Population-weighted degree-days: The global shift between heating and cooling

Anthropogenic greenhouse gas emissions are driving global increases in temperature. This rise will likely lead to an increase in demand for cooling in the coming years. However, increasing temperatures are not the main explanatory factor for why the world is moving towards more cooling. This paper compares population and area-weighted cooling and heating degree-days derived using ERA5-Land reanalysis temperature, to show that population growth in warmer parts of the world drives cooling demand globally. The analysis shows that mean global area-weighted heating degree-days have fallen 8.46 °C days/year, whereas population-weighted heating degree-days have fallen by 12.5 °C days/year. At the same time, mean global area-weighted cooling degree-days have risen by 3.0 °C days/year, while population-weighted cooling degree-days have risen at 6.0 °C days/year. By using sub-country analysis, this paper shows that population-weighted degree-days can substantially differ from area-weighted degree-days. Finally, the findings highlight that the choice of heating and cooling degree-day base temperature is the most important parameter in the variability of degree-days and will need to be understood better in order to accurately account for future heating and cooling energy demand.

30 Informant-Reported Decline Associates with Silent Acute Stroke Lesions and Worse Small Vessel Disease in Mild Stroke Patients

Introduction

Small vessel disease (SVD) commonly causes stroke and dementia. Early clinical predictors of disease progression are lacking. We aimed to determine whether informant reports of chronic cognitive/functional decline, prerequisites for dementia diagnosis, are associated with (a)baseline SVD burden, measured by Fazekas scores and (b)SVD change, measured by incident subcortical Diffusion-weighted Imaging (DWI) lesions.

Method

We prospectively recruited patients with mild ischaemic stroke, performed diagnostic MRI, and invited participants to repeat MRI 3- to 6-monthly. Informants completed the Informant Questionnaire for Cognitive Decline in the Elderly (IQCODE) prior to baseline visit, a 16-item questionnaire which assesses patients’ cognitive and functional decline in the preceding ten years. Scores range from 1–5: a score above 3.3 has high sensitivity/specificity for dementia post-stroke. We conducted linear regression with IQCODE as the dependent variable, adjusting for age, sex, baseline MoCA, disability (modified Rankin Scale).

Results

We recruited 106 participants (mean age 67 years;range 40–86;33% female). Ninety-three informant questionnaires were returned. IQCODE associated with baseline Fazekas score; Fazekas 6 (β = 0.28, p = 0.04) vs. Fazekas 3 (β = 0.03, p = 0.67), R2 = 0.11, adjusted for age, sex, baseline MoCA, disability.

Incident DWI lesions were common (15/106; 14/15 subcortical; no active embolic sources; median 67 days post-stroke). Four were asymptomatic, two reported stroke-like symptoms and nine had neuropsychiatric/non-focal symptoms. IQCODE was higher in those with a new lesion vs. without (β = 0.21, p = 0.02), R2 = 0.09, while age (β = −0.004, p = 0.19), MoCA (β = −0.006, p = 0.56) and disability (β = 0.06, p = 0.2) were not.

Conclusions

Higher SVD burden and incident, mostly “silent” stroke lesions associate more strongly with informant concerns of cognitive/functional decline than age or objective cognitive tests. These findings are novel in an ischaemic stroke population and the first to assess IQCODE/SVD progression. Future work should determine whether combining informant reports with imaging features of small vessel disease improves early detection of dementia.

Finding Ethical Principles and Practical Guidelines for the Controlled Flow of Patient Data

The application of computing to health care, and particularly to electronic patient records, offers major benefits but raises issues of confidentiality and of potential misuse. Sound access control mechanisms are therefore important, but most models focus upon informed consent by the data subject. This raises challenges in mental health care, and for other vulnerable patients including those comatose, and the severely ill and temporarily distressed. Published algorithms which are used to control record access within a controlled environment therefore have value, as a means of ensuring an open and informed, yet ethically sound, solution. The paper describes the background and issues, and gives an example of such an algorithm.

