Acute tonsillitis: an unusual presentation of Kawasaki syndrome: a case report and review of the literature

Kawasaki syndrome is an acute, self-limiting vasculitis that occurs mainly in children. The disorder is difficult to diagnose, a problem compounded by the lack of a specific diagnostic test. If the condition is unrecognised or treated sub-optimally, there is a 25% risk of developing serious cardiovascular complications. We report the case of an 8-year-old boy presenting with a history of acute tonsillitis and cervical lymphadenopathy in which the diagnosis of Kawasaki syndrome became apparent 4 days after admission. The case emphasises the importance of having a high index of suspicion for Kawasaki syndrome in children presenting with tonsillitis and cervical lymphadenopathy who do not respond to antibiotics or who have atypical features at the time of or after admission. A literature review of previous cases reveals a higher than usual age of presentation for the disease that could result in a greater percentage of cardiac complications.

Molecular pathogenesis of Wilson disease: haplotype analysis, detection of prevalent mutations and genotype-phenotype correlation in Indian patients

Wilson disease (WD) is an autosomal recessive disorder caused by defects in the copper-transporting P-type ATPase gene (ATP7B) resulting in the accumulation of copper in the liver and the brain. We identified prevalent mutations in the ATP7B of Indian WD patients and attempted to correlate those with the disease phenotype. Patients from 62 unrelated families and their first-degree relatives comprising 200 individuals were enrolled in this study. Three dinucleotide repeat markers flanking WD locus and a few intragenic SNPs were used to determine the genotypes and construct haplotypes of the patients. Seven recurring haplotypes accounting for 58% of the total mutant chromosomes were identified, and four underlying defects in the ATP7B representing 37% of WD chromosomes were detected. In addition, five other rare mutations were characterized. Thus a total of nine mutations including five novel changes were identified in the ATP7B of WD patients. Interestingly, homozygotes for different mutations that would be expected to produce similar defective proteins showed significant disparity in terms of organ involvement and severity of the disease. We also observed WD patients with neurological symptoms with little or no manifestation of hepatic pathogenesis. In one WD family, the proband and a sib had remarkably different phenotypes despite sharing the same pair of mutant chromosomes. These findings suggest a potential role for yet unidentified modifying loci for the observed phenotypic heterogeneity among the WD patients.

Curtailment of higher surgical training in the UK: likely effects in otology

Higher surgical training in the UK faces a cut of two years. We conducted a questionnaire survey to assess the operative experience of current higher surgical trainees in otological surgery and the likely effect of the proposed reduction from six to four years. 91 (65%) of the 142 higher surgical trainees responded with details of major otological procedures performed (independently or assisting) over one year. In the present six-year scheme a typical trainee performs 72 myringoplasties, 79 mastoidectomies, 7 skull base procedures and 28 other procedures. In the first four years, however, his or her experience is only 39 myringoplasties, 44 mastoidectomies, 4 skull base procedures and 7 others. The large shortfall in experience that might result from shortening of the training programme would need to be met by intensification of the training or institution of accredited otology fellowships. Very similar dilemmas are faced by other surgical specialties.

Risk of hypertension and reduced kidney function after acute gastroenteritis from bacteria-contaminated drinking water

BACKGROUND

The long-term health consequences of acute bacterial gastroenteritis remain uncertain. We studied the risk of hypertension and reduced kidney function after an outbreak of acute gastroenteritis due to contamination of a regional drinking water supply with Escherichia coli O157:H7 and Campylobacter species.

METHODS

A total of 1958 adults with no known history of hypertension or kidney disease before the outbreak participated in a long-term follow-up study. Of the participants, 675 had been asymptomatic during the outbreak, 909 had had moderate symptoms of acute self-limited gastroenteritis, and 374 had had severe symptoms that necessitated medical attention. The outcomes of interest were a diagnosis of hypertension or the presence of reduced kidney function and albuminuria during the follow-up period.

RESULTS

After a mean follow-up of 3.7 years after the outbreak, hypertension was diagnosed in 27.0% of participants who had been asymptomatic during the outbreak and in 32.3% and 35.9% of those who had had moderate and severe symptoms of acute gastroenteritis respectively (trend p = 0.009). Compared with the asymptomatic participants, those with moderate and severe symptoms of gastroenteritis had an adjusted relative risk of hypertension of 1.15 (95% confidence interval [CI] 0.97-1.35) and 1.28 (95% CI 1.04-1.56) respectively. A similar graded association was seen for reduced kidney function, defined as the presence of an estimated glomerular filtration rate below 60 mL/min per 1.73 m2 (trend p = 0.03). No association was observed between gastroenteritis and the subsequent risk of albuminuria.

INTERPRETATION

Acute bacterial gastroenteritis necessitating medical attention was associated with an increased risk of hypertension and reduced kidney function 4 years after infection. Maintaining safe drinking water remains essential to human health, as transient bacterial contaminations may have implications well beyond a period of acute self-limited illness.

