Size In Individuals Research Articles

HIV Subtype and Nef-Mediated Immune Evasion Function Correlate with Viral Reservoir Size in Early-Treated Individuals.

The HIV accessory protein Nef modulates key immune evasion and pathogenic functions, and its encoding gene region exhibits high sequence diversity. Given the recent identification of early HIV-specific adaptive immune responses as novel correlates of HIV reservoir size, we hypothesized that viral factors that facilitate the evasion of such responses-namely, Nef genetic and functional diversity-might also influence reservoir establishment and/or persistence. We isolated baseline plasma HIV RNA-derived nef clones from 30 acute/early-infected individuals who participated in a clinical trial of early combination antiretroviral therapy (cART) (<6 months following infection) and assessed each Nef clone's ability to downregulate CD4 and human leukocyte antigen (HLA) class I in vitro We then explored the relationships between baseline clinical, immunological, and virological characteristics and the HIV reservoir size measured 48 weeks following initiation of suppressive cART (where the reservoir size was quantified in terms of the proviral DNA loads as well as the levels of replication-competent HIV in CD4+ T cells). Maximal within-host Nef-mediated downregulation of HLA, but not CD4, correlated positively with post-cART proviral DNA levels (Spearman's R = 0.61, P = 0.0004) and replication-competent reservoir sizes (Spearman's R = 0.36, P = 0.056) in univariable analyses. Furthermore, the Nef-mediated HLA downregulation function was retained in final multivariable models adjusting for established clinical and immunological correlates of reservoir size. Finally, HIV subtype B-infected persons (n = 25) harbored significantly larger viral reservoirs than non-subtype B-infected persons (2 infected with subtype CRF01_AE and 3 infected with subtype G). Our results highlight a potentially important role of viral factors-in particular, HIV subtype and accessory protein function-in modulating viral reservoir establishment and persistence.IMPORTANCE While combination antiretroviral therapies (cART) have transformed HIV infection into a chronic manageable condition, they do not act upon the latent HIV reservoir and are therefore not curative. As HIV cure or remission should be more readily achievable in individuals with smaller HIV reservoirs, achieving a deeper understanding of the clinical, immunological, and virological determinants of reservoir size is critical to eradication efforts. We performed a post hoc analysis of 30 participants of a clinical trial of early cART who had previously been assessed in detail for their clinical, immunological, and reservoir size characteristics. We observed that the HIV subtype and autologous Nef-mediated HLA downregulation function correlated with the viral reservoir size measured approximately 1 year post-cART initiation. Our findings highlight virological characteristics-both genetic and functional-as possible novel determinants of HIV reservoir establishment and persistence.

Lonely But Not Alone: Neuroticism Mediates the Relationship Between Social Network Size and Loneliness in Individuals With Traumatic Brain Injury.

Objectives: Although individuals with traumatic brain injury (TBI) often report higher levels of social isolation, little is known about the factors influencing their self-perception of loneliness. The aim of the current study was to investigate the relationship between loneliness, social network size, and personality variables (neuroticism and extraversion) after TBI, and in particular whether specific personality variables mediate the relationship between social network size and perception of loneliness. Methods: Here, we assessed self-reported loneliness, personality variables, and social network size of 24 individuals with moderate-to-severe TBI and 41 healthy comparison participants. We then carried out a mediation analysis to examine whether personality variables mediated the relationship between loneliness and social network size. Results: Our results indicate that individuals with TBI reported higher levels of loneliness and neuroticism, but there was no group difference in social network size or extraversion. The mediation analysis revealed that the association between social network size and loneliness was mediated by neuroticism, but not by extraversion. Conclusions: Our findings show that neuroticism is an intervening variable in the relationship between social network size and self-perception of loneliness in individuals with moderate-to-severe TBI, and presents a new possible target for clinicians and rehabilitators seeking to address reports of loneliness and social isolation in TBI. (JINS 2019, 25, 266-274).

An updated normative data set from the autonomic reflex screen representative of Southwestern Ontario.