The impact of assertive outreach teams on hospital admissions for psychosis: a time series analysis

Although the assertive outreach model was developed in the United States and imported to the United Kingdom to date, there is only limited evidence to support its wide-scale implementation within the United Kingdom. This is the first study to have combined a large dataset with this type of research method to explore the impact of assertive outreach teams on hospital admissions. The introduction and expansion of assertive outreach teams was associated with reducing hospital admissions for people with psychosis. This study found a consistent summer peak in hospital admissions which community and in-patient mental health nurses should take account of and plan for. Ever since the Mental Health Policy Implementation Policy Guide paved the way for the introduction of the Assertive Outreach Treatment (AOT) model in England, the impact of this approach has been the subject of considerable debate but limited evaluation. To date, most of the evidence supporting this model has originated from outside the United Kingdom. A central aim of the AOT was to reduce the need for in-patient treatment. We aimed to assess the impact of the AOT model on hospital admissions for people with psychosis in England. Interrupted time series analysis was used in this study to evaluate the impact of the policy change. Following the introduction of the AOT model, a statistically significant reduction in hospital admissions for psychosis was found. In addition, we observed a repeated, annual summer peak in admissions. This study adds to the international evidence which supports the effectiveness of the AOT model in reducing hospital admissions for people with severe mental health problems. We offer five suggested implications for mental health nurses and clients based on our findings.

The modifying effect of the building envelope on population exposure to PM2.5 from outdoor sources

A number of studies have estimated population exposure to PM2.5 by examining modeled or measured outdoor PM2.5 levels. However, few have taken into account the mediating effects of building characteristics on the ingress of PM2.5 from outdoor sources and its impact on population exposure in the indoor domestic environment. This study describes how building simulation can be used to determine the indoor concentration of outdoor-sourced pollution for different housing typologies and how the results can be mapped using building stock models and Geographical Information Systems software to demonstrate the modifying effect of dwellings on occupant exposure to PM2.5 across London. Building archetypes broadly representative of those in the Greater London Authority were simulated for pollution infiltration using EnergyPlus. In addition, the influence of occupant behavior on indoor levels of PM2.5 from outdoor sources was examined using a temperature-dependent window-opening scenario. Results demonstrate a range of I/O ratios of PM2.5 , with detached and semi-detached dwellings most vulnerable to high levels of infiltration. When the results are mapped, central London shows lower I/O ratios of PM2.5 compared with outer London, an apparent inversion of exposure most likely caused by the prevalence of flats rather than detached or semi-detached properties.

PRACTICAL IMPLICATIONS

Population exposure to air pollution is typically evaluated using the outdoor concentration of pollutants and does not account for the fact that people in London spend over 80% of their time indoors. In this article, building simulation is used to model the infiltration of outdoor PM2.5 into the domestic indoor environment for dwellings in a London building stock model, and the results mapped. The results show the variation in relative vulnerability of dwellings to pollution infiltration, as well as an estimated absolute indoor concentration across the Greater London Authority (GLA) scaled by local outdoor levels. The practical application of this work is a better understanding of the modifying effect of the building geometry and envelope design on pollution exposure, and how the London building stock may alter exposure. The results will be used to inform population exposure to PM2.5 in future environmental epidemiological studies.

The modifying effect of the building envelope on population exposure to PM2.5 from outdoor sources

A number of studies have estimated population exposure to PM2.5 by examining modeled or measured outdoor PM2.5 levels. However, few have taken into account the mediating effects of building characteristics on the ingress of PM2.5 from outdoor sources and its impact on population exposure in the indoor domestic environment. This study describes how building simulation can be used to determine the indoor concentration of outdoor-sourced pollution for different housing typologies and how the results can be mapped using building stock models and Geographical Information Systems software to demonstrate the modifying effect of dwellings on occupant exposure to PM2.5 across London. Building archetypes broadly representative of those in the Greater London Authority were simulated for pollution infiltration using EnergyPlus. In addition, the influence of occupant behavior on indoor levels of PM2.5 from outdoor sources was examined using a temperature-dependent window-opening scenario. Results demonstrate a range of I/O ratios of PM2.5 , with detached and semi-detached dwellings most vulnerable to high levels of infiltration. When the results are mapped, central London shows lower I/O ratios of PM2.5 compared with outer London, an apparent inversion of exposure most likely caused by the prevalence of flats rather than detached or semi-detached properties.

