Molecular discoveries in microbial DMSP synthesis

Dimethylsulfoniopropionate (DMSP) is one of the Earth's most abundant organosulfur compounds because many marine algae, bacteria, corals and some plants produce it to high mM intracellular concentrations. In these organisms, DMSP acts an anti-stress molecule with purported roles to protect against salinity, temperature, oxidative stress and hydrostatic pressure, amongst many other reported functions. However, DMSP is best known for being a major precursor of the climate-active gases and signalling molecules dimethylsulfide (DMS), methanethiol (MeSH) and, potentially, methane, through microbial DMSP catabolism. DMSP catabolism has been extensively studied and the microbes, pathways and enzymes involved have largely been elucidated through the application of molecular research over the last 17 years. In contrast, the molecular biology of DMSP synthesis is a much newer field, with the first DMSP synthesis enzymes only being identified in the last 5 years. In this review, we discuss how the elucidation of key DMSP synthesis enzymes has greatly expanded our knowledge of the diversity of DMSP-producing organisms, the pathways used, and what environmental factors regulate production, as well as to inform on the physiological roles of DMSP. Importantly, the identification of key DMSP synthesis enzymes in the major groups of DMSP producers has allowed scientists to study the distribution and predict the importance of different DMSP-producing organisms to global DMSP production in diverse marine and sediment environments. Finally, we highlight key challenges for future molecular research into DMSP synthesis that need addressing to better understand the cycling of this important marine organosulfur compound, and its magnitude in the environment.

Bacterial Dimethylsulfoniopropionate Biosynthesis in the East China Sea

Dimethylsulfoniopropionate (DMSP) is one of Earth's most abundant organosulfur molecules. Recently, many marine heterotrophic bacteria were shown to produce DMSP, but few studies have combined culture-dependent and independent techniques to study their abundance, distribution, diversity and activity in seawater or sediment environments. Here we investigate bacterial DMSP production potential in East China Sea (ECS) samples. Total DMSP (DMSPt) concentration in ECS seawater was highest in surface waters (SW) where phytoplankton were most abundant, and it decreased with depth to near bottom waters. However, the percentage of DMSPt mainly apportioned to bacteria increased from the surface to the near bottom water. The highest DMSP concentration was detected in ECS oxic surface sediment (OSS) where phytoplankton were not abundant. Bacteria with the genetic potential to produce DMSP and relevant biosynthesis gene transcripts were prominent in all ECS seawater and sediment samples. Their abundance also increased with depth and was highest in the OSS samples. Microbial enrichments for DMSP-producing bacteria from sediment and seawater identified many novel taxonomic groups of DMSP-producing bacteria. Different profiles of DMSP-producing bacteria existed between seawater and sediment samples and there are still novel DMSP-producing bacterial groups to be discovered in these environments. This study shows that heterotrophic bacteria significantly contribute to the marine DMSP pool and that their contribution increases with water depth and is highest in seabed surface sediment where DMSP catabolic potential is lowest. Furthermore, distinct bacterial groups likely produce DMSP in seawater and sediment samples, and many novel producing taxa exist, especially in the sediment.

Syncope in a 14yo female with ventricular tachycardia; an atypical etiology

Wide complex tachycardias are rare in the pediatric population and may be due to ventricular tachycardia, aberrant conduction or antidromic tachycardia each with multiple underlying etiologies. We present a 14 yo female in extremis with syncope at rest witnessed by her mother, found in ventricular tachycardia by EMS who challenged with IVF hydration and amiodarone. Consecutive adequate fluid challenges and antiarrhythmics in the emergency department failed requiring synchronized cardioversion for stabilization. Subsequent viral panels, imaging, genetic testing and cardiac biopsy confirmed a diagnosis of arrhythmogenic right (and left) ventricular dysplasia.

Bacteria are important dimethylsulfoniopropionate producers in marine aphotic and high-pressure environments

Dimethylsulfoniopropionate (DMSP) is an important marine osmolyte. Aphotic environments are only recently being considered as potential contributors to global DMSP production. Here, our Mariana Trench study reveals a typical seawater DMSP/dimethylsulfide (DMS) profile, with highest concentrations in the euphotic zone and decreased but consistent levels below. The genetic potential for bacterial DMSP synthesis via the dsyB gene and its transcription is greater in the deep ocean, and is highest in the sediment.s DMSP catabolic potential is present throughout the trench waters, but is less prominent below 8000 m, perhaps indicating a preference to store DMSP in the deep for stress protection. Deep ocean bacterial isolates show enhanced DMSP production under increased hydrostatic pressure. Furthermore, bacterial dsyB mutants are less tolerant of deep ocean pressures than wild-type strains. Thus, we propose a physiological function for DMSP in hydrostatic pressure protection, and that bacteria are key DMSP producers in deep seawater and sediment.

