Laparoscopic large hiatus hernia repair with mesh reinforcement versus suture cruroplasty alone: a systematic review and meta-analysis

BACKGROUND

To compare the difference in outcomes in laparoscopic large hiatus hernia (LHH) repair using suture-based and mesh-based repair techniques.

METHODS

A systematic search of articles was conducted in PubMed, Medline and Embase using the PRISMA guidelines. Studies comparing recurrences and reoperations in those patients with large hiatal hernia repair (> 30% stomach in the chest, > 5 cm hiatal defect, hiatal surface area > 10 cm²) who had mesh vs no mesh were assessed quantitatively. The impact of mesh on significant intraoperative/postoperative surgical complications was qualitatively assessed.

RESULTS

Pooled data included six randomized controlled trials and thirteen observational studies with 1670 patients (824 with no mesh, 846 with mesh). There was a significant reduction in the total recurrence rate with mesh (OR 0.44, 95% CI 0.25-0.80, p = 0.007). Mesh use did not cause significant reduction in recurrences > 2 cm (OR 0.94, 95% CI 0.52-1.67, p = 0.83) or in reoperation rates (OR 0.64, 95% CI 0.39-1.07, p = 0.09). None of the specific meshes assessed were found to be superior in the reduction of recurrence or reoperation rates. Cases of mesh erosion with eventual foregut resection were noted and were associated with synthetic meshes only.

CONCLUSION

Mesh reinforcement seemed protective against total recurrence in LHH although this has to be interpreted with caution given the level of heterogeneity introduced by the inclusion of observational studies in the analysis. There was no significant reduction in large recurrences (> 2 cm) or reoperation rate. If the synthetic mesh is to be used patients need to be informed of the risk of mesh erosion.

Early Diagnosis and Lung Cancer Screening

Lung cancer remains the most significant cause of cancer death, accounting for about 20% of all cancer-related mortality. A significant reason for this is delayed diagnosis, either due to lack of symptoms in early-stage disease or presentation with non-specific symptoms common with a broad range of alternative diagnoses. More is needed in terms of increasing public awareness, providing adequate healthcare professional education and implementing clinical pathways that improve the earlier diagnosis of symptomatic lung cancer. Low-dose computed tomography screening of high-risk, asymptomatic populations has been shown to reduce lung cancer mortality, with focus now shifting towards how best to implement lung cancer screening on a wider scale in a safe, efficient and cost-effective manner. For maximum benefit, efforts must be made to optimise uptake, especially among high-risk populations with significant socioeconomic deprivation, as well as successfully incorporate tobacco-dependency treatment. Quality assured programme management will be critical to minimising screening-related harms and adequately managing incidental findings. By undertaking the above, there can be optimism that lung cancer outcomes can be improved significantly in the near future.

The influence of anastomotic techniques on postoperative anastomotic complications: Results of the Oesophago-Gastric Anastomosis Audit

BACKGROUND

The optimal anastomotic techniques in esophagectomy to minimize rates of anastomotic leakage and conduit necrosis are not known. The aim of this study was to assess whether the anastomotic technique was associated with anastomotic failure after esophagectomy in the international Oesophago-Gastric Anastomosis Audit cohort.

METHODS

This prospective observational multicenter cohort study included patients undergoing esophagectomy for esophageal cancer over 9 months during 2018. The primary exposure was the anastomotic technique, classified as handsewn, linear stapled, or circular stapled. The primary outcome was anastomotic failure, namely a composite of anastomotic leakage and conduit necrosis, as defined by the Esophageal Complications Consensus Group. Multivariable logistic regression modeling was used to identify the association between anastomotic techniques and anastomotic failure, after adjustment for confounders.

RESULTS

Of the 2238 esophagectomies, the anastomosis was handsewn in 27.1%, linear stapled in 21.0%, and circular stapled in 51.9%. Anastomotic techniques differed significantly by the anastomosis sites (P < .001), with the majority of neck anastomoses being handsewn (69.9%), whereas most chest anastomoses were stapled (66.3% circular stapled and 19.3% linear stapled). Rates of anastomotic failure differed significantly among the anastomotic techniques (P < .001), from 19.3% in handsewn anastomoses, to 14.0% in linear stapled anastomoses, and 12.1% in circular stapled anastomoses. This effect remained significant after adjustment for confounding factors on multivariable analysis, with an odds ratio of 0.63 (95% CI, 0.46-0.86; P = .004) for circular stapled versus handsewn anastomosis. However, subgroup analysis by anastomosis site suggested that this effect was predominantly present in neck anastomoses, with anastomotic failure rates of 23.2% versus 14.6% versus 5.9% for handsewn versus linear stapled anastomoses versus circular stapled neck anastomoses, compared with 13.7% versus 13.8% versus 12.2% for chest anastomoses.

CONCLUSIONS

Handsewn anastomoses appear to be independently associated with higher rates of anastomotic failure compared with stapled anastomoses. However, this effect seems to be largely confined to neck anastomoses, with minimal differences between techniques observed for chest anastomoses. Further research into standardization of anastomotic approach and techniques may further improve outcomes.

