Extended use of systemic steroid is beneficial in preserving hearing in guinea pigs after cochlear implant

CONCLUSION

Seven-day administration of systemic steroids was more effective in preserving hearing for 12 weeks after cochlear implantation (CI) than a 3-day delivery.

OBJECTIVES

To determine the effectiveness of extended delivery of systemic steroids to preserve hearing in guinea pigs after CI.

METHODS

Dexamethasone (4 mg/ml) was delivered parenterally via a mini-osmotic pump for either 3 or 7 days. A dummy CI electrode was inserted via cochleostomy approach in 8-week-old guinea pigs. Auditory thresholds were assessed from tone burst auditory brainstem responses (2, 8, 16, 24, and 32 kHz) at 1 day prior to CI, and 1, 4, and 12 weeks after implantation. Histologic evaluation of the cochleae was carried out.

RESULTS

No differences were observed in hearing thresholds among groups before CI. Significant hearing preservation was achieved at 8, 16, 24, and 32 kHz only in the 7-day infusion group compared with the control group at 1 week after CI. The same trend was maintained at 4 weeks (16, 24 kHz) and 12 weeks (16, 24, and 32 kHz). Histologic review of the 7-day infusion group revealed less fibrosis and ossification in the scala tympani and the preservation of more spiral ganglion cells, compared with the control group.

How should we best estimate the mean recency duration for the BED method?

BED estimates of HIV incidence from cross-sectional surveys are obtained by restricting, to fixed time T, the period over which incidence is estimated. The appropriate mean recency duration () then refers to the time where BED optical density (OD) is less than a pre-set cut-off C, given the patient has been HIV positive for at most time T. Five methods, tested using data for postpartum women in Zimbabwe, provided similar estimates of for C = 0.8: i) The ratio (r/s) of the number of BED-recent infections to all seroconversions over T = 365 days: 192 days [95% CI 168–216]. ii) Linear mixed modeling (LMM): 191 days [95% CI 174–208]. iii) Non-linear mixed modeling (NLMM): 196 days [95% CrI 188–204]. iv) Survival analysis (SA): 192 days [95% CI 168–216]. Graphical analysis: 193 days. NLMM estimates of - based on a biologically more appropriate functional relationship than LMM – resulted in best fits to OD data, the smallest variance in estimates of , and best correspondence between BED and follow-up estimates of HIV incidence, for the same subjects over the same time period. SA and NLMM produced very similar estimates of but the coefficient of variation of the former was >3 times as high. The r/s method requires uniformly distributed seroconversion events but is useful if data are available only from a single follow-up. The graphical method produces the most variable results, involves unsound methodology and should not be used to provide estimates of . False-recent rates increased as a quadratic function of C: for incidence estimation C should thus be chosen as small as possible, consistent with an adequate resultant number of recent cases, and accurate estimation of . Inaccuracies in the estimation of should not now provide an impediment to incidence estimation.

An enzyme-initiated Smiles rearrangement enables the development of an assay of MshB, the GlcNAc-Ins deacetylase of mycothiol biosynthesis

MshB is the N-acetyl-1-D-myo-inosityl-2-amino-2-deoxy-D-glucopyranoside (GlcNAc-Ins) deacetylase active as one of the enzymes involved in the biosynthesis of mycothiol (MSH), a protective low molecular weight thiol present only in Mycobacterium tuberculosis and other actinomycetes. In this study, structural analogues of GlcNAc-Ins in which the inosityl moiety is replaced by a chromophore were synthesized and evaluated as alternate substrates of MshB, with the goal of identifying a compound that would be useful in high-throughput assays of the enzyme. In an unexpected and surprising finding one of the GlcNAc-Ins analogues is shown to undergo a Smiles rearrangement upon MshB-mediated deacetylation, uncovering a free thiol group. We demonstrate that this chemistry can be exploited for the development of the first continuous assay of MshB activity based on the detection of thiol formation by DTNB (Ellman's reagent); such an assay should be ideally suited for the identification of MshB inhibitors by means of high-throughput screens in microplates.

