Deletion analysis of yeast Sec65p reveals a central domain that is sufficient for function in vivo

The Saccharomyces cerevisiae SEC65 gene encodes a 32 kDa subunit of yeast signal recognition particle that is homologous to human SRP19. Sequence comparisons suggest that the yeast protein comprises three distinct domains. The central domain (residues 98-171) exhibits substantial sequence similarity to the 144 residue SRP19. In contrast, the N-terminal and C-terminal domains (residues 1-97 and 172-273 respectively) share no similarity to SRP19, with the exception of a cluster of positively charged residues at the extreme C-terminus of both proteins. Here, we report the cloning of a Sec65p homologue from the yeast Candida albicans that shares the same extended domain structure as its S. cerevisiae counterpart. This conservation of sequence is reflected at the functional level, as the C. albicans gene can complement the conditional lethal sec65-1 mutation in S. cerevisiae. In order to examine the role of the N- and C- terminal domains in Sec65p function, we have engineered truncation mutants of S. cerevisiae SEC65 and tested these for complementing activity in vivo and for SRP integrity in vitro. These studies indicate that a minimal Sec65p comprising residues 76-209, which includes the entire central SRP19-like domain, is sufficient for SRP function in yeast.

On memories of childhood abuse: a phenomenological study

OBJECTIVE

To explore the phenomenon of memories and reported recovered memories of childhood abuse, and to examine ways in which clients and therapists assess the veridicality of such memories.

METHOD

Qualitative methodology utilizing phenomenological inquiry. Within the context of a wider study exploring perceptions of helpful and unhelpful factors in the therapeutic process, a sub-sample of 36 in-depth interviews with clients, therapists, and therapists who considered themselves to have been abused as children included a focus on abuse-memory experiences. Data were analyzed according to Grounded Theory principles.

RESULTS

Participants described six types of abuse-memory experiences. The most frequently reported type was where abuse was known about but kept "out of mind." The six types can be collapsed into three main categories: (1) continual knowledge of abuse (69.5%); (2) unexpected abuse-memories recovered from a prior state of partial knowledge of abuse (16.5%); and (3) abuse-memories recovered from a prior state of no knowledge of abuse (30%). Independent corroboration of recovered memories was rare; and criteria which were reportedly used to assess the veridicality of such memories were problematic when viewed in the light of cognitive psychology research on memory processes.

CONCLUSION

It seems that most people who were abused as children have always had continual knowledge of this, although it is often only much later than many connect problems in adult life with the consequences of such abuse. People also experience the recovery of memories of abuse about which they were previously unaware. There is a danger that the specific controversy surrounding "false memories" may become over-generalized contributing to increased public scepticism about the prevalence and negative impact of child abuse, and the potential effectiveness of appropriate therapeutic services.

Quantitative and qualitative performance of stroke versus normal elderly on six clock drawing systems

The utility of the Clock Drawing Test (CDT) in localizing lesions has not been thoroughly examined to date. In the present study, six scoring systems (Freedman et al., 1994; Ishiai, Sugishita, Ichikawa, Gono, & Watabiki, 1993; Mendez, Ala, & Underwood, 1992; Rouleau, Salmon, Butters, Kennedy, & McGuife, 1992; Sunderland et al., 1989; Tuokko, Hadjistavropoulos, Miller, & Beattie, 1992; Watson, Arfken, & Birge, 1993; Wolf-Klein, Silverstone, Levy, & Brod, 1989) were used to assess clock drawings by 76 stroke patients and 71 normal controls. Significant differences were found between normals and stroke patients on all scoring systems for both quantitative and qualitative features of the CDT. Quantitative indices were not helpful in differentiating between various stroke groups (left versus right versus bilateral stroke; cortical versus subcortical stroke; anterior versus posterior stroke). Qualitative features were helpful in lateralizing lesion site and differentiating subcortical from cortical groups. Correlational analyses revealed that CDT performance was related to visuospatial processing and measures commonly used in cognitive screening.