Temperament in the rat: sex differences and hormonal influences on harm avoidance and novelty seeking

This study showed large and consistent individual differences in 64 rats (32 males) in the hole board and canopy test, which are considered to measure exploration and anxiety, respectively. Nonestrous females were more active than males and nose poked more in the hole board. In the canopy test, nonestrous females, compared with males, showed greater intraindividual variability in time spent outside the protective canopy. Estrous females spent significantly more time outside the canopy. Gonadectomy reduced nose poking in males and hole board locomotion in both sexes. Principal-components analysis disclosed 2 temperamental dimensions reflecting harm avoidance and novelty seeking. More males had high levels of psychometric harm avoidance, and fewer males than females had a low-harm-avoidance/high-novelty-seeking, sanguine profile.

Risk of stroke in women exposed to low-dose oral contraceptives: a critical evaluation of the evidence

BACKGROUND

Use of the oral contraceptive pill (OCP) has been reported to be associated with stroke. With current OCPs containing less than 50 micro g of ethinyl estradiol, and many earlier studies reporting the association between OCPs and stroke, subjected to biases, we determined whether such an association exists and, if so, the magnitude of the risk.

METHODS

Two independent searches were conducted to obtain relevant articles from MEDLINE, EMBASE, and Science Citation (1970 to June 2000). Eligible articles published in English describing OCP use and stroke outcomes were retrieved, and relevant data were abstracted. Pooling of results from these studies was performed using odds ratios (ORs) provided, and heterogeneity was calculated using chi(2) analysis.

RESULTS

From 779 potential articles, 36 eligible studies describing 20 distinct populations were retrieved (4 cohort and 16 case-control studies). The pooled OR from the cohort studies demonstrated no increased stroke risk with OCP use (0.95; 95% confidence interval [CI], 0.51-1.78; P =.01); the pooled OR from the case-control studies showed a significant association (2.13; 95% CI, 1.59-2.86; P<.001). The risk of stroke with OCP use, however, was significant only with thrombotic stroke (2.74; 95% CI, 2.24-3.35; P =.009) and not with hemorrhagic stroke or stroke death. There was statistically significant heterogeneity among these studies, and potential biases and confounders were not adequately addressed.

CONCLUSIONS

These results cast doubt on a true association between low-dose OCPs and stroke because of the low absolute magnitude of the ORs, the severe methodological limitations, and the ORs of less than 1.0 in the cohort studies. The association is tenuous at best and perhaps nonexistent.

Survival and differentiation of adult rat-derived neural progenitor cells transplanted to the striatum of hemiparkinsonian rats

We investigated the survival, distribution and differentiation capabilities of adult rat hippocampus-derived progenitor cells (AHPs) by grafting them into either the intact or dopamine (DA)-denervated adult rat striatum (ST). Furthermore, we tested the effects of the in vivo administration of retinoic acid (RA) on the differentiation of the grafted cells. AHPs, prelabeled in vitro with bromodeoxyuridine (BrdU) and primed with RA, were transplanted bilaterally into the ST of hemiparkinsonian rats. Twenty animals were divided in four groups: three groups received i.p. injections of RA (1.5 mg/kg/day) for 1, 2 or 4 weeks and one group received vehicle injections for 4 weeks. Approximately 60% of the implanted BrdU-immunoreactive (BrdU+) cells were present in either intact or lesioned ST after 5 weeks of transplantation, with a striking widespread radial distribution from the implantation site. The cells became morphologically integrated with the surrounding host tissue, with no evidence of tumor formation. Approximately 18% of the BrdU+ cells were immunoreactive for the glial precursor marker NG2 and occasionally BrdU+ cells co-expressed the neuronal marker TuJ1. This differentiation pattern was similar in the intact and DA-denervated ST. Although further research is needed to find more adequate methods to drive the differentiation of these cells toward the desired phenotypes, the survival, differentiation potential and widespread distribution throughout the ST observed in this study suggest that AHPs may be useful in treatment of degenerative disorders affecting the nervous system.

Managing antituberculosis drug therapy by therapeutic drug monitoring of rifampicin and isoniazid

BACKGROUND

Current therapeutic regimens with rifampicin and isoniazid have proven successful in treating tuberculosis, however, toxicity, therapeutic failure, relapse and multiple drug resistance are serious concerns. Optimizing drug dose using therapeutic drug monitoring (TDM) may be a better approach than administering therapy as a standard dose.

AIMS

To establish and evaluate a TDM service to optimize rifampicin and isoniazid therapy.

METHODS

A TDM service for rifampicin and isoniazid was established in November 1998. Drug concentration data were collected, with relevant information to interpret the results. The reason for the request, information on concomitant drug administration and a questionnaire to assess clinical response to the drug results were also obtained.

RESULTS

Ninety patient episodes were accepted for study. The rifampicin plasma concentrations showed significant scatter, with 46% of the rifampicin concentrations below the normal range and 2% above the normal range. Similarly, 48% of isoniazid concentrations were below the lower target of the normal range and 29% were above the upper normal limit. There was a greater proportion of isoniazid concentrations above the normal range in female patients.