Dimethylsulfoniopropionate (DMSP) is an osmolyte produced by marine microbes that plays an important role in nutrient cycling and atmospheric chemistry. Here the authors go to the Mariana Trench—the deepest point in the ocean—and find bacteria are key DMSP producers, and that DMSP has a role in protection against high pressure.

Publisher Correction: Marine microbiology: A day in the life of marine sulfonates

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Bacteria are important dimethylsulfoniopropionate producers in coastal sediments

Dimethylsulfoniopropionate (DMSP) and its catabolite dimethyl sulfide (DMS) are key marine nutrients^1,2 that have roles in global sulfur cycling², atmospheric chemistry³, signalling^4,5 and, potentially, climate regulation^6,7. The production of DMSP was previously thought to be an oxic and photic process that is mainly confined to the surface oceans. However, here we show that DMSP concentrations and/or rates of DMSP and DMS synthesis are higher in surface sediment from, for example, saltmarsh ponds, estuaries and the deep ocean than in the overlying seawater. A quarter of bacterial strains isolated from saltmarsh sediment produced DMSP (up to 73 mM), and we identified several previously unknown producers of DMSP. Most DMSP-producing isolates contained dsyB⁸, but some alphaproteobacteria, gammaproteobacteria and actinobacteria used a methionine methylation pathway independent of DsyB that was previously only associated with higher plants. These bacteria contained a methionine methyltransferase gene (mmtN)-a marker for bacterial synthesis of DMSP through this pathway. DMSP-producing bacteria and their dsyB and/or mmtN transcripts were present in all of the tested seawater samples and Tara Oceans bacterioplankton datasets, but were much more abundant in marine surface sediment. Approximately 1 × 10⁸ bacteria g^-1 of surface marine sediment are predicted to produce DMSP, and their contribution to this process should be included in future models of global DMSP production. We propose that coastal and marine sediments, which cover a large part of the Earth's surface, are environments with high levels of DMSP and DMS productivity, and that bacteria are important producers of DMSP and DMS within these environments.

Author Correction: DSYB catalyses the key step of dimethylsulfoniopropionate biosynthesis in many phytoplankton

In the version of this Letter originally published, the Methods incorrectly stated that all phytoplankton cultures were sampled in mid-exponential phase. The low-nitrogen cultures were sampled in early stationary phase and at the point at which Fv/Fm values decreased, to indicate that cultures were experiencing low-nitrogen conditions. All other phytoplankton cultures were sampled in exponential phase. Growth and Fv/Fm data are provided here on high- and low-nitrogen cultures (Figs 1, 2 and 3) to clarify and support this correction. The Methods also stated that cell counting was done using a Beckman Multisizer 3 Coulter Counter, but a CASY Model TT Cell Counter was used.

DSYB catalyses the key step of dimethylsulfoniopropionate biosynthesis in many phytoplankton

Dimethylsulfoniopropionate (DMSP) is a globally important organosulfur molecule and the major precursor for dimethyl sulfide. These compounds are important info-chemicals, key nutrients for marine microorganisms, and are involved in global sulfur cycling, atmospheric chemistry and cloud formation^1-3. DMSP production was thought to be confined to eukaryotes, but heterotrophic bacteria can also produce DMSP through the pathway used by most phytoplankton ⁴ , and the DsyB enzyme catalysing the key step of this pathway in bacteria was recently identified ⁵ . However, eukaryotic phytoplankton probably produce most of Earth's DMSP, yet no DMSP biosynthesis genes have been identified in any such organisms. Here we identify functional dsyB homologues, termed DSYB, in many phytoplankton and corals. DSYB is a methylthiohydroxybutryate methyltransferase enzyme localized in the chloroplasts and mitochondria of the haptophyte Prymnesium parvum, and stable isotope tracking experiments support these organelles as sites of DMSP synthesis. DSYB transcription levels increased with DMSP concentrations in different phytoplankton and were indicative of intracellular DMSP. Identification of the eukaryotic DSYB sequences, along with bacterial dsyB, provides the first molecular tools to predict the relative contributions of eukaryotes and prokaryotes to global DMSP production. Furthermore, evolutionary analysis suggests that eukaryotic DSYB originated in bacteria and was passed to eukaryotes early in their evolution.