Systemic immunity influences hearing preservation in cochlear implantation

HYPOTHESIS

To determine whether a systemic immune response influences hearing thresholds and tissue response after cochlear implantation of hearing guinea pigs.

METHODS

Guinea pigs were inoculated with sterile antigen (Keyhole limpet hemocyanin) 3 weeks before cochlear implantation. Pure-tone auditory brainstem response thresholds were performed before implantation and 1 and 4 weeks later. Dexamethasone phosphate 20% was adsorbed onto a hyaluronic acid carboxymethylcellulose sponge and was applied to the round window for 30 minutes before electrode insertion. Normal saline was used for controls. Cochlear histology was performed at 4 weeks after implantation to assess the tissue response to implantation. To control for the effect of keyhole limpet hemocyanin priming, a group of unprimed animals underwent cochlear implantation with a saline-soaked pledget applied to the round window.

RESULTS

Keyhole limpet hemocyanin priming had no significant detrimental effect on thresholds without implantation. Thresholds were elevated after implantation across all frequencies tested (2-32 kHz) in primed animals but only at higher frequencies (4-32 kHz) in unprimed controls. In primed animals, dexamethasone treatment significantly reduced threshold shifts at 2 and 8 kHz. Keyhole limpet hemocyanin led to the more frequent observation of lymphocytes in the tissue response to the implant.

CONCLUSION

Systemic immune activation at the time of cochlear implantation broadened the range of frequencies experiencing elevated thresholds after implantation. Local dexamethasone provides partial protection against this hearing loss, but the degree and extent of protection are less compared to previous studies with unprimed animals.

BED estimates of HIV incidence: resolving the differences, making things simpler

OBJECTIVE

Develop a simple method for optimal estimation of HIV incidence using the BED capture enzyme immunoassay.

DESIGN

Use existing BED data to estimate mean recency duration, false recency rates and HIV incidence with reference to a fixed time period, T.

METHODS

Compare BED and cohort estimates of incidence referring to identical time frames. Generalize this approach to suggest a method for estimating HIV incidence from any cross-sectional survey.

RESULTS

Follow-up and BED analyses of the same, initially HIV negative, cases followed over the same set time period T, produce estimates of the same HIV incidence, permitting the estimation of the BED mean recency period for cases who have been HIV positive for less than T. Follow-up of HIV positive cases over T, similarly, provides estimates of the false-recent rate appropriate for T. Knowledge of these two parameters for a given population allows the estimation of HIV incidence during T by applying the BED method to samples from cross-sectional surveys. An algorithm is derived for providing these estimates, adjusted for the false-recent rate. The resulting estimator is identical to one derived independently using a more formal mathematical analysis. Adjustments improve the accuracy of HIV incidence estimates. Negative incidence estimates result from the use of inappropriate estimates of the false-recent rate and/or from sampling error, not from any error in the adjustment procedure.

CONCLUSIONS

Referring all estimates of mean recency periods, false-recent rates and incidence estimates to a fixed period T simplifies estimation procedures and allows the development of a consistent method for producing adjusted estimates of HIV incidence of improved accuracy. Unadjusted BED estimates of incidence, based on life-time recency periods, would be both extremely difficult to produce and of doubtful value.

Round window delivery of dexamethasone ameliorates local and remote hearing loss produced by cochlear implantation into the second turn of the guinea pig cochlea

Application of dexamethasone to the round window has been shown to ameliorate high frequency hearing loss resulting from the trauma of cochlear implantation in experimental animals, but elucidation of the factors influencing protection of the high frequencies has been confounded by the local trauma from electrode array insertion. In this experiment, a second turn cochleostomy and implantation was performed on guinea pigs, to examine protection in the basal turn without the confounding effect of local trauma, as well as to test the efficacy of hearing protection in the second cochlear turn. The implantation resulted in an increase in hearing thresholds across all frequencies examined (2-32 kHz). Local delivery of dexamethasone to the round window prior to implantation protected hearing across frequencies from 2 to 32 kHz. Auditory thresholds improved over the first week after surgery, and then remained stable for the month of the experiment. The protection of hearing in the basal turn increased with longer periods of drug application prior to implantation. The level of hearing protection in the second turn was similar irrespective of the time that the drug was applied, but was greater when a higher steroid concentration was used. It was concluded that steroids protect hearing in the basal turn of the cochlea even when there was no local trauma. The level of hearing protection in the second turn exceeded that expected from models of steroid diffusion through the cochlea, suggesting that inner ear surgery alters the distribution of dexamethasone within the cochlea.