In evaluating autonomic dysfunction, the autonomic reflex screen (ARS) is an established set of standardized tests to evaluate the presence and severity of autonomic dysfunction. Our laboratory previously reported normative data on 121 healthy individuals; however, the sample size in older individuals was reduced compared with other age groups. Therefore, the objective of the current study was to provide updated normative values representative of young, middle-aged, and older individuals from Southwestern Ontario. Two hundred and fifty-two healthy individuals completed quantitative sudomotor axon reflex testing, heart rate responses to deep breathing (HRDB), and Valsalva maneuver using standard protocols of the ARS. All 4 sweat sites demonstrated a significant effect of sex (p < 0.001). In addition, the proximal leg, distal leg, and foot were all significantly affected by age (p < 0.001). Cardiovagal parameters, measured via HRDB and Valsalva ratio revealed a significant regression with age (p < 0.001). These results show similar trends with previously reported normative data sets. All normative data as a function of age and sex, where appropriate, are expressed as percentiles (2.5th, 5th, 95th, 97.5th). The current study provides updated normative data describing autonomic functioning in healthy individuals obtained from the sudomotor and cardiovagal components of the ARS.

Effects of 10-week walking and walking with home-based resistance training on muscle quality, muscle size, and physical functional tests in healthy older individuals

BackgroundOlder individuals have been shown to present muscle atrophy in conjunction with increased fat fraction in some muscles. The proportion of fat and connective tissue within the skeletal muscle can be estimated from axial B-mode ultrasound images using echo intensity (EI). EI was used to calculate the index of muscle quality. Walking, home-based weight-bearing resistance training, and its combinations are considered simple, easy, and practical exercise interventions for older adults. The purpose of this study was to quantify the effects of walking and walking with home-based resistance training on muscle quality of older individuals.MethodsThirty-one participants performed walking training only (W-group; 72 ± 5 years) and 33 participants performed walking and home-based resistance training (WR-group; 73 ± 6 years). This study was a non-randomized controlled trial with no control group. All participants were instructed to walk 2 or 3 sets per week for 10 weeks (one set: 30-min continuous walking). In addition, the WR-group performed home-based weight-bearing resistance training. EI was measured as a muscle quality index using axial B-mode ultrasound images of the rectus femoris and vastus lateralis of the mid-thigh. We further averaged these parameters to obtain the EI of the quadriceps femoris (QF). Participants further performed five functional tests: sit-ups, supine up, sit-to-stand, 5-m maximal walk, and 6-min walk.ResultsQF EI was significantly decreased in both groups after training (W-group 69.9 ± 7.4 a.u. to 61.7 ± 7.0 a.u., WR-group 64.0 ± 9.5 a.u. to 51.1 ± 10.0 a.u.; P < 0.05), suggesting improved muscle quality. QF EI was further decreased in the WR-group compared with the W-group. The sit-up test in both groups and the sit-to-stand and 5-m maximal walk tests in the W-group were significantly improved after training.ConclusionThese results suggest that training-induced stimulation is associated with a decrease in EI in some thigh regions. Furthermore, the addition of home-based resistance training to walking would be effective for a greater reduction of EI.

Effect of simulated microgravity on the circadian rhythm of Drosophila melanogaster

Biological interactions and environmental constraints alter life-history traits, modifying organismal performances. Trematode parasites often impact their hosts by inducing parasitic castration, frequently correlated with increased body size in the host (i.e., gigantism hypothesis), which is postulated to reflect the re-allocation of energy released by the reduction in the reproductive process. In this study, we compared the effect of a trematode species on shell size and morphology in adult individuals of the intertidal mussels Perumytilus purpuratus (>20 mm) collected from two local populations of contrasting environmental regimes experienced in central-southern Chile. Our field data indicates that in both study locations, parasitized mussels evidenced higher body sizes (shell length, total weight and volume) as compared with non-parasitized. In addition, parasitized mussels from the southern location evidenced thinner shells than non-parasitized ones and those collected from central Chile, suggesting geographical variation in shell carbonate precipitation across intertidal habitats of the Chilean coast. In laboratory conditions, mussels collected from a local population in central Chile were exposed to two temperature treatments (12 and 18 °C). Parasitized mussels showed higher growth rates than non-parasitized, regardless of the seawater temperature treatments. However, the metabolic rate was not influenced by the parasite condition or the temperature treatments. Our field and laboratory results support the parasite-induced gigantism hypothesis, and suggest that both the thermal environment and geographic location explain only a portion of the increased body size, while the parasitic condition is the most plausible factor modulating the outcome of this host-parasite interaction.

