Association between body mass index and lumbar spine volumetric bone mineral density in diabetic and non-diabetic patients

BACKGROUND The association between body mass index(BMI)and bone mineral density(BMD)has shown inconsistent results,varying by sex and skeletal site.Despite normal or elevated bone mass,individuals with type 2 diabetes have an increased risk of hip and vertebral fractures.AIM To assess lumbar spine trabecular volumetric BMD(vBMD)across different BMI categories in individuals with and without diabetes.METHODS This cross-sectional study included 966 men over 50 years old and 1001 postmenopausal women from the Pinggu Metabolic Disease Study.The vBMD of lumbar vertebrae 2 through 4 was measured using quantitative computed tomography.Total adipose tissue,subcutaneous adipose tissue(SAT),visceral adipose tissue(VAT),and lumbar skeletal muscle area were also quantified.RESULTS In men with obesity(P=0.038)and overweight(P=0.032),vBMD was significantly higher in the diabetes group compared to non-diabetic men.After adjusting for age and sex,no significant saturation effect between BMI and BMD was found in participants with diabetes or in women without diabetes.However,a BMI threshold of 22.33 kg/m²indicated a saturation point for vBMD in nondiabetic men.Independent predictors of vBMD in men included age(r=-0.387,P<0.001),BMI(r=0.130,P=0.004),and VAT(r=-0.145,P=0.001).For women,significant predictors were age(r=-0.594,P<0.001),BMI(r=0.157,P=0.004),VAT(r=-0.112,P=0.001),and SAT(r=-0.068,P=0.035).CONCLUSION The relationship between BMI and trabecular vBMD differs in individuals with and without diabetes.Overweight and obese men with diabetes exhibit higher vBMD.

Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems

Atlantic salmon Salmo salar were reared at four stocking densities--high density D1 （final density -39 kg/m^3）, medium densities DE （-29 kg/m^3） and D3 （~19 kg/m^3）, and low density D4 （-12 kg/m^3）- for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight （SGRw） but did affect specific growth rate in terms of energy （SGRe）. Stocking density significantly influenced the ration level （RLw and RLe）, feed conversion ratio （FCRw and FCRe） and apparent digestibility rate （ADR）. Ration level and FCRw tended to increase with increasing density. Fish at the highest density D~ and lowest density D4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry.

Dosimetric Impact of Tumor Position and Lung Density Variations in Lung Stereotactic Body Radiotherapy

Purpose of this study was to evaluate the variation of the dose to gross tumor volume (GTV) related to tumor position and lung density for lung stereotactic body radiotherapy (SBRT) using a virtual phantom. The density of the equivalent lung surrounding the GTV (10 mm diameter) was defined as 0.10, 0.15, 0.25, 0.35, and 0.45 g/cm3. A planning target volume (PTV) was generated by adding a uniform 8 mm margin to the internal target volume (ITV). We defined that the 99% of the GTV should be covered by 100% of the prescribed dose using Monte Carlo (MC) calculation. The GTV structure was replicated from ITV to the PTV periphery at 1 mm intervals. Planned dose to the GTV was defined as the predicted dose in the replicated GTV structure. Simulated dose to the GTV was defined as the calculated dose in the replicated GTV structure taking into account the tumor position error. D99 of the planned dose to the GTV at the 8 mm shift position was 78.1%, 81.6%, 87.3%, 91.4% and 94.4% at equivalent lung densities of 0.10, 0.15, 0.25, 0.35, and 0.45 g/cm3, respectively. D99 of the simulated dose to the GTV at the 8 mm shift position was 96.9%, 95.3%, 94.2%, 95.1 % and 96.3% at equivalent lung densities of 0.10, 0.15, 0.25, 0.35, and 0.45 g/cm3, respectively. Planned dose to GTV is strongly dependent on lung density and tumor position errors, while simulated dose to GTV does not show any significant dependence.

