Valaciclovir for Epstein-Barr Virus Suppression in Moderate-to-Severe COPD: A Randomized Double-Blind Placebo-Controlled Trial

BACKGROUND

Epstein-Barr virus (EBV) frequently is measured at high levels in COPD using sputum quantitative polymerase chain reaction, whereas airway immunohistochemistry analysis has shown EBV detection to be common in severe disease.

RESEARCH QUESTION

Is valaciclovir safe and effective for EBV suppression in COPD?

STUDY DESIGN AND METHODS

The Epstein-Barr Virus Suppression in COPD (EViSCO) trial was a randomized double-blind placebo-controlled trial conducted at the Mater Hospital Belfast, Northern Ireland. Eligible patients had stable moderate-to-severe COPD and sputum EBV (measured using quantitative polymerase chain reaction) and were assigned randomly (1:1) to valaciclovir (1 g tid) or matching placebo for 8 weeks. The primary efficacy outcome was sputum EBV suppression (defined as ≥ 90% sputum viral load reduction) at week 8. The primary safety outcome was the incidence of serious adverse reactions. Secondary outcome measures were FEV1 and drug tolerability. Exploratory outcomes included changes in quality of life, sputum cell counts, and cytokines.

RESULTS

From November 2, 2018, through March 12, 2020, 84 patients were assigned randomly (n = 43 to valaciclovir). Eighty-one patients completed trial follow-up and were included in the intention-to-treat analysis of the primary outcome. A greater number of participants in the valaciclovir group achieved EBV suppression (n = 36 [87.8%] vs n = 17 [42.5%]; P < .001). Valaciclovir was associated with a significant reduction in sputum EBV titer compared with placebo (-90,404 copies/mL [interquartile range, -298,000 to -15,200 copies/mL] vs -3,940 copies/mL [interquartile range, -114,400 to 50,150 copies/mL]; P = .002). A statistically nonsignificant 24-mL numerical FEV1 increase was shown in the valaciclovir group (difference, -44 mL [95% CI, -150 to 62 mL]; P = .41). However, a reduction in sputum white cell count was noted in the valaciclovir group compared with the placebo group (difference, 2.89 [95% CI, 1.5 × 106-7.4 × 106]; P = .003).

INTERPRETATION

Valaciclovir is safe and effective for EBV suppression in COPD and may attenuate the sputum inflammatory cell infiltrate. The findings from the current study provide support for a larger trial to evaluate long-term clinical outcomes.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT03699904; URL: www.

CLINICALTRIALS

gov.

School-based relationship and sexuality education intervention engaging adolescent boys for the reductions of teenage pregnancy: the JACK cluster RCT

Background

The need to engage boys in gender-transformative relationships and sexuality education (RSE) to reduce adolescent pregnancy is endorsed by the World Health Organization and the United Nations Educational, Scientific and Cultural Organization.

Objectives

To evaluate the effects of If I Were Jack on the avoidance of unprotected sex and other sexual health outcomes.

Design

A cluster randomised trial, incorporating health economics and process evaluations.

Setting

Sixty-six schools across the four nations of the UK.

Participants

Students aged 13-14 years.

Intervention

A school-based, teacher-delivered, gender-transformative RSE intervention (If I Were Jack) versus standard RSE.

Main outcome measures

Self-reported avoidance of unprotected sex (sexual abstinence or reliable contraceptive use at last sex) after 12-14 months. Secondary outcomes included knowledge, attitudes, skills, intentions and sexual behaviours.

Results

The analysis population comprised 6556 students: 86.6% of students in the intervention group avoided unprotected sex, compared with 86.4% in the control group {adjusted odds ratio 0.85 [95% confidence interval (CI) 0.58 to 1.26], p = 0.42}. An exploratory post hoc analysis showed no difference for sexual abstinence [78.30% intervention group vs. 78.25% control group; adjusted odds ratio 0.85 (95% CI 0.58 to 1.24), p = 0.39], but more intervention group students than control group students used reliable contraception at last sex [39.62% vs. 26.36%; adjusted odds ratio 0.52 (95% CI 0.29 to 0.920), p = 0.025]. Students in schools allocated to receive the intervention had significantly higher scores on knowledge [adjusted mean difference 0.18 (95% CI 0.024 to 0.34), p = 0.02], gender-equitable attitudes and intentions to avoid unintended pregnancy [adjusted mean difference 0.61 (95% CI 0.16 to 1.07), p = 0.01] than students in schools allocated to receive the control. There were positive but non-significant differences in sexual self-efficacy and communication skills. The total mean incremental cost of the intervention compared with standard RSE was £2.83 (95% CI -£2.64 to £8.29) per student. Over a 20-year time horizon, the intervention is likely to be cost-effective owing to its impact on unprotected sex because it would result in 379 (95% CI 231 to 477) fewer unintended pregnancies, 680 (95% CI 189 to 1467) fewer sexually transmitted infections and a gain of 10 (95% CI 5 to 16) quality-adjusted life-years per 100,000 students for a cost saving of £9.89 (95% CI -£15.60 to -£3.83).

