Perceived stress and well-being in UK and Australian dental hygiene and dental therapy students.

INTRODUCTION: This study aimed to explore United Kingdom (UK) and Australian (Aus) dental hygiene and dental therapy students' (DHDTS) perception of stress and well-being during their undergraduate education. Upon qualification, DHDTS in the UK register as dental therapists (DT), and in Australia, they register as Oral Health Therapists (OHT). MATERIALS AND METHODS: A questionnaire was distributed to years 1, 2 and 3 DHDTS at the University of Portsmouth Dental Academy (UPDA) in the UK and La Trobe Rural Health School in Australia. The questionnaire consisted of 5 well-used measurement instruments which included the following: Dental Environment Stress questionnaire (DES); Depression Anxiety Stress Scales (DASS-21); Scales of Psychological Well-Being (SPWB); Valuing Questionnaire (VQ); and the Adult Hope Scale (AHS) to collect data on students' perception of levels of stress and well-being. RESULTS: A response rate of 58% (UK) and 55% (Australia) was achieved. Clinical factors and academic work were perceived as stressful for DHDTS in both the UK and Australia. The Australian DHDTS-perceived stress in the educational environment was significantly higher (P < .002) than the UK DHDTS. The majority of respondents reported levels of depression, anxiety and stress to be within the normal-to-moderate range. All students reported high levels of positive well-being, with no significant differences between the 2 groups. CONCLUSIONS: DHDTS in the UK and Australia identified sources of stress within their undergraduate education, but also perceived themselves as positively functioning individuals.

Previously diagnosed influenza infections and the risk of developing epilepsy.

Several epidemiological studies suggest a possible involvement of viral infection in the development of epilepsy. While recent research from in vitro studies increasingly supports the role of herpes simplex virus type 1 (HSV-1) in the pathogenesis of epilepsy, little is known about the role of other viral infections such as influenza. Using data from the Clinical Practice Research Datalink (CPRD), we conducted a matched case-control analysis to assess the association between GP-diagnosed influenza infections and the risk of developing an incident diagnosis of epilepsy. During the study period 11 244 incident epilepsy cases and 44 976 matched control patients were identified. Prior exposure to influenza was reported in 7·5% of epilepsy cases and 6·7% of controls [adjusted odds ratio (aOR) 1·12, 95% confidence interval (CI) 1·03-1·22]. Prior history of 'complicated influenza', i.e. influenza associated with a possible super-infection, was associated with a slightly increased epilepsy risk (aOR 1·64, 95% CI 1·10-2·46), particularly if recorded within the 2 months preceding the epilepsy diagnosis (aOR 6·03, 95% CI 1·10-33·2). Our findings suggest that prior influenza exposure does not appear to materially alter the risk of developing epilepsy. By contrast, influenza episodes accompanied by complications were associated with a slightly increased epilepsy risk.

Non-steroidal anti-inflammatory drug and aspirin use and the risk of head and neck cancer.

BACKGROUND: Evidence for non-steroidal anti-inflammatory drugs (NSAIDs) preventing head and neck cancer (HNC) is inconclusive; however, there is some suggestion that aspirin may exert a protective effect. METHODS: Using data from the United States National Cancer Institute Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, we examined the association between aspirin and ibuprofen use and HNC. RESULTS: Regular aspirin use was associated with a significant 22% reduction in HNC risk. No association was observed with regular ibuprofen use. CONCLUSION: Aspirin may have potential as a chemopreventive agent for HNC, but further investigation is warranted.

Paired donor interchange to avoid ABO-incompatible living donor liver transplantation.

We report an emergency paired donor interchange living donor liver transplant performed on January 13, 2009. The 4 operations (2 liver transplants) were performed simultaneously. The aim was to avoid 2 ABO-incompatible liver transplants. One recipient in acute liver failure underwent transplantation in a high-urgency situation. The abdomen of the other recipient had severe adhesions from previous spontaneous bacterial peritonitis that rendered the recipient operation almost impossible. The ethical and logistical issues are discussed. Approaches adopted in anticipation of potential adverse outcomes are explained in view of the higher donor and recipient mortality and morbidity rates in comparison with kidney transplantation.

