Gait characteristics of patients with sciatica / 医用生物力学

Objective To analyze and summarize the gait characteristics of patients with sciatica, so as to assist with diagnosis and evaluation for such patients in clinic. Methods Forty-three patients with lumbar disc herniation accompanied by siatica were fitted with portable gait analyzer, and required to walk at the self-selected comfortable speed for a distance of 120 m. Forty-three healthy subjects with matched age, gender and body mass index (BMI) were recruited as control. The gait data including 7 spatial-temporal parameters (single-support duration, double-support duration, ratio of single-support duration to double-support duration, duration of gait cycle, step speed, step frequency, step length) and 4 acceleration parameters (pulling acceleration, swing power, ground impact, foot fall) were collected to compare the gait differences between patients and healthy subjects, as well as between affected and healthy limbs of patients. Results The single-support duration, ratio of single-support duration to double-support duration, step speed, step frequency, step length and four acceleration parameters of patients with sciatica were obviously smaller than those of healthy subjects, while the double-support duration of patients with sciatica was increased. The affected limb of patients with sciatica showed a significant decrease in single-support duration, step frequency and all four acceleration parameters but increase in step length as compared to their healthy limbs. Conclusions Patients with sciatica have significant gait abnormalities due to their affected limbs, which influence their walking ability. Portable gait analyzer can be used for objectively characterizing the walking abnormalities of patients, so as to provide additional information for the clinical diagnosis and evaluation.

Diagnostic features of pathological fractures located in extremities caused by bone tumor or tumor like lesion / 中华骨科杂志

ObjectiveTo explore the clinical characteristics of pathological fracture in extremities caused by bone tumors or tumor-like lesions. MethodsFrom August 2002 to December 2010, 139 patients with pathological fractures were entered in the study, including 79 males and 60 females with an average age of 31.1 years. Fractures included tumor-like lesion in 55 cases, benign tumor in 13, giant cell tumor (GCT)in 7, primary malignant tumors in 28, and metastatic tumors in 36. Forces induced to fractures were classified into four grades: spontaneous fracture, functional activity, minor injury, severe injury. Age, fracture location, histological results, fractures forces, prodromes, and misdiagnosis were all observed. Chi-square test were use to compare forces and prodromes within different tumors. ResultsThe highest morbidity rate is 32.4％(45/139) which lies in 11-20 years old. The cites of fractures including femurs in 71 cases, humerus in 36, tibia in 15, fingers in 7, radiuses in 4, fibula in 3, ulnas in 2, and metatarsus in 1. Fracture forces include spontaneous fractures in 29 cases, functional activity in 42, minor injuries in 65, and traumatic injuries in 3. Sixty-seven patients(48.2％) had local prodromes. The prodromes of both malignant tumors and metastatic tumors were more than benign tumors. Twenty cases experienced misdiagnosis with average delay time of 12 weeks. ConclusionMinor injury forces and local prodromes are clinical key features of pathological fractures. Both of them are key points of avoiding misdiagnosis.

Characteristic analysis of E protein genes of new strains of tick-borne encephalitis virus isolated from China / 病毒学报

In order to determine the characteristics and genotypes of E protein genes of tick-borne encephalitis (TBE) virus strains DXAL-5, 12,13,16,18, 21 isolated from Ixodes persulcatus in the Northeast of China, cDNA synthesis of E protein genes of the six DXAL strains was performed using RT-PCR, and the E protein genes were cloned and sequenced. The results showed that the nucleotide sequence of E protein gene of the six DXAL strains was 1488 bp in length respectively and the length of predicted protein was 496 aa respectively. Sequence comparison of E protein genes among the six DXAL strains and the reference TBE virus strains showed that the six DXAL strains were more homologous to Far Eastern subtype strains than to Siberian subtype strains or European subtype strains. And the majority of subtype-determining amino acid sites of the six DXAL strains belonged to TBE virus Far Eastern subtype. Phylogenetic analysis of protein E showed that the six DXAL strains were all within the clade containing Far Eastern subtype strains. The new strains had higher identities and closer phylogenetic relationships with Senzhang strain, so we speculate that this vaccine strain still have good protection against the new TBE virus isolates. In the A, B and C antigenic domains of protein E, the six DXAL strains had different degrees of amino acid changes. These mutations were likely to affect the function of E protein.

Association between sequence variation of Env, Gag genes from the same source and HIV-1 disease progression and host genetic polymorphism / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand the relationship between the HIV-1 viral sequence variation and host factors associated with HIV-1 disease progression.</p><p><b>METHODS</b>Env and gag fragments of HIV-1 were amplified with PCR, cloned and sequenced. Bioinformatics was employed to find the genetic variation, N-linked glycosylation, hypermutation etc. Host gene polymorphism was analysed by using restricted fragment length polymorphism (RFLP).</p><p><b>RESULTS</b>Significant difference was found in genetic divergence between Env PCR dominant and clonal sequences (0.1 and 0.06, respectively) in non-treated group, but no significant difference was found in the HAART treated group. V3 GPGQ accounted for the most part in both treated and nontreated groups, rare V3 loop such as GPGH, GQGR and GLGR was found in treated group, V3 substitutions of I/V (position 12) and Y/H (position 21) was associated with the relatively rapid progression (RRP). Glycosylation was significantly higher in RRP than in TP for Env region, GA substitution in RRP was also significantly higher than that in TP group. SDF1-3primeA and CCR2 V64I gene frequency was higher in TP than in RRP, but the difference was not significant.</p><p><b>CONCLUSION</b>Disease progression was associated with V3 AA change, glycosylation and GA substitution in env gene. SDF1-3primeA, CCR2 V64I and CX3CR1 V249I/M280T was not associated with disease progression significantly.</p>