Role of vesicular nucleotide transporter VNUT (SLC17A9) in release of ATP from AR42J cells and mouse pancreatic acinar cells.

ATP is released from cells in response to various stimuli. Our previous studies on pancreas indicated that pancreatic acini could be major stores of secreted ATP. In the present study, our aim was to establish the role of the vesicular nucleotide transporter (VNUT), SLC17A9, in storage and release of ATP. Freshly prepared acini from mice and AR42J rat acinar cells were used in this study. We illustrate that in AR42J cells, quinacrine (an ATP store marker) and Bodipy ATP (a fluorescent ATP analog) co-localized with VNUT-mCherry to vesicles/granules. Furthermore, in acini and AR42J cells, a marker of the zymogen granule membranes, Rab3D, and VNUT co-localized. Dexamethasone treatment of AR42J cells promoted formation of acinar structures, paralleled by increased amylase and VNUT expression, and increased ATP release in response to cholinergic stimulation. Mechanical stimulus (pressure) and cell swelling also induced ATP release, but this was not influenced by dexamethasone, most likely indicating different non-zymogen-related release mechanism. In conclusion, we propose that VNUT-dependent ATP release pathway is associated with agonist-induced secretion process and downstream purinergic signalling in pancreatic ducts.

Early predictors of the long-term outcome of low back pain--results of a 22-year prospective cohort study.

BACKGROUND: poor outcome of low back pain in patients seen in general practice is related to the pain history, physical impairment and working conditions, at least in short-term follow-ups. We do not know if these findings hold, seen from the perspective of decades. OBJECTIVES: to show if patients consulting the GP for the first time regarding an episode of low back pain have excess poor outcome 22 years later and, if so, whether the best predictors are data based on the symptoms, clinical signs or work history. The design of the study is a 22-year follow-up of an inception cohort of 78 patients with low back pain. The setting of the study is a single general practice in a suburb of Copenhagen, Denmark. METHODS: selected predictors were separated into pain characteristics, clinical signs and indicators related to the work history. Outcome measures were the 1-year period prevalence of low back pain, use of painkillers for low back pain, use of health care providers, impairments due to low back pain and unfitness for work caused by low back pain. The influence of the predictors was assessed by relative risks. RESULTS: after 22 years, four out of five patients still experienced low back pain. The perception of poor working conditions correlates with recurrent low back pain, intake of painkillers and limitations to daily life. CONCLUSION: compared with pain history and clinical findings, the perception of workload is a better predictor of the long-term outcome of low back pain.

Structure-function relationships of Na(+), K(+), ATP, or Mg(2+) binding and energy transduction in Na,K-ATPase.

The focus of this article is on progress in establishing structure-function relationships through site-directed mutagenesis and direct binding assay of Tl(+), Rb(+), K(+), Na(+), Mg(2+) or free ATP at equilibrium in Na,K-ATPase. Direct binding may identify residues coordinating cations in the E(2)[2K] or E(1)P[3Na] forms of the ping-pong reaction sequence and allow estimates of their contributions to the change of Gibbs free energy of binding. This is required to understand the molecular basis for the pronounced Na/K selectivity at the cytoplasmic and extracellular surfaces. Intramembrane Glu(327) in transmembrane segment M4, Glu(779) in M5, Asp(804) and Asp(808) in M6 are essential for tight binding of K(+) and Na(+). Asn(324) and Glu(327) in M4, Thr(774), Asn(776), and Glu(779) in 771-YTLTSNIPEITP of M5 contribute to Na(+)/K(+) selectivity. Free ATP binding identifies Arg(544) as essential for high affinity binding of ATP or ADP. In the 708-TGDGVND segment, mutations of Asp(710) or Asn(713) do not interfere with free ATP binding. Asp(710) is essential and Asn(713) is important for coordination of Mg(2+) in the E(1)P[3Na] complex, but they do not contribute to Mg(2+) binding in the E(2)P-ouabain complex. Transition to the E(2)P form involves a shift of Mg(2+) coordination away from Asp(710) and Asn(713) and the two residues become more important for hydrolysis of the acyl phosphate bond at Asp(369).

Structure-function relationships of E1-E2 transitions and cation binding in Na,K-pump protein.

