Cortical deficits in multiple sclerosis on the basis of subcortical lesions

Patients suffering from multiple sclerosis have a high frequency of cognitive deficits usually attributable to demyelination and axonal loss in the subcortical white matter. Neurologic abnormalities referable to cortical function are uncommon but have been described. The present study describes three patients with clinically definite MS with deficits in cognitive function referable to cortical location. Two of the patients underwent positron emission tomography and showed profound cortical hypometabolism adjacent to subcortical white matter lesions seen on MRI. This paper points out that neurologic deficits referable to cortical sites may be caused by subcortical white matter lesions and that cognitive dysfunction in patients with MS may progress rapidly in the absence of motoria deficits or other evidence of clinical deterioration. Multiple Sclerosis (2000) 6 50 - 55

A direct comparison of cytolytic T-lymphocyte responses to Melan-A peptides in vitro: differential immunogenicity of Melan-A27-35 and Melan-A26-35

In this study we directly compared the in vitro responses of T-cells from normal donors and melanoma patients to Melan-A27-35 and Melan-A26-35. These peptides have been previously used in peptide-based vaccination studies. Following three stimulations with peptide-pulsed antigen-presenting cells in vitro, Melan-A-specific cytolytic T-lymphocytes (CTLs) were generated from seven of 20 subjects; two of the seven subjects responded reproducibly to both Melan-A27-35 and Melan-A26-35, three to only Melan-A27-35 and two to only Melan-A26-35. However, CTLs generated with either Melan-A27-35 or Melan-A26-35 showed cross recognition, and both types of CTL could recognize naturally processed antigen displayed on HLA-A2+ tumour cells. Furthermore, Melan-A-specific CTLs could also be generated by stimulating peripheral blood mononuclear cells with autologous melanoma cells. Our results suggest that some subjects may have a bias in their CTL repertoire which favours the generation of Melan-A27-35 specific CTLs, while others may favour Melan-A26-35 specific CTLs. It is also likely that CTL precursors capable of detecting both peptides may have different affinities to the two Melan-A peptides. Since it is difficult to predict the CTL responses to Melan-A peptide in a given individual, we suggest vaccinating with both Melan-A27-35 and Melan-A26-35 peptides in clinical trials.

Depression in young people. A growing challenge for primary care

BACKGROUND

Recent research indicates that 27% of young people aged 18-24 have a mental health problem involving mood, anxiety, personality and/or substance abuse disorders and 15-40% report depressive symptomatology. A proportion of these young people will suicide. The morbidity associated with depressive illness in this age group is high, with those experiencing a depressive episode having reduced vocational and life prospects and being highly vulnerable to further episodes in later life.

OBJECTIVE

To outline the clinical features of depression in young people and to provide strategies for appropriate management.

DISCUSSION

Presentation of depression in young people is likely to vary from accepted diagnostic criteria with non specific symptoms such as boredom, anxiety, failing adjustment and sleep disturbance predominating. Management includes attending to key social problems, ensuring a safe environment and counselling, which may be supportive counselling or more specific treatments of cognitive behavioural therapy or interpersonal psychotherapy. Medication is indicated for more severe depression or with failure of response to psychological strategies. Early case identification and intensive treatment of first episodes of depression is important in reducing prevalence, cost and morbidity.

Transscleral diode laser in the treatment of retinopathy of prematurity

PURPOSE

To assess the outcome of contact transscleral diode laser (TSDL) in the treatment of threshold retinopathy of prematurity (ROP).

METHOD

TSDL was performed in 14 eyes of 8 babies who presented to the paediatric ophthalmic service at King's College Hospital between 1996 and 1997 with threshold ROP (median post-conceptual age 26 + 1 weeks, median birthweight 835 g) by a single surgeon. Follow-up ranged from 9 to 41 weeks (median 21 weeks).

RESULTS

In 11 eyes (79%) regression of ROP occurred after a single laser treatment with a good anatomical outcome. In 3 eyes (21%) there was an unfavourable response with the development of traction retinal detachment. These include both eyes of one baby who rapidly progressed to stage IV ROP. One other eye developed a fibrotic band a few months after treatment. No significant complications of laser treatment were observed.

CONCLUSION

These initial results indicate that TSDL photocoagulation is an effective and technically straightforward alternative to cryotherapy in the treatment of ROP.

