The under-reporting of skin disease in association with squamous cell carcinoma of the vulva

Histology sections from 61 cases of squamous cell carcinoma (SCC) of the vulva presenting after 1988 were reviewed for evidence of associated epithelial abnormality. Of the 50 patients with epithelium adjacent to the tumour, 24 had histological evidence of lichen sclerosus (LS), 20 of severe vulvar intraepithelial neoplasia (VIN 3), 22 of human papilloma virus (HPV) infection and three of lichen planus (LP). The clinical records and the original histology report were also subsequently reviewed and with the exception of VIN 3, these disorders were poorly reported by both clinicians and pathologists. Lichen sclerosus was diagnosed clinically in only two of the 36 hospital records available for inspection. Old terminology was used to describe some patients with epithelial disease (erythroleucoplakia in one patient with LS, leucoplakia in two patients with LS and one with LP). This study demonstrates the need to adopt standard nomenclature and increase the awareness of epithelial disease associated with SCC of the vulva among clinicians and pathologists.

An essential component of the decapping enzyme required for normal rates of mRNA turnover

A major pathway of messenger RNA degradation in eukaryotic cells is initiated by shortening of the poly(A) tail, which, at least in yeast, triggers a decapping reaction, thereby exposing the mRNA to 5' --> 3' degradation. Decapping is the key step in this decay pathway because the transcript body is rapidly degraded following decapping. Accordingly, decapping is the site of numerous controls, including inhibition of decapping by the poly(A) tail and modulation of mRNA decapping rate by specific sequences. Moreover, a specialized decay pathway that degrades aberrant transcripts triggers rapid mRNA decapping independently of poly(A)-tail shortening. We have identified a yeast gene, termed DCP1, that encodes the decapping enzyme, or an essential component of a decapping complex. The protein Dcp1 is required for the normal decay of many unstable and stable yeast mRNAs, as well as mRNAs that are decapped independently of deadenylation. These results indicate that mRNA-specific rates of decapping, and thus decay, will result from differences in the interaction of the DCP1 decapping enzyme with individual transcripts.

The effect of concentration on the structure of alpha-crystallin

Several models have been proposed for arrangement of the subunits in alpha-crystallin. These include the contrasting proposals that subunits are arranged in three layers and that subunits assemble into micelle-like structures. The validity of the micelle model was investigated by examining the effects of variations in protein concentration on the surface tension, conductivity, molecular weight and conformation of alpha-crystallin. The data were compared with those obtained for bovine serum albumin (BSA) and sodium dodecyl sulphate (SDS). Measurements of surface tension were conducted in the range, 10 micrograms ml-1 to 130 mg ml-1, in low and high ionic strength buffers. An apparent point of inflection, independent of ionic strength, was seen in alpha-crystallin's surface tension at around 1.9 mg ml-1 (95 microM). The surface tension did not plateau beyond this point, as is the case with surfactants, but continued to decrease up to 130 mg ml-1. BSA exhibited similar surface tension properties with an apparent inflection at 0.9 mg ml-1 (13 microM). The conductivity of alpha-crystallin and BSA solutions increased smoothly with no sign of any transition up to 96 mg ml-1 and 60 mg ml-1, respectively. In contrast, SDS showed a clear transition in this property at the concentration corresponding to its CMC. The aggregation state of the alpha-crystallin aggregates was examined by comparing molecular masses and Stokes radii. The size of the protein remained uniform over a wide concentration range and was unaffected by variations in ionic strength. Protein conformation, which was monitored by examining the microenvironment of tryptophan residues, was also found to be independent of protein concentration. It is concluded that over the concentration range that was investigated, alpha-crystallin does not exhibit any of the properties associated with classical micelles formed from small amphiphilic molecules.