Dialogue. Industry consolidation: what's at stake for consumers and purchasers?

The behavioral healthcare field has undergone massive consolidation, especially in the last year. Health plans, hospital systems, and community-based organizations have all been affected. Economists argue that consolidation is a logical consequence of the current, competitive healthcare market. But consumers and purchasers wonder if the mergers and acquisitions will benefit them. Efficient markets are supposed to stimulate competition in ways that reward purchasers and consumers of services. When prices go down and quality improves as a result of competitive market forces, then the market has functioned properly and has served its purpose. Behavioral healthcare, however, is an essential human service, not a commodity. And the consumers and purchasers of healthcare are typically not the same person or entity, which also makes the healthcare market different from the markets for cars, computers, food, or any other type of consumer product. More than 100 million Americans now receive managed behavioral health benefits from only three companies. With such intense power concentrated in the hands of such a small number of providers, the time has come to evaluate the impact of the consolidation trend. In the following dialogue article, leaders, representing different interest groups review the benefits and risks of massive industry consolidation, and propose solutions to the critical challenges that it raises.

Treatment of intracranial ependymoma by surgery alone

OBJECTIVE

This study aimed to determine the safety of deferring radiotherapy in pediatric intracranial ependymoma following a radiographically confirmed gross total resection in patients with localized disease.

METHODS

Children over age 3 were recruited prospectively from 1990 to 1997, following a surgical impression and radiologic confirmation of a gross total resection of an intracranial ependymoma.

RESULTS

10/32 cases of intracranial ependymomas were both eligible and gave consent. 7 remain free of disease without further intervention. 3 recurred, 2 were salvaged with surgery and radiotherapy, none died.

CONCLUSIONS

Deferral of radiotherapy following gross total resection alone is a safe option in supratentorial ependymomas. The pattern of recurrence is usually local and patients may be salvaged with additional surgery with or without radiotherapy.

Low dihydrotestosterone and weight loss in the AIDS wasting syndrome

24 consecutive AIDS patients with wasting, and who had never received anabolic therapies, were evaluated to determine their profile of sex hormones and whether transformation of testosterone (T) to the nuclear androgen, dihydrotestosterone (DHT), was impaired. Eleven (46%) patients had normal testosterone and DHT (group I), 10 (42%) had normal testosterone but low DHT (group II), and 3 (12%) had low testosterone and low DHT (group III). Age, prior opportunistic complications, symptoms, serum albumin, hemoglobin levels, and CD4 lymphocyte counts were similar in the groups. DHT was significantly lower (22.2 +/- 6.8 microg/dl) in group II compared with group I (50.8 +/- 15.3 microg/dl). The ratio of T/DHT, a measure of the conversion of testosterone to DHT, in group I was 15.1 +/- 3.5, which was within the range for eugonadal young men. In group II, the ratio was 22.3 +/- 1.5, indicating a defect in generation of DHT. Patients in group II had lost 9.2 +/- 3.5 kg compared with 5.6 +/- 2.6 kg in group I (p = .015). Thus, a syndrome of low DHT with normal testosterone was associated with significantly greater weight loss than in patients with normal testosterone and DHT. Further studies are needed to clarify whether low DHT is a result of AIDS wasting or is causally related to weight loss and whether androgen therapy in the form of DHT could reverse some of the metabolic changes associated with AIDS wasting.

Blister fluid for the diagnosis of subepidermal immunobullous diseases: a comparative study of basement membrane zone autoantibodies detected in blister fluid and serum