An investigation of attributional style in first-episode psychosis

OBJECTIVE

The present study investigated covert and overt attributional styles in individuals experiencing a first episode of psychosis. It was hypothesized that those individuals experiencing paranoia, as operationalized by higher scores on the suspiciousness item of the Brief Psychiatric Rating Scale (BPRS) would perform differently on both covert and overt measures of attributional style when compared to those individuals who scored lower on the BPRS suspiciousness item.

DESIGN AND METHODS

A cross-sectional design was used. The sample consisted of 62 participants (50 males and 12 females) from the Early Psychosis Prevention and Intervention Centre. The Pragmatic Inference Task (PIT) was used to measure covert attributional style, whereas the Attributional Style Questionnaire (parallel form; ASQpf) measured overt attributional style. The Rosenberg Self-Esteem Questionnaire measured global self-esteem. Participants' positive, negative, and depressive symptoms were assessed by means of the BPRS, the Scale for the Assessment of Negative Symptoms, and the Beck Depression Inventory, respectively.

RESULTS

Regression analyses found that less suspiciousness (p = .02) and more depression (p = .02) predicted higher internal attributions for negative events scores on the ASQpf. There was a trend (p = .07) for more suspicious individuals to endorse the self-serving bias (SSB) on the PIT, even despite the SSB not being large enough to be considered defensive. Verbal IQ emerged as a significant predictor of covert attributional style (p = .04).

CONCLUSIONS

The findings suggest that increasing suspiciousness does predict attributional style in the early stages of psychosis, although the relationship appears weaker than in reports with more chronic psychotic patient samples. Longitudinal research is needed to ascertain whether attributional style is a stable characteristic in psychosis, or whether it fluctuates between periods of remission and active psychosis.

The molecular basis of transferase galactosaemia in South African negroids

Transferase galactosaemia is an autosomal recessively inherited disorder caused by a deficiency of galactose-1-phosphate uridyltransferase (GALT). Manifestations include jaundice, vomiting, cataracts, mental retardation, speech abnormalities and poor growth. The GALT gene has been mapped and sequenced. The S135L mutation accounts for approximately 48% of galactosaemia alleles in African Americans and has been found to account for about 91% of galactosaemia alleles in negroid South African patients which suggested that the mutation had an African origin. We have calculated the S135L allele frequency (+/- 1SE) in a sample of healthy unrelated negroid South Africans to be 0.0067 (+/- 0.0024). The S135L mutation was also detected in negroid populations from other regions of Africa confirming its African origin.

The cost of home-based care for HIV/AIDS patients in Zimbabwe

From a study on the cost and quality of community home-based care (CHBC) for HIV/AIDS patients in Zimbabwe, programme and household costs were estimated. Interviews, using a structured questionnaire, were held with 60 patients and caregivers sampled from six types of established CHBC schemes. Detailed cost information was collected from four home care programmes, two urban and two rural. The cost of a home visit in the two urban programmes studied was estimated to be Z$129 (US$16) in one, and Z$183 (US$23) in the other. In one of the two rural schemes, the cost of a home visit was Z$313 (US$38), in the other this was Z$343 (US$42). A large proportion of these costs were not of direct benefit to the patients, as approximately 56-75% of the total cost per home visit was spent getting to the patient. The costs of a home visit in a rural home-based care programme corresponded to the costs of 2.7 inpatient days in a district hospital. The family cost of caring for a bedridden AIDS patient over a three-month period was estimated to be between Z$556-841. Caregivers spent as much as 2.5-3.5 hours a day on routine patient care. The programme costs are high, and schemes do not generally assess effectiveness, nor cost-effectiveness. The high cost of home visits leads to less frequent visits, leaving a larger part of both the burden and the cost of care to the families and the patients.

Cognitively-oriented psychotherapy for early psychosis (COPE). Preliminary results

BACKGROUND

The present study describes the results of the pilot testing of a therapy we have developed for people with first-episode psychosis. Cognitively-oriented psychotherapy for early psychosis (COPE) is aimed at facilitating the adjustment of the person, and at preventing or alleviating secondary morbidity in the wake of the first psychotic episode.

METHOD

Eighty people formed three groups: those who were offered and accepted COPE (COPE subjects); those who refused COPE (refusal subjects); and those who were offered neither COPE nor any other continuing treatment from our service (control subjects). The individuals were assessed prior to, and at the end of, COPE treatment (a 12-month period) on the Integration/Sealing Over, Explanatory Model, Scale for the Assessment of Negative Symptoms, Brief Psychiatric Rating Scale, Quality of Life, SCL-90-R, and Beck Depression Inventory measures.