Limitations

The trial is underpowered to detect some effects because four schools withdrew and the intraclass correlation coefficient (0.12) was larger than that in sample size calculation (0.01).

Conclusions

We present, to our knowledge, the first evidence from a randomised trial that a school-based, male engagement gender-transformative RSE intervention, although not effective in increasing avoidance of unprotected sex (defined as sexual abstinence or use of reliable contraception at last sex) among all students, did increase the use of reliable contraception at last sex among students who were, or became, sexually active by 12-14 months after the intervention. The trial demonstrated that engaging all adolescents early through RSE is important so that, as they become sexually active, rates of unprotected sex are reduced, and that doing so is likely to be cost-effective.

Future work

Future studies should consider the longer-term effects of gender-transformative RSE as students become sexually active. Gender-transformative RSE could be adapted to address broader sexual health and other settings.

Trial registration

This trial is registered as ISRCTN10751359.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme (PHR 15/181/01) and will be published in full in Public Health Research; Vol. 11, No. 8. See the NIHR Journals Library website for further project information.

Acute hypoxaemic respiratory failure after treatment with lower tidal volume ventilation facilitated by extracorporeal carbon dioxide removal: long-term outcomes from the REST randomised trial

INTRODUCTION

Lower tidal volume ventilation, facilitated by veno-venous extracorporeal carbon dioxide removal (vv-ECCO2R), does not improve 90-day mortality in patients with acute hypoxaemic respiratory failure (AHRF). The aim of this analysis was to evaluate the effect of this therapeutic strategy on long-term outcomes.

METHODS

This was a prespecified analysis of the REST trial, a UK-wide multicentre randomised clinical trial that compared lower tidal volume ventilation, facilitated by vv-ECCO2R (intervention), with standard care in the treatment of patients with moderate-to-severe AHRF. Mortality to 2 years was assessed, while respiratory function, post-traumatic stress disorder, cognitive function and health-related quality of life were evaluated in survivors at 1 year using standardised questionnaires.

RESULTS

Of 412 patients enrolled into the REST trial, 391 (95%) had 2-year mortality outcome data available. There was no difference in the time to death between intervention and standard care (HR 1.08 (0.81, 1.44); log-rank test p=0.61). 161 patients alive at 1 year provided at least one questionnaire response. There was no difference in respiratory function, post-traumatic stress disorder, cognitive dysfunction or health-related quality of life between patients allocated to intervention or standard care.

CONCLUSION

Lower-tidal volume ventilation facilitated by vv-ECCO2R does not affect 1-year mortality in patients with moderate-to-severe AHRF. Of the patients who provided questionnaire responses, there was no treatment effect on long-term respiratory function, post-traumatic stress disorder, cognitive dysfunction or health-related quality of life.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov identifier: NCT02654327.

Whole Dietary Patterns, Cognitive Decline and Cognitive Disorders: A Systematic Review of Prospective and Intervention Studies

Dementia prevalence is a global public health concern. Adherence towards a healthy dietary pattern (DP) may reduce the risk of cognitive decline and dementia. This narrative systematic review aimed to synthesise prospective and intervention study data to evaluate the impact of a-posteriori and a-priori derived DPs on cognitive ageing, from cognitive decline to incident dementia. Ninety-three studies were included: 83 prospective studies and 10 randomised controlled trials (RCT). Most prospective studies (77%) examined a-priori DPs, with the Mediterranean diet examined most frequently. A total of 52% of prospective and 50% of RCTs reported a protective relationship between 'healthy' DPs and global cognitive decline. Overall, 59% of prospective studies reported positive associations between healthy DPs and risk of cognitive disorder. Incident cognitive disorder was examined by only one intervention study (subgroup analysis) which reported a beneficial effect of a low-fat diet on risk of probable dementia in women. Unhealthy DPs were examined less frequently (n = 17; 21%), with 41% of these studies reporting associations between adherence and poorer cognitive outcomes. Overall, there were mixed results for healthy and unhealthy DPs on cognition, likely due to between-study heterogeneity. Standardisation of diet exposure and cognitive outcome measurement would help to reduce this. Future research would benefit from investigating effects of culturally appropriate DPs on individual cognitive domains and incident cognitive disorders in diverse and high-risk populations.

An external pilot cluster randomised controlled trial of a theory-based intervention to improve appropriate polypharmacy in older people in primary care (PolyPrime)

Background

For older populations with multimorbidity, polypharmacy (use of multiple medications) is a standard practice. PolyPrime is a theory-based intervention developed to improve appropriate polypharmacy in older people in primary care. This pilot study aims to assess the feasibility of the PolyPrime intervention in primary care in Northern Ireland (NI) and the Republic of Ireland (ROI).