Methanethiol-dependent dimethylsulfide production in soil environments

Dimethylsulfide (DMS) is an environmentally important trace gas with roles in sulfur cycling, signalling to higher organisms and in atmospheric chemistry. DMS is believed to be predominantly produced in marine environments via microbial degradation of the osmolyte dimethylsulfoniopropionate (DMSP). However, significant amounts of DMS are also generated from terrestrial environments, for example, peat bogs can emit ~6 μmol DMS m⁻² per day, likely via the methylation of methanethiol (MeSH). A methyltransferase enzyme termed ‘MddA’, which catalyses the methylation of MeSH, generating DMS, in a wide range of bacteria and some cyanobacteria, may mediate this process, as the mddA gene is abundant in terrestrial metagenomes. This is the first study investigating the functionality of MeSH-dependent DMS production (Mdd) in a wide range of aerobic environments. All soils and marine sediment samples tested produced DMS when incubated with MeSH. Cultivation-dependent and cultivation-independent methods were used to assess microbial community changes in response to MeSH addition in a grassland soil where 35.9% of the bacteria were predicted to contain mddA. Bacteria of the genus Methylotenera were enriched in the presence of MeSH. Furthermore, many novel Mdd⁺ bacterial strains were isolated. Despite the abundance of mddA in the grassland soil, the Mdd pathway may not be a significant source of DMS in this environment as MeSH addition was required to detect DMS at only very low conversion rates.

Teaching emotion recognition skills to young children with autism: a randomised controlled trial of an emotion training programme

BACKGROUND

Children with autism have difficulties in emotion recognition and a number of interventions have been designed to target these problems. However, few emotion training interventions have been trialled with young children with autism and co-morbid ID. This study aimed to evaluate the efficacy of an emotion training programme for a group of young children with autism with a range of intellectual ability.

METHODS

Participants were 55 children with autistic disorder, aged 4-7 years (FSIQ 42-107). Children were randomly assigned to an intervention (n = 28) or control group (n = 27). Participants in the intervention group watched a DVD designed to teach emotion recognition skills to children with autism (the Transporters), whereas the control group watched a DVD of Thomas the Tank Engine. Participants were assessed on their ability to complete basic emotion recognition tasks, mindreading and theory of mind (TOM) tasks before and after the 4-week intervention period, and at 3-month follow-up.

RESULTS

Analyses controlled for the effect of chronological age, verbal intelligence, gender and DVD viewing time on outcomes. Children in the intervention group showed improved performance in the recognition of anger compared with the control group, with few improvements maintained at 3-month follow-up. There was no generalisation of skills to TOM or social skills.

CONCLUSIONS

The Transporters programme showed limited efficacy in teaching basic emotion recognition skills to young children with autism with a lower range of cognitive ability. Improvements were limited to the recognition of expressions of anger, with poor maintenance of these skills at follow-up. These findings provide limited support for the efficacy of the Transporters programme for young children with autism of a lower cognitive range.

The relationship between emotion recognition ability and social skills in young children with autism

This study assessed the relationship between emotion recognition ability and social skills in 42 young children with autistic disorder aged 4-7 years. The analyses revealed that accuracy in recognition of sadness, but not happiness, anger or fear, was associated with higher ratings on the Vineland-II Socialization domain, above and beyond the influence of chronological age, cognitive ability and autism symptom severity. These findings extend previous research with adolescents and adults with autism spectrum disorders, suggesting that sadness recognition is also associated with social skills in children with autism.

Muromonab-CD3 (Orthoclone OKT3), methylprednisolone and cyclosporine for acute graft-versus-host disease prophylaxis in allogeneic bone marrow transplantation

We report the results of a prospective non-randomized phase II study of Muromonab-CD3 (Orthoclone OKT3), an anti-CD3 monoclonal antibody, with methylprednisolone (MP) and cyclosporine (CSA) for acute GVHD (aGVHD) prophylaxis in 22 hematologic malignancy patients. OKT3 was given at 0.1 mg/kg/day with a maximum dose of 5 mg/day. Initial MP dose was 1000 mg before OKT3, with subsequent doses at 1 mg/kg/day before each OKT3 infusion with a planned taper beginning at day +28. CSA (3 mg/kg/day) was given as a continuous infusion at day -1 and adjusted to maintain serum levels between 250 and 399 ng/ml. Allogeneic BMT donors were HLA-matched siblings (n = 17), single HLA-mismatched-related (n = 1) and HLA-matched unrelated (n = 4). All patients achieved neutrophil engraftment at a median 11 days (range, 8-25 days). By intent-to-treat, the cumulative incidence of grade II-IV aGVHD was 33% (95% CI 13-53%) at a median 26 days post-BMT (range, 14-84 days). Chronic GVHD developed in 11/12 evaluable patients. Eight patients (36%) developed OKT3 first dose reactions; no cases of post-transplant lymphoproliferative disorder were observed. OKT3 depleted peripheral CD3+ cells in vivo as measured by flow cytometry. OKT3+MP+CSA combination is moderately effective aGVHD prophylaxis, however, it is unlikely to be superior to CSA+MTX.

Effect of adding dopexamine to intraoperative volume expansion in patients undergoing major elective abdominal surgery † †This article is accompanied by the Editorial

BACKGROUND

The contribution of low-dose dopexamine to outcome, when given to increase cardiac output in patients already treated with fluids during major abdominal surgery, is not yet known.

