[Clinical features of non-cirrhotic portal hypertension in patients with common variable immunodeficiency].

We wished to summarize the clinical features of common variable immunodeficiency (CVID) complicated by non-cirrhotic portal hypertension (NCPH) and to deepen our understanding of it. The case data of CVID complicated with NCPH admitted to Peking Union Medical College Hospital from January 1983 to May 2021 were analyzed retrospectively to summarize their clinical characteristics. Six patients with CVID combined with NCPH (three of each sex; 16-45 years) were assessed. Four patients had portal hypertension. All patients had anemia, splenomegaly, a normal serum level of albumin and transaminases, and possibly increased levels of alkaline phosphatase and gamma-glutamyl transpeptidase. Two patients were diagnosed with esophagogastric fundic varices by gastroscopy. Two patients underwent splenectomy (which improved hematologic abnormalities partially). Four patients had autoimmune disease. Two cases were diagnosed with nodular regenerative hyperplasia (NRH) upon liver biopsy. Six patients were administered intravenous immunoglobulin-G (0.4-0.6 g/kg bodyweight) once every 3-4 weeks as basic therapy. Often, CVID complicated with NCPH has: (1) The manifestations of portal hypertension as the primary symptom. (2) Autoimmune-related manifestations. Imaging can provide important diagnostic clues. The etiology may be related to hepatic NRH and splenomegaly due to recurrent infections.

[Meta analysis of the prevalence and influencing factors of WMSDs among dentists in China].

Objective: To explore the relevant factors of work-related musculoskeletal disorders (WMSDs) among dentists through Meta analysis, providing a basis for the prevention and control of WMSDs among dentists. Methods: In April 2022, cross-sectional research literatures on the prevalence correlation of WMSDs among Chinese dentists were searched in databases such as China National Knowledge Infrastructure, Wanfang, VIP, PubMed, Web of Science, and Em Base database. The search was conducted from the establishment of the database until April 2022, literatures were selected using keywords such as musculoskeletal disorders and dentists. To extract gender, age, length of service, disease classification and other related influencing factors as indicator, and prevalence was selected as the outcome indicator. After evaluating the quality of the literatures, RevMan 5.3 software was used to calculate the combined RD (95%CI) values of the included literatures. Results: A total of 15 articles were included, with a total sample size of 3646 people. Meta analysis results showed that the prevalence of WMSDs among dentists in China was 80%, and the top three parts of the incidence rates were 65% of the waist, 58% of the neck, and 50% of the back. Gender, age, length of service, region and disease classification all increased the risk of WMSDs, and the combined effect size were 75%, 78%, 71%, 77% and 82% respectively (P<0.05) . Conclusion: The occurrence of WMSDs among dentists in China is related to multiple factors such as gender, age, length of service and disease classification. The above risk factors should be taken into account in the workplace and preventive measures should be actively implemented to prolong the working life of dentists.

[Full-field stimulus threshold testing for evaluation of the retinal function in patients with inherited retinal dystrophy].

Objective: To analyze the characteristics of full-field stimulus thresholds (FST) in patients with middle-and late-stage inherited retinal dystrophy (IRD), and to explore the feasibility of the FST test in evaluating the retinal function for IRD patients. Methods: It was a retrospective case series study. Twenty-eight patients with IRD whose full-field electroretinogram (ERG) results showed no electrical activity (20 patients) or a serious decrease in electrical activity (8 patients) were enrolled, including 17 males and 11 females, with a median age of 32 years. Ten normal controls were also enrolled. All eyes had a measurement of best corrected visual acuity (BCVA) and an ERG test. FST stimulated by red, blue and white lights were examined with an electrophysiological instrument. The decimal value of BCVA was converted to logarithm of the minimum angle of resolution. Data of the better eye of each participant were used for statistical analysis. Independent sample t-test was used to analyze the difference in FST among patients. Linear regression was used to analyze the correlation between FST, visual acuity and ERG amplitudes. Results: The BCVA of all eyes was 0.7±0.6. Under the stimulation of red, blue and white lights, the FST were(-27.0±7.1), (-47.4±12.2) and(-41.7±11.5) dB in the 8 eyes with decreased electrical activity, (-16.3±7.0), (-27.2±13.7) and(-23.5±12.5) dB in the 20 eyes with no electrical activity, and(-39.9±4.0), (-65.8±4.0) and(-58.5±3.4) dB in the 10 control eyes, respectively. The FST of IRD patients were higher than the normal controls. The FST with red, blue and white lasers in eyes with no electrical activity were higher than those with severely reduced electrical activity (t=-3.472, -3.506, -3.433; all P=0.002). The BCVA was not correlated with the FST under the red, blue and white light stimulation in eyes with a serious reduction in electrical activity (r=0.134, 0.011, 0.010; P=0.055, 0.601, 0.611). There was a linear correlation between the red light stimulus FST and the b-wave amplitude of flicker ERG response (r=-0.591, P=0.026), but there was no significant correlation between other amplitudes and FST. Conclusions: The FST test is a supplementary method to evaluate the retinal function of patients with middle-and late-stage IRD. It can quantitatively reflect the function of rod and cone cell system. As the retinal function of IRD patients decreases, the FST gradually increase.