Fully active Na,K-ATPase and lethal mutations can be expressed in yeast cells in yields allowing for equilibrium ATP binding, occlusion of T1+, K+ displacement of ATP, and Na(+)-dependent phosphorylation with determinations of affinity constants for binding and constants for the conformational equilibria. Removal of the charge and hydrophobic substitution of the phosphorylated residue (Asp369Ala) reveals an intrinsic high affinity for ATP binding (Kd 2.8 vs. 100 nM for wild type) and causes a shift of conformational equilibrium towards the E2 form. Substitution of Glu327, Glu779, Asp804 or Asp808 in transmembrane segments 4, 5, and 6 shows that each of these residues are essential for high-affinity occlusion of K+ and for binding of Na+. Substitution of other residues in segment 5 shows that the carboxamide group of Asn776 is important for binding of both K+ and Na+. Differential effects of the relevant mutations identify Thr774 as specific determinant of Na+ binding in the E1P[3Na] form, whereas Ser775 is a specific participant of high-affinity binding of the E2[2K] form, suggesting that these residues engage in formation of a molecular Na+/K+ switch. The position of the switch may be controlled by rotating or tilting the helix during the E1-E2 transition.

Identification of Asp804 and Asp808 as Na+ and K+ coordinating residues in alpha-subunit of renal Na,K-ATPase.

Mutations to Asp804 and Asp808 in the alpha-subunit almost abolish Na,K-ATPase activity, but high-affinity binding of [3H]ATP or [3H]ouabain at equilibrium and E1-E2 transitions are preserved. Titration of K+-ion displacement of [3H]ATP or [3H]ouabain shows that the mutations interfere with occlusion of K+ in the E2[2K] conformation. Reduced phosphorylation levels or affinities for Na+ in presence of oligomycin indicate that Asp804 and Asp808 also contribute to coordination of Na+ in the E1P[3Na] form. Demonstration of alternate interactions of Na+ or K+ with Asp804 and Asp808 support the notion of cation binding in a ping-pong sequence in catalytic models of Na,K-pumping.

Epidemiology of asthma in Denmark.

The epidemiology of asthma in the Danish population is reviewed with reference to research on asthma in general populations, in general/family practice and in hospitals. The prevalence of asthma in Denmark is on the same order as found in national morbidity studies in Britain and the US. The two-peaked prevalence curve suggests that there are two different diseases: childhood asthma, provoked by allergy and temporarily stopping before adulthood, and adult asthma gradually increasing in prevalence until 60 to 70 years of age and due to hyperreactivity. In Denmark, asthma does not appear to be increasing in incidence. With the exception of the very young, seasonal variation is not pronounced and hyperreactivity is thus more dependent on irritants than on seasonally occurring allergens such as pollen. The concomitant prevalence of asthma and allergic rhinitis was similar to rates reported elsewhere. Problems and limitations of sources of data for epidemiologic studies are discussed.

Container-grown tree seedling responses to sodium chloride applications in different substrates.

Seedlings of Norway maple (Acer platanoides), silver birch (Betula pendula), Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) were grown in selected sodium chloride (NaCl) concentrations, soil types and under different watering regimes. Plants were raised from seeds, except for Scots pine plants which were obtained from a commercial source. Among the plant species tested, Scots pine was the most tolerant to soil salinity, while Norway spruce was the most susceptible. For both Norway maple and Norway spruce some half-sib families were more tolerant than others. No significant correlation was found between the tolerance of different half-sib families and the tolerance of mother trees observed in the field. The extent of leaf necrosis correlated significantly with the leaf concentrations of sodium (Na) and chloride (Cl). Among half-sib families within the species no such correlation was found. On the other hand, the least injured progeny of Norway maples had the highest concentrations of NaCl. The extent of salt-induced leaf necrosis varied with soil type, and a significant interaction between species and soil type was observed. Seedlings of Norway spruce grown in sand showed more severe necrosis and significantly higher concentrations of Na and Cl than seedlings grown in loam, silt loam, and peat. The severity of salt-induced leaf injury varied with the watering regime. Silver birch was the most affected species by drought and autumn watering treatments. Plants of silver birch subjected to drought showed increased leaf necrosis compared to the non-treated plants, and autumn watering treatment reduced the severity of leaf necrosis.

Self-referral and self-payment in Danish primary care.