METHOD

We carried out a randomized double-blind placebo-controlled trial. All 100 patients studied were given fluid infusions during surgery guided by stroke volume measurements made with an oesophageal Doppler probe. Patients were randomized to receive dopexamine at the rate of 0.25 microg kg(-1) min(-1) or saline 0.9% (control) for the first 24 h after the start of surgery. The primary outcome measure was the incidence of postoperative morbidity.

RESULTS

There were no statistically significant differences between groups in the incidence of postoperative complications, the length of hospital stay, the incidence of morbidity and the use of critical care facilities. The patients randomized to receive dopexamine had significantly more pre-existing disease than the control patients. Mortality in both groups was significantly less than predicted by the POSSUM (Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity) risk prediction score.

CONCLUSION

We could not demonstrate an advantage to using low-dose dopexamine in high-risk patients during major abdominal surgery.

Tonsillectomy by guillotine is less painful than by dissection

Most tonsillectomies are carried out by dissection. Only a small minority of otolaryngologists still routinely perform guillotine tonsillectomy. We carried out a prospective study on 86 children undergoing tonsillectomy utilising a standard anaesthetic and analgesic regimen to compare post-operative pain after dissection tonsillectomy and guillotine tonsillectomy using a Popper's hemostatic guillotine. Guillotine tonsillectomy was significantly less painful (P<0.001) than dissection tonsillectomy. The relative risk of experiencing moderately severe to severe pain was 0.36 (95% CI, 0.18-0.72) in the guillotine group. A significant proportion of children experience moderately severe to severe pain despite a comprehensive analgesic regimen confirming that post operative pain remains an important issue after this operation. On the basis of our findings we advocate tonsillectomy by guillotine in children. The less pain that arises within the first 24 h may be particularly important if performing tonsillectomy as a day-case procedure.

Regulation of human natural killer cell migration and proliferation by the exodus subfamily of CC chemokines

Natural killer (NK) cells play an important role in innate and adaptive immune responses to obligate intracellular pathogens. Nevertheless, the regulation of NK cell trafficking and migration to inflammatory sites is poorly understood. Exodus-1/MIP-3alpha/LARC, Exodus-2/6Ckine/SLC, and Exodus-3/MIP-3beta/ELC/CKbeta-11 are CC chemokines that share a unique aspartate-cysteine-cysteine-leucine motif near their amino terminus and preferentially stimulate the migration of T lymphocytes. The effects of Exodus chemokines on human NK cells were examined. Exodus-1, -2, and -3 did not induce detectable chemotaxis of resting peripheral blood NK cells. In contrast, Exodus-2 and -3 stimulated migration of polyclonal activated peripheral blood NK cells in a dose-dependent fashion. Exodus-2 and -3 also induced dose-dependent chemotaxis of NKL, an IL-2-dependent human NK cell line. Results of modified checkerboard assays indicate that migration of NKL cells in response to Exodus-2 and -3 represents true chemotaxis and not simply chemokinesis. Exodus-1, -2, and -3 did not induce NK cell proliferation in the absence of other stimuli. Nevertheless, Exodus-2 and -3 significantly augmented IL-2-induced proliferation of normal human CD56(dim) NK cells. In contrast, Exodus-1, -2, and -3 did not affect the cytolytic activity of resting or activated peripheral blood NK cells. Expression of message for CCR7, a shared receptor for Exodus-2 and -3, was detected in activated polyclonal NK cells and NKL cells but not resting NK cells. Taken together, these results indicate that Exodus-2 and -3 can participate in the recruitment and proliferation of activated NK cells. Exodus-2 and -3 may regulate interactions between T cells and NK cells that are crucial for the generation of optimal immune responses.

Private patients in NHS hospitals: comparison of two sources of information

BACKGROUND

The use of National Health Service (NHS) hospitals to treat private patients is debatable on the grounds of equity of access. Hospital Episodes Statistics (HES) annual reports are the only routine source of information on the scale of this activity. The accuracy of the information is doubted. This enquiry tested the completeness of HES data against information obtained directly from private patient unit managers.

METHOD

Managers of the 71 pay bed units in NHS hospitals in England were asked to supply from local registers and accounts the numbers of in-patients and day cases admitted in 1995-1996. Their reports were matched with the numbers of first consultant episodes for private in-patients and day cases shown for those hospitals in the HES data file for that year.

RESULTS

Of the 71 units 62 responded; 53 of these gave usable data. The 53 included, and 18 excluded from the comparison, matched on median and range of bed numbers. Managers identified 16 per cent more total admissions than did HES, 62,572 against 54,131; 13 per cent more in-patient admissions, 39,776 against 35,319; and 21 per cent more day cases, 22,796 against 18,812. More total admissions were reported by managers of 38 pay bed units than were recorded in HES, fewer by 12, and equal numbers by three. Similar sized discrepancies were noted for in-patient admissions and day cases. Reasons for the under-reporting of private patients in HES included the use of separate patient administration systems for private patients with a failure to feed data to HES, and the omission of some provider units altogether by a minority of trusts from the returns made to the Department of Health.

CONCLUSION

Overall, HES underestimates the amount of private patient activity reported directly by NHS hospitals. No method of validating private patient data is currently available. An amendment to an existing statistical return would provide a check on numbers. Central guidance on the inclusion of private patient activity in data transmitted by providers to the HES processing agency should be reinforced.

Ischemic preconditioning attenuates functional, metabolic, and morphologic injury from ischemic acute renal failure in the rat

Ischemic preconditioning has been shown to ameliorate injury due to subsequent ischemia in several organs. However, relatively little is known about preconditioning and the kidney. To address this, rats were randomized to control (C, N = 14), 2 min of ischemic preconditioning (P2 N = 10), 3 periods of 2 min of ischemia separated by 5 min periods of reflow (P2,3 N = 7), or three 5 min periods of ischemia separated by 5 min of reflow (P5,3 N = 6) prior to 45 min of bilateral renal ischemia followed by 24 hours of reperfusion. We observed a lower serum creatinine after 24 hours of reflow in P2, P2, 3 but not P5, 3 rats compared with C. Histology was examined in the C and P2, 3 groups and demonstrated less severe injury in the P2, 3 group. To gain insight into the mechanism by which preconditioning ameliorated ischemic injury, we performed near IR spectroscopy and 31P NMR spectroscopy. Based on near IR spectroscopy, the P2, 3 group had closer coupling of cytochrome aa3 redox state with that of hemoglobin during reflow. In the 31P NMR studies, the changes in ATP and pHi were similar during ischemia, but the P2, 3 group recovered ATP and pHi faster than C. These data suggest that ischemic preconditioning may ameliorate ischemic renal injury as assessed by functional, metabolic and morphological methods. The mechanism(s) by which this occurs requires additional study.

The MEDIGATE graphical user interface for entry of physical findings: design principles and implementation. Medical Examination Direct Iconic and Graphic Augmented Text Entry System

The solution to many of the problems of the computer-based recording of the medical record has been elusive, largely due to difficulties in the capture of those data elements that comprise the records of the Present Illness and of the Physical Findings. Reliable input of data has proven to be more complex than originally envisioned by early work in the field. This has led to more research and development into better data collection protocols and easy to use human-computer interfaces as support tools. The Medical Examination Direct Iconic and Graphic Augmented Text Entry System (MEDIGATE System) is a computer enhanced interactive graphic and textual record of the findings from physical examinations designed to provide ease of user input and to support organization and processing of the data characterizing these findings. The primary design objective of the MEDIGATE System is to develop and evaluate different interface designs for recording observations from the physical examination in an attempt to overcome some of the deficiencies in this major component of the individual record of health and illness.

Expectant management as an option for men with stage T1c prostate cancer: a preliminary study

The outcome of patients selecting observation of clinical stage T1c prostate cancer is unknown. A total of 101 men with clinical stage T1c prostate cancer were evaluated, counseled, and monitored in a standard fashion. Altogether, 27 men who elected observation were older and had greater co-morbidity but similar tumor characteristics as compared with 74 men who elected radical prostatectomy. In all, 9 men demonstrated clinical or biochemical evidence of progression after a mean follow-up of 23 months; 4 men who underwent radical prostatectomy had specimen-confined disease and undetectable post-operative levels of PSA. Observation appears to be a viable option for some men with clinical stage T1c prostate cancer.

Cutaneous pseudosarcomatous polyp: a histological and immunohistochemical study

Two unusual acquired polypoid skin lesions exhibited prominent histological atypia, but were biologically benign. Both patients were elderly females. The lesions clinically mimicked fibroepithelial polyp or nevus lipomatosus. Both had been present for about 20 years. One lesion was located on the back, the other on the posterior thigh. Each lesion exhibited dilated, hyalinized vessels in the dermis with focal fibrin deposits, myxoid stroma, and a population of bizarre, pleomorphic spindle to stellate cells, some of which were multinucleated. Occasional atypical mitoses were present. One lesion had abundant admixed fat. Immunohistochemical staining was strongly positive only for vimentin. The lesions share features with degenerating angiofibroma and vaginal pseudosarcomatous polyp. As in these lesions, the atypia is most probably reactive and degenerative.

Epidermolytic hyperkeratosis in nevi. A possible marker for atypia

Epidermolytic hyperkeratosis (EH) has been described as a reaction pattern in a variety of solitary skin lesions. We have noted that EH seems to occur more frequently in association with atypical than with typical acquired nevi. To support or refute this observation, the prevalence of EH in 250 cases of atypical compound nevi and in 250 cases of typical compound nevi was determined. EH was identified in 10 cases of atypical compound nevi and in two cases of typical compound nevi, which is a statistically significant difference with p value < 0.02. Since EH occurred in only 4% of atypical nevi examined, it should not be considered a diagnostic criterion. However, the identification of EH in otherwise histologically typical nevi should prompt the pathologist to make sure the lesion has been adequately sampled.