RESULTS

People who received COPE obtained significantly superior scores (P < 0.05) to the control group on four of the seven measures but only significantly out-performed the refusal group on one of the seven measures (P < 0.05). The COPE group performed significantly worse on the BDI than the refusal group (P < 0.05). Effect sizes are also provided for each measure.

CONCLUSIONS

There seems to be a place for psychological therapy in this group of people but our results need to be replicated in a more definitive randomised controlled trial and such a study is now in progress.

Antigen specificity and tumour targeting efficiency of a human carcinoembryonic antigen-specific scFv and affinity-matured derivatives

We have examined the biological properties of CEA6, a human carcinoembryonic antigen (CEA)-specific single-chain Fv (scFv) isolated by phage display, and five related clones derived by affinity maturation and selected for improved off-rate (Koff). All clones bind strongly and specifically to CEA-positive human tumours by immunocytochemistry and show negligible cross-reactivity with normal colon. Flow cytometry of scFv on human liver cells indicates a shift in fine epitope specificity resulting from mutagenesis. All monomeric scFv have been radioiodinated, retaining effectively full binding activity. A single intravenous injection into nude mice bearing human colon tumour xenografts confirms tumour targeting in all cases. As reported in other studies, the kidney is the main route of elimination of scFv at early time points. Tumour binding of the parental antibody CEA6 consistently gives the highest tumour-blood ratios at 24 h (mean 16:1). Clone TO6D11, which has a sevenfold reduced Koff relative to CEA6, showed no difference in tumour uptake at 24 h but persisted at the tumour site for longer than CEA6. This study demonstrates a possible correlation between binding affinity and tumour residence time when examined in this model.

Flow cytometric apoptosis assays indicate different types of endonuclease activity in haematopoietic cells and suggest a cautionary approach to their quantitative use

Two flow cytometric apoptosis assays, the terminal deoxynucleotidyl transferase (TdT) assay and in situ nick translation (ISNT) assay, were assessed for their ability to quantitate drug-induced apoptosis in CLL lymphocytes. In contrast to HL60 cells, biotinylated dUTP could not be effectively incorporated into apoptotic CLL lymphocytes using exogenous TdT. This suggested that CLL lymphocytes possess a different type of endonuclease that cleaves DNA, leaving blunt or 3' recessed DNA breaks, which are poor substrates for TdT. This possibility was tested using lambda exonuclease, which can convert a blunt or 3' recessed DNA break into a 3' overhang. Apoptotic CLL lymphocytes pre-treated with lambda exonuclease demonstrated increased nucleotide incorporation with TdT. Single-strand DNA breaks are also present in apoptotic CLL lymphocytes, as labelled nucleotides could be incorporated using the in situ nick translation assay. This study suggests that the efficiency of tailing reactions may be limited by the nature of the endonuclease activity in certain cell types and that validation with other parameters is an essential prerequisite to their quantitative use.

The relative population sizes of megakaryocytic cells in mouse bone marrow as determined by mpl ligand responsiveness

The relative population sizes of mpl ligand-responsive megakaryocytic cells were investigated, and all megakaryocytes grown in culture were assessed. Three groups were analyzed: 1) immature cells with the ability to form single mature megakaryocytes; 2) cells with the ability to divide once before forming megakaryocytes (doublets); and 3) progenitor cells with the ability to form colonies, i.e., to undergo both cytokinesis and maturation. Immature cells forming single megakaryocytes proved most sensitive to the mpl ligand. Committed megakaryocyte progenitors required approximately 30 times more mpl ligand to achieve maximum growth than did the immature megakaryocyte population. Similar numbers of committed megakaryocyte progenitors responded to interleukin (IL)-3 and to mpl ligand. The amplification potential of these progenitor cells responding to each growth factor was assessed by measuring the number of megakaryocytes per colony. In response to mpl ligand progenitor, cells generated smaller colonies, with most cell divisions completed at a signifcantly earlier time point compared with progenitor cells responding to IL-3. The growth of more primitive megakaryocyte progenitors was best achieved in combination with other growth factors, notably IL-3; mpl ligand alone was ineffective in this regard. A novel finding was the significant number of megakaryocytes that grew in culture as closely coupled pairs (doublets). Data reported indicate that doublet formation may be a result of detection and stimulation of immature megakaryocytes rather than the diminished mpl ligand responsiveness of a proportion of megakaryocyte progenitors. By combining the number of mpl ligand-responsive cells forming single megakaryocytes with those forming megakaryocyte doublets, it is estimated that the size of the immature megakaryocyte pool greatly exceeds previous calculations. Thus we conclude that the immature megakaryocyte population is significantly larger than previously estimated and that these cells are the most sensitive to mpl ligand. Accordingly, these cells are potentially crucial in bone marrow responsiveness to mpl ligand that results from acute thrombocytopenia, being capable not only of endomitosis and maturation but perhaps of cell division as well.

