The fliL gene significantly affects the motility and sporulation abilities of Clostridioides difficile / 生物工程学报

Flagella are the main motility structure of Clostridioides difficile that affects the adhesion, colonization, and virulence of C. difficile in the human gastrointestinal tract. The FliL protein is a single transmembrane protein bound to the flagellar matrix. This study aimed to investigate the effect of the FliL encoding gene flagellar basal body-associated FliL family protein (fliL) on the phenotype of C. difficile. The fliL gene deletion mutant (ΔfliL) and its corresponding complementary strains (: : fliL) were constructed using allele-coupled exchange (ACE) and the standard molecular clone method. The differences in physiological properties such as growth profile, antibiotic sensitivity, pH resistance, motility, and spore production ability between the mutant and wild-type strains (CD630) were investigated. The ΔfliL mutant and the : : fliL complementary strain were successfully constructed. After comparing the phenotypes of strains CD630, ΔfliL, and : : fliL, the results showed that the growth rate and maximum biomass of ΔfliL mutant decreased than that of CD630. The ΔfliL mutant showed increased sensitivity to amoxicillin, ampicillin, and norfloxacin. Its sensitivity to kanamycin and tetracycline antibiotics decreased, and the antibiotic sensitivity partially returned to the level of CD630 strain in the : : fliL strain. Moreover, the motility was significantly reduced in the ΔfliL mutant. Interestingly, the motility of the : : fliL strain significantly increased even when compared to that of the CD630 strain. Furthermore, the pH tolerance of the ΔfliL mutant significantly increased or decreased at pH 5 or 9, respectively. Finally, the sporulation ability of ΔfliL mutant reduced considerably compared to the CD630 strain and recovered in the : : fliL strain. We conclude that the deletion of the fliL gene significantly reduced the swimming motility of C. difficile, suggesting that the fliL gene is essential for the motility of C. difficile. The fliL gene deletion significantly reduced spore production, cell growth rate, tolerance to different antibiotics, acidity, and alkalinity environments of C. difficile. These physiological characteristics are closely related to the survival advantage in the host intestine, which is correlated with its pathogenicity. Thus, we suggested that the function of the fliL gene is closely related to its motility, colonization, environmental tolerance, and spore production ability, which consequently affects the pathogenicity of C. difficile.

Group Ⅱ introns and the application in biotechnology: a review / 生物工程学报

Group Ⅱ introns are self-splicing ribozymes, which insert directly into target sites in DNA with high frequency through "retrohoming". They specifically and efficiently recognize and splice DNA target sites, endowing themselves with great potential in genetic engineering. This paper reviewed the gene targeting principle of group Ⅱ introns and the application in microbial genetic modification, and then analyzed the limitations of them in multi-functional gene editing and eukaryotes based on the "retrohoming" characteristics and the dependence on high Mg2+ concentration. Finally, we dissected the potential of group Ⅱ introns in the development of novel gene editing tools based on our previous research outcome and the structural characteristics of the introns, hoping to provide a reference for the application of group Ⅱ introns in biotechnology.

The effect of virtual reality prism adaptation on visuospatial neglect in stroke patients / 中华物理医学与康复杂志

Objective To investigate the effects of virtual reality prism adaptation on visuospatial neglect in stroke patients.Methods Thirty stroke patients with visuospatial neglect were studied.The subjects were divided into atreatment group and a control group.The subjects in the treatment group were treated with virtual reality prism adaptation and routine rehabilitation interventions for 2 weeks,while those in the control group were treated with routine rehabilitation interventions only.All the patients performed a battery of spatial attention tests including line bisection,letter cancellation,clock drawing and the Attention Network Test at the beginning and after 2 weeks of treatment.Results The virtual reality prism adaptation training had significant positive effects on all the measures of visuospatial neglect.Pair-wise comparisons confirmed significant differences between the treatment and control groups after 2 weeks of treatment with regard to all of the measures.Conclusions Virtual reality prism adaptation treatzment combined with routine rehabilitation can be more effective than conventional measures alone in improving the visuospatial performance of stroke survivors.

