Current cost of medical negligence in NHS hospitals: analysis of claims database

OBJECTIVES

To identify trends in the incidence and cost of clinical negligence claims. To determine the current annual cost to the NHS as a whole in terms of cash paid out to patients and their solicitors and the defence costs incurred.

DESIGN

Analysis of records on database.

SETTING

A well defined group of hospitals within one health authority which collected information on a consistent basis over many years.

MAIN OUTCOME MEASURES

Data on individual claims. Trends in incidence of claims and costs identified independently from organisational reforms and changes in accounting practices.

RESULTS

The rate of litigation increased from 0.46 to 0.81 closed claims per 1000 finished consultant episodes between 1990 and 1998. Overall expenditure on clinical negligence by the NHS in England in 1998 was estimated at 84 pound sterling million (95% confidence interval 48 pound sterling million to 130 pound sterling million).

CONCLUSIONS

After adjustment for hospital activity, the rate of closed claims increased during the 1990s by about 7% per annum, a substantial rate of growth but not the uncontrolled explosion sometimes alluded to in the wider media. More coordination and openness are needed in data collection.

Prognostic factors for medulloblastoma

PURPOSE

To evaluate prognostic factors for medulloblastoma.

METHODS AND MATERIALS

One hundred and seventy-three consecutive patients with medulloblastoma, treated at King Faisal Specialist Hospital (KFSH) from 1988-1997, were reviewed. Eighty-four percent were children less than 15 years old. From 1988-1994, treatment was at the discretion of the investigator. From 1994-1998, patients entered a single-arm best practice protocol in which, in staged patients, the surgical intent was total resection, standard radiation treatment was defined, and adjuvant chemotherapy was given to a "high-risk" subset.

RESULTS

For 150 patients who completed surgical and radiation treatment, the 5-year survival rate was 58%, compared with 0% for 16 patients who were unable to start or complete radiation treatment. For staged patients, the 5-year survival was M0 + M1, 78% and M2 + M3, 21% (p < 0.0001). Other favorable significant prognostic factors were age >14 years and gross cystic/necrotic features in the primary tumor. The size of the primary tumor, the degree of hydrocephalus at diagnosis, the presence of residual tumor in the post-operative CT/MRI, and the functional status of the patient prior to radiation treatment were not significant factors.

CONCLUSIONS

Stage M0 + M1 was the most powerful favorable prognostic factor. In Saudi Arabia more patients present with advanced disseminated disease, 41% M2 + M3, than in the West, and this impacts adversely on overall survival. Total resection and standard radiation treatment were not sensitive prognostic factors in a treatment environment in which 78% of patients underwent at least 90% tumor resection and 60% received standard radiation treatment. In order to improve the proportion of patients able to complete radiation treatment, consideration should be given to limiting resection when the attainment of total resection is likely to be morbid, and to delaying rather than omitting radiation treatment in the patient severely compromised postoperatively.

Cost effectiveness of an intensive blood glucose control policy in patients with type 2 diabetes: economic analysis alongside randomised controlled trial (UKPDS 41). United Kingdom Prospective Diabetes Study Group

OBJECTIVE

To estimate the cost effectiveness of conventional versus intensive blood glucose control in patients with type 2 diabetes.

DESIGN

Incremental cost effectiveness analysis alongside randomised controlled trial.

SETTING

23 UK hospital clinic based study centres.

PARTICIPANTS

3867 patients with newly diagnosed type 2 diabetes (mean age 53 years).

INTERVENTIONS

Conventional (primarily diet) glucose control policy versus intensive control policy with a sulphonylurea or insulin.

MAIN OUTCOME MEASURES

Incremental cost per event-free year gained within the trial period.