This study aims at characterizing the group of people who want to have the right to consult any general practitioner or practising specialist without referral on condition of part self-payment, as opposed to the group of people who choose to be registered with a general practice that offers free services but controls further access to the health care system. All adults or a 10% sample of those listed in nationwide Danish registers were examined cross-sectionally for social and demographic factors and utilization of primary and secondary health care. A minority, which totals 3% of the population, chose free choice of doctor and part self-payment. On average, this group is older and has a higher income. Its mortality and its utilization of general practice and hospital services are lower, and its use of practising specialists is higher, than the majority. Among the persons who chose free choice and self-payment, the pattern of utilization is more likely to be due to a wish for free choice and for specialized medical care than to high morbidity. Dissatisfaction caused by restrictions on self-referral to specialists can be met by offering an option of a parallel system of free choice of doctor on condition of part self-payment.

Randomised controlled trial of structured personal care of type 2 diabetes mellitus.

OBJECTIVE: To assess the effect of a multifaceted intervention directed at general practitioners on six year mortality, morbidity, and risk factors of patients with newly diagnosed type 2 diabetes. DESIGN: Pragmatic, open, controlled trial with randomisation of practices to structured personal care or routine care; analysis after 6 years. SETTING: 311 Danish practices with 474 general practitioners (243 in intervention group and 231 in comparison group). PARTICIPANTS: 874 (90.1%) of 970 patients aged >/=40 years who had diabetes diagnosed in 1989-91 and survived until six year follow up. INTERVENTION: Regular follow up and individualised goal setting supported by prompting of doctors, clinical guidelines, feedback, and continuing medical education. MAIN OUTCOME MEASURES: Predefined clinical non-fatal outcomes, overall mortality, risk factors, and weight. RESULTS: Predefined non-fatal outcomes and mortality were the same in both groups. The following risk factor levels were lower for intervention patients than for comparison patients (median values): fasting plasma glucose concentration (7.9 v 8.7 mmol/l, P=0.0007), glycated haemoglobin (8.5% v 9.0%, P<0.0001; reference range 5.4-7.4%), systolic blood pressure (145 v 150 mm Hg, P=0.0004), and cholesterol concentration (6.0 v 6.1 mmol/l, P=0.029, adjusted for baseline concentration). Both groups had lost weight since diagnosis (2.6 v 2.0 kg). Metformin was the only drug used more frequently in the intervention group (24% (110/459) v 15% (61/415)). Intervention doctors arranged more follow up consultations, referred fewer patients to diabetes clinics, and set more optimistic goals. CONCLUSIONS: In primary care, individualised goals with educational and surveillance support may for at least six years bring risk factors of patients with type 2 diabetes to a level that has been shown to reduce diabetic complications but without weight gain.

Changing remuneration systems: effects on activity in general practice.

OBJECTIVE: To investigate the effects on general practitioners' activities of a change in their remuneration from a capitation based system to a mixed fee per item and capitation based system. DESIGN: Follow up study with data collected from contact sheets completed by general practitioners in one period before (March 1987) a change in their remuneration system and two periods after (March 1988, November 1988), with a control group of general practitioners with a mixed fee per item and capitation based system throughout. SETTING: General practices in Copenhagen city (index group) and Copenhagen county (control group). SUBJECTS: 265 General practitioners in Copenhagen city, of whom 100 were selected randomly from the 130 who agreed to participate (10 exclusions) and 326 general practitioners in Copenhagen county. MAIN OUTCOME MEASURES: Number of consultations (face to face and by telephone) and renewals of prescriptions, diagnostic and curative services, and specialist and hospital referrals per 1000 enlisted patients in one week. RESULTS: Of the 75 general practitioners who completed all three sheets, four were excluded for incomplete data. Total contact rates per 1000 patients listed rose significantly compared with the rates before the change index in the city (100.0 before the change v 111.7 (95% confidence interval 106.4 to 117.4 after the change) and over the same time in the control group (100.0 v 106.0), but within a year these rates fell (to 104.2(99.1 to 109.6) and 104.0 respectively). There was an increase in consultations by telephone initially but not thereafter. Rates of examinations and treatments that attracted specific additional remuneration after the change rose significantly compared with those before (diagnostic services, 138.1 (118.7 to 160.5) and 159.5 (137.8 to 184.7) and curative services 194.6 (152.2 to 248.9) and 194.8(152.3 to 249.2) for second and third data collections respectively) and with the control group (diagnostic services 105.3, 107.6 and curative services 106.0, 115.0) whereas referral rates to secondary care fell (specialist referrals 90.1 (80.7 to 100.6) and 77.0 (68.6 to 86.4) and hospital referrals 87.4 (71.1 to 107.5) and 68.4 (54.7 to 85.4] in doctors in the city. CONCLUSIONS: Introducing a partial fee for service system seemed to stimulate the provision of services by general practitioners, resulting in reduced referral rates. The concept of a "target income" which doctors aim at, rather than maximising their income seemed to play a part in adjustment to changing the system of remuneration.