The evaluation of diagnostic and prognostic criteria and the terminology of thin cutaneous malignant melanoma by the CRC Melanoma Pathology Panel

Sections from 95 skin lesions excised at pigmented lesion clinics in England and Scotland were studied by eight histopathologists in order to evaluate consistency in the use of histopathological terms for features of diagnostic and prognostic importance for cutaneous malignant melanoma. The level of agreement (kappa) amongst the panel improved after discussion and re-definement of criteria for several features. These included, architectural and nuclear atypia, pagetoid infiltration and radial and vertical growth phases. A high level of agreement was achieved for an overall benign or malignant diagnosis (kappa = 0.77) but use of more specific terms such as benign naevi with atypia and melanoma < or = 0.76 mm thickness, was associated with only an intermediate level of agreement. Of the original diagnosis of melanoma, 17% were re-classified by the panel as benign with atypia and 2% reported to be benign were judged to be melanoma. This reflected the high proportion of borderline lesions in the study. The use of standardized diagnostic criteria with precise definitions has been shown to improve consistency in diagnosis and it is recommended for general application. From this should emanate more reliable incidence figures for thin melanoma, and improved understanding of the nature of these early lesions, to the benefit of patient and clinician alike. The poor concordance in distinguishing severe dysplasia in the junctional component of melanocyte proliferations from melanoma in situ and superficial dermal invasion improved only modestly despite intensive efforts. Since melanoma in situ and severe dysplasia cannot be distinguished by objective measurements and since their clinical management is the same, the panel suggests that attempts to separate them in diagnostic reports should be discontinued and they could both be referred to as melanocytic intraepidermal neoplasia (MIN). If it becomes accepted that dermal invasion without a vertical growth component can also be managed identically to MIN, then this invasive radial phase may be appropriately referred to as microinvasion and linked to MIN for the purposes of clinical management.

Morphometric evidence that epithelial basement membrane breaks are a feature of both squamous and basal cell carcinomas of the skin

There have been reports that squamous cell carcinomas (SCC) and basal cell carcinomas (BCC) are surrounded by continuous epithelial basement membranes (EBMs). This argues against the hypothesis that EBM breaks are required for tumour invasion. We have used morphometric techniques to re-examine the evidence for SCCs and BCCs as objectively as possible. We assessed sections stained for type-IV collagen from 12 SCCs, 14 keratoacanthomas (KAs), 9 morphoeic BCCs, 10 nodular BCCs and 7 superficial multifocal BCCs. In the centre of these tumours, the EBM was generally more continuous than at the periphery, and this difference was statistically significant for SCCs, KAs and morphoeic BCCs (p < 0.01 in all). By considering central and peripheral tumour regions separately, a significant difference was seen between SCCs and the difficult to distinguish benign tumour KA. In the centre of the KAs, EBM was significantly more continuous than than in SCCs (p = 0.0029), which may suggest new ways of distinguishing these lesions. All of the SCCs and morphoeic BCCs examined showed clear evidence of EBM breaks, but some nodular BCCs did not. As nodular BCCs show an expansile growth pattern without typical histological features of tumour invasion, we suggest that these tumours may be at a pre-malignant stage. In general, our findings are consistent with the hypothesis that EBM breaks are required for tumour invasion.

A sheet-like form of alpha-crystallin

Complexes containing alpha-crystallin were isolated from crosslinked lens extract using an affinity column constructed with monoclonal antibodies specific for alpha-crystallin. The affinity-purified protein was compared with alpha-crystallins before and after crosslinking. Electron microscopy revealed sheet-like structures in the cross-linked protein from the lens extract compared with spherical structures for the others. Studies on the amino acid composition, tryptophan microenvironments and the interaction with a monoclonal antibody revealed that the complexes consist almost entirely of alpha-crystallin. These results indicate that under certain conditions, alpha-crystallin subunits can adopt a sheet-like form.