Sexual signals reveal males’ oxidative stress defences: Testing this hypothesis in an invertebrate

Abstract The hypothesis that sexual traits reveal the oxidative stress resistance of their bearers has been widely tested in vertebrates but remains unexplored in invertebrates. Here, Hetaerina americana was used to test whether oxidative stress defences are advertised by male wing spot size and colour (a male sexual trait). To this end, we investigated (1) whether oxidative stress reduced survival, (2) whether wing spot size revealed males’ antioxidant defences and (3) how wing spot size and colour were affected by oxidative stress. We elevated oxidative stress by injecting adult males with paraquat (PQ, a compound that favours the production of free radicals) and then examined how this affected male survival and wing spot size. We then related the expression of wing spot size to indicators of oxidative stress—hydrogen peroxide (H2O2) and total antioxidant capacity (TAC), super oxide dismutase (SOD) and catalase (CAT)—in adult males (whose wing spot is fixed) injected with PQ. In teneral males, whose wing spots are still forming, we compared wing spot size, colour (red and yellow chroma) and brightness in individuals injected with PQ or water as a control. Oxidative stress reduced the survival of adult and teneral males. While the H2O2 and TAC markers of antioxidant defences were positively correlated with wing spot size, there was no correlation with CAT and a negative correlation with SOD. In teneral males, PQ increased the yellow chroma and brightness of wing spots, but did not affect spot size or red chroma. Our results highlight the importance of measuring different markers as indicators of male oxidative stress defences, and that the sexual signals of invertebrates may reveal the oxidative stress status of their bearers. A plain language summary is available for this article.

Abstract P3-05-17: The numbers of Foxp3 positive cells in simultaneous bilateral breast cancer

Abstract Background Evasion of the immune system is one of the hallmarks of malignant tumors, and recently blocking of such evasion has been used in clinical practice for the treatment of some types of cancers. Recruitment of regulatory T cells (Tregs), which express the specific marker Foxp3, is an established mechanism of escaping from the immune system. In breast cancer, it has been reported that the number of Tregs differs widely among breast cancer subtypes, and that patients who have many Tregs around the tumor tend to have a poor prognosis. However, the factors that are important for the recruitment of Tregs are not well known. Thus, factors that depend on the host (e.g., age or comorbidity), on the tumor (e.g., subtype, grade, or stage), or on measurement error might be the cause of the observed differences in the number of Tregs. In this study, we investigated the numbers of Tregs in simultaneous bilateral breast cancer patients in order to determine the factors that influence the recruitment of Tregs, while excluding differences in individuals as much as possible. Material and methods Patients who had breast cancer in both breasts and who underwent simultaneous surgery between January 2005 and September 2015 at two institutions were enrolled in this study. Patients who underwent primary systemic therapy who were diagnosed with ductal carcinoma in situ, or who were stage IV were excluded. The average numbers of Foxp3-positive (Foxp3+cells) were determined from scores of five high-power fields (HPFs). The association between the difference in Foxp3+ cell number between each breast in a single individual and clinicopathological features was examined. Results Seventy patients were included in this study. Their ages ranged from 39-85 (median 54) years old. Ninety five percent of the tumors were invasive ductal carcinoma non-special type. Eighty eight (62.9%), 43 (30.7%), and 9 (6.4%) of the tumors were T1, T2, and ≥T3, respectively, and 102 (72.9%) of the tumors were node-negative. Regarding nuclear grade (NG), 104 (74.3%), 21 (22.1%), and 7 (5%) of the tumors were NG1, 2, and 3, respectively. As for subtype, 124 (88.6%), 9 (6.4%), and 7 (5%) were ER-positive and HER2-negative(ER+/HER2-), ER-positive or negative and HER2-negative(ER±/HER2+), and ER-negative and HER2-negative(ER-/HER2-), respectively. The numbers of Foxp3+ cells ranged from 0 to 39.8 (median 3.3)/HPF, and difference in Foxp3+ cell number between each breast in a single individual ranged from 0 to 34 (median 3.9)/HPF. Differences in tumor size and node status in individuals did not impact on the number of Foxp3+ cells. However, the number of Foxp3+ cells in tumors that were NG3 (P=0.00098) or ER±/HER2+ or ER-/HER2- type (P=0.00586) were statistically significantly increased compared with tumors that were NG1/2 or ER+/HER2- type in the same host. Furthermore, the difference of Foxp3+ cells between each tumor in a single individual were quite small regarding tumor size and node status in 53 patients who had similar NG and subtype tumors in both breasts. Conclusions The number of Foxp3+ cells showed no relationship with tumor size, or lymph node status in simultaneous bilateral breast cancer patients. High NG, ER±/HER2+ or ER-/HER2- type of the tumor were involved with enhancement of the recruitment of Tregs. Citation Format: Goto R, Hirota Y, Aruga T, Horiguchi S, Tazawa S, Nakamura S, Takimoto M. The numbers of Foxp3 positive cells in simultaneous bilateral breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-05-17.

