Thermoregulation in periparturient rabbit does and their neonatal kits with different litter sizes during West African winter

The study evaluated the changes in body temperatures and hematological parameters in periparturient rabbit does and the dynamics of body surface temperature in neonatal rabbit kits during West African winter. The variables were measured in 21 rabbits, comprising periparturient (n = 12) and dry (n = 9) does, and after kindling, the kits were grouped based on litter size, into small (4 kits per litter; n = 24) and large (5-7 kits per litter; n = 34) litter. Results revealed that all body temperatures of the does were lower (p < 0.05) during gestation compared with lactation period or dry does in all hours of the day, and the PCV was significantly higher in lactating than dry does. At birth, small litter kits had higher (p < 0.05) body weight and morning body surface temperature than the large litter kits. The large litter kits showed distinct (p < 0.05) diurnal variation in body surface temperature from birth, while diurnal variation in the small litter kits was absent (P > 0.05) in the first three days after birth. It was concluded that pregnant rabbits and large litter kits may have poor thermoregulation during West African winter, and thus, the need for special protective housing to improve productivity.

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.

Effect of interventional edge-to-edge repair in tricuspid regurgitation on dimensions of the annulus

Funding Acknowledgements

Type of funding sources: None.

Background

The technique of percutaneous tricuspid valve edge-to-edge repair (pTVR) depends upon the connection of leaflets in the area of regurgitation using a coaptation device. By closing the coaptation device a considerable tractive force is applied on the leaflets, which might have an effect on the valve annulus. The aim of this study was to examine the impact of device implantation on tricuspid annular dimensions.

Methods

During pTVR, 3D zoom loops of the tricuspid valve (TV) were acquired before and after clip placement using transesophageal echocardiography. Measurements of TV annular dimensions included the following parameters: annulus area (TV area), maximal diameter, minimal diameter, and eccentricity index (Figure 1). Tenting area was derived from a four-chamber view of the valve. Tricuspid regurgitation (TR) severity was graded from 1+ to 5+ by measuring vena contracta area (VCA3D) in 3D full volume color Doppler loop using multiplanar reconstruction.  Right atrial (RA) and ventricular volumes (RVVd3D, RVVs3D) and function (RVEF3D) were assessed in a 3D full volume loop.

Results

The study population consisted of 97 patients (age 78 ± 6 years, 47 male), undergoing pTVR at our hospital. As expected, cavity dimension correlated with TV area size (for RVVd3D r = 0.51, p &lt; 0.001 and for RA volume r = 0.71, p &lt; 0.001). The mean TV annular area was significantly reduced (Annular area 8.53 ± 2.23 cm²/m²BSA vs. 7.55 ± 2.18 cm²/m²BSA, p &lt; 0.001) and the shape of the annulus became more oval (Eccentricity index 1.2 ± 0.15 vs. 1.29 ± 0.17, p &lt; 0.001) after pTVR. The reduction in annular area (12 ± 7%, range 0.7-28%) was only modestly correlated with the number of implanted coaptation devices (r = 0.30, p &lt; 0.001) and the percentage reduction of VCA3D (r =0.36, p &lt; 0.001). In the patient group with an annular area change ≥12%, a decrease in TR grade to ≤2+ by pTVR was achieved in 83% of cases, whereas only 62% of patients achieved moderate TR when the change in area was below 12%.

Conclusion

  pTVR using coaptation devices reduces the area of the TV annulus. This effect may be modestly correlated to the number of devices implanted. Abstract Figure.

Impact of endocardial leads on the effectiveness of interventional edge-to-edge repair of tricuspid regurgitation

Funding Acknowledgements

Type of funding sources: None.

Background

A considerable proportion of patients who are considered for percutaneous tricuspid valve edge-to-edge repair (pTVR) interventions have endocardial lead induced tricuspid regurgitation (TR). The aim of this study was to examine the impact of lead-leaflet interaction on the effectiveness of pTVR.

Methods

For each patient, the lead position within the tricuspid valve (central, commissural, or towards one of the three leaflets) and the type of lead-leaflet interaction (leaflet impingement or adhesion) were identified during thorough 2D/3D transthoracic and transesophageal echocardiography examinations. Before and after pTVR, echocardiographic data, including 3D full-volume datasets, were obtained and quantified. TR severity was graded from 1+ to 5+, based upon the effective regurgitant orifice area by the PISA method (EROAPISA) and the vena contracta area (VCA3D) as measured by multiplanar reconstruction from a 3D color Doppler loop. Maximal diastolic tricuspid annulus area from a 3D zoom image, tricuspid tenting area, and right atrial volume were quantified. Right ventricular assessments included ejection fraction (RVEF3D) and diastolic (RVVd3D) and systolic (RVVs3D) volumes. 

Results

Out of 99 patients who underwent pTVR at our hospital, 38 patients had implanted cardiac devices of the following types: pacemakers (n = 25, 66%), cardiac defibrillators (n = 7, 18%), and biventricular pacemakers (n = 6, 16%). In 24 (63%) of these device patients, TR grade was ≤2+ after pTVR. In 14 of the device patients, TR grade remained severe after intervention (Grade 3+ in 15%, grade 4+ in 11%, and Grade 5+ in 11% of the device group). In comparison, in 78% of patients without endocardial leads, moderate TR was achieved after pTVR. Figure 1 shows the distribution of lead positions within the tricuspid valve. A relevant lead-leaflet interference (rLLI) for pTVR interventions was defined as impingement or adhesion in the target area of the coaptation device (anteroseptal or posteroseptal). Binary logistic regression analysis showed an increase risk (Odds ratio 11, R2 0.34, 95% CI 0.019-0.44, p = 0.003) for a suboptimal pTVR result (TR grade &gt; 2+ after intervention) in patients with rLLI. Although patients with rLLI (n = 17) had significantly higher VCA3D values as compared to patients without rLLI (n = 21), it was not predictive for pTVR results. Echocardiographic parameters of right ventricular and tricuspid valve dimensions showed only a trend to higher values in the group with rLLI (Table 1).

Conclusion

  Endocardial lead induced TR negatively impacts the effectiveness of pTVR irrespective of the initial degree of TR. Abstract Figure.  Abstract Table 1 Echocardiographic parameters

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.

Effect of interventional edge-to-edge repair in tricuspid regurgitation on ring dimensions

Background

The concept of percutaneous tricuspid valve edge-to-edge repair (pTVR) is based on the connection of leaflets in the area of insufficiency using a coaptation device. By closing the coaptation device a considerable tractive force is applied on the leaflets, which might have an effect on the valve ring. Aim of the study was to examine the impact of device implantation on tricuspid ring dimensions.

Methods

During pTVR 3D zoom loops of tricuspid valve were acquired before and after clip placement using transoesophageal echocardiography. Measurements of TV ring dimensions included the following parