GHS-R suppression in adipose tissues protects against obesity and insulin resistance by regulating adipose angiogenesis and fibrosis

BACKGROUND/OBJECTIVES

Ghrelin is an orexigenic hormone that increases food intake, adiposity, and insulin resistance through its receptor Growth Hormone Secretagogue Receptor (GHS-R). We previously showed that ghrelin/GHS-R signaling has important roles in regulation of energy homeostasis, and global deletion of GHS-R reduces obesity and improves insulin sensitivity by increasing thermogenesis. However, it is unknown whether GHS-R regulates thermogenic activation in adipose tissues directly.

METHODS

We generated a novel adipose tissue-specific GHS-R deletion mouse model and characterized the mice under regular diet (RD) and high-fat diet (HFD) feeding. Body composition was measured by Echo MRI. Metabolic profiling was determined by indirect calorimetry. Response to environmental stress was assessed using a TH-8 temperature monitoring system. Insulin sensitivity was evaluated by glucose and insulin tolerance tests. Tissue histology was analyzed by hematoxylin/eosin and immunofluorescent staining. Expression of genes involved in thermogenesis, angiogenesis and fibrosis in adipose tissues were analyzed by real-time PCR.

RESULTS

Under RD feeding, adipose tissue-specific GHS-R deletion had little or no impact on metabolic parameters. However, under HFD feeding, adipose tissue-specific GHS-R deletion attenuated diet-induced obesity and insulin resistance, showing elevated physical activity and heat production. In addition, adipose tissue-specific GHS-R deletion increased expression of master adipose transcription regulator of peroxisome proliferator-activated receptor (PPAR) γ1 and adipokines of adiponectin and fibroblast growth factor (FGF) 21; and differentially modulated angiogenesis and fibrosis evident in both gene expression and histological analysis.

CONCLUSIONS

These results show that GHS-R has cell-autonomous effects in adipocytes, and suppression of GHS-R in adipose tissues protects against diet-induced obesity and insulin resistance by modulating adipose angiogenesis and fibrosis. These findings suggest adipose GHS-R may constitute a novel therapeutic target for treatment of obesity and metabolic syndrome.

Bis-Indole-Derived NR4A1 Ligands and Metformin Exhibit NR4A1-Dependent Glucose Metabolism and Uptake in C2C12 Cells

Treatment of C2C12 muscle cells with metformin or the NR4A1 ligand 1,1-bis(3'-indolyl)-1-(p-hydroxyphenyl)methane (DIM-C-pPhOH) induced NR4A1 and Glut4 messenger RNA and protein expression. Similar results were observed with buttressed (3- or 3,5-substituted) analogs of DIM-C-pPhOH, including 1,1-bis(3'-indolyl)-1-(3-chloro-4-hydroxy-5-methoxyphenyl)methane (DIM-C-pPhOH-3-Cl-5-OCH3), and the buttressed analogs were more potent than DIM-C-pPhOH NR4A1 agonists. Metformin and the bis-indole substituted analogs also induced expression of several glycolytic genes and Rab4, which has previously been linked to enhancing cell membrane accumulation of Glut4 and overall glucose uptake in C2C12 cells, and these responses were also observed after treatment with metformin and the NR4A1 ligands. The role of NR4A1 in mediating the responses induced by the bis-indoles and metformin was determined by knockdown of NR4A1, and this resulted in attenuating the gene and protein expression and enhanced glucose uptake responses induced by these compounds. Our results demonstrate that the bis-indole-derived NR4A1 ligands represent a class of drugs that enhance glucose uptake in C2C12 muscle cells, and we also show that the effects of metformin in this cell line are NR4A1-dependent.

[A therapeutic effect analysis of femur first principle and combined anteversion technique during total hip arthroplasty]

Objective: To investigate the situation of hip dislocation with the application of "femur first" principle and "combined anteversion technique" during total hip arthroplasty. Methods: A retrospective analysis has been done on the clinical data about 104 patients(133 hips)who were diagnosed as hip disease and were treated with total hip arthroplasty by the doctors from the Department of Joint Orthorpaedics of Shandong Provincial Hospital Affiliated to Shandong University from June 2014 to June 2016, and all the prostheses applied in the operation were cementless ones.Among them, 65 patients were males, 39 females and their age was 46.6 years (ranging from 23 to 76 years) .And 29 of them underwent bilateral hip operations and 75 unilateral ones.Seventy-six cases of aseptic necrosis of the femoral head in the terminal stage, 28 cases of hip dysplasia and osteoarthritis.Surgical approach: of all the operations, 103 hips were operated on with hardinge approach, 30 with posterolateral approach.During the operation, first of all, the femoral medullary cavity was broached and then the anteversion of intramedullary broacher was measured.After that, the anteversion of the acetabular cup was calculated as 37° minus the anteversion of the broacher, and the acetabular cup was implanted at that angle.The patients' prosthesis combined anteversion, range of motion of the hip joint, operation time, hemorrhage amount, and complications had been kept record.One, three, and six months respectively after the operation, all the patients received outpatient review, and took anteroposterior and lateral position X-ray examination.Harris hip score had been applied to evaluate their hip function before the operation and six months after the operation. Results: All the patients had been operated on smoothly, with the operation time of(57.6±14.5)minutes(36-115 minutes)and hemorrhage amount of (336.5±50.8)ml(180-620 ml). The operation finding showed that the combined anteversion by employing"femur first"principle and combined anteversion techniqueis was (36.6±6.8)°. Also, range of motion of the patients' hip conforms to the D'Lima criterion and no patients had experienced dislocation and some other serious complications.The follow-up ended at August 2017, which lasted for 12.2 months(6-18 months), and 88 cases(119 hips) were interviewed. The Harris hip score for the affected sides of the hip joints 6 months after the surgery was 94.6(86-100). Compared with the score of 29.8(12-43) before surgery, the t-test had proven its statistical significance(t=12.82, P=0.003). Conclusion: Based upon the "femoral first" principle and "combined anteversion technique" during total hip arthroplasty, these operations has been carried out well enough to meet the patients' needs of performing normal daily activities.

Diode-pumped orthogonally polarized self-mode-locked Nd:YLF lasers subject to gain competition and thermal lensing effect

The stable condition for π-polarization emission in an a-cut Nd:YLF laser is numerical analyzed to find the critical pump power for generating the orthogonally polarized emission. With the numerical analysis, an orthogonally polarized SML lasers at wavelength of 1047 nm and 1053 nm is experimentally achieved in a simple concave-plano cavity without any additional optical element. It is experimentally observed that the polarization switching and coexistence was successfully demonstrated by introducing gain competition and anisotropic thermal lens effect. In the orthogonal polarization mode-locked operation, the pulse durations are found to be 19.1 and 18.8 ps for π- and σ-polarization with pulse repetition rates of 3.85 and 3.89 GHz, respectively.

