Mixed trends in heavy metal-enriched fugitive dust on National Park Service lands along the Red Dog Mine haul road, Alaska, 2006-2017

This study presents the status and trends of long-term monitoring of the elemental concentrations of zinc (Zn), lead (Pb), and cadmium (Cd) in Hylocomium splendens moss tissue in Cape Krusenstern National Monument (CAKR), Alaska, adjacent to the Red Dog Mine haul road. Spatial patterns of the deposition of these metals were re-assessed for the period from 2006-2017 following an identical study that assessed trends between 2001-2006. In contrast to the widespread and steep declines in Zn and Pb levels throughout most of the study area between 2001-2006, this study showed more mixed results for 2006-2017. At distances within 100 m of the haul road, only Pb decreased between 2006-2017. At distances between 100-5,000 m, however, both Zn and Cd decreased between 2006-2017, with high probabilities of decrease and percent decreases of 11-20% and 46-52% respectively. Lead did not decrease in any of the more distant areas. Following earlier work on lichen species richness in the study area, it appears that 2017 Zn levels are approaching those associated with "background" lichen species richness throughout a relatively large proportion of the study area at least 2,000 m from the haul road and several km from the port site. The findings in this study may be used to plan additional mitigation measures to reduce Zn deposition related to impacts on lichen communities.

Economic Evaluation of the Protecting Teeth @ 3 Randomized Controlled Trial

INTRODUCTION

An economic evaluation (EE) was conducted alongside a randomized controlled trial (the Protecting Teeth @ 3 Study [PT@3]), exploring the additional preventive value of fluoride varnish (FV) application at 6-monthly intervals in nursery schools compared to treatment as usual (TAU) in the same nurseries. TAU represented a multicomponent national child oral health improvement intervention, the Childsmile program, apart from nursery FV.

METHODS

The EE was a within-trial cost-utility analysis (CUA) comparing the FV and TAU groups. The CUA was conducted from a National Health Service perspective and followed relevant methods guidance. Within-trial costs included intervention costs and health care resource use costs. Health outcomes were expressed in quality-adjusted life years (QALYs) accrued over the 2-y follow-up period. The Child Health Utility 9 Dimensions questionnaire was used to obtain utility scores. National reference costs were used, a discount rate of 1.5% for public health interventions was adopted, multiple imputation methods for missing data were employed, sensitivity analyses were conducted, and incremental cost-utility ratios were calculated.

RESULTS

Data from 534 participants from the 2014-2015 PT@3 intake were used in the EE analyses, n = 265 (50%) in the FV arm and n = 269 (50%) in the TAU arm. Mean incremental cost per child in the FV arm was £68.37 (P = 0.382; 95% confidence interval [CI], -£18.04 to £143.82). Mean incremental QALY was -0.004 (P = 0.636; 95% CI, -0.016 to 0.007). The probability that the FV intervention was cost-effective at the UK £20,000 threshold was 11.3%.

CONCLUSION

The results indicate that applying FV in nurseries in addition to TAU (all other components of Childsmile, apart from nursery FV) would not be deemed cost-effective given current UK thresholds. In view of previously proven clinical effectiveness and economic worthiness of the universal nursery toothbrushing component of Childsmile, continuation of the additional, targeted nursery FV component in its pre-COVID-19 form should be reviewed given its low probability of cost-effectiveness.

KNOWLEDGE TRANSFER STATEMENT

The results of this study can be used by child oral health policy makers and dental public health professionals. They can form part of the evidence to inform the Scottish, UK, and international guidance on community-based child oral health promotion programs.

Lung Transplantation in COVID-19 Induced End Stage Lung Disease

Introduction

In a subset of patients COVID-19 induced lung injury progresses to irreversible lung damage and pulmonary fibrosis. Bilateral orthotopic lung transplant (BOLT) has been used as a rescue therapy in these patients. We describe four patients who were bridged to BOLT using venovenous extracorporeal membrane oxygenation (VV-ECMO).

Case Report

Between October 13, 2020 and February 14, 2021, four patients with SARS-CoV-2 infection underwent BOLT for end-stage pulmonary fibrosis demonstrated on computed tomography. Median age was 42 years and three were male. One patient had a prior history of undifferentiated interstitial lung disease managed with chronic steroids. Pre-transplant hospital course was complicated by right ventricular failure due to pulmonary hypertension in two patients and ventilator-associated pneumonia in one. One patient developed heparin-induced thrombocytopenia requiring anticoagulation with bivalirudin perioperatively. Three patients were non-ambulatory and bedridden for a median of 54 days prior to surgery. Timing of transplantation ranged from hospital day 26 - 68 with a median of 48 days. At the time of transplant, three patients were mechanically ventilated via tracheostomy, while all were on VV-ECMO a median of 27 (IQR 11 - 42) days. All patients underwent BOLT via clamshell exposure utilizing cardiopulmonary bypass (CPB) with aortic and right atrial cannulation. VV-ECMO was discontinued intraoperatively in all cases after initiating CPB. All patients required intraoperative blood transfusion with a median of 3 units. The three patients with tracheostomy prior to transplant were liberated from the ventilator a median of 9 days postoperatively and decannulated from their tracheostomy a median of 11 days postoperatively. Aside from one patient requiring short courses of hemodialysis, there were no significant postoperative complications. Patients were discharged a median of 17 (14 - 20) days following surgery. After a median follow-up of 226.5 (223 - 257.75) days, all four patients were alive with no supplemental oxygen requirement.