The subepidermal immunobullous diseases bullous pemphigoid (BP), cicatricial pemphigoid (CP), pemphigoid gestationis (PG) and linear IgA disease (LAD) are characterized by circulating and in vivo deposition of antibodies to antigens in the cutaneous basement membrane zone (BMZ). Indirect immunofluorescence (IMF) of serum is a routine diagnostic test to detect circulating BMZ antibodies in these diseases. We have compared the titres of IgG and IgA and their subclasses, also of IgM and IgE BMZ antibodies in serum and aspirated blister fluid in 35 adult patients with subepidermal immunobullous diseases: BP (n = 30), PG (n = 2), CP (n = 1), and LAD (n = 2), by indirect IMF on intact and salt-split skin. The antibody titre in blister fluid was the same or one dilution less than serum in most cases and there was no significant difference between these results (P > 0.05). IgG1 and IgG4 were the predominant subclasses in both blister fluid and serum in BP. Indirect IMF of serum and blister fluid was also carried out on trypsinized epidermal cells in a subgroup of patients with BP (n = 19). Typical polar fluorescence was obtained in all 14 cases which had positive indirect IMF on intact and split skin. Our findings demonstrate that blister fluid can be used as an alternative to serum for indirect IMF in subepidermal immunobullous diseases. This avoids the need for venesection and has a practical application in children and those with poor venous access.

The association of HLA-DQ7 with bullous pemphigoid is restricted to men

This study examines in detail the HLA associations of 74 patients (40 women and 34 men) with bullous pemphigoid (BP) and compares their immunogenetic profile with that of 604 unrelated control subjects (238 women and 366 men). Correlations were sought between HLA antigens and the various BP disease parameters investigated. The presence of milia was the only clinical or laboratory finding which was linked with a specific HLA antigen, HLA-DQ6, in both men and women with BP (P < 0.01). BP has previously been linked with the HLA-DQ7 antigen and this association was confirmed in 39 of our patients (14 women and 25 men). Twelve of these patients (four women and eight men) were homozygous for HLA-DQ7. The association of HLA-DQ7 with BP was gender-restricted and only significant for men (P < 0.01). No equivalent HLA disease susceptibility risk factor could be identified for our female BP patients. This difference in HLA association between men and women with BP has not been reported previously, and its significance for disease pathogenesis is not known. No specific link could be found between HLA-DQ7 and BP for any of the clinical, immunofluorescence, western blotting, treatment or prognostic disease factors studied.

What determines competence within a general practice consultation? Assessment of consultation skills using simulated surgeries

A method for assessing the consultation skills required in general practice using patient simulators within a simulated surgery has been developed in Leicester, aimed at registrars coming to the end of their three-year training programme. This paper addresses the issues of validity, describing the technique as it has evolved over the past three years, and paying particular attention to ways in which the consultation was made to feel 'real' for candidates. As well as testing clinical issues during consultations, simulated surgery incorporates the views of the patient into the assessment process. Feedback from registrars has been positive and the method presents an alternative to video-recording the consultation for the purpose of assessment.

Simulated surgery in the summative assessment of general practice training: results of a trial in the Trent and Yorkshire regions

BACKGROUND

General practice registrars are now required to undertake a summative assessment of their consulting skills. Simulated surgeries have been developed as an alternative to the existing method of assessing video-recorded consultations.

AIM

To evaluate the simulated surgery assessment method, developed in the General Practice Postgraduate Education Department in Leicester, for use in assessing general practice consultation skills.

METHOD

General practice registrars in Leicester performed two eight-patient simulated surgeries separated by four weeks. Assessment outcomes were compared to demonstrate the consistency of the method. Pilot surgeries in Yorkshire were videotaped, and then rated by video-raters trained for summative assessment.

RESULTS

The method consistently identified those registrars who were competent and those who were not yet competent in consulting skills. It proved acceptable to candidate doctors and has fewer resource requirements for both examiners and candidates than other consulting skills assessment methods.

CONCLUSION

The method developed in Leicester and successfully transferred to Yorkshire is feasible on a large scale, and offers an acceptable alternative to other consulting skills assessment methods. In this study it consistently identified competent from incompetent candidate doctors.