[Increasing asthma mortality in Denmark 1969-1988. Not because of changed coding practices]. / Stigende astmadødelighed i Danmark 1969-1988. Ikke på grund af oendret kodepraksis.

We have studied asthma mortality in Denmark from 1969 to 1988. Age standardized mortality rates calculated in three age groups, 10-34, 35-59, and > 60 years, disclosed similar trends. Increasing mortality from asthma in the mid-1970s to 1988 was seen in all three age groups with higher mortality in 1979-1988 as compared with 1969-1978 of 95%, 55%, and 69%, respectively. Since the eighth revision of the International Classification of Diseases (ICD-8) was used in Denmark over the entire 20-year period, changes in coding practice due to change of classification system cannot explain the findings.

[Epidemiologic study of persons having group 2 insurance in Denmark. 2. Utilization of the health services among persons insured in groups 1 and 2]. / En epidemiologisk undersøgelse af de gruppe 2 sikrede i Danmark. 2. Brug af sundhedsvaesenet blandt personer i sygesikringens gruppe 1 og 2.

Persons insured in Group 2 constitute only approximately 4% of the total number of persons insured. In contrast to the approximately 96% of the population insured in Group 1, persons insured in Group 2 are ensured free choice of general practitioner and practising specialists from time to time on payment of partial payment of the doctor's bill. Group 2 insured persons make less use of assistance from the general practitioner than persons in Group 1. On the other hand, persons in Group 2 make much more use of assistance from practising specialists. Persons in Group 2 thus substitute specialist help for help from the general practitioner. This holds particularly true for the specialties gynaecology and medicine. An age-subdivided analysis of the differences between the utilization of hospital services by the two insurance groups shows that persons insured in Group 2 have lower rates of hospitalization and briefer periods of hospitalization than persons insured in Group 1. A review of the utilization of health services by the two health insurance groups supports the theory that persons in insurance Group 2 are, on the whole, relatively healthy persons with a relatively high demand for the level of service of health treatment.

[Epidemiologic study of persons having group 2 insurance in Denmark. 1. Historical development, social and demographic differences between health insurance groups 1 and 2]. / En epidemiologisk undersøgelse af de gruppe 2 sikrede i Danmark. 1. Den historiske udvikling. Sociale og demografiske forskelle imellem sygesikringsgruppe 1 og 2.

The majority of adults in Denmark can choose between the forms of health insurance 1 and 2. Persons insured in Group 2, on payment of a premium, obtain certain perquisites as compared with Group 1, primarily they may consult general practitioners and specialists of their own choice. Since the introduction of the Health Insurance Law in 1976, the number of persons insured in Group 2 has decreased to 3.8% of those insured in 1988. More than 3/4 of these have been insured in Group 2 since 1976. The number of new group 2 insured persons has remained relatively stable at about 3,000 persons per annum. The average age in Group 2 is 58.3 years as compared with 45.0 years in Group 1. 60% live in the region of the capital. The number of economically and socially well established persons in Group 2 is markedly higher than in Group 1, particularly in the higher age groups where the mortality in Group 2 insured persons is considerably lower than in Group 1 insured persons.

[Diagnosis and treatment in general practice. 5. Attitudes of general practitioners--a review]. / Diagnostik og behandling i almen praksis. 5. Praktiserende laegers holdninger--en oversigt.