Binding a heparin derived disaccharide to defensin inspired peptides: insights to antimicrobial inhibition from gas-phase measurements

Due to the ubiquitous presence of polysaccharide moieties on bacterial surfaces, it is hypothesised that a peptide-saccharide interaction plays a key role during the recognition of invading microorganisms by beta-defensins. We have employed different gas-phase methods to investigate these interactions. This manuscript describes: an MS-based titration assay measuring the gas-phase binding of ten beta-defensin related peptides to a sulfated disaccharide derived from heparin (HDD); ion mobility-mass spectrometry-determined collision cross sections of 3 peptides (both free and binding HDD); and results from molecular modelling with the aim of reconciling some of our experimental observations. We observe a clear qualitative correlation between the antimicrobial activity of several beta-defensins and related peptides and their gas-phase binding to a heparin-derived disaccharide (HDD). Four of the ten peptides show >100 micromolar K(d) values with HDD, and no bacteriocidal activity, illustrating that HDD binding correlates with peptide antimicrobial activity. For five of the remaining six peptides, bacteriocidal activity was re-measured with HDD present. For the peptides containing intramolecular disulfide bonds in two out of five, bacteriocidal activity was reduced approximately 10-fold; for the remaining three peptides, which lack intramolecular disulfide bonds, HDD addition had little effect on bacteriocidal activity. The latter results are suggested to arise from the greater degree of flexibility imparted by the removal of disulfide bonds giving the peptides the ability to envelope HDD and assume a "defensin-like" fold. Thus gas-phase analysis is put forward as a powerful tool for assessing the properties of antimicrobial peptides providing valuable insights in the mechanism of antimicrobial inhibition.

Development of an ion mobility quadrupole time of flight mass spectrometer

We describe here a new ion mobility capable mass spectrometer which comprises a drift cell for mobility separation and a quadrapole time of flight mass spectrometer for mass analysis--the MoQTOF. A commercial QToF instrument (Micromass UK Ltd., Manchester, UK) has been modified by the inclusion of an additional chamber containing a drift cell and ancillary ion optics. The drift cell is 5.1 cm long made from a copper block and is mounted from a top hat flange in a chamber situated post source optics and prior to the quadapole analyzer. Details of this instrument are provided along with information about how it can be used to acquire mobilities of ions along with their mass to charge ratios. The MoQTOF is used to examine conformations of a series of antimicrobial peptides based on a beta-defensin template. In vivo, these cationic cystine-rich amphiphilic peptides are conformationally restrained by three or more disulfide bridges, although recent findings by several groups have cast doubt on the importance of canonical disulfide pairing to antimicrobial activities. By synthesizing a panel of variants to Defb14 (the murine orthologue of HBD3), we exploit ion mobility to distinguish conformational differences which arise due to disulfide formation and to the hydrophobicity of the peptide sequence. Our gas-phase results are interpreted in terms of the antimicrobial and chemotacic properties of beta-defensins, and this mass spectrometry based approach to discern structure may have a role in future design of novel antibiotics.

Cellular redox regulation and prooxidant signaling systems: a new perspective on the free radical theory of aging

The overarching role of coenzyme Q(10) in gene regulation, bioenergy formation, cellular redox poise regulation, and hydrogen peroxide formation is presented. Coenzyme Q(10) has a central role acting as a prooxidant in the generation of H(2)O(2). Contrary to the dogma that superoxide and H(2)O(2) formation are highly deleterious to cell survival this premise is rejected. Data are discussed that continuous superoxide and hydrogen peroxide formation are essential for normal cell function and that they play a major role in subcellular redox state modulation. It is the prooxidant activity of the so-called antioxidants that may be responsible for previously claimed benefits for high doses of oxido-reduction nutritional supplements such as alpha lipoic acid and coenzyme Q(10). Oxygen-free radical formation is essential for the biological function and is not a direct causation of the mammalian aging process; aging is a multisystem stochastic process.