Summary

Pulmonary fibrosis secondary to COVID-19 pneumonia can be successfully treated with VV-ECMO and subsequent lung transplantation in select patients. Special consideration should be given to this patient population as they may not meet traditional listing requirements. We report a 100% oxygen-free survival rate at six months.

Concussion Recovery Phase Affects Vestibular and Oculomotor Symptom Provocation

Vestibular and oculomotor testing is emerging as a valuable assessment in sport-related concussion (SRC). However, their usefulness for tracking recovery and guiding return-to-play decisions remains unclear. Therefore the purpose of this study was to evaluate their clinical usefulness for tracking SRC recovery. Vestibular and oculomotor assessments were used to measure symptom provocation in an acute group (n=21) concussed≤10 days, prolonged symptoms group (n=10) concussed ≥16 days (median=84 days), healthy group (n=58) no concussions in >6 months. Known-groups approach was used with three groups at three time points (initial, 2-week and 6-week follow-up). Provoked symptoms for Gaze-Stabilization (GST), Rapid Eye Horizontal (REH), Optokinetic Stimulation (OKS), Smooth-Pursuit Slow (SPS) and Fast (SPF) tests, total combined symptoms scores and near point convergence (NPC) distance were significantly greater at initial assessment in both injury groups compared to controls. Injury groups improved on the King-Devick test and combined symptom provocation scores across time. The acute group improved over time on REH and SPF tests, while the prolonged symptoms group improved on OKS. A regression model (REH, OKS, GST) was 90% accurate discriminating concussed from healthy. Vestibular and ocular motor tests give valuable insight during recovery. They can prove beneficial in concussion evaluation given the modest equipment, training and time requirements. The current study demonstrates that when combined, vestibular and oculomotor clinical tests aid in the detection of deficits following a SRC. Additionally, tests such as NPC, GST, REH, SPS, SPF OKS and KD provide valuable information to clinicians throughout the recovery process and may aid in return to play decisions.

Loss of telomeric DNA during aging may predispose cells to cancer (review)

In normal human somatic cells, gradual shortening of telomeres may activate the complex cascade of molecular events known as cellular senescence. Experimental evidence from our laboratory suggests that cellular mortality is regulated by two separate mechanisms that we have termed mortality stage 1 (M1) and mortality stage 2 (M2). In mammary epithelial cells, the M1 mechanism involves de-regulation of p53 whereas in fibroblasts both the retinoblastoma (Rb) and p53 gene products are implicated. Cells that overcome the function of these antiproliferative proteins (M1 controls) continue to divide until a second entirely independent mechanism, M2 is induced. As somatic cells age they gradually lose telomeric sequences at the termini of their chromosomes, a process that continues during the extended lifespan period between M1 and M2. Immortal and cancer cells, as well as cells that maintain telomere length (e.g. germ cells), express telomerase, a ribonucleoprotein which maintains (stabilizes) telomere length by synthesizing TTAGGG repeats. Because normal human somatic cells and cells prior to M2 do not express telomerase, we propose that the M2 mechanism involves either the direct or indirect induction of telomerase activity. In order for cells to overcome senescence and become immortal, they must first escape the checkpoints that limit the proliferative capacity of normal cells, the MI and M2 controls (a very rare event). However, the probability of immortalization and that of tumorigenesis increases with age and we propose telomere shortening and reactivation of telomerase are important components in these processes. Once immortal, cells can then follow many pathways that result in the acquisition and progression of cancer.

Childsmile: the national child oral health improvement programme in Scotland. Part 1: Establishment and development

This paper is the first of two reviewing the Childsmile programme. It sets out to describe the development and implementation of this national oral health improvement programme for children in Scotland over its initial three-year period (January 2006 to December 2008) and into its second phase of development. It outlines the context in which the initiative was conceived, the initial development of its various components, and how monitoring and evaluation are shaping the delivery and direction of the programme.