The word "attitude" means continuing orientation of the individual towards the world. Attitudes consist of cognitive beliefs and affective reactions, which predispose the individual towards certain action patterns and which have emotional (positive/negative) value. Doctors' attitudes are developed by the joint influences of selection and socialization. Doctors are predominantly recruited from the middle classes and are therefore characterized by middle class attitudes, valuing hard work, activity, self-discipline and rationality. The curriculum of medical school has a further and independent influence on the personalities of physicians-to-be, shaping their attitudes towards patients and medical work. This study gives a review of the official professional ideology of general practitioners (GP's) which, in some respects, differs from the ideology of other doctors. The basic issues, according to general practitioners' commission reports, textbooks, and research can be subdivided into four main principles: 1. A holistic model of disease, 2. The GP as a family doctor (a continuous and personal doctor-patient relationship), 3. The GP as a "gate-keeper" (the central referring role), 4. General practice as a "free enterprise". The two first principles deal with the substance of the GP's work and they stress holism, continuity and dialogue. The two last principles on the other hand deal with the structure of GP's work, stressing freedom and power. Thus general practitioners' ideology and attitudes serve to emphasize differences between hospital medicine and general practice. Differentiation between GP roles and roles of their psycho-social co-workers in the primary health care is not equally marked. Demarcation of general practice ideology in this respect is needed.

[Randomized controlled trial of structured, individualized treatment of type 2 diabetes mellitus. The project of Diabetes Care in General Practice]. / Randomiseret kontrolleret undersøgelse af struktureret, individualiseret behandling af type 2-diabetes mellitus. Projektet Diabetesomsorg i almen praksis.

INTRODUCTION: We assessed the effect of a multifaceted intervention directed at general practitioners to improve type 2 diabetes care. MATERIALS AND METHODS: Three hundred and eleven Danish practices with 474 general practitioners were randomised to structured personal care (intervention group) or routine care (comparison group). Of 970 surviving patients (aged 40+ years) diagnosed with diabetes in 1989-1991, 874 (90.1%) were assessed after 6 years. Intervention comprised regular follow-up and individualized goal-setting, supported by reminders to doctors, clinical guidelines, feed-back, and continuing medical education. RESULTS: Predefined non-fatal outcomes and mortality were the same in both groups. The following risk factor levels were lower in the intervention patients than in the comparison patients: fasting plasma glucose (7.9 vs 8.7 mmol/l, medians, P = 0.0007), haemoglobin A1c (8.5 vs 9.0%, P < 0.0001, normal range 5.4-7.4%), systolic blood pressure (145 vs 150 mmHg, P = 0.0004), and cholesterols (6.0 vs 6.1 mmol/l, P = 0.029, baseline-adjusted). Both groups had sustained a weight loss since diagnosis (2.6 vs 2.0 kg). Metformin was the only drug used more frequently in the intervention group (24 vs 15%). Intervention doctors arranged more follow-up consultations, referred fewer patients to diabetes clinics, and were more optimistic in their goal-setting. DISCUSSION: In primary care, individualized goal-setting with educational and surveillance support may for at least six years bring risk factors of patients with type 2 diabetes to a level that in other trials has been shown to reduce diabetic complications, but without adverse weight gain.

[Individual registration of children in the national health service. New possibilities for epidemiological research in primary health care]. / Eget sygesikringsbevis til børn. Nye muligheder for epidemiologisk forskning i den primaere sundhedssektor.

Since January 1st 1996 all Danish citizens, children included, have been recorded individually in The National Health Service Register (SSR). Services rendered to children are no longer registered with an adult person. This article describes the implementation of this new arrangement. The part of health services to children recorded under an adult personal identification number is getting asymptotically closer to a minimum of about four percent, which is determined by the average time of naming of children. After the introduction of individual registration of children the SSR has improved considerably as a basis for epidemiological studies in Danish primary care.

[Diagnosis and treatment in general practice. Referral courses over a period of 1 year]. / Diagnostik og behandling i almen praksis. Kontaktforløb af helbredsproblemer over 1 år.