CONCLUSION

Significant pharmacokinetic variability was observed for rifampicin and isoniazid in the patient population studied. Further, a substantial number of plasma concentrations fell outside the suggested normal range for both drugs. Isoniazid plasma concentrations were significantly higher in female patients compared with male patients. Despite these abnormal results, the dose of rifampicin and isoniazid was altered in only 17% of patients, however, many patients received follow-up education because of the drug result. The service was considered valuable by 83% of respondents to the questionnaire. While TDM of rifampicin and isoniazid is a valuable tool to optimize the dose of these drugs in some patients, there is an urgent need for concentration-effect studies and possibly education on the principles and practice of TDM for these drugs.

Spontaneous thoracic duct cyst

Spontaneous and asymptomatic supraclavicular thoracic duct cysts (lymphoceles ) are rare. Only five cases have been reported so far. They are more common after surgery or trauma and have been reported in the abdomen, mediastinum, pelvis and neck. They must be differentiated from other neck cysts as failure to recognise their attachment may result in the disastrous consequence of chylothorax. A high index of suspicion is necessary, and diagnosis usually can be established by fine-needle aspiration and suitable imaging. This case is reported along with a review of the literature and management options, including that of inadvertent damage to the thoracic duct.

Carbon monoxide poisoning and sensorineural hearing loss

Exposure to carbon monoxide is a well-recognized cause of morbidity and mortality. Both acute accidental poisoning and chronic exposure are associated with a range of adverse health effects. We report two cases of carbon monoxide poisoning with the associated phenomenon of sensorineural hearing loss. Although hearing loss as a result of acute carbon monoxide exposure has previously been described, here we emphasize the need to consider chronic exposure to carbon monoxide as a potentially reversible cause of sensorineural hearing loss if diagnosed and treated early.

Raised intracranial pressure and seizures in the neurological intensive care unit

BACKGROUND

The relationship between changes in intracranial pressure and incidence of subclinical seizures in patients requiring neurological intensive care is not fully understood. The aim of this study was to investigate if acute increases in intracranial pressure were accompanied by subclinical seizures.

METHODS

We prospectively studied 17 intensive care patients (11 male, aged 3-66 yr) who were selected from 85 patients requiring intracranial pressure measurement. Patients were selected to have a 30 min, 16-channel electroencephalogram (EEG) recorded when intracranial pressure remained increased despite preliminary treatments.

RESULTS

Diagnoses included head injury, intracranial haemorrhage, subarachnoid haemorrhage and sagittal sinus thrombosis. All patients had at least one acute episode of intracranial pressure increase. Pressures ranged from 90 to 440 mm H(2)O. Encephalopathic features (delta/theta rhythms and burst suppression) were noted on all EEGs. No seizure activity was recorded.

CONCLUSIONS

We conclude from this pilot study that seizures are an uncommon cause of acute raised intracranial pressure. To determine whether raised intracranial pressure causes seizures, long-term monitoring in a large cohort of intensive care patients would be necessary, studying patients with similar diagnoses and ages.

Heavy users of acute psychiatric beds: randomized controlled trial of enhanced community management in an outer London borough

BACKGROUND

Heavy users of psychiatric services, often defined as the population that uses the most beds, consume a large part of the resources used by the whole service, despite being relatively small in number. Any intervention that reduces heavy use is therefore likely to lead to significant savings, and enhancement of standard care using a form of intensive case management akin to assertive community treatment was thought to be a pragmatic strategy for testing in this group.

METHODS

The effectiveness of enhanced community management (ECM) was compared with standard care alone in heavy users, who represented the 10% of patients with the highest number of hospital admissions and occupied bed days over the previous 6.5 years in an outer London borough. One hundred and ninety-three patients were randomly assigned to ECM or standard care and their use of services was determined after 1 and 2 years, with assessments of costs, clinical symptoms, needs, and social function made before entry into the study and after 1 and 2 years.

RESULTS

Despite a 24 fold increase in community contacts in the study group, there were no significant differences between the two groups in any of the main outcome measures. Small savings on in-patient and day-hospital service costs were counterbalanced by the increased costs of outpatient and community care for the subjects assigned to ECM. Clinical outcome data derived from interviews in two-thirds of the subjects were similar in both groups.

CONCLUSIONS

Providing additional intensive community focused care to a group of heavy users of psychiatric in-patient services in an outer London borough does not lead to any important clinical gains or reduced costs of psychiatric care.

Posterior segment approach for subretinal transplantation or injection in the canine model

A posterior segment approach for cell transplantation or injection into the subretinal space of the dog has been developed. Controlled penetration to the subretinal space was achieved using a 29-gauge injection cannula, either blunted or with a 30 degrees sharpened bevel, and partially ensheathed with moveable plastic tubing. Depending on the injection volume used, the retina detached, and the fluid was reabsorbed within 1-3 weeks, although for smaller volumes the retina reattached within a matter of days. The optimal injection volume used was between 100 and 150 microl, or two injections of 55 microl each. By ophthalmoscopy following the surgery, it was possible to serially monitor the injection site and retinal bleb through fundus photography. Light microscopy demonstrates the distribution of stable, viable RPE cells in the subretinal space up to 6 months. The transplantation technique developed for the dog is atraumatic and free from any major surgical or clinical complications. It can be readily used to deliver cells or fluids to localized regions of the subretinal space.