Comparison of two methods for RNA extraction from the nucleus pulposus of intervertebral discs

RNA extraction from the nucleus pulposus of intervertebral discs has been extensively used in orthopedic studies. We compared two methods for extracting RNA from the nucleus pulposus: liquid nitrogen grinding and enzyme digestion. The RNA was detected by agarose gel electrophoresis, and the purity was evaluated by absorbance ratio using a spectrophotometer. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) expression was assayed by reverse transcription-polymerase chain reaction (RT-PCR). Thirty human lumbar intervertebral discs were used in this study. The liquid nitrogen-grinding method was used for RNA extraction from 15 samples, and the mean RNA concentration was 491.04 ± 44.16 ng/mL. The enzyme digestion method was used on 15 samples, and the mean RNA concentration was 898.42 ± 38.64 ng/mL. The statistical analysis revealed that there was a significant difference in concentration between the different methods. Apparent 28S, 18S, and 5S bands were detectable in RNA extracted using the enzyme digestion method, whereas no 28S or 18S bands were detected in RNA extracted using the liquid nitrogen-grinding method. The GAPDH band was visible, and no non-specific band was detected in the RT-PCR assay by the enzyme digestion method. Therefore, the enzyme digestion method is an efficient and easy method for RNA extraction from the nucleus pulposus of intervertebral discs for further intervertebral disc degeneration-related studies.

Hypersingular meshless method using double-layer potentials for three-dimensional exterior acoustic problems

Three-dimensional exterior acoustic problems with irregular domains are solved using a hypersingular meshless method. In particular, the method of fundamental solutions (MFS) is used to formulate and analyze such acoustic problems. It is well known that source points for MFS cannot be located on the real boundary due to the singularity of the kernel functions. Thus, the diagonal terms of the influence matrices are unobtainable when source points are located on the boundary. An efficient approach is proposed to overcome such difficulties, when the MFS is used for three-dimensional exterior acoustic problems. This work is an extension of previous research on two-dimensional problems. The solution of the problem is expressed in terms of a double-layer potential representation on the physical boundary. Three examples are presented in which the proposed method is compared to the MFS and boundary element method. Good numerical performance is demonstrated by the proposed hypersingular meshless method.

Comparison of amoxicillin + clavulanate with or without intranasal fluticasone for the treatment of uncomplicated acute rhinosinusitis in children

AIM

Intranasal corticosteroids (INS) have been proven effective in controlling postnasal drip, decreasing inflammatory response, reducing nasal swelling, and increasing aeration of the sinuses such that INS are recommended as treatment of sinusitis.

METHODS

Fifty children with acute rhinosinusitis, 50 children with acute rhiniosinusitis and allergic rhinitis (AR), and 20 rhiniosinusitis children as control were selected for investigation. Each group had a single-blind treatment of three types: with coamoxiclav only, with coamoxiclav plus INS, and with matched placebo (without antibiotics and INS) for two weeks. Nasal symptoms were then evaluated. The outcome was measured by using major symptom score (MSS) after treatment for 14 days.

RESULTS

Therapeutic effectiveness was 92% in rhinosinusitis patients treated with co-amoxiclav and 84% in those treated with co-amoxiclav plus INS. Among patients with sinusitis combined with AR, therapeutic efficacy was 88% for those treated with co-amoxiclav and 96% for those treated with co-amoxiclav plus INS. Only 30% of the symptoms were reduced in the placebo group.

CONCLUSION

There are no statistical differences in the acute sinusitis group treated with co-amoxiclav with or without INS. In the sinusitis with AR group, the efficacy of co-amoxiclav with INS is higher than in children treated with co-amoxiclav alone.

Mapping forested wetlands in the Great Zhan River Basin through integrating optical, radar, and topographical data classification techniques

Knowledge of the spatial extent of forested wetlands is essential to many studies including wetland functioning assessment, greenhouse gas flux estimation, and wildlife suitable habitat identification. For discriminating forested wetlands from their adjacent land cover types, researchers have resorted to image analysis techniques applied to numerous remotely sensed data. While with some success, there is still no consensus on the optimal approaches for mapping forested wetlands. To address this problem, we examined two machine learning approaches, random forest (RF) and K-nearest neighbor (KNN) algorithms, and applied these two approaches to the framework of pixel-based and object-based classifications. The RF and KNN algorithms were constructed using predictors derived from Landsat 8 imagery, Radarsat-2 advanced synthetic aperture radar (SAR), and topographical indices. The results show that the objected-based classifications performed better than per-pixel classifications using the same algorithm (RF) in terms of overall accuracy and the difference of their kappa coefficients are statistically significant (p<0.01). There were noticeably omissions for forested and herbaceous wetlands based on the per-pixel classifications using the RF algorithm. As for the object-based image analysis, there were also statistically significant differences (p<0.01) of Kappa coefficient between results performed based on RF and KNN algorithms. The object-based classification using RF provided a more visually adequate distribution of interested land cover types, while the object classifications based on the KNN algorithm showed noticeably commissions for forested wetlands and omissions for agriculture land. This research proves that the object-based classification with RF using optical, radar, and topographical data improved the mapping accuracy of land covers and provided a feasible approach to discriminate the forested wetlands from the other land cover types in forestry area.

Decline of Yangtze River water and sediment discharge: Impact from natural and anthropogenic changes

The increasing impact of both climatic change and human activities on global river systems necessitates an increasing need to identify and quantify the various drivers and their impacts on fluvial water and sediment discharge. Here we show that mean Yangtze River water discharge of the first decade after the closing of the Three Gorges Dam (TGD) (2003–2012) was 67 km³/yr (7%) lower than that of the previous 50 years (1950–2002), and 126 km³/yr less compared to the relatively wet period of pre-TGD decade (1993–2002). Most (60–70%) of the decline can be attributed to decreased precipitation, the remainder resulting from construction of reservoirs, improved water-soil conservation and increased water consumption. Mean sediment flux decreased by 71% between 1950–1968 and the post-TGD decade, about half of which occurred prior to the pre-TGD decade. Approximately 30% of the total decline and 65% of the decline since 2003 can be attributed to the TGD, 5% and 14% of these declines to precipitation change, and the remaining to other dams and soil conservation within the drainage basin. These findings highlight the degree to which changes in riverine water and sediment discharge can be related with multiple environmental and anthropogenic factors.