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

Methods

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

Results

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P &lt; 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P &lt; 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

Conclusion

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

METHODS

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

RESULTS

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter 'no major postoperative complication' had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

CONCLUSION

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND

The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting.

METHODS

Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups.

RESULTS

Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005).

CONCLUSION

Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery.

V3-Loop genotypes do not predict maraviroc susceptibility of CCR5-tropic virus or clinical response through week 48 in HIV-1-infected, treatment-experienced persons receiving optimized background regimens

Viruses from 15 of 35 maraviroc-treated participants with virologic failure and CCR5-tropic (R5) virus in the MOTIVATE studies at Week 24 had reduced maraviroc susceptibility. On-treatment amino acid changes were observed in the viral envelope glycoprotein 120 third variable (V3)-loop stems and tips and differed between viruses. No amino acid change reliably predicted reduced susceptibility, indicating that resistance was genetic context-dependent. Through Week 24, poor adherence was associated with maraviroc-susceptible virologic failure, whereas reduced maraviroc susceptibility was associated with suboptimal background regimen activity, highlighting the importance of overall regimen activity and good adherence. Predictive values of pretreatment V3-loop sequences containing these Week 24 mutations or other variants present at >3% in pretreatment viruses of participants with virologic failure at Week 48 were retrospectively assessed. Week 48 clinical outcomes were evaluated for correlates with pretreatment V3-loop CCR5-tropic sequences from 704 participants (366 responders; 338 virologic failures [83 with R5 virus with maraviroc susceptibility assessment]). Seventy-five amino acid variants with >3% prevalence were identified among 23 V3-loop residues. Previously identified variants associated with resistance in individual isolates were represented, but none were associated reliably with virologic failure alone or in combination. Univariate analysis showed virologic-failure associations with variants 4L, 11R, and 19S (P < 0.05). However, 11R is a marker for CXCR4 tropism, whereas neither 4L nor 19S was reliably associated with reduced maraviroc susceptibility in R5 failure. These findings from a large study of V3-loop sequences confirm lack of correlation between V3-loop genotype and clinical outcome in participants treated with maraviroc.Clinical trial registration numbers (ClinicalTrials.gov): NCT00098306 and NCT00098722.

Effectiveness of Adaptive Silverware on Active Range of Motion in Individuals With Rheumatoid Arthritis

Date Presented Accepted for AOTA INSPIRE 2021 but unable to be presented due to online event limitations.

The purpose of this study was to quantify active range of motion (ROM) required for individuals with rheumatoid arthritis (RA) using built-up spoons with electrogoniometry. Statistical analysis provided quantitative evidence supporting our hypothesis that using a built-up handle requires less active ROM for grasp. Clinical implications suggest built-up handles may be used for people with other conditions with limited hand and wrist ROM, not just RA, increasing participation and independence in daily activiti

Primary Author and Speaker: Susan McDonald

Additional Authors and Speakers: David Levine, Hensley Barnes, Anna Cornett, Caroline Craig, Sally Langager, Lauren Yeager, and Michael Britt

Mortality from esophagectomy for esophageal cancer across low, middle, and high-income countries: An international cohort study

BACKGROUND

No evidence currently exists characterising global outcomes following major cancer surgery, including esophageal cancer. Therefore, this study aimed to characterise impact of high income countries (HIC) versus low and middle income countries (LMIC) on the outcomes following esophagectomy for esophageal cancer.

METHOD

This international multi-center prospective study across 137 hospitals in 41 countries included patients who underwent an esophagectomy for esophageal cancer, with 90-day follow-up. The main explanatory variable was country income, defined according to the World Bank Data classification. The primary outcome was 90-day postoperative mortality, and secondary outcomes were composite leaks (anastomotic leak or conduit necrosis) and major complications (Clavien-Dindo Grade III - V). Multivariable generalized estimating equation models were used to produce adjusted odds ratios (ORs) and 95% confidence intervals (CI95%).

RESULTS

Between April 2018 to December 2018, 2247 patients were included. Patients from HIC were more significantly older, with higher ASA grade, and more advanced tumors. Patients from LMIC had almost three-fold increase in 90-day mortality, compared to HIC (9.4% vs 3.7%, p < 0.001). On adjusted analysis, LMIC were independently associated with higher 90-day mortality (OR: 2.31, CI95%: 1.17-4.55, p = 0.015). However, LMIC were not independently associated with higher rates of anastomotic leaks (OR: 1.06, CI95%: 0.57-1.99, p = 0.9) or major complications (OR: 0.85, CI95%: 0.54-1.32, p = 0.5), compared to HIC.

CONCLUSION

Resections in LMIC were independently associated with higher 90-day postoperative mortality, likely reflecting a failure to rescue of these patients following esophagectomy, despite similar composite anastomotic leaks and major complication rates to HIC. These findings warrant further research, to identify potential issues and solutions to improve global outcomes following esophagectomy for cancer.