Methods

This external pilot cluster randomised controlled trial (cRCT) aimed to recruit 12 general practitioner (GP) practices (six in NI; six in the ROI counties that border NI) and ten older patients receiving polypharmacy (≥ 4 medications) per GP practice (n = 120). Practices allocated to the intervention arm watched an online video and scheduled medication reviews with patients on two occasions. We assessed the feasibility of collecting GP record (medication appropriateness, health service use) and patient self-reported data [health-related quality of life (HRQoL), health service use)] at baseline, 6 and 9 months. HRQoL was measured using the EuroQol-5 dimension-5 level questionnaire (EQ-5D-5L) and medication-related burden quality-of-life (MRB-QoL) tool. An embedded process evaluation and health economics analysis were also undertaken. Pre-specified progression criteria were used to determine whether to proceed to a definitive cRCT.

Results

Twelve GP practices were recruited and randomised. Three GP practices withdrew from the study due to COVID-related factors. Sixty-eight patients were recruited, with 47 (69.1%) being retained until the end of the study. GP record data were available for 47 patients for medication appropriateness analysis at 9 months. EQ-5D-5L and MRB-QoL data were available for 46 and 41 patients, respectively, at 9 months. GP record and patient self-reported health service use data were available for 47 patients at 9 months. Health service use was comparable in terms of overall cost estimated from GP record versus patient self-reported data. The intervention was successfully delivered as intended; it was acceptable to GPs, practice staff, and patients; and potential mechanisms of action have been identified. All five progression criteria were met (two ‘Go’, three ‘Amend’).

Conclusion

Despite challenges faced during the COVID-19 pandemic, this study has demonstrated that it may be feasible to conduct an intervention to improve appropriate polypharmacy in older people in primary care across two healthcare jurisdictions.

Trial registration

ISRCTN, ISRCTN41009897. Registered 19 November 2019. Clinicaltrials.gov, NCT04181879. Registered 02 December 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-01161-6.

Association between oral health status and future dietary intake and diet quality in older men: The PRIME study

OBJECTIVES

This study investigated whether oral health status, defined as number of natural teeth and subsequent prosthodontic rehabilitation, was associated with future dietary intake and diet quality in older adults in The Prospective Epidemiological Study of Myocardial Infarction (PRIME).

METHODS

PRIME was originally established to explore cardiovascular risk factors in 50-59 year old men in Northern Ireland (1991-1994). A rescreening phase assessed oral health (2001-2004), while diet was assessed in 2015. Diet quality was characterised by the Dietary Diversity Score and Mediterranean Diet Score. In the current analysis, associations between oral health status, dietary intake and quality were assessed using regression models in 1096 participants.

RESULTS

Amongst study participants, the overall mean number of teeth was 18.5, 51.5 % had ≥21 natural teeth and 49.6 % wore dentures. Oral health status was categorised into five groups: 21-28 teeth with (n = 111) and without (n = 453) dentures, 1-20 teeth with (n = 354) and without (n = 99) dentures and edentate with dentures (n = 79). After full adjustment, men with ≥21 teeth and dentures had a higher future intake of fruit, vegetables, and nuts, and diet quality scores, compared to those with <21 teeth with dentures. Edentate men with dentures were less likely to achieve the future fruit dietary recommendation.

CONCLUSIONS

Having ≥21 natural remaining teeth positively affected the future intake of fruit, vegetables, and nuts, as well as diet quality. Dentures may be beneficial in men with ≥21 natural remaining teeth, as they were associated with an increased future intake of fruit, vegetables, and nuts and better diet quality.

CLINICAL SIGNIFICANCE

Oral health status is associated with dietary intake, after an average time period of 13 years, with those with a larger number of natural teeth having a better diet quality. Further research is required to investigate this relationship in larger, diverse populations with more detailed dietary assessment.

Impact of Oral Health Status on Future Dietary Intake and Dietary Quality in Older Adults in Northern Ireland: A Longitudinal Analysis (P18-080-19)

Objectives

Evidence linking oral health status with dietary intake and quality in older adults is inconsistent and limited by few prospective studies conducted to date. This study investigated whether oral health status, defined as number of natural teeth and prosthodontic rehabilitation, had an impact on future dietary intake and dietary quality in older Northern Irish (NI) men.

Methods

This study involved older men [n = 1096, mean = 63.5(2.9) years] from the Prospective Epidemiological Study of Myocardial Infarction (PRIME). A dental examination was undertaken at baseline (2001–2006) and oral health status was defined as: 21–28 teeth without dentures (n = 453), 21–28 teeth with dentures (n = 111), 1–20 teeth without dentures (n = 99), 1–20 teeth with dentures (n = 354), and edentate with dentures (n = 79). A food frequency questionnaire administered in 2015 derived intakes of major food groups and diet quality scores were characterised by the Dietary Diversity Score (DDS) and Mediterranean Diet Score (MDS). Associations between oral health status, food intake and diet quality scores were assessed using regression models adjusted for potential confounders including, age, socio-economic status, smoking and alcohol.

