Kassenwechsel und Risikostrukturausgleich in der gesetzlichen Krankenversicherung - empirische Befunde der Kooperativen Gesundheitsforschung in der Region Augsburg (KORA)

Since 1996, all citizens of the Federal Republic of Germany who are insured in the statutory health insurance system are entitled to switch their sickness fund. The rationale of this regulation was to strengthen elements of competition in this system in order to stimulate the sickness funds to improve the efficiency of health care and to respond to consumers' preferences. Simultaneously, to avoid the implicit incentives for sickness funds to engage in risk selection, a risk compensation mechanism was introduced, including as morbidity-related risk adjusters age, sex and incapacity to work. Based on the KORA survey S4 (1999/2001) we take the case of switching behaviour in the region of Augsburg, and analyse whether this risk adjustment scheme was working effectively. The results show that persons changing their sickness fund were characterised by a comparatively smaller burden of chronic diseases and by a less frequent utilization of inpatient health care. Under these conditions, differences in the contribution rates do not accurately reflect differences in the performance and efficiency of sickness funds. Moreover, the migration of good risk to sickness funds with favourable contribution rates threatens the principle of financial solidarity. Therefore, the system of risk equalisation has to be developed towards measuring the risk volume borne by the sickness funds more precisely than hitherto.

Oral health care in the elderly population in Malaysia--a review

One of the undeniable facts about living is that everyday we are getting older. By 2050, it is projected that one out of every five Malaysians will be 60 or older. The economic challenge of this demographic change will affect development and the financial implications of sustaining well being of this group are formidable and complex. This population group has extensive oral disease, medical problems that complicate their oral care, and unique dental treatment challenges. The authors discuss the problem of oral healthcare among the aged, its impediments and propose some approaches for improvement to better serve the needs of this group of vulnerable members of our nation.

Treatment with immunosuppressive and anti-inflammatory agents delays onset of canine genetic narcolepsy and reduces symptom severity

All Doberman pinschers and Labrador retrievers homozygous for a mutation of the hypocretin (orexin) receptor-2 (hcrtr2) gene develop narcolepsy under normal conditions. Degenerative changes and increased display of major histocompatibility complex class II antigens have been linked to symptom onset in genetically narcoleptic Doberman pinschers. This suggests that the immune system may contribute to neurodegenerative changes and narcoleptic symptomatology in these dogs. We therefore attempted to alter the course of canine genetic narcolepsy, as an initial test of principle, by administering a combination of three immunosuppressive and anti-inflammatory drugs chosen to suppress the immune response globally. Experimental dogs were treated with a combination of methylprednisolone, methotrexate and azathioprine orally starting within 3 weeks after birth, and raised in an environment that minimized pathogen exposure. Symptoms in treated and untreated animals were quantified using the food elicited cataplexy test (FECT), modified FECT and actigraphy. With drug treatment, time to cataplexy onset more than doubled, time spent in cataplexy during tests was reduced by more than 90% and nighttime sleep periods were consolidated. Short-term drug administration to control dogs did not reduce cataplexy symptoms, demonstrating that the drug regimen did not directly affect symptoms. Treatment was stopped at 6 months, after which experimental animals remained less symptomatic than controls until at least 2 years of age. This treatment is the first shown to affect symptom development in animal or human genetic narcolepsy. Our findings show that hcrtr2 mutation is not sufficient for the full symptomatic development of canine genetic narcolepsy and suggest that the immune system may play a role in the development of this disorder.

Activity of dorsal raphe cells across the sleep-waking cycle and during cataplexy in narcoleptic dogs

Cataplexy, a symptom associated with narcolepsy, represents a unique dissociation of behavioural states. During cataplectic attacks, awareness of the environment is maintained, as in waking, but muscle tone is lost, as in REM sleep. We have previously reported that, in the narcoleptic dog, noradrenergic cells of the locus coeruleus cease discharge during cataplexy. In the current study, we report on the activity of serotonergic cells of the dorsal raphe nucleus. The discharge patterns of serotonergic dorsal raphe cells across sleep-waking states did not differ from those of dorsal raphe and locus coeruleus cells recorded in normal rats, cats and monkeys, with tonic discharge in waking, reduced activity in non-REM sleep and cessation of activity in REM sleep. However, in contrast with locus coeruleus cells, dorsal raphe REM sleep-off neurones did not cease discharge during cataplexy. Instead, discharge continued at a level significantly higher than that seen in REM sleep and comparable to that seen in non-REM sleep. We also identified several cells in the dorsal raphe whose pattern of activity was the opposite of that of the presumed serotonergic cells. These cells were maximally active in REM sleep and minimally active in waking and increased activity during cataplexy. The difference between noradrenergic and serotonergic cell discharge profiles in cataplexy suggests different roles for these cell groups in the normal regulation of environmental awareness and muscle tone and in the pathophysiology of narcolepsy.