Bone mineral density in Iranian patients: Effects of age, sex, and body mass index

Introduction: Osteoporosis is a multifactorial skeletal disease that is characterized by reduced bone mineral density (BMD). BMD values depend on several factors such as age, sex and age at menopause. The purpose of this study was to determine the prevalence and changes in bone mineral density in Iranian patients. Methods: Three hundred patients were selected through random sampling technique in 2009. BMD was assessed by Norland (Excell) technique at the lumbar and femoral neck. Weight and height were measured through standard methods. A thorough history was taken from each patient. The data was analyzed using SPSS software version 13.0. P-values less than 0.05 were considered statistically significant. Results: From among the 300 studied patients, 86.6% were female. their mean age was 52.7 years. Their average body mass index (BMI) was 28.14 kg/m2. Mean T-Score at lumbar spine and femoral neck was -1.07 ±1.19 and -1.75 ± 1.33 respectively. Mean BMD value at lumbar spine and femoral neck was 0.92 ± 0.19 and 0.77 ± 0.16 respectively. The prevalence of osteoporosis at lumbar spine and femoral neck was 33.7% and 16.7, respectively. There was a significant correlation between age, BMI and BMD values (P-Value Conclusion: This study shows that ageing and low BMI are risk factors associated with bone loss. it is recommended to measure BMD and implement prevention programs for high-risk people.

Effect of Stocking Density on Growth Performance, Production Trait, Food Utilization and Body Composition, of Meagre (Argyrosomus regius)

A 10-week rearing trial was conducted in cages with average initial weight of 9.15 ± 0.2 g/fish and average initial length of 9.2 ± 0.02 cm/fish of meagre, Argyrosomus regius, to examine the effect of three stocking density on growth performances, production traits, feed utilization and body composition. Nine cages 24 m3 each (4 × 6 × 1.5 m, long, width and height) were stocked with either 1200, 3600 and 6000 fish for each cage to give a stocking rate of 50, 150, and 250 fish/m3 respectively and fish fed daily, slightly in excess of satiation to eliminate the possibility of food supply being a limiting factor to growth. The results revealed that, mean final weight (g/fish), gain in weight, SGR (%per day), feed conversion ratio, protein efficiency ratio and total feed intake (g/fish) were significantly (P ≤ 0.01) influenced. The best at the lowest stocking density, while, the total production and net production exhibited significantly the opposite trend. Harvest and production estimates increased with increasing stocking density. Fish body composition% of moisture, protein, fat and ash were significantly (P ≤ 0.01) influenced by stocking density. From the above results and the economic information of the study, it can be concluded that stocking density of 50 fish/m3 of meagre exhibited the highest net profit and would seem to be the most desirable density in the system studied.

Effect of Stocking Density on Water Quality and(Growth, Body Composition and Plasma Cortisol Content) Performance of Pen-Reared Rainbow Trout(Oncorhynchus mykiss)

The goal of the study was to examine the effect of stocking density on the water quality of culture area, as well as the growth, body composition and cortisol content of rainbow trout(Oncorhynchus mykiss). Pen-reared trout were stocked in densities of 40, 60, 80 fish individuals m^(-3)(4.6, 6.6, 8.6 kg m^(-3), SD1, SD2 and SD3 groups, respectively) for 300 days. Compared to the water from SD1 and SD2, that from SD3 exhibited significantly higher NH_4^+-N content and COD(chemical-oxygen-demand), and a significant reduction of dissolved oxygen in day 180(40.6 kg m^(-3)). Stocking density was significantly associated with body weight, standard length, VSI(viscerosomatic index), CF(condition factor) and FC(food coefficient) in group SD3, particularly in day 240 and day 300(45 or 49.3 kg m^(-3)). Increased crude fat and decreased crude protein were displayed in high density group when the density reached to 36 kg m^(-3). As a cumulative effect of density-related stress, VSI, CF, FC, moisture, and crude protein content varied over time in each density group(SD1, SD2, and SD3). In summary, trout exhibited a better growth performance in low density(26.3 kg m^(-3)) than those reared in high densities(36 and 45 kg m^(-3)). The results indicate that rainbow trout(114.44 g ± 6.21 g, 19.69 cm ± 0.31 cm) initially stocked in 6.6 or 8.6 kg m^(-3) should be lightened to less than 36 kg m^(-3) after an intensive rearing for 240 days.