The posterior parietal cortex in visuospatial attention:study with continuous theta burst stimulation / 中华物理医学与康复杂志

Objective To seek more direct evidence of the role of the posterior parietal cortex (PPC) in controlling visuospatial attention.Methods Forty healthy subjects took the Attention Network Test following continuous theta burst stimulation (cTBS) applied over the left or right PPC or sham stimulation.The Attention Network Test measures the alerting,orienting and executive control components of visual attention separately.Results Subjects responded to spatial cues significantly slower after cTBS.Alerting and orienting showed deficits after cTBS over the right PPC.cTBS over the left PPC resulted in significant improvements in alerting,but not in the orienting.Furthermore,there were significant differences in the alerting and orienting indices between cTBS over the left and right PPC,but not in the executive control index.Conclusions The results suggest that the right PPC is associated with spatial orienting and the alerting function.The findings supported the theory of inter-hemispheric competition for visuospatial attention.Visuospatial attention bias might be selectively modulated through cTBS.

The effect of transcranial electrical stimulation on functional recovery and the expression of microtubule-associated protein-2 and growth-associated protein-43 after cerebral focal ischemia / 中华物理医学与康复杂志

Objective To assess the influence of transcranial electric stimulation (TES) on the recovery of motor function after cerebral focal ischemia and reperfusion and to explore the mechanisms in terms of neural plasticity.Methods An acute focal ischemia-reperfusion model was established by transient occlusion of the right middle cerebral artery (MCAO).Seventy-two male Sprague-Dawley rats were randomly divided into a TES group,a model group,a sham-operation group and a normal group.The TES group was given TES 24 h after MCAO;the model group received the operation without any treatment.Forelimb placing (FPT) and beam walking (BWT) were mea-sured at the 3rd,7th,14th and 28th day after reperfusion.Microtubule-associated protein-2 (MAP-2) and growth-associated protein-43 (GAP-43) and grey levels of reaction products in the peri-infarct region were examined by immunohistochemical techniques.Results The TES group rats had markedly better FPT and BWT performance at the 7th,14th and 28th day after MCAO,compared with the model group.Expression of MAP-2 had increased significantly more at the 14th and 28th day in the peri-infarct region in the TES group compared with the model group.Expression of GAP-43 was significantly elevated in the peri-infarct region in the TES group compared with the model group at all time points.Conclusions TES can improve motor function and neural plasticity following cerebral ischemia and reperfusion damage.The functional enhancement may be partly due to up-regulation of the expression of GAP-43 and MAP-2 in the peri-infarct region.

Transcranial Electrical Stimulation and Rehabilitation Training on Functional Recovery and Growth Associated Protein-43 Expression in Rats after Focal Ischemic Infarction / 中国康复理论与实践

@#ObjectiveTo assess how transcranial electrical stimulation (TES) concurrent with rehabilitation training influences brain plasticity and behavioral functional performance in rats following a focal ischemic infarction.MethodsAfter an acute focal ischemic infarction by transient occlusion of right middle cerebral artery (MCAO), the electric stimulation concurrent with rehabilitation group was given TES, balancing and rotating and walking exercise everyday; the rehabilitation group was given only balancing and rotating and walking exercise everyday; the control group received no treatment. Growth associated protein 43(GAP-43) was examined by immunohistochemical techniques, and density of reaction product and forelimb placing test (FPT) were measured on the 3rd, 7th, 14th and 28th day after infarction respectively.ResultsThe electrical stimulation concurrent with rehabilitation group provided marked improvement in FPT on the 7th, 14th and 28th day compared with the rehabilitation group and the control group (P<0.01～0.05). The GAP-43 demonstrated statistically significant increase on the 3rd, 7th, and 14th day in the peri-infarct region in the electrical stimulation concurrent with rehabilitation group compared with other two groups(P<<0.01～0.05).ConclusionThe efficacy of transcranial electrical stimulation combining with rehabilitation training can improve functional outcome and neuronal plasticity following ischemic cerebral damage. The mechanism may be partly due to the upregulation of the expression of GAP-43 in the peri-infarct region. Meanwhile, the efficacy is superior to rehabilitation training only.

