Instrumented measurement of anterior-posterior laxity of the knee joint after tibial plateau fracture

The Knee Signature System (KSS) was used to measure anterior-posterior laxity of the knees of 34 patients who had an old tibial plateau fracture. The mean total tibial translation with respect to the femur was 9.8 (range 3.1–19.5) mm in the injured knees and 7.5 (range 3.1–14.2) mm in the uninjured knees (P < 0.01). A side-to-side difference (injured versus uninjured knee) to 3 mm or more was found in 13 knees (38%). Neither mode of treatment nor extent of residual displacement of the condyles had any correlation with the sagittal translation. Because complete rupture of cruciate ligaments in association with tibial plateau fracture has been proven to be uncommon and changes in bony configuration did not affect the result, the abnormal tibial translation was left to be a consequence of stretching of the ligaments increasing multi-dimensional instability of the knee joint. The phenomenon was found more pronounced in older patients whose tolerance of ligaments and other soft tissues against stretching forces is decreased. Therefore, when using the KSS device, a side-to-side difference of 3 mm or more in sagittal translation of the tibia with respect to the femur is not always an indication of anterior cruciate ligament deficiency, when such differences are found in patients with an old tibial plateau fracture.     

Oligonucleotide probes to the 16s ribosomal RNA: implications of sequence homology and secondary structure with particular reference to the oral species Prevotetla intermedia and Prevotetla nigrescens

Eight oligonucleotides based upon regions of the small subunit 165 ribosomal RNA gene sequences were analysed against a background of their position within the molecule and their two-dimensional structure to rationalise their use in recognising Prevotetla intermedia and Prevotetla nigrescens . The 41 clinical isolates from both oral and respiratory sites and two reference strains were subjected to DNA-DNA hybridisation and multilocus enzyme etectrophoresis to confirm their identity. Alignment of oligonucleotide probes designated I Bi-2 to I Bi-6 (for P. intermedia ) and 2Bi-2 (for P. nigrescens ) with the 165 rRNA suggested that these probes lacked specificity or were constructed from hypervariable regions. A 52– mer oligonucleotide (designated Bi) retiably detected both species. Because of the high degree of concordance between the I 65 rRNAs of both species, it was necessary to vary the stringency of hybridisation conditions for detection of both species. Thus probe I Bi-I recognised P. intermedia while I Bi-l detected both P. intermedia and P. nigrescens at low stringency. However, under conditions of high stringency only P. nigrescens was recognised by probe 2Bi-I. These probes were highly specific and did not hybridise with DNA from the closety retated P. corporis , nor other periodontal pathogens such as Fuso-bacterium nucleatum, Actinobacillus actinomycetemcomit-ans , Treponema denticola and several pigmented species such as Prevotetla metoninogenica, P. denticola, P. loescheii, Porphyramonas osaccharolytica, Py. endodontalis, Py. gin-givalis, Py . levii, and Py. macacae .     

Methaemoglobin formation after the use of EMLA cream in term neonates

EMLA cream 5% (a eutectic mixture of lidocaine and prilocaine) is a topical anaesthetic that has become widely used to minimize pain from venipuncture in children. It has not, however, been recommended in neonates owing to the potential risk of methaemoglobinaemia induced by prilocaine. The aim of this study was to establish the safety of 1 g EMLA cream 5% used on intact skin in term neonates. Forty-seven neonates, aged 0-3 months, with a postconceptual age of ≥37 weeks and a body weight between 2.8 and 5.7 kg, were included in a double-blind, randomized, placebo-controlled study. After baseline observations a total dose of 1.0 g EMLA/placebo was applied to two sites (0.5 g site⁻¹) for 60-70 min. Venous methaemoglobin (metHb) levels were determined in each patient at baseline and at three randomly assigned times, 0.5-18h after application. Following application of the cream, the mean metHb levels were 1.17% (range 0.50-2.53) in the EMLA group and 0.96% (range 0.50-1.53) in the placebo group. The metHb concentrations were significantly higher in the EMLA group in the intervals from 3.5 to 13 h after application than in the placebo group, but were well below potentially harmful levels. Based on these results, a 1-h application of 1 g EMLA cream is safe when used on the intact skin of term neonates below 3 months of age.     

Multiplex ligation-dependent probe amplification analysis to screen for deletions and duplications of the LDLR gene in patients with familial hypercholesterolaemia

The most common genetic defect in patients with autosomal dominant hypercholesterolaemia is a mutation of the low-density lipoprotein receptor ( LDLR ) gene. An estimate of the frequency of major rearrangements has been limited by the availability of an effective analytical method and testing of large cohorts. We present data from a cohort of 611 patients referred with suspected heterozygous familial hypercholesterolaemia (FH) from five UK lipid clinics, who were initially screened for point mutations in LDLR and the common APOB and PCSK9 mutations. The 377 cases in whom no mutation was found were then screened for large rearrangements by multiplex ligation-dependent probe amplification (MLPA) analysis. A rearrangement was identified in 19 patients. This represents 7.5% of the total detected mutations of the cohort. Of these, the majority of mutations (12/19) were deletions of more than one exon, two were duplications of more than one exon and five were single exon deletions that need interpreting with care. Five rearrangements (26%) are previously unreported. We conclude that MLPA analysis is a simple and rapid method for detecting large rearrangements and should be included in diagnostic genetic testing for FH.     

