Evaluation of PCR primers to identify Porphyromonas endodontalis in apical periodontitis clinical samples

We aimed to evaluate whether two commonly used PCR primers are effective to identify P. endodontalis and discriminate from other prevalent black-pigmented bacteria in apical periodontitis (AP). Endodontic canal samples from patients with asymptomatic AP (n = 20) were collected and cultured in anaerobiosis. Two primer sets to detect P. endodontalis were selected from the literature and first analyzed for their specificity in silico; and then tested on clinical isolates in vitro and finally, in apical exudates ex vivo. The identity of P. endodontalis was verified by PCR and Sanger sequencing with universal primers for bacterial V3-V6 regions 16S rDNA. Only one primer set showed specificity only for P. endodontalis clones in silico and also was specific for P. endodontalis in vitro and ex vivo.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Maternal periconceptional and first trimester protein restriction in beef heifers: effects on placental parameters and fetal and neonatal calf development

Few studies have investigated the effects of nutrition during the periconception and early gestation periods on fetal and placental development in cattle. In this study, nulliparous yearling heifers (n=360) were individually fed a diet high or low in protein (HPeri and LPeri) beginning 60 days before conception. From 24 to 98 days after conception, half of each treatment group was changed to the alternative high- or low-protein diet (HPost and LPost) yielding four groups in a 2×2 factorial design. A subset of heifers (n=46) was necropsied at 98 days after conception and fetoplacental development assessed. Placentome number and volume decreased in response to LPeri and LPost diets respectively. Absolute lung, pancreas, septum and ventricle weights decreased in LPost versus HPost fetuses, whereas the post-conception diet altered absolute and relative liver and brain weights depending on sex. Similarly, changes in fetal hepatic gene expression of factors regulating growth, glucose output and lipid metabolism were induced by protein restriction in a sex-specific manner. At term, neonatal calf and placental measures were not different. Protein restriction of heifers during the periconception and early gestation periods alters fetoplacental development and hepatic gene expression. These changes may contribute to functional consequences for progeny, but this may not be apparent from gross morphometry at birth.

The Salivary Mycobiome Contains 2 Ecologically Distinct Mycotypes

A broad range of fungi has been detected in molecular surveys of the oral mycobiome. However, knowledge is still lacking on interindividual variability of these communities and the ecologic and clinical significance of oral fungal commensals. In this cross-sectional study, we use internal transcribed spacer 1 amplicon sequencing to evaluate the salivary mycobiome in 59 subjects, 36 of whom were scheduled to receive cancer chemotherapy. Analysis of the broad population structure of fungal communities in the whole cohort identified 2 well-demarcated genus-level community types (mycotypes), with Candida and Malassezia as the main taxa driving cluster partitioning. The Candida mycotype had lower diversity than the Malassezia mycotype and was positively correlated with cancer and steroid use in these subjects, smoking, caries, utilizing a removable prosthesis, and plaque index. Mycotypes were also associated with metabolically distinct bacteria indicative of divergent oral environments, with aciduric species enriched in the Candida mycotype and inflammophilic bacteria increased in the Malassezia mycotype. Similar to their fungal counterparts, coexisting bacterial communities associated with the Candida mycotype showed lower diversity than those associated with the Malassezia mycotype, suggesting that common environmental pressures affected bacteria and fungi. Mycotypes were also seen in an independent cohort of 24 subjects, in which cultivation revealed Malassezia as viable oral mycobiome members, although the low-abundance Malassezia sympodialis was the only Malassezia species recovered. There was a high degree of concordance between the molecular detection and cultivability of Candida, while cultivation showed low sensitivity for detection of the Malassezia mycotype. Overall, our work provides insights into the oral mycobiome landscape, revealing 2 community classes with apparently distinct ecologic constraints and specific associations with coexisting bacteria and clinical parameters. The utility of mycotypes as biomarkers for oral diseases warrants further study.

Choosing foods for infants: a qualitative study of the factors that influence mothers

BACKGROUND

Examining the experiences of parents making food choices for infants is important because ultimately this influences what infants eat. Infancy is a critical period when food preferences and eating behaviour begin to develop, shaping dietary patterns, growth and health outcomes. There is limited evidence regarding what or why foods are chosen for infants.

OBJECTIVE

To describe the experiences of mothers making food choices for their infant children.

METHODS

Semi-structured interviews with 32 Australian mothers of infants aged four to 15 months from a range of socioeconomic backgrounds. An inductive thematic analysis through a process of constant comparison was conducted on transcribed interviews.

RESULTS

Mothers described many ideas and circumstances which influenced food choices they made for infants. Themes were developed which encapsulate how the wider environment and individual circumstances combine to result in the food choices made for infants. Beliefs, values, norms and knowledge were a central influence on choices. Cost, quality and availabilities of various foods were also key factors. Related to this, and combined with inherent factors such as perishability and infant acceptability, fresh fruits and vegetables were often singled out as an easy or difficult choice. Influences of time, parents' capacities, social connections and different information sources were clearly apparent. Finally infants' own preferences and how parents helped infants with learning to eat were also key influences on food choices.