Functional outcomes of orofacial myofunctional therapy in children with cerebral palsy

Though some anecdotal evidence supports the efficacy of orofacial myofunctional therapy in cerebral palsy and other disorders, controlled studies are very scant. This study was undertaken to examine the efficacy of orofacial myofunctional therapy in sixteen children diagnosed with spastic cerebral palsy. Following baseline measures, all children participated in a four-month therapy program, consisting of training the tongue, lips, and jaw muscles for adequate posturing and functioning. Post-therapy measures indicated significant improvement in functioning of lips, tongue, and jaw. Speech intelligibility of words also improved significantly as measured by two judges using a five-point rating scale. A significant correlation was found between tongue functioning and improvement in speech intelligibility; however no significant correlation was obtained between functioning of lips/jaw and speech intelligibility. Clinical implications regarding use of orofacial myofunctional therapy with cerebral palsied children are discussed.

Adenoviral vector-mediated beta-glucuronidase cDNA transfer to treat MPS VII RPE in vitro

PURPOSE

To develop an effective therapy for treating glycosaminoglycan (GAG) storage in mucopolysaccharidosis VII (MPS VII) retinal pigment epithelium (RPE) in vitro using adenoviral vector mediated human beta-glucuronidase cDNA (Ad-GUSB) transfer.

METHODS

Ad-GUSB was used to infect RPE at confluency. The transduction condition was optimized varying time of infection and number of infectious particles. The beta-glucuronidase (GUSB) activity was measured in transduced cells and media using a fluorogenic substrate. The GAG profiles were examined by metabolically labeling RPE with (35)Na(2)SO(4).

RESULTS

Transduced RPE, irrespective of species or disease status, expressed a high level of beta-glucuronidase. The expressed enzyme restored normal levels of GAGs in the RPE cells of homozygous affected MPS VII dogs by metabolizing stored GAGs. The over-expressed enzyme (>10 000 nmoles/hr/mg) failed to restore normal level of GAGs. A high level of GUSB expression was maintained in vitro at least nine weeks.

CONCLUSIONS

Adenoviral vector could mediate transfer of GUSB in MPS VII affected RPE and RPE of various species, and the expression was observed to be stable in vitro. However, controlled expression of GUSB was essential for the metabolism of stored GAGs to achieve normal levels.

A physician-pharmacist model for the surveillance of blood pressure in the community: a feasibility study

Hypertension is poorly managed. Hospital-based pharmacists working with physicians have been shown to improve the rate of achievement of "target" blood pressure in selected patients. It is unknown if such schemes can operate in the community and to what extent they would attract volunteers with poorly managed blood pressure. We assessed the feasibility of pharmacists to provide community-based, open-access, blood pressure monitoring. In addition, we describe the blood pressure profile of the group in comparison to that of the 1994 Health Survey of England (HSE). Pharmacists from six pharmacies were trained to deliver the service. Adults living within the postal districts of the pharmacies were invited, through an advertising campaign, to volunteer to have their blood pressure measured. Blood pressure data and information on treatment for hypertension and/or diabetes were collected on 263 registrants. Patients were advised to have their blood pressure managed by the general practitioner immediately (category 1), re-measured within 2-3 months (category 2) or in 12 months time (category 3). The mean (s.d.) blood pressure of patients in categories 1 (n = 16), 2 (n = 117) and 3 (n = 130) was 186(16)/97(29), 151(13)/94(9) and 139(22)/86(13) mm Hg respectively; P < 0.001. Ninety-one patients (35%) were in receipt of antihypertensive therapy. Forty-five percent of the treated group had controlled blood pressure (<160/95 mm Hg) compared with 30% in the HSE dataset. A large proportion of known hypertensive patients with poor blood pressure control who had visited their general practitioner within the previous 6 months were detected by the pharmacist-led service. Pharmacists operating an open-access blood pressure monitoring service may be of value in improving the management of hypertension.

Long-chain acyl-coenzyme A esters and fatty acids directly link metabolism to K(ATP) channels in the heart

ATP-sensitive K (K(ATP)) channels are inhibited by cytosolic ATP, a defining property that implicitly links these channels to cellular metabolism. Here we report a direct link between fatty acid metabolism and K(ATP) channels in cardiac muscle cells. Long-chain (LC) acyl-coenzyme A (CoA) esters are synthesized from fatty acids and serve as the principal metabolic substrates of the heart. We have studied the effects of LC acyl-CoA esters and LC fatty acids on K(ATP) channels of isolated guinea pig ventricular myocytes and compared them with the effects of phosphatidylinositol 4,5-bisphosphate (PIP(2)). Application of oleoyl-CoA (0.2 or 1 micromol/L), a naturally occurring acyl-CoA ester, to the cytosolic side of excised patches completely prevented rundown of K(ATP) channels, but not of Kir2 channels. The open probability of K(ATP) channels measured in the presence of oleoyl-CoA or PIP(2) was voltage dependent, increasing with depolarization. Oleoyl-CoA greatly reduced the ATP sensitivity of K(ATP) channels. At a concentration of 2 micromol/L, oleoyl-CoA increased the half-maximal inhibitory concentration of ATP >200-fold. The time course of the decrease in ATP sensitivity was much faster during application of oleoyl-CoA than during application of PIP(2). The effects of PIP(2), but not of oleoyl-CoA, were inhibited by increasing Ca(2+) to 1 mmol/L. Oleate (C18:1; 10 micromol/L), the precursor of oleoyl-CoA, inhibited K(ATP) channels activated by oleoyl-COA: Palmitoleoyl-CoA and palmitoleate (C16:1) exerted similar reciprocal effects. These findings indicate that LC fatty acids and their CoA-linked derivatives may be key physiological modulators of K(ATP) channel activity in the heart.