Visual classification: expert knowledge guides machine learning

Humans use intuition and experience to classify everything they perceive, but only if the distinguishing patterns are visible. Machine-learning algorithms can learn class information from data sets, but the created classes' meaning isn't always clear. A proposed mixed-initiative approach combines intuitive visualizations with machine learning to tap into the strengths of human and machine classification. The use of visualizations in an expert-guided clustering technique allows the display of complex data sets in a way that allows human input into machine clustering. Test participants successfully employed this technique to classify analytic activities using behavioral observations of a creative-analysis task. The results demonstrate how visualization of the machine-learned classification can help users create more robust and intuitive categories.

Correlates of vitamin supplement use in the United States: data from the California Teachers Study cohort

OBJECTIVE

To describe factors associated with vitamin supplement use in a large cohort of adult women.

METHODS

California teachers and administrators (n = 133,479) completed a questionnaire on lifestyle factors and medical history. Specific supplement users regularly used at least one specific vitamin supplement in the past year; multivitamin users regularly used a multivitamin; and multivitamin and specific supplement users took a multivitamin and one or more specific supplements. Associations between supplement use and other variables were quantified using means, cross-tabulations, and age-adjusted prevalence odds ratios.

RESULTS

Multivitamin and specific supplement users tended to be older and Caucasian. Compared to non-users, they were also leaner (odds ratio [OR] for BMI > or = 30 kg/m2 = 0.6 for specific supplement users with or without multivitamins, and OR = 0.7 for multivitamin only users), and were less likely to be current smokers (OR for current smoking = 0.8 for multivitamin plus specific supplement users, OR = 0.9 for specific supplement only users, and OR = 0.7 for multivitamin only users). Specific supplement users (with or without multivitamins) were more likely to use cancer screening tests, eat fruits and vegetables, and exercise than were multivitamin only users or non-users.

CONCLUSIONS

A variety of demographic, dietary, and health-related factors were associated with different categories of supplement use.

Thick vs thin loop transurethral resection of the prostate: a double-blind prospective trial of early morbidity

OBJECTIVE

To compare blood loss, irrigation requirements and hospital stay between standard transurethral resection of the prostate (TURP) and resection incorporating vaporization, i.e. transurethral vaporization resection (TUVRP).

PATIENTS AND METHODS

Seventy patients were prospectively randomized in a blinded fashion between TURP with a standard resection loop (thin loop) or resection with a roller cutting electrode (thick loop). The outcome was assessed as the change in haemoglobin at 30 min and 24 h after the resection finished. Secondary outcome measures were irrigation requirements, length of catheterization, hospital stay, changes in serum sodium, and complications. The nursing staff and surgical registrar managing the patients after surgery were unaware of the resection technique used.

RESULTS

Data were available for 65 patients (36 thin loop and 29 thick loop resections). The mean decrease in haemoglobin after TURP was 14.8 g/L at 30 min and 11.8 g/L at 24 h; for TUVRP the corresponding values were 14.6 and 14.2 g/L (P = 0.69). In addition, there was no difference in irrigation requirements, changes in serum sodium, length of catheterization, hospital stay or bleeding complications.

CONCLUSION

The use of a thick loop at higher cutting current settings during TUVRP offers no advantage over standard thin-loop TURP.

Magnetic resonance imaging of the wrist ligaments

The advent of small arthroscopes has enabled the hand surgeon to visualize the ligaments of the wrist directly with resultant increased accuracy in diagnosing and treating pathology. Orthopaedists are now demanding a preoperative assessment and this, in turn, has necessitated that radiologists have a comprehensive understanding of wrist anatomy. High resolution MR imaging can identify the wrist ligaments reliably and provide information concerning their integrity. Interpretation is not straightforward; there is considerable anatomic variation, and there are perforations, defects and degenerative tears that can be troublesome in diagnosing injury. However, with experience and attention to anatomic detail, the radiologist can provide useful information regarding structural abnormalities. When injured, the ligaments of the wrist behave as other joint ligaments do. Findings following injury include discontinuity of normal striated bands, incomplete disruption, irregularities and alteration in normal signal. Fluid pooling around a ligament and concomitant bone injury are other clues to injury. The identification of such structural abnormalities may help to explain altered biomechanics and improve the management of patients following wrist injury.

Socioeconomic status and breast cancer incidence in California for different race/ethnic groups

OBJECTIVE

The majority of research on breast cancer risk and socioeconomic status (SES) has been conducted for blacks and whites. This study evaluates the relationship between SES and breast cancer incidence in California for four race/ethnic groups.

METHODS

Principal component analysis was used to create an SES index using 1990 Census data. Untracted cases were randomly allocated to census block groups within their county of residence. A total of 97,227 female breast cancer cases diagnosed in California between 1988 and 1992 were evaluated. Incidence rates and rate ratios (RRs) were estimated and a chi2 test for trend across SES levels was performed.