Results

In fully adjusted models, the mean dietary intake of fruit, vegetables and nuts significantly differed between oral health status groups. In comparison to edentate men with dentures, the mean fruit intake was significantly higher in each dentate group: 21–28 teeth without dentures (P = 0.001), 21–28 teeth with dentures (P = 0.001), 1–20 teeth without dentures (P = 0.04), and 1–20 teeth with dentures (P = 0.03). The mean DDS was significantly higher amongst men with 21–28 teeth without dentures, compared to those with 1–20 teeth without dentures (P = 0.001), 1–20 teeth with dentures (P < 0.001), and edentate with dentures (P < 0.001), and mean MDS results were similar. Compared to men with 21–28 teeth without dentures, edentate men with dentures were 64% less likely to achieve the dietary guideline of 2 portions/day (P = 0.01).

Conclusions

A greater number of natural teeth was associated with a higher future intake of fruit, vegetables and nuts, as well as higher dietary quality scores, in older NI men. Interventions should optimise retaining natural teeth to help improve dietary intake and quality in older adults.

Funding Sources

Department of Economy funded PhD.

Are older drivers' driving patterns during an on-road driving task representative of their real-world driving patterns?

OBJECTIVE

The current study investigated whether older drivers' driving patterns during a customized on-road driving task were representative of their real-world driving patterns.

METHODS

Two hundred and eight participants (male: 68.80%; mean age = 81.52 years, SD = 3.37 years, range = 76.00-96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants' real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant's vehicle.

RESULTS

During the 4-month period prior to completing the on-road driving task, participants' median real-world driving trip distance was 2.66 km (interquartile range [IQR] = 1.14-5.79 km) and their median on-road driving task trip distance was 4.41 km (IQR = 2.83-6.35 km). Most participants' on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n = 198).

CONCLUSIONS

These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants' real-world driving patterns.

Systems biology of the neurospora biological clock

A major challenge of systems biology is explaining complex traits, such as the biological clock, in terms of the kinetics of macromolecules. The clock poses at least four challenges for systems biology: (i) identifying the genetic network to explain the clock mechanism quantitatively; (ii) specifying the clock's functional connection to a thousand or more genes and their products in the genome; (iii) explaining the clock's response to light and other environmental cues; and (iv) explaining how the clock's genetic network evolves. Here, the authors illustrate an approach to these problems by fitting an ensemble of genetic networks to microarray data derived from oligonucleotide arrays with approximately all 11 000 Neurospora crassa genes represented. A promising genetic network for the clock mechanism is identified.

Measuring women's preferences for breast cancer treatments and BRCA1/BRCA2 testing

In establishing decision models in the treatment and prevention of breast cancer, it is important to evaluate patients' preferences for such interventions. The objectives of the present study were: (i) to characterize women's preferences for breast cancer treatments and BRCA1/BRCA2 testing, using the rating scale and standard gamble techniques; and (ii) to identify factors associated with these quality of life indices. Data were collected from women with breast cancer (n = 60), high-risk relatives of women with breast cancer (n = 58), and women in the general population (n = 51). Regardless of group membership, participants favoured treatment and prevention options that involved minimal physical invasiveness. Women with breast cancer rated lumpectomy and radiation treatment more highly than high-risk relatives and women in the general population. Preferences did not differ according to participants' intentions to undergo BRCA testing. Age was the only demographic variable associated with health state preferences. These findings hold implications for the application of patient preferences to clinical decision making.

Canadian oncologists and clinical practice guidelines: a national survey of attitudes and reported use. Provincial Lung Disease Site Group of Cancer Care Ontario

PURPOSE

To determine (1) Canadian oncologists' attitudes toward practice guidelines, (2) oncologists' self-reported use of practice guidelines and, (3) physicians' characteristics and attitudes associated with self-reported use of practice guidelines.

PARTICIPANTS AND METHODS

A cross-sectional, self-administered postal survey was administered to Canadian oncologists. Main outcome measures were level of agreement with 8 descriptive statements about guidelines, score on the attitudinal scale of the guideline of Tunis et al., and physicians' stated use of guideline. chi(2) and logistic regression procedures were used to explore the relationship between physician characteristics and use of guidelines.

RESULTS

Over 80% of respondents agreed that they were good educational tools, convenient sources of advice, intended to improve quality of care; over 40% agreed that they were unbiased syntheses of expert opinion. Conversely, 42, 26, 20 and 16% felt they were intended to cut costs, were oversimplified cookbook medicine, were too rigid to apply to individual patients, and a challenge to physicians' authority, respectively. Forty-one percent reported using practice guidelines routinely or most of the time. Use was associated with positive attitudes about guidelines, receiving medical school training abroad and being a radiation oncologist.

CONCLUSION

Canadian oncologists were quite positive about practice guidelines and reported using them frequently. Our results suggest that use of guidelines by oncologists may be related to attitudes about guidelines in general, specialty within oncology and country of medical school training.

Aggressive behavior in clinically depressed adolescents

OBJECTIVE

To investigate the prevalence and characteristics of aggressive behavior in adolescent inpatients and outpatients with major depressive disorder (MDD). Differences between males and females in prevalence and type of aggression, and level of parent-child agreement in report of aggression, were analyzed.