Gene therapy restores vision in a canine model of childhood blindness

The relationship between the neurosensory photoreceptors and the adjacent retinal pigment epithelium (RPE) controls not only normal retinal function, but also the pathogenesis of hereditary retinal degenerations. The molecular bases for both primary photoreceptor and RPE diseases that cause blindness have been identified. Gene therapy has been used successfully to slow degeneration in rodent models of primary photoreceptor diseases, but efficacy of gene therapy directed at photoreceptors and RPE in a large-animal model of human disease has not been reported. Here we study one of the most clinically severe retinal degenerations, Leber congenital amaurosis (LCA). LCA causes near total blindness in infancy and can result from mutations in RPE65 (LCA, type II; MIM 180069 and 204100). A naturally occurring animal model, the RPE65-/- dog, suffers from early and severe visual impairment similar to that seen in human LCA. We used a recombinant adeno-associated virus (AAV) carrying wild-type RPE65 (AAV-RPE65) to test the efficacy of gene therapy in this model. Our results indicate that visual function was restored in this large animal model of childhood blindness.

A randomized trial of nelfinavir, ritonavir, or delavirdine in combination with saquinavir-SGC and stavudine in treatment-experienced HIV-1-infected patients

PURPOSE

To evaluate the 24-week impact of saquinavir-enhancing antiretroviral therapy on viral replication in patients previously treated with nucleoside analogues with or without prior saquinavir hard-gel capsules (HGC).

METHOD

Patients were randomized in three groups to receive the following: Group 1-nelfinavir (750 mg tid), saquinavir soft-gel capsule (SGC) (800 mg tid), and stavudine (40 mg bid); Group II-ritonavir (400 mg bid), saquinavir-SGC (400 mg bid), and stavudine (40 mg bid); or Group III-delavirdine (400 mg tid), saquinavir-SGC (800 mg tid), and stavudine (40 mg bid). Viral loads, CD4 count, and safety were assessed over a 24-week period with an additional 6-month follow-up.

RESULTS

73 patients received randomized therapy; 14 of whom were SQV naïve, with a median baseline viral load of 3.6 log(10) and a CD4 count of 370 cells/mm(3). By 6 months, the median decreases in plasma viral loads were 0.26, 0.71, and 0.29 log(10) copies/mL for groups I, II, and III, respectively. The median increases in CD4 counts, for groups I, II, and III, were 52, 40, and 69 cells/mm(3) at 6 months, respectively. Changes in viral load and CD4 counts at 6 months and 1 year were not significantly different between the treatment groups. More patients discontinued therapy in the ritonavir arm (35%) for drug intolerance or toxicity compared to either the nelfinavir or delavirdine arms (15% and 5%, respectively). In a multivariate analysis, baseline viral load, younger age, and baseline saquinavir resistance were significantly associated with detectable viral load at 24 weeks.

CONCLUSION

The use of antiretroviral agents that pharmacokinetically boost saquinavir levels has a modest benefit in saquinavir-experienced patients.

Ataxia telangiectasia mutated is essential during adult neurogenesis

Ataxia telangiectasia (A-T) is an autosomal recessive disease characterized by normal brain development followed by progressive neurodegeneration. The gene mutated in A-T (ATM) is a serine protein kinase implicated in cell cycle regulation and DNA repair. The role of ATM in the brain and the consequences of its loss on neuronal survival remain unclear. We studied the role of ATM in adult neural progenitor cells in vivo and in vitro to define the role of ATM in dividing and postmitotic neural cells from Atm-deficient (Atm(-/-)) mice in a physiologic context. We demonstrate that ATM is an abundant protein in dividing neural progenitor cells but is markedly down-regulated as cells differentiate. In the absence of ATM, neural progenitor cells of the dentate gyrus show abnormally high rates of proliferation and genomic instability. Atm(-/-) cells in vivo, and in cell culture, show a blunted response to environmental stimuli that promote neural progenitor cell proliferation, survival, and differentiation along a neuronal lineage. This study defines a role for ATM during the process of neurogenesis, demonstrates that ATM is required for normal cell fate determination and neuronal survival both in vitro and in vivo, and points to a mechanism for neuronal cell loss in progressive neurodegenerative diseases.

A prodrug approach to the design of cRaf1 kinase inhibitors with improved cellular activity

Earlier we reported potent cRaf1 kinase inhibitors with a key acidic phenol pharmacophore that had, at best, adequate cellular efficacy. To improve the cellular potency, phenol isosteres and prodrugs were investigated. Many phenol isosteres were synthesized and tested, but failed to provide adequate enzyme potency. A prodrug approach resulted in a 2- to 17-fold improvement over the parent compound in cell-based efficacy.