Successful use of oral linezolid as a single active agent in endocarditis unresponsive to conventional antibiotic therapy

Treatment of resistant gram-positive endocarditis is difficult. We report a case of resistant Staphylococcus epidermidis endocarditis that failed to respond to conventional antibiotic therapy but was treated successfully with an oral regimen of a new antibiotic, linezolid as a single active agent. This case report demonstrates the use of linezolid as an effective alternative to conventional antibiotics in such cases.

A randomized phase II trial of SRL172 (Mycobacterium vaccae) +/- low-dose interleukin-2 in the treatment of metastatic malignant melanoma

We conducted a randomized phase II trial of SRL172 (Mycobacterium vaccae) +/- low-dose interleukin-2 (IL-2) as treatment for stage IV malignant melanoma. The objectives were to establish the safety and efficacy of SRL172 with and without IL-2. All patients had measurable metastatic disease and none received concurrent chemotherapy, radiotherapy, corticosteroids or any other investigational agent. Sixteen patients were randomized into each arm of the trial prior to closure. The trial was halted prematurely when no responses were seen in the first 16 patients receiving SRL172 alone, predicting a response rate of less than 20%. Three partial remissions were seen in the 16 patients receiving SRL172 + IL-2. These patients remained on monthly SRL172 + IL-2, with disease progression at 12, 15 and 23 months. They continued on the trial regimen following surgical management of their disease progression. This trial provides preliminary evidence of a new, non-toxic, immunotherapeutic regimen in the management of malignant melanoma. Further trials are required to establish a definitive response rate and to compare the combination regimen with the regimen of low-dose IL-2 used in this trial. A biological basis for the responses seen in the SRL172 + IL-2 arm also needs to be established.

Genetic variation of varicella-zoster virus: evidence for geographical separation of strains

Heteroduplex mobility assay was used to identify variants of varicella-zoster virus (VZV) circulating in the United Kingdom and elsewhere. Forty variable positions were identified. Sixteen substitutions were non-synonymous, resulting in an amino acid change, the majority of which were clustered within surface expressed proteins. Phylogenetic analysis distinguished at least three major clades (strains A, B, C) supported by significant bootstrap values. Apart from the United Kingdom and Brazil where all three strains were found, genotypes appeared to be closely associated with the geographical region in which they were sampled. Allelic co-segregation of widely spaced single nucleotide polymorphisms (SNPs) confirmed the genetic stability of the VZV. Recombination rates were difficult to calculate because of the low intra genotypic variation. However, one haplotype originating from Brazil is most parsimoniously explained as a recombinant between A and C strains, which co-occur in the region. Two further UK strains appeared to be recombinants between groups B and C.

Hypocretin release in normal and narcoleptic dogs after food and sleep deprivation, eating, and movement

Hypocretins (orexins) are recently discovered hypothalamic neuropeptides that have been implicated in the etiology of narcolepsy. The normal behavioral functions of these peptides are unclear, although a role in feeding has been suggested. We measured hypocretin-1 (Hcrt-1) in the cerebrospinal fluid of dogs during a variety of behaviors. We found that 48 h without food (24 h beyond normal 24-h fasting period) produced no significant change in Hcrt-1 levels nor did feeding after the deprivation. In contrast, 24 h of sleep deprivation produced on average a 70% increase in Hcrt-1 level compared with baseline levels. The amount of increase was correlated with the level of motor activity during the sleep-deprivation procedure. A 2-h period of exercise in the same dogs produced a 57% increase in Hcrt-1 levels relative to quiet waking levels, with the magnitude of the increase being highly correlated with the level of motor activity. The strong correlation between motor activity and Hcrt-1 release may explain some of the previously reported behavioral, physiological, and pathological phenomena ascribed to the Hcrt system.

Renal trauma secondary to stab, blunt and firearm injuries--a 5-year study

OBJECTIVE

To review our experience of renal trauma at King Edward VIII Hospital, Durban.

DESIGN

Retrospective study over 5 years.

SETTING

Tertiary referral hospital in an urban area.

PATIENTS

One hundred and seventy-four patients presenting with renal injuries treated at King Edward VIII Hospital.

INTERVENTIONS

One hundred and thirty-six patients underwent laparotomy, while 38 were managed conservatively.

RESULTS

There were 174 patients with renal injuries (148 male, median age 26 years). Eighty-seven injuries were from firearms, 43 from stabs and 44 from blunt trauma. Of 136 patients who underwent surgery, 60 were managed conservatively at laparotomy, 26 underwent renorrhaphy, 40 nephrectomy and 10 heminephrectomy. There was a 33% complication rate following surgery. The mortality rate was 20% (24%, 21% and 12% for firearm, stab and blunt injuries, respectively). There was no statistically significant difference in mortality for firearm, stab and blunt injuries. Furthermore, there was no difference in mortality and morbidity between those with associated organ injuries and those with isolated injuries (29% v. 21% and 30% v. 16%, respectively), but the difference in mortality became significant when patients with isolated injuries who did not undergo surgery were included (P = 0.0083).