In situ observations of aerosol and chlorine monoxide after the 1991 eruption of mount pinatubo: effect of reactions on sulfate aerosol.

Highly resolved aerosol size distributions measured from high-altitude aircraft can be used to describe the effect of the 1991 eruption of Mount Pinatubo on the stratospheric aerosol. In some air masses, aerosol mass mixing ratios increased by factors exceeding 100 and aerosol surface area concentrations increased by factors of 30 or more. Increases in aerosol surface area concentration were accompanied by increases in chlorine monoxide at mid-latitudes when confounding factors were controlled. This observation supports the assertion that reactions occurring on the aerosol can increase the fraction of stratospheric chlorine that occurs in ozone-destroying forms.

The detection of large HNO3-containing particles in the winter Arctic stratosphere.

Large particles containing nitric acid (HNO3) were observed in the 1999/2000 Arctic winter stratosphere. These in situ observations were made over a large altitude range (16 to 21 kilometers) and horizontal extent (1800 kilometers) on several airborne sampling flights during a period of several weeks. With diameters of 10 to 20 micrometers, these sedimenting particles have significant potential to denitrify the lower stratosphere. A microphysical model of nitric acid trihydrate particles is able to simulate the growth and sedimentation of these large sizes in the lower stratosphere, but the nucleation process is not yet known. Accurate modeling of the formation of these large particles is essential for understanding Arctic denitrification and predicting future Arctic ozone abundances.

Chemical loss of ozone in the arctic polar vortex in the winter of 1991-1992.

In situ measurements of chlorine monoxide, bromine monoxide, and ozone are extrapolated globally, with the use of meteorological tracers, to infer the loss rates for ozone in the Arctic lower stratosphere during the Airborne Arctic Stratospheric Expedition II (AASE II) in the winter of 1991-1992. The analysis indicates removal of 15 to 20 percent of ambient ozone because of elevated concentrations of chlorine monoxide and bromine monoxide. Observations during AASE II define rates of removal of chlorine monoxide attributable to reaction with nitrogen dioxide (produced by photolysis of nitric acid) and to production of hydrochloric acid. Ozone loss ceased in March as concentrations of chlorine monoxide declined. Ozone losses could approach 50 percent if regeneration of nitrogen dioxide were inhibited by irreversible removal of nitrogen oxides (denitrification), as presently observed in the Antarctic, or without denitrification if inorganic chlorine concentrations were to double.

Does stress in a dental hygiene and dental therapy undergraduate programme contribute to a sense of well-being in the students?

Aims To use a qualitative approach to further explore the stress and well-being of dental hygiene and dental therapy students (DHDTS) during their undergraduate training.Subjects and methods Semi-structured individual interviews to explore motivation, goals, and perceived stress, were conducted with eight DHDTS from across all three years of study at the University of Portsmouth Dental Academy (UPDA). Thematic analysis of the data was undertaken using Braun and Clarke's (2006) six phases of thematic analysis.Results Three main themes of 'fulfilment', 'the learning environment', and 'perception of stress' were identified. Within these themes, a further 12 sub-themes were identified. Analysis suggested that a strong sense of passion to become a clinician mitigated most, but not all, of the stressful experiences of the DHDTS undergraduate learning environment.Conclusions DHDTS' perceived sources of stress during their undergraduate programme were strongly linked to a sense of meaningfulness.Listen to the author talk about the key findings in this paper in the associated video abstract. Available in the supplementary information online and on the BDJ Youtube channel via http://go.nature.com/bdjyoutube.

Perceived stress and well-being among dental hygiene and dental therapy students.