Abnormal topography of EEG microstates in Gilles de la Tourette syndrome

Quantitative analysis of scalp EEGs was performed on 13 patients with Gilles de la Tourette syndrome (GTS) and 25 matched controls. The analysis method was adaptive segmentation, which describes the topography and sequence of brain electric fields in continuous EEG. The GTS patients showed an abnormal increase in fields with a right-frontal/left-posterior configuration. The GTS patient's EEGs did not differ from normal controls in the average duration of the brain electric microstates, field stability and EEG carrier frequency. To find out whether the abnormal activity is similar to movement-related activity a simple and a complex motor task were performed. Both tasks led to distinct changes of brain electric activity, but not to an increase in right-frontal-/left-posterior-oriented patterns. Motor-related activity was contrasted with two auditory tasks. We conclude that GTS patient's EEG show abnormal topographic patterns of brain electric activity. Unlike other psychiatric disorders, the temporal descriptors of the EEG aspects are unaffected. The abnormal EEG patterns in GTS patients are not similar to those elicited by simple or complex movements; thus, the presence of abnormally facilitated, near-threshold motor activity in GTS patients seems not a likely explanation.

Dementia and depression: Co-distribution and risk factors in a geriatric in- and outpatient sample

The results of a cross-sectional study on N = 212 elderly in- and outpatients are presented including sociodemographic data, physical findings, CAT-scan and EEG, as well as psychological tests for cognitive performance and affective symptoms. Forty-one percent of the patients showed mild and 13% severe cognitive deficits. Depression was diagnosed in 23% of the severely impaired and in 16% of the cognitively mildly impaired or unimpaired patients. Statistical analysis revealed that increasing age, female sex and low premorbid intellectual level were significantly associated with loss of cognitive function. Dementia and depression were not significantly associated with each other. The only risk factor for depression was a history of affective illness, but not cognitive deficits or social situation. CAT-scan and EEG were abnormal in 50% of the patients; however, this did not correlate with cognitive impairment or the presence of depression. From this study it is concluded that depression and dementia coincide frequently in elderly patients, but that they are associated with different risk factors It is suggested that dementia and depression are treated as two distinct disease entities.

The effectiveness of putative anti-cataract agents in the prevention of protein glycation

BACKGROUND

Recent data have favored non-enzymatic glycation as a likely mechanism in diabetic cataract formation. The advanced glycation end products (AGEs) that are formed lead to opacification of the lens by disrupting the short-range order between the proteins. Attempts to decrease AGE formation has led to the use of various anti-glycating agents. Their efficacy, however, has been questionable.

METHODS

The extent of AGE formation was monitored in fetal bovine eyes using non-tryptophan fluorescence. The amount of carbohydrate bound to the proteins was measured after reduction with radio-labelled sodium borohydride.

RESULTS

While the addition of glucose, glucose-6-phosphate or fructose increased the levels of glycation by only 25 percent and the levels of AGEs by 40 percent, glyceraldehyde resulted in a 70 percent increase in glycation and showed extensive AGE formation (an increase of over 6600 percent when compared to the unglycated protein). The anti-glycating agents aspirin and ibuprofen were unable to significantly decrease the extent of bound metabolite or reduce the amount of AGE formed. In contrast, penicillamine and aminoguanidine were more effective in reducing the levels of AGEs, even though the levels of bound metabolite appeared unchanged.

CONCLUSIONS

Triose phosphates are likely to be the major metabolic intermediates that result in AGE formation. The anti-glycating agents, whereas penicillamine and aminoguanidine-which react with the Amadori-derived fragmentation products-significantly decreased levels of AGEs.

Acute graft-versus-host disease with unusual cutaneous intracellular vacuolation in an infant with severe combined immunodeficiency

We report an infant with severe combined immunodeficiency (SCID) who had cutaneous manifestations of acute graft-versus-host disease (GVHD) due to maternofetal lymphocyte engraftment. Histologic and ultrastructural examinations of the skin revealed intracellular vacuoles resembling lipid droplets in the epidermis and dermis, which is not a recognized feature of acute GVHD or SCID.