Comparison of short-term outcomes from the International Oesophago-Gastric Anastomosis Audit (OGAA), the Esophagectomy Complications Consensus Group (ECCG), and the Dutch Upper Gastrointestinal Cancer Audit (DUCA)

BACKGROUND

The Esophagectomy Complications Consensus Group (ECCG) and the Dutch Upper Gastrointestinal Cancer Audit (DUCA) have set standards in reporting outcomes after oesophagectomy. Reporting outcomes from selected high-volume centres or centralized national cancer programmes may not, however, be reflective of the true global prevalence of complications. This study aimed to compare complication rates after oesophagectomy from these existing sources with those of an unselected international cohort from the Oesophago-Gastric Anastomosis Audit (OGAA).

METHODS

The OGAA was a prospective multicentre cohort study coordinated by the West Midlands Research Collaborative, and included patients undergoing oesophagectomy for oesophageal cancer between April and December 2018, with 90 days of follow-up.

RESULTS

The OGAA study included 2247 oesophagectomies across 137 hospitals in 41 countries. Comparisons with the ECCG and DUCA found differences in baseline demographics between the three cohorts, including age, ASA grade, and rates of chronic pulmonary disease. The OGAA had the lowest rates of neoadjuvant treatment (OGAA 75.1 per cent, ECCG 78.9 per cent, DUCA 93.5 per cent; P < 0.001). DUCA exhibited the highest rates of minimally invasive surgery (OGAA 57.2 per cent, ECCG 47.9 per cent, DUCA 85.8 per cent; P < 0.001). Overall complication rates were similar in the three cohorts (OGAA 63.6 per cent, ECCG 59.0 per cent, DUCA 62.2 per cent), with no statistically significant difference in Clavien-Dindo grades (P = 0.752). However, a significant difference in 30-day mortality was observed, with DUCA reporting the lowest rate (OGAA 3.2 per cent, ECCG 2.4 per cent, DUCA 1.7 per cent; P = 0.013).

CONCLUSION

Despite differences in rates of co-morbidities, oncological treatment strategies, and access to minimal-access surgery, overall complication rates were similar in the three cohorts.

Highly prevalent Russian HIV-1 V3-loop sequence variants are susceptible to maraviroc

INTRODUCTION

Maraviroc inhibits CCR5-tropic HIV-1 across different subtypes in vitro and has demonstrated efficacy in clinical trials. V3-loop amino acid variants observed in individual maraviroc-resistant viruses have not been found to be predictive of reduced susceptibility. Sequence-database searches have demonstrated that approximately 7.3% of viruses naturally encode these variants, raising concerns regarding potential pre-existing resistance. A study from Russia reported that combinations of these same amino acids are present in the V3 loops of the Russian variant subtype A (IDU-A, now A6) with a much greater prevalence (range: 74.4%-92.3%) depending on the combination. However, these studies and database searches did not include phenotypic evaluation.

METHODS

Sixteen Russian HIV-1 isolates (including sub-subtype A6 viruses) were assessed for V3 loop sequence and phenotypic susceptibility to maraviroc.

RESULTS

All 12 of the A6 viruses and 2/4 subtype B isolates encoded V3-loop variants that have previously been identified in individual virus isolates with reduced susceptibility to maraviroc. However, despite the prevalence of these V3-loop amino acid variants among the tested viruses, phenotypic sensitivity to maraviroc was observed in all instances. Similarly, reduced susceptibility to maraviroc was not found in virus from participants who experienced virologic failure in a clinical study of maraviroc in Russia (A4001101, [NCT01275625]).

DISCUSSION

Altogether, these data confirm that the presence of individual or combinations of V3-loop amino acid residues in sub-subtype A6 viruses alone does not predict natural resistance to maraviroc and that V3-loop genotype analysis of R5 virus prior to treatment is not helpful in predicting clinical outcome.

General practitioners' perceptions of compassionate communities: a qualitative study

Background

General Practitioners (GPs) face challenges when providing palliative care, including an ageing, multimorbid population, and falling GP numbers. A ‘public health palliative care’ approach, defined as “working with communities to improve people’s experience of death, dying and bereavement”, is gaining momentum. ‘Compassionate communities’ is one example, with a focus on linking professional health carers with supportive community networks. Primary care is central to the approach, which has been incorporated into United Kingdom GP palliative care guidance. No research to date, however, has investigated GP perspectives of these approaches. Our aim, therefore, was to explore GP perceptions of a public health approach to palliative care, and compassionate communities.

Methods

GPs working in the United Kingdom were recruited through university teaching and research networks using snowball sampling. Purposive sampling ensured wide representation of gender, level of experience and practice populations. Semi-structured, digitally audio-recorded interviews were conducted with nine GPs. Interviews were transcribed verbatim, and thematic analysis was undertaken, informed by a qualitative descriptive methodology. Interviews continued until data saturation was reached.