RESULTS

SES was positively related to breast cancer incidence, and this effect was stronger for Hispanics and Asian/others than for whites and blacks. Adjusting by SES did not eliminate the differences in breast cancer rates among race/ethnic groups. RR differences between the race/ethnic groups were greatest in the lowest SES category and attenuated with increasing SES. An increasing trend over SES was statistically significant for all race/ethnic groups. Including randomly allocated cases affected RR estimates for white women only.

CONCLUSIONS

Our results are consistent with similar findings for the Los Angeles area but differ from previous results for the San Francisco Bay area.

Variation in health and risk behavior among youth living with HIV

Lifetime and current health practices and risk behaviors were examined among 350 youth living with HIV (YLH) aged 14-23 years from four AIDS epicenters (72.6% male; 26.2% African American, 36.9% Latino). YLH were relatively healthy (M CD4 cells = 499), had used substantial health care and were satisfied with the care. YLH's sexual and substance-use histories indicated substantial HIV related risk acts: the median number of lifetime partners was 25 with only 8% using condoms consistently; 14.9% had injected drugs, and 61.2% had used hard drugs. Compared with females, males had more lifetime and recent sexual partners and had used more drugs. Youth who were recently sexually active (81.3%) had multiple partners. Most of the sexually active YLH used condoms consistently (81.6%). YLH who were symptomatic or had an AIDS diagnosis were likely to have recently had more seropositive sexual partners than the asymptomatic youth. Youth disclosed their serostatus to about half of their sexual partners (53.9%). YLH with AIDS used fewer hard drugs than those without an AIDS diagnosis. Health and risk behaviors of the YLH varied significantly based on their disease stage, gender, and ethnicity, suggesting the need for tailoring interventions for subgroups of YLH.

Morphine-3-D glucuronide stability in postmortem specimens exposed to bacterial enzymatic hydrolysis

Medical examiners frequently rely on the finding of free morphine present in postmortem specimens to assist in certifying deaths associated with narcotics. In vitro hydrolysis of morphine-3-D glucuronide (M3DG) to free morphine was studied using variable specimen pH, initial degree of specimen putrefaction, storage temperature and time, and the effectiveness of sodium fluoride (NaF) preservation. Reagent M3DG was added to opiate-free fresh blood and urine and to autopsy-derived blood specimens. Reagent bovine glucuronidase was also added to certain specimens. Freshly collected and refrigerated NaF-preserved blood produced minimal free morphine, whereas four of five autopsy blood specimens produced free morphine from M3DG. Increased storage time, temperature, and initial degree of putrefaction resulted in greater free morphine generation despite the absence of viable bacteria. Hydrolysis occurring during specimen storage can generate free morphine from M3DG and may result in erroneous conclusions in certifying narcotic deaths.

Substance P (Neurokinin-1) antagonist prevents postoperative vomiting after abdominal hysterectomy procedures

BACKGROUND

The safety and antiemetic efficacy of CP-122,721, a novel neurokinin-1 antagonist, was evaluated when administered alone or in combination with ondansetron.

METHODS

Using a randomized, double-blind, placebo-controlled study design, CP-122,721 was initially compared with placebo and subsequently to ondansetron alone and in combination for prophylaxis against postoperative nausea and vomiting in 243 women undergoing abdominal hysterectomy. In the dose-ranging studies (n = 86), patients received either CP-122,721 100 mg (vs. placebo) or 200 mg (vs. placebo) orally 60-90 min before induction of anesthesia. In the interaction study (n = 157), patients received CP-122,721 200 mg or placebo 60-90 min before induction of anesthesia, and ondansetron 4 mg or saline 2 ml intravenously 15-30 min before the end of surgery. Patients assessed their level of nausea and pain on arrival in the postanesthesia care unit and at 0.5-, 1-, 1.5-, 2-, 4-, 8-, 12-, and 24-h intervals postoperatively. Emetic episodes, need for rescue antiemetic-antinausea medication, postoperative complications, and patient satisfaction were recorded.

RESULTS

In the initial dose-ranging study, only 10% of the patients experienced emesis within the first 8 h after surgery with CP-122,721 200 mg compared with 50% in the placebo group. CP-122,721 200 mg also decreased the need for rescue medication (25% vs. 48%). CP-122,721 100 mg was less effective than 200 mg in decreasing the incidence of repeated episodes of emesis. In the interaction study, 6% of the patients receiving CP-122,721 200 mg orally experienced emesis less than 2 h after surgery compared with 17% with ondansetron alone. With combined therapy, only 2% experienced emesis. In addition, the median times for 75% of patients to remain free from postoperative nausea and vomiting were 82, 75, and 362 min in the ondansetron, CP-122,721, and combination groups, respectively.

CONCLUSIONS

Oral CP-122,721 200 mg decreased emetic episodes compared with ondansetron (4 mg intravenously) during the first 24 h after gynecologic surgery; however, there was no difference in patient satisfaction.