[Diagnosis and management of neurotic occupational disorders (before pension application)]

This paper summarizes how neurotic disorders affect working capability, with an emphasis on neurotic working disorders. According to official statistics neurotic disorders account for 5.5% of all disability pensions, but they figure less often as diagnoses in medical certificates issued prior to invalidation. The true impact of neurotic disorders may only be guessed, since the diagnosis is easy to miss and only reluctantly proffered when suspected. In contrast to other neurotic disorder afflicting working behaviour, the neurotic working disorder is thematically centered within the sphere of work and profession itself. The disorder is often treated inadequately and belatedly. Typical somatic complaints clusters, characteristic neurotic conflicts and personality traits often encountered with neurotic working disorder are outlined. Diagnosis requires the taking of a psychobiographic history and some knowledge of psycho- and soziotherapy. There are many options for therapy, and there are a few studies evaluating their efficacy. In order to install treatment early, a routine checkup by a psychotherapist is suggested for all patients exceeding a certain number of days off work per year.

Do schizophrenics not differentiate between perception and imagination? an EEG study using dimensional analysis

The electroencephalograms (EEGs) of 18 chronic schizophrenic patients and 16 controls were compared during three experimental conditions: simple mental arithmetic, the perception of a moving double pendulum, and the imagination of it. An elevated dimensional complexity of the EEG of schizophrenic patients during perception as compared to normals and a failure to increase dimensional complexity during mental imagery was found. No differences were found during mental arithmetic. It is concluded that the brains of schizophrenics operate during perception in a functional state that is characterised by increased and apparently unnecessary complexity.

5'-exonuclease-2 of Saccharomyces cerevisiae. Purification and features of ribonuclease activity with comparison to 5'-exonuclease-1

5'-Exonuclease-2 has been purified 17,000-fold from whole cell extracts of Saccharomyces cerevisiae. A 116-kDa polypeptide parallels the enzyme activity when the purified protein is examined by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. Amino-terminal sequencing of the 116-kDa protein shows that the sequence agrees with that encoded by the HKE1 gene, previously reported to encode exonuclease-2. A 45-kDa polypeptide also parallels the enzyme activity upon purification, and Sephacryl S-200 molecular sieve chromatography of the purified enzyme shows a parallel elution of most of the 116- and 45-kDa polypeptides, suggesting a close association of the two. Enzyme instability has precluded a more detailed analysis of their associative properties. The enzyme hydrolyzes RNA substrates to 5'-mononucleotides in a processive manner. Measurements of its substrate specificity and mode of action are compared with 5'-exonuclease-1. Restriction cut single-stranded T7 DNA is hydrolyzed at approximately 5-7% of the rate of 18 S rRNA of yeast by both enzymes. That 5'-exonuclease-2 hydrolyzes in a processive manner and lacks endonuclease activity is shown by the finding that [5'-32P]GMP is the only product of its hydrolysis of [alpha-32P]GTP-labeled synthetic RNAs. That 5'-exonuclease-2 hydrolyzes by a 5'-->3' mode is shown by: 1) its poor hydrolysis of both 5'-capped and triphosphate-ended RNA substrates; 2) the products of its hydrolysis of [5'-32P,3H](pA)4; and 3) the accumulation of 3'-stall fragments when a strong artificial RNA secondary structure is present in synthetic RNAs. 5'-Exonuclease-1 hydrolyzes the synthetic RNAs and (pA)4 in an identical manner.

A germline substitution in the human MSH2 gene is associated with high-grade dysplasia and cancer in ulcerative colitis

BACKGROUND & AIMS

The DNA mismatch repair gene human MSH2 shows a germline mutation in certain family members with hereditary nonpolyposis colorectal cancer. There is an increased risk of colorectal cancer in patients with ulcerative colitis (UC) with extensive disease of > 8 years' duration; however, specific constitutional predisposing genetic abnormalities have not yet been identified.

METHODS

A germline human MSH2 abnormality was sought in patients with UC with high-grade dysplasia or carcinoma.

RESULTS

After direct sequencing of exon 13 and flanking regions of human MSH2, a germline T to C substitution was shown at the -6 intronic splice acceptor site of exon 13. This substitution was found in 14 of 53 patients with UC with high-grade dysplasia or carcinoma (26%) compared with 4 of 36 high-risk patients with UC without dysplasia or cancer (11%) (P < or = 0.04) and in 7 of 80 healthy adult blood donors (9%) (P < or = 0.003). The patients with UC who had the substitution were three times more likely to develop neoplasia than patients with UC who did not carry it.