Comparison of subcapsular and total orchiectomy for treatment of metastatic prostate cancer

OBJECTIVES

To determine whether subcapsular orchiectomy provides suboptimal treatment of metastatic prostate cancer when used to avoid the psychologic consequences of the empty scrotum that results from total orchiectomy.

METHODS

We compared testosterone and prostate-specific antigen levels and survival of 37 patients who underwent total orchiectomy and 37 patients who underwent subcapsular orchiectomy for metastatic prostate cancer.

RESULTS

The two groups of 37 patients were similar by clinical parameters. Postoperatively, testosterone levels were 21 +/- 11 ng/dL for subcapsular versus 21 +/- 9 ng/dL for total orchiectomy patients. Tumor response was similar in the two groups when assessed by prostate-specific antigen measured 3 weeks, 6 months, and 1, 2, and 3 years postoperatively. Survival was similar when assessed using Kaplan-Meier analysis (P = 0.76).

CONCLUSIONS

Subcapsular orchiectomy is a viable option for treatment of metastatic prostate cancer.

The epidemiology of sports and exercise related injury in the United Kingdom

A national study of exercise related morbidity (ERM) in England and Wales was carried out using a postal questionnaire sent to 28,857 adults aged 16-45 years. The questionnaire asked about regular participation in sports or other recreational fitness activities involving physical exercise, and for details of any injuries occurring during a 28 d reference period. A return rate of 68% was achieved. Comparisons with other national data sources indicated that the information obtained was reliable. It is estimated that each year there are 29 million incidents resulting in new or recurrent injuries, however minor, of which 9.8 million (95% confidence interval 8.1 to 11.4 million) result in new 'substantive' injuries which are potentially serious, result in treatment, or in participants being unable to take part in their usual activities. Soccer accounted for more than 25% of all ERM, but the risk of a substantive injury in rugby was three times that in soccer. Over one third of ERM occurred in men aged 16-25 years. The most frequently reported injuries were sprains and strains of the lower limbs. Treatment was sought in approximately 25% of ERM incidents and 7% of all new ERM incidents involved attendance at a hospital accident and emergency department. The treatment provider most likely to be consulted was a general practitioner, but physiotherapists and complementary medicine practitioners were also consulted frequently. To maximize the health benefits of exercise, research strategies to reduce the volume and severity of ERM and to identify the most appropriate ways of managing ERM should be set.

Intracorneal nuclear dust aggregates in dermatitis herpetiformis. A clue to diagnosis

Dermatitis herpetiformis has a characteristic histologic pattern consisting of subepidermal blisters often containing fibrin, infiltrates of neutrophils and nuclear dust at tips of dermal papillae, and papillary dermal edema. These are features of early and evolving lesions. We present two cases of clinically typical dermatitis herpetiformis with previously unreported histologic features that may provide a significant diagnostic clue. In each of these cases there were focal collections of nuclear dust in the cornified layer of the epidermis, a finding that may represent a resolving phase of dermatitis herpetiformis, beyond the usual papillary dermal neutrophilic microabscesses seen in early lesions. Biopsy material was available for immunofluorescent studies in one of the cases presented. In addition to the granular pattern of IgA positivity at the dermal-epidermal junction, which is diagnostic of dermatitis herpetiformis, this biopsy also showed similar IgA positivity in the intracorneal nuclear dust aggregates. In the second case, initial sections showed only intracorneal nuclear dust, but at deeper levels there were more typical diagnostic microabscesses at the tips of dermal papillae.

The left ventricular resectoscope. A new instrument for the comprehensive resection of the left ventricular outflow tract in hypertrophic obstructive cardiomyopathy (HCOM)

After disappointing results with non-surgical measures there is now a move back towards surgical left ventricular outflow tract resection as a treatment of choice for hypertrophic obstructive cardiomyopathy. The traditional operation presents various technical difficulties and occasionally disappointing results. Using a diathermy loop to resect the hypertrophied outflow tract has provided a much more convenient and reliable technique. This paper describes an instrument incorporating all the features of this technique (Left ventricular resectoscope).