[Effect of simulated occlusal force on periodontal ligament stem cells of the deciduous teeth at different stages of root absorption].

Objective: To explore the related mechanisms of biological root resorption in decidual teeth by studying the biological effect of simulated occlusal force on the periodontal ligament stem cells (PDLSC) at different stages of root absorption. Methods: According to the tooth type and root absorption degree, healthy retained deciduous incisors and healthy first premolars that needed to be removed for orthodontic treatment were collected and divided into three groups with six teeth in each group: the deciduous unabsorbed group (UN group), the absorbed group (R group) and the permanent teeth group (P group). PDLSC was isolated from periodontal ligament and cultured. PDLSC of three groups were loaded with dynamic pressure of 0-45, 0-90, 0-135, 0-180, 0-225 and 0-270 kPa, respectively. The proliferation ability was detected by cell counting kit-8 (CCK-8) technique on day 1 to day 7, respectively. The apoptosis levels of PDLSC after loading with dynamic pressure of 0-45, 0-90, 0-135, 0-180 and 0-225 kPa were observed by the flow cytometry. The changes of microfilaments were observed by fibrous actin (F-actin) staining after the cytokeleton was subjected to dynamic pressure of 0-90 kPa. Results: PDLSC of three groups exhibited various proliferation abilities to dynamic pressure. The A values in the UN group and R group were significantly higher than those in the P group and the difference was statistically significant (P<0.05). However, there was no significant difference between the UN group and the R group (P>0.05). The A values of PDLSC in UN group and R group under dynamic pressures of 0-45, 0-90, 0-135 and 0-180 kPa had no statistical significance compared with the control group unloading dynamic pressure (P>0.05). However, under 0-225 and 0-270 kPa dynamic pressures, the A values at the day 3 to day 7 were statistically significant (P<0.05). The A values of PDLSC in P group under 0-45, 0-90, 0-135, 0-180 and 0-225 kPa dynamic pressures for 1 to 7 days were no statistically significant difference compared with the control group (P>0.05). The A value in P group under the 0-270 kPa was statistically significant only on day 3 (1.386±0.131) and day 5 to day 7 (1.728±0.226, 2.029±0.168 and 2.263±0.210, respectively)(P<0.05). The result of apoptosis showed that the A values of PDLSC in UN group, R group and P group were significantly increased under 0-90, 0-135, 0-180 kPa and above dynamic pressures, respectively (P<0.05) compared with the control group unloading dynamic pressure. Under 0-90 kPa dynamic pressure, F-actin fluorescence staining samples in three groups all showed green filaments which were arranged along the long axis of the cells in the R group and the P group, while some fibers in the UN group were closely arranged and promoted stress fiber assembly. Conclusions: The biological characteristics of PDLSC at different root absorption stages were changed when they were stimulated by mechanical stress, and PDLSC of the deciduous teeth at the root unabsorption stage were more sensitive to mechanical stress stimulation.

Identification and molecular characterization of tea-oil camellia-associated totivirus 1.

A novel dsRNA virus was identified by high-throughput sequencing from tea oil trees in China. Its complete genome of 4714 bp contains two open reading frames (ORFs). ORF1 encodes a putative coat protein (CP) of 702 amino acids (aa), and ORF2 codes for an RNA-dependent RNA polymerase (RdRp) of 855 aa. The virus shares the highest aa sequence identity of 45.21% in RdRp with taro-associated totivirus L (MN_119621), a member of the genus Totivirus in the family Totiviridae. Phylogenetic analysis of the aa sequences of the RdRp places the new virus in a group with other totiviruses, suggesting that this virus, which is provisionally named "tea-oil camellia-associated totivirus 1", should be considered a member of the genus Totivirus.

Dispersion-managed technique in temporal-frequency measurement for MoTe2-based ultrafast laser.

Ultrafast phenomena exist widely in modern scientific research. The time scale of ultrafast phenomena is mostly in the order of picosecond, femtosecond, or even attosecond. Nowadays, it is still a major challenge to study these nonrepetitive transient processes. Here, a temporal-frequency measurement based on a dispersion-managed technique has been proposed for an MoTe2-based ultrafast laser. The temporal-frequency measurement comprises a laser diode, an optical switch, a section of tunable dispersion compensation fiber, and a three-port beam splitter. Resolution of the proposed measurement can be tuned in a wide range; further, the upper and lower resolution limits are numerically simulated. The proposed measurement is expected to be applied in ultrafast pulse detection due to its application in real-time measurement of ultrafast nonrepetitive signals.

[Clinical analysis of eosinophilic gastroenteritis in 71 children].

Objective: To summarize the clinical data including manifestations, diagnosis, treatment and prognosis of eosinophilic gastroenteritis (EGE) in children. Methods: A retrospective analysis was performed in 71 patients with pathologically proven EGE at Beijing Children's Hospital Affiliated to Capital Medical University from January 2008 to January 2017. Their clinical manifestations, laboratory and imaging examinations, endoscopic findings, histopathological examinations, and treatment were collected and analyzed. Results: Among 71 EGE cases, 47 (66%) cases were male and 24 (34%) cases were female, and the median age was 9.2 (0.2-16.5) years old. The main clinical manifestations included abdominal pain (76%, 54/71), vomiting (68%, 48/71), anorexia (54%, 38/71), weight loss (38%, 27/71), and diarrhea (37%, 26/71). There were 27 cases (38%) with a history of allergic diseases or family history. The median absolute value of eosinophil in peripheral blood of the 71 patients was 0.4 (0-36.8)×10(9)/L, and 27 cases (38%) showed an increase in eosinophil counts. Serum IgE was measured in 52 patients (104.3 (3.4- 3 000.0)×10(3) U/L), and 30 patients (58%) showed an increase in serum IgE. A large number of eosinophils ((41.0±8.5)/HP) were found in 3 patients' ascites. The endoscopic examination of upper gastrointestinal tract revealed hyperemic edema in 62 cases (87%), plaque in 44 cases (62%), erosion in 17 cases (24%) and ulceration in 16 cases (23%). Histopathologically, in 8 cases (11%) the disease involved both stomach and duodeneum, in 21 cases (30%) involved stomach only, and in 37 cases (52%) involved duodeneum only. In addition, in 6 cases (8%) the disease involved esophagus and in 10 cases (14%) involved colorectum. Microscopically, eosinophil counts averaged 67/HP, 33/HP, 40/HP and 38/HP in esophageal, gastric, duodenal and colorectal mucosa respectively. A total of 34 cases were treated with glucocorticoid, and all these patients had alleviation of symptoms, which occurred within 14.9 days on average, but EGE recurred in 11 cases (32%). Conclusions: The clinical symptoms and endoscopic findings of EGE are diverse and nonspecific. Histopathological examination of gastrointestinal mucosa is particularly important for the diagnosis. Glucocorticoid treatment is effective, but the patients with EGE are prone to relapse.

Relationship between Toll-like receptor 4 and type-2 diabetes mellitus complicated by tuberculosis.