CONCLUSIONS

Choosing foods for infants is a complex social practice. An ecological framework depicting the multiple influences on what people eat and sociological theory on food choice regarding the role of 'social structure' and 'human agency' are both applicable to the process of choosing foods for infants. Equity issues may be key regarding the degree to which mothers can choose particular foods for infants (e.g. choosing foods which promote health).

An exploration of the views of Australian mothers on promoting child oral health

BACKGROUND

An important role for parents and caregivers in the prevention of dental caries in children is the early establishment of health promoting behaviours. This study aimed to examine mothers' views on barriers and facilitators to promoting child and family oral health.

METHODS

Semi-structured interviews were undertaken with a purposive sample of mothers (n = 32) of young children. Inductive thematic analysis was conducted.

RESULTS

Parental knowledge and beliefs, past experiences and child behaviour emerged as major influences on children's oral health. Child temperament and parental time pressures were identified as barriers to good oral health with various strategies reported for dealing with uncooperative children at toothbrushing time. Parental oral health knowledge and beliefs emerged as positive influences on child oral health; however, while most mothers were aware of the common causes of dental caries, very few knew of other risk factors such as bedtime feeding. Parents' own oral health experiences were also seen to positively influence child oral health, regardless of whether these were positive or negative experiences.

CONCLUSIONS

Understanding parental oral health beliefs is essential to overcoming barriers and promoting enablers for good child oral health. Improving child oral health also requires consideration of child behaviour, family influences, and increasing awareness of lesser-known influencing factors.

The Porphyromonas gingivalis O antigen is required for inhibition of apoptosis in gingival epithelial cells following bacterial infection

BACKGROUND AND OBJECTIVE

Porphyromonas gingivalis infection induces apoptosis inhibition in gingival epithelial cells; however, it is not fully understood which bacterial effectors are involved in this process. The aim of this study is to evaluate whether the P. gingivalis lipopolysaccharide (LPS), specifically the O-antigen region, affects adherence, invasion, viability and apoptosis of gingival epithelial cells.

MATERIAL AND METHODS

Gingival epithelial cells (OKF6/TERT2 line) were infected by different freshly prepared P. gingivalis clinical isolates, obtained from subjects with chronic periodontitis (CP3 and CP4) and healthy individuals (H1 and H3). Periodontitis and healthy isolates show differences in O-antigen production, as healthy isolates lack the O-antigen region. In addition, cells were infected by a site-specific mutant lacking the O-antigen portion. After 24 h postinfection, cell proliferation, viability and apoptosis were evaluated by Trypan blue, MTS and annexin V assays, respectively. Bacterial invasion, adhesion and proliferation were measured by gentamicin/metronidazole protection assays. Finally, toll-like receptor (TLR)2 and TLR4 mRNA expression was evaluated by quantitative reverse transcription-polymerase chain reaction. Statistical analysis was performed using ANOVA, Tukey's or Dunnett's tests (p < 0.05).

RESULTS

At 24 h postinfection, strains lacking the O-antigen region (healthy isolates and O-antigen ligase-deficient strain) were unable to increase proliferation and viability, or decrease apoptosis as compared with strains producing intact LPS (periodontitis isolates and reference strain). However, the presence of the O-antigen neither contributed to changes in the ability of the bacteria to adhere to or invade cells, nor to intracellular survival. The presence of O-antigen also increased the expression of TLR4 (nearly sixfold), which correlated with inhibition of apoptosis.

CONCLUSION

The O-antigen region of P. gingivalis LPS is required to increase gingival epithelial cell viability upon infection by bacteria and this increase is attributable to a reduction in apoptosis. Moreover, although bacterial internalization is required, the effects observed are not due to alterations in P. gingivalis adherence, invasion or intracellular survival. Interestingly, inhibition of apoptosis correlates with increased TLR4 expression, suggesting a role for TLR4 in this process.

Fetal programming in 2-year-old calving heifers: peri-conception and first trimester protein restriction alters fetal growth in a gender-specific manner