PRACTICAL IMPLICATIONS

Population exposure to air pollution is typically evaluated using the outdoor concentration of pollutants and does not account for the fact that people in London spend over 80% of their time indoors. In this article, building simulation is used to model the infiltration of outdoor PM2.5 into the domestic indoor environment for dwellings in a London building stock model, and the results mapped. The results show the variation in relative vulnerability of dwellings to pollution infiltration, as well as an estimated absolute indoor concentration across the Greater London Authority (GLA) scaled by local outdoor levels. The practical application of this work is a better understanding of the modifying effect of the building geometry and envelope design on pollution exposure, and how the London building stock may alter exposure. The results will be used to inform population exposure to PM2.5 in future environmental epidemiological studies.

Interethnic marriage: identifying the second generation in Australia

"Studies in Australia show that an increasing proportion of the population have ancestors from more than one country. Evidence regarding differences in the marriage patterns of first and second generation migrants has been restricted in scope as published marriage registration data includes only birthplace of partners. Marriage registration records include information about the birthplace of parents of partners, but is available only through specially produced tabulations. Changes in the census for 1986 and 1991 make it possible to identify the second generation in households, and this article examines the use of census data as an alternative to marriage registration records in tracing changes in intermarriage patterns and differences between urban and rural areas."

CD40 and CD86 upregulation with divergent CMRF44 expression on blood dendritic cells in inflammatory bowel diseases

OBJECTIVE

Dendritic cells (DC) are the only antigen-presenting cells that can activate naïve T lymphocytes and initiate a primary immune response. They are also thought to have a role in immune tolerance. DC traffic from the blood to peripheral tissue where they become activated. They then present antigen and the costimulating signals necessary to initiate an immune response. In this study, we investigated the number, subsets, and activation pattern of circulating and intestinal DC from patients with clinically mild ulcerative colitis (UC) or Crohn's disease.

METHODS

Patients were recruited, if they were not taking immunosuppressive therapy, and were assessed for clinical severity of their disease using for UC, the Clinical Activity Index, and for Crohn's disease, the Crohn's Disease Activity Index. Blood CD11c+ and CD11c- DC subsets, expression of costimulatory antigens, CD86 and CD40, and the early differentiation/activation antigen, CMRF44, were enumerated by multicolor flow cytometry of lineage negative (lin- = CD3-, CD19-, CD14-, CD16-) HLA-DR+ DC. These data were compared with age-matched healthy and the disease control groups of chronic noninflammatory GI diseases (cGI), acute noninflammatory GI diseases (aGI), and chronic non-GI inflammation (non-GI). In addition, cryostat sections of colonoscopic biopsies from healthy control patients and inflamed versus noninflamed gut mucosa of inflammatory bowel disease (IBD) patients were examined for CD86+ and CD40+ lin- cells.

RESULTS

Twenty-one Crohn's disease and 25 UC patients, with mean Crohn's Disease Activity Index of 98 and Clinical Activity Index of 3.1, and 56 healthy controls, five cGI, five aGI, and six non-GI were studied. CD11c+ and CD11c- DC subsets did not differ significantly between Crohn's, UC, and healthy control groups. Expression of CD86 and CD40 on freshly isolated blood DC from Crohn's patients appeared higher (16.6%, 31%) and was significantly higher in UC (26.6%, 46.3%) versus healthy controls (5.5%, 25%) (p = 0.004, p = 0.012) and non-GI controls (10.2%, 22.8%) (p = 0.012, p = 0.008), but not versus cGI or aGI controls. CD86+ and CD40+ DC were also present in inflamed colonic and ileal mucosa from UC and Crohn's patients but not in noninflamed IBD mucosa or normal mucosa. Expression of the CMRF44 antigen was low on freshly isolated DC, but it was upregulated after 24-h culture on DC from all groups, although significantly less so on DC from UC versus Crohn's or healthy controls (p = 0.024). The CMRF44+ antigen was mainly associated with CD11c+ DC, and in UC was inversely related to the Clinical Activity Index (r = -0.69, p = 0.0002).

CONCLUSIONS

There is upregulation of costimulatory molecules on blood DC even in very mild IBD but surprisingly, there is divergent expression of the differentiation/activation CMRF44 antigen. Upregulation of costimulatory molecules and divergent expression of CMRF44 in blood DC was also apparent in cGI and aGI but not in non-GI or healthy controls, whereas intestinal CD86+ and CD40+ DC were found only in inflamed mucosa from IBD patients. Persistent or distorted activation of blood DC or divergent regulation of costimulatory and activation antigens may have important implications for gut mucosal immunity and inflammation.

Finding ethical principles and practical guidelines for the controlled flow of patient data

The application of computing to health care, and particularly to electronic patient records, offers major benefits but raises issues of confidentiality and of potential misuse. Sound access control mechanisms are therefore important, but most models focus upon informed consent by the data subject. This raises challenges in mental health care, and for other vulnerable patients including those comatose, and the severely ill and temporarily distressed. Published algorithms which are used to control record access within a controlled environment therefore have value, as a means of ensuring an open and informed, yet ethically sound, solution. The paper describes the background and issues, and gives an example of such an algorithm.

Towards an ethical protocol in mental health informatics

Application of informatics to mental health has the potential to benefit a disadvantaged yet important patient group. At the same time, difficult issues are raised with regard to data protection and ethics because many patients are not able to express informed and rational views, and this increases their vulnerability. However, developments in this field are limited, and there is little literature. Generic data protection legislation and guidance assumes that data subjects are mentally competent adults. This paper distils key ethical issues and principles in mental health informatics, and describes a process which has initiated the identification of "reasonable" practice.

Does resuscitation produce a reperfusion injury?

Conceptually, shock with resuscitation should produce cellular changes that parallel those observed in a single organ exposed to ischemia with reperfusion, i.e., a transient worsening of the injury pattern after reperfusion with the degree of recovery reflecting the magnitude of the ischemic injury. To test this hypothesis, 74 male Sprague Dawley rats (300-400 g) were randomized into two groups with controls and exposed to 1) hemorrhagic shock (mean arterial pressure < 50 mm Hg) for 2 hours before sacrifice, or 2) shock (2 hours) with reinfusion of shed blood over 1 hour before sacrifice. Mean arterial pressure, blood loss, serum lactate, base excess, and bicarbonate were serially measured to determine the degree of tissue ischemia. At sacrifice, hepatic mitochondrial function was determined by the respiratory control ratio. Our findings were as follows: 1) Hemorrhagic shock produced significant (P < 0.001) tissue ischemia and impairment of mitochondrial function (P < 0.001), 2) resuscitation rapidly corrects the metabolic sequelae of tissue ischemia, and 3) mitochondrial function was unaffected by resuscitation. We conclude that resuscitation rapidly corrects the tissue ischemia associated with hemorrhagic shock, without producing any measurable reperfusion injury at the mitochondrial level.

Hepatic and cerebrospinal fluid accumulation of aluminium and bismuth in volunteers taking short course anti-ulcer therapy

To investigate the possible absorption and deposition of bismuth or aluminium from agents used in the treatment of peptic ulcers, we have measured levels of bismuth and aluminium in the liver tissue of 15 patients undergoing elective liver biopsy and in the cerebrospinal fluid (CSF) of 15 patients undergoing elective myelography after administration of standard therapeutic doses of tripotassium dicitrato bismuthate (TBS), sucralfate or aluminium hydroxide for 1 month. Aliquots of liver or CSF were separated and levels of both aluminium and bismuth were assayed in each sample by atomic absorption spectrophotometry. The group who received TBS had significantly higher liver bismuth levels than the other two treatment groups, but there was no significant difference in CSF bismuth levels among the three groups. There was no significant difference in either liver or CSF aluminium levels among the three treatment groups. We conclude that tissue accumulation of bismuth may occur after short-course therapy with colloidal bismuth, although there is no evidence of CNS accumulation of bismuth in the present study.

The care programme approach at work in mental health care

The care programme approach provides a system whereby the client is placed at the centre of everything professionals do. A client's action plan is drawn up, with the role of each professional made explicit, including the time of his or her involvement. Finally, a date is set to review the package of care. This paper aims to show how such a system has been applied and provides an example through a care study.

Management of a persistent pancreatic fistula secondary to a ruptured pseudocyst with endoscopic insertion of an expandable metal stent

A case of pancreatic fistula successfully managed by the endoscopic insertion of an expanding-mesh metal stent into the pancreatic duct is reported. The patient had developed a fistula following rupture of a pancreatic pseudocyst, and attempted transpapillary drainage using plastic endoprostheses had failed due to prosthesis migration. Insertion of a Strecker metal stent was followed by rapid and sustained clinical improvement and cessation of fistula drainage.

Severe superior vena caval syndrome after the Mustard repair in a patient with persistent left superior vena cava

This report describes our experience with a 6-year-old girl with dextro-transposition of the great arteries and persistent left superior vena cava, who manifested severe superior vena caval syndrome following a Mustard repair. A direct end-to-end anastomosis of the left superior vena cava to the left atrial appendage, which formed part of the systemic venous atrium, was performed with excellent relief of the obstruction. The rationale for application of this method is discussed as an alternative to the use of cardiopulmonary bypass for intra-atrial baffle revision.

A role for endothelin and nitric oxide in the pressor response to diaspirin cross-linked hemoglobin

Diaspirin-cross-linked hemoglobin (DCLHb; Baxter Healthcare Corp) has potential for clinical use as a hemoglobin-based oxygen-carrying solution. We have previously shown that DCLHb administration is associated with a self-limiting increase in mean arterial pressure (MAP). Based on in vitro studies with other hemoglobin solutions, this vasopressor effect is thought to be mediated at least in part by the release or inhibition (or both) of endothelium-derived vasoactive substances. The purpose of our studies was to determine the role of endothelin (ET), a potent vasoconstrictor peptide, and nitric oxide, a vasodilator, in mediating the pressor effect of DCLHb in conscious rats. Intravenous administration of DCLHb has been shown to elicit an immediate increase in MAP that peaks within 30 minutes and returns to baseline by 300 minutes in a dose-dependent fashion. Phosphoramidon, an inhibitor of proendothelin conversion to ET, attenuated the elevation of MAP when administered before DCLHb. Administration of cyanomet DCLHb, a DCLHb molecule that is unable to interact with NO, was not associated with an elevation of MAP. L-arginine, the substrate for NO synthesis, and nitroglycerin, an NO donor, significantly reduced MAP when infused 15 minutes after DCLHb administration. Based on these findings, we conclude that the DCLHb-induced elevation of MAP in vivo is mediated at least in part by ET and the inhibition of NO. Although these data support earlier reports of hemoglobin binding NO, this is the first report of the pressor response to hemoglobin being attenuated by an agent that blocks the conversion of proendothelin to ET.

Palliation of biliary obstruction in patients with advanced breast cancer using endoscopic stents

Endoscopic insertion of a biliary endoprosthesis was successful in eight patients with extrahepatic biliary obstruction caused by breast cancer metastases. The serum bilirubin level was significantly reduced in seven patients and in four this was accompanied by marked symptomatic improvement. Endoprostheses required replacement after a median of 8 (range 3-127) weeks. Two patients responding to systemic anticancer therapy survived 27 and 43 months. Endoscopically placed stents offer effective palliation of extrahepatic biliary obstruction caused by metastatic breast cancer and long-term survival may be possible.

Endoscopic management of bile duct stones at Auckland Hospital in 1988 and 1989

OBJECTS

to define the role of endoscopic management of bile duct calculi in a tertiary referral institution.

METHODS

an unselected series of 466 patients presenting for ERCP over a two year period were reviewed and 103 patients with bile duct calculi identified. The results of endoscopic management of these patients is reviewed.

RESULTS

endoscopic sphincterotomy was successful in 98% of patients, and resulted in clearance of calculi from the bile duct in 75%, and in a further 8% symptoms were successfully controlled by sphincterotomy with or without endoprostheses, despite residual calculi. Seventy-nine percent of the patients with choledocholithiasis were successfully managed endoscopically, minor complications occurring in 16% which were significant in only 4%, with no procedure related mortality.

CONCLUSIONS

endoscopic sphincterotomy provides a safe and effective means of managing bile duct calculi, even if stone extraction cannot be completed.

Duodenal ulcer relapse after eradication of Helicobacter pylori

Thirty-six patients with healed duodenal ulcers, 27 infected with Helicobacter pylori and nine uninfected, were followed for up to 12 months to determine the rate of ulcer relapse. Eight patients withdrew over the follow up period. At one year, 15 of 20 (75%) infected patients and one of eight (13%) uninfected patients had relapsed, p less than 0.05. Eradication of H pylori favourably influences the natural history of duodenal ulcer recurrence. Significant patient morbidity may be prevented by using measures to eradicate H pylori during or after duodenal ulcer healing.

Use of an alternative guidewire system in endoscopic placement of biliary endoprosthesis

A new guidewire with increased flexibility, torque control and a new smooth outer coating has been designed for use in interventional vascular radiology. The successful use of an adaptation of it in endoscopic management of malignant biliary strictures is reported.

Intestinal pseudoobstruction secondary to amyloidosis responsive to cisapride

A case of chronic intestinal pseudoobstruction secondary to systemic amyloidosis in a patient with multiple myeloma is described. Gastrointestinal symptoms and indices of nutrition improved markedly after commencing treatment with cisapride, which may have been responsible for relatively prolonged survival compared with similar reported cases.

Introduction of an appointment system in a general practice: surveys of patients and staff

To aid discussion on the introduction of an appointment system in an inner city practice with a 'walk-in' (non-appointment) system, we surveyed, firstly, patients' and staff members' attitudes to appointment systems, and secondly, aspects of the functioning of the current system. Of 250 patients in the first survey 73 per cent were against appointment systems while 24 per cent indicated that they would consider registering with another practice if such a system were introduced. Adverse comments about appointment systems greatly outweighed favourable ones. Staff members perceived clear advantages and disadvantages of both methods of consulting e.g. the 'walk-in' system was thought to be stressful due to the unpredictable workload but thought to reduce the demand for housecalls. Appointment systems were seen as giving staff more control over consulting but as less flexible for the patient. In the second survey of 352 patients, 17 per cent estimated a wait of 10 minutes or less for their consultation, 62 per cent estimated it as 10 to 20 minutes and 21 per cent as more than 30 minutes. Further, 68 per cent of patients estimated that their consultation lasted five minutes or less and 27 per cent indicated that the doctor seemed rushed. As a compromise between the wishes of patients and the needs of staff, 'walk-in' morning surgeries and appointment-only evening surgeries are now offered.

Evaluation of a practice information leaflet

Over 10 months 5,000 practice information leaflets were distributed in a practice in Glasgow. The leaflet was principally evaluated by assessing patients' attitudes to and use of leaflets and changes in their knowledge about the practice. Changes in the pattern of consultation with the practice nurse and the timing of incoming telephone calls were also measured. Most patients read, kept and referred to the leaflet and reported it to be useful. Those who had seen the leaflet had significantly greater knowledge (mean knowledge score 7.5) on 15 questions on practice organization than two comparison groups: the base-line study sample (mean knowledge score 5.2) and those in the follow-up sample who had not seen the leaflet (mean knowledge score 5.7). Improvements in knowledge were statistically significant for 10 out of 15 questions. Two changes of behaviour were noted, increased self-referral to nurses (37% of new consultations at follow-up were self-referred compared with 29% at baseline: P = 0.05) and the timing of incoming telephone calls was more in line with practice policy (for example, 23% of calls for repeat prescriptions were made between 12.00 and 16.00 hours at follow-up compared with only 11% at baseline, P less than 0.001). The leaflet was judged to be useful.

Effects of human and ovine pancreatic secretory trypsin inhibitors on the proliferation of normal human fibroblasts

Human pancreatic secretory trypsin inhibitor inhibited cell-surface proteolytic activity in human fibroblasts. In the range of concentrations which caused proteinase inhibition, fibroblast proliferation was also inhibited by this reagent and by the ovine equivalent. At lower concentrations, there was some evidence for a mitogenic effect, and this was confirmed by obvious stimulation of DNA synthesis at these concentrations. Human alpha 1-proteinase inhibitor, previously demonstrated to be an inhibitor of fibroblast proliferation, was also mitogenic at concentrations lower than those which inhibited proteolytic activity and cell proliferation. Human pancreatic secretory trypsin inhibitor and epidermal growth factor apparently work through independent mechanisms, since their mitogenic effects are additive.

Endoscopic palliation of malignant obstructive jaundice

Patients referred for endoscopic retrograde cholangiopancreatography (ERCP) over a 12 month period who had a diagnosis of malignant obstructive jaundice prior to or confirmed by the procedure were reviewed. Insertion of a biliary endoprosthesis was attempted in 23 out of 26 patients and was successful in 19 (82%). A significant fall in bilirubin was seen in 15 (79%) of those who had a successful procedure. The only early complication was cholangitis in two patients. Late complications were related to occlusion of the endoprosthesis and replacement was required in six patients. Endoscopic palliation of malignant obstructive jaundice is a useful technique and should be considered as the initial procedure in all patients considered to have nonresectable malignancy.

