EFFECT OF BACKPACK ON SELECTED GAIT PARAMETERS OF PRIMARY SCHOOL CHilDREN

The purpose of this study was to compare the effects of a backpack load of 15% body weight (BW) on selected gait parameters of primary school children. Ten participants were recruited from primary school (age: 10.3 ± 0.48 yrs; hI: 141.3 ± 0 .41 cm; mass: 38.1 ± 6.1 kg). A JVC 9800 (60 hz) video camera synchronized with an AMTI force plate (1200 Hz) were used to collect data. A repeated measure t-test (p < 0.05) was used for group comparisons. The backpack load did not affect either the proportionate time of the stance phase, swing phase, or the magnitude of selected vertical and anterioposterior ground reaction force parameters. However, the 15% backpack load did cause a significant increase in proportionate double leg support time

Sinus automaticity and sinoatrial conduction in severe symptomatic sick sinus syndrome

AbstractElectrophysiologic studies with recordings of sinus node electrograms were performed in 38 patients with severe symptomatic sick sinus syndrome. Thirty-two of the 38 patients had episodic tachyarrhythmias and 17 presented with syncope. The clinically documented sinus or atrial pause was 5.6 ± 2.8 s (mean ± SD).Patients were divided into three groups according to electrophysiologic findings. Group I consisted of nine patients with complete sinoatrial block. Sinus node electrograms were recorded during the episodes of long pauses. Seven patients had unidirectional exit block, with the atrial impulse being capable of retrograde penetration to the sinus node causing suppression of sinus automaticity; two had bidirectional sinoatrial block.Group II consisted of 22 patients with either 1:1 sinoatrial conduction (group IIa = 13 patients) or second degree sinoatrial exit block (group IIb = 9 patients) during spontaneous sinus rhythm. Sinoatrial exit block, ranging from 1 to >14 sinus beats, was observed during postpacing pauses that ranged from 1,650 to 37,000 ms (mean 7,286 ± 6,989). The maximal sinus node recovery time ranged from 770 to 5,580 ms (mean 3,004 ± 1,686) and was normal in 5 patients and prolonged in 17.Group III consisted of seven patient with no recordable sinus node electrogram, reflecting either a technical failure or a quiescence of sinus activity. The sinus node recovery time in these seven patients ranged from 1,190 to 4,260 ms (mean 2,949 ± 1, 121).Thus, abnormalities in both sinus node automaticity and sinoatrial conduction are responsible for the long sinus or atrial pauses in the sick sinus syndrome. However, complete sinoatrial exit block can occur and cause severe bradycardia with escape rhythm; repetitive sinoatrial exit block plays a major role in producing posttachycardia pauses

Molecular events associated with epithelial to mesenchymal transition of nasopharyngeal carcinoma cells in the absence of Epstein-Barr virus genome

Epithelial-mesenchymal transition (EMT) is an important process in tumor metastasis. The EMT-related events associated with metastasis of NPC in the absence of EBV have not been elucidated. We established an EBV-negative NPC cell line from a bone marrow biopsy of an NPC patient. Using a Matrigel system we isolated an invasive and non-invasive sublines, designated NPC-BM29 and NPC-BM00. NPC-BM29 acquired an invasive-like phenotype characterized by EMT, marked by down-regulation of E-cadherin and β-catenin with concomitant increased expression of Ets1. NPC-BM29 cells expressed ≥ 10-fold higher of MMP-9 than NPC-BM00 cells. NPC-BM29 cells grew better in 2% serum than NPC-BM00 cells, with a population doubling-time of 26.8 h and 30.7 h, respectively. A marked reduction in colony-formation ability of NPC-BM00 cells compared to NPC-BM29 was observed. Wound-healing assay revealed that NPC-BM29 cells displayed higher motility than NPC-BM00 and the motility was further enhanced by cell treatment with TPA, a PKC activator. Cell surface markers and tumor-associated molecules, AE3, MAK6 and sialyl-Tn, were up-regulated in NPC-BM29 cells, whereas the expression of HLA-DR and CD54 was significantly increased in NPC-BM00 cells. NPC-BM29 consistently released higher levels of IL-8 and IL-10 than NPC-BM00, with low levels of IL-1α expression in both cell lines. Higher level of VEGF production was detected in NPC-BM00 than NPC-BM29 cells. These data show that EBV is not required for exhibiting multiple metastatic phenotypes associated with EMT. More studies that target right molecules/signalings associated with the EMT may offer new therapeutic intervention options for NPC invasion and metastasis