β-Defensin evolution: selection complexity and clues for residues of functional importance

We have examined the evolution of the genes at the major human beta-defensin locus and the orthologous loci in a range of other primates and mammals. For the first time, these data allow us to examine selective episodes in the more recent evolutionary history of this locus as well as in the ancient past. We have used a combination of maximum-likelihood-based tests and a maximum-parsimony-based sliding window approach to give a detailed view of the varying modes of selection operating at this locus. We provide evidence for strong positive selection soon after the duplication of these genes within an ancestral mammalian genome. During the divergence of primates, however, variable selective pressures have acted on beta-defensin genes in different evolutionary lineages, with episodes of both negative and, more rarely, positive selection. Positive selection appears to have been more common in the rodent lineage, accompanying the birth of novel rodent-specific beta-defensin gene clades. Sites in the second exon have been subject to positive selection and, by implication, are important in functional diversity. A small number of sites in the mature human peptides were found to have undergone repeated episodes of selection in different primate lineages. Particular sites were consistently implicated by multiple methods at positions throughout the mature peptides. These sites are clustered at positions that are predicted to be important for the function of beta-defensins.

The complexity of selection at the major primate beta-defensin locus

BACKGROUND

We have examined the evolution of the genes at the major human beta-defensin locus and the orthologous loci in a range of other primates and mouse. For the first time these data allow us to examine selective episodes in the more recent evolutionary history of this locus as well as the ancient past. We have used a combination of maximum likelihood based tests and a maximum parsimony based sliding window approach to give a detailed view of the varying modes of selection operating at this locus.

RESULTS

We provide evidence for strong positive selection soon after the duplication of these genes within an ancestral mammalian genome. Consequently variable selective pressures have acted on beta-defensin genes in different evolutionary lineages, with episodes both of negative, and more rarely positive selection, during the divergence of primates. Positive selection appears to have been more common in the rodent lineage, accompanying the birth of novel, rodent-specific beta-defensin genes. These observations allow a fuller understanding of the evolution of mammalian innate immunity. In both the rodent and primate lineages, sites in the second exon have been subject to positive selection and by implication are important in functional diversity. A small number of sites in the mature human peptides were found to have undergone repeated episodes of selection in different primate lineages. Particular sites were consistently implicated by multiple methods at positions throughout the mature peptides. These sites are clustered at positions predicted to be important for the specificity of the antimicrobial or chemoattractant properties of beta-defensins. Surprisingly, sites within the prepropeptide region were also implicated as being subject to significant positive selection, suggesting previously unappreciated functional significance for this region.

CONCLUSIONS

Identification of these putatively functional sites has important implications for our understanding of beta-defensin function and for novel antibiotic design.

Single nucleotide polymorphisms in the leptin receptor gene: studies in anorexia nervosa

Anorexia nervosa is an eating disorder of unknown aetiology. There is significant evidence for a genetic component in the pathogenesis of this disorder. A region on chromosome 1 has been identified as a susceptibility locus. The leptin receptor has been mapped to a similar region, further upstream of this susceptibility locus. Leptin and its receptor are known to be important factors in the control and regulation of body weight. Single nucleotide polymorphisms (SNPs) in the leptin receptor are associated with measures of body weight. In the present study, SNPs in the coding region of the leptin receptor were analysed and their possible association with anorexia nervosa was investigated. Two cohorts of young women, 176 Caucasian anorexia nervosa patients and 152 normal Caucasian females, were genotyped for three SNPs in the leptin receptor. There was no significant difference in allele or genotype frequency, for any SNP, between the normal controls and the cohort of anorexia subjects. There were no significant associations with any genotype and body mass index in either the control or anorexic cohorts. When the anorexic cohort was subdivided into restricting and bingeing/purging behaviours, we found no significant association with any genotype. Analysis of haplotypes showed no significant evidence of association with anorexia. In summary, leptin receptor SNPs do not appear to be important factors in the regulation of body weight in young, pre-menopausal women or have any significant association with anorexia nervosa.