Predicted 10-year risk of cardiovascular mortality in the 40 to 69 year old general population without cardiovascular diseases in Germany.

AimsTo estimate the 10-year risk of fatal cardiovascular disease (CVD) in the 40 to 69 year old general population in Germany stratified by sex and to analyze differences between socio-economic status (SES), region and community size in individuals without CVD. The analysis is based on the newly recalibrated SCORE Deutschland risk charts and considered other comorbidities for the classification of the high CVD risk group according to the guidelines of the European Society of Cardiology.Methods and resultsIn 3,498 participants (40–69 years) from the German Health Examination Survey for Adults 2008–2011 (DEGS1) without a history of CVD (myocardial infarction, coronary heart disease, heart failure, stroke) we estimated the proportion with a low (SCORE <1%), moderate (SCORE 1-<5%) and high 10-year CVD mortality risk (SCORE ≥5% or diabetes, renal insufficiency, SBP/DPB ≥180/110 mmHg or cholesterol >8 mmol/l). The prevalence of low, moderate and high risk was 42.8%, 38.5% and 18.8% in men and 73.7%, 18.1% and 8.2% in women. The prevalence of high risk was significantly lower in women with a high compared to a low SES (3.3% vs. 11.2%) and in communities with ≥100.000 inhabitants compared to <20.000 inhabitants (5.4% vs.10.9%). There were no significant associations between predicted CVD mortality risk and SES or community size in men and regions in men and women. Among the high risk group, 58.2% of men and 9.8% of women had SCORE ≥5%, leaving the majority of women (60.1%) classified as high risks due to diabetes and SCORE <5%.ConclusionOur results suggest the persistence of socioeconomic disparities in predicted cardiovascular mortality in women and support the need of large-scale prevention efforts beyond individual lifestyle modification or treatment. Furthermore, the importance of additional comorbidities for the high risk group classification is highlighted.

Ultrasound measurement of liver longitudinal length in a North Anatolian population: A community-based study.

Liver size can be influenced by various factors, including malignant diseases, infective processes, and anthropometric variations among individuals from different geographical locations and races. Therefore, the exact definition of hepatomegaly in the ultrasonographic measurement of liver size is controversial. Moreover, the majority of studies regarding the study of liver size are not community-based. The aim of this study is to establish a range of normal liver sizes by ultrasonography with respect to age and sex in healthy individuals and to identify factors affecting liver size. This was a prospective, community-based study. Liver size was measured ultrasonographically from the midclavicular line in 822 individuals, of which 49.3% (n = 405) were male and 51.7% (n = 417) were female. Following physical examination, all participants provided blood samples. Height, weight, and waist circumference were recorded. The mean liver length was calculated for males, females, and for the whole study group. It was also determined whether there was an association between liver size and age, weight, height, body mass index (BMI), body surface area, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) enzyme levels. Results: The mean liver length was significantly different between males (150.04 ± 14.84) and females (147.57 ± 18.32, P = 0.034). Weight and BMI were the most strongly associated with liver size. There was a significant difference between liver size in individuals with normal and elevated levels of AST and ALT enzymes (P < 0.01). In a northern Anatolian Turkish population, liver size was greater among males than females. In light of these data, we believe our study may serve as a reference source for the evaluation of liver size.