Development of KMnO(4)-releasing composites for in situ chemical oxidation of TCE-contaminated groundwater

The objective of this study was to develop a controlled-oxidant-release technology combining in situ chemical oxidation (ISCO) and permeable reactive barrier (PRB) concepts to remediate trichloroethene (TCE)-contaminated groundwater. In this study, a potassium permanganate (KMnO4)-releasing composite (PRC) was designed for KMnO4 release. The components of this PRC included polycaprolactone (PCL), KMnO4, and starch with a weight ratio of 1.14:2:0.96. Approximately 64% (w/w) of the KMnO4 was released from the PRC after 76 days of operation in a batch system. The results indicate that the released KMnO4 could oxidize TCE effectively. The results from a column study show that the KMnO4 released from 200 g of PRC could effectively remediate 101 pore volumes (PV) of TCE-contaminated groundwater (initial TCE concentration = 0.5 mg/L) and achieve up to 95% TCE removal. The effectiveness of the PRC system was verified by the following characteristics of the effluents collected after the PRC columns (barrier): (1) decreased TCE concentrations, (2) increased ORP and pH values, and (3) increased MnO2 and KMnO4 concentrations. The results of environmental scanning electron microscope (ESEM) analysis show that the PCL and starch completely filled up the pore spaces of the PRC, creating a composite with low porosity. Secondary micro-scale capillary permeability causes the KMnO4 release, mainly through a reaction-diffusion mechanism. The PRC developed could be used as an ISCO-based passive barrier system for plume control, and it has the potential to become a cost-effective alternative for the remediation of chlorinated solvent-contaminated groundwater.

Attention deficit hyperactivity disorder and autism spectrum disorder in children born to mothers with thyroid dysfunction: a Danish nationwide cohort study

OBJECTIVE

To examine the association between maternal hyper- and hypothyroidism and the risk of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in the child.

DESIGN

A population-based cohort study.

SETTING

Singletons liveborn in Denmark between 1991 and 2004.

POPULATION

A total of 857 014 singletons alive and living in Denmark at the age of 3 years.

METHODS

Information on the diagnosis and/or treatment of maternal thyroid disease and the neurodevelopmental disorders ADHD and ASD in the child was obtained from Danish nationwide registers. The Cox proportional hazards model was used to estimate the hazard ratio (HR) with 95% confidence interval (95% CI) for risk of ADHD and ASD in children born to mothers with thyroid dysfunction, adjusting for potential confounding factors.

MAIN OUTCOME MEASURES

ADHD and ASD in the child.

RESULTS

Altogether, 30,295 singletons (3.5%) were born to mothers with thyroid dysfunction. Maternal hyperthyroidism diagnosed and treated for the first time after the birth of the child increased the risk of ADHD in the child (adjusted HR 1.23; 95% CI 1.05-1.44), whereas hypothyroidism increased the risk of ASD (adjusted HR 1.34; 95% CI 1.14-1.59). No significant association was seen for maternal diagnosis and treatment prior to the birth of the child.

CONCLUSIONS

Children born to mothers diagnosed and treated for the first time for thyroid dysfunction after their birth may have been exposed to abnormal levels of maternal thyroid hormone already present during the pregnancy, and this untreated condition could increase the risk of specific neurodevelopmental disorders in the child.

Incidence and risk of central nervous system metastases as site of first recurrence in patients with HER2-positive breast cancer treated with adjuvant trastuzumab

BACKGROUND

Central nervous system (CNS) disease as the site of first relapse after exposure to adjuvant trastuzumab has been reported. We carried out comprehensive meta-analysis to determine the risk of CNS metastases as the first site of recurrence in patients with HER2-positive breast cancer who received adjuvant trastuzumab.

METHODS

Eligible studies include randomized trials of adjuvant trastuzumab administered for 1 year to patients with HER2-positive breast cancer who reported CNS metastases as first site of disease recurrence. Statistical analyses were conducted to calculate the incidence, relative risk (RR), and 95% confidence intervals (CIs) using fixed-effects inverse variance and random-effects models.

RESULTS

A total of 9020 patients were included. The incidence of CNS metastases as first site of disease recurrence in HER2-positive patients receiving adjuvant trastuzumab was 2.56% (95% CI 2.07% to 3.01%) compared with 1.94% (95% CI 1.54% to 2.38%) in HER2-positive patients who did not receive adjuvant trastuzumab. The RR of the CNS as first site of relapse in trastuzumab-treated patients was 1.35 (95% CI 1.02-1.78, P = 0.038) compared with control arms without trastuzumab therapy. The ratio of CNS metastases to total number of recurrence events was 16.94% (95% CI 10.85% to 24.07%) and 8.33% (95% CI 6.49% to 10.86%) for the trastuzumab-treated and control groups, respectively. No statistically significant differences were found based on trastuzumab schedule or median follow-up time. No evidence of publication bias was observed.

CONCLUSIONS

Adjuvant trastuzumab is associated with a significant increased risk of CNS metastases as the site of first recurrence in HER2-positive breast cancer patients.

Magnetic field enhanced resonant tunneling in a silicon nanowire single-electron-transistor

We report fabrication, measurement and simulation of silicon single-electron-transistors made on silicon-on-insulator wafers. At T-2 K, these devices showed clear Coulomb blockade structures. An external perpendicular magnetic field was found to enhance the resonant tunneling peak and was used to predict the presence of two laterally coupled quantum dots in the narrow constriction between the source-drain electrodes. The proposed model and measured experimental data were consistently explained using numerical simulations.

Genetic polymorphism in milk fat globule-EGF factor 8 (MFG-E8) is associated with systemic lupus erythematosus in human

Milk fat globule-EGF factor 8 (MFG-E8) is a molecule implicated in phagocytic clearance of apoptotic cells by bridging between macrophages and apoptotic cells. Defects in MFG-E8 cause lupus-like disease in murine models. The aim of our study is to determine whether genetic variation in MFG-E8 predisposes human to systemic lupus erythematosus (SLE). A case-control study of MFG-E8 genetic polymorphism was performed on 147 SLE patients and 146 non-lupus control subjects. Single nucleotide polymorphisms (SNPs) in the coding sequence of human MFG-E8 gene were investigated. SNPs on MFG-E8 residues 3 (3(Arg or Ser)) and 76 (76(Leu or Met)) did not show genetic linkage. Genetic polymorphism on MFG-E8 residue 76 correlated significantly to SLE. The MFG-E8-76(Met) allele predisposed subjects to SLE in a recessive mode (odds ratio: 2.1, P = 0.020), while carriage of MFG-E8-76(Leu) were negatively associated with SLE. The MFG-E8 genotypic combinations with 3(Ser) and 76(Leu) showed the most pronounced protective effect on SLE when compared to the most predisposing genotype 3(Arg/Arg)-76(Met/Met) (OR: 0.29, P = 0.007). According to our result, MFG-E8 is associated with SLE predisposition in Taiwanese. Our study implicates that the impairment of phagocytic clearance of apoptotic cells through phosphotidylserine-dependent MFG-E8 system may lead to the development of human SLE.