CONCLUSION

Renal injuries either in isolation or in association with other injuries carry a high mortality and morbidity rate. Firearm injury patients have a large number of associated injuries and have the highest complication rate. Operative strategy should be conservative unless the kidney is unsalvageable.

Systemic administration of hypocretin-1 reduces cataplexy and normalizes sleep and waking durations in narcoleptic dogs

Recent work has implicated the hypocretin (orexin) system in the genesis of narcolepsy. In the current study we demonstrate that systemically administered hypocretin-1 (Hcrt-1) produces an increase in activity level, longer waking periods, a decrease in REM sleep without change in nonREM sleep, reduced sleep fragmentation and a dose dependent reduction in cataplexy in canine narcoleptics. Repeated administration of single daily doses of Hcrt-1 led to consolidation of waking and sleep periods and to a complete loss of cataplexy for periods of three or more days after treatment in animals that were never asymptomatic under control conditions. Systemic administration of Hcrt-1 may be an effective treatment for narcolepsy.

Flexural strength of heat-polymerized polymethyl methacrylate denture resin reinforced with glass, aramid, or nylon fibers

STATEMENT OF PROBLEM

Despite the favorable properties of conventional PMMA used as a denture base material, its fracture resistance could be improved.

PURPOSE

This in vitro study was performed to determine whether the flexural strength of a commercially available, heat-polymerized acrylic denture base material could be improved through reinforcement with 3 types of fibers.

MATERIAL AND METHODS

Ten specimens of similar dimensions were prepared for each of the 4 experimental groups: conventional acrylic resin and the same resin reinforced with glass, aramid, or nylon fibers. Flexural strength was evaluated with a 3-point bending test. The results were analyzed with a 1-way analysis of variance.

RESULTS

All reinforced specimens showed better flexural strength than the conventional acrylic resin. Specimens reinforced with glass fibers showed the highest flexural strength, followed by aramid and nylon.

CONCLUSION

Within the limitations of this study, the flexural strength of heat-polymerized PMMA denture resin was improved after reinforcement with glass or aramid fibers. It may be possible to apply these results to distal extension partial denture bases and provisional fixed partial dentures.

Does aspirin attenuate the effect of angiotensin-converting enzyme inhibitors in hypertension or heart failure?

There is a wealth of data that suggests an important interaction between aspirin and angiotensin-converting enzyme inhibitors in patients with chronic stable cardiovascular disease. The interaction is less obvious in the postinfarction setting, possibly reflecting the fact that many patients stop their aspirin therapy within a few months of such an event. An interaction is biologically plausible, because there is considerable evidence that angiotensin-converting enzyme inhibitors exert important effects through increasing the production of vasodilator prostaglandins, whereas aspirin blocks their production through inhibition of cyclooxygenase, even at low doses. There is some evidence that low-dose aspirin may raise systolic and diastolic blood pressure. There is also considerable evidence that aspirin may entirely neutralize the clinical benefits of angiotensin-converting enzyme inhibitors in patients with heart failure. In addition, aspirin may have an adverse effect on outcome in patients with heart failure that is independent of any interaction with angiotensin-converting enzyme inhibitors, possibly by blocking endogenous vasodilator prostaglandin production and enhancing the vasoconstrictor potential of endothelin. The evidence is not sufficient to justify advising long-term aspirin therapy for patients with cardiovascular disease in general, and for those with heart failure in particular. Thus, the lack of evidence of benefit with aspirin in patients with heart failure and coronary disease, along with growing evidence that aspirin is directly harmful in patients with heart failure and that aspirin may negate the benefits of angiotensin-converting enzyme inhibitors suggest that, unless there is an opportunity to randomize the patient into a study of antithrombotic strategies, then aspirin should be withdrawn or possibly substituted with an anticoagulant or an antiplatelet agent that does not block cyclooxygenase. In contrast, there is fairly robust evidence for a benefit of both aspirin and angiotensin-converting enzyme inhibitors during the first 5 weeks after a myocardial infarction, with little evidence of an interaction. The combination of aspirin and angiotensin-converting enzyme inhibitors is warranted during this period, after which discontinuation or substitution of aspirin with another agent should be considered.

Therapeutic ultrasound for chronic total coronary artery occlusions

This article focuses on the use of catheter-delivered ultrasound as a device for treatment of coronary arterial total occlusion (CTO). The standard treatment of CTO is reviewed and serves as the basis for the need for new treatment options, such as catheter-delivered ultrasound (SONICROSS). The results of FDA-approved Phase I and Phase II clinical trials using SONICROSS for refractory CTO are described. The Phase II trials indicate that the SONICROSS-facilitated guidewire passage in 71% of CTOs are otherwise refractory to guidewire passage. However, at present, the SONICROSS catheter system is limited in its ability to be delivered reliably to the CTO because of catheter size and trackability.