OBJECTIVE: To investigate the association between single-nucleotide polymorphisms (SNPs) in the Toll-like receptor 4 (TLR4) gene (TLR4) and the relationship between SNPs and type-2 diabetes mellitus (T2DM) complicated by tuberculosis (TB) (T2DMTB) susceptibility. METHODS: The relationship between SNPs and T2DMTB was assessed using SNPstats (http://bioinfo.iconcologia.net/SNPstats). Generalised multifactor dimensionality reduction (GMDR) was used to select the best interaction combination of the four SNPs. Stratified analysis was performed using logistic regression. RESULTS: Logistic analysis showed that both rs11536889 and rs7873784 in TLR4 were associated with risk of T2DMTB in additive and dominant models. Carriers with homozygous and heterozygous mutants of rs11536889 and rs7873784 were associated with higher T2DMTB risk than those with wild-type homozygotes (OR 1.68, 95%CI 1.22-2.17 and OR 1.61, 1.18-2.09, respectively). GMDR analysis indicated a significant two-locus model (P = 0.0107) involving rs7873784 and rs11536889; the cross-validation consistency of this model was 9/10, and testing accuracy was 60.11%. Participants with rs7873784-GC/CC and rs11536889-GC/CC genotypes had the highest risk of T2DMTB compared with participants with rs7873784-GG and rs11536889-GG genotypes (OR 3.32, 95%CI 2.12-4.63). CONCLUSIONS: We found that> rs11536889 and rs7873784 in the TLR4 gene, and their interactions, were associated with increased T2DMTB risk.

The application value of continuous nursing for home oxygen therapy of patients in the stable phase of chronic obstructive pulmonary disease.

OBJECTIVE: To analyze the application value of continuous nursing in improving the effects of home oxygen therapy for patients in the stable phase of chronic obstructive pulmonary disease (COPD). PATIENTS AND METHODS: Patients in the stable phase of COPD (n=106) were selected and divided into the control group and observation group based on parity digit of their admission number. There were 53 cases in each group. The patients in the control group received COPD health education at discharge, while the observation group received continuous nursing. The effect of home oxygen therapy in both groups after 3 months was compared. RESULTS: The compliance in the observation group for home oxygen therapy was significantly higher than that in the control group. Blood gas analysis and various indicators of pulmonary function in the control group at follow-up visits were not changed compared with those before. In contrast, partial pressure of blood oxygen and blood oxygen saturation of the observation group were lower than those before discharge. With the increasing partial pressure of carbon dioxide in arterial blood, the indicators of pulmonary function became lower than before. Comparing the various indexes between both groups at follow-up visits, the differences were statistically significant (p<0.05). The self-care ability and quality of life scores of patients in the observation group were higher than those of the control group, and the differences were statistically significant (p<0.05). CONCLUSIONS: By establishing health records and network platforms, continuous nursing can provide continuous health education and supervision for patients with COPD, which can effectively improve oxygen therapy compliance, self-care ability and quality of life. It has good application and promotional value.

Discrete bisoliton fiber laser.

Dissipative solitons, which result from the intricate balance between dispersion and nonlinearity as well as gain and loss, are of the fundamental scientific interest and numerous important applications. Here, we report a fiber laser that generates bisoliton - two consecutive dissipative solitons that preserve a fixed separation between them. Deviations from this separation result in its restoration. It is also found that these bisolitons have multiple discrete equilibrium distances with the quantized separations, as is confirmed by the theoretical analysis and the experimental observations. The main feature of our laser is the anomalous dispersion that is increased by an order of magnitude in comparison to previous studies. Then the spectral filtering effect plays a significant role in pulse-shaping. The proposed laser has the potential applications in optical communications and high-resolution optics for coding and transmission of information in higher-level modulation formats.

Graphene-clad microfibre saturable absorber for ultrafast fibre lasers.

Graphene, whose absorbance is approximately independent of wavelength, allows broadband light-matter interactions with ultrafast responses. The interband optical absorption of graphene can be saturated readily under strong excitation, thereby enabling scientists to exploit the photonic properties of graphene to realize ultrafast lasers. The evanescent field interaction scheme of the propagating light with graphene covered on a D-shaped fibre or microfibre has been employed extensively because of the nonblocking configuration. Obviously, most of the fibre surface is unused in these techniques. Here, we exploit a graphene-clad microfibre (GCM) saturable absorber in a mode-locked fibre laser for the generation of ultrafast pulses. The proposed all-surface technique can guarantee a higher efficiency of light-graphene interactions than the aforementioned techniques. Our GCM-based saturable absorber can generate ultrafast optical pulses within 1.5 µm. This saturable absorber is compatible with current fibre lasers and has many merits such as low saturation intensities, ultrafast recovery times, and wide wavelength ranges. The proposed saturable absorber will pave the way for graphene-based wideband photonics.

Survival and associated mortality risk factors among post-treatment pulmonary tubercolosis patients in the northwest of China.