Costs and characteristics of heavy inpatient service users in outer London

"Heavy users" is a new term often used to describe those who occupy a disproportionate number of psychiatric beds. In this study we identified the heaviest 10% (193) inpatient service users in one London borough over a 6 year period and compared these with a control group of 400 ordinary inpatient users. A weighting index was used to combine frequency of admission with duration. Heavy users were diagnostically and demographically similar to ordinary inpatient service users and only differed by their extensive use of services, about 3 times more than ordinary users in terms of health care costs, during the measured year. Their heavy use mainly depended on occupying hospital beds, and their use of outpatient, day patient and community services was relatively light.

Adult spinal cord stem cells generate neurons after transplantation in the adult dentate gyrus

The adult rat spinal cord contains cells that can proliferate and differentiate into astrocytes and oligodendroglia in situ. Using clonal and subclonal analyses we demonstrate that, in contrast to progenitors isolated from the adult mouse spinal cord with a combination of growth factors, progenitors isolated from the adult rat spinal cord using basic fibroblast growth factor alone display stem cell properties as defined by their multipotentiality and self-renewal. Clonal cultures derived from single founder cells generate neurons, astrocytes, and oligodendrocytes, confirming the multipotent nature of the parent cell. Subcloning analysis showed that after serial passaging, recloning, and expansion, these cells retained multipotentiality, indicating that they are self-renewing. Transplantation of an in vitro-expanded clonal population of cells into the adult rat spinal cord resulted in their differentiation into glial cells only. However, after heterotopic transplantation into the hippocampus, transplanted cells that integrated in the granular cell layer differentiated into cells characteristic of this region, whereas engraftment into other hippocampal regions resulted in the differentiation of cells with astroglial and oligodendroglial phenotypes. The data indicate that clonally expanded, multipotent adult progenitor cells from a non-neurogenic region are not lineage-restricted to their developmental origin but can generate region-specific neurons in vivo when exposed to the appropriate environmental cues.

Fibroblast growth factor-2-producing fibroblasts protect the nigrostriatal dopaminergic system from 6-hydroxydopamine

We tested the hypothesis that fibroblasts, which had been genetically engineered to produce fibroblast growth factor-2 (FGF-2), can protect nigrostriatal dopaminergic neurons. Three groups of rats received either a burr hole only (n=5) or implantation of fibroblasts, which had been genetically engineered to produce beta-galactosidase (beta-gal) (n=8) or FGF-2 (n=8), at two sites in the right striatum. Two weeks later, the animals received an injection of 25 microg of 6-hydroxydopamine hydrobromide (6-OHDA) midway between the two implant sites. The group that received FGF-2-fibroblasts had significantly fewer apomorphine-induced rotations than the groups that received a burr hole only or beta-gal-fibroblasts at weeks 2 and 3 following lesioning with 6-OHDA. Testing for amphetamine-induced rotation revealed a mild reduction in rotation in the beta-gal-fibroblast group compared to the burr hole only group, but a striking attenuation of amphetamine-induced rotation in the FGF-2-fibroblast group. There was also preservation of TH-IR neurons on the lesioned side relative to both control groups. The size of the grafts and the gliosis surrounding the injection sites did not differ between the FGF-2-fibroblast and beta-gal-fibroblast groups. To further characterize the production of FGF-2 by the FGF-2-fibroblasts, we implanted FGF-2-fibroblasts and beta-gal-fibroblast into the striatum of rats but did not lesion the animals with 6-OHDA. The animals were then sacrificed at 1, 2 and 5 weeks following implantation. Prior to implantation the FGF-2 fibroblasts contained 148 ng/mg of FGF-2-immunoreactive (FGF-2-IR) material per mg of protein of cell lysate. After implantation FGF-2-IR material was noted in the grafts of FGF-2-fibroblasts, most conspicuously at 1 and 2 weeks following implantation. We also noted FGF-2-IR material in the nuclei of reactive astrocytes adjacent to the implants, and OX-42-immunoreactive (OX-42-IR) cells adjacent and occasionally within the implants. Our work indicates that fibroblasts genetically engineered to produce FGF-2 and implanted in the striatum can protect the nigrostriatal dopaminergic system and may be useful in the treatment of Parkinson's disease.

FGF-2-responsive neural stem cell proliferation requires CCg, a novel autocrine/paracrine cofactor

We have purified and characterized a factor, from the conditioned medium of neural stem cell cultures, which is required for fibroblast growth factor 2's (FGF-2) mitogenic activity on neural stem cells. This autocrine/paracrine cofactor is a glycosylated form of cystatin C (CCg), whose N-glycosylation is required for its activity. We further demonstrated that, both in vitro and in vivo, neural stem cells undergoing cell division are immunopositive for cystatin C. Finally, we showed in vivo functional activity of CCg by demonstrating that the combined delivery of FGF-2 and CCg to the adult dentate gyrus stimulated neurogenesis. We propose that the process of neurogenesis is controlled by the cooperation between trophic factors and autocrine/paracrine cofactors, of which CCg is a prototype.