Hand hygiene practices among community Health Officers in Rivers State,Nigeria

Background

Health care associated infections are most commonly transmitted by the hands of Health care workers and other hospital personnel.

Objective

To investigate compliance with hand hygiene guidelines and methods of hand hygiene practice among community health officers in Rivers State Nigeria.

Methods

Self administered questionnaires were distributed to 68 community health officers. The questionnaires consisted of 19 items which contained information on bio-demographic characteristics and hand hygiene practices. Data were analysed using SPSS-16 statistical software. Proportions were compared using Chi- square test and ‘p’ value less than 0.05 was considered statistically significant.

Results

The response rate was 97.1%. There were 11 (16.7%) males and 55 (83.3%) females with a male to female ratio of 1: 5. The age of the participants ranged from 28–56 years with a mean age of 39.7±6.7. Washing of hands before and after contact with patient was 60.1% and 97% respectively. The difference was significant (p<0.01). Allergy to gloves was 15.2%. About three-quarter (77.3%) of the workers used soap and water to wash the hands when soiled or visibly contaminated. None of the workers used alcohol hand rub.

Conclusion

Though there was improved compliance to hand hygiene guidelines, this still fall short of acceptable standards. The provision and promotion of the proper use of alcohol-based hand rub may further improve compliance with hand hygiene by reducing the time required to perform it and the convenience of the method.     

Government trust,perceptions of COVID-19 and behaviour change: cohort surveys,Singapore

ObjectiveTo evaluate how public perceptions and trust in government communications affected the adoption of protective behaviour in Singapore during the coronavirus disease 2019 (COVID-19) pandemic.MethodsWe launched our community-based cohort to assess public perceptions of infectious disease outbreaks in mid-2019. After the first case of COVID-19 was reported in Singapore on 23 January, we launched a series of seven COVID-19 surveys to both existing and regularly enrolled new participants every 2 weeks. As well as sociodemographic properties of the participants, we recorded changing responses to judge awareness of the situation, trust in various information sources and perceived risk. We used multivariable logistic regression models to evaluate associations with perceptions of risk and self-reported adopted frequencies of protective behaviour.FindingsOur cohort of 633 participants provided 2857 unique responses during the seven COVID-19 surveys. Most agreed or strongly agreed that information from official government sources (99.1%; 528/533) and Singapore-based news agencies (97.9%; 522/533) was trustworthy. Trust in government communication was significantly associated with higher perceived threat (odds ratio, OR: 2.2; 95% confidence interval, CI: 1.6–3.0), but inversely associated with perceived risk of infection (OR: 0.6; 95% CI: 0.4–0.8) or risk of death if infected (OR: 0.6; 95% CI: 0.4–0.9). Trust in government communication was also associated with a greater likelihood of adopting protective behaviour.ConclusionOur findings show that trust is a vital commodity when managing an evolving outbreak. Our repeated surveys provided real-time feedback, allowing an improved understanding of the interplay between perceptions, trust and behaviour.     

A prospective study of NAT2 acetylation genotype, cigarette smoking, and risk of breast cancer

Polymorphisms in the N-acetyltransferase 2 (NAT2) gene are determinants of the rate of metabolic activation of carcinogenic compounds such as aryl aromatic amines. Homozygosity for any combination of three variant alleles in Caucasians defines 'slow' acetylators; presence of one or two wild-type alleles characterizes 'rapid' acetylators. Although most previous studies have not observed an overall elevation in risk of breast cancer among slow acetylators, a recent study observed that cigarette smoking was associated with a large increase in risk of breast cancer among slow acetylators. We assessed the relation between NAT2 acetylation status and breast cancer risk, and its interaction with smoking, in a prospective study of mainly Caucasian US women. Four hundred and sixty-six incident cases who were diagnosed with breast cancer after giving a blood specimen in 1989-90 were matched to 466 controls in a nested case-control study. NAT2 genotype was determined using PCR-RFLP assays. The multivariate relative risk (RR) comparing slow with rapid acetylators was 0.9 (95% CI 0.7-1.2). Among slow acetylators, current smoking immediately prior to diagnosis was not associated with a significant elevation in risk compared with never smoking rapid acetylators (RR = 1.4, 95% CI 0.7-2.6). No significant association was seen between pack-years of smoking and risk of breast cancer among either slow or fast acetylators. A non-significant elevation in risk was observed among women who smoked for > or = 5 years prior to first pregnancy and were rapid acetylators, compared with never smoking rapid acetylators (RR = 1.5, 95% CI 0.9-2.6). In analyses limited to 706 post-menopausal women, the elevated risks for current smokers immediately prior to diagnosis who were slow acetylators compared with never smokers who were fast acetylators were slightly stronger but still not statistically significant. In summary, we observed little evidence of an association between NAT2 genotype and breast cancer. In this prospective study, cigarette smoking was not appreciably associated with breast cancer among either slow or fast NAT2 acetylators.