OBJECTIVE: The tuberculosis (TB) program was carried out in the Changji zone in northwest of China. Directly Observed Treatment, Short-Course (DOTS) is a modern control strategy against tuberculosis recommended by World Health Organization. The purpose of this work is to describe the survival of post-treatment TB (PTB) patients and to identify the risk factors associated with mortality and treatment outcomes, so that effective measures and interventions could be used to decrease the mortality rate. PATIENTS AND METHODS: Registry of 4501 TB patients at Center for Disease Control and Prevention (CDC) treated from 2007 to 2014 were collected. Mortality was used as an outcome measure and calculated per 100 person years of observation (PYO) from the date of completion of the treatment to the date of interview if the patients were alive or to the date of death. Kaplan-Meier and Cox regression methods were used to determine the survival and hazard ratios. An indirect method of standardization was used to calculate the standard mortality ratio (SMR). RESULTS: The average PYO was 5.0 and the total was 21851. Mortality per 100 PYO was 1.9/100 PYO [223/11871] for smear-positive, 3.4/100 PYO [305/9048] for smear-negative and 2.4/100 PYO [22/932] for EPTB cases. Univariate and Cox regression analysis showed that age (p < 0.01), education (p < 0.01), occupation (p < 0.01) and economic status (p < 0.01) were associated with increased mortality. DISCUSSION: Since the mortality rate was higher in Post-treatment TB patients than the general population these patients need special health care. An integrated survival and associated mortality risk factors and information system is necessary for TB surveillance, personal health status and treatment management. Further studies are required to identify the causes of death in these patients.

Management and maintenance of the airway in cervical necrotising fasciitis: a retrospective analysis of 15 cases.

Cervical necrotising fasciitis is a progressive deep infection of the neck associated with high mortality, and skillful management of the airway is critical for operations under general anaesthesia. Tracheostomy under local anaesthesia has been considered the gold standard of airway management in patients with deep neck infections, but it may be difficult or impossible in advanced cases. We report here our experience over 6 years (January 2008 and December 2013) during which a total of 15 patients was diagnosed with cervical necrotising fasciitis. Of 6 patients, admitted between January 2008 and March 2010, 5 had routine tracheostomy under local anaesthesia, 1 had direct laryngoscopy intubation, and 9 who were admitted between Spring 2010 and December 2013 were treated with nasotracheal intubation. Postoperatively all patients were given moderate sedation and analgesia. Nasotracheal intubation was continued until the infection had been controlled. During intubation patency of the endotracheal tube was maintained by humidification with a continuous pump of 0.45% sodium chloride and suction. All 15 patients (10 men and 5 women, mean age 62 years, range 36-93) required an emergency drainage procedure under general anaesthesia. Fourteen of the 15 had evidence of compromise of the airway, but emergency intervention was not required. Since Spring 2010, 9 consecutive patients had required nasotracheal intubation, including 7 video laryngoscopies and 2 fibreoptic bronchoscopies. No other interventions were required. Patients were intubated postoperatively from 3 to 14 days, and there were no problems with the airway. Advanced techniques for control of the airway have a high rate of success in patients with necrotising fasciitis and could be an appropriate alternative to a traditional airway. Postoperative sedation and analgesia should be considered as routine management of pain and anxiety.

Prevention and treatment of diarrhoea with Saccharomyces boulardii in children with acute lower respiratory tract infections.

The aim of this study was to determine whether Saccharomyces boulardii prevents and treats diarrhoea and antibiotic-associated diarrhoea (AAD) in children. A total of 333 hospitalised children with acute lower respiratory tract infection were enrolled in a 2-phase open randomised controlled trial. During the 1st phase, all children received intravenous antibiotics (AB). They were randomly allocated to group A (S. boulardii 500 mg/day + AB, n=167) or group B (AB alone, n=166) and followed for 2 weeks. Diarrhoea was defined as ≥3 loose/watery stools/day during at least 2 days, occurring during treatment and/or up to 2 weeks after AB therapy had stopped. AAD was considered when diarrhoea was caused by Clostridium difficile or when stool cultures remained negative. In the 2nd phase of the study, group B patients who developed diarrhoea were randomly allocated to two sub-groups: group B1 (S. boulardii + oral rehydration solution (ORS)) and group B2 (ORS alone). Data from 283 patients were available for analysis. Diarrhoea prevalence was lower in group A than in group B (11/139 (7.9%) vs. 42/144 (29.2%); relative risk (RR): 0.27, 95% confidence interval (CI): 0.1-0.5). S. boulardii reduced the risk of AAD (6/139 (4.3%) vs. 28/144 (19.4%); RR: 0.22; 95% CI: 0.1-0.5). When group B patients developed diarrhoea (n=42), S. boulardii treatment during 5 days (group B1) resulted in lower stool frequency (P<0.05) and higher recovery rate (91.3% in group B1 vs. 21.1% in B2; P<0.001). The mean duration of diarrhoea in group B1 was shorter (2.31±0.95 vs. 8.97±1.07 days; P<0.001). No adverse effects related to S. boulardii were observed. S. boulardii appeared to be effective in the prevention and treatment of diarrhoea and AAD in children treated with intravenous antibiotics.