Nonlinear saturation of cyclotron maser instability associated with energetic ring-beam electrons

We study the cyclotron maser instability (CMI) driven by an energetic ring-beam distribution by a particle simulation to explain possible generation mechanisms of intense radiation phenomena observed in space. The main objective is to understand the nonlinear processes that control saturation of the emission process. Our study reveals new issues that have been overlooked in past literature. It is found that electrostatic wave modes excited by the electron beam instability compete with the electromagnetic waves excited by the CMI. Nonlinear effects of these electrostatic modes tend to redistribute the energy of the energetic electrons and make the physics more complicated. The CMI can be much less effective in a realistic case than it is anticipated theoretically.

Proton heating via nonresonant scattering off intrinsic Alfvénic turbulence

A novel yet unsophisticated theory is proposed to show that low-beta protons can be efficiently heated by enhanced Alfvén waves. The present research is motivated by a plasma physics issue relevant to the explanation of hot stellar coronas observed with x-ray telescopes. The efficient heating is attributed to nonresonant wave-particle scattering that tends to randomize proton motion in directions transverse to the ambient magnetic field.

Prevalence of dementia in rural China: impact of age, gender and education

OBJECTIVE

To determine the prevalence of dementia and Alzheimer's disease (AD) in rural China.

METHODS

A cross-sectional study was conducted within a cohort of adults older than 50 years of age in Linxian County, China. A Chinese version of the Mini-Mental State Examination (CMMSE) was used to screen cases of possible dementia. Three different cutoff points on CMMSE were applied depending on the participant's level of education. The participants then were given psychiatric interviews, medical and neurological examinations, and psychometric tests to ascertain the clinical diagnoses of dementia and AD.

RESULTS

Among the 16,095 participants, 5.26% were screened positive with 374 diagnosed as having dementia. Among them, AD accounted for 80.5%. The adjusted prevalence rates were 0.33%, 0.89%, 3.43%, and 8.19% in people in age groups 50-54, 55-64, 65-74, and 75 and above, respectively. The prevalence of AD correlated with the participant's level of education, and was 2.61%, 0.94%, and 0.56% in the illiterate group, in the primary school group, and in the middle school or higher group, respectively. Adjusted by education levels a higher prevalence in women was observed in the illiterate group.

CONCLUSIONS

The prevalence of dementia in this population is similar to that reported from other areas in mainland China and Taiwan with aging being a significant risk factor. After controlling for age, being a female and having received less number of years of education were associated with an higher prevalence of AD.

Heating of ions by Alfvén waves via nonresonant interactions

Finite-amplitude intrinsic Alfvén waves exist pervasively in astrophysical and solar-terrestrial environment. It is generally believed that linear wave-particle resonant interaction between thermal protons and Alfvén waves is ineffective when the proton beta is low. However, this Letter demonstrates that the ions can be heated by Alfvén waves via nonresonant nonlinear interaction. Contrary to the customary expectation, it is found that the lower the plasma beta value, the more effective is the heating process. It is also shown that the ion temperature increase is more prominent along perpendicular direction.

Microbial activity in a combined UASB-activated sludge reactor system

A combined upflow anaerobic sludge bed-activated sludge (UASB-AS) reactor system with consistently wasting of excess biomass was used to treat suspended-solids pre-settled piggery wastewater (COD=2000 mg l(-1), total Kjeldahl nitrogen TKN=400 mg l(-1), suspended solids=250-400 mg l(-1)). Thus, the activity of nitrogen-related microbial groups in each individual bioreactor was investigated. When the granules retention time (GRT) of 20-50 d in the UASB reactor, the solids retention time (SRT) of 10-25 d in the AS reactor and the recycle-to-influent ratio (Re) of 1 were maintained, the combined system removed 95-97% of chemical oxygen demand (COD), 100% of TKN and 54-55% of total nitrogen (TN). Denitrification and methanogenesis occurred in the UASB reactor so that both biochemical processes contributed to most of the COD removal and, complete nitrification (most of the TKN removal) occurred in the AS reactor. Compact granules with good settling abilities developed in the UASB reactor, and rapid rates of granulation of break-up granules in the UASB reactor were confirmed by experiments. The activity of nitrifiers and denitrifiers (an=0.68-0.87; adn=0.55-0.70) and the calculated specific nitrification and denitrification rates (qn=0.26-0.47 mg NH4+ -N mg VSS(-1)d(-1); qdn=0.046-0.076 mg NOx- -N mg VSS(-1)d(-1)) significantly increased with decreasing SRT and GRT, respectively. Accordingly, the combined UASB-AS reactor system should be regarded a promising alternative for the removal of organic carbon and nitrogen from piggery wastewater.

Evidence for suppression of superconductivity by spin imbalance in Co-Al-Co single-electron transistors

Spin imbalance can lead to suppression of superconductivity. We report the phenomena manifesting this effect under spin-polarized quasiparticle currents in ferromagnet-superconductor-ferromagnet single-electron transistors. The measured superconducting gap as a function of magnetic field reveals a dramatic decrease when the magnetizations of the two leads are misaligned. The effect of suppression increases with increasing source-drain voltage. A comparison with theoretical calculations is presented. This method may render it applicable to control superconductivity at low temperatures within low fields.