Greenland Ice Sheet: High-Elevation Balance and Peripheral Thinning

Aircraft laser-altimeter surveys over northern Greenland in 1994 and 1999 have been coupled with previously reported data from southern Greenland to analyze the recent mass-balance of the Greenland Ice Sheet. Above 2000 meters elevation, the ice sheet is in balance on average but has some regions of local thickening or thinning. Thinning predominates at lower elevations, with rates exceeding 1 meter per year close to the coast. Interpolation of our results between flight lines indicates a net loss of about 51 cubic kilometers of ice per year from the entire ice sheet, sufficient to raise sea level by 0.13 millimeter per year-approximately 7% of the observed rise.

Providing clinical opportunities for youths affected by HIV

Individual counseling, as invaluable as it is for HIV-affected youth, is just one forum in which young people can receive clinical assistance. The youth-centered programs noted previously and others carried out in various agencies around the country offer HIV-affected youth an opportunity to receive clinical experiences while focusing on their strengths and interests. A nonthreatening atmosphere in which many children are invited to participate is essential for helping young people feel comfortable and connected to the agency. When children develop friendships through the agency, they can begin to feel less alone in their situation and more willing to reach out to others--clinicians and peers--for help. An increased trust in the agency can help HIV-affected young people maintain an ongoing connection to services and open the door to traditional counseling. As children become more engaged in the agency and begin to develop a sense of ownership, they may want to take on more responsibility. Leadership programs that focus on young people's skills and talents can help establish the agency as a place that is safe for youths on their own terms. That may involve activities such as older children serving as mentors for younger ones, performing community projects in their neighborhoods, doing outreach to help connect more people to the programs, or designing and running their own conferences for youth. Collaboration with other agencies for special projects can help link children to additional programs and to other youth, thus decreasing their isolation. Childhood and adolescence is a time of rapid changes accompanied by emotional fluctuations. Young people feel emotions intensely, but often lack the cognitive ability necessary to articulate them. When a young person is coping with the illness or death of a parent from AIDS in addition to all the pressures and changes in life, the experience of growing up is even more difficult and complicated. The emotional flux, confusion, and life transitions can lead to impulsive and self-destructive behavior. But childhood and adolescence is also a time of heightened energy, creativity, resilience, and hope. Programs for HIV-affected youth need to balance the attention paid to the challenges they face and the strengths they possess. When allowed to grow and shine, affected young people may begin to express some of their emotional needs. Caring workers can then help them make sense of their experiences and mature into the successful adults they all have the potential to become.

PRINTS-S: the database formerly known as PRINTS

The PRINTS database houses a collection of protein family fingerprints. These are groups of motifs that together are diagnostically more potent than single motifs by virtue of the biological context afforded by matching motif neighbours. Around 1200 fingerprints have now been created and stored in the database. The September 1999 release (version 24.0) encodes approximately 7200 motifs, covering a range of globular and membrane proteins, modular polypeptides and so on. In addition to its continued steady growth, we report here several major changes to the resource, including the design of an automated strategy for database maintenance, and implementation of an object-relational schema for more efficient data management. The database is accessible for BLAST, fingerprint and text searches at http://www.bioinf.man.ac. uk/dbbrowser/PRINTS/

Historical analogies, slippery slopes, and the question of euthanasia

The German Nazi regime has become a standard model for unspeakable things that one should reject. Contemporary people will characterize political opponents, benighted policies, and other undesirable things as “fascist” or “Nazi.” In ethics, and medical ethics in particular, this analogy arises regularly. Therefore, it is not surprising that German people are particularly sensitive about their history. For example, the German high court regularly refers to the Nazi era in its reluctance to accept lethal social activities. This sensitivity surfaced again in 1988, when influential applied ethicist Peter Singer accepted a German invitation to speak to a Symposium on “Bioengineering, Ethics, and Mental Disability.” Singer had also agreed to deliver a separate lecture on the topic “Do severely disabled newborn infants have a right to life?”

Comparison of ondansetron and cyclizine for prevention of nausea and vomiting after day-case gynaecological laparoscopy

We have compared ondansetron 4 mg i.v. and cyclizine 50 mg i.v., in a double-blind, randomized, placebo-controlled study for the prevention of postoperative nausea and vomiting (PONV) for 24 h after day-case gynaecological laparoscopy. Compared with placebo (n = 58), ondansetron (n = 60) and cyclizine (n = 57) reduced significantly the incidence of moderate or severe nausea (30% and 23% vs 52%; P = 0.02 and P = 0.001, respectively) and requirement for escape antiemetic (28% and 16% vs 47%; P = 0.04 and P < 0.001, respectively) before discharge from hospital. There were no significant differences in PONV after discharge. Significantly more patients suffered no PONV before and after discharge after ondansetron and cyclizine compared with placebo (31% and 33% vs 12%; P = 0.02 and P < 0.01, respectively). For diagnostic laparoscopy (n = 74), fewer patients received escape antiemetic after cyclizine than after ondansetron (4% vs 37%; P < 0.01); for laparoscopic sterilization (n = 101), both antiemetics were equally effective. Ondansetron and cyclizine both reduced severe and moderate nausea and the need for antiemetic therapy after day-case gynaecological laparoscopy.

