Effects of anteriorly-loaded treadmill walking on dynamic gait stability in young adults

BackgroundAnteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body’s center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.Research questionHow does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?MethodsIn this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.ResultsNo significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η² = 0.114) and liftoff (p = 0.122, η² = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η² = 0.648) and liftoff (p < 0.001, η² = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η² = 0.076).SignificanceCarrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion.     

Diabetes mellitus as a contributory factor in oral candidosis.

It has been reported that poor glycaemic control predisposes to oral candidal infection in diabetic patients. For instance, the carriage of Candida species and the density of candidal growth in the oral cavity is frequently claimed to be increased in patients with diabetes mellitus. However, the validity of these observations remains controversial. Hence, we review and discuss here the clinical data in the literature on the relationship between diabetes and oral candidal carriage and infection, and possible mechanisms associated with its pathogenicity.     

5岁以下健康儿童流感嗜血杆菌携带状态的研究

[目的]流感嗜血杆菌(Hi)是引起儿童细菌性感染的主要病原菌,国内对Hi携带的研究资料较少,本文对石家庄市5岁以下健康儿童Hi感染的流行病学分布情况进行了研究,为制订防治对策提供参考依据。[方法]在石家庄市区整群随机抽样,调查1045例5岁以下健康儿童,取鼻咽拭子标本,用改良巧克力培养基,常规Hi培养并鉴定菌型。[结果](1)Hi携带率为15.6%,生物型Ⅰ、Ⅱ、Ⅲ型共98例(70.5%)为优势菌型。(2)经Logistic多元回归分析显示Hi携带与年龄、出生时身高、家庭人均经济收入和裂纹舌有关。[结论]石家庄市5岁以下正常儿童Hi携带率为15.6%,6个月至2岁儿童Hi携带率最高(22.4%)。Hi携带可能受遗传等综合因素影响。把中医舌诊试用于Hi携带的观察研究,显示了裂纹舌与Hi感染有关,为中西医结合提供参考依据。     

Comparison of nasal swab culture, quantitative culture of nasal mucosal tissue and PCR in detecting Streptococcus pneumoniae carriage in rats

It is not known how well nasopharyngeal swab culture represents pneumococcal carriage status. We tested this by comparing swab culture to quantitative culture and quantitative PCR of mucosal tissue in a rat model of pneumococcal carriage. Quantitative culture and quantitative PCR identified significantly more carriers compared to swab culture (differences 15% and 33%, 95% CI 1-28% and 16-47%, p=0.04 and 0.001, respectively). The sensitivity and specificity of swab culture was 75/92% and 63/100% compared to quantitative tissue culture and quantitative PCR, respectively. The quantitative estimates of culture and PCR were very similar (Pearson correlation coefficient 0.79, p<0.001). In conclusion, even a well-controlled swab sampling markedly underestimates pneumococcal carriage rate, and simultaneous use of quantitative culture and PCR increases the number of positive samples by about one third.     

Serotypes of carriage and invasive isolates of Streptococcus pneumoniae in Brazilian children in the era of pneumococcal vaccines

Nasopharyngeal carriage of Streptococcus pneumoniae is a key factor in the development of invasive disease and the spread of resistant strains within the community. A single nasopharyngeal swab was obtained from 648 unvaccinated children aged <5 years, either healthy or with acute respiratory tract infection or meningitis, during the winters of 2000 and 2001. The overall pneumococcal carriage rate was 35.8% (95% CI 32.1-39.6). The pneumococcal serotypes found most frequently in the nasopharynx were 14, 6B, 6A, 19F, 10A, 23F and 18C, which included five of the seven serotypes in the currently licensed seven-valent conjugate vaccine (PCV7); serotypes 4 and 9V were less common. Serotypes 1 and 5 were isolated rarely from the nasopharynx. A comparison of 222 nasopharyngeal isolates with 125 invasive isolates, matched for age and time to the carrier isolates, showed a similar prevalence of penicillin non-susceptible pneumococci (PNSp) (19.8% and 19.2%, respectively). PNSp serotypes were similar (6B, 14, 19F, 19 A, 23B and 23F) for carriage and invasive disease isolates. The coverage of PCV7 for carriage isolates (52.2%) and invasive isolates (62.4%) did not differ significantly (p 0.06); similarly, there was no significant difference in PCV7 coverage for carriage isolates (34.5%) and invasive isolates (28.2%) of PNSp. These data suggest that PCV7 has the potential to reduce pneumococcal carriage and the number of carriers of PNSp belonging to vaccine serotypes.     