RESULTS

Intensive glucose control increased trial treatment costs by pound 695 (95% confidence interval pound 555 to pound 836) per patient but reduced the cost of complications by pound 957 (pound 233 to pound 1681) compared with conventional management. If standard practice visit patterns were assumed rather than trial conditions, the incremental cost of intensive management was pound 478 (-pound 275 to pound 1232) per patient. The within trial event-free time gained in the intensive group was 0.60 (0.12 to 1.10) years and the lifetime gain 1.14 (0.69 to 1.61) years. The incremental cost per event-free year gained was pound 1166 (costs and effects discounted at 6% a year) and pound 563 (costs discounted at 6% a year and effects not discounted).

CONCLUSIONS

Intensive blood glucose control in patients with type 2 diabetes significantly increased treatment costs but substantially reduced the cost of complications and increased the time free of complications.

United Kingdom national confidential enquiry into perioperative deaths

The enquiry (NCEPOD) was established to examine simultaneously the anaesthetic and surgical circumstances surrounding the death of a patient undergoing surgery, it reviewed clinical practice and identified remedial factors in the practice of anaesthesia and surgery in order to improve the quality of care. Data were reported on every death occurred within 30 days of a procedure performed by a surgeon or gynaecologist under general or local anaesthesia, excepting obstetric deaths, and were collected int he sample of questionnaires to surgeons and anaesthesists involved. In high risk patient the optimisation of cardiovascular system with fluids, inotropic agents, beta-blockers and invasive monitoring may improve mortality (a speculative calculation reported 1,700 out 19,000 lives saved in 1994/1995 in UK). The majority of deaths occurred in emergency operations, urgent operations delayed for no operating theatre free during the day, training personnel which performed emergency operations during the night and/or postoperative care provided by non specialized clinicians, hospital not equipped with high dependency units (HDU), surgery undertaken although the predictable infaust outcome, they were all problems outlooked by the investigation. In conclusion improvements are necessary in hospital facilities and working pattern of surgeons and anaesthesists.

Centre-specific or average unit costs in multi-centre studies? Some theory and simulation

Costing issues are increasingly being addressed in multi-centre studies. In this paper, two methods for collecting costing information are compared within a simulated clinical trial setting. One method estimates average treatment costs by applying unit costs averaged across treatment centres to centre-specific volumes of resource use. The second uses centre-specific information for both the unit costs and the resource volumes, and then averages across centres. Using a pre-specified production relation between the different volumes of resource use, and simulating changes in unit costs, it is shown that these two methods result in statistically different estimates of average treatment costs. This finding holds, regardless of the degree of substitutability between the resource volumes, except when considerable uncertainty surrounds treatment centre responses to relative changes in unit costs. The findings suggest that a more cautious approach should be adopted in the collection, calculation and interpretation of treatment costs in multi-centre studies.

Analysis of the cellular functions of PTEN using catalytic domain and C-terminal mutations: differential effects of C-terminal deletion on signalling pathways downstream of phosphoinositide 3-kinase

The tumour suppressor protein, PTEN (phosphatase and tensin homolog deleted on chromosome 10), is a phosphatase that can dephosphorylate tyrosine-containing peptides, Shc, focal adhesion kinase and phosphoinositide substrates. In cellular assays, PTEN has been shown to antagonize the PI-3K-dependent activation of protein kinase B (PKB) and to inhibit cell spreading and motility. It is currently unclear, however, whether PTEN accomplishes these effects through its lipid- or protein-phosphatase activity, although strong evidence has demonstrated the importance of the latter for tumour suppression by PTEN. By using a PTEN G129E (Gly(129)-->Glu) mutant that has lost its lipid phosphatase activity, while retaining protein phosphatase activity, we demonstrated a requirement for the lipid phosphatase activity of PTEN in the regulation of PKB activity, cell viability and membrane ruffling. We also made a small C-terminal deletion of PTEN, removing a putative PDZ (PSD95, Dlg and ZO1)-binding motif, with no detectable effect on the phosphatase activity of the protein expressed in HEK293 cells (human embryonic kidney 293 cells) assayed in vitro. Surprisingly, expression of this mutant revealed differential requirements for the C-terminus in the different functional assays. Wild-type and C-terminally deleted PTEN appeared to be equally active in down-regulating PKB activity, but this mutant enzyme had no effect on platelet-derived growth factor (PDGF)-induced membrane ruffling and was only partially active in a cell viability assay. These results stress the importance of the lipid phosphatase activity of PTEN in the regulation of several signalling pathways. They also identify a mutation, similar to mutations that occur in some human tumours, which removes the effect of PTEN on membrane ruffling but not that on PKB.