BLAST PRINTS--alternative perspectives on sequence similarity

SUMMARY

An implementation of BLAST for searching the PRINTS database is presented. The interface allows submission of either protein or DNA queries, and returns the familiar form of output, but modified by means of direct links both to the familial discriminators in PRINTS and to fingerprint profile visualization software. The server thus couples the rapidity of BLAST searching with the sensitivity of fingerprint diagnoses, providing alternative perspectives on a given query.

AVAILABILITY

http://www.biochem.ucl. ac.uk/cgi-bin/wright/printsBLAST.cgi

Rapid thinning of parts of the southern greenland ice sheet

Aircraft laser-altimeter surveys over southern Greenland in 1993 and 1998 show three areas of thickening by more than 10 centimeters per year in the southern part of the region and large areas of thinning, particularly in the east. Above 2000 meters elevation the ice sheet is in balance but thinning predominates at lower elevations, with rates exceeding 1 meter per year on east coast outlet glaciers. These high thinning rates occur at different latitudes and at elevations up to 1500 meters, which suggests that they are caused by increased rates of creep thinning rather than by excessive melting. Taken as a whole, the surveyed region is in negative balance.

PRINTS prepares for the new millennium

PRINTS is a diagnostic collection of protein fingerprints. Fingerprints exploit groups of motifs to build characteristic family signatures, offering improved diagnostic reliability over single-motif approaches by virtue of the mutual context provided by motif neighbours. Around 1000 fingerprints have now been created and stored in PRINTS. The September 1998 release (version 20.0), encodes approximately 5700 motifs, covering a range of globular and membrane proteins, modular polypeptides and so on. The database is accessible via the DbBrowser Web Server at http://www.biochem.ucl.ac.uk/bsm/dbbrowser /. In addition to supporting its continued growth, recent enhancements to the resource include a BLAST server, and more efficient fingerprint search software, with improved statistics for estimating the reliability of retrieved matches. Current efforts are focused on the design of more automated methods for database maintenance; implementation of an object-relational schema for efficient data management; and integration with PROSITE, profiles, Pfam and ProDom, as part of the international InterPro project, which aims to unify protein pattern databases and offer improved tools for genome analysis.

Social class and health: the puzzling counter-example of British South Asians

British South Asians (with ancestry from the Indian subcontinent) provided a puzzling exception to the British class gradient in mortality during the 1970s. On the assumption that class gradients in health are produced mainly by gradients in standard of living, this might be due to a break in the relation of class to standard of living (change in class structure), or by a break in the relation of standard of living to patterns of health behaviour and health risk (change in class lifestyles). Data on these characteristics are available from the West of Scotland Twenty-07 Study, where 159 South Asians aged 30-40 (mean age 35) were sampled alongside 319 of the general population in Glasgow. As regards changes in class structure, results indicate that the underclass thesis, which suggests that ethnic minorities are forced into less eligible jobs or into a separate labour market or into unemployment, resulting in a standard of living below that of the general population, still holds good for British South Asians in categories from social class III non-manual downwards. It does not hold good for owners of small businesses, where Sikhs and Hindus in particular have a standard of living equivalent to general population counterparts. However, prosperity is not predictable from levels of education in the subcontinent and from this and other signs it appears that a wholesale redistribution of class chances is occurring among British South Asians, disrupting inter-and intra-generational continuities in the relation between class and standard of living. There is little sign of change in class lifestyles, i.e. in the relation between standard of living and health behaviour or health risk. As yet, though, the new distribution of standard of living is affecting patterns of health behaviour and health risk more strongly than symptom experience or chronic illness, suggesting that a class gradient in health will re-emerge.

Human gene therapy for melanoma: CT-guided interstitial injection

OBJECTIVE

Our intent is to describe the role of CT in the intratumoral injection of Allovectin-7 (Vical, San Diego, CA), an allogeneic class I major histocompatibility complex antigen, HLA-B7, formulated with cationic lipid, in the treatment of metastatic malignant melanoma.