This study examined episodes of medical care in five practices, representing a number of municipalities in The Copenhagen County. For comparison of results, data from a similar survey from a 55 practices' study by Hollnagel et al were also used. In these two surveys all encounters were recorded, over period of one year and three months, respectively, each time a health problem or condition was presented to the general practitioner following a personal, telephone or written contact between the patient, or other person representing the patient, and physician. The study population analyzed here consists of 189 and 2,293 adults respectively, who were all registered as group 1 members of the Danish National Health Care system. The date and nature of each contact were registered, including information of the date of any previous contact concerning the same health problem, so that the contacts could be chronicled into episodes of medical care. In addition, detailed data concerning encounter form, reason for encounter, patient's expressed whished to obtain specific services, general practitioners treatment including referrals, and diagnosis were recorded. Compared with the study covering a period of three months, the data covering a period of one year include episodes which represent a larger fraction of the study population in all age groups, 85-95% compared with 55-68%. Similarly a greater number of contacts in the episodes with a total of more than one contact are recorded over a period of one year especially concerning the episodes in the age group 45-64 years of age and the group over 65 years.

[Diagnosis and treatment in general practice. I. The course of illness in primary health service]. / Diagnostik og behandling i almen praksis. 1. Forløbsundersøgelser i den primaere sundhedstjeneste.

The purpose of this review is to present an outline of the use of the unifying concepts of "episodes of medical care" and "episodes of illness" in recent research. The review focuses on theoretical and methodical problems connected with the use of these concepts in research related to general practice. The concept of "episodes of medical care" has been accepted as a valid and useful method of clustering discrete units of services into cohesive entities in previous literature. The concept of "episodes of illness" is, on the other hand, not yet fully defined and further development of this concept is suggested in the paper. The major methodical problem in connection with the use of these concepts is how to define when an episode starts and ends. Three typical examples on how research workers have dealt with this problem are presented and the consequences their choice of definitions have on the results from such studies are outlined. The concept of "episodes of medical care" has hitherto been used mostly in various utilization and morbidity studies in the primary health care sector and psychiatry. In the last decade the concept has also been used especially in American research in connection with studies focussing on the performance of medical care systems. The concept of "episodes of illness" has only been used in connection with relatively few population studies.

[Diagnosis and treatment in general practice. 2. Episodes of medical care of health problems during a period of 3 months]. / Diagnostik og behandling i almen praksis. 2. Kontaktforløb af helbredsproblemer over 3 måneder.

The object of this article is to describe the working process in general practice. One hundred general practices were selected at random in the County of Copenhagen. Fifty-five general practices participated and registered the contacts during the period 13.9.1982 and the next three months for a random sample of group I patients from the low income group of the Danish Health Insurance and born on the 13th of a month. Where each contact is concerned, the individual health problems were registered together with the form of contact, the reason for contact, the wishes of the patient and the doctor's actions and also the diagnosis. Thirty-six % of the low income insurance group men and 37% of the women had at least one contact with general practice in the course of the three-month period. Seventy-nine episodes of medical care per 100 persons were found in a period of investigation of three months and women had nearly twice as many episodes of medical care as the men. In 59% of the episodes of medical care, the patients had at least one symptom. In 22% of the episodes of medical care, the patients were referred to other persons or instances. In 73% of the episodes of medical care, the general practitioner established the final diagnosis.

[Diagnosis and treatment in general practice. 3. Reasons for contact and diagnoses in episodes of medical care]. / Diagnostik og behandling i almen praksis. 3. Kontaktårsager og diagnoser ved kontaktforløb i almen praksis.

The object of this article is to describe the reasons for contact and the diagnoses in general practice by following the course of health problems in a random sample of patients (group 1 in the National Health Insurance System) for three months. In 55 general practices in the County of Copenhagen, all contacts concerning a given health problem in the single individuals were registered. This totalled 1,974 episodes of medical care in approximately 1,200 persons who formed 47% of the random sample. This investigation assessed the various classifications of reasons for encounter with primary health care as regards employability for central coding, information value and agreement with the general medical disease model. Employing the Reason for Visit Classification (USA) supplemented by classifications elaborated by the authors, three dimensions of the concept of "reasons for encounter" could be described: symptoms, the patient's wishes for contact with the doctor and reasons for the current problem. Health problems are described as episodes of one or more contacts. In single-contact episodes, the symptoms and diagnoses are most frequently those of respiratory diseases whereas multi-contact episodes are most frequently found where musculo-skeletal diseases are concerned. It is concluded that a multi-dimensional description of the reasons for contact and a description of the disease pattern on the basis of episodes of medical care can provide more differentiated knowledge about health problems in general practice.