Reliability of photographic analysis in determining change in scar appearance

Photographs frequently are used to document change in the management of hypertrophic scars. The purpose of this study was to design a scale for the analysis of photographs of hypertrophic scars and to test its reliability. The subjects were four occupational and physical therapists, (two novices and two experts), in scar management. Existing scales were modified to produce a new scale. The subjects twice rated four slides from each of ten patients' scars, in random order. They used a Latin Square design. Interrater and test-retest reliabilities were calculated using a weighted kappa statistic. The newly developed scale demonstrated interrater reliability, which ranged between 0.66 and 0.90 for all items. The test-retest reliability ranged between 0.73 and 0.89 for all items. The new scale had substantial reliability (using a single rater) and was at least as reliable when used by novice therapists. This indicated that training had no effect.

Use of the esophageal detector device in a newborn-piglet model

STUDY OBJECTIVE

To determine the accuracy of the esophageal detector device (EDD) in predicting correct endotracheal tube (ETT) placement in a newborn-piglet model.

METHODS

We used an EDD, comprising a 5-, 10- or 20-mL syringe attached to 4-mm tubing fitted to a 15-mm ETT adapter, to aspirate gas from cuffed or uncuffed ETTs placed in the trachea or esophagus of each newborn piglet. During aspiration, we noted any resistance encountered while pulling back the plunger of the syringe and recorded the total volume of gas aspirated into the syringe. A positive test, signifying tracheal ETT placement, was defined as the ability to freely aspirate gas without resistance and the aspiration of enough gas to fill the entire volume of the syringe. A negative test, signifying esophageal ETT placement, was defined as resistance encountered during the aspiration of gas into the syringe and rebound of the syringe plunger, leading to aspiration of a volume of gas less than the total volume of the syringe.

RESULTS

We conducted 444 trials (222 for uncuffed ETTs, 222 for cuffed ETTs). ETT size ranged from 3.0 to 4.5 mm. For cuffed ETTs, the 5-mL syringe had a sensitivity of 100% and a specificity of 5%, the 10-mL syringe had a sensitivity of 95% and a specificity of 16%, and the 20-mL syringe had a sensitivity of 86% and a specificity of 97%. For uncuffed ETTs, the 5-mL syringe had a sensitivity of 100% and a specificity of 5%, the 10-mL syringe had a sensitivity of 97% and a specificity of 24%, and the 20-mL syringe had a sensitivity of 81% and a specificity of 100%.

CONCLUSION

No syringe had 100% sensitivity and specificity in correctly predicting ETT placement. The 20-mL syringe had the highest combination of sensitivity and specificity. Further studies are warranted to determine whether the EDD using a 20-mL syringe would aid in the prediction of correct ETT placement in the pediatric population.

Conduction aphasia in a 3-year-old with a left posterior cortical/subcortical abscess

A 3-year-old, right-handed girl developed a conduction-type aphasia following a second generalized seizure in the setting of a developing abscess involving left subcortical and cortical angular gyrus and arcuate fasciculus, and the posterior corpus callosum. The language disorder was fluent, characterized by age appropriate mean length of utterance and syntax, but with markedly reduced spontaneity of output, rapid rate of speech and mild dysarthria. Comprehension was relatively, but not completely spared. Naming, repetition, and reading (letters) were initially markedly impaired. Improvements in naming and repetition were associated with both literal and semantic paraphasias. Writing skills in the form of drawing were spared, but a mild apraxia to verbal command and imitation was initially present. Despite her young age, this child's fluent conduction aphasia and lesion localization were adult-like. Multimodal memory difficulties appeared to underlie what is best described as conduction aphasia.

Patterns of recurrence in brain stem gliomas: evidence for craniospinal dissemination

PURPOSE

The 3-year survival rate of pediatric patients with infiltrating brain stem gliomas (BSG) is < 10%. Treatment involves local field radiation, and local failure has been the hallmark of recurrence. With therapeutic advances and improved radiographic monitoring, perceived and actual patterns of failure may change. We report patterns of recurrence in a group of patients with close follow-up, treated on an institutional protocol incorporating hyperfractionated involved-field radiation therapy and concomitant carboplatin, who have been uniformly staged and treated and have undergone MRI surveillance.