Aims To explore dental hygiene and dental therapy students' (DHDTS') perception of stress and well-being during their undergraduate education and establish base-line data for further studies of this group of dental professionals.Subjects and methods A questionnaire was distributed to Years 1, 2 and 3 DHDTS and final year outreach dental students (DS) (as a comparison group), at the University of Portsmouth Dental Academy (UPDA), during summer 2015. Data were collected on students' perception of levels of stress and well-being. Statistical analyses were undertaken using SPSS software. Mann-Whitney U tests with Bonferroni corrections were used and the level for a statistically significant difference was set at p <0.002.Results A response rate of 81% (DHDTS) and 85% (DS) was achieved. Clinical factors and academic work were perceived as stressful for both DHDTS and DS, with no significant difference between the groups. The majority of respondents reported levels of depression, anxiety, and stress to be within the normal range. All students reported high levels of positive well-being, with DHDTS scoring significantly higher than DS in the dimensions of personal growth, purpose in life, self-acceptance and positive relations with others (p <0.002).Conclusions DHDTS and DS identified sources of stress within their undergraduate education, but also perceived themselves as positively-functioning individuals.

Elevated plasma adiponectin in humans with genetically defective insulin receptors.

CONTEXT: Adiponectin has been suggested to play a role in the etiopathogenesis of at least some forms of insulin resistance, in part based on a strong correlation between plasma levels of adiponectin and measures of insulin sensitivity. OBJECTIVE: The objective of the study was to establish whether this relationship is maintained at extreme levels of insulin resistance. DESIGN/SETTING: This was a cross-sectional study in a university teaching hospital of subjects recruited from the United Kingdom and the United States. PARTICIPANTS: Participants included 75 subjects with a range of syndromes of severe insulin resistance and 872 nondiabetic controls. OUTCOME MEASURES: Fasting plasma insulin, adiponectin, and leptin were measured. RESULTS: Unexpectedly, subjects with mutations in the insulin receptor, despite having the most severe degree of insulin resistance, had elevated plasma adiponectin [median 24.4 mg/liter; range 6.6-36.6 (normal adult range for body mass index 20 kg/m(2) = 3-19 mg/liter)], whereas all other subjects had low adiponectin levels (median 2.0 mg/liter; range 0.12-11.2). Plasma leptin in all but one subject with an insulin receptoropathy was low or undetectable [median 0.5 ng/ml; range 0-16: normal adult range for body mass index of < 25 kg/m(2) = 2.4-24.4 (female) and 0.4-8.3 ng/ml (male)]. CONCLUSIONS: We conclude that the relationship between plasma adiponectin and insulin sensitivity is complex and dependent on the precise etiology of defective insulin action and that the combination of high plasma adiponectin with low leptin may have clinical utility in patients with severe insulin resistance as a marker of the presence of a genetic defect in the insulin receptor.

High prevalence of hepatitis C virus but not HIV co-infection among patients with tuberculosis in Georgia.

SETTING: Tuberculosis (TB) and hepatitis C virus (HCV) infection have emerged as major public health problems in former Soviet republics. OBJECTIVE: To determine the prevalence and risk factors for the human immunodeficiency virus (HIV) and HCV co-infection among patients with TB in Georgia, a cross-sectional study was carried out at hospitals in four Georgian cities. RESULTS: Of 272 hospitalized patients with TB, 61 (22%) were found to be HCV-seropositive and three (1%) were HIV-seropositive. The median age of those with TB was 35 years (range 18-74 years); 74% were male. In multivariate analysis, risk factors for HCV co-infection included previous incarceration (OR 4.6, 95%CI 1.9-10.8), history of receiving a tattoo (OR 2.6, 95%CI 1.2-5.7), previous diagnosis of a sexually transmitted infection (OR 7.2, 95%CI 1.4-37.8), and age 26-45 years (OR 2.1, 95%CI 1.0-4.6). CONCLUSION: HCV co-infection was common among hospitalized patients with TB in Georgia. Incarceration and receiving a tattoo, a common practice among inmates in Georgian and former Soviet correctional facilities, were important independent risk factors associated with HCV infection among those with TB. Further studies are needed to assess the impact of the high prevalence of HCV co-infection on treatment outcomes, including tolerability and risk of anti-tuberculosis drug induced hepatotoxicity.

The crystal structures of trout Hb I in the deoxy and carbonmonoxy forms.