[Current research perspectives of health system research and health economics in Germany]

The German statutory health insurance scheme is confronted with a steadily rapid progress of medical sciences and increasing difficulties to mobilize the financial resources necessary for applying the new scientific knowledge in health care. Therefore it is absolutely imperative to intensify the efforts to improve the effectiveness and efficiency of health care. Health policies based on health targets, the development of patterns requiring integrated care, redefining the bunch of health insurance benefits, and a more regular use of methods of economic evaluation have been proposed as promising approaches towards optimizing resource allocation in health care. However, an analysis of these approaches demonstrates that a valid appraisal of their potential to improve the effectiveness and efficiency of health care requires further research. In addition, European integration may produce tendencies towards a convergence of the national health care systems; this makes it rather difficult to assess how the room for autonomous national health policies will develop in the future.

What is the optimal medical management of ischaemic heart failure?

Ischaemic heart disease is probably the most important cause of heart failure. All patients with heart failure may benefit from treatment designed to retard progressive ventricular dysfunction and arrhythmias. Patients with heart failure due to ischaemic heart disease may also, theoretically, benefit from treatments designed to relieve ischaemia and prevent coronary occlusion and from revascularisation. However, there is little evidence to show that effective treatments, such as angiotensin converting enzyme (ACE) inhibitors and beta-blockers, exert different effects in patients with heart failure with or without coronary disease. Moreover, there is no evidence that treatment directed specifically at myocardial ischaemia, whether or not symptomatic, or coronary disease alters outcome in patients with heart failure. Some agents, such as aspirin, designed to reduce the risk of coronary occlusion appear ineffective or harmful in patients with heart failure. There is no evidence, yet, that revascularisation improves prognosis in patients with heart failure, even in patients who are demonstrated to have extensive myocardial hibernation. On current evidence, revascularisation should be reserved for the relief of angina. Large-scale, randomised controlled trials are currently underway investigating the role of specific treatments targeted at coronary syndromes in patients who have heart failure. The CHRISTMAS study is investigating the effects of carvedilol in a large cohort of patients with and without hibernating myocardium. The WATCH study is comparing the efficacy of aspirin, clopidogrel and warfarin. The HEART-UK study is assessing the effect of revascularisation on mortality in patients with heart failure and myocardial hibernation. Smaller scale studies are currently assessing the safety and efficacy of statin therapy in patients with heart failure. Only when the results of these and other studies are known will it be possible to come to firm conclusions about whether patients with heart failure and coronary disease should be treated differently from other patients with heart failure due to left ventricular systolic dysfunction.

A review of Hib epidemiology in Asia

Meningitis due to an invasive Haemophilus influenzae type b (Hib) infection, has been previously perceived to be relatively uncommon in Asia. However, the incidence of disease and its impact may have been underestimated. In addition to a lack of microbiological facilities in some hospitals, difficulties in culturing the organism and the widespread use of antibiotics may have hidden the true incidence of the disease in some countries. Furthermore, the reported disease burden probably underestimates the incidence of Hib pneumonia. The epidemiology of invasive Hib disease for various Asian nations is reviewed in this paper. Hospital-based studies show that Hib is a major cause of bacterial meningitis and/or pneumonia in the Philippines, India, Thailand, Malaysia, Indonesia and Vietnam. Singapore and Hong Kong have a low incidence of infection compared with Western and other Asian nations. This low incidence is not due to a higher level of natural protective antibodies, but may be related to an interaction between environmental and genetic factors. Therefore the widespread belief that Hib infection is unimportant in Asia does not refer to Asia as a whole and possibly to Chinese patients only, and failure to recognize this has serious implications. The inclusion of Hib vaccine in the routine infant immunization schedule in many industrialized nations has significantly reduced the incidence of invasive disease. Recent studies have shown Hib vaccination is also effective in preventing invasive disease in children in developing countries. While population-based data may be required to confirm the need for public-funded infant Hib immunization in Asia, its introduction in countries with a high incidence of Hib meningitis and/or pneumonia has the potential to significantly improve pediatric health and survival.

cis-Active elements of Friend spleen focus-forming virus: from disease induction to disease prevention

The polycythemic strain of the Friend spleen focus-forming virus (SFFVp) is a replication-defective, acutely transforming retrovirus inducing a bistage erythroleukemia in susceptible mice. The first stage of the disease is an acute polyclonal erythroblastosis induced by the proliferation-promoting effect of gp55. gp55 is expressed from a spliced subgenomic message of SFFVp and stimulates the cellular receptor for erythropoietin. Using a selectable SFFVp that otherwise mimics the specificity of the disease, we demonstrate that the kinetics of the polyclonal expansion depends on the transcriptional strength of the retroviral cis-active elements. By exchanging gp55 for apathogenic genes, we show that SFFVp enhancer and splice signals can be successfully utilized for the development of retroviral vectors mediating very efficient transgene expression in hematopoietic cells. Apathogenic selectable SFFVp-based vectors carrying distinct enhancer alterations are a valuable tool to analyze transcriptional control of leukemia viruses in the absence of oncogenic proteins. Moreover they might have therapeutic potential.