A comparative and correlation study of electrocardiographic and echocardiographic left ventricular parameters in hypertension

Background: Routine echocardiographic assessment of left ventricular (LV) size and function in hypertensive individuals is desirable, but in resource-challenged African countries where this may be impracticable it is important to identify patients who after electrocardiographic (ECG) evaluation would benefit from further evaluation with echocardiography. Objective: To compare the echocardiographic parameters reflective of LV size and systolic function in hypertensive patients with normal ECG, LV hypertrophy (LVH) by voltage criteria only, and LVH with strain on electrocardiogram. Subjects and Methods: A cross-sectional comparative study of echocardiographic LV size and systolic function in hypertensive participants with normal ECG (60 participants), LVH with strain (51 participants), and LVH by voltage criteria only (50 participants) on ECG, attending the Cardiology Clinic of a University Teaching Hospital in Lagos, Nigeria. Results: ECG LVH with strain was associated with greater LVM index, higher prevalence of echocardiographic derived LVH, increased tendency toward hypertrophic LV geometric patterns, increased LV internal dimensions, LV systolic dysfunction, dilated left atrium and aortic root, as compared with ECG LVH by voltage criteria only and normal ECG in Nigerian hypertensive patients. Conclusion: ECG LVH with strain identifies a group of hypertensive individuals who are at increased cardiovascular risk and would benefit from further evaluation by echocardiography. Where echocardiography may not be readily accessible, this ECG pattern may aid decision making on appropriate therapeutic interventions.

Ecological and biological studies on five-lined skink, Trachylepis (= Mabuya) quinquetaeniata inhabiting two different habitats in Egypt.

This study was carried out to study the diet type, genetic, morphometric and histological variations between two natural populations of Trachylepis quinquetaeniata inhabiting Abu-Rawash, Embaba, North Giza and Garfas-Senoures, El-Faiyum habitats. In this study, morphometric examination showed that Trachylepis quinquetaeniata is a typically ground-dwelling Skink and seems to be frequently associated with grass and below shrubs. Geographic variation in sexual size dimorphism (SSD) and head size dimorphism (HSD) with greater dimensions in Garfas-Senoures, El-Faiyum compared with Abu-Rawash, Embaba, North Giza might be correlated with spatial food availability and abundance or micro-evolutionary change or phenotypic plasticity. Also, the increase of body size and mass in individuals from Garfas-Senoures, El-Faiyum might be an adaptation to lower ambient temperature and hypoxia. Diet analysis showed that the bulk of gut contents were beetles, plant bugs, hymenopterans and dipterans. The remainder of the plant material was probably ingested secondarily. Moreover, the increase in the activity of Ldh in liver tissues of T. quinquetaeniata inhabiting Abu-Rawash, Embaba, North Giza could be confirmed by the significant increase in the accumulation of the total lipids in liver and muscle tissues than that in the other population. As well as, a marked degeneration, necrosis and desquamation of spermatogoneal cells lining seminiferous tubules in testes of T. quinquetaeniata inhabiting Garfas-Senoures, El-Faiyum than that in the other population inhabiting Abu-Rawash, Embaba, North Giza that could be attributed to the bioaccumulation of soil heavy metals in testes. Higher carbohydrate accumulation in the former lizards' population was confirmed by the high availability and diversity of diet in El-Faiyum habitat. Thus we concluded that T. quinquetaeniata inhabiting Abu-Rawash, Embaba, North Giza is more active, energetic and adaptable in its habitat than T. quinquetaeniata inhabiting Garfas-Senoures, El-Faiyum.

Trans-Activation Response Element RNA is Detectable in the Plasma of a Subset of Aviremic HIV-1-Infected Patients.