Quantitative Evaluation of Fat Composition in Lumbar Vertebral Body and Paraspinal Muscle by Proton Density Fat Fraction with MRI

Purpose: Bone marrow and muscle adiposity have been considered to correlate with osteoporosis and Sarcopenia. Proton Density Fat Fraction (PDFF) can be measured by Magnetic Resonance Imaging (MRI). The purpose of the present study was to measure PDFF in the lumbar spine, paraspinal muscle and subcutaneous fat tissue. Methods: Participants were comprised of 30 patients (18 males, 12 females;age range, 14 - 87 years) who underwent MRI due to low back symptoms. PDFFs for the body of the fourth lumbar vertebra (L4), paraspinal muscle, and subcutaneous fat were measured. Results: PDFFs of the vertebral body and subcutaneous fat were significantly higher than that of paraspinal muscle (p < 0.001). PDFF was significantly higher for subcutaneous fat than for the vertebral body (p < 0.001). Although no significant differences in PDFF of the vertebral body, paraspinal muscle, and subcutaneous fat between females and males, PDFFs of the vertebral body and paraspinal muscle were significantly higher in older subjects (>63 years) than in younger subjects (Conclusions: PDFF of the vertebral body was significantly higher than that of paraspinal muscle. PDFFs of the vertebral body and paraspinal muscle were significantly lower in younger subjects than in older subjects.

Reduced one-body density matrix of Tonks-Girardeau gas at finite temperature

With thermal Bose–Fermi mapping method, we investigate the Tonks–Girardeau gas at finite temperature. It is shown that at low temperature, the Tonks gas displays the Fermi-like density profiles, and with the increase in temperature, the Tonks gas distributes in wider region. The reduced one-body density matrix is diagonal dominant in the whole temperature region, and the off-diagonal elements shall vanish rapidly with the deviation from the diagonal part at high temperature.

High-energy fiber-shaped calcium-ion batteries enable integrated wearable electronics for human body monitoring

Electronic textiles hold the merits of high conformability with the human body and natural surrounding,possessing large market demand and wide application foreground in smart wearable and portable devices.However,their further application is largely hindered by the shortage of flexible and stable power sources with multifunctional designability.Herein,a free-standing ZnHCF@CF electrode(ZnHCF grown on carbon nanotube fiber)with good mechanical deformability and high electrochemical performance for aqueous fiber-shaped calcium ion battery(FCIB)is reported.Benefiting from the unique Ca^(2+)/H^(+)co-insertion mechanism,the ZnHCF@CF cathode can exhibit great ion storage capability within a broadened voltage window.By pairing with a polyaniline(PANI)@CF anode,a ZnHCF@CF//PANI@CF FCIB is successfully fabricated,which exhibits a desirable volumetric energy density of 43.2mWh cm^(-3)and maintains superior electrochemical properties under different deformations.Moreover,the high-energy FCIB can be harmoniously integrated with a fiber-shaped strain sensor(FSS)to achieve real-time physiological monitoring on knees during long-running,exhibiting great promise for the practical application of electronic textiles.

TyG-BMI、HAR、GRI与糖尿病视网膜病变的关系

目的探讨甘油三酯葡萄糖体重指数(TyG-BMI)、高密度脂蛋白胆固醇与载脂蛋白A比值(HAR)、血糖风险指数(GRI)与糖尿病视网膜病变(DR)的关系。方法将159例2型糖尿病(T2DM)并发DR患者(DR组)根据DR国际临床分级标准分为非增殖期视网膜病变组(NPDR组,66例)和增殖期视网膜病变组(PDR组,93例),另择159例未发生DR的T2DM患者为对照组。记录临床信息和基线实验室检查结果,计算TyG-BMI、HAR、GRI。多因素Logistic回归分析DR发病的影响因素,受试者工作特征(ROC)曲线分析TyG-BMI、HAR、GRI对DR的诊断价值。结果DR组T2DM病程,合并高血压、糖尿病肾病、糖尿病足比例,糖化血红蛋白(HbA1c)、稳态模型胰岛素抵抗指数(HOMA-IR)、总胆固醇(TC)、C反应蛋白(CRP)、TyG-BMI、HAR和GRI水平均高于对照组(P<0.05)。PDR组TyGBMI、HAR和GRI均高于NPDR组(P<0.05)。多因素Logistic回归分析结果显示,T2DM病程较长[OR(95%CI):2.781(1.398~5.534)]、高TyG-BMI[2.036(1.169~3.546)]、高HAR[1.890(1.090~3.280)]、高GRI[1.836(1.065~3.167)]是DR患病的危险因素(P<0.05)。ROC曲线分析结果显示,联合TyG-BMI、HAR、GRI诊断DR的曲线下面积(AUC)高于单独诊断[分别为0.940(0.908~0.964)、0.864(0.821~0.900)、0.796(0.747~0.839)、0.836(0.790~0.875),均P<0.05]。结论T2DM患者TyG-BMI、HAR、GRI增高与DR发病及病情严重程度有关,可用于评估DR的发病风险。