Equity in the delivery of health care in Europe and the US

This paper presents a comparison of horizontal equity in health care utilization in 10 European countries and the US. It does not only extend previous work by using more recent data from a larger set of countries, but also uses new methods and presents disaggregated results by various types of care. In all countries, the lower-income groups are more intensive users of the health care system. But after indirect standardization for need differences, there is little or no evidence of significant inequity in the delivery of health care overall, though in half of the countries, significant pro-rich inequity emerges for physician contacts. This seems to be due mainly to a higher use of medical specialist services by higher-income groups and a higher use of GP care among lower-income groups. These findings appear to be fairly general and emerge in countries with very diverse characteristics regarding access and provider incentives.

Abnormal signal-averaged electrocardiogram (SAECG) in obesity

OBJECTIVE

The occurrence of small high-frequency electrocardiogram (ECG) potentials (1 to 20 microV) seen at the end of the QRS complex and into the ST segment have been correlated with increased risk for ventricular arrhythmias and sudden cardiac death. Computer-assisted analysis of these "late potentials" by signal-averaged electrocardiography (SAECG) has been studied and utilized to predict the likelihood of ventricular arrhythmias in various clinical states. Obesity is associated with significant cardiovascular morbidity and sudden death. Ventricular arrhythmias are postulated causes. We studied the occurrence of late potentials in a randomly selected group of obese patients and healthy volunteers.

RESEARCH METHODS AND PROCEDURES

We performed SAECG on 105 subjects. Of these, 62 were obese ambulatory patients with body mass index (BMI) of >30 kg/m2, whereas 43 were healthy asymptomatic volunteers with a BMI of <30 kg/m2. Patients with a history of clinical heart disease and pulmonary disease, electrolyte abnormalities, recent hospitalizations, or abnormal screening ECG or taking medications known to alter the QRS interval were excluded. At least 250 beats were analyzed with a noise level of <0.50 microV. Criteria of a late potential include QRS duration >114 ms, high-frequency low amplitude >38 ms, and root-mean-square voltage <20 microV. Patients were divided into four subgroups based on BMI values. The prevalence of SAECG abnormalities in each BMI subgroup was studied. We utilized multiple logistic regression analysis to study the effect of obesity, hypertension, and diabetes mellitus on abnormal SAECG results.

RESULTS

Compared to age- and sex-matched healthy volunteers with BMI of <30 kg/m2, obese patients with BMI of >30 kg/m2 had significantly more abnormalities on SAECG (4.6% vs. 55%). In the obese group, the prevalence and number of abnormalities increased with increase in BMI (35% in the BMI 31 to 40 kg/m2 subgroup, 86% in the BMI 41 to 50 kg/m2 subgroup, and 100% in patients with BMI of >50 kg/m2). Multiple logistic regression analysis shows that BMI is an independent predictor variable of abnormal SAECG results in obese patients (n = 62) with BMI of >30 kg/m2 as well as in all study subjects (n = 105). BMI also predicts abnormality of each abnormal SAECG criterion in both obese and all subjects. Hypertension was found to influence the QRS duration alone in obese and all subjects.

DISCUSSION

Obesity is associated with increased occurrence of abnormal SAECG results. These abnormalities are found both in obese patients with and without hypertension and/or diabetes. Obesity is an independent predictor variable of abnormal SAECG results. A history of hypertension predicts abnormality of QRS duration only.

The redistributive effect of health care finance in twelve OECD countries

The OECD countries finance their health care through a mixture of taxes, social insurance contributions, private insurance premiums and out-of-pocket payments. The various payment sources have very different implications for both vertical and horizontal equity and on redistributive effect which is a function of both. This paper presents results on the income redistribution consequences of the health care financing mixes adopted in twelve OECD countries by decomposing the overall income redistributive effect into a progressivity, horizontal inequity and reranking component. The general finding of this study is that the vertical effect is much more important than horizontal inequity and reranking in determining the overall redistributive effect but that their relative importance varies by source of payment. Public finance sources tend to have small positive redistributive effects and less differential treatment while private financing sources generally have (larger) negative redistributive effects which are to a substantial degree caused by differential treatment.

Equity in the finance of health care: some further international comparisons

This paper presents further international comparisons of progressivity of health care financing systems. The paper builds on the work of Wagstaff et al. [Wagstaff, A., van Doorslaer E., et al., 1992. Equity in the finance of health care: some international comparisons, Journal of Health Economics 11, pp. 361-387] but extends it in a number of directions: we modify the methodology used there and achieve a higher degree of cross-country comparability in variable definitions; we update and extend the cross-section of countries; and we present evidence on trends in financing mixes and progressivity.

Circumferential fingernail

We describe a Brazilian girl with a congenital circumferential nail on her left ring finger associated with other bony and soft tissue abnormalities of the affected limb. The tubular nail plate resembling a punch biopsy has been described as a circumferential nail, an extremely rare congenital malformation that can be associated with other congenital anomalies. In our review of the literature, there have only been two previous reports of this unusual condition affecting the fingernails.