Use of pulsed irrigation evacuation in the management of the neuropathic bowel

Management of the neuropathic bowel is one of the major issues in the treatment of patients with severe spinal cord injury (SCI). Pulsed irrigation evacuation (PIE) has been evaluated in several small studies for the clearing of fecal impactions in patients with a neuropathic bowel. We evaluated our experience with 398 PIE procedures performed on inpatients and outpatients at our facility. It has proven to be both safe and effective in a wide variety of patients with this disorder, and is a useful addition to traditional methods in the management of the neuropathic bowel.

Absence of intrafamilial transmission of hepatitis C in patients with inherited bleeding disorders

Hepatitis 'C' virus (HCV) infection has caused significant anxiety in patients with inherited bleeding disorders. A significant number of patients with HCV have developed chronic liver disease, cirrhosis and hepatocellular carcinoma. The exact risk of heterosexual and contact transmission is unclear at the moment. A test for antibody to hepatitis 'C' was offered, after counselling, to spouses and family members of 118 known hepatitis 'C' antibody positive patients with inherited bleeding disorders. Two hundred and fifteen family members were tested, 73 partners and 142 household contacts; all were found negative for hepatitis 'C'. Our experience confirms the low risk of heterosexual and contact transmission of hepatitis 'C' virus.

Causes of blindness in northwest Cambodia

A hospital-based study in the northwest of Cambodia identified 453 blind adults and 30 blind children seen consecutively at the provincial ophthalmic department between January and September 1994. Blindness was defined as a visual acuity of less than 3/60 in the better eye. Cataract was the cause of blindness in 266 (59%) adults, of which 15 cases (3.3%) were surgical complications. Sixty-three cases (14%) were due to glaucoma and 53 (11.5%) patients had corneal scars, of which 12 (2.5%) were due to trachoma. Bilateral trauma, usually due to landmine injuries, accounted for 17 patients (4%). Of the 30 blind children, corneal scarring accounted for 12 cases (40%), congenital causes for 14 (47%) and optic atrophy secondary to meningitis for 4 (13%). There is at present an inadequate ophthalmological service for the vast majority of people living outside the capital Phnom Penh. These hospital-based data suggest that there is a need to train general doctors to surgically manage patients with visual loss from cataract and glaucoma, which together account for 70% of all cases of blindness, and highlight the need for a large population-based survey.

Covert poisoning with difenacoum: clinical and toxicological observations

1. The coumarin anticoagulant difenacoum was detected by high performance liquid chromatography (HPLC) with multi-wavelength UV detection in plasma from a 41 years old man who presented with a severe deficiency of vitamin K-dependent clotting factors of unknown aetiology. A longitudinal toxicological study of the consequent coagulopathy is described. 2. Plasma concentrations of difenacoum declined from 0.97 to 0.11 mgl-1 in 47 days with a terminal half life of 11.7 days. Rifampacin (300 mg bd) had no apparent effect on the terminal half life of the drug. Subsequently plasma concentrations of difenacoum and descarboxyprothrombin (DCP) unexpectedly increased. 3. Seven months after exposure clotting times were prolonged. The patient continued to have episodes of epistaxis, haematoma, purpurae and bruising and he required frequent treatment with Fresh Frozen Plasma in additional to oral phylloquinone (200 mg day-1). 4. Intermittent and unexpected increases in plasma concentrations of difenacoum and descarboxypro-thrombin suggested that covert, repeated ingestion of the anticoagulant was the most likely cause of the poisoning. The measurement of low concentrations of plasma phylloquinone except following supervised ingestion of the vitamin indicated that as an outpatient, the subject was not compliant with treatment despite his protestations to the contrary. He continued to deny this even when confronted by laboratory findings and at no time did he ever admit to self-poisoning.