全身振动训练改善绝经后女性骨密度效果的Meta分析

目的:利用Meta分析评价全身振动训练对绝经后女性骨密度的影响。方法:以全身振动训练、绝经后女性、骨质疏松和骨密度等为主题词,检索中国知网、万方数据库、PubMed、Web of Science等数据库中关于全身振动训练提高绝经后女性骨密度的研究,检索时限为各数据库建库至2024-04-03,纳入指标包括:腰椎(L_1-L_4、L_2-L_4)、股骨颈、大转子、Ward三角和全身的骨密度,使用Revman 5.3和R 4.3.3进行数据分析。结果:(1)纳入文献共计28篇,均为随机对照研究;(2)振动强度:振动频率≥20 Hz且振幅≥2 mm能显著提升股骨颈、大转子、Ward区域、L_1-L_4和L_2-L_4腰椎骨密度(P<0.01,I~2<50%);(3)训练周期与频率:每周进行两三次训练,训练次数达到48-96次,各部位骨密度均显著提高(P<0.05,I~2<50%);(4)动作模式:动态训练能显著提高股骨颈(P=0.03,I~2=0%)、大转子(P<0.001,I~2=0%)和Ward区域(P<0.001,I~2=0%)骨密度,静蹲能显著提高L_1-L_4腰椎骨密度(P<0.001,I~2=0%),静态多种蹲姿能有效提升L_2-L_4腰椎(P<0.01,I~2=0%)和股骨颈(P=0.04,I~2=34%)骨密度。结论:全身振动训练在改善绝经后女性骨密度方面具有一定潜力,建议采用的振动频率和幅度不低于20 Hz和2 mm,训练次数不低于48次,提升腰椎骨密度宜采用静态训练,提升髋部骨密度宜采用动态训练。

Methods of predicting vertebral body fractures of the lumbar spine

Lumbar vertebral body(VB) fractures are increasingly common in an ageing population that is at greater risk of osteoporosis and metastasis. This review aims to identify different models, as alternatives to bone mineral density(BMD), which may be applied in order to predict VB failure load and fracture risk. The most representative models are those that take account of normal spinal kinetics and assess the contribution of the cortical shell to vertebral strength. Overall, predictive models for VB fracture risk should encompass a range of important parameters including BMD, geometric measures and patient-specific factors. As interventions like vertebroplasty increase in popularity for VB fracture treatment and prevention, such models are likely to play a significant role in the clinical decision-making process. More biomechanical research is required, however, to reduce the risks of post-operative adjacent VB fractures.

The Relationship between Bone Mineral Density and Obesity in Women

The aim of this study was to determine the relationship between obesity and osteoporosis. A total of 30 Saudi women, aged between 20 and 50 years, were selected randomly. We calculated each subject’s body mass index (BMI) and determined their lumbar and femur bone mineral densities using dual-energy X-ray absorptiometry (DXA). We examined the interaction between obesity and bone mineral density (BMD) using logistic regression, after adjusting for age, family history of osteoporosis, maternal fractures, smoking, and any sedentary lifestyles. BMI was shown to be the most effective independent variable with respect to bone density. We evaluated the Pearson correlation coefficients of BMI, BMD of the lumbar spine, and BMD of the femoral neck with reference to the variables of the study, and found a significant correlation (P 30 kg/m2) were at increased risk of osteoporosis at the femoral neck and severe osteopenia in the lumbar spine.