A study of body image,prosthesis satisfaction and quality of life of the amputees from 5·12 Wenchuan earthquake / 中华物理医学与康复杂志

Objective To explore body image(BI),prosthesis satisfaction and quality of life(QOL)of amputees from Wenchuan earthquake and the relationship among them to provide evidence for the intervention.Methods A total of 21 amputees accepted a survey regarding QOL,BI,and satisfaction with prosthesis.The scale of SF-36 was used to assess QOL.Amputees Bodily Image Scale(ABIS)was;used to assess BI.A self-design questionnaire wag used to evaluate the prosthesis satisfaction of amputees.Results The scores of SF-36,ABIS,and prosthesis satisfaction wag 41.90 ±15.00,64.58 ±10.60,and 59.52±11.06,respectively.The ABIS scores in women(65.07 ±12.10)were hisher than that in men(63.20 ±5.0)(P＜0.05).There was a positive correlation between score of QOL and prosthesis satisfaction,but a negative correlation between QOL and BI.The negative correlations were also observed between BI and Vitality,BI and mental health.Prosthesis satisfaction had positive correla tions with education level.QOL and mental health.Conclusion The body image disturbance(BID)and dissatis faction with prosthesis may cause negative influences on the amputees'quality of life.Relevant intervention should be provided of amputees handling their prostheses and body images correctly and raising QOL.

Interactions of Helicobacter pylori and its L-forms with surfactant protein D / 基础医学与临床

Objective To explore the affinify of combination of Helicobacter pylori (Hp) and its L-form with surfactant protein D(SP-D),and to find function of SP-D in Hp infection and immunity. Methods SP-D was extracted from the lung of rats by Tris-HCl-EDTA and maltose-agarose affinity column. The combination of Hp and SP-D was detected by slide and tube agglutination tests,and the agglutination inhibition with SP-D immune serum was carried out. The L-form of Hp was induced by Ceftriaxon sodrum and identified by PCR and sequencing of the 16S rDNA fragment.The combination of SP-D and the L-form was tested by slide agglutination test. Results Agglutination of Hp NCTC11637 and SP-D was observed on slide,but NCTC11639,SS1 and the L-form failed to agglutinate. Agglutination was found 45 minutes after reaction and was inhibited by SP-D immune sera. Conclusion The ability of combination with SP-D was different between strains of Hp.The combination could be weakened or vanished when Hp lost the cell wall.

Experimental study on the penetrability of trypan blue to the rat prostate / 中华男科学杂志

<p><b>OBJECTIVE</b>To understand the penetrability of trypan blue to the normal prostate as well as to the inflammatory prostate and the prostate with benign hyperplasia in rats.</p><p><b>METHODS</b>Sixty SD male rats were randomized into 4 groups: NP (normal prostate) group (n = 15), BP (bacterial prostatitis) group (n = 15), BPH (benign prostatic hyperplasia) group (n = 15), and BPH-BP (benign prostatic hyperplasia with bacterial prostatitis) group (n = 15). Five rats were taken from each group as non-staining controls (NC, n = 5 x 4) and the other 10 were injected by tail intravenation with 1% trypan blue and then the prostates were isolated from the rats killed by anaesthesia after 2 hours. The color of the prostates and other tissues of the animals were observed and the contents of the trypan blue in the tissues of the prostates were determined separately by colorimetry.</p><p><b>RESULTS</b>Apart from the tissues of brains and spinal cord the surface and the inner tissues of the prostates with NP, BP, BPH and BPH-BP from the rats injected with the dye were also dyed blue similar to that of the muscles, livers, intestines and others. The content of the trypan blue in the tissues of the prostates with NP, BP and BPH-BP was obviously higher than those with NP and BPH.</p><p><b>CONCLUSION</b>The penetrability of trypan blue with properties of ionization and larger molecular weight is high in either the normal prostate or the prostate with BP, BPH and BPH-BP, and much higher in inflammatory prostate than in the normal prostate and the prostate with BPH.</p>