METHODS AND MATERIALS

From 1990-1995, 18 pediatric patients with BSG were treated on a Phase I-II trial of concurrent carboplatin and hyperfractionated radiotherapy. Eight had surgical procedures to document histology. Nine had hydrocephalus prior to death. All had pretreatment brain and spine MRIs, with and without gadolinium, that showed no other evidence of disease. Treatment consisted of 72.00 Gy involved-field hyperfractionated radiation therapy and dose-escalating concomitant carboplatin.

RESULTS

Fifteen children have had progression of disease (median PFS = 9 months); and 13 have died (median OS = 14 months). Fourteen of the 15 children with progression had local failures, 8 of whom had evidence of noncontiguous spinal (4) or intracranial (7) disease documented by MRI or autopsy. One child with local control developed an intracranial metastasis. None had clinical manifestations of leptomeningeal disease.

CONCLUSION

Leptomeningeal dissemination occurred within 1 month of local progression in nearly 30% of our patients and, overall, occurred in 50% prior to death. This high incidence may reflect close MRI surveillance or a changing pattern of recurrence. Because the majority of leptomeningeal disease occurs in the setting of local progression, treatment efforts must be directed primarily toward local control. However, management of leptomeningeal dissemination at recurrence is of increasing concern.

Drug-induced linear IgA disease with antibodies to collagen VII

Linear IgA disease (LAD) is characterized by circulating and tissue-bound IgA antibodies against heterogeneous antigens in the cutaneous basement membrane zone. In most cases the cause is unknown, but a minority of cases has been drug induced. We report a 76-year-old man who developed an acute blistering eruption following high-dose penicillin treatment for pneumococcal septicaemia. Indirect immunofluorescence demonstrated dermal binding IgA antibodies, and Western blotting of serum showed reactivity with a 250 kDa dermal antigen corresponding to collagen VII of anchoring fibrils. Indirect immunoelectron microscopy showed antibody labelling in the lamina densa and sublamina densa zone. This is one of the few cases of drug-induced LAD in which the target antigen profile has been characterized, and the first in which the antigen has been shown to correspond to collagen VII.

Plasma concentration of soluble intercellular adhesion molecule 1 and risks of future myocardial infarction in apparently healthy men

BACKGROUND

The intercellular adhesion molecule ICAM-1 mediates adhesion and transmigration of leucocytes to the vascular endothelial wall, a step proposed to be critical in the initiation and progression of atherosclerosis. Whether concentrations of soluble ICAM-1 (sICAM-1) are raised in apparently healthy individuals who later suffer acute myocardial infarction is unknown.

METHODS

We obtained baseline plasma samples from a prospective cohort of 14,916 healthy men enrolled in the Physicians' Health Study. With a nested case-control design, we measured sICAM-1 concentrations for 474 participants who developed a first myocardial infarction, and 474 controls (participants who remained healthy throughout the 9-year follow-up). Cases were matched to controls according to age and smoking status at the time of myocardial infarction.

FINDINGS

We found a significant association between increasing concentration of sICAM-1 and risk of future myocardial infarction (p = 0.003), especially among participants with baseline sICAM-1 concentrations in the highest quartile (> 260 ng/mL; relative risk 1.6 [95% Cl 1.1-2.4], p = 0.02). This association was present overall as well as among non-smokers, and persisted after control for lipid and non-lipid risk factors. In multivariate analyses, the risk of future myocardial infarction was 80% higher for participants with baseline sICAM-1 concentrations in the highest quartile (relative risk 1.8 [1.1-2.8], p = 0.02). Similar risk estimates were seen among non-smokers. We found slight but significant correlations between sICAM-1 and fibrinogen, high-density-lipoprotein cholesterol, homocysteine, triglycerides, tissue-type plasminogen-activator antigen, and C-relative protein, but adjustment for these altered the risk little. The risk of myocardial infarction associated with raised concentrations of sICAM-1 seemed to increase with length of follow-up.

INTERPRETATION

Our data support the hypothesis that cellular mediators of inflammation have a role in atherogenesis and provide a clinical basis to consider antiadhesion therapies as a novel means of cardiovascular disease prevention.