Numerical and theoretical investigations of the effect of the gangue-coal density ratio on the drawing mechanism in longwall top-coal caving

Discrete element calculations of the top-coal drawing process for diferent gangue-coal density ratios were conducted to investigate the efect of the gangue-coal density ratio on the drawing mechanism in longwall top-coal caving.The efects were analyzed for the drawing body,the top-coal boundary,and the recovery of top coal.The results show that for increasing density ratio,the initial drawing body on the goaf side is farther away from the drawing support and its width and volume gradually increase.The upper part of the sickle-shaped drawing body extends near the initial drawing body with increasing density ratio in the normal cycling stage,and the distance from the drawing body to the initial drawing body is its maximum width.The larger the density ratio,the smaller the height of the top coal above the goaf at the end of the initial drawing process.The height of the top-coal boundary decreases with increasing density ratio,until it reaches a limit.In a normal cycle,due to hysteretic development,the top-coal boundary moves toward the goaf until the density ratio is approximately 2.0,which is consistent with the physical experiment results.Finally,increasing the advance length of the working face is benefcial for increasing the overall recovery of top coal.

Discussion on the Relationship between Dieting and Bone Density among Female College Students and the Health Guidance

We studied the relationship between dieting and bone density among female college students and the current state thereof. Female college students are generally thin, with the time to giving birth and raising the next generation approaching. We expect the results of this study will be useful in improving health guidance. The subjects consisted of 124 female college students. Their average age was 21.4. The ultrasonic propagation velocity of the heel bone was measured as the bone density value. Body height, weight, and BMI (Body mass index) were also measured. Further, a multiple choice and short answer survey was conducted regarding their desire to be thin and dieting. Classifying the subjects by BMI, 16 students were underweight (13%), 102 students were of normal weight (84%), and 4 students were overweight (3%). 95% of those in the normal weight group had a desire to be thin, while 44% of the underweight group had a desire to be thin. Moreover, 31% of those in the normal weight group were currently on a diet, while 21% of the underweight group was also on a diet. The distribution of bone density (%YAM value: Young Adult Mean) was as follows: 61 students (49%) were in the high density group (≥100);58 students (47%) were in the middle density group (≥80 - <100);and 5 students (4%) were in the low density group (<80). The more the bone density decreased, the greater the proportion of students with dieting experience. Among students with no dieting experience, the %YAM value was high when the BMI value was high. All of the students in the low density group had a desire to be thin, even though their bone density was low. Students who do not need to be thin had a desire to be thin and were considering continuing dieting going forward. Moreover, some students fell into the %YAM low density group, which is worrisome for the future. It is believed necessary to reinforce health guidance regarding dieting and bone density in school education. In particular, it is necessary to improve guidance since we observed a lack of knowledge regarding osteoporosis prevention.

BONE MINERAL ANALYSIS OF WHOLE BODY IN 292 NORMAL SUBJECTS ASSESSED BY DUAL X-RAY ABSORPTIOMETRY

Objective. To study the whole body bone mineral changes in normal subjects.Methods. Bone mineral was measured by dual X-ray absorptiometry(DXA) in 292 normal subjectsaged 10～79 years, including 152 females and 140 males. They were divided into age-groups by decade.Results. In males, the ages with peak value of total bone mineral content (TBMC), total bone min-eral density (TBMD), anteroposterior spine BMD(L2-4 BMD) were in the 30～39,20～39, 20～29 age-groups respectively. In females, they were all in the 30～39 age-group. Peak values of TBMC, TBMD,L2-4 BMD were higher in males than those in females. Loss of bone mineral for females was more pro-nounced than that for males. Loss of L2-4 BMD was more pronounced than TBMD.Conclusion. This study provides the normal bone mineral data of whole body for males and females,and the characteristic of changes.