Determining the HIV-1 reservoir size in infected individuals is of great importance for improvement of their treatment. Plasma trans-activation response element (TAR) RNA has been suggested as one of the possible biomarkers. TAR RNA is produced during non-processive transcription in HIV-1 productively infected and latent T cells. Here, plasma samples and paired exosome samples of 55 subjects from the observational SCOPE cohort were analysed for the presence of TAR RNA. First, a PCR-based assay was optimized, which provided 100% specificity and 100% sensitivity in differentiating HIV-1 infected non-controllers from uninfected individuals. Next, TAR RNA was detected in the plasma of 63% of aviremic HIV-1-infected patients, who were either treated with antiretroviral therapy or were elite controllers. Although TAR RNA levels did not correlate with patient gender, age, CD4 levels, CD8 levels, they tended to correlate with CD4/CD8 ratio (P = 0.047). This study is the first to investigate plasma TAR RNA in a relatively large cohort of HIV-1-infected patients. We additionally show that the TAR RNA molecules in the plasma of aviremic patients are not limited to exosomes.

The effects of supramaximal versus submaximal intensity eccentric training when performed until volitional fatigue.

Our purpose was to compare supramaximal versus submaximal intensity eccentric training performed until volitional fatigue. Thirty-two young adults (19 males) were randomized into one of three groups: (1) ECC110 performed eccentric (ECC) only contractions at 110% of concentric (CON) 1-repetition maximum (1RM); (2) ECC80 performed ECC only contractions at 80% of CON 1RM; (3) a control group. Training progressed from 3 to 6 sets of unilateral ECC training of the elbow flexors over 8weeks, with each set performed until volitional fatigue. Elbow flexors muscle thickness (via ultrasound) and 1RM were assessed pre- and post-training. Rating of perceived exertion (RPE) and muscle soreness was self-reported. Both ECC110 (+0.25cm) and ECC80 (+0.21cm) showed a greater post-training increase in muscle thickness compared to control (-0.01cm) (p<0.05), with no differences between ECC110 and ECC80. ECC80 (+1.23kg) showed a greater post-training increase in strength compared to control (p<0.05), while ECC110 (+0.76kg) had no significant difference post-training vs. control (-0.01kg). ECC80 had significantly lower average RPE scores than ECC110 (p<0.05). Both supramaximal intensity eccentric training and submaximal intensity eccentric training are effective for increasing muscle size, but submaximal eccentric training is perceived to require less exertion than supramaximal training. These findings suggest that submaximal eccentric training may be an ideal strategy to increase muscle size and strength in individuals whose needs warrant training at a lower level of exertion.

Minimal alteration in muscle lipid genes following stabilized weight loss.

Variations in skeletal muscle peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), carntine palmitoyltransferase-1 (CPT-1), perilipin protein 2 (PLIN2), and adipose tissue triglyceride lipase (ATGL), and comparative gene identification-58 (CGI-58) have been described as playing important roles in the metabolic regulation of lipid oxidation, and may influence intramyocellular lipid (IMCL) and muscle lipid droplet size (LDS). While acute changes in caloric balance and/or aerobic capacity may affect lipid metabolism, the influence of sustained weight loss derived from caloric restriction with weight loss (CWL) compared with exercise training with weight loss (EWL) on the abovementioned parameters has not been fully elucidated. Using a combination of metabolic feeding and/or supervised exercise training, we evaluated the influence of stabilized weight loss elicited by CWL compared with EWL without the confounding influence of acute alterations in caloric balance on molecular markers of mitochondrial metabolism and lipid droplet size in middle-aged overweight individuals with impaired glucose tolerance. There were no significant changes in PGC-1α, CPT-1, PLIN2, ATGL and, CGI-58 messenger RNA (mRNA) in CWL and EWL. While there were no changes in ATGL mRNA in CWL, there was a strong trend (P = 0.05) for the ΔATGL mRNA in EWL with stabilized weight loss. There were no significant changes in IMCL or LDS within skeletal muscle in CWL or EWL, respectively. In conclusion, under the conditions of chronic caloric balance following dietary or exercise-based interventions, mediators of mitochondrial function, IMCL and LDS, were largely unaffected. Future studies should focus on intervention-based changes in protein expression and/or phosphorylation and the relationship to physiological endpoints.