We have determined the X-ray crystallographic structure of trout Hb I in both the deoxy and carbonmonoxy forms to resolution limits of 2.3 angstroms and 2.5 angstroms, respectively. The overall fold of the molecule is highly similar to that of human HbA despite the low level of sequence identity between these proteins. Trout Hb I is unusual in displaying almost no pH dependence of oxygen binding affinity, and (at most) very weak interactions with heterotropic effector ligands such as organic phosphates. Comparison of the two quaternary states of the protein indicates how such effects are minimised and how the low-affinity T state of the protein is stabilised in the absence of heterotropic interactions.

The structure of deoxy- and oxy-leghaemoglobin from lupin.

The leghaemoglobins have oxygen affinities 11 to 24 times higher than that of sperm whale myoglobin, due mainly to higher rates of association. To find out why, we have determined the structures of deoxy- and oxy-leghaemoglobin II of the lupin at 1.7 A resolution. Results confirm the general features found in previous X-ray analyses of this protein. The unique feature that has now emerged is the rotational freedom of the proximal histidine. In deoxy-leghaemoglobin the imidazole oscillates between two alternative orientations, eclipsing either the lines N1-N3 or N2-N4 of the porphyrin; in oxy-leghaemoglobin it is fixed in a staggered orientation. The iron atom moves from a position 0.30 A from the plane of the pyrrole nitrogen atoms in deoxy- to a position in the plane in oxy-leghaemoglobin while the Fe- bond distance remains constant at 2.02 A. The Fe-O-O angle is 152 degrees, as in human haemoglobin. The oxygen is hydrogen-bonded to the distal histidine at N epsilon 2-O1 and N epsilon 2-O2 distance of 2.95 A and 2.68 A, respectively. The porphyrin is ruffled equally in deoxy- and oxy-leghaemoglobins, due to rotations of the pyrrols about the N-Fe-N bonds, causing the methine bridges to deviate by up to 0.32 A from the mean porphyrin plane. The only feature capable of accounting for the high on-rate of the reaction with oxygen are the mobilities of the proximal histidine and distal histidine residues in deoxy-leghaemoglobin. The eclipsed positions of the proximal histidine in deoxy-leghaemoglobin maximize steric hindrance with the porphyrin nitrogen atoms and minimize pi-->p electron donation, while its staggered position in oxy-leghaemoglobin reverses both these effects. Together with the oscillation of the imidazole between the two orientations, these two factors may reduce the activation energy for the reaction of leghaemoglobin with oxygen. The distal histidine is in a fixed position in the haem pocket in the crystal, but must be swinging in and out of the pocket at a high rate in solution to allow the oxygen to enter.

The binding of carbon monoxide and nitric oxide to leghaemoglobin in comparison with other haemoglobins.

Haemoglobins have the ability to discriminate between oxygen and other diatomic molecules. To further understanding of this process the X-ray crystal structures of carbonmonoxy and nitrosyl-leghaemoglobin have been determined at 1.8 A resolution. The ligand geometry is discussed in detail and the controversial issue of bent versus linear carbon monoxide binding is addressed. The bond angle of 160 degrees for CO-leghaemoglobin is in conflict with recent spectroscopy results on myoglobin but is consistent with angles obtained for myoglobin X-ray crystal structures. In contrast to the numerous carbon monoxide studies, very little stereochemical information is available for the nitric oxide adduct of haemoglobin. This is provided by the X-ray structure of NO-leghaemoglobin, which conforms to expected geometry with an Fe-NO angle of 147 degrees and a lengthened iron-proximal histidine bond. Thus crystallographic evidence is given for the predicted weakening of this bond on the binding of nitric oxide.

Crystal structure of vipoxin at 2.0 A: an example of regulation of a toxic function generated by molecular evolution.

Vipoxin is the main toxic component in the venom of the Bulgarian snake Vipera ammodytes meridionalis, the most toxic snake in Europe. Vipoxin is a complex between a toxic phospholipase A2 (PLA2) and a non-toxic protein inhibitor. The structure is of genetic interest due to the high degree of sequence homology (62%) between the two functionally different components. The structure shows that the formation of the complex in vipoxin is significantly different to that seen in many known structures of phospholipases and contradicts the assumptions made in earlier studies. The modulation of PLA2 activity is of great pharmacological interest, and the present structure will be a model for structure-based drug design.