Psychotic symptoms, aggression and restlessness in dementia

The current article reviews the literature pertaining to psychosis, aggression and restlessness in dementia sufferers examining frequency, course and associations as well as treatment considerations. All of these problems are highly prevalent, with a high impact upon dementia sufferers and their carers. Although there has been an expansion in this literature over the last few years there are still very few studies describing the natural course of behavioural and psychological symptoms in dementia (BPSD) and a paucity of data relating to non-Alzheimer dementias. Several large treatment studies have recently been completed, but there are still very few double blind controlled trials focusing upon BPSD in particular respect to non-pharmacological interventions.

Extramedullary myeloid tumors in children: the limited value of local treatment

PURPOSE

To determine the incidence of extramedullary tumors (EMT) in Saudi Arabian children with acute myeloid leukemia, the factors associated with these tumors and the impact of local treatment on local tumor control, complete remission and survival rates.

PATIENTS AND METHODS

One hundred children, median age 6 years, who received their primary treatment for acute myeloid leukemia at King Faisal Specialist Hospital and Research Center, from 1983 to 1997 were studied. EMT at diagnosis occurred in 18 (18%) patients at 25 sites. Meningeal leukemia, hepatosplenomegaly, lymph node enlargement, gingival hypertrophy, and cutaneous infiltration were not included in the definition of EMT. With these exclusions, children with EMT were younger than those without EMT (median age, 3.5 v. 7.5 years) and were more likely to have meningeal leukemia at diagnosis (33% v. 10%). The t(8;21) translocation was associated with a 47% EMT incidence compared with 23% without the translocation. Local radiation treatment was given to 16 of 25 (64%) EMT sites.

RESULTS

The overall 5-year survival rate for all patients was 28%, and this was not significantly influenced by the drug regimen used, meningeal leukemia at diagnosis, the presence of the (8;21) translocation, M4 and M5 morphology combined, or EMT at diagnosis. Significant differences were observed in the 5-year survival rates for patients who underwent allogeneic bone marrow transplantation (52%; N = 37) and those who attained complete remission (CR) but did not undergo transplantation (21%; N = 44) and those who did not achieve complete remission with initial therapy (5%; N = 19). Systemic and local EMT CR was achieved in 17 of 18 patients with EMT, including 12 patients who underwent radiation treatment and 5 of 6 of those who did not. Isolated relapse was not seen at an EMT site and was not noted at any later stage of the disease.

CONCLUSIONS

Permanent local control at sites of EMT was achieved in all patients who attained a bone marrow CR, whether or not the site was irradiated. Local radiation treatment of an EMT site did not appear to contribute to overall CR and survival rates. The use of radiation treatment should be conservative and limited to patients in whom there is a real and immediate threat to vision or renal function or when the spinal cord is compromised.

HEALTH ECONOMICS AND ORTHOPAEDICS

It is becoming widely accepted that research which considers only the outcome and not the costs associated with new technologies in health care, is of limited value in making decisions about the use of scarce resources. Economic evaluation is becoming a standard feature of clinical research but many published economic evaluations fall short of best practice in their methodology. We have described the essential features of economic evaluation, using published studies in orthopaedics, in order to try to improve the ability of orthopaedic surgeons to read, understand and appraise such studies critically, and to encourage them to consider including economic evaluation in future investigations.