Results

Most participants were unfamiliar with the term ‘compassionate communities’, but recognised examples within their practice. Three major themes with seven subthemes were identified: 1) Perceived potential of compassionate communities, including: ‘maximising use of existing community services’; ‘influencing health outside of healthcare’; and ‘combatting taboo’, 2) Perceived challenges of compassionate communities, including: ‘patient safety’; ‘limited capacity of the community’; ‘limited capacity of general practice’, and ‘applicability of public health to palliative care’, and 3) The role of the GP in compassionate communities.

Conclusions

GPs recognised the importance of the wider community in caring for palliative care patients, however most were unfamiliar with the compassionate community approach. Participants held differing views regarding the application of the model, and the position of general practice within this. Further research into the approach’s practical implementation, and exploring the views of other key stakeholders, would help establish the feasibility of compassionate communities in practice, and guide its future application.

The utility of patient reported data in a gynecologic oncology clinic

BACKGROUND

Measuring QoL is essential to the field of gynecologic oncology but there seems to be limited standardized data regarding collecting QoL assessments throughout a patient's cancer treatment especially in non-clinical trial patients. The aim of this study is to explore patient characteristics that may be associated with poor quality of life (QoL) in women with gynecologic cancers at two University of Arizona Cancer Center (UACC) sites.

METHODS

A cross-sectional survey was conducted among English speaking women with gynecologic malignancies at the University of Arizona Cancer Centers in Phoenix and Tucson from April 2012 to July 2015. The survey was a paper packet of questions that was distributed to cancer patients at the time of their clinic visit. The packet contained questions on demographic information, treatment, lifestyle characteristics, pelvic pain and Health-related quality of life (HRQoL). Measures included the generic and cancer-specific scores on the Functional Assessment of Cancer Therapy-General (FACT-G) and the Female Genitourinary Pain Index (GUPI). The total scores and subdomains were compared with descriptive variables (age, body mass index (BMI), diet, exercise, disease status, treatment and support group attendance) using Cronbach alpha (α), Spearman rank correlations (ρ), and Holm's Bonferroni method.

RESULTS

One-hundred and forty-nine women completed the survey; 55% (N = 81) were older than 60 years, 38% (N = 45) were obese (BMI > 30), 46% (N = 66) exercised daily, and 84% (N = 111) ate one or more daily serving of fruit and vegetables. Women in remission, those who exercised daily and ate fruits/vegetables were less likely to have their symptoms impact their QoL. Younger women were more likely to report genitourinary issues (p = - 0.22) and overall problems with QoL (p = - 0.29) than older women. Among FACT-G support group responses, we found those that did not attend support groups had a significantly higher emotional wellbeing (p = 0.05).

CONCLUSIONS

This study identified potential areas of clinical focus, which aid in understanding our approach to caring for gynecologic cancer patients and improvement of their HRQoL. We identified that age, pelvic pain, and lifestyle characteristics have indicators to poor QoL in women with gynecologic cancers. In this population, younger women and those with pelvic pain complaints, poor diet and exercise habits should be targeted early for supportive care interventions to improve QoL throughout both treatment and survivorship.

Evaluation of corn hybrids expressing Cry1F, cry1A.105, Cry2Ab2, Cry34Ab1/Cry35Ab1, and Cry3Bb1 against southern United States insect pests

Studies were conducted across the southern United States to characterize the efficacy of multiple Bacillus thuringiensis (Bt) events in a field corn, Zea mays L., hybrid for control of common lepidopteran and coleopteran pests. Cry1F protein in event TC1507 and Cry1A.105 + Cry2Ab2 proteins in event MON 89034 were evaluated against pests infesting corn on above-ground plant tissue including foliage, stalks, and ears. Cry34Ab1/Cry35Ab1 proteins in event DAS-59122-7 and Cry3Bb1 in event MON 88017 were evaluated against the larvae of Mexican corn rootworm, Diabrotica virgifera zeae Krysan and Smith, which occur below-ground. Field corn hybrids containing Cry1F, Cry1A.105 + Cry2Ab2, Cry34Ab1/Cry35Ab1, and Cry3Bb1 insecticidal proteins (SmartStax) consistently demonstrated reductions in plant injury and/or reduced larval survivorship as compared with a non-Bt field corn hybrid. Efficacy provided by a field corn hybrid with multiple Bt proteins was statistically equal to or significantly better than corn hybrids containing a single event active against target pests. Single event field corn hybrids provided very high levels of control of southwestern corn borer, Diatraea grandiosella (Dyar), lesser cornstalk borer, Elasmopalpus lignosellus (Zeller), and fall armyworm, Spodoptera frugiperda (J.E. Smith), and were not significantly different than field corn hybrids with multiple events. Significant increases in efficacy were observed for a field corn hybrid with multiple Bt events for sugarcane borer, Diatraea saccharalis (F.), beet armyworm, Spodoptera exigua (Hübner), corn earworm, Helicoverpa zea (Boddie), and Mexican corn rootworm. Utilization of field corn hybrids containing multiple Bt events provides a means for managing insect resistance to Bt proteins and reduces non-Bt corn refuge requirements.