Long-term alterations in body weight do not affect the expression of melanocortin receptor-3 and -4 mRNA in the ovine hypothalamus

The pro-opiomelanocortin-derived peptides and the melanocortin receptors are implicated in various functions within the CNS including the regulation of food intake. In the present study, we used in situ hybridization, with specific 35S-labelled ovine riboprobes to map the expression of melanocortin receptor-3 (MC3-R) and -4 (MC4-R) mRNA in the diencephalon and brainstem of normal female sheep. Furthermore, we examined the effect of long-term alterations in energy balance on the distribution and expression of MC3-R and MC4-R mRNA in food-restricted and ad libitum-fed ovariectomized female sheep. The distribution of melanocortin receptors generally resembled that of the rat. A high number of MC3-R-labelled cells were seen in the ventral division of the lateral septum and the medial preoptic area. In the hypothalamus, a moderate number of MC3-R-labelled cells was observed in the lateral hypothalamic area while other nuclear groups had low to intermediate numbers of MC3-R-labelled cells. The distribution of MC4-R mRNA was generally similar to that of MC3-R mRNA in the septal/preoptic and hypothalamic regions, with a high number of labelled cells present in the intermediate division of the lateral septum. Within the hypothalamus, no MC4-R mRNA expression was observed in the arcuate nucleus. There was more widespread distribution of moderate to low numbers of MC4-R mRNA-expressing cells in the brainstem compared to that of MC3-R mRNA. Unlike findings in the rat, only a low number of cells expressed melanocortin receptor mRNA in the ovine hypothalamic nuclei associated with feeding behavior. The number of melanocortin receptor-labelled cells and the level of expression (silver grains/cell) in the hypothalamic feeding centers was similar in food-restricted and ad libitum-fed animals. These findings suggest that long-term alterations in metabolic status do not change the melanocortin receptor mRNA distribution and/or expression in the sheep hypothalamus.

Mouse melanocortin-4 receptor gene 5'-flanking region imparts cell specific expression in vitro

Weight homeostasis is exquisitely sensitive to changes in the abundance of melanocortin-4 receptor (MC4-R). To begin to understand the factors that regulate MC4-R gene expression, we determined there are no introns in the gene, there are multiple starts of transcription, and a cluster of 3' ends. A series of MC4-R-luciferase gene reporter chimerics was developed and transfected into cell lines expressing (UMR106; GT1-7; HEK293) and not expressing (Neuro 2A) endogenous MC4-R mRNA. The longest construct, which includes approximately 3.3 kb 5'-flanking, 425 bp 5'-untranslated (UTR) and 1852 bp 3'-flanking, significantly increased luciferase reporter gene expression 24-, 13-, and 3-fold compared to pGL3-basic when expressed in HEK293, UMR106, and GT1-7 cells, respectively. Deletion analysis of mMC4-R 5'-flanking cDNA identified full mMC4-R promoter activity within 178 bp upstream of the major start of transcription. The mMC4-R gene structure and reporter chimerics provide a fundamental framework for the identification of specific factors regulating MC4-R gene expression.

Effect of addition of Rhodobacter sp. to activated-sludge reactors treating piggery wastewater

Under aerobic conditions, the decay rates of purple nonsulfur bacteria (Rhodobacter sp.) in the light and dark follow first-order kinetics with rate constants of 0.22 and 0.32 day(-1), respectively. The performance of the conventional activated-sludge reactor (CASR) treating anaerobically pretreated piggery wastewater (656-1.110 mg chemical oxygen demand, COD/L) can be enhanced by the addition of Rhodobacter sp. By performing regressive and statistical analyses using the proposed model and experimental data, the kinetic constants k and Y(T), and the fraction of refractory organic materials (f) of the Rhodobacter sp.-supplemented activated-sludge reactor (RASR) are 40% larger, 21% less, and 34% less than those of the CASR, respectively. From parametric sensitivity analyses, the substrate removal efficiencies of the CASR and RASR are most sensitive to the parameters k and the food to microorganisms ratio (F/M) but least sensitive to the parameter f; the specific oxygen utilization rates of the CASR and RASR are most sensitive to the parameters a and k but least sensitive to the parameter b.

Cordyceps sinensis and its fractions stimulate MA-10 mouse Leydig tumor cell steroidogenesis

The effects of Cordyceps sinensis (CS) and its extracted fractions on steroidogenesis in MA-10 cells were determined. Different concentrations of CS and 3 fractions of CS (F1, a water-soluble polysaccharide; F2, a water-soluble protein; and F3, a poorly water-soluble polysaccharide and protein) were added to MA-10 mouse Leydig tumor cells with or without human chorionic gonadotropin (hCG), and the production of steroid and the expression of steroidogenic acute regulatory protein (StAR) were examined. The results showed that CS alone (2-10 mg/mL) stimulated MA-10 cell progesterone production in a dose-dependent relationship. Fractions F1 and F3 (2-10 mg/mL) also had significant (P < .05) stimulatory effects on MA-10 cell steroidogenesis with a dose-dependent relationship. However, fraction F2 did not have an effect on MA-10 cells. CS and F3, but not F1, significantly induced more steroid production in hCG-stimulated MA-10 cells (P < .05). As a temporal relationship, F1 and F3 (2 mg/mL) maximally stimulated progesterone production between 1 and 3 hours after stimulation in MA-10 cells. In addition, CS and F3 significantly enhanced MA-10 cell StAR protein expression, which indicates that CS and F3 may use a cyclic adenosine monophosphate signal transduction pathway to activate MA-10 Leydig cell steroidogenesis in a manner to that of luteinizing hormone.

Magnifying colonoscopy in differentiating neoplastic from nonneoplastic colorectal lesions

OBJECTIVE

Because the medical management of persons with adenomatous colorectal polyps differs from that of those with hyperplastic polyps, accuracy of diagnosis is essential. This study reports our experience using a magnifying colonoscope combined with indigocarmine dye to diagnose colorectal polyps, emphasizing its ability to differentiate neoplastic from nonneoplastic lesions.

METHODS

The materials consisted of 175 polyps. A 0.2% indigocarmine solution was sprayed, and the colonoscope zoom apparatus performed a magnified observation after an ordinary colonoscopy identified the lesions. The pit patterns were classified into six categories: I, II, III(L), IIIs, IV, and V according to Kudo's modified classification.

RESULTS

The percentages of neoplastic changes in the lesions with pit pattern I, II, III(L), IIIs, IV, and V were 0, 12.2, 69.7, 80, 84.4, and 100%, respectively. The diagnostic sensitivity of neoplastic lesions was 93.8% and specificity was 64.6% when types I and II represented the pit pattern of nonneoplastic lesions and types III(L), IIIs, IV, and V represented neoplastic lesions. The overall diagnostic accuracy in differentiating neoplastic from nonneoplastic lesions was 80.1%. The diagnostic accuracy is not influenced by the size and shape of the lesions. The six neoplastic lesions that were misjudged to be nonneoplastic were histologically adenoma with only mild atypia.