Recent strategies in the search for new anti-influenza therapies.

Influenza is a highly contagious, acute upper respiratory tract disease caused by influenza virus, a member of the Orthomyxoviridae family. The viral particles have two surface antigens, haemagglutinin and sialidase (neuraminidase) that extensively decorate the surface of the virus and have been implicated in viral attachment and fusion, and the release of virion progeny, respectively. The receptor for haemagglutinin is the terminal sialic acid residue of host cell surface sialyloligosaccharides, while sialidase catalyses the hydrolysis of terminal sialic acid residues from sialyloligosaccharides. Extensive crystallographic studies of both these proteins have revealed that the residues that interact with the sialic acid are strictly conserved. Therefore, these proteins make attractive targets for the design of drugs to halt the progression of the virus. Recent successful efforts in the search for new cures for influenza have led to the development of three clinically-useful anti-influenza drugs. All three are potent, selective inhibitors of influenza virus A and B sialidase. Strategies for the development of haemagglutinin inhibitors have also been devised.

Investigation of the stability of thiosialosides toward hydrolysis by sialidases using NMR spectroscopy.

[formula: see text] 1H NMR spectroscopy has been used to investigate whether the alpha(2-->6)-linked thiosialoside 3 and the alpha(2-->3)-linked thiosialoside 9 are hydrolyzed in the presence of Vibrio cholerae sialidase. Similarly, the hydrolysis of the O-ketosides Neu5Ac-2-O-alpha-(2-->3)-Gal beta Me (4) and the alpha-(2-->6)-sialyllactoside 7, representing natural alpha(2-->3)- and alpha(2-->6)-linked sialosides, respectively, was investigated. The results of the 1H NMR experiments clearly demonstrate that the thiosialosides are not hydrolyzed by Vibrio cholerae sialidase. As expected, the O-sialosides are hydrolyzed to give N-acetyl-alpha-D-neuraminic acid as the first product of substrate cleavage.

Premature rupture of membranes prior to term: consequences of nonintervention.

Consequences of nonintervention in the management of prematurely ruptured membranes prior to term were assessed in 143 maternal charts and 145 corresponding infant records during a 2-year period. Patients were hospitalized at bed rest and were not given tocolytics or steroids. Antibiotics were used only when clinical examination indicated infection. Labor was induced in 13 patients. Time in utero was extended 1 week or more in 19% of cases. Maternal infection was identified in 15 women, all of whom recovered. There were 18 neonatal deaths and 4 stillbirths in the series. Three deaths might have been prevented by earlier delivery. Nonintervention in the management of premature rupture of the membranes did not have adverse effects on the incidence of maternal or neonatal infection but was relatively ineffectual in achieving significant extensions of time in utero

Effects of parathyroid extract on the rupture strength of intact skin of the rat.

Rats were injected with parathyroid extract (PTE) to search for possible effects on connective tissue of the skin. Rupture strength analysis of skin samples showed a significant increase in strength of skin from PTE-treated rats. The explanation for this effect is not understood at present.

Children's recall 1 or 2 years after an event.

In Study 1, children were reinterviewed about an event they had taken part in 2 years earlier when they were 6 years old (M.-E. Pipe & J. C. Wilson, 1994). In Study 2, children were reinterviewed about an event in which they had participated 1 year earlier when they were 6 or 9 years of age (S. Gee & M.-E. Pipe, 1995). Interviews were conducted with or without cue items and distractors, as in the original studies. The amount of information reported in free recall decreased over the 1- or 2-year delays, and for 6-year-olds, there was also a small decrease in accuracy of free recall. Reinstating specific cue items in Study 2 maintained recall when attention was drawn to them, but prompting children led to a decrease in accuracy. Whereas information repeated across interviews was highly accurate, information reported for the first time at the long delays was not.