Therapeutic implications of lymph nodal spread in lateral T1 and T2 squamous cell carcinoma of the vulva

From 1963 to 1993, 157 patients with primary squamous cell carcinoma of the vulva were treated by radical surgery at the University of Kentucky Medical Center. There were 84 unilateral lesions confined to the labium majus or labium minus. Thirty-seven patients had T1 lesions, median diameter 1.5 cm (range 0.5-2.0 cm), and 47 patients had T2 lesions, median diameter 3.4 cm (range 2.2-9.0 cm). Radical vulvectomy with bilateral inguinal lymphadenectomy was performed in 56 patients and radical hemivulvectomy with selective inguinal lymphadenectomy in 28 patients. An average of 8 nodes was removed with superficial inguinal lymphadenectomy and 13 nodes with superficial and deep inguinal lymphadenectomy. Deep inguinal lymph node metastases occurred only in patients with positive superficial inguinal lymph nodes. There were no contralateral inguinal lymph node metastases in any lateral T1 or T2 lesion. Following surgery, patients were followed 1-15 years (mean 5.0 years) and none have been lost to follow-up. Nine patients developed ipsilateral recurrences, but no contralateral recurrences were noted. Seven of these patients developed local recurrences to the ipsilateral vulvar skin and were cured by reexcision. Two patients (2.4%), both of whom had positive ipsilateral superficial and deep inguinal lymph node metastases at the time of initial surgery, developed distant metastases and died of disease 10 and 11 months after treatment. These data suggest that deep inguinal lymph nodal metastases occurred only in patients with superficial inguinal node involvement. Contralateral inguinal lymph nodal metastases are extremely rare in lateral T1 and T2 vulvar squamous cell carcinomas. Radical hemivulvectomy is as effective as radical vulvectomy in the treatment of lateral T1 and T2 vulvar squamous cell cancers.

Cost effectiveness of adjuvant bile salt treatment in extracorporeal shock wave lithotripsy for the treatment of gall bladder stones

The relative cost effectiveness of adjuvant urso and chenodeoxycholic acid treatment in extracorporeal shockwave lithotripsy (ESWL) has been assessed as part of a pragmatic randomised controlled trial of ESWL as a treatment of gall bladder stones. Of the first patients with gall stone volume < 4 cm3 randomised to ESWL in the main trial, 24 were randomised to have ESWL alone and 26 to have adjuvant bile acid treatment, one of whom died before the end of the 12 month follow up period. At 12 months after treatment, differences in gall stone clearance between ESWL alone (3/24 (13%) clear, 5 (21%) referred for surgery) and ESWL and bile acids (6/25 (24%) clear, 2 (8%) referred for surgery) were not significant (p = 0.36, log rank test). Patients in both groups had substantial and significant health gains (according to biliary pain frequency and severity, Nottingham Health Profile scores, visual analogue scale symptom scores, and complications) but there were no significant differences between the groups. Improvements in both groups usually occurred within a few weeks of treatment and were unrelated to gall stone clearance. Costs were greater in the bile salt group (95% confidence intervals for estimated cost difference: 90 pounds to 630 pounds). If the purpose of treatment is symptom relief rather than gall stone clearance then adjuvant bile salt treatment seems to be unnecessary.

Quality of minor surgery by general practitioners in 1990 and 1991

BACKGROUND

The 1990 contract for general practitioners encouraged them to undertake minor surgical procedures in their practices.

AIM

A study was undertaken to determine whether the subsequent expansion of general practitioner minor surgery activity was accompanied by changes in quality of care.

METHOD

Data were analysed relating to minor operations conducted in 22 practices during April-June 1990 and April-June 1991.

RESULTS

The volume of general practitioner minor surgery increased by 41% between the two study periods. Waiting time, accuracy of diagnosis, use of histology, adequacy of excision, complications and the need for corrective treatment in hospital did not change significantly between the two periods.

CONCLUSION

The findings do not support suggestions that the expansion of general practitioner minor surgery activity following the 1990 contract has been associated with an erosion of quality of care.

Patient characteristics and clinical caseload of short stay independent hospitals in England and Wales, 1992-3

OBJECTIVE

To describe and quantify the patients and clinical activities of independent short stay hospitals.

DESIGN

Retrospective survey of hospital records for sampled periods of one financial year and comparison with data from 1981 to 1986.

SETTING

217 independent hospitals in England and Wales, 1992-3.

MAIN OUTCOME MEASURES

Distributions of sex, age groups, and areas of residence of patients, clinical procedures, financial provision.

RESULTS

Data were obtained from 201 (93%) hospitals. An estimated 429,172 inpatients (7% more than 1986) and 249,531 day cases (an increase of 154%) from 1986 were treated in the year. The number of overseas patients was half that in 1986. Clinical case mix remained similar to 1986. Abortion remained the commonest procedure (13% v 19% in 1986). Lens operations, heart operations, endoscopies, and non-surgical cases showed the largest increases from 1986. Proportionately more overseas patients had abortions (30% v 12% for England and Wales residents) and they received 41% of coronary artery bypass grafting. Three quarters of the patients were aged 15-64. The proportion of patients aged over 65 had changed little (19% v 17% in 1986). Estimated average bed occupancy was only 48%. Only one in 20 patients was treated under NHS contract; 90% of episodes were funded through private health insurance.

CONCLUSIONS

The demand for treatment in private hospitals continues to increase despite additional investment in the NHS, but the overseas market is falling. Overall, the range of clinical activity has changed little.