CONCLUSIONS

The pit pattern analysis of colorectal lesions by magnifying colonoscopy is a useful and objective tool for differentiating neoplastic from nonneoplastic lesions of the large bowel. In its current state of development, however, this technique is not a substitute for histology.

Endoscopic treatment of colorectal polyps and early cancer

To analyze the efficacy and outcome of colonoscopic resection for colorectal neoplastic lesions, we retrospectively reviewed 338 colorectal lesions from 232 patients regarding the clinical profiles, colonoscopic findings, histological findings, complications, and outcome. Morphologically, these lesions were classified into three categories: pedunculated (n = 140), sessile (n = 176); and flat (n = 22). Histological findings of lesions included adenoma (n = 248), carcinoma in situ (n = 17), submucosal carcinoma (n = 2), hyperplastic polyp (n = 57), and inflammatory polyp (n = 14). Neoplastic lesions are generally larger than nonneoplastic lesions (chi2 test, P < 0.05). The incidence of carcinoma was 5.6% of 338 resected lesions. The rate of cancer or high-grade dysplasia in flat polyps was greater than in pedunculated and sessile polyps (13.6 vs 4.54 vs 5.71%; P < 0.05). There were no perforations or deaths after colonoscopic treatment, and only mild bleeding occured in two patients. To date, 19 patients with early colorectal cancer were treated successfully by endoscopy with no recurrence or metastasis. To reduce the incidence and mortality of colorectal cancer, colonoscopic resection is a simple and safe procedure for removing neoplastic lesions. Detailed histological examinations are essential to decide the indications of surgery.

Esophageal cancer after endoscopic injection sclerotherapy for esophageal varices

We reported two cases of squamous cell carcinoma of the esophagus following endoscopic injection sclerotherapy (EIS) for esophageal varices. Both patients were cigarette smokers and had a long history of alcohol abuse. HBsAg and Anti-HCV were negative, and Anti-HBs was positive in one of the patients. They were diagnosed as alcoholic cirrhosis with esophageal varices and received EIS treatment. Sotradecol was utilized as the sclerosant with a mean total volume of around 30 ml. Patients developed dysphagia at 5 and 48 months following EIS, respectively. Endoscopic examination showed stenosis and ulcerative mass at the lower portion of the esophagus. Biopsy revealed well- to moderately differentiated squamous cell carcinoma of the esophagus. We conclude that endoscopic follow-up is essential and carcinoma of the esophagus should be included in the differential diagnosis for esophageal ulceration and dysphagia following EIS, particularly in those patients with risk factors for developing esophageal carcinoma.

Melatonin inhibits the expression of steroidogenic acute regulatory protein and steroidogenesis in MA-10 cells

The effects of melatonin on steroidogenesis and steroidogenic acute regulatory (StAR) protein expression were investigated in MA-10 mouse Leydig tumor cells. MA-10 cells were treated with human chorionic gonadotropin/cyclic adenosine monophosphate (hCG/cAMP) analogue alone or with hCG/cAMP analogue plus melatonin in different dosages (0.1 nM to 10 microM). Steroid production and the expression of StAR protein were measured. Melatonin directly inhibited hCG- or dbcAMP-stimulated progesterone production in MA-10 cells within 3 hours. The inhibitory effects of melatonin on hCG- or dbcAMP-stimulated steroid production in MA-10 cells were abolished by a comparative melatonin receptor antagonist, luzindole. 22R-hydroxycholesterol reversed melatonin's inhibitory effects, which illustrated that melatonin did not suppress P450scc enzyme activity. Moreover, StAR protein expression stimulated by hCG and dbcAMP was maximally reduced by 10 nM of melatonin treatment for 3 hours. The effects of prolonged exposure (12 h) to melatonin with dbcAMP stimulation in MA-10 cells were also examined. The expression of StAR protein and steroid production were reduced by melatonin concentrations from 1 nM to 10 microM. However, melatonin at a dose of 1 nM had no effect in 3-hour treatment. Our results indicate that melatonin suppressed MA-10 mouse Leydig cell steroidogenesis through specific binding sites by blocking StAR protein expression without altering the activity of P450scc enzyme.

Risk factors for colorectal adenomas among immediate family members of patients with colorectal cancer in Taiwan: a case-control study

OBJECTIVES

The incidence of colorectal cancer or adenoma among first-degree relatives of patients with colorectal cancer is significantly high. However, a well defined screening and surveillance consensus has not been developed for these families in Taiwan. We conducted this study to evaluate the colorectal adenoma prevalence pattern in screened immediate family members in Taiwan, and to derive implications for future screening programs.

METHODS

A total of 234 immediate family members (aged 51.6 +/- 21.5 yr) of 186 patients with colorectal cancer were offered a colonoscopy. Each relative examined was then paired with two control subjects for age, sex, and symptoms. The prevalence of colorectal adenomas was then compared using multiple logistic regression analysis.

RESULTS

The estimated risk of developing adenomas among immediate family members of patients with colorectal cancer was significantly increased (OR = 2.33; 95% CI, 1.43-3.78; p < 0.001). This trend was more striking for men (OR = 2.46; 95% CI, 1.40-4.31; p = 0.001). Immediate family members were at an increased risk for high-risk adenomas (> or = 1.0 cm, with a villous component, and/or with severe dysplasia) (OR = 4.5; 95% CI, 1.91-10.60; p = 0.002), and developed adenomas at an earlier age than did controls. Individuals with index cancer relatives diagnosed at < 50 yr of age or male relatives posed a higher risk of developing colorectal adenomas.

CONCLUSIONS

The prevalence of colorectal adenoma in persons with a colorectal cancer family history in Taiwan is similar to that reported in Western countries. This high-risk population should be offered a screening colonoscopy beginning at 40 yr of age.

Lower-dose (13)C-urea breath test to detect Helicobacter pylori infection-comparison between infrared spectrometer and mass spectrometry analysis

BACKGROUND

The expense of the (13)C-urea breath test (UBT) to detect Helicobacter pylori infection is mainly due to the cost of (13)C-urea and the analysis using isotope ratio mass spectrometry (IRMS).

AIM

To test whether a UBT, using a lower dose of urea and lower-priced isotope-selective nondispersive infrared spectrometry (INIS), can preserve diagnostic efficacy in clinical practice.

METHODS

A total of 177 dyspeptic patients received endoscopy for H. pylori culture and histology. All of them received a UBT in which the duplicate baseline, 10 min, and 15 min breath samples after ingestion of 50 mg (13)C-urea were collected to analyse the excess (13)CO(2)/(12)CO(2) ratio (ECR) by IRMS (ABCA, Europa Scientific, UK) and INIS (UBiT-IR200, Photal Otsuka Electronics, Japan), respectively.

