Gait Disorders and Magnetic Resonance Imaging Characteristics in Older Adults with Cerebral Small Vessel Disease.

BACKGROUND: This study aims to explore the features of gait disorders with cerebral small vessel disease (CSVD), and results from magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) were analyzed. METHODS: The 139 patients with CSVD were divided into two groups by the Tinetti scale scores: the gait disorder (GD) group with a score <24 (63 patients) and the normal gait (GN) group with a score ≥24 (76 patients). A series of scales and 3.0T MRI with DTI were used to analyze the correlation between the abnormal gaits and imaging findings. RESULTS: The differences in the Barthel Index, Unified Parkinson's Disease Rating Scale part III, and Montreal Cognitive Assessment (MoCA) scores between the two groups were significant (p < 0.05), and there were significant correlations between MoCA and total gait scores (r = 0.201, p = 0.002). The GD group had a more degraded gait score, widened gait base, and degraded gait length than the GN group (p < 0.05). There were significant differences between the two groups (p < 0.05) in white matter (WM) hyperintensities (WMH) of the Fazekas scale grade 2-3 and lacunes. The GD group had a greater total MRI burden than the GN group (p < 0.05). In DTI parameters, the GD group had lower fractional anisotropy (FA) and higher mean diffusion (MD) values in WM tracts in many areas around the ventricles (family-wise error corrected, p < 0.05). Significant correlations were observed between FA and the total gait score (r = 0.467, p < 0.01), and also between MD and total gait score (r  = -0.422, p < 0.01). CONCLUSIONS: Patients with CSVD with gait disorders had more WMH of Fazekas scale grade 2-3, lacunes, and total MRI burden than the GN patients, and those with gait disorders may suffer from demyelination of nerve fibers and damage to the fibers' microstructures.

Structural brain network measures in elderly patients with cerebral small vessel disease and depressive symptoms.

OBJECTIVES: To investigate the relationship between diffusion tensor imaging (DTI) indicators and cerebral small vessel disease (CSVD) with depressive states, and to explore the underlying mechanisms of white matter damage in CSVD with depression. METHOD: A total of 115 elderly subjects were consecutively recruited from the neurology clinic, including 36 CSVD patients with depressive state (CSVD+D), 34 CSVD patients without depressive state (CSVD-D), and 45 controls. A detailed neuropsychological assessment and multimodal magnetic resonance imaging (MRI) were performed. Based on tract-based spatial statistics (TBSS) analysis and structural network analysis, differences between groups were compared, including white matter fiber indicators (fractional anisotropy and mean diffusivity) and structural brain network indicators (global efficiency, local efficiency and network strength), in order to explore the differences and correlations of DTI parameters among the three groups. RESULTS: There were no significant differences in terms of CSVD burden scores and conventional imaging findings between the CSVD-D and CSVD+D groups. Group differences were found in DTI indicators (p <  0.05), after adjusting for age, gender, education level, and vascular risk factors (VRF), there were significant correlations between TBSS analysis indicators and depression, including: fractional anisotropy (FA) (r = - 0.291, p <  0.05), mean diffusivity (MD) (r = 0.297, p < 0.05), at the same time, between structural network indicators and depression also show significant correlations, including: local efficiency (ELocal) (r = - 0.278, p < 0.01) and network strength (r = - 0.403, p < 0.001). CONCLUSIONS: Changes in FA, MD values and structural network indicators in DTI parameters can predict the depressive state of CSVD to a certain extent, providing a more direct structural basis for the hypothesis of abnormal neural circuits in the pathogenesis of vascular-related depression. In addition, abnormal white matter alterations in subcortical neural circuits probably affect the microstructural function of brain connections, which may be a mechanism for the concomitant depressive symptoms in CSVD patients.

Dysregulation of Respiratory Center Drive (P0.1) and Muscle Strength in Patients With Early Stage Idiopathic Parkinson's Disease.

Objective: The goal of this study is to evaluate pulmonary function and respiratory center drive in patients with early-stage idiopathic Parkinson's disease (IPD) to facilitate early diagnosis of Parkinson's Disease (PD). Methods: 43 IPD patients (Hoehn and Yahr scale of 1) and 41 matched healthy individuals (e.g., age, sex, height, weight, BMI) were enrolled in this study. Motor status was evaluated using the Movement Disorders Society-Unified PD Rating Scale (MDS-UPDRS). Pulmonary function and respiratory center drive were measured using pulmonary function tests (PFT). All IPD patients were also subjected to a series of neuropsychological tests, including Non-Motor Symptoms Questionnaire (NMSQ), REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ), Beck Depression Inventory (BDI) and Mini Mental State Examination (MMSE). Results: IPD patients and healthy individuals have similar forced vital capacity (FVC), forced expiratory volume in 1s (FEV1), forced expiratory volume in 1s/forced vital capacity (FEV1/FVC), peak expiratory flow (PEF), and carbon monoxide diffusion capacity (DLCOcSB). Reduced respiratory muscle strength, maximal inspiratory pressure (PImax) and maximal expiratory pressure (PEmax) was seen in IPD patients (p = 0.000 and p = 0.002, respectively). Importantly, the airway occlusion pressure after 0.1 s (P0.1) and respiratory center output were notably higher in IPD patients (p = 0.000) with a remarkable separation of measured values compared to healthy controls. Conclusion: Our findings suggest that abnormal pulmonary function is present in early stage IPD patients as evidenced by significant changes in PImax, PEmax, and P0.1. Most importantly, P0.1 may have the potential to assist with the identification of IPD in the early stage.