Case management for people with severe mental disorders

BACKGROUND

Since the 1960s, in many parts of the world, large psychiatric were closed down and people were treated in outpatient clinics, day centres or community mental health centres. Rising readmission rates suggested that this type of community care may be less effective than anticipated. In the 1970s case management arose as a means of co-ordinating the care of severely mentally ill people in the community.

OBJECTIVES

To determine the effects of case management as an approach to caring for severely mentally ill people in the community. Case management was compared against standard care on four main indices: (i) numbers remaining in contact with the psychiatric services; (ii) extent of psychiatric hospital admissions; (iii) clinical and social outcome; and (iv) costs.

SEARCH STRATEGY

Electronic searches of CINAHL (1997), the Cochrane Schizophrenia Group's Register of trials (1997), EMBASE (1980-1995), MEDLINE (1966-1995), PsycLIT (1974-1995) and SCISEARCH (1997) were undertaken. References of all identified studies were searched for further trial citations.

SELECTION CRITERIA

The inclusion criteria were that studies should be randomised controlled trials that (i) had compared case management to standard community care; and (ii) had involved people with severe mental disorder mainly between the ages of 18-65. Studies of case management were defined as those in which the investigators described the intervention as 'case' or 'care' management rather than 'Assertive Community Treatment' or 'ACT'.

DATA COLLECTION AND ANALYSIS

A study was carried out to test the reliability of the inclusion criteria. Categorical data were extracted twice and then cross-checked, any disagreements being resolved by discussion. Odds ratios and the number needed to treat were estimated. Continuous data collected by a measuring instrument was only included if the instrument (i) had been described in a peer-reviewed journal; (ii) was a self-report or had been completed by an independent rater; and (iii) provided a summary score for a broad area of functioning. Normally distributed continuous data were included if means and standard deviations were available. Non-normal data were included if analysed either after transformation or using non-parametric methods. Tests for heterogeneity were conducted.

MAIN RESULTS

Case management increased the numbers remaining in contact with services (for case management odds ratio = 0.70; 99%CI 0.50-0. 98; n=1210). Case management approximately doubled the numbers admitted to psychiatric hospital (OR 1.84; 99% CI 1.33-2.57; n=1300). Except for a positive finding on compliance, from one study, case management showed no significant advantages over standard care on any psychiatric or social variable. Cost data did not favour case management but insufficient information was available to permit definitive conclusions.

REVIEWER'S CONCLUSIONS

Case management ensures that more people remain in contact with psychiatric services (one extra person remains in contact for every 15 people who receive case management), but it also increases hospital admission rates. Present evidence suggests that case management also increases duration of hospital admissions, but this is not certain. Whilst there is some evidence that case management improves compliance, it does not produce clinically significant improvement in mental state, social functioning, or quality of life. There is no evidence that case management improves outcome on any other clinical or social variables. Present evidence suggests that case management increases health care costs, perhaps substantially, although this is not certain. In summary, therefore, case management is an intervention of questionable value, to the extent that it is doubtful whether it should be offered by community psychiatric services. It is hard to see how policy makers who subscribe to an evidence-based approach can justify retaining case management as 'the cornerstone' of community mental hea

Health economics and orthopaedics

It is becoming widely accepted that research which considers only the outcome and not the costs associated with new technologies in health care, is of limited value in making decisions about the use of scarce resources. Economic evaluation is becoming a standard feature of clinical research but many published economic evaluations fall short of best practice in their methodology. We have described the essential features of economic evaluation, using published studies in orthopaedics, in order to try to improve the ability of orthopaedic surgeons to read, understand and appraise such studies critically, and to encourage them to consider including economic evaluation in future investigations.