METHOD

Participants were 74 adolescents with MDD, aged 13 to 17 years. The Structured Clinical Interview for DSM-IV Axis I Disorders was used to identify MDD. Adolescents' aggressive behavior was assessed using an adapted version of the Brown-Goodwin Assessment for Lifetime History of Aggression; the Measure of Aggression, Violence, and Rage in Children; and the Buss-Durkee Hostility Inventory-Adapted Version.

RESULTS

Results indicate high levels of aggressive behavior in adolescents with MDD. Amount and type of aggression did not differ by gender. Results indicate poor correspondence between parent and adolescent reports of aggression, which was most marked for females.

CONCLUSIONS

Aggressive behaviors are highly prevalent in depressed youths, with similar types and levels evident in males and females. Parents tend to under-report and may not be cognizant of aggressive behavior that occurs outside the home, particularly for females.

Integrating play therapy in the treatment of children with obsessive-compulsive disorder

While behavioral and psychopharmacological approaches are the most effective interventions for treating obsessive-compulsive disorder (OCD), psychodynamically oriented play therapy can enhance the treatment of children with this disorder. Play therapy techniques are useful in addressing treatment resistance, feelings of shame around OCD symptoms, negative self-concept, and issues of psychosocial adjustment. A case study illustrates this integrated approach to treatment.

Psychological and social determinants of women's decisions to undergo genetic counseling and testing for breast cancer

This study examined the demand for breast cancer genetic testing and counseling among Canadian women diagnosed with breast cancer under the age of 50, together with some of the factors predicting both their intentions to be tested and the degree to which they act on their intentions. Participants were 110 women under the age of 50 and comprised of two groups: 1) women diagnosed with breast cancer (BC, n = 60): and 2) an index group of unaffected women from the general population (GP, n = 50). All participants completed a survey that addressed family history of breast and other cancers, demographic variables, knowledge and attitudes about breast cancer, and genetic testing. Members of the BC group were offered genetic counseling and testing for BRCA1 and BRCA2 free of charge. Overall, 60% of participants indicated they would like the test, and 40% either did not want it or were uncertain. Seventy-two percent of women in the BC group wanted to be tested. Of these, only 49% had actually contacted the genetic counselor about testing at follow-up 3-15 months later. Intention to be tested was associated with presence of breast cancer, greater perceived benefits of testing, fewer perceived 'costs' of testing, and higher levels of concern about the risk of relatives developing breast cancer. Actual arranging to meet with the genetic counselor among women in the BC group was associated with fewer perceived costs of having the test. Results suggest a moderate level of interest in gene testing, though intention to be tested may not translate into actual uptake. Women who do choose to have the test may believe the potential 'costs' of using this new genetic technology to be relatively few. This has implications for genetic counselors in terms of providing balanced and complete information to women considering genetic testing for breast cancer susceptibility.

Glycyl-tRNA synthetase from Thermus thermophilus--wide structural divergence with other prokaryotic glycyl-tRNA synthetases and functional inter-relation with prokaryotic and eukaryotic glycylation systems

The tRNA glycylation system is amongst the most complex aminoacylation systems since neither the oligomeric structure of the enzymes nor the discriminator base in tRNAs are conserved in the phylae. To understand better this structural diversity and its functional consequences, the prokaryotic glycylation system from Thermus thermophilus, an extreme thermophile, was investigated and its structural and functional inter-relations with those of other origins analyzed. Alignments of the protein sequence of the dimeric thermophilic glycyl-tRNA synthetase (Gly-tRNA synthetase) derived from its gene with sequences of other dimeric Gly-tRNA synthetases revealed an atypical character of motif 1 in all these class 2 synthetases. Interestingly, the sequence of the prokaryotic thermophilic enzyme resembles eukaryotic and archaebacterial Gly-tRNA synthetases, which are all dimeric, and diverges drastically from the tetrameric enzymes from other prokaryotes. Cross aminoacylations with tRNAs and synthetases of different origins provided information about functional interrelations between the glycylation systems. Efficient glycylations involving partners from T. thermophilus and Escherichia coli showed conservation of the recognition process in prokaryotes despite strong structural variations of the synthetases. However, Gly-tRNA synthetase from T. thermophilus acylates eukaryotic tRNA(Gly) while the charging ability of the E. coli enzyme is restricted to prokaryotic tRNA(Gly). A similar behaviour is found in eukaryotic systems where the restricted species specificity for tRNA glycylation of mammalian Gly-tRNA synthetase contrasts with the relaxed specificity of the yeast enzyme. The consensus sequence of the tRNAs charged by the various Gly-tRNA synthetases reveals conservation of only G1-C72 in the acceptor arm, C35 and C36 in the anticodon, and the (G10-Y25)-G45 triplet involved in tRNA folding. Conservation of these nucleotides indicates their key role in glycylation and suggests that they were part of the ancestral glycine identity set. These features are discussed in the context of the phylogenic connections between prokaryotes, eukaryotes, and archaebacteria, and of the particular place of T. thermophilus in this phylogeny.