Solanum lyratum

We investigated the molecular mechanisms of cell cycle arrest and apoptotic death induced by Solanum lyratum extracts (SLE) or diosgenin in WEHI-3 murine leukemia cells in vitro and antitumor activity in vivo. Diosgenin is one of the components of SLE. Our study showed that SLE and diosgenin decreased the viable WEHI-3 cells and induced G0/G1 phase arrest and apoptosis in concentration- or time-dependent manners. Both reagents increased the levels of ROS production and decreased the mitochondrial membrane potential (ΔΨm). SLE- and diosgenin-triggered apoptosis is mediated through modulating the extrinsic and intrinsic signaling pathways. Intriguingly, the p53 inhibitor (pifithrin-α), anti-Fas ligand (FasL) mAb, and specific inhibitors of caspase-8 (z-IETD-fmk), caspase-9 (z-LEHD-fmk), and caspase-3 (z-DEVD-fmk) blocked SLE- and diosgenin-reduced cell viability of WEHI-3 cells. The in vivo study demonstrated that SLE has marked antitumor efficacy against tumors in the WEHI-3 cell allograft model. In conclusion, SLE- and diosgenin-induced G0/G1 phase arrest and triggered extrinsic and intrinsic apoptotic pathways via p53 activation in WEHI-3 cells. SLE also exhibited antitumor activity in vivo. Our findings showed that SLE may be potentially efficacious in the treatment of leukemia in the future

Molecular signature of clinical severity in recovering patients with severe acute respiratory syndrome coronavirus (SARS-CoV)

BACKGROUND: Severe acute respiratory syndrome (SARS), a recent epidemic human disease, is caused by a novel coronavirus (SARS-CoV). First reported in Asia, SARS quickly spread worldwide through international travelling. As of July 2003, the World Health Organization reported a total of 8,437 people afflicted with SARS with a 9.6% mortality rate. Although immunopathological damages may account for the severity of respiratory distress, little is known about how the genome-wide gene expression of the host changes under the attack of SARS-CoV. RESULTS: Based on changes in gene expression of peripheral blood, we identified 52 signature genes that accurately discriminated acute SARS patients from non-SARS controls. While a general suppression of gene expression predominated in SARS-infected blood, several genes including those involved in innate immunity, such as defensins and eosinophil-derived neurotoxin, were upregulated. Instead of employing clustering methods, we ranked the severity of recovering SARS patients by generalized associate plots (GAP) according to the expression profiles of 52 signature genes. Through this method, we discovered a smooth transition pattern of severity from normal controls to acute SARS patients. The rank of SARS severity was significantly correlated with the recovery period (in days) and with the clinical pulmonary infection score. CONCLUSION: The use of the GAP approach has proved useful in analyzing the complexity and continuity of biological systems. The severity rank derived from the global expression profile of significantly regulated genes in patients may be useful for further elucidating the pathophysiology of their disease

Diversity of the association of serum levels and genetic variants of MHC class I polypeptide-related chain A with liver fibrosis in chronic hepatitis C

Background/Aims Genetic variants of MHC class I polypeptide-related chain A (MICA) at rs2596542 have been associated with hepatocellular carcinoma. The linkage between serum MICA (sMICA) and liver fibrosis in chronic hepatitis C is elusive. Results: Linear regression analysis revealed that sMICA were independently correlated to α-fetoprotein (β: 0.149; 95% confidence interval [CI]: 0.001, 0.003; P = 0.007)and MICA rs2596542 GG genotype (β: 0.209; 95% CI: 0.153, 0.483; P 50 pg/mL provided a positive predictive value of 72 % in predicting advanced liver fibrosis (F3-4) and of 90% in significant fibrosis (> F2) in MICA rs2596542 A allele carriers. Materials and Methods Serum level and single nucleotide polymorphism at rs2596542 of MICA were tested for the association with liver fibrosis in 319 biopsy proven chronic hepatitis C patients. Conclusions: Levels of sMICA were highly correlated to liver disease severity in chronic hepatitis C patients who carried the MICA rs738409 A allele. Patients possessing the genetic predisposition had a higher likelihood of progressed liver fibrosis if they expressed higher sMICA levels