Cellular redox poise modulation; the role of coenzyme Q10, gene and metabolic regulation

In this communication, the concept is developed that coenzyme Q10 has a toti-potent role in the regulation of cellular metabolism. The redox function of coenzyme Q10 leads to a number of outcomes with major impacts on sub-cellular metabolism and gene regulation. Coenzyme Q10's regulatory activities are achieved in part, through the agency of its localization in the various sub-cellular membrane compartments. Its fluctuating redox poise within these membranes reflects the cell's metabolic micro-environments. As an integral part of this process, H2O2 is generated as a product of the normal electron transport systems to function as a mitogenic second messenger informing the nuclear and mitochondrial (chloroplast) genomes on a real-time basis of the status of the sub-cellular metabolic micro-environments and the needs of that cell. Coenzyme Q10 plays a major role both in energy conservation, and energy dissipation as a component of the uncoupler protein family. Coenzyme Q10 is both an anti-oxidant and a pro-oxidant and of the two the latter is proposed as its more important cellular function. Coenzyme Q10 has been reported, to be of therapeutic benefit in the treatment of a wide range of age related degenerative systemic diseases and mitochondrial disease. Our over-arching hypotheses on the central role played by coenzyme Q10 in redox poise changes, the generation of H2O2, consequent gene regulation and metabolic flux control may account for the wide ranging therapeutic benefits attributed to coenzyme Q10.

A qualitative study of Australian GPs' attitudes and practices in the diagnosis and management of attention-deficit/hyperactivity disorder (ADHD)

BACKGROUND

The importance of general practice involvement in the care of attention-deficit/ hyperactivity disorder (ADHD) is increasing due to the rising numbers of patients who present with the disorder. It has been suggested by consensus bodies that GPs should be identifying and referring patients at the severe end of the ADHD spectrum and managing those with less severe symptoms. However, GPs' views of their role in ADHD care are unknown.

OBJECTIVE

Our aim was to explore the attitudes and practices of Australian GPs towards the diagnosis and management of ADHD.

METHODS

We conducted a series of focus groups to explore GPs' beliefs regarding the causes of ADHD, their perceived role in ADHD diagnosis and management and their views on the role of behaviour therapies and pharmacotherapies in ADHD management. The subjects were 28 GPs in six focus groups.

RESULTS

GPs in this study did not want to be the primary providers of care for patients with ADHD. Participants indicated a preference to refer the patient to medical specialists for diagnosis and treatment of ADHD, and expressed low levels of interest in becoming highly involved in ADHD care. Concerns about overdiagnosis and misdiagnosis of the disorder, diagnostic complexity, time constraints, insufficient education and training about the disorder, and concerns regarding misuse and diversion of stimulant medications were the reasons cited for their lack of willingness.

CONCLUSIONS

The Australian GPs in this study identify a role for themselves in ADHD care which is largely supportive in nature, and involves close liaison with specialist services.

The proteomics of ageing

Proteomics provides an extremely powerful tool for the study of variations in protein expression between individuals, different disease states and different conditions. One of the major challenges facing the medical profession in the forthcoming decades is to understand the changes that occur in individuals as they become older and to attempt to develop means to improve the quality of life for the otherwise healthy ageing population. The present study describes the first phase of such an investigation in which the protein composition of human skeletal muscle samples from young and aged subjects are compared. These results provide the beginning of a Human Aged Skeletal Muscle Profile reference map which is an essential first step to further investigations.