The effects of high intensity interval training on muscle size and quality in overweight and obese adults

ObjectivesDespite growing popularity of high intensity interval training (HIIT) for improving health and fitness, limited data exist identifying the effects of HIIT on muscle characteristics. The purpose of the current study was to investigate the effects of a 3-week HIIT intervention on muscle size and quality in overweight and obese men and women. DesignRandomized controlled trial. MethodsForty-four overweight and obese men and women (mean±SD; age: 35.4±12.3years; height: 174.9±9.7cm; weight: 94.6±17.0kg; %fat: 32.7±6.5%) completed the current study. During baseline and post testing, muscle cross sectional area (mCSA) and echo intensity (EI) were determined from a panoramic scan of the vastus lateralis obtained by B-mode ultrasonography. Body composition variables were measured using dual energy X-ray absorptiometry. Participants were randomized into either a 1:1 work-to-rest ratio HIIT group (SIT; n=16), a 2:1 work-to-rest ratio HIIT group (LIT; n=19), or control (CON; n=9). HIIT participants performed five, 2-min bouts (LIT) or 10, 1-min bouts (SIT) at 85–100% VO2peak for 9 sessions over three weeks. ResultsAnalysis of covariance demonstrated a significant increase in mCSA for SIT (p=0.038; change (Δ)=3.17±3.36cm2) compared to CON (Δ=−0.34±2.36cm2). There was no significant difference in EI across groups (p=0.672). ConclusionsHIIT may be an effective exercise modality to influence muscle size in overweight and obese individuals. Future studies should investigate muscle characteristics and remodeling in an overweight population following interventions of longer duration and varying work-to-rest protocols.

Flexibility of resource allocation in a hermaphroditic-gynomonoecious herb through deployment of female and male resources in perfect flowers.

It has been hypothesized that two flower types permit flexible allocation of resources to female and male functions, yet empirical evidence for the sex-allocation hypothesis remains scarce in gynomonoecious species. To characterize resource allocation to pistillate and perfect flowers and allocation of perfect flowers between gynomonoecious and hermaphroditic individuals, we examined the flexibility and whether female-biased allocation increases with plant size in the hermaphroditic-gynomonoecious herb Eremurus anisopterus. Frequency of gynomonoecious individuals, flower production, and plant size were investigated in different populations. Floral allocation was compared among the three flower types of E. anisopterus. Frequency of gynomonoecious plants varied from 2-17% in nine populations. Only larger plants produced female flowers at the bottom of racemes. Both female and perfect flower production tended to increase proportionately with plant size in gynomonoecious individuals. Female flowers did not produce less biomass than perfect flowers from hermaphroditic or gynomonoecious plants. However, both female and perfect flowers from gynomonoecious individuals had lighter stamen mass, but larger pistil mass, than perfect flowers from hermaphrodites. Although the prediction of an increase in female flower number with plant size was not observed in E. anisopterus, the flexibility of sex allocation in gynomonoecious species was confirmed in that gynomonoecious individuals had a female-biased floral allocation compared to hermaphroditic individuals. Such comparisons of gynomonoecious to hermaphroditic individuals permit us to unveil a sexual adjustment strategy: flexibility of sexual investments within plants.

Variability in response to albuminuria-lowering drugs: true or random?

Albuminuria-lowering drugs have shown different effect size in different individuals. Since urine albumin levels are known to vary considerably from day-to-day, we questioned whether the between-individual variability in albuminuria response after therapy initiation reflects a random variability or a true response variation to treatment. In addition, we questioned whether the response variability is drug dependent. To determine whether the response to treatment is random or a true drug response, we correlated in six clinical trials the change in albuminuria during placebo or active treatment (on-treatment) with the change in albuminuria during wash-out (off-treatment). If these responses correlate during active treatment, it suggests that at least part of the response variability can be attributed to drug response variability. We tested this for enalapril, losartan, aliskiren, atrasentan and paricalcitol. No correlation between the on- and off-treatment albuminuria change was observed in the placebo arm of all clinical trials (R2 <0.01). However, we observed significant associations between the on- and off-treatment response (R2 0.14 to 0.57; all P<0.015) for different albuminuria lowering drugs. Additionally, the albuminuria responses strongly correlated when the same individual was re-exposed to the same drug at the same dose: lisinopril 10mgday-1 (R2 =53%; P<0.01), losartan 50mgday-1 (R2 =63%; P<0.01). The degree of albuminuria lowering with antialbuminuric drugs varies between patients. This variability in response appears drug-class independent. Identifying which factors determine this initial short-term variation in drug response appears important since the degree of albuminuria lowering is related to subsequent long-term renoprotection.