Frozen shoulder--an algoneurodystrophic process?

The frozen shoulder syndrome and the Sudeck syndrome are clinically in many aspects similar. Radioisotope bone scan shows an increased uptake in the affected areas in both diseases, while standard radiographs show a progressive demineralization. With measurement of bone-mineral density by quantitative digital radiography these local decalcification processes were diagnosed in an early stage of the frozen shoulder syndrome: of 12 patients with primary frozen shoulder 10 had a bone-mineral density decrease of more than 21% in the humeral head of the affected shoulder compared to the unaffected side. In the control groups (n = 32) the difference between affected and unaffected side (left and right humerus of the healthy probands) was in only one case each above 21%. There are several indications in the literature assuming the frozen shoulder to be an algoneurodystrophic process. Our observation supports this hypothesis, and may possibly lead to earlier diagnosis and improved therapeutic management.

FMEV vectors: both retroviral long terminal repeat and leader are important for high expression in transduced hematopoietic cells

FMEV retroviral vectors combine the long terminal repeat of Friend mink cell focus-forming viruses with the 5' untranslated leader region of the murine embryonic stem cells virus. These modules were connected to achieve high transgene expression in hematopoietic progenitor and stem cells. Here, we report the cloning of safety-improved and versatile FMEV vectors allowing module-wise exchange of crucial elements for comparative studies. By transfer and expression of four different marker genes (neomycin phosphotransferase, lacZ, enhanced green fluorescent protein and truncated low affinity nerve growth factor receptor), we formally demonstrate that both the long terminal repeat and the leader contribute to the high expression of FMEV in transduced hematopoietic cells. Most prominent are the data recorded in the absence of selection in myelo-erythroid progenitor cells. Here, FMEV vectors mediate up to two orders of magnitude increased transgene expression levels when compared with vectors based on the Moloney murine leukemia virus.

Effect of NMDA lesion of the medial preoptic neurons on sleep and other functions

This study was undertaken to determine the effects of the destruction of the medial preoptic area (mPOA) neurons by N-methyl D-aspartic acid (NMDA), on sleep-wakefulness (S-W), locomotor activity, body weight, rectal temperature, and food and water intake in rats. The NMDA lesion of the mPOA produced long-lasting insomnia with marked reduction in the deeper stages of sleep, including paradoxical sleep. The reduction in the duration of sleep episodes in the lesioned rats indicated their inability to maintain sleep. The insomnia resulting from a decreased sleep pressure did not alter the sleep-initiating ability. Though the day-night distribution of sleep remained largely unaffected, there was an increase in locomotor activity during the light period. There was no increase in food intake to compensate for the high energy expenditure resulting not only from hyperactivity but also from hyperthermia in the mPOA-lesioned rats. Thus, body weights of the rats were reduced even without any change in food and water intake. However, the changes in body temperature and locomotor activity after the mPOA neuronal loss may not have exerted a major influence on S-W, as the alterations in all these parameters had different time courses.

Recovery of sleep after fetal preoptic transplantation in medial preoptic area-lesioned rats

Changes in sleep after fetal preoptic (POA) tissue transplantation were studied in rats which had been made insomniac by a medial preoptic area (mPOA) lesion. Two days after the N-methyl D-aspartic acid (NMDA) lesion of the mPOA, fetal POA tissues (obtained from 14- to 17-day-old fetuses) were transplanted into the lesioned mPOA. Insomnia was less marked in these animals, as compared to nontransplanted lesioned rats, even on the 4th day after transplantation. The quantum of sleep nearly attained the prelesion level by the 20th day. Body weight also showed recovery after transplantation. Rectal temperature, which was increased by the lesion of the mPOA, remained unaltered even after the transplantation. These results suggest that the recovery of sleep and rectal temperature may follow different time courses. Surviving transplanted neurons were seen at the site of lesion on postmortem examination. Humoral interaction between the host and the transplant may be responsible for the early recovery of sleep, though the establishment of neural connections between the host and transplant might have contributed to the later recovery. This is the first study to show the recovery of sleep function in insomniac animals after fetal preoptic tissue transplantation. However, the specificity of the POA fetal tissue, in comparison with other neural tissues to promote sleep recovery, remains to be established.

Symptom relief with amitriptyline in the irritable bowel syndrome

Anti-depressants have been reported to be useful in the management of the Irritable Bowel syndrome. We studied the efficacy of amitriptyline for 12 weeks in a randomized double-blind placebo-controlled trial. Forty patients who met predefined criteria entered the trial. They received 25 mg amitriptyline for the first week, 50 mg for the second week and 75 mg nightly thereafter until the end of the 12th week. The drug and placebo groups were comparable in all major pretreatment variables. Amitriptyline was found to be significantly more effective than placebo in producing global improvement, increasing feelings of well-being, reducing abdominal pain and increasing satisfaction with bowel movements. Younger age and increasing extroversion predicted a better response to amitriptyline. Severity of depressive and anxiety symptoms and other personality variables did not influence outcome.