Hepatitis C virus clearance and less liver damage in patients with high cholesterol, low-density lipoprotein cholesterol and APOE ε4 allele

BACKGROUND Cholesterol is related to improvements in the rate of sustained virological response and a robust immune response against the hepatitis C virus(HCV).APOE gene polymorphisms regulate cholesterol levels modifying the course of the HCV infection.The relationship between cholesterol,APOE alleles,and the outcome of HCV infection has not been evaluated in the admixed population of Mexico.AIM To investigate the role of APOE-ε2,-ε3,and-ε4 alleles and the metabolic profile in the outcome of HCV infection.METHODS A total of 299 treatment-na?ve HCV patients were included in this retrospective study.Patients were stratified in chronic hepatitis C(CHC)(n=206)and spontaneous clearance(SC)(n=93).A clinical record was registered.Biochemical tests were assessed by dry chemistry assay.APOE genotypes were determined using a Real-Time polymerase chain reaction assay.RESULTS Total cholesterol,low-density lipoprotein cholesterol(LDL-c),triglycerides,and hypercholesterolemia were higher in SC than CHC patients as well as the frequency of the APOEε4 allele(12.4%vs 7.3%).SC patients were overweight(54.8%).Theε4 allele was associated with SC(OR=0.55,95%CI:0.31-0.98,P=0.042)and mild fibrosis(F1-F2)in CHC patients(OR 0.091,95%CI 0.01-0.75,P=0.020).LDL-c≥101.5 mg/dL(OR=0.20,95%CI:0.10-0.41,P<0.001)and BMI≥26.6 kg/m2(OR=0.37,95%CI:0.18-0.76,P<0.001)were associated with SC status;while ALT≥50.5 IU/L was negatively associated(OR=5.67,95%CI:2.69-11.97,P<0.001).CONCLUSION In SC patients,the APOEε4 allele and LDL-c conferred a protective effect in the course of the HCV infection in the context of excess body weight.

Factors associated with trabecular bone score in postmenopausal women with type 2 diabetes and normal bone mineral density

BACKGROUND Osteoporosis and type 2 diabetes(T2D)have been recognized as a widespread comorbidity leading to excess mortality and an enormous healthcare burden.In T2D,bone mineral density(BMD)may underestimate the risk of low-energy fractures as bone quality is reduced.It was hypothesized that a decrease in the trabecular bone score(TBS),a parameter assessing bone microarchitecture,may be an early marker of impaired bone health in women with T2D.AIM To identify clinical and body composition parameters that affect TBS in postmenopausal women with T2D and normal BMD.METHODS A non-interventional cross-sectional comparative study was conducted.Potentially eligible subjects were screened at tertiary referral center.Postmenopausal women with T2D,aged 50-75 years,with no established risk factors for secondary osteoporosis,were included.BMD,TBS and body composition parameters were assessed by dual-energy X-ray absorptiometry.In women with normal BMD,a wide range of anthropometric,general and diabetes-related clinical and laboratory parameters were evaluated as risk factors for TBS decrease using univariate and multivariate regression analysis and analysis of receiver operating characteristic(ROC)curves.RESULTS Three hundred twelve women were initially screened,176 of them met the inclusion criteria and underwent dual X-ray absorptiometry.Those with reduced BMD were subsequently excluded;96 women with normal BMD were included in final analysis.Among them,43 women(44.8%)showed decreased TBS values(≤1.31).Women with TBS≤1.31 were taller and had a lower body mass index(BMI)when compared to those with normal TBS(Р=0.008 and P=0.007 respectively).No significant differences in HbA1c,renal function,calcium,phosphorus,alkaline phosphatase,PTH and 25(ОН)D levels were found.In a model of multivariate linear regression analysis,TBS was positively associated with gynoid fat mass,whereas the height and androgen fat mass were associated negatively(all P<0.001).In a multiple logistic regression,TBS≤1.31 was associated with lower gynoid fat mass(adjusted odd ratio[OR],0.9,95%confidence interval[CI],0.85-0.94,P<0.001),higher android fat mass(adjusted OR,1.13,95%CI,1.03-1.24,P=0.008)and height(adjusted OR,1.13,95%CI,1.05-1.20,P<0.001).In ROC-curve analysis,height≥162.5 cm(P=0.04),body mass index≤33.85 kg/m2(P=0.002),gynoid fat mass≤5.41 kg(P=0.03)and android/gynoid fat mass ratio≥1.145(P<0.001)were identified as the risk factors for TBS reduction.CONCLUSION In postmenopausal women with T2D and normal BMD,greater height and central adiposity are associated with impaired bone microarchitecture.