Protein restriction in early bovine gestation affects post-natal reproduction and production traits in progeny. This experiment evaluated the effects of dietary protein restriction during the peri-conception period and first trimester in yearling heifers on conceptus growth and development; this period of dietary intervention being earlier than any previous bovine fetal programming studies. Three-hundred and sixty primiparous 12-month-old Santa Gertrudis heifers were individually fed high [14% crude protein (CP)] or low (7% CP) diets for 60 days before conception. At 23 days post-conception (dpc), each high (HPERI) or low (LPERI) group was again split into high (HPOST) or low (LPOST) protein groups yielding four treatment groups in a 2 × 2 factorial design. From the end of the first trimester of gestation (98dpc), the pregnant heifers were individually fed a 12% CP diet until parturition. Forty-six fetuses were excised at 98dpc. Sixty-four heifers went on to calve. Conceptus development was assessed via transrectal ultrasound from 36dpc, fetal necropsy at 98dpc and live calf measures at term. At 36dpc, HPERI diet increased fetal crown–rump length (CRL) (P < 0.05) and at the 60dpc scan, biparietal diameter (BPD) tended to be increased by HPOST diet (P < 0.1) though the greater effect upon BPD was still the HPERI diet (P < 0.05). At 60dpc, BPD in the male fetus was affected by the peri-conception diet (P < 0.05), while in females, BPD was not different among nutritional groups. These ultrasound measures of fetal growth were validated by measures of the excised fetus at 98dpc. Fetal weight was heavier (P < 0.01) in those whose mothers were fed the HPOST diet than their LPOST counterparts. Males fetuses were heavier than female fetuses (P < 0.001). Fetal CRL was increased by HPERI diet (P < 0.05) and tended to be increased by HPOST diet (P < 0.1). Fetal BPD tended to be increased by HPERI diet (P < 0.1). In males, BPD tended to be increased in those fetuses whose mothers were fed HPERI (P < 0.1). For females, maternal nutrition during PERI or POST did not affect BPD at 98dpc (P > 0.1). At term, no dietary effect on birthweight was observed (P > 0.1) and males were not heavier than females (P > 0.1). These results suggest that maternal protein intake during the peri-conception (–60 to 23dpc) and first trimester (24–98dpc) may influence early conceptus growth and development in the bovine. The long-term effects on offspring metabolism and post-natal development of this dietary intervention are yet to be determined.

A confidential inquiry into asthma deaths in Wales

BACKGROUND

Death from asthma is regarded as preventable in principle, especially under the age of 65 years.

METHODS

In 1994 a confidential inquiry was set up to investigate deaths attributable to asthma in residents of Wales under the age of 65 years. During the period of the inquiry 92 cases were notified as being ascribed to asthma, or (in 1996) having a mention of asthma on the death certificate. Of these, 80 were investigated further with the help of general practitioners, hospital notes, and relatives. The details were then considered by a small panel of doctors who endeavoured to identify factors that may have contributed to the deaths.

RESULTS

Asthma was considered to be the underlying cause of 52 deaths. Although disease severity was usually a major factor, some aspect of the patient's behaviour or circumstances seemed to have contributed to 31 deaths, while in 15 cases there was probably a deficiency in medical care.

CONCLUSIONS

Some preventable asthma deaths still occur, particularly in relation to inadequate treatment. Factors associated with patients' behaviour and circumstances are more difficult to tackle but, if doctors are aware of high risk patients, increased vigilance may prevent some deaths.

Incidence of psychotic illness in London: comparison of ethnic groups

OBJECTIVE

To compare annual incidences of psychosis in people from different ethnic groups as defined in the 1991 census.

SETTING

Catchment area of district psychiatric hospital.

DESIGN

All people aged 16 to 54 years who made contact with a wide range of community and hospital services between 1 July 1991 and 30 June 1992 were screened for psychotic symptoms. Patients with such symptoms were interviewed face to face to collect information on demography, ethnic group, psychiatric history and symptoms, drug use, and how care had been sought. A key informant, usually a close relative, was also interviewed.

MAIN OUTCOME MEASURES

Age standardised incidence of schizophrenia and non-affective psychosis according to the ninth edition of the International Classification of Diseases in each ethnic group.

RESULTS

Ninety three patients took part, of whom 38 were assigned a certain or very likely diagnosis of schizophrenia (15 in white population, 14 in black, seven in Asian, and two in others). The age standardised annual incidence of schizophrenia was 2.2 (95% confidence interval 1.5 to 2.9) per 10,000 of the population. The incidence ratio for schizophrenia in all ethnic minority groups compared with the white population was 3.6 (1.9 to 7.1); the corresponding figure for non-affective psychosis was 3.7 (2.2 to 6.2).

CONCLUSIONS

Raised incidences of schizophrenia were not specific to the African Caribbeans, which suggests that the current focus on schizophrenia in this population is misleading. Members of all ethnic minority groups were more likely to develop a psychosis but not necessarily schizophrenia. The personal and social pressures of belonging to any ethnic minority group in Britain are important determinants in the excess of psychotic disorders found.

Thyrotoxicosis and hypercalcaemia: response to antithyroid drugs and salmon calcitonin

Four patients with thyrotoxicosis, hypercalcaemia and metabolic bone disease are described. One of them had a 'hot nodule', T3 toxicosis and a parathyroid tumour and another had thin bones, subperiosteal cortical bone erosions and complete dysphagia. Hypercalcaemia persisted during treatment with antithyroid drugs in two patients, both of whom had hyperparathyroidism. The administration of salmon calcitonin to these two patients before starting antithyroid treatment produced an immediate and sustained fall in serum calcium and urinary hydroxyproline levels. Calcitonin administration should be of value in the early management of hypercalcaemic patients.