Needs and rights awareness of stroke survivors and caregivers in urban and rural China: a cross-sectional, multiple-centre questionnaire survey.

OBJECTIVES: Stroke survivors require assistance and support in their daily lives. This survey aims to investigate the needs and rights awareness in Chinese stroke survivors and caregivers in rural and urban settings. SETTING: This survey was adapted from the one created by the World Stroke Organization. The questionnaire included demands for psychological support, treatment and care, social support and information. From January 2015 to January 2016, the survey was pilot tested with urban and rural-dwelling stroke survivors and caregivers from 12 hospitals. Stroke survivors were invited to participate if they were over 18 years old and had experienced a stroke. Exclusion criteria were patients who had disorders of consciousness, significant cognitive impairment, aphasia, communication difficulties or psychiatric disorders. Only caregivers who were family members of the patients were chosen. Paid caregivers were excluded. PARTICIPANTS: One thousand, one hundred and sixty-seven stroke survivors and 1119 caregivers were enrolled. PRIMARY OUTCOME MEASURES: The needs of stroke survivors and caregivers in rural and urban areas were compared. The correlations between needs of rural and urban stroke survivors and caregivers and potential effect factors were analysed, respectively. RESULTS: Among the cohort, 93.5% reported the need for psychological support, 88.6% for treatment and care, 84.8% for information and 62.7% for social support. The total needs and each aspect of needs of stroke survivors in urban settings were greater than of those in rural settings (p<0.01). In rural areas, total needs and each aspect of needs were positively correlated with education level (p<0.01). CONCLUSIONS: Needs and rights awareness of stroke survivors should also be recognised in both urban and rural China. According to the different needs of patients and their caregivers, regional and individualised services were needed by stroke survivors and their caregivers.

Signal molecule-dependent quorum-sensing and quorum-quenching enzymes in bacteria.

The quick spread of nosocomial bacterial infections and the increasing prevalence of drugresistant strains make the development of novel drugs for pathogens an urgent priority. Quorum sensing (QS) is a communication mechanism used by bacteria to recognize population density fluctuations and control gene expression, which play a critical role both in intraspecies and interspecies communications and regulates microbe-host interactions. Low-molecular-weight signal compounds, such as acyl-homoserine lactone and autoinducing peptide, are used by QS to control the expression of different pathogenic factors. Thus QS--and QS signal molecules in particular--is an attractive target for developing novel antimicrobial methods. Quorum-quenching enzymes, which hydrolyze or modify signal molecules in QS circuit systems to inhibit the expression of bacteria virulence factors, have been identified both in prokaryotes and eukaryotes. Understanding the mechanism of action of quorum-quenching enzymes also provides a promising means to control bacterial infection. This review first introduces the novel principle underling signal-based QS systems in several important pathogens and then focuses on the newly identified quorum-quenching enzymes, including lactonases, acylases, oxidoreductases, and paraoxonases; this summary introduces new concepts of antimicrobial infection.

Salmonella enteritidis ghost vaccine induces effective protection against lethal challenge in specific-pathogen-free chicks.

Bacterial ghosts (BGs) are empty bacterial envelopes generated by expulsion of the bacterial genome and cytoplasmic contents from bacterial cells, and the process is mediated by lysis protein E encoded on bacteriophage PhiX174. BGs represent a new approach in vaccine development and have been applied to a variety of gram-negative bacterial vaccine candidates. In this study, a BG vaccine generated from Salmonella enteritidis (S. enteritidis) strain DH091 was prepared using the highly efficient plasmid, pBV-mE. The efficacy of the BG vaccine was tested using 75 chicks (Gallus gallus) kept under specific pathogen-free (SPF) conditions. A comprehensive evaluation of the immune response, including humoral and cellular immune responses, interferon-γ (IFN-γ) and interleukin-4 (IL-4) production, and histopathology of various tissues, was performed in BG-vaccinated animals subsequently challenged with S. enteritidis. The results were compared with animals that were immunized with the inactivated vaccine. S. enteritidis ghosts not only promoted the generation of high titer antibodies and IFN-γ and IL-4 production but also stimulated a significant increase in CD8(+) and CD4(+) T lymphocytes. In particular, the dramatic increase in CD8(+) T cells indicated that the vaccine was able to induce clearance of intracellular Salmonella. The protective effects of BG vaccination in SPF chicks against 5×10(9) colony forming units of S. enteritidis were a result of the induction of a more effective immune response than that observed with the inactivated vaccine. These findings demonstrate the potential of S. enteritidis ghosts to be used as effective vaccines.

Molecular characterization of Mycobacterium tuberculosis complex (MTBC) isolated from cattle in northeast and northwest China.