MATERIALS AND METHODS

Ten patients with metastatic malignant melanoma were treated with gene therapy in which we used CT-guided intratumoral injection of plasmid DNA containing the HLA-B7 gene. This therapy was part of a phase I gene therapy trial in patients with metastatic melanoma. CT guidance was chosen as an accurate way to direct gene delivery in patients with deep, impalpable lesions. Tumor locations included pulmonary, mediastinal, hepatic, adrenal, and paracaval sites. Patients in the CT protocol underwent baseline CT studies. Examinations were repeated 2, 4, and 8 weeks after gene therapy and thereafter at 3-month intervals. Both injected and noninjected tumors were measured. CT-guided injections of 10, 50, or 250 micrograms of plasmid DNA were performed with 22-gauge spinal needles. Injection volumes were between 1.0 and 4.0 ml, depending on tumor size. CT-guided core biopsy specimens were obtained (with 18- or 20-gauge needles) from the selected tumor before therapy and 2, 4, and 8 weeks after therapy to assess HLA-B7 plasmid DNA and gene expression. Peripheral blood was analyzed for cytotoxic T lymphocytes directed against HLA-B7.

RESULTS

CT-guided intratumoral injections were successful in delivering genetic material to all patients with impalpable tumors. Significant responses (as defined by a decrease of 25% or more in the product of the length and width of the injected tumor) were observed in six of the 10 patients. One of these six patients who had a solitary lesion remains free of disease 19 months after gene therapy. HLA-B7 protein expression was detected in 89% of biopsy specimens, and plasmid DNA and messenger RNA were detected in 56% and 22% of biopsy specimens, respectively.

CONCLUSION

CT provides a safe, accurate, and efficacious way to monitor and assess tumor progression and response, and it provides guidance for biopsies and intratumoral injections during gene therapy. Significant responses in injected tumors of six of the 10 patients in our study suggest that further clinical trials of this gene therapy are warranted.

Air-coupled Lamb wave tomography

An entirely air-coupled inspection system using a pair of micromachined silicon capacitance transducers has been used to image defects in thin plates of different materials (0.7 mm to 2.22 mm thick) using air-coupled Lamb wave tomography. A filtered back projection algorithm was used in a form of difference tomography to reconstruct images of defects up to 10 mm diameter machined in aluminium and perspex (Plexiglas) plates, as well as in samples of carbon fiber reinforced polymer (CFRP). The technique was able to resolve non-central defects as well as multiple flaws within the scan area. This flexible tomographic system was able to produce images of the change in a variety of different acoustic variables from only one set of experimental data, with success dependent on the size, shape, and location of the defect in the scan area.

A skeletal muscle-specific enhancer regulated by factors binding to E and CArG boxes is present in the promoter of the mouse myosin light-chain 1A gene

The mouse myosin light-chain 1A (MLC1A) gene, expressed in the atria of the adult heart, is one of the first muscle genes to be activated when skeletal as well as cardiac muscles form in the embryo. It is also transcribed in skeletal muscle cell lines at the onset of differentiation. Transient transfection assays of mouse skeletal muscle cell lines with DNA constructs containing MLC1A promoter fragments fused to the chloramphenicol acetyltransferase (CAT) gene show that the first 630 bp of the promoter is sufficient to direct expression of the reporter gene during myotube formation. Two E boxes located at bp -76 and -519 are necessary for this regulation. MyoD and myogenin proteins bind to them as heterodimers with E12 protein and, moreover, transactivate them in cotransfection experiments with the MLC1A promoter in nonmuscle cells. Interestingly, the effect of mutating each E box is less striking in primary cultures than in the C2 or Sol8 muscle cell line. A DNA fragment from bp -36 to -597 confers tissue- and stage-specific activity to the herpes simplex virus thymidine kinase promoter in both orientations, showing that the skeletal muscle-specific regulation of the MLC1A gene is under the control of a muscle-specific enhancer which extends into the proximal promoter region. At bp -89 is a diverged CArG box, CC(A/T)6AG, which binds the serum response factor (SRF) in myotube nuclear extracts, as does the wild-type sequence, CC(A/T)6GG. Both types of CArG box also bind a novel myotube-enriched complex which has contact points with the AT-rich part of the CArG box and adjacent 3' nucleotides. Mutations within the CArG box distinguish between the binding of this complex and binding of SRF; only SRF binding is directly involved in the specific regulation of the MLC1A gene in skeletal muscle cell lines.

Conformational analysis of molecular chains using nano-kinematics

We present algorithms for 3-D manipulation and conformational analysis of molecular chains, when bond lengths, bond angles and related dihedral angles remain fixed. These algorithms are useful for local deformations of linear molecules, exact ring closure in cyclic molecules and molecular embedding for short chains. Other possible applications include structure prediction, protein folding, conformation energy analysis and 3D molecular matching and docking. The algorithms are applicable to all serial molecular chains and make no assumptions about their geometry. We make use of results on direct and inverse kinematics from robotics and mechanics literature and show the correspondence between kinematics and conformational analysis of molecules. In particular, we pose these problems algebraically and compute all the solutions making use of the structure of these equations and matrix computations. The algorithms have been implemented and perform well in practice. In particular, they take tens of milliseconds on current workstations for local deformations and chain closures on molecular chains consisting of six or fewer rotatable dihedral angles.