Variation in the ESR1 and ESR2 genes and genetic susceptibility to anorexia nervosa

There is significant evidence for genetic factors in the susceptibility to anorexia nervosa (AN). Previously genetic variation in the estrogen receptor 2 gene (ESR2) has been studied, however no strong evidence of association with AN has been found. In the present study variation in the estrogen receptor 1 (ESR1) and ESR2 genes was examined. Estrogen receptors have been localised to areas of the brain involved in behaviour and regulation of food intake. The anorexic effects of estrogen are accentuated by stress and thus it is postulated that variation in the estrogen receptors may contribute to the genetic susceptibility to AN in females. A cohort of 170 female, Caucasian AN sufferers and 152 female controls were typed for dinucleotide repeat polymorphisms in both ESR1 and ESR2 and two further SNPs at each locus. Variation at ESR1 was not associated with AN. However an association was found at the ESR2 locus with the heterozygous genotype of the G1082A polymorphism and AN but not with any of the other ESR2 polymorphisms analysed. Analysis of haplotypes at ESR1 and ESR2 showed no significant evidence of association with AN suggesting that the variability in ESR2 alone may contribute to the genetic susceptibility to AN.

Human aging and global function of coenzyme Q10

In this paper, we review two parts of our recent work on human skeletal muscle. The first part mainly describes changes occurring during aging, whereas the second part discusses the functions of coenzyme Q10 (CoQ10), particularly in relation to the aging process. During the lifetime of an individual, mtDNA undergoes a variety of mutation events and rearrangements. These mutations and their consequent bioenergenic decline, together with nuclear DNA damage, contribute to the reduced function of cells and organs, especially in postmitotic tissues. In skeletal muscle, this functional decline can be observed by means of changes with age in fiber type profile and the reduction in the number and size of the muscle fibers. In addition to the functions of coenzyme Q10 as an electron carrier in the respiratory chain and as an antioxidant, CoQ10 has been shown to regulate global gene expression in skeletal muscle. We hypothesize that this regulation is achieved via superoxide formation with H2O2 as a second messenger to the nucleus.

Cellular redox activity of coenzyme Q10: effect of CoQ10 supplementation on human skeletal muscle

In this paper, we report results obtained from a continuing clinical trial on the effect of coenzyme Q10 (CoQ10) administration on human vastus lateralis (quadriceps) skeletal muscle. Muscle samples, obtained from aged individuals receiving placebo or CoQ10 supplementation (300mg per day for four weeks prior to hip replacement surgery) were analysed for changes in gene and protein expression and in muscle fibre type composition. Microarray analysis (Affymetrix U95A human oligonucleotide array) using a change in gene expression of 1.8-fold or greater as a cutoff point, demonstrated that a total of 115 genes were differentially expressed in six subject comparisons. In the CoQ10-treated subjects, 47 genes were up-regulated and 68 down-regulated in comparison with placebo-treated subjects. Restriction fragment differential display analysis showed that over 600 fragments were differentially expressed using a 2.0-fold or greater change in expression as a cutoff point. Proteome analysis revealed that, of the high abundance muscle proteins detected (2,086 +/- 115), the expression of 174 proteins was induced by CoQ10 while 77 proteins were repressed by CoQ10 supplementation. Muscle fibre types were also affected by CoQ10 treatment; CoQ10-treated individuals showed a lower proportion of type I (slow twitch) fibres and a higher proportion of type IIb (fast twitch) fibres, compared to age-matched placebo-treated subjects. The data suggests that CoQ10 treatment can act to influence the fibre type composition towards the fibre type profile generally found in younger individuals. Our results led us to the conclusion that coenzyme Q10 is a gene regulator and consequently has wide-ranging effects on over-all tissue metabolism. We develop a comprehensive hypothesis that CoQ10 plays a major role in the determination of membrane potential of many, if not all, sub-cellular membrane systems and that H2O2 arising from the activities of CoQ10 acts as a second messenger for the modulation of gene expression and cellular metabolism.