The innate immune response, clinical outcomes, and ex vivo HCV antiviral efficacy of a TLR7 agonist (PF-4878691)

Hepatitis C virus (HCV) infection is an issue of global concern, and studies are ongoing to identify new therapies that are both effective and safe. PF-4878691 is a Toll-like receptor 7 (TLR7) agonist modeled so as to dissociate its antiviral activities from its inflammatory activities. In a proof-of-mechanism study in healthy volunteers who received doses of 3, 6, and 9 mg of PF-4878691 twice a week for 2 weeks, PF-4878691 induced biomarkers of the immune and interferon (IFN) responses in a dose-dependent and dose-frequency-related manner. A novel finding was induction of TLR7 expression in vivo in response to PF-4878691, leading to an amplified biomarker response. A nonresponder at the 9-mg dose had a polymorphism in the IFN-α receptor 1 subunit (Val168Leu). Two subjects who had received 9-mg doses experienced serious adverse events (SAEs), characterized by flu-like symptoms, hypotension, and lymphopenia, leading to early termination of the study. TLR7 stimulation results in a pharmacologic response at levels commensurate with predicted antiviral efficacy, but these doses are associated with SAEs, raising concerns about the therapeutic window of this class of compounds for the treatment of HCV infection.

A self-regulating feed-forward circuit controlling C. elegans egg-laying behavior

BACKGROUND

Egg laying in Caenorhabditis elegans has been well studied at the genetic and behavioral levels. However, the neural basis of egg-laying behavior is still not well understood; in particular, the roles of specific neurons and the functional nature of the synaptic connections in the egg-laying circuit remain uncharacterized.

RESULTS

We have used in vivo neuroimaging and laser surgery to address these questions in intact, behaving animals. We have found that the HSN neurons play a central role in driving egg-laying behavior through direct excitation of the vulval muscles and VC motor neurons. The VC neurons play a dual role in the egg-laying circuit, exciting the vulval muscles while feedback-inhibiting the HSNs. Interestingly, the HSNs are active in the absence of synaptic input, suggesting that egg laying may be controlled through modulation of autonomous HSN activity. Indeed, body touch appears to inhibit egg laying, in part by interfering with HSN calcium oscillations.

CONCLUSIONS

The egg-laying motor circuit comprises a simple three-component system combining feed-forward excitation and feedback inhibition. This microcircuit motif is common in the C. elegans nervous system, as well as in the mammalian cortex; thus, understanding its functional properties in C. elegans may provide insight into its computational role in more complex brains.

GW274150 and GW273629 are potent and highly selective inhibitors of inducible nitric oxide synthase in vitro and in vivo

1 GW274150 ([2-[(1-iminoethyl) amino]ethyl]-L-homocysteine) and GW273629 (3-[[2-[(1-iminoethyl)amino]ethyl]sulphonyl]-L-alanine) are potent, time-dependent, highly selective inhibitors of human inducible nitric oxide synthase (iNOS) vs endothelial NOS (eNOS) (>100-fold) or neuronal NOS (nNOS) (>80-fold). GW274150 and GW273629 are arginine competitive, NADPH-dependent inhibitors of human iNOS with steady state K(d) values of <40 and <90 nM, respectively. 2 GW274150 and GW273629 inhibited intracellular iNOS in J774 cells in a time-dependent manner, reaching IC(50) values of 0.2+/-0.04 and 1.3+/-0.16 microM, respectively. They were also acutely selective in intact rat tissues: GW274150 was >260-fold and 219-fold selective for iNOS against eNOS and nNOS, respectively, while GW273629 was >150-fold and 365-fold selective for iNOS against eNOS and nNOS, respectively. 3 The pharmacokinetic profile of GW274150 was biphasic in healthy rats and mice with a terminal half-life of approximately 6 h. That of GW273629 was also biphasic in rats, producing a terminal half-life of approximately 3 h. In mice however, elimination of GW273629 appeared monophasic and more rapid (approximately 10 min). Both compounds show a high oral bioavailability (>90%) in rats and mice. 4 GW274150 was effective in inhibiting LPS-induced plasma NO(x) levels in mice with an ED(50) of 3.2+/-0.7 mg kg(-1) after 14 h intraperitoneally (i.p.) and 3.8+/-1.5 mg kg(-1) after 14 h when administered orally. GW273629 showed shorter-lived effects on plasma NO(x) and an ED(50) of 9+/-2 mg kg(-1) after 2 h when administered i.p. 5 The effects of GW274150 and GW273629 in vivo were consistent with high selectivity for iNOS, as these inhibitors were of low potency against nNOS in the rat cerebellum and did not cause significant effects on blood pressure in instrumented mice.