A role for histamine and substance P in immediate allergic responses in guinea pig airways: characterization of MDL 108,207DA, a dual H1/NK-1 receptor antagonist

BACKGROUND

Histamine is a critical mediator of immediate hypersensitivity reactions. Sensory neuropeptides, such as substance P (SP), may also contribute to acute inflammatory responses. A compound which antagonizes both H1 and NK-1 receptors, such as MDL 108,207DA, may present a significant therapeutic advantage over pure antihistamines.

METHODS

The binding affinity of MDL 108,207DA for H1 and NK-1 receptors was evaluated and its potency of antagonism evaluated in vitro. The in vivo antagonism of SP- or histamine-induced microvascular leakage in guinea pig airways was examined. A role for these mediators in antigen-induced microvascular leakage in ovalbumin-sensitized guinea pig airways was examined using MDL 108,207DA as well as the NK-1-selective antagonist FK888 and the H1-selective antagonist pyrilamine alone or in combination.

RESULTS

The affinity of MDL 108,207DA for H1 and NK-1 receptors is similar to that of receptor-selective antagonists. The compound inhibits both receptors in vitro and in vivo with comparable potencies for each. The efficacy of FK888 in combination with pyrilamine and MDL 108,207DA on antigen-induced microvascular leakage in sensitized guinea pig airways supports a role for both SP and histamine in early allergic responses.

CONCLUSION

The contribution of both SP and histamine to immediate hypersensitivity reactions supports the utility of NK-1 and H1 receptor antagonist therapy. MDL 108,207DA incorporates both activities into the same compound and, as a result, may be useful in the treatment of allergic diseases.

Lung cancer practice guidelines: lessons learned and issues addressed by the Ontario Lung Cancer Disease Site Group

PURPOSE

The primary objective was to identify the lessons learned and issues addressed by the Disease Site Group (DSG) developing guidelines on lung cancer for practitioners in the province of Ontario.

METHODS

The minutes of the Ontario Lung Cancer Disease Site Group (LCDSG) and the meeting notes of a medical sociologist who attended all LCDSG meetings were reviewed to identify the disease-specific and generic issues addressed by the LCDSG during guideline development.

RESULTS AND CONCLUSION

The Ontario LCDSG has completed three practice guidelines and has five evidence-based recommendations (EBRs) in production. Topics for guideline development were selected on the basis of known practice variability (eg, advanced-stage non-small-cell lung cancer [NSCLC]); the size of the patient population that could potentially be affected by the guideline; results of phase II trials of new and potentially expensive agents (vinorelbine, paclitaxel, and docetaxel); and randomized controlled clinical trials that support new practice standards (combined modality therapy for unresectable stage III NSCLC). The wording of each EBR reflects the strength and quality of the evidence in support of the treatment option, the primary outcome(s), and the individual physician and discipline values concerning treatment outcomes in the absence of known patient values.

Phase II study of a one hour paclitaxel infusion in combination with carboplatin for advanced non-small cell lung cancer

PURPOSE

To determine the activity, toxicity, and optimal dose of paclitaxel when given by one hour infusion combined with carboplatin in advanced non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Thirty-seven previously untreated patients with stage IIIB or IV NSCLC were enrolled. Paclitaxel was administered by one hour infusion at a dose of 175 mg/m2 for the first cycle, and was escalated up to 255 mg/m2 over successive cycles if tolerated. In the absence of toxicity, the carboplatin dose was kept constant at an area under the concentration-time curve (AUC) of 6. Cycles were repeated at 3-week intervals until progression or intolerable toxicity occurred.

RESULTS

Thirty-six patients were evaluable for toxicity and survival, and thirty-five for responses. The partial response rate was 10 of 35 (29%) and there were no complete responses. The median duration of response was 4.8 months (range 0.5-11.7 months). The median survival duration was 6.5 months, and 1 year survival was 31%. The mean paclitaxel dose was 188 mg/m2. Treatment was generally well tolerated. Four patients (11%) had febrile neutropenia. Five patients (14%) had grade 3 neuropathy, and 4 (11%) had grade 3 nausea and vomiting. Minor toxicities included alopecia, myalgias, arthralgias and stomatitis.

CONCLUSIONS

Paclitaxel and carboplatin is a well-tolerated regimen that can safely be given by a one hour paclitaxel infusion. The modest response rate observed in this study may be due to either the low dose-intensity of paclitaxel or the short infusion duration. Further trials to optimize the relative doses of paclitaxel and carboplatin are needed.

Ribonucleotide reductase--structural studies of a radical enzyme

Ribonucleotide reductase contains a stable organic free radical essential for its activity located on a tyrosine residue in the small subunit of the enzyme called R2. The substrate binding site is, however, found in the catalytic subunit called R1. A long-range protein-mediated radical transfer pathway appears to be responsible for the delivery of the radical from the tyrosine in R2 to the substrate on R1. The active site is located deep inside the protein in a very stable beta/alpha-barrel structure and a hydrogen bonded system leads from the surface to Cys439 at the active site which is in excellent position to remove a hydrogen from the 3' of the ribose of a bound substrate nucleotide.