Age-Related Surface Oxidases Shed into Body Fluids as Targets to Prevent Skin Aging and Reduce Cardiovascular Risk

Age-related Ecto-Nicotinamide Adenine Dinucleotide Oxidase Disulfide Thiol Exchangers 3 (ENOX3) or age-related NADH oxidases (arNOX) are expressed at the cell surface as five members of the TM-9 superfamily, initially membrane anchored, all functionally similar, with the N-termini exposed at the cell’s exterior. ECTO-NOXes are cell surface proteins with both time-keeping CoQH2 [NAD(P)H] oxidase and protein disulfidethiol interchange activities. They are designated as ECTO-NOX proteins because of their localization on the outer surface of the plasma membrane and to distinguish them from the phox-NOXes of host defense. A ca. 30 kDa N-terminal fragment is cleaved and accumulates in body fluids (serum, saliva, urine, perspiration). arNOXes appear around age 30 and increase steadily thereafter. Reduced quinones, i.e., reduced coenzyme Q, of the plasma membrane are natural substrates. NAD(P)H is oxidized as an artificial substrate. In one phase of the arNOX cycle electrons are transferred to oxygen to generate superoxide. Substrates for the shed forms of arNOX appear to be proteins of body fluids. Circulating lipoproteins and skin matrix proteins emerge as potentially important health-related targets. Through oxidation of collagen, elastin and other proteins of the skin matrix, arNOXes are major contributors to skin aging through tyrosine and thiol oxidation and subsequent cross linking. The main destructive action of arNOX, however, may be to directly oxidize circulating lipoproteins. arNOX in the blood is structured as an integral component of the LDL particle through site-specific binding. As such, arNOXes are implicated as major risk factors for cardiovascular disease due to specific oxidation of LDLs. The superoxide produced and its conversion to hydrogen peroxide would be one part of the potentially destructive properties by contribution to lipid oxidation. Inhibition of arNOX proteins provides a rational basis for anti-aging interventions and their elimination as a major risk factor of atherogenesis.

Overweight and abdominal fat are associated with normal bone mineral density in patients with ulcerative colitis

BACKGROUND Low bone mineral density(BMD)is common in patients with inflammatory bowel disease.However,nutritional risk factors for low BMD in the ulcerative colitis(UC)population are still poorly understood.AIM To investigate the association of anthropometric indicators and body composition with BMD in patients with UC.METHODS This is a cross-sectional study on adult UC patients of both genders who were followed on an outpatient basis.A control group consisting of healthy volunteers,family members,and close people was also included.The nutritional indicators evaluated were body mass index(BMI),total body mass(TBM),waist circumference(WC),body fat in kg(BFkg),body fat in percentage(BF%),trunk BF(TBF),and also lean mass.Body composition and BMD assessments were performed by dual-energy X-ray absorptiometry.RESULTS The sociodemographic characteristics of patients with UC(n=68)were similar to those of healthy volunteers(n=66)(P>0.05).Most patients(97.0%)were in remission of the disease,58.8%were eutrophic,33.8%were overweight,39.0%had high WC,and 67.6%had excess BF%.However,mean BMI,WC,BFkg,and TBF of UC patients were lower when compared to those of the control group(P<0.05).Reduced BMD was present in 41.2%of patients with UC(38.2%with osteopenia and 2.9%with osteoporosis)and 3.0%in the control group(P<0.001).UC patients with low BMD had lower BMI,TBM,and BFkg values than those with normal BMD(P<0.05).Male patients were more likely to have low BMD(prevalence ratio[PR]=1.86;95%confidence interval[CI]:1.07-3.26).Those with excess weight(PR=0.43;95%CI:0.19-0.97)and high WC(PR=0.44;95%CI:0.21-0.94)were less likely to have low BMD.CONCLUSION Patients with UC in remission have a high prevalence of metabolic bone diseases.Body fat appears to protect against the development of low BMD in these patients.