Is perception of upper body orientation based on the inertia tensor? Normogravity versus microgravity conditions

During lateral leg raising, a synergistic inclination of the supporting leg and trunk in the opposite direction to the leg movement is performed in order to preserve equilibrium. As first hypothesized by Pagano and Turvey (J Exp Psychol Hum Percept Perform, 1995, 21:1070-1087), the perception of limb orientation could be based on the orientation of the limb's inertia tensor. The purpose of this study was thus to explore whether the final upper body orientation (trunk inclination relative to vertical) depends on changes in the trunk inertia tensor. We imposed a loading condition, with total mass of 4 kg added to the subject's trunk in either a symmetrical or asymmetrical configuration. This changed the orientation of the trunk inertia tensor while keeping the total trunk mass constant. In order to separate any effects of the inertia tensor from the effects of gravitational torque, the experiment was carried out in normo- and microgravity. The results indicated that in normogravity the same final upper body orientation was maintained irrespective of the loading condition. In microgravity, regardless of loading conditions the same (but different from the normogravity) orientation of the upper body was achieved through different joint organizations: two joints (the hip and ankle joints of the supporting leg) in the asymmetrical loading condition, and one (hip) in the symmetrical loading condition. In order to determine whether the different orientations of the inertia tensor were perceived during the movement, the interjoint coordination was quantified by performing a principal components analysis (PCA) on the supporting and moving hips and on the supporting ankle joints. It was expected that different loading conditions would modify the principal component of the PCA. In normogravity, asymmetrical loading decreased the coupling between joints, while in microgravity a strong coupling was preserved whatever the loading condition. It was concluded that the trunk inertia tensor did not play a role during the lateral leg raising task because in spite of the absence of gravitational torque the final upper body orientation and the interjoint coupling were not influenced.

Eosinophilic granuloma. A different behaviour in children than in adults

Localised Langerhans-cell histiocytosis of bone (eosinophilic granuloma) is a benign tumour-like condition with a variable clinical course. Different forms of treatment have been reported to give satisfactory results. However, previous series all contain patients with a wide age range. Our aim was to investigate the effect of skeletal maturity on the rate of recurrence of isolated eosinophilic granuloma of bone excluding those arising in the spine. We followed up 32 patients with an isolated eosinophilic granuloma for a mean of five years; 17 were skeletally immature. No recurrences were noted in the skeletally immature group even after biopsy alone. By contrast, four of 13 skeletally mature patients had a recurrence and required further surgery. This suggests that eosinophilic granuloma has a low rate of recurrence in skeletally immature patients.

Eosinophilic granuloma

Localised Langerhans-cell histiocytosis of bone (eosinophilic granuloma) is a benign tumour-like condition with a variable clinical course. Different forms of treatment have been reported to give satisfactory results. However, previous series all contain patients with a wide age range. Our aim was to investigate the effect of skeletal maturity on the rate of recurrence of isolated eosinophilic granuloma of bone excluding those arising in the spine.

We followed up 32 patients with an isolated eosinophilic granuloma for a mean of five years; 17 were skeletally immature. No recurrences were noted in the skeletally immature group even after biopsy alone. By contrast, four of 13 skeletally mature patients had a recurrence and required further surgery. This suggests that eosinophilic granuloma has a low rate of recurrence in skeletally immature patients.

Drug resistance mutations in HIV-1-infected subjects during protease inhibitor-containing highly active antiretroviral therapy with nelfinavir or indinavir

OBJECTIVES

The aim of this retrospective study was to evaluate treatment outcome and characterize the pattern of genotype mutations in subjects with treatment failure on highly active antiretroviral therapy (HAART) containing nelfinavir or indinavir.

STUDY DESIGN AND METHODS

The database of the Swiss HIV Cohort Study was screened for all subjects naive to protease inhibitor (PI) treatment who started HAART with nelfinavir or indinavir, responded initially (HIV-RNA <400 copies/ml) and received >24 weeks of treatment. Responders with subsequent treatment failure (HIV-RNA >1000 copies/ml, bordered by HIV-RNA >400 copies/ml) were selected for genotypic analysis.

RESULTS

Initial treatment response, maintenance of response and subsequent virological failure were observed at a comparable frequency in 1143 nelfinavir and 1555 indinavir subjects. Of the treatment-naive patients, 13% who took nelfinavir and 16% who took indinavir had HIV-RNA >1000 copies/ml at least once. These values increased to 24 and 27%, respectively, for reverse transcriptase inhibitor-experienced subjects. Genotypic analysis in a subset of subjects with virological failure identified 30N as the only primary mutation in the nelfinavir subjects (8 out of 21, 38%) whereas isolated or combined 82A/T and 461/L mutations were detected in the indinavir subjects (9 out of 20, 45%).

CONCLUSIONS

In this population of previously PI-naive subjects, the rate of virological failure and the frequency of resistance mutations at the time of virological failure were comparable in subjects receiving nelfinavir- or indinavir-containing HAART. In nelfinavir subjects, 30N was the only primary mutation whereas isolated or combined 82A/T and 461/L mutations were detected in indinavir subjects.

Combination therapy with saquinavir soft gelatin capsules in children with human immunodeficiency virus infection

OBJECTIVES

To evaluate the pharmacokinetics, tolerance, safety and antiviral activity of the HIV protease inhibitor, saquinavir, formulated as soft gelatin capsules (SQV-SGC), given in combination with nucleoside antiretroviral agents (NRTIs) with or without nelfinavir in HIV-infected children.