Re-evaluation of two simple prognostic scores of outcome after proximal femoral fractures

The Belfast and Newcastle simple prognostic scores of outcome after treatment of proximal femoral fractures were recorded shortly after admission on 250 patients. All patients were then followed until discharge, with 87 of those who were the more physically and socially dependent before admission being transferred after surgery for rehabilitation in a geriatric unit. The hospital mortality rate, a hospital stay of over 6 weeks and two measures of rehabilitation outcome, i.e. a delay of over 3 weeks after the operation in regaining independent mobility and any functional decline on discharge compared with the preadmission situation, were recorded for each patient. The prediction of a higher hospital mortality rate and a delay in reaching independent mobility in more dependent patients with both scores reached statistical significance. Longer hospital stays in the more dependent patients did not occur in a situation where care facilities for dependent patients were readily available. The scores, in particular the Belfast score, can be used to compare the casemix of patients with proximal femoral fractures within and between units over time and can predict mortality and delay in achieving independent mobility. They may be helpful in the early selection of patients for transfer to a geriatric unit or orthogeriatric unit for rehabilitation.

A comparison of the psychosocial aspects of AIDS and cancer-related bereavement

OBJECTIVE

This study compares the psychological symptoms and bereavement distress of individuals bereaved by AIDS with a group bereaved by a cancer death, and addresses the question of whether an AIDS death is associated with a higher rate of adverse psychosocial factors that may increase risk of psychological morbidity in the bereaved individuals.

METHOD

AIDS (n = 28) and cancer (n = 30) bereaved individuals (all within 3 months of the bereavement) completed measures of psychological morbidity and measures addressing a range of other adverse factors, e.g., number of losses, levels of social support and stigma.

RESULTS

The cancer and AIDS bereaved were essentially similar on all psychological symptom measures. The AIDS group reported lower levels of social support in response to the bereavement than cancer bereaved individuals; a greater number of bereavements, were more likely to conceal the cause of death from significant others including their own family and perceived, in some instances, a greater level of rejection from others. The AIDS group reported higher levels of social support from friends than from family.

CONCLUSIONS

At three months following bereavement, AIDS and cancer bereaved were similar in levels of distress. While this may change with the progress of grief over time, it suggests essentially similar early bereavement responses. Those bereaved by AIDS reported a range of other adverse factors such as a greater number of losses, lower social support, stigma, and less open disclosure of the cause of death.

Pain and its control in patients with fractures of the femoral neck while awaiting surgery

A survey, by two methods, of the pain felt preoperatively by 100 elderly patients with an acute fracture of the femoral neck showed that most felt a great deal of pain and that a painless fracture was exceptional. No relationship was found between pain appreciation and the patient's fracture type or their age. One of the methods suggested that elderly patients with preserved mental function felt more pain, and the other that less pain was felt by those taking regular prefracture analgesia. The amount of analgesic drugs given to the patients in this survey seemed inadequate for their levels of perceived pain; accordingly regular measurement by nurses of the degree of pain felt preoperatively by patients with this condition is recommended, together with a greater medical review of the medication being prescribed.

Detrusor hyperreflexia--are there two types?

The concept that elderly patients with urinary incontinence due to detrusor hyperreflexia can be divided into two groups with differing natural histories on the basis of the detrusor contractility found on cystometry is reassessed. Thirty patients shown to have hyperreflexia on urodynamic study for persistent urinary incontinence following a recent neurological lesion had their contractility measured by the suggested criteria of the residual urine following a hyperreflexic contraction and the rate of increase of detrusor pressure. The consistency of contractility on cystometry was also measured by repeating this three times on the same occasion. A spectrum of values for the post-contraction volumes and the rate of increase of detrusor pressure was found. On repetitive cystometry 11 out of 30 patients showed a variable post-contraction residual volume. While impaired contractility is common in detrusor hyperreflexia, the concept of two subgroups is not supported by these results. In some patients cystometric measures of contractility vary considerably on repeating the study on the same occasion.

Proximal femoral fractures in the elderly: does operative delay for medical reasons affect short-term outcome?

Forty patients over 65 years of age with fractures of the proximal femur, whose operation was delayed more than 24 hours after admission for medical reasons, were studied. Length of post-operative stay on the orthopaedic wards, mobility after one month and need for continuing supervision by the geriatric services, after discharge from the orthopaedic wards, were compared with a matched group in whom there was no delay. There were no significant differences between the results of the two groups, suggesting that, if medical conditions are adequately treated before operative fixation of fractures of the proximal femur in elderly patients, the short-term outcome is not adversely affected.