Antimicrobial resistance of nasopharyngeal pneumococci from children from day-care centres and orphanages in Russia: results of a unique prospective multicentre study

This study assessed the antimicrobial resistance of nasopharyngeal pneumococci isolated from children aged < 5 years in day-care centres and orphanages throughout Russia during 2001-2002. Swabs were collected from 2484 children in 43 day-care centres and eight orphanages in 11 cities of European Russia, and from 1669 children in 37 day-care centres and three orphanages in eight cities of Asian Russia, with a total of 1144 and 912 Streptococcus pneumoniae isolates being recovered in European and Asian Russia, respectively. All macrolide-non-susceptible (MICs 0.5-128 mg/L) and fluoroquinolone-non-susceptible (ciprofloxacin MICs > or = 4 mg/L) isolates were tested for resistance mechanisms and clonal relatedness. Non-susceptibility rates, by CLSI criteria, were 19.3%, 0.9% and 0.4% for penicillin G, cefotaxime and amoxycillin-clavulanate, respectively. Resistance to macrolides and lincosamides was also relatively low, i.e., < 7% for clindamycin and 14- and 15-membered macrolides. The highest rates of non-susceptibility were for tetracycline and co-trimoxazole (52.0% and 64.5%, respectively). No clones resistant to ciprofloxacin (MICs > or = 8 mg/L) were found, but 1.7% of isolates were non-susceptible (MIC 4 mg/L). No resistance was found to levofloxacin, gemifloxacin, telithromycin or vancomycin. Pulsed-field gel electrophoresis analysis showed no relationship between ciprofloxacin- and macrolide-non-susceptible isolates in European and Asian Russia. Resistance among macrolide-resistant isolates resulted mostly from the presence of erm(B) and mef(A), and from changes in L4; additionally, L22 mutations were common in isolates from Asian Russia. Non-susceptibility to quinolones was associated with mutations in parC and parE among European isolates. Asian Russian isolates had mutations in parC and gyrA, and alterations in parE were more common. There were substantial differences in non-susceptibility and mechanisms of resistance between pneumococci from Asian and European Russia, with orphanages appearing to be 'hot-spots' of resistance.     

Evidence for re-infection and persistent carriage of Shigella species in adult males reporting domestically acquired infection in England

ObjectivesWe analysed national surveillance typing data of Shigella isolated from adult males with domestically acquired infection (a cohort largely consisting of men who have sex with men (MSM)) to establish whether multiple isolates from the same individual over time represented persistent carriage or re-infection.MethodsWe carried out a retrospective cohort study of adult males diagnosed with Shigella from 2004 to 2018. Median time intervals between multiple isolations of Shigella flexneri and S. sonnei were compared. Analysis of whole genome sequencing data provided strain discrimination at the single nucleotide level and was used to quantify the genetic distance among isolates. Maximum likelihood phylogenies were constructed to determine whether persistent carriage (characterized by multiple isolations of the same strain) or re-infection (characterized by multiple isolations of different strains) was best supported by the phylogenetic analysis. A comparison analysis was carried out using data linked to adult females with domestically acquired shigellosis.ResultsThe number of men reporting multiple isolations of Shigella species was 165/4733 (3.5%) compared with 31/2423 (1.3%) females (p < 0.001). For isolate pairs from men associated with persistent carriage, the isolation time interval range was 6–176 days (median 23.5; IQR 8–70) and single nucleotide polymorphism (SNP) distance range was 0–7 SNPs (median 0.5; IQR 0–2). For those associated with re-infection, the isolation time interval was 34–2636 days (median 732; IQR 191–1258) and the SNP distance was 10–1462 SNPs (median 120; IQR 29–377).DiscussionMultiple Shigella isolations in individuals with domestically acquired infections was more frequently observed in adult males than in adult females. Following the acute phase of infection, carriage can persist for months, and infection can recur within months, even with strains belonging to the same species and the same serotype. A combination of multiple sexual partners, persistent carriage following the acute phase of infection and evidence of recurrent re-infection is likely to contribute to sustained transmission in this population.     