METHODS

This was an open label study of HIV-infected children ages 3 to 16 years, conducted in two parts. In Part 1 of the study 14 children were treated orally with SQV-SGC (initially given in three 33-mg/kg doses daily; dosage adjusted to 50 mg/kg three times daily based on initial pharmacokinetics) and two NRTIs. Addition of nelfinavir was permitted for children who did not achieve a predetermined steady state target plasma saquinavir exposure. In Part 2 a new group of 13 children received SQV-SGC (33 mg/kg three times daily) in combination with nelfinavir and one or two NRTIs. Pharmacokinetics were assessed after the first dose and 4 weeks into treatment (steady state). Patients were treated for 72 and 48 weeks in Parts 1 and 2, respectively.

RESULTS

Most adverse events were mild; the most commonly reported were diarrhea, abdominal discomfort and headache. Two children were withdrawn from the study because of adverse events (one each of nausea and dysphagia) related to the study treatment. There were no deaths or serious adverse events attributed to the study medication. Steady state saquinavir area under the plasma concentration vs. time curves (AUC24) were 6,210 and 11,010 ng/h/ml for Parts 1 and 2, respectively. Compared with baseline measurements median changes in plasma HIV RNA concentrations were -2.12 log10 copies/ml [5 of 14 (36%) with HIV RNA <50 copies/ml) (Week 72)] and -2.58 log10 copies/ml [8 of 13 (62%) <50 copies/ml) (Week 48)] in Parts 1 and 2, respectively. The median changes in CD4+ lymphocyte count were +292 and +154 cells/microl for Parts 1 and 2, respectively. Genotypic resistance assays revealed a low frequency of saquinavir-associated resistance mutations after 48 weeks of therapy, with only 2 of 27 children having substitutions at positions 48V and/or 90M.

CONCLUSIONS

Combination therapy with SQV-SGC was well-tolerated and safe in HIV-infected children, and antiviral activity was observed. Saquinavir plasma concentrations were lower than expected, particularly for Part 1 (SQV-SGC plus NRTIs), but addition of nelfinavir increased saquinavir exposures.

Expression and genetic analysis of XIAP-associated factor 1 (XAF1) in cancer cell lines

X-linked inhibitor of apoptosis protein (XIAP) is a potent modulator of programmed cell death. XIAP specifically binds and inhibits the function of caspase-3, -7, and -9, key effector proteases of apoptosis. We recently isolated, by yeast two-hybrid screening, a novel 34-kDa zinc finger protein, XIAP-associated factor 1 (XAF1). Both the caspase inhibiting and the anti-apoptotic abilities of XIAP were found to be blocked by overexpressed XAF1. Here, we report the isolation and characterization of the human XAF1 gene. The xaf1 gene consists of seven exons spanning 18 kb. Fluorescence in situ hybridization analysis localized the xaf1 locus at 17p13.2, telomeric to the p53 gene. The xaf1 locus was further refined to YAC 746C10, approximately 3 cM distal to TP53. Microsatellite analysis of the xaf1 locus using the NCI 60 cell line panel revealed significantly decreased heterozygosity at all three polymorphic markers tested, suggesting that allelic loss of the xaf1 gene is prevalent in cancer cell lines. Examination of the same NCI cell line panel for xaf1 RNA expression demonstrated that cancer cell lines exhibited very low levels of mRNA relative to normal human liver. In contrast, XIAP mRNA levels were relatively high in the majority of cancer cell lines tested. We propose that a high level of XIAP to XAF1 expression in cancer cells may provide a survival advantage through the relative increase of XIAP anti-apoptotic function.

Baseline human immunodeficiency virus type 1 phenotype, genotype, and RNA response after switching from long-term hard-capsule saquinavir to indinavir or soft-gel-capsule saquinavir in AIDS clinical trials group protocol 333

AIDS Clinical Trials Group protocol 333 was an open-label trial of a switch from saquinavir (SQV) hard capsules (SQVhc) to indinavir (IDV) or saquinavir soft-gel capsules (SQVsgc) after >48 weeks of prior treatment with SQVhc. Eighty-nine subjects received IDV or SQVsgc or continued to receive SQVhc and continued unchanged treatment with non-protease-inhibitor antivirals for 8 weeks. Subjects receiving SQVhc then switched treatment to IDV. Baseline drug susceptibility and protease gene sequencing were done; 12 codons related to IDV and SQV resistance were analyzed. After 112 weeks (median) of SQVhc, the fall in human immunodeficiency virus (HIV) type 1 RNA level from baseline was significantly greater with IDV and was inversely correlated with the number of protease substitutions. The number of substitutions also correlated with baseline CD4 cell count, HIV-1 RNA level, SQV experience, and drug susceptibility. Substitution at codon 10, which occurred only in isolates with >/=2 substitutions, was associated with blunted RNA response. IDV IC(50) correlated with HIV-1 RNA response after the switch to IDV but added little predictive power once the genotype was considered.