Defective proviruses rapidly accumulate during acute HIV-1 infection.

Although antiretroviral therapy (ART) suppresses viral replication to clinically undetectable levels, HIV-1 persists in CD4+ T cells in a latent form not targeted by the immune system or ART1–5. This latent reservoir is a major barrier to cure. Many individuals initiate ART during chronic infection, and in this setting, most proviruses are defective6. However, the dynamics of the accumulation and persistence of defective proviruses during acute HIV-1 infection are largely unknown. Here we show that defective proviruses accumulate rapidly within the first few weeks of infection to make up over 93% of all proviruses, regardless of how early ART is initiated. Using an unbiased method to amplify near full-length proviral genomes from HIV-1 infected adults treated at different stages of infection, we demonstrate that early ART initiation limits the size of the reservoir but does not profoundly impact the proviral landscape. This analysis allows us to revise our understanding of the composition of proviral populations and estimate the true reservoir size in individuals treated early vs. late in infection. Additionally, we demonstrate that common assays for measuring the reservoir do not correlate with reservoir size. These findings reveal hurdles that must be overcome to successfully analyze future HIV-1 cure strategies.

Identification of differentially expressed genes associated with differential body size in mandarin fish (Siniperca chuatsi).

Body size is an obvious and important characteristic of fish. Mandarin fish Siniperca chuatsi (Basilewsky) is one of the most valuable perciform species widely cultured in China. Individual differences in body size are common in mandarin fish and significantly influence the aquaculture production. However, little is currently known about its genetic control. In this study, digital gene expression profiling and transcriptome sequencing were performed in mandarin fish with differential body size at 30 and 180days post-hatch (dph), respectively. Body weight, total length and body length of fish with big-size were significantly higher than those with small-size at both 30 and 180dph (P<0.05). 2171 and 2014 differentially expressed genes were identified between small-size and big-size fish at 30 and 180dph, respectively. RT quantitative PCR (qPCR) analysis showed that the differential expression of 10 selected genes in mandarin fish that went through the same training procedure. The genes were involved in the growth hormone-insulin-like growth factor axis, cell proliferation and differentiation, appetite control, glucose metabolism, reproduction and sexual size dimorphism pathways. This study will help toward a comprehensive understanding of the complexity of regulation of body size in mandarin fish individuals and provide valuable information for future research.

Feeding strategies of a small mammal (Phyllotis xanthopygus, Rodentia Cricetidae) at diverse altitudes in the Central Andes, Argentina

Knowledge of feeding habits not only contributes information related to the resources that individuals need to survive and breed, but also leads to insights about the interactions between a species and its environment. The optimal foraging theory explains diet selection by several attributes of the trophic scenario such as availability, diversity, quality and predictability of food. Other models propose that digestive tract mass increases under high metabolic demands by cold, affecting food choice and intake. Thus, diet selection emerges as a behavioural trait shaped by intrinsic and extrinsic factors. The goal of our study was to determine variation in the trophic scenario among sites at different elevations, as well as variation in phenotypic traits relevant to the nutritional and energy balance in Phyllotis xanthopygus. This small rodent is widely distributed along the Andes Mountains. We assessed diet selection and digestive tract size in individuals collected at three elevations across its distribution range. Results on dietary proportion of specific trophic categories (green parts, fruits and arthropods) showed that P. xanthopygus alternates between omnivory and granivory/frugivory. Richness, diversity and quality of the available resources evidenced a relatively low-quality trophic scenario at high altitude. Nevertheless, the diets built in by animals from diverse altitudes lacked differentiation in quality or diversity. P. xanthopygus seems to behaviourally compensate environmental variation to cope with nutritional requirements, by changing diet composition and proportion of items included. The resultant uniform diet quality is consistent with the absence of variation in the gastrointestinal tract size. Considering the spatial variability and seasonality of the region, a behavioural response is probably the most convenient strategy to overcome short-term environmental heterogeneity. In a plastic species such as P. xanthopygus, behaviour is a fundamental aspect to take into account by predictive models in the forecasts of climate change effects on biological diversity.