The pleckstrin homology domains of protein kinase B and GRP1 (general receptor for phosphoinositides-1) are sensitive and selective probes for the cellular detection of phosphatidylinositol 3,4-bisphosphate and/or phosphatidylinositol 3,4,5-trisphosphate in vivo

We have tested the binding specificities of the pleckstrin homology (PH) domains of protein kinase B (PKB) and GRP1 (general receptor for phosphoinositides-1), expressed as green fluorescent protein (GFP) fusion proteins [PH(PKB)GFP and PH(GRP1)GFP respectively] in HEK 293 cells and Swiss 3T3 cells, using confocal microscopy. Stimulation of HEK 293 cells with insulin caused a small, but sustained, increase in PtdIns(3,4,5)P(3) levels, detected using a radioligand displacement assay, which was mirrored by the translocation of PH(PKB)GFP and PH(GRP1)GFP from the cytosol to the plasma membrane of live, transfected cells. Similar results were obtained using Swiss 3T3 cells stimulated with platelet-derived growth factor (PDGF) and expressing either PH(PKB)GFP or PH(GRP1)GFP. Biochemical analyses confirmed the accumulation of both PtdIns(3,4,5)P(3) and PtdIns(3,4)P(2) in response to PDGF, but only the latter was present at increased levels in Swiss 3T3 cells 30 min after an oxidative stress (1 mM H(2)O(2)). Concomitantly, only PH(PKB)GFP, and not PH(GRP1)GFP, was localized at plasma membranes after 30 min of treatment with H(2)O(2). The fusion proteins appear accurately to report the spatial and temporal distribution of PtdIns(3,4,5)P(3) and PtdIns(3,4)P(2) in intact cells. These results establish the lipid selectivity of these PH domains in vivo, and further emphasize the overlapping, but distinct, second messenger roles of PtdIns(3,4,5)P(3) and PtdIns(3,4)P(2).

Distinct phosphatidylinositol 3-kinase lipid products accumulate upon oxidative and osmotic stress and lead to different cellular responses

Signaling by phosphatidylinositol (PI) 3-kinases is mediated by 3-phosphoinositides, which bind to Pleckstrin homology (PH) domains that are present in a wide spectrum of proteins. PH domains can be classified into three groups based on their different lipid binding specificities. Distinct 3-phosphoinositides can accumulate upon PI 3-kinase activation in cells in response to different stimuli and mediate specific cellular responses. In Swiss 3T3 mouse fibroblasts, oxidative stress induced by 1 mM H(2)O(2) caused almost exclusive accumulation of phosphatidylinositol 3,4-bisphosphate (PtdIns(3, 4)P(2)), whereas osmotic stress increased both phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P(3)) and PtdIns(3,4)P(2) levels. The increase in PtdIns(3,4)P(2) levels, caused by oxidative stress, correlated with the activation of protein kinase B, which has a promiscuous PH domain that binds both PtdIns(3,4,5)P(3) and PtdIns(3, 4)P(2). p70 S6 kinase, another signaling component downstream of PI 3-kinase, however, was not activated by this oxidative stress-induced increase in PtdIns(3,4)P(2) levels. Increased PtdIns(3,4,5)P(3) and PtdIns(3,4)P(2) levels in response to osmotic stress did not correlate with protein kinase B activation, because of concomitant activation of an inhibitory pathway, but p70 S6 kinase was activated by osmotic stress. These results demonstrate that PtdIns(3,4)P(2) can accumulate independently of PtdIns(3,4, 5)P(3) and exerts a pattern of cellular responses that is distinct from that induced by accumulation of PtdIns(3,4,5)P(3).

