevention or BP control is necessary nowadays. Isometric exercise evokes the contractions of skeletal muscle without altering their length, but changes in the tension of the muscle occur. Through lifestyle modification, static exercises maintain the desired BP in individuals other than aerobic exercises. Aims and Objectives: The aim of the study was to evaluate the effective changes of isometric handgrip exercise on young, healthy subjects and determine changes in heart rate (HR) and BP before and after exercise. Materials and Methods: A randomized controlled study has been conducted in the department of physiology at JMC Rajasthan for 3 months. The study sample included 72 volunteer subjects (40 male and 32 females) aged 19–25 years, and handgrip spring dynamometers are used for IHE exercise training. The IHE training group performed handgrip exercises for 3 months at 30% of their maximum isometric contraction, 3 times/week for five 3-min bouts with 5-min rest periods between each bout. Before and after the intervention, BP and HR were measured. The P-value was advised significantly at 0.05. Results: At the completion of 3 months of IHE exercise training, significant changes are seen in HR and BP in all healthy volunteers (P &lt; 0.001 for all forms of BP) (HR, P = 0.014). In female volunteer and diastolic BP, it decreases significantly, but no significant changes are seen in systolic BP, mean arterial pressure, and HR. Conclusion: IHG exercise training reduces or regulates baseline BP and HR and explores the potential of this intervention for managing or preventing hypertension.