Polymyositis complicating staphylococcal septicaemia

Inflammatory polymyositis can be precipitated by acute febrile illness of viral origin, but similar association with pyogenic bacterial illness is not recognised. We describe two cases in which recovery from staphylococcal septicaemia was complicated by a widespread inflammatory myopathy.

Small intestinal permeability in pediatric clinical practice

Passive permeability of small intestine to lactulose and mannitol was studied in children suspected of having intestinal disease, using a hypertonic differential sugar absorption test. Children with coeliac disease and cows' milk intolerance were shown to have an elevated urinary lactulose/mannitol recovery ratio when compared with controls, children with normal jejunal biopsy, or children in whom alternative explanations for failure to thrive had been demonstrated. The abnormality in permeability ratio principally reflects a reduced urinary recovery of mannitol following oral administration. This study demonstrates that a hypertonic sugar absorption test is well tolerated even by young children, is practicable in routine clinical pediatric practice, and is capable of demonstrating abnormal intestinal function in children with small intestinal disease.

Permeability of the rat small intestine to carbohydrate probe molecules

1. Absorption of carbohydrate probe molecules from ligated loops of rat small intestine was studied. Absorption was determined by measuring recovery of molecules in the urine, corrected for incomplete recovery after intravenous injection, and was examined for correlation with several parameters of molecular dimension. 2. Absorption depended on molecular volume rather than relative molecular mass, molecular radius or molecular area. 3. Molecules with a molecular volume below 225 X 10(-3) nm3 were absorbed to a greater extent than larger molecules, and absorption was affected critically by molecular volume, small changes in volume producing considerable variation in absorption. 4. Absorption of larger molecules was not affected by changes in volume within the range 362 X 10(-3)-1128 X 10(-3) nm3. 5. These findings support the concept that there are at least two aqueous diffusion pathways across the intestinal mucosa. small molecules diffusing through a small channel of finite dimension, compatible with a transcellular aqueous pore, whilst large molecules diffuse through a less frequent pathway of considerably larger dimensions.

Abnormal intestinal permeability. An aetiological factor in chronic psychiatric disorders?

Abnormal intestinal absorption has been suggested as an aetiological factor in schizophrenia. A procedure for investigating intestinal permeability was carried out in a group of chronic psychiatric in-patients. A proportion of the subjects studied showed abnormal intestinal permeability which could not be attributed to established bowel disease. Patients who were receiving neuroleptic but not anticholinergic drugs were those most often showing abnormal intestinal permeability. This work is at an early stage of development but preliminary findings suggest that further investigations should be carried out to establish the circumstances in which changes in intestinal permeability may be associated with mental illness.

Short-term biliary dilatation and stenting in primary sclerosing cholangitis

Operative biliary dilatation and prolonged percutaneous transhepatic biliary stenting have been useful in the management of primary sclerosing cholangitis, both intrahepatic and extrahepatic biliary strictures regressing after 12-16 months of treatment. We report the results of less prolonged treatment in a further four patients, in whom removal of a percutaneous transhepatic biliary stent 3-11 months after treatment led to an improvement in radiological appearances of the extrahepatic bile ducts, with no discernible effect on intrahepatic disease. Extrahepatic stricture recurred rapidly in one patient stented for only 3 months. Operative biliary dilatation and stenting for 5-11 months may lead to regression of extrahepatic biliary strictures in patients with primary sclerosing cholangitis, whereas intrahepatic disease requires stenting for 12-16 months. Further study is required to determine the applicability of this approach to primary sclerosing cholangitis.

Collagenous colitis associated with small intestinal villous atrophy

Two patients diagnosed as having small intestinal hyperplastic villous atrophy and being treated with a gluten free diet were investigated because of persistent watery diarrhoea. Both were found to have collagenous colitis. Previous reports of this condition have emphasised the presence of normal small intestinal mucosal architecture and the association of collagenous colitis with intestinal villous atrophy has not previously been reported. Both cases responded to oral steroid therapy, but not to other previously recommended treatment regimens.