Effects of recombinant ovine interferon tau, placental lactogen, and growth hormone on the ovine uterus

Studies were conducted to determine effects of intrauterine administration of recombinant ovine interferon tau (IFNtau), placental lactogen (PL), and growth hormone (GH) on endometrial function. In the first study, administration of IFNtau to cyclic ewes for one period (Days 11-15) resulted in an interestrous interval (IEI) of approximately 30 days, whereas administration for two periods (Days 11-15 and Days 21-25) extended the IEI to greater than 50 days. Administration of IFNtau from Days 11 to 15 and of PL or GH from Days 21 to 25 failed to extend the IEI more than for IFNtau alone. In the second study, effects of IFNtau, PL, and GH on endometrial differentiation and function were determined in ovariectomized ewes receiving ovarian steroid replacement therapy. Endometrial expression of mRNAs for estrogen receptor (ER), progesterone receptor (PR), and oxytocin receptor (OTR) were not affected by PL or GH treatment; however, uterine milk protein mRNA levels and stratum spongiosum gland density were increased by both PL and GH treatments. Collectively, results indicated that 1) PL and GH do not regulate endometrial PR, ER, and OTR expression or affect corpus luteum life span; 2) down-regulation of epithelial PR expression is requisite for progesterone induction of secretory gene expression in uterine glandular epithelium; 3) effects of PL and GH on endometrial function require IFNtau; and 4) PL and GH regulate endometrial gland proliferation and perhaps differentiated function.

Reproductive issues in HIV-seropositive women: a survey regarding counseling, contraception, safer sex, and pregnancy choices

Sixty-nine HIV-seropositive women were surveyed with regard to the reproductive counseling they had received, contraception, safer sex practices, pregnancy histories, and pregnancy plans. Of the women surveyed, 84% and 90%, respectively, felt that they had access to the birth control and safer sex methods of their choice. Less than half felt that their physician had adequately counseled them about birth control. Women primarily cited social workers (46.4%) or nurses (34.8%) as the counseling source for birth control and safer sex. When informed about the reduced risk of vertical transmission with zidovudine (AZT), 33 women indicated that information regarding AZT would affect their future pregnancy decisions. Health care professionals need to be aware of this and counsel patients accordingly.

Adjuvant chemotherapy with vincristine, doxorubicin, and cyclophosphamide in the treatment of postenucleation high risk retinoblastoma

PURPOSE

To study risk factors and outcome of children with high risk retinoblastoma who receive postenucleation vincristine, doxorubicin, and cyclophosphamide.

PATIENTS AND METHODS

Charts of all patients who received adjuvant chemotherapy for retinoblastoma were reviewed. Thirty-six patients were identified who received chemotherapy for high risk histopathologic features. Histopathology slides of these 36 patients were retrieved and reviewed, and the disease was staged according to the modified St. Jude staging system. The disease was unilateral in 23 patients (64%). There were 9 patients with stage I disease, 18 with stage II, and 9 with stage III. Twenty-four patients (67%) completed 12 of the 12 scheduled chemotherapy cycles, and 11 patients (30%) received 4 to 11 cycles because of relapse, disease progression, or family reasons. A life-threatening complication developed in one patient after the first cycle, and this patient received no further chemotherapy.

RESULTS

Five (3 with unilateral and 2 with bilateral disease) of the 36 patients developed distant metastasis and subsequently died. All had massive tumors; three had choroidal and up to surgical margin optic nerve invasion, and two had tumor extending posterior to lamina cribrosa. Six other patients had local relapse or progressive disease. All of these six patients had bilateral disease and failed in the intact eye during (three patients) or after (three patients) chemotherapy. Only two of the six patients were alive with no disease 50 and 102 months from diagnosis. With a median follow-up of 5.6 years, the 5-year and 10-year actuarial overall survival rates were 86% and 74%, respectively. The 5-year survival rates for patients with modified St. Jude stage I, II, and III disease were 100%, 91% (95% confidence interval, 57% to 100%), and 58% (95% confidence interval, 22% to 94%), respectively (P = 0.008). The survival rate was significantly different among patients with optic nerve involvement anterior to lamina cribrosa, posterior to lamina cribrosa, and surgical margin involvement (100%, 55%, and 41%, respectively; P = 0.003). Multivariate analysis showed that only the degree of optic nerve involvement (and therefore, modified St. Jude stage) was predictive of poor outcome.