Computerized cochlear implant database system

In an environment of clinical governance with increased demands for accountability it is very important that accurate, reliable and secure data records be maintained for easy retrieval, analysis and presentation when required. A database is a very versatile tool for this purpose. We describe here our experience in designing a database for cochlear implant patients in Cambridge, together with guidance for prospective designers in their chosen sub-specialty.

Cloning and expression of type II collagen mRNA: evaluation as a candidate for canine oculo-skeletal dysplasia

The disease phenotype of oculo-skeletal dysplasia (OSD) detected in Labrador retrievers and Samoyeds shows a large degree of similarity with human Stickler and Kniest dysplasia. Type II collagen (COL2A1) mRNA, which is defective in a larger number of Stickler and Kniest patients, has been cloned and characterized from normal dog. The amino acid sequence of the canine type II procollagen is predicted to contain 1487 residues, with high degree of homology with its human homologue, and maintains all the characteristic structural domains. In addition to cartilage, expression of COL2A1 has also been detected in canine retina and testes. In testes, the N-propeptide region of COL2A1 displayed differential splicing and expressed both splice variants, IIA (with exon 2) and IIB (without exon 2), suggesting the importance of both forms in testis maturation and maintenance. Despite a severe decrease of type II collagen protein in the vitreous of OSD affected Labrador retrievers, COL2A1 gene has been excluded from having any causal association with the disease locus by linkage analysis. Using an intragenic RFLP marker, COL2A1 gene has also been tested as a candidate gene for the non-allelic form of the other canine OSD identified in Samoyeds, and excluded by linkage analysis. Oculo-skeletal dysplastic Labrador retriever and Samoyed provide two animal models for chondrodysplasia with genetic heterogeneity.

Neuronal differentiation and morphological integration of hippocampal progenitor cells transplanted to the retina of immature and mature dystrophic rats

Attempts to repopulate the retina with grafted neurons have been unsuccessful, in large part because donor cells prefer not to integrate with those of the host. Here we describe the first use of neural progenitor cells in the diseased adult retina. Adult rat hippocampal progenitor cells were injected into the eyes of rats with a genetic retinal degeneration. After survival times up to 16 weeks, the retinae of 1-, 4-, and 10-week-old recipients exhibited widespread incorporation of green fluorescent protein-expressing (GFP+) donor cells into the host retina. The 18-week-old recipients showed a similar pattern, but with fewer cells. Grafted cells expressed the mature neuronal markers NF-200, MAP-5, and calbindin. GFP+ cells extended numerous neurites into the host plexiform layers and these processes were intimately associated with synaptophysin+ profiles. GFP+ neurites also extended into the host optic nerve head. These results demonstrate the differentiation of substantial numbers of new neurons within the mature dystrophic retina.

The fate of manuscripts rejected by a general medical journal

PURPOSE

The fate of research manuscripts that have been rejected by medical journals is of interest to authors, editors, and peer reviewers, but previous studies were conducted before the widespread availability of computerized literature searches. We update the previous investigations of the fate of rejected research manuscripts by using an electronic literature search and a larger sample, a longer follow-up, and more descriptive journal indexes.

METHODS

Using a retrospective cohort study design, we examined 350 manuscripts rejected by the Annals of Internal Medicine, a general medical journal, during 1993 and 1994. We assessed the number of manuscripts that were published after initial rejection, time to eventual publication, journal type (general versus specialty), and journal impact factor (higher scores indicated greater impact) and immediacy index.

RESULTS

Of 350 rejected manuscripts, 240 (69%, 95% confidence interval [CI]: 64% to 73%) were eventually published after a mean of 552 days (95% CI: 479 to 544 days, range 121 to 1, 792 days). Of 226 rejected research articles and reviews, 159 (70%, 95% CI: 64% to 76%) were subsequently published in specialty journals. During 1993 and 1994, the mean impact factor for articles published in the Annals was 9.60 (95% CI: 9.56 to 9.64), compared with a mean of 3.09 (95% CI: 2.80 to 3.37) for the journals in which the rejected articles were subsequently published (mean difference 6. 52, 95% CI: 6.24 to 6.81, P < 0.0001). The immediacy index was also lower for these journals. Time to publication had a weak negative correlation with the impact factor of the journal in which the article was published (correlation coefficient -0.15, P = 0.007).

CONCLUSIONS

The majority of the manuscripts that were rejected from a large general medical journal were eventually published after an average of 18 months. Most were published in specialty journals with lower impact factor and immediacy index ratings.

Genetic characterization of gram-positive homologs of the XerCD site-specific recombinases

Homologs of the XerCD enzymes, which in Escherichia coli have been shown to be responsible for resolving chromosomal multimers prior to chromosome segregation, were identified in the genomes of Staphylococcus aureus and Streptococcus pneumoniae. Phylogenetic and conservation pattern analysis suggests that the S. aureus gene products are orthologs of XerC and D. A S. aureus xerC null mutant displayed in vitro characteristics consistent with the segregation defect reported for E. coli xer mutants, and was found to be attenuated in a murine infection model. Strikingly, the S. aureus xerD gene appears to be absolutely required for viability, and may therefore be the first example of an essential gene of the lambda integrase family. In contrast, phylogenetic and conservation pattern analysis show that the S. pneumoniae gene products are more closely related to phage integrases than to XerCD. S. pneumoniae xer1, 2 and 3 null mutants were each found to be attenuated in a murine infection model, suggesting that they may control processes which affect virulence.