Paclitaxel plus hydroxyurea as second line therapy for non-small cell lung cancer

We tested paclitaxel (Taxol) and low dose hydroxyurea as second line therapy in 30 patients with non-small cell lung cancer since both drugs are active against non-small cell lung cancer in other settings, and since hydroxyurea may reverse chemotherapy resistance by disrupting double minute chromosomes. Hydroxyurea 500 mg was given orally each Monday, Wednesday, Friday starting 1 week before paclitaxel, and continuing until removal from study. Paclitaxel 135 mg/m2 was given i.v. over > or = 1 h every 3 weeks with dexamethasone, diphenhydramine, and ranitidine. Patients could have paclitaxel doses escalated to 175 mg/m2 in course 2 and to 200 mg/m2 in course 3, where tolerated. Sixteen males and 14 females were treated. All patients had previously received a single cisplatin-based chemotherapy regimen and 23 had previously received radiotherapy. Twelve patients had adenocarcinomas, six had squamous cell carcinomas, and 12 had large cell carcinomas. Eight patients had Stage IIIb cancers and 22 had Stage IV. Paclitaxel doses were 135 mg/m2 in 56 courses, 175 mg/m2 in 24, and 200 mg/m2 in 15. Treatment was well tolerated. Median granulocyte nadirs were 2.5 (x 10(9)/l) for paclitaxel 135 mg/m2, 1.8 for 175 mg/m2, and 1.3 for 200 mg/m2. No patient developed febrile neutropenia, and none required a dose reduction. Two patients had reversible anaphylaxis. Other toxicities were quite tolerable. They included fatigue, myalgias, dizziness, paresthesias, diarrhea, alopecia, mucositis, flushing, headache, swollen red hands, and anxiety. One patient had a partial remission and 15 had stable disease (including six with minor responses). Median survival was 20 (95% CI, 12-34) weeks, with 19% of patients remaining alive at 1 year from initiation of treatment. This is a well-tolerated regimen with modest activity as second line chemotherapy for patients with non-small cell lung cancer previously treated with cisplatin regimens. Higher doses would be feasible and other strategies are now being explored.

Structural comparison of two strains of foot-and-mouth disease virus subtype O1 and a laboratory antigenic variant, G67

BACKGROUND

Foot-and-mouth disease viruses (FMDVs) are members of the picornavirus family and cause an economically important disease of cloven-hoofed animals. To understand the structural basis of antigenic variation in FMDV, we have determined the structures of two viruses closely related to strain O1BFS whose structure is known.

RESULTS

The two new structure are, like O1BFS, both serotype O viruses. The first, O1 Kaüfbeuren (O1K), is a field isolate dating from an outbreak of FMD in Europe in the 1960s. The second, called G67, is a quadruple mutant of O1K, generated in the laboratory, that bears point mutations conferring resistance to neutralizing by monoclonal antibodies, specific for each of the four major antigenic sites defined previously. The availability of the three related virus structures permits a detailed analysis of the way amino acid substitutions influence antigenicity. Structural changes are seen to be limited, in general, to the substituted side chain. For example, the GH loop of VP1, a highly antigenic and mobile protuberance which becomes ordered only under reducing conditions, was essentially indistinguishable in the three viruses despite the accumulation of up to four changes within its 15-residue sequence. At one of the other antigenic sites, however, changes between the two field strains did perturb both side-chain and main-chain structures in the vicinity.

CONCLUSIONS

The conservation of conformation of the GH loop of VP1 adds to the evidence implicating an integrin as the cellular receptor for FMDV, since this loop contains a conserved RGD (Arg-Gly-Asp) sequence structurally similar to the same tripeptide in some other integrin-binding proteins. Structural changes required for the virus to escape neutralization by monoclonal antibodies are generally small. The more extensive type of structural change exhibited by the field isolates probably reflects differing selective pressures operating in vivo and in vitro.

Mixed germ cell malignancy of the ovary concurrent with pregnancy

BACKGROUND

A rare malignant germ cell tumor of the ovary during pregnancy was detected by screening of maternal serum alpha-fetoprotein (MSAFP). Treatment of this uncommon tumor during pregnancy incorporated combination chemotherapy including etoposide.

CASE

An 18-year-old primiparous woman undergoing antenatal genetic screening was found to have an extremely elevated MSAFP of 477.8 IU/mL, or 12.46 multiples of the median. Oophorectomy and staging laparotomy at 20.5 weeks' gestation resulted in the diagnosis of mixed germ cell tumor of the ovary, with both endodermal sinus tumor and grade 3 immature teratoma. The patient received three courses of cis-platinum, etoposide, and bleomycin. Maternal serum AFP titers had returned to normal pregnancy levels by the start of the second course. A healthy female infant was delivered at 39 weeks' gestation following induction of labor for pregnancy-induced hypertension.