CONCLUSIONS

An intronic splice-site substitution in the human MSH2 gene is present in the general population but may predispose to cancer in the setting of UC.

Controlled heroin availability in Australia? How and to what end?

The general public, police, service providers, and users/ex-users were asked their views about options for trial design and trial outcomes with regard to a proposal for experimental controlled heroin availability. There was substantial agreement between the samples on issues concerning trial design. In general, the samples from the community, service providers and users/ex-users were more likely to report that a trial would result in positive outcomes, whereas the police sample was more likely to report that a trial would result in negative outcomes. This study illustrates the value of systematic consultation of key groups in exploring the options for change, raising potential difficulties, and highlighting different interests.

13C-NMR off-resonance rotating frame spin-lattice relaxation studies of bovine lens gamma-crystallin self association: effect of 'macromolecular crowding'

The NMR technique of 13C off-resonance rotating frame spin-lattice relaxation, which provides an accurate assessment of the effective rotational correlation time (tau 0, eff) for macromolecular rotational diffusion, was applied to the study of gamma-crystallin association as a function of protein concentration and temperature. Values of the effective rotational correlation time for gamma-crystallin rotational diffusion were obtained at moderate to high protein concentrations (80-350 mg/ml) and at temperatures above, and below, the cold cataract phase transition temperature. With increasing concentration gamma-crystallin was observed to increasingly associate as reflected by larger values of tau 0, eff Decreasing temperature in the range of 35 to 22 degrees C was found to result in no change in the temperature corrected value of tau 0, eff at a gamma-crystallin concentration of 80 mg/ml, whereas at temperatures of 18 degrees C or below, this parameter was approx. twofold larger, suggesting the occurrence of a well defined phase transition, which correlated well with the cold cataract phase transition temperature. At higher protein concentrations, by contrast, tau 0, eff (temperature corrected) was found to increase by approx. 1.6- to 2-times in the temperature interval 35 degrees C to 22 degrees C, a result consistent with the dependence of the cold cataract phase transition temperature on gamma-crystallin concentration. Analysis of intensity ratio dispersion curves, using an assumed model of isodesmic association, permitted the estimation of the association constant characterizing the aggregation under particular conditions of concentration and temperature. The significant increase in the value of the association constant with moderate increases in protein concentration was rationalized by invoking the effect of 'macromolecular crowding'. The results obtained in this study suggest that in the intact lens, where high protein concentrations prevail, gamma-crystallin is unlikely to be found in the monomeric state, but more likely, as a significantly aggregated species, representing a broad molecular weight distribution.

'Quick and clean': authoritative health technology assessment for local health care contracting

Commissioners of health care require rapid, accurate and usable information on health technology effectiveness to help them to decide on the content of contracts. Despite major strides in the national initiatives in health technology assessment, such information is still in short supply at the local level. In 1991 the former Wessex region (now in the new South and West Region) established a mechanism which continues to provide carefully established recommendations on new technologies. Its features include: identification of locally important topics for evaluation by the purchasers and the providers; an evaluation team, working to a well-defined format in a service-led academic institute; an arbitration committee to deliver recommendations to purchasers on the basis of both the cost-utility of proposals and the quality of the evidence; and implicit obligations for purchasers to respond to strong recommendations.

Health technology assessment and gastroenterology

Too much clinical practice is based on unproved opinion. Health technology assessment (HTA) encourages critical review of the literature in a particular area, from which an objective assessment can be made so that clinical practice may be more scientifically based. Only a small number of centers undertake this type of work, usually at a national level. We have been able to set up a more local HTA system (the Wessex Development and Evaluation Committee) with links to clinicians and both providers and purchasers of health care within a region of 3 million people. All aspects of medicine may be reviewed and discussed by the committee; 3 examples from within the field of gastroenterology are summarized herein. Active participation of a university-based institute to provide the reviews is essential. A local HTA facility confers a number of advantages.