CONCLUSION

Patients with retinoblastoma involving the optic nerve beyond the lamina cribrosa have low survival rate despite local therapy and adjuvant chemotherapy with vincristine, doxorubicin, and cyclophosphamide. Progression of disease in the intact eye of three patients receiving chemotherapy is of concern. Alternative chemotherapeutic agents should be considered for patients with such high risk features.

Estimating long-term cost savings from treatment of Alzheimer's disease. A modelling approach

OBJECTIVE

This paper puts forward a proposal for a modelling approach to the estimation of long term cost savings from the treatment of Alzheimer's disease (AD).

DESIGN

In the proposed modelling approach, disease progression is defined in terms of intervals in the Mini-Mental State Exam (MMSE) scale. Clinical trial data are then used to determine the time at which a particular patient moved into a more severe stage of the disease. By comparing these durations across treatment groups, survival analysis is used to measure the impact of treatment in delaying the onset of a more costly stage of the disease.

SETTING

Patients with varying severity of AD.

PATIENTS AND PARTICIPANTS

The model uses clinical trial data on 1333 patients recruited internationally in 2 studies from 67 centres.

INTERVENTIONS

The aim of these clinical studies was to evaluate the safety and efficacy of 2 non-overlapping dose ranges of rivastigmine relative to placebo over a 26-week treatment period in patients with probable AD.

MAIN OUTCOME MEASURES AND RESULTS

The results indicate that the average cost savings with high-dose rivastigmine at the end of the trial period are quite low (approximately 29 Pounds per patient; 1997 values), but by extrapolating to a projected lifetime of 3 years, they rise to approximately 1100 Pounds per patient. The largest long term cost savings from treatment are obtained from treating those in the mild category (i.e. MMSE > 20). However, if the time horizon over which savings are estimated is short (i.e. if life expectancy is below 2 years), more costs are saved by prioritising patients with moderate AD (i.e. MMSE between 20 and 11).

CONCLUSIONS

The model is a possible approach for estimating cost savings with treatment of AD, given the lack of long term data on resource use and drug efficacy. Caution should be used when extrapolating the results beyond the original study parameters.

Fibrinogen

Fibrinogen is a blood-borne glycoprotein comprised of three pairs of nonidentical polypeptide chains. Following vascular injury, fibrinogen is cleaved by thrombin to form fibrin which is the most abundant component of blood clots. As well as controlling blood loss at sites of tissue damage, other properties of fibrinogen have recently been discovered. For example, various cleavage products of fibrinogen and fibrin, released during coagulation and fibrinolysis, respectively, regulate cell adhesion and spreading, display vasoconstrictor and chemotactic activities, and are mitogens for several cell types including fibroblasts, endothelial and smooth muscle cells. Current research aims to define the bioactive fibrinogen molecule moieties and cellular receptors involved in these processes. Future studies may provide us with new opportunities to develop agents which are useful in promoting tissue repair or conversely in inhibiting fibrosis in inflammatory and fibroproliferative diseases where endothelial cell damage or chronic leakage of blood proteins is a feature.

A role for AMPA/kainate receptors in conditioned place preference induced by diazepam in the rat

There is increasing evidence for a role of glutamate receptors in the reinforcing properties of dependence producing drugs such as the psychostimulants and opiates. Activation of AMPA/kainate receptors are implicated in the acquisition of amphetamine-induced reinforcement but a role for this receptor in benzodiazepine-induced reinforcement has not been examined. In the present study the ability of the orally active AMPA/kainate antagonist GYKI 52466 was assessed for its ability to block the reinforcing properties of diazepam in a conditioned place preference paradigm. Diazepam (2.5 and 5.0 mg/kg, i.p.) produced a robust place preference and GYKI 52466 inhibited the acquisition of place preference conditioning-induced by diazepam. These results suggest that glutamatergic pathways are an important component of the circuitry involved in the acquisition of a benzodiazepine induced place preference.