CONCLUSION

Elevated MSAFP levels may be a presenting sign of malignant ovarian germ cell neoplasms. This report describes both surgical and chemotherapeutic treatment of a germ cell malignancy during pregnancy, with delivery at term. To date, major fetal toxicity from chemotherapy has not been identified.

Addition of pentoxifylline plus nifedipine to chemotherapy in patients with cisplatin-resistant cancers of the lung and other sites

Eight evaluable patients with cisplatin-resistant non-small cell lung cancer (6 patients), small cell lung cancer (1 patient), or both breast and ovarian cancer (1 patient) were entered on a study to determine whether the addition of nifedipine plus pentoxifylline to cisplatin-based chemotherapy would result in increased chemotherapy efficacy. No patient responded to treatment. Myelosuppression may have been augmented by the nifedipine and pentoxifylline (median granulocyte nadir, 0.3 x 10(9)/L). Two patients developed febrile neutropenia. Nifedipine and pentoxifylline had to be stopped in two evaluable patients due to hypotension, and three additional inevaluable patients withdrew from the study due to nifedipine-pentoxifylline toxicity before receiving their chemotherapy. There was no indication that other types of chemotherapy toxicity were increased by the addition of nifedipine and pentoxifylline. A major problem with the strategy followed in this protocol was that patients whose tumors had failed to respond to cisplatin-based regimens were often too ill to tolerate additional cisplatin, particularly when accompanied by nifedipine-associated hypotension.

The structure of an immunodominant loop on foot and mouth disease virus, serotype O1, determined under reducing conditions

Residues 136-159 of VPI of foot and mouth disease virus (FMDV) comprise the G-H loop of the protein and form a prominent feature on the surface of virus particles. This sequence contains an immunodominant neutralizing epitope, which can be mimicked with synthetic peptides, and includes an Arg, Gly, Asp motif which has been implicated in the binding of the virus to cellular receptors. Crystallographic analysis of native virus particles failed to resolve the structure of this region due to its disordered state. However, reduction of a disulphide bond between cysteine residues 134 of VP1 and 130 of VP2 caused the G-H loop to collapse onto the surface of the virus particle and allowed its conformation to be determined.

VP-16, ifosfamide and cisplatin (VIP) for extensive small cell lung cancer

Thirty-seven extensive disease SCLC patients were treated with ifosfamide 1.0 g/m2 (maximum 1.75 g), VP-16 (etoposide) 75 mg/m2 and cisplatin 20 mg/m2 (VIP) daily for 5 days in hospital. Mesna was given as a continuous infusion until 12 h after the last ifosfamide dose. Treatment was reduced to 4 days after the first 8 patients experienced serious myelotoxicity. 30 patients were evaluable for response. 8 (27%) achieved a complete response and 60% had a partial response. The median duration of response was 23 weeks. The median survival of all 37 patients was 41 weeks, and 47 weeks for the 30 evaluable patients. Fifty per cent and 26% of the evaluable treatment courses were associated with grade 4 and 3 granulocytopenia, respectively. There were eight febrile events including four treatment-related deaths from sepsis on the 5-day regimen. Although the response to VIP was generally rapid, the proportion achieving complete response (27% of evaluable patients) and the median survival is similar to standard chemotherapy regimens which are less toxic and less complex to administer.

Inhibition of HIV-1 replication by daunorubicin

Members of the anthracycline family of drugs such as daunorubicin (DNR) are currently being employed in cancer therapy, treatment of Kaposi's sarcoma and lymphomas in HIV-1 infected patients. These drugs may have an anti-viral activity against HIV-1. Experiments conducted on U937 (a promonocytic cell line), peripheral blood monocytes (without T cells) and infected with HIV-1 showed anti-viral activity at nanogram/ml concentrations, without affecting cell proliferation and cell viability. Treatment of Hut 78 cells (a T cell line) with DNR was not as effective in inhibiting HIV-1 replication when compared to the anti-HIV activity in cells of the monocyte lineage.

Structure of a major immunogenic site on foot-and-mouth disease virus

Attachment of foot-and-mouth disease virus (FMDV) to its cellular receptor involves a long and highly antigenic loop containing the conserved sequence, Arg-Gly-Asp, a motif known to be a recognition element in many integrin-dependent cell adhesion processes. In our original crystal structure of FMDV the Arg-Gly-Asp-containing loop ('the loop'), located between beta-strands G and H of capsid protein VP1, was disordered and hence essentially invisible. We previously surmised that its disorder is enhanced by a disulphide bond linking the base of the loop (Cys 134) to Cys 130 of VP2 (ref. 8). We report here the crystal structure of the virus in which this disulphide is reduced. Reduced virus retains infectivity and serological experiments suggest that some of the loop's internal structure is conserved. But here its structure has become sufficiently ordered to allow us to describe an unambiguous conformation, which we relate to some key biological properties of the virus.