Hepatitis A virus: declining seroprevalence in children and adolescents in Southeast Asia

The prevalence of hepatitis A virus (HAV) in a country largely reflects its standards of hygiene and socioeconomic conditions. Countries which undergo socioeconomic development show major change in HAV prevalence from high to low endemicity, and this is largely reflected in patterns of age-related seroprevalence. This paper presents age-related HAV seroprevalence patterns of SE Asian countries, and highlights how these patterns have changed over recent decades. Singapore, Thailand and Malaysia have experienced a decline in childhood and adolescent HAV seroprevalence, typical of countries which undergo socioeconomic development. By contrast, India has remained a country of high endemicity, with almost universal seroconversion in childhood. The Philippines and Vietnam show age-related seroprevalence patterns typical of high to moderate endemicity, while Indonesia shows significant regional variation in HAV seroprevalence. Populations within countries which exhibit major improvements in endemicity and age related HAV seroprevalence patterns are at risk of HAV epidemics, and a paradoxical increase in incidence tends to occur as seroconversion shifts from children to adults. The residents of these countries, a significant number of whom are at-risk, would benefit from a program of vaccination, as would non-infected individuals visiting high-risk areas.

Appendicitis among African patients at King Edward VIII Hospital, Durban, South Africa: a review

This retrospective study of 645 black patients, carried out over a five year period, showed that appendicitis is twice as common in males as in females and that it occurs predominantly in young people (median age 20 years). The classical presentation of periumbilical pain (16%) was outnumbered by right iliac fossa pain (36%) and non-specific pain (27%). The majority perforated (43%) and appendiceal inflammation was second commonest (37%). The negative appendicectomy rate was 8.8% and there was a diagnostic error of 14%. Mortality was two per cent mainly from patients complicated by peritonitis. Hospital stay was 7 +/- 7 days, with the longest stay following peritonitis. A diagnosis of appendicitis should always be entertained in an African patient presenting with an acute abdomen and, where the diagnosis is in doubt, a laparotomy should be performed.

Dominant selection of hematopoietic progenitor cells with retroviral MDR1 co-expression vectors

When transferring the human multidrug resistance 1 (MDR1) cDNA, FMEV retroviral vectors mediate high-dose multidrug resistance and, thus, background-free selection in primary human hematopoietic progenitor cells. Here, we analyzed strategies for co-expression of a second gene from an FMEV:MDR1 vector. When linking the cDNAs with the internal ribosomal entry site (IRES) of poliovirus or retroviral splice signals, almost all multidrug-resistant hematopoietic colonies simultaneously coexpressed the 3' positioned second gene, neomycin-phosphotransferase (neoR). The IRES strategy allowed functional co-transfer of a 4.2-kb lacZ-neoR fusion gene, resulting in a total proviral genome size of 11 kb, corresponding to the packaging limit of retroviral vectors. Preselection based on multidrug resistance elevated the expression of the second gene in IRES constructs, but not in splice vectors. Moreover, three intriguing observations were made. First, up to 30% of cells preselected for functional transfer of the 3' positioned cDNA (neoR) showed infunctional MDR1; this occurred irrespective of the linking principle and was associated with instability of the MDR1 transcription unit. Second, the levels of multidrug resistance achieved with the co-expression vectors were moderately lower (15-30% reduced) than those mediated by the monocistronic counterpart. Third, transduction with FMEV:MDR1 co-expression vectors still resulted in high-dose cancer drug resistance and background-free selection of hematopoietic progenitor cells (including primary human CD34+ colony-forming units). Thus, for the first time, we describe MDR1 co-expression vectors that maintain their desired function in early and primary human hematopoietic cells. However, careful interpretation of the data reveals that further vector improvements are required to obtain clinically useful MDR1 co-expression vectors.

Manual ventilation with a few large breaths at birth compromises the therapeutic effect of subsequent surfactant replacement in immature lambs

The reason why some infants with respiratory distress syndrome fail to respond to surfactant, or respond only transiently, is incompletely understood. We hypothesized that resuscitation with large breaths at birth might damage the lungs and blunt the effect of surfactant. Five pairs of lamb siblings were delivered by cesarean section at 127-128 d of gestation. One lamb in each pair was randomly selected to receive six manual inflations of 35-40 mL/kg ("bagging") before the start of mechanical ventilation, a volume roughly corresponding to the inspiratory capacity of lamb lungs after prophylactic surfactant supplementation. Both siblings were given rescue porcine surfactant, 200 mg/kg, at 30 min of age. Blood gases and deflation pressure-volume (P-V) curves of the respiratory system were recorded until the lambs were killed at 4 h. The P-V curves became steeper after surfactant in the control group, but no such effect was seen in those subjected to bagging. At 4 h, inspiratory capacity and maximal deflation compliance were almost three times higher (p < 0.01) in the controls than in the bagged lambs. The latter were also more difficult to ventilate and tended to have less well expanded alveoli and more widespread lung injury in histologic sections. We conclude that a few inflations with volumes that are probably harmless in other circumstances might, when forced into the surfactant-deficient lung immediately at birth, compromise the effect of subsequent surfactant rescue treatment. Our findings challenge current neonatal resuscitation practice of rapidly establishing a normal lung volume by vigorous manual ventilation.