Current treatment approaches for neoplastic meningitis: nursing management of patients receiving intrathecal DepoCyt

PURPOSE/OBJECTIVES

To review neoplastic meningitis and the nursing implications for the intrathecal administration of chemotherapy.

DATA SOURCES

Published research and educational manuscripts, books, conference proceedings, and personal experience.

DATA SYNTHESIS

Standard treatment for neoplastic meningitis includes radiotherapy to the neuraxis to palliate symptomatic disease, intrathecal chemotherapy to eradicate cancer cells in the cerebrospinal axis, and systemic chemotherapy. Intrathecal liposomal cytarabine (DepoCyt), a novel lipid-encapsulated chemotherapeutic agent, prolongs tumor exposure to cytotoxic levels of cytarabine, improves patient response rates, and prolongs time to clinical progression.

CONCLUSIONS

DepoCyt prolongs the half-life of cytarabine in the central nervous system, resulting in improved patient response to therapy and delayed disease progression.

IMPLICATIONS FOR NURSING PRACTICE

The clinical success of DepoCyt treatment depends on effective implementation of the treatment regimen, attentiveness to patient and family education, and adverse-event management.

Implementation of COMPUTER-ASSISTED Treatment Planning in a Prison Psychiatric Facility

1. An effective treatment plan must be behaviorally based and descriptive, yet concise, with clear, measurable outcomes. It should be the synergistic product of the interdisciplinary team process. 2. The use of a computer program and a firm commitment to making the team process work can generate a superior, clinically sound, practical, legible product, while liberating professionals for more clinical time. 3. One does not need to be a computer expert to use software to generate treatment plans. The program you choose must be capable of being modified by the user to respond to changing needs of patients and capabilities of staff.

An outbreak of mumps among young adults in Vancouver, British Columbia, associated with 'rave' parties

In early 1997 an unexpectedly high number of cases of mumps was reported in Vancouver, British Columbia.

METHODS

A case control study was conducted to address four objectives: 1) Describe the outbreak and the population at risk, 2) examine the impact of mumps on this population, 3) identify personal risk factors for infection, and 4) test the hypothesis that social gatherings, 'rave' parties in particular, were a risk factor in this outbreak.

RESULTS

Mumps infection was associated with: attending a rave party [OR = 17; 95% CI: 2.7-710], residing in Vancouver [OR = 3.7; 95% CI: 1.4-10], and contact with a person with mumps [OR = 13; 95% CI: 2-552], during the 'exposure' period. Vaccine effectiveness, ascertained by self-reported immunization status, was 80% [95% CI: 29%-96%].

CONCLUSIONS

Attendance at rave parties was associated with mumps infection during this outbreak. Many persons aged 17-40 may remain susceptible to mumps; in BC these persons are eligible for one dose of MMR and should be encouraged to be vaccinated.

Identification of biased amino acid substitution patterns in human immunodeficiency virus type 1 isolates from patients treated with protease inhibitors

Human immunodeficiency virus type 1 (HIV-1) amino acid substitutions observed during antiretroviral drug therapy may be caused by drug selection, non-drug-related evolution, or sampling error introduced by the sequencing process. We analyzed HIV-1 sequences from 371 untreated patients and from 178 patients receiving a single protease inhibitor. Amino acid substitution patterns during treatment were compared with inferred substitution patterns arising evolutionarily without treatment. Our results suggest that most treatment-associated amino acid substitutions are caused by selective drug pressure, including substitutions not previously associated with drug resistance.

A novel adenoviral vector expressing human Fas/CD95/APO-1 enhances p53-mediated apoptosis

Recent evidence suggests an intriguing link between p53 and the Fas pathway. To evaluate this association further, we utilized a recombinant adenoviral vector (AdWTp53) to overexpress wild-type p53 in lung cancer (A549, H23, EKVX and HOP92) and breast cancer (MDA-MB-231 and MCF-7) cell lines and observed an increase in the Fas/CD95/APO-1 protein levels. Furthermore, this increase correlated with the sensitivity of the cell lines to p53-mediated cytotoxicity. To examine the effects of Fas over-expression in cells resistant to p53 over-expression, we constructed AdFas, an adenoviral vector capable of transferring functional human Fas to cancer cells. Interestingly, infection of p53-resistant MCF-7 cells with AdFas sensitized them to p53-mediated apoptosis. These studies indicate that combined over-expression of Fas and wild-type p53 may be an effective cancer gene therapy approach, especially in cells relatively resistant to p53 over-expression.

Aspects of X-ray diffraction on single spider fibers

Diffraction patterns of silk from several spider species have been obtained by synchrotron radiation using a beam size > or = 10 microm. Single fiber diffraction patterns were obtained for fiber diameters down to a few microns. Diffraction patterns recorded with a 10 microm wide X-ray beam displayed fiber texture. The presence of two fractions of different crystallinity was confirmed for a single Nephila clavipes fiber. The orientation distribution of the polymer chains of the crystalline fraction along the fiber axis was found to be about 23 degrees full-width at half maximum (fwhm). The azimuthal spread of the short-range order fraction was about 86 degrees fwhm.