Clinical microleakage evaluation of a cavity varnish

This clinical study evaluated the microleakage effectiveness of a cavity varnish when used in combination with two types of amalgam: a spherical particle and a dispersed phase alloy. Calcium hydroxide was utilized as the microleakage detection agent. Copalite showed a reduction in microleakage when it was employed with the spherical particle alloy used in this study. This study clinically demonstrated that Copalite is not totally effective in eliminating microleakage.

Initial characterization of heat-induced excess nuclear proteins in HeLa cells

Exposure of mammalian cells to hyperthermia is known to cause protein aggregation in the nucleus. The presence of such aggregates has been detected as the relative increase in the protein mass that is associated with nuclei isolated from heated cells. We have characterized these excess nuclear proteins from the nuclei of heated HeLa cells by two-dimensional gel electrophoresis. The abundance of cytoskeletal elements which co-purify with the nuclei did not increase with exposure to hyperthermia, indicating that these proteins are not part of the excess nuclear proteins. In contrast, several specific polypeptides become newly bound or increase in abundance in nuclei isolated from heated cells. Members of the hsp 70 family were identified as a major component of the excess nuclear proteins. Among the other excess nuclear proteins we identified ten that had apparent molecular weights of 130, 95, 75, 58, 53, 48, 46, 37, 28, and 26 kilodaltons. Since hsp 70 is mainly cytoplasmic in non-heated cells, its association with nuclei in heated cells indicates that one mechanism accounting for the heat-induced excess nuclear proteins is the movement of cytoplasmic proteins to the nucleus. We also obtained evidence that increased binding of nuclear proteins is another mechanism for this effect. No overall increase or decrease in the phosphorylation of nuclear proteins was found to be associated with such altered binding or movement from the cytoplasm to the nucleus.

Propranolol pretreatment reduces cardiorespiratory toxicity due to plain, but not epinephrine-containing, intravenous bupivacaine in rats

The purpose of this study was to evaluate the effects of pretreatment with propranolol on the cardio-respiratory toxicity of bupivacaine, either plain or with epinephrine 1:200,000 (5 micrograms.ml-1) added. Adult male Sprague Dawley rats, anaesthetized with intraperitoneal pentobarbital, were divided into four groups. Groups I and III were pretreated with iv propranolol 150 micrograms.kg-1, and Groups II and IV received iv NS as a placebo. Three minutes later, rats in Groups I and II received plain 0.5% bupivacaine, 4 mg.kg-1, and Groups III and IV received 4 mg.kg-1 of 0.5% bupivacaine with epinephrine, 5 micrograms.ml-1 iv. Five of eight rats pretreated with propranolol survived (Group I), compared with uniform fatality with NS pretreatment (Group II) (P less than 0.05). Addition of epinephrine to the bupivacaine eliminated the protective effect of propranolol. All rats pretreated with propranolol (Group III) or NS (Group IV) died when given bupivacaine with epinephrine. In conclusion, acute propranolol pretreatment reduced the fatal cardiotoxicity due to iv bupivacaine in male Sprague Dawley rats, but the addition of epinephrine 5 micrograms.ml-1 to bupivacaine eliminated the protective effect of propranolol.

Nicardipine reduces the cardio-respiratory toxicity of intravenously administered bupivacaine in rats

The purpose of our study was to examine the effect of intravenous (IV) nicardipine pretreatment (30 micrograms.kg-1), given three minutes before an IV bolus of bupivacaine to determine its effect on the incidence of fatal bupivacaine cardio-respiratory toxicity in adult male Sprague Dawley rats anaesthetized with intraperitoneal pentobarbital. Fifty rats were divided into four groups. Groups I and II (n = 10 each) received 3.5 mg.kg-1 0.5 per cent bupivacaine and Groups III and IV (n = 15 each) received 5.0 mg.kg-1, 0.5 per cent bupivacaine. Groups I and III received pretreatment with normal saline before bupivacaine, whereas Groups II and IV were given pretreatment with nicardipine, 30 mg.kg-1. There was no difference in the incidence of survival between the nicardipine pretreatment group and the saline placebo pretreatment group given 3.5 mg.kg-1, 0.5 per cent bupivacaine (no fatalities in either group). However, there was significant protection by nicardipine pretreatment in the group given 5 mg.kg-1, 0.5 per cent bupivacaine (13 of 15 survived, compared with only 4 of 15 in the saline pretreatment group, P less than 0.001). In conclusion, our data demonstrate that in rats given 0.5 per cent bupivacaine, 5 mg.kg-1, nicardipine pretreatment protected against fatal cardio-respiratory toxicity.