Prevalence of human papillomaviruses in the healthy oral mucosa of women with high‐grade squamous intra‐epithelial lesion and of their partners as compared to healthy controls

Oral human papillomavirus (HPV) carriage rates were investigated in relation to genital HPV carriage in women with HPV‐associated cervical lesions and male partner of such women, including several couples, in comparison with healthy individuals. Buccal and lingual mucosa of 60 males and 149 females with healthy oral mucosa and without known genital lesion, genital and oral mucosa of further 40 females with cervical high‐grade squamous intraepithelial lesion (HSIL) and 34 male sexual partners of women with HSIL (including 20 couples) were sampled. HPV DNA was detected using MY/GP PCR. Genotype was determined by sequencing or restriction fragment length polymorphism. Virus copy numbers were determined by real‐time PCR. Overall, oral HPV carriage rate was 5.7% (12/209) in healthy individuals; average copy number was 5.8 × 10² copies/1 μg DNA; male and female rates were comparable. Oral carriage in women with HSIL was significantly higher, 20.0% (8/40, P = 0.003); males with partners with HSIL showed a carriage rate of 17.6% (6/34), copy numbers were similar to the healthy controls. In contrast, genital carriage rate (52.9%, 18/34 vs. 82.5%, 33/40; P = 0.006) and average copy number were lower in males (5.0 × 10⁵ vs. 7.8 × 10⁵ copies/1 μg DNA; P = 0.01). Oral copy numbers in these groups and in healthy individuals were comparable. High‐risk genotypes were dominant; couples usually had the same genotype in the genital sample. In conclusion, genital HPV carriage is a risk factor of oral carriage for the individual or for the sexual partner, but alone is not sufficient to produce an oral HPV infection in most cases.     

Multidrug-Resistant Enterobacteriaceae Colonising the Gut of Adult Rural Population in South India

Background: Multidrug-resistant (MDR) colonisers act as a reservoir for transmission of antibiotic resistance and are a source of infection. Exposure to antibiotics by the commensal flora renders them resistant. Antibiotic consumption and hospitalisation are two major factors influencing this. We studied, antibiotic-resistant bacteria colonising rural adult population who had restricted access to health care and presumably had low consumption of antibiotics. Aim: Detection of multidrug resistance genes of extended spectrum β-lactamase (ESBL-CTX-M), AmpC β-Lactamase (CIT), Klebsiella pneumoniae carbapenemase (KPC) and New Delhi Metallo β-lactamase (NDM) in Enterobacteriaceae colonising the gut of adult population in a South Indian rural community. Methodology: Faecal samples of 154 healthy volunteers were screened for Enterobacteriaceae resistant to commonly used antibiotics by standard methods, followed by phenotypic detection of ESBL by double disk synergy method, AmpC by spot inoculation and carbapenemases by imipenem and ethylenediaminetetraacetic acid + imipenem combined E-test strips and modified Hodge test. Polymerase chain reaction was done to detect bla_CTX-M, bla_CIT, bla_KPC-1 and bla_NDM-1 genes coding for ESBL, AmpC, KPC and NDM, respectively. Results: Colonisation rate of enteric bacteria with MDR genes in the community was 30.1%. However, phenotypically, only ESBL (3.2%) and NDM (0.65%) were detected. While the genes coding for ESBL, AmpC and NDM were detected in 35.6%, 17.8% and 4.4% of the MDR isolates, respectively. Conclusions: Carriage of MDR strains with a potential to express multidrug resistance poses a threat of dissemination in the community. Awareness for restricted use of antibiotics and proper sanitation can contain the spread of resistant bacteria.