Role of medial preoptic area beta adrenoceptors in the regulation of sleep-wakefulness

The role of the medial preoptic area (mPOA) beta adrenergic receptors in the regulation of sleep-wakefulness (S-W) was investigated in this study. S-W was assessed on the basis of polygraphic recording of EEG, EMG and EOG in free moving rats. Intracerebral microinjection of beta agonist, isoproterenol, into the mPOA produced arousal. The study was also conducted on another set of rats in which noradrenergic (NE) innervation to the mPOA was destroyed by injecting 6-hydroxydopamine into the ventral noradrenergic bundle, in the brain stem. Local application of isoproterenol, into the mPOA, in these animals, did not produce any significant change in S-W. Thus, the increase in awake period obtained on isoproterenol administration was the result of its action on the presynaptic NE terminals. Possible involvement of other responses in the isoproterenol induced increase in wakefulness, is discussed.

Pulmonary clearance of 99mTc-DTPA in experimental surfactant dysfunction treated with surfactant instillation

BACKGROUND

Breakdown of the alveolo-capillary barrier is a characteristic feature of respiratory distress syndrome. Restoration of alveolo-capillary barrier function may be an important aspect of surfactant replacement therapy. We examined the effect of surfactant instillation on alveolo-capillary barrier function in an experimental model of surfactant dysfunction by measuring pulmonary clearance of 99mTc-DTPA.

METHODS

Nineteen rabbits were tracheotomized and mechanically ventilated. Surfactant dysfunction was induced by administration of a synthetic detergent in aerosol form. Detergent was given to 13 rabbits; seven rabbits were then treated with instillation of natural surfactant, whereas six rabbits received saline. Six rabbits were used as untreated controls. An aerosol of 99mTc-DTPA was administered to all animals and the pulmonary clearance was measured with a gamma camera.

RESULTS

99mTc-DTPA cleared from the lungs with a half-life of 71 +/- 22 min in the control animals, 21.4 +/- 7.4 min in the surfactant-treated animals and 5.8 +/- 1.5 min in the saline-treated animals. The difference in half-life between groups was highly significant (P < 0.001). There was no change in arterial oxygenation or compliance in controls or in animals treated with saline. In animals treated with surfactant, a small transient reduction in arterial oxygen tension and a more long-standing reduction in compliance were observed.

CONCLUSION

Surfactant treatment thus significantly attenuated the effect of detergent treatment but did not restore alveolo-capillary transfer of 99mTc-DTPA to normal.

Surfactant dysfunction makes lungs vulnerable to repetitive collapse and reexpansion

Reexpansion of collapsed lung creates intrapulmonary shear forces. In an earlier study we showed that application of a negative end-expiratory airway pressure (NEEP) to normal rabbit lungs in vivo produced tidal collapse and reexpansion with transient changes in compliance and gas exchange but no histologic damage. In the present study we examined NEEP in a model of surfactant perturbation produced by an inhaled aerosol of 2% and 5% dioctyl sodium sulfosuccinate (DOSS). DOSS increased alveolocapillary permeability without affecting compliance or oxygenation. Repeated collapse and reexpansion (RECOREX), caused by NEEP for 3 h was compared with ventilation with positive-end expiratory pressure (PEEP). Groups ventilated with PEEP maintained normal lung mechanics and morphology even if pretreated with DOSS. NEEP disturbed lung mechanics and gas exchange with persistent dose-related histologic damage in animals pretreated with DOSS. Lungs subjected to NEEP without DOSS had normal morphology. We conclude that perturbation of the surfactant system makes lungs vulnerable to injury by RECOREX. The combination of DOSS and NEEP might lead to leakage of plasma proteins into alveoli, causing inactivation of surfactants and increased shear forces with resulting lung damage. Similar mechanisms may accelerate lung damage in the respiratory distress syndrome.

[Income, health, and health services utilization in Germany 1992]

Data from the 1992 wave of the Socioeconomic Panel were used to analyse the relation between incomes, need for and utilisation of health care in East- and West Germany employing methods coming from the economic measurement of income distributions. "Self assessed health" and "restricted activities of daily living" were employed as need indicators. Utilisation was measured by the number of "visits to physicians" and "days in hospital". Data was available for 6435 individuals (west) and 3928 individuals (east). Income was defined as equivalent net household income with an equivalence scale derived from the german social assistance program. Compared to the concentration of income all variables in the scope of this study were only marginally concentrated (i.e. equally distributed). A slight concentration of need amongst the lower income was overcompensated by utilisation. Thus a very small impact of the German health care system favouring lower income individuals was measured. The study shows methodological problems when combining data from regions with strongly different income levels instead of analysing them separately. A combined analysis tends to underestimate concentration.