Caffeine-stimulated fatty acid oxidation is blunted in CD36 null mice.

AIM: The increase in skeletal muscle fatty acid metabolism during exercise has been associated with the release of calcium. We examined whether this increase in fatty acid oxidation was attributable to a calcium-induced translocation of the fatty acid transporter CD36 to the sarcolemma, thereby providing an enhanced influx of fatty acids to increase their oxidation. METHODS: Calcium release was triggered by caffeine (3 mm) to examine fatty acid oxidation in intact soleus muscles of WT and CD36-KO mice, while fatty acid transport and mitochondrial fatty acid oxidation were examined in giant vesicles and isolated mitochondria, respectively, from caffeine-perfused hindlimb muscles of WT and CD36-KO mice. Western blotting was used to examine calcium-induced signalling. RESULTS: In WT, caffeine stimulated muscle palmitate oxidation (+136%), but this was blunted in CD36-KO mice (-70%). Dantrolene inhibited (WT) or abolished (CD36-KO) caffeine-induced palmitate oxidation. In muscle, caffeine-stimulated palmitate oxidation was not attributable to altered mitochondrial palmitate oxidation. Instead, in WT, caffeine increased palmitate transport (+55%) and the translocation of fatty acid transporters CD36, FABPpm, FATP1 and FATP4 (26-70%) to the sarcolemma. In CD36-KO mice, caffeine-stimulated FABPpm, and FATP1 and 4 translocations were normal, but palmitate transport was blunted (-70%), comparable to the reductions in muscle palmitate oxidation. Caffeine did not alter the calcium-/calmodulin-dependent protein kinase II phosphorylation but did increase the phosphorylation of AMPK and acetyl-CoA carboxylase comparably in WT and CD36-KO. CONCLUSION: These studies indicate that sarcolemmal CD36-mediated fatty acid transport is a primary mediator of the calcium-induced increase in muscle fatty acid oxidation.

Subcellular lipid droplet distribution in red and white muscles in the obese Zucker rat.

AIMS/HYPOTHESIS: Little is known about the subcellular distribution of lipids in insulin-resistant skeletal muscle. However, it has recently been suggested that lipid accumulation in the subsarcolemmal region directly contributes to insulin resistance. Therefore we hypothesised that regional differences in lipid distribution in insulin-resistant muscle may be mediated by: (1) a reduction in fatty acid trafficking into mitochondria; and/or (2) a regional increase in the enzymes regulating lipid synthesis. METHODS: Transmission electron microscopy was used to quantify lipid droplet and mitochondrial abundance in the subsarcolemmal and intermyofibrillar compartments in red and white muscles from lean and obese Zucker rats. To estimate rates of lipid trafficking into mitochondria, the metabolic fate of radiolabelled palmitate was determined. Key enzymes of triacylglycerol synthesis were also determined in each subcellular region. RESULTS: Subsarcolemmal-compartmentalised lipids represented a small absolute fraction of the overall lipid content in muscle, as regardless of fibre composition (red/white) or phenotype (lean/obese), lipid droplets were more prevalent in the intermyofibrillar region, whereas insulin-resistant white muscles were devoid of subsarcolemmal-compartmentalised lipid droplets. While, in obese animals, lipid droplets accumulated in both subcellular regions, in red muscle of these animals lipids only appeared to be trafficked away from intermyofibrillar mitochondria, a process that cannot be explained by regional differences in the abundance of triacylglycerol esterification enzymes. CONCLUSIONS/INTERPRETATION: Lipid accumulation in the subsarcolemmal region is not necessary for insulin resistance. In the intermyofibrillar compartment, the diversion of lipids away from mitochondria in insulin-resistant animals probably contributes to lipid accumulation in this subcellular area.

Antioxidant micronutrients improve intrinsic and UV-induced apoptosis of human lymphocytes particularly in elderly people.

OBJECTIVE: Aging and oxidative stress may lead to enhanced cellular damage and programmed cell death. To study the association of intrinsic apoptosis with age and the effect of antioxidant supplementation on intrinsic and UV-induced apoptosis in children, young and elderly people. METHODS: The study was a 2 months, double-blind, randomized trial. Three age groups were studied: children, young adults and elderly people. A total of 274 healthy subjects were allocated to a group supplemented with moderate amounts of retinol, ß-carotene, α-tocopherol, ascorbic acid and selenium or placebo. Plasma oxidative stress parameters were detected and apoptosis of lymphocytes was evaluated with TUNEL staining. RESULTS: At baseline, percentages of intrinsic apoptosis were 13.8% and 11.1% in elderly and young people, respectively, both significantly higher than children (6.3%). A decrease of 1.7% and 2.3% in intrinsic apoptosis of lymphocytes was found in the supplemented groups of young and elderly people compared with their control groups (all p values <0.001), but no significant decrease in children. Moreover, percentages UV-induced apoptosis significantly decreased by 1.4%, 1.9% and 3.1% in children, young and elderly people, respectively, compared with control groups after the trial. There were considerable increments in concentrations of plasma ß-carotene, retinol, tocopherol, ascorbic acid and selenium in all three treated groups after the supplementation. CONCLUSIONS: Young and elderly people have a higher intrinsic apoptosis than children, which was improved by antioxidant supplementation. UV-induced damage was attenuated by the supplementation in all three age groups.

Increased levels of peroxisome proliferator-activated receptor gamma, coactivator 1 alpha (PGC-1alpha) improve lipid utilisation, insulin signalling and glucose transport in skeletal muscle of lean and insulin-resistant obese Zucker rats.

AIMS/HYPOTHESIS: Reductions in peroxisome proliferator-activated receptor gamma, coactivator 1 alpha (PGC-1alpha) levels have been associated with the skeletal muscle insulin resistance. However, in vivo, the therapeutic potential of PGC-1alpha has met with failure, as supra-physiological overexpression of PGC-1alpha induced insulin resistance, due to fatty acid translocase (FAT)-mediated lipid accumulation. Based on physiological and metabolic considerations, we hypothesised that a modest increase in PGC-1alpha levels would limit FAT upregulation and improve lipid metabolism and insulin sensitivity, although these effects may differ in lean and insulin-resistant muscle. METHODS: Pgc-1alpha was transfected into lean and obese Zucker rat muscles. Two weeks later we examined mitochondrial biogenesis, intramuscular lipids (triacylglycerol, diacylglycerol, ceramide), GLUT4 and FAT levels, insulin-stimulated glucose transport and signalling protein phosphorylation (thymoma viral proto-oncogene 2 [Akt2], Akt substrate of 160 kDa [AS160]), and fatty acid oxidation in subsarcolemmal and intermyofibrillar mitochondria. RESULTS: Electrotransfection yielded physiologically relevant increases in Pgc-1alpha (also known as Ppargc1a) mRNA and protein ( approximately 25%) in lean and obese muscle. This induced mitochondrial biogenesis, and increased FAT and GLUT4 levels, insulin-stimulated glucose transport, and Akt2 and AS160 phosphorylation in lean and obese animals, while bioactive intramuscular lipids were only reduced in obese muscle. Concurrently, PGC-1alpha increased palmitate oxidation in subsarcolemmal, but not in intermyofibrillar mitochondria, in both groups. In obese compared with lean animals, the PGC-1alpha-induced improvement in insulin-stimulated glucose transport was smaller, but intramuscular lipid reduction was greater. CONCLUSIONS/INTERPRETATIONS: Increases in PGC-1alpha levels, similar to those that can be induced by physiological stimuli, altered intramuscular lipids and improved fatty acid oxidation, insulin signalling and insulin-stimulated glucose transport, albeit to different extents in lean and insulin-resistant muscle. These positive effects are probably attributable to limiting the PGC-1alpha-induced increase in FAT, thereby preventing bioactive lipid accumulation as has occurred in transgenic PGC-1alpha animals.