We studied throat swabs and corresponding serum samples collected from 1067 protein purified derivative (PPD)-tuberculin skin test (TST) positive cattle from different regions of China. The 1067 throat swabs were inoculated onto modified Löwenstein-Jensen medium for the isolation and culture of Mycobacteria. Acid-fast bacilli were identified using traditional biochemical methods, polymerase chain reaction (PCR) amplification and multiplex PCR. They were distinguished as Mycobacterium tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM) strains. An indirect Enzyme-Linked Immunosorbent Assay (ELISA) was applied to detect specific antibodies against bovine TB (bTB). Correlations among the ELISA, bacteriology and TST were analyzed and compared. Spoligotyping and variable number tandem repeats-mycobacterial interspersed repetitive unit (VNTR-MIRU) analysis were used to genotype the MTBC. In total, 111 strains of Mycobacteria were cultured from the 1067 throat swab samples, including 43 stains of MTBC (14 strains of Mycobacterium bovis and 29 of Mycobacterium tuberculosis) and 68 strains of NTM. Thirty-eight MTBC strains and four NTM strains were isolated from 72 throat swab samples that the ELISA determined were antibody positive; five MTBC strains and 64 NTM strains were isolated from 995 throat swab samples that were antibody negative on the ELISA. The positive isolation rates of MTBC and NTM were 38.7% (43/111) and 61.3% (68/111), respectively. The concordance rate of cultured MTBC with a positive result on the indirect ELISA for antibody was 52.8% (38/72), which was much higher than the positive rate for TST (4.0%; 43/1067). Genotyping of the 43 strains of MTBC isolated, using spoligotyping and VNTR-MIRU, showed that the 43 isolates had 26 genotypes; 16 strains had a unique genotype. Two groups of six strains and two strains, respectively, showed the same spoligotyping pattern, and belonged to the Beijing family and Beijing-like family, respectively. Combined application of spoligotyping and VNTR-MIRU typing would improve the molecular epidemiological investigation and monitoring of the etiology of bTB in China.

The migration of styrene butadiene latex during the drying of coating suspensions: when and how does migration of colloidal particles occur?

Surface elemental compositions of model latex clay coatings on an impervious substrate consolidated under various conditions were measured using the XPS technique, in order to clarify when and how colloidal latex particles migrate to the surface during drying. Under similar drying conditions, surface carbon content decreased with the addition of a water-soluble polymer to the coating colors, while remaining virtually unchanged for coatings of different coat weights made with a given color, indicating that surface carbon content variation is mainly caused by migration of latex rather than of water-soluble polymer. The results also showed that for coatings made with a given suspension, surface carbon content decreased with increasing delay time between coating and heating. For coatings frozen during consolidation and dried by sublimation, surface carbon content increased with increasing drying time before freezing. These results suggest that for the model coatings studied, latex migration mainly occurs after coating application before capillary formation during the initial drying stage when coatings are in the liquid phase, contradicting both the conventional capillary transport and boundary wall migration mechanisms. An alternative mechanism which attributes latex migration to surface trapping effect and to higher Brownian mobility of the smaller latex particles compared with pigment appears to provide a systematically consistent explanation to those phenomena. The new particle migration mechanism implies that segregation of colloidal particles is a ubiquitous phenomenon that would occur not only during the drying of paper coatings but also during consolidation of colloidal films containing particles of different sizes. This is of great importance in the control of surface compositions of nanocomposite coatings.

Development and evaluation of an indirect enzyme-linked immunosorbent assay for the detection of antibodies against Campylobacter fetus in cattle.

Campylobacteriosis is a zoonosis that occurs worldwide. Infection with Campylobacter fetus (C. fetus) causes infertility and abortion in sheep and cattle. The current study focuses on the SapA gene of C. fetus that encodes surface array proteins and plays an important role in the virulence of C. fetus. The SapA-N (1398bp) and SapA-C (1422bp) fragments were amplified from the C. fetusSapA gene using polymerase chain reaction (PCR), and the corresponding recombinant proteins rSapA-N and rSapA-C were expressed in Escherichia. coli BL21 cells. Results of Western blotting and enzyme-linked immunosorbent assay (ELISA) showed that the immunological activity of rSapA-N was higher than that of rSapA-C (P<0.05). Therefore, rSapA-N was selected to establish an indirect ELISA for detecting antibodies against C. fetus. The diagnostic criteria were as follows: S/P0.45: positive; S/P<0.4: negative; 0.45>S/P0.4: suspected. The specificity and sensitivity of our method were 94.3% and 88.6%, respectively. Moreover, no cross-reactions were observed between rSapA-N and serum samples that were positive for other bovine bacterial pathogens diseases such as Mycobacterium avium subspecies paratuberculosis. One hundred and two serum samples from cows that had experienced abortion were tested. Four and 2 C. fetus-positive serum samples were found among the 70 bovine brucellosis-positive samples and the 32 infectious bovine rhinotracheitis (IBR)-positive samples, respectively. The findings suggest that the rSapA-N-based ELISA method has immense potential in future applications.