Two distinct mutations cause severe hemophilia B in two unrelated canine pedigrees

The molecular defects causing severe factor IX deficiency were identified in two distinct canine breed-variants. Both defects were associated with an absence of plasma factor IX coagulant activity and antigen. A large deletion mutation was found in 1 breed variant, spanning the entire 5' region of the factor IX gene extending to exon 6. An approximately 5 kb insertion disrupted exon 8 of the second breed-variant. This insertion was associated with alternative splicing between a donor site 5' and acceptor site 3' to the normal exon 8 splice junction, with introduction of a new stop codon. The resultant transcript lacked most of the factor IX catalytic domain and 3' untranslated region. Molecular analyses of canine hemophilia B define an experimental model for study of inhibitor formation and gene therapy strategies, and provide insight into spontaneous mutation mechanisms in the factor IX gene and on the X chromosome of mammalian species.

Further experience with fat graft obliteration of mastoid cavities for cochlear implants

Obliteration of old mastoids and wet middle ears with autologous abdominal fat seems to be a reliable technique to render chronically discharging mastoid cavities or open middle ears dry and closed. This paper is the third in the series and looks at the intermediate results at five years. Of the 16 patients (one bilateral) 94.1 per cent of the ears are still dry and uninfected with closed external meati. Recurrent cholesteatoma was found in two patients at implantation and removed.

Synthesis and release of docosahexaenoic acid by the RPE cells of prcd-affected dogs

PURPOSE

Dogs affected with progressive rod-cone degeneration (prcd) have reduced levels of docosahexaenoic acid (DHA, 22:6n-3) in their plasma and rod photoreceptor outer segments (ROS). Dietary supplementation of DHA has failed to increase the ROS DHA levels to that of unaffected control dogs. The present study was undertaken to test the hypothesis that prcd-affected dogs have a reduced capacity for the synthesis and/or release of DHA in retinal pigment epithelial (RPE) cells.

METHODS

RPE cells (first passage cultures) from prcd-affected and normal dogs were incubated with [3H]eicosapentaenoic acid (EPA, 20:5n-3) for 24 and 72 hours. After incubation, the radiolabeled fatty acids in the cells and media were analyzed.

RESULTS

DHA and all its metabolic intermediates were detected in RPE cells from prcd-affected and normal dogs. No significant difference was found in the amount of products (including DHA) synthesized between normal and affected RPE cells at either time point. In the culture media, RPE cells from prcd-affected dogs released significantly more DHA than cells from normal dogs after 72-hour incubation, but not after 24-hour incubation.

CONCLUSIONS

RPE cells from prcd-affected dogs can synthesize and release DHA at least as efficiently as cells from normal dogs. Therefore, synthesis of DHA from its precursor and its release from RPE cells does not appear to contribute to the reduction in ROS DHA levels found in prcd-affected animals.

Calcium metabolism in pre-eclampsia

OBJECTIVES

To study calcium metabolism in pre-eclampsia and normotensive gravid women.

METHOD

Ten milliliters of heparinized blood samples and 24-h urine samples were collected from 50 pre-eclamptic and 50 normotensive primigravidae. Blood samples were studied for calcium uptake, intracellular calcium level and calcium-dependent adenosine triphosphatase activity of red blood cell ghost. Urinary calcium excretion was estimated from the 24-h urine samples. These values were compared in the two groups.

RESULTS

The mean gestational age at recruitment was similar in both the groups. The mean maternal age was 24.28 +/- 2.41 years in pre-eclamptic and 23.48 +/- 4.16 years in normotensive women. In pre-eclampsia 24-h urinary calcium excretion (71.20 +/- 22.95 mg/day) and calcium-dependent ATPase activity (10.78 +/- 2.40 nmol/Pi/mg protein/min) was significantly lower compared to normotensive primigravidae (calcium excretion = 189.24 +/- 57.06 mg/day; Ca2+-dependent ATPase = 12.64 +/- 2.42 nmolPi/mg /protein per min; P < 0.001). Intracellular calcium levels and calcium uptake at 10 min by red blood cells were significantly higher in pre-eclampsia (P < 0.05). Calcium uptake by red blood cells at 20 and 30 min was similar in both groups.

CONCLUSION

Pre-eclampsia is associated with increased levels of intracellular calcium, decreased calcium-dependent ATPase activity of erythrocytes and hypocalciuria.

Rapidly invading sebaceous carcinoma of the external auditory canal

A very rare case of a sebaceous carcinoma of the external auditory canal with basal cell differentiation is presented. Fewer than 400 cases affecting any part of the body have so far been reported and of that only seven cases have been known to involve the external auditory canal. The clinical features, pathology and treatment are described and the relevant literature has been reviewed.