The Alcohol Problems Questionnaire: reliability and validity

The Alcohol Problems Questionnaire (APQ) was designed as a clinical instrument for measuring alcohol-related problems. It has been used to study the relationship between alcohol-related problems and dependence within the bi-axial model. The reliability of the APQ was, however, unknown. In the present study 101 subjects participated in a test-retest reliability study. Dependence and consumption scores were obtained along with socio-demographic information in order to study the construct validity of the APQ. The APQ was found to be highly reliable and the previous finding that dependence is a mediating factor in the relationship between consumption and problems was replicated. These findings add further weight to the view that alcohol-related problems represent a phenomenon which is conceptually, as well as statistically, distinct from dependence. Further, the APQ is reliable, simple to administer and is likely to be useful in the assessment and study of problem drinkers in the clinical and research settings.

Coumarin (1,2-benzopyrone) for the treatment of prostatic carcinoma

The unavailability of effective treatment for metastatic hormone-refractory and clinically localized but pathologically unfavorable prostatic carcinoma warrants trial of new and promising treatments. Preliminary studies in patients with metastatic disease have shown (a) subjective but no objective responses to 100 mg coumarin and cimetidine daily; (b) objective responses in 3 of 40 patients treated with 3 g coumarin daily, all of whom had normal performance status and 1 of whom remains with three resolved bone metastases and stable prostate-specific antigen levels after 4 years; (c) toxicity only in bedridden patients. We recently initiated two multi-center trials of 1 g coumarin daily. Metastatic prostatic carcinoma patients of normal performance status were treated in a phase II trial. Patients who had been treated by radical prostatectomy, but had surgical margin, seminal vesicle or lymph node involvement or detectable prostate-specific antigen after radical prostatectomy, were randomized to coumarin or placebo.

Minor surgery by general practitioners under the 1990 contract: effects on hospital workload

OBJECTIVE

To determine the extent to which minor surgery undertaken by general practitioners after the introduction of the 1990 contract substituted for hospital outpatient workload.

DESIGN

Before and after observational study.

SETTING

Four English family health services authorities.

SUBJECTS

Patients in 22 practice populations who were operated on by their general practitioner or referred to hospital for minor surgery during April to June 1990 or April to June 1991.

MAIN OUTCOME MEASURES

Numbers of minor surgical procedures undertaken in general practice and in hospital, numbers of referrals to hospitals for conditions treatable by a minor surgical procedure, and the mix of diagnoses and procedures undertaken in each setting.

RESULTS

General practitioners claimed reimbursement for 600 minor surgical procedures during April to June 1990 and for 847 during April to June 1991, an increase of 41%. Referrals to hospital for comparable conditions showed no compensatory decrease (385 during April to June 1990 and 388 during April to June 1991, 95% confidence interval for change in referrals -51 to 57), and the number of hospital procedures resulting from those referrals also remained constant (187 in the first period, 189 in the second, 95% confidence interval for change in procedures -36 to 40). The mix of procedures did not change significantly from one study period to the next in either setting.

CONCLUSIONS

Many or all of the additional patients receiving minor surgery under the terms of the 1990 contract may not have previously been referred to hospital. General practitioners seem not to have systematically shifted towards treating the more trivial cases. The overall increase in minor surgical activity may reflect an improvement in accessibility of care or changes in patients' perceptions and attitudes.

Case against targeting long term non-attenders in general practice for a health check

A study was undertaken to describe the consequences of implementing that part of the 1990 contract for general practitioners which requires them to offer health checks to all patients aged 16-74 years not seen within the previous three years. A random sample of 679 patients who had not attended for three years and 379 patients who had attended in this period were identified from 30 practice lists (including eight inner city practices) in five family health services authority areas. All patients were sent an invitation to a health check by their own practice and an attempt was made by the research team to conduct a home interview. The results showed that a considerable proportion of non-attenders were not in a position to take advantage of such an invitation; 17% of those at inner city practices were known to have received the invitation, 68% in practices elsewhere. Interviewed non-attenders (76% of those known to have received their invitation) had sociodemographic characteristics similar to the comparison group of interviewed attenders, although women aged 55-74 years were over-represented. At interview, non-attenders reported relatively less use of accident and emergency services and preventive health care and scored significantly better on all six dimensions of the perceived health status measure. Overall, 3% of all identified non-attenders in the inner city practices and 13% elsewhere accepted the invitation to a health check. Low levels of morbidity were found at health checks for those who had and who had not attended their general practitioners in the previous three years.(ABSTRACT TRUNCATED AT 250 WORDS)

Probability graphics support for medical reasoning

Graphic displays of data from clinical observations and laboratory testing provide important support to the health practitioner in managing an increasing amount of complex information. A graphic display program is described that preserves much of the context of data that is important to their evaluation, and that maintains a sense of the strength of the signal when aberrant data are encountered.