RESULTS

Of the 177 patients, 84 were infected and 93 were uninfected with H. pylori. A close correlation of ECR was found between IRMS and INIS (r=0.9829 at 10 min; r=0.9918 at 15 min, P < 0.0001). Analysing the 15-min samples, UBT by both IRMS and INIS achieved the same sensitivity (96. 4%) and specificity (98.9%).

CONCLUSIONS

INIS is as effective as IRMS for UBT, and can use a lower dose of (13)C-urea. This can provide an economic UBT, using the lower-priced INIS and a low dose of (13)C-urea.

Delayed administration of the K+ channel activator cromakalim attenuates cerebral vasospasm after experimental subarachnoid hemorrhage

BACKGROUND

Delayed cerebral vasospasm remains an unpredictable and inadequately treated complication of aneurysmal subarachnoid hemorrhage (SAH). Recent evidence indicates that the potassium channel activator cromakalim is capable of limiting cerebral vasospasm in rabbits when administered immediately after experimental SAH (i.e. before spastic constriction has been initiated). However, the ultimate clinical value of cromakalim for treating vasospasm will depend in part on its effectiveness when administered after SAH-induced constriction has already been initiated. The present study examined the effects of cromakalim on vasospasm when treatment was initiated after SAH-induced constriction was underway.

METHODS

New Zealand white rabbits were subjected to experimental SAH by injecting autologous blood into the cisterna magna. Cromakalim (0.03, 0.1 or 0.3 mg/kg) or vehicle was injected intravenously at 8 hour intervals beginning 24 hours post-SAH. Animals were killed by perfusion fixation 48 hours after SAH. Basilar arteries were removed and sectioned, and cross-sectional area was measured.

FINDINGS

The average cross sectional areas of basilar arteries were reduced by 64% and 68% in the SAH-only and SAH + vehicle groups, respectively. Treatment with cromakalim dose-dependently attenuated SAH-induced constriction. The groups treated with 0.03, 0. 1, and 0.3 mg/kg cromakalim exhibited average decreases in cross-sectional area of 57%, 42%, and 19%, respectively.

INTERPRETATION

These findings indicate that cromakalim dose-dependently attenuates cerebral vasospasm when administered 24 hours after experimental SAH in the rabbit. The results suggest K(ATP) channel activators, such as cromakalim. could be of benefit for reversing cerebral vasospasm after aneurysmal SAH.

SAR studies of 2-o-substituted-benzoyl- and 2-alkanoyl-cyclohexane-1,3-diones as inhibitors of 4-hydroxyphenylpyruvate dioxygenase

Inhibition studies of 4-hydroxyphenylpyruvate dioxygenase (HPPD) with various synthesized 2-o-substituted-benzoyl- and 2-alkanoyl-cyclohexane-1,3-diones suggest that the presence of a strongly electronegative group at the ortho position and the conformation of the benzene ring moiety on the benzoylcyclohexane-1,3-dione inhibitors are crucial for potent HPPD inhibition.

Cutaneous blood flow and adrenoceptor response increase in segmental-type vitiligo lesions

It has been proposed that two types of vitiligo exist from the physiological and clinical points of view. Nonsegmental-type vitiligo is associated with autoimmune diseases while segmental-type vitiligo results from the dysfunction of sympathetic nerves in the affected area. Using laser Doppler flowmetry and iontophoresis for cutaneous microcirculatory assessments, we evaluated these two types of vitiligo in regard to their physiological changes. Ten patients with facial stable stage segmental-type vitiligo and ten stable nonsegmental-type vitiligo patients were selected for this study. Our results revealed that a nearly threefold increase in cutaneous blood flow was noticed in segmental-type vitiligo as compared to contralateral normal skin. In contrast, a 1.4-1.5 times difference was found among nonsegmental-type vitiligo, lesion side clinically normal skin and contralateral normal skin. There was a significant increase in cutaneous alpha- and beta-adrenoceptor response in segmental-type vitiligo lesions. However, no change in plasma catecholamines or adrenoceptor densities on blood cells was noticed. Our findings suggest that a dysfunction of the sympathetic nerves exists in the affected skin and plays a role in the pathogenesis of segmental-type vitiligo.

Influence of aortopulmonary rotation on the anomalous coronary artery pattern in tetralogy of fallot

Three main patterns of aortic sinus rotation were defined on 517 lateral angiograms of tetralogy of Fallot with 14 cases of anomalous coronary artery pattern occurring only in patients with a right anterior or right lateral aorta. The significant dependence of coronary artery types on the aortic sinus pattern made it possible to predict the predisposing coronary artery pattern in tetralogy of Fallot based on the aortic sinus pattern.

Midterm results of aortic valve reconstruction for congenital aortic stenosis with or without regurgitation

Aortic valve is often replaced if valvular stenosis fails to be balloon dilated. Aortic valve reconstruction was performed on 4 patients from August 1993 to 1999. Their ages ranged from 1 month to 15 years (mean 8.3 years). Unicuspid aortic valve was present in three of them and bicuspid in the other one. Two patients were associated with a patent arterial duct, one aortic regurgitation, and one pulmonary stenosis. Commissurotomy was done in three of them to transform the aortic valve into tricuspid except one, in whom bicuspid valve was preserved. In one case with unicuspid aortic valve, a piece of tanned autologous pericardium was used to augment one myxomatous and retracted leaflet. The sinus of Valsalva was molded together with a bulging shape of its aortic leaflet. All four were weaned from cardiopulmonary bypass smoothly. Transesophageal echocardiography in one case prompted rebypass to decrease the degree of regurgitation from moderate to mild by further shaping of the leaflet and sinus of Valsalva. In one patient chylopericardium was complicated and subsided in 5 days after conservative treatment. All patients were doing well on follow up at 56.8 +/- 34.4 months after surgery, with trivial to mild systolic pressure gradient (20 +/- 26 mmHg; preoperatively: 88 +/- 36 mmHg) and mild regurgitation. Aortic valve reconstruction is feasible in the setting of congenital aortic stenosis in our limited experience; repair instead of replacement is recommended even when regurgitation is present.

Epstein-Barr virus-encoded latent membrane protein 1 co-expresses with epidermal growth factor receptor in nasopharyngeal carcinoma

Latent membrane protein 1 (LMP-1) is the only Epstein-Barr virus (EBV)-encoded oncogenic protein that has been detected in nasopharyngeal carcinoma (NPC), a cancer that is closely associated with EBV. Previous in-vitro studies have demonstrated that LMP-1 can upregulate epidermal growth factor receptor (EGFR) in epithelial cells. It was not established whether this cellular effect exists in NPC. To assess the association between LMP-1 and EGFR in NPC tissues, 60 NPC specimens were examined by immunohistochemistry using anti-LMP-1 antibody (CS 1-4) and anti-EGFR antibodies (EGFR 1, EGFR 1005). The results revealed that 41 (68.3%) specimens were immunopositive for LMP-1 and 44 (73.3%) specimens over-expressed EGFR. Morphologically, the expressions of LMP-1 and EGFR were homogeneously distributed in the tumor nests. In addition, the correlation between LMP-1 and EGFR was statistically significant (P<0.001, chi2 test, d.f. = 1). To elucidate further the correlation between LMP-1 and EGFR in vivo and in situ, an indirect dual immunofluorescence assay was conducted, using secondary antibodies conjugated with fluorescein isothiocyanate (FITC) or indocarbocyanine (Cy3). The results disclosed an intimate co-expression of LMP-1 and EGFR. In summary, the data indicate that over-expression of EGFR is a common phenomenon in NPC, and that EGFR is co-expressed with LMP-1 in NPC. Thus, EBV may play a role in the tumorigenesis of NPC through the effects of LMP-1 and EGFR.

Intractable oesophageal variceal bleeding caused by splenic arteriovenous fistula: treatment by transcatheter arterial embolization

We describe a rare case of splenic arteriovenous fistula and venous aneurysm which developed after splenectomy in a 40-year-old woman who presented with epigastralgia, watery diarrhoea, repeated haematemesis and melaena caused by hyperkinetic status of the portal system and bleeding of oesophageal varices. It was diagnosed by computed tomography and angiography, and obliterated with giant Gianturco steel coils.

Primary chiasmal sarcoid granuloma: MRI

We report MRI findings of a pathologically proven primary sarcoid granuloma of chiasmal origin that mimicked an optic pathway glioma

Defective IL-2 receptor expression in lymphocytes of patients with arsenic-induced Bowen's disease

The immune function of peripheral mononuclear cells (MNC) in patients with endemic arsenic-induced Bowen's disease (BD) was investigated. Many cytokines and immune-related factors were determined in the present study. Interleukin-1beta and TNF-alpha production was used as an indicator of monocyte/macrophage function. II-2 and sIL-2R production was used as an indicator of lymphocyte activation. The release of sCD4 and sCD8 was used as an indicator of activation of respective T-cell subpopulations. Production of IFN-gamma and IL-2 reflected the cellular effector function of helper T-cells type 1. In vivo cell-mediated immunity was also assessed by estimation of the percentage of T-cells in peripheral blood MNC and the nonspecific delayed-type hypersensitivity (DTH) response to 2,4-dinitrochlorobenzene (DNCB). Both assays revealed depressed cell-mediated immunity in BD. Compared with healthy controls, spontaneous and PHA-induced IFN-gamma and TNF-alpha production was significantly decreased in BD whereas spontaneous release of IL-2, sCD4 and sCD8 was significantly increased. Although PHA stimulation increased IL-2 release, the expression of IL-2R alpha and beta chains and the release of sIL-2R were not proportionately increased in BD. In addition, IL-2-mediated [3H]-thymidine incorporation by MNC in patients with BD was significantly decreased. These findings suggest that the defective cell-mediated immune function in BD is due to impairment of membrane IL-2R expression in lymphocytes after stimulation.

Does famotidine have similar efficacy to misoprostol in the treatment of non-steroidal anti-inflammatory drug-induced gastropathy?

The study aimed to evaluate the efficacy of famotidine, an H2 receptor blocker, and misoprostol, a prostaglandin E analogue, in the treatment of non-steroidal anti-inflammatory drug-induced (NSAID) gastropathy in arthritic patients. A total of 128 patients receiving piroxicam, sulindac, indomethacin, naproxen, tolmetin and aspirin were enrolled in the study. Gastroscopic examination was performed at the beginning and after eight weeks of randomised famotidine or misoprostol treatment. A standard scoring method for gastroscopic finding was applied. Forty-four patients with scores 1-3 were classified as group A; while the other 84 with score 4 (ulcer) were placed in group B. In group A, 26 received famotidine and 18 misoprostol. In group B, 36 received famotidine and 48 misoprostol. Biopsy specimens taken from the rim of the ulcer with adjacent normal mucosa were coded and tested for Helicobacter pylori. In group A, all but two patients taking famotidine recovered from NSAID gastropathy, and there was no statistical significance between the two drugs. In group B, all but four patients receiving famotidine improved and there was no statistical significance between the two subgroups for complete healing rate. The prevalence of H. pylori was 36.9%, lower than that in the general population. It was concluded that famotidine and misoprostol have similar efficacy in the treatment of NSAID gastropathy.

Effervescent gallbladder: sonographic findings in emphysematous cholecystitis

We report a case of emphysematous cholecystitis with the sonographic appearance of an "effervescent gallbladder"--a large amount of gas bubbles rising like bubbles in a glass of champagne from the dependent part of the gallbladder and floating to the nondependent part. The etiology of this finding was acute obstruction of the distal common bile duct by a stone and purulent cholangitis. Short-term follow-up sonography is important to confirm the diagnosis of cholecystitis.

Research on pelvic angle variation when using a pelvic support

A pelvic support consisting of a forward sloping wedge of foam has been tested as an addition to conventional office seating for VDT work. In experiment 1 a questionnaire investigation was carried out on the impressions of 10 male and 10 female subjects who sat using pelvic supports. A general result from the questionnaire was that the waist and pelvis were felt to be stable and the evaluation was more positive with the support than without. In experiment 2, pelvis and chest inclinations were measured during sitting with and without the pelvic support. Over a long work period, significant differences were not observed. In both cases, subjects were able to move freely and there were no significant changes in posture. In experiment 3, pelvis and chest inclinations were measured in conditions of no pelvic support and with supports of 10, 20 and 30 degrees. The experiment demonstrated that a support angle of 10 degrees was stable and comfortable. In this research, it was found that the change of inclination of the pelvis can be measured continuously using an angle of inclination sensor. Imposing a forward slope of 4 to 10 degrees on the seat pan surface using the pelvic support had a positive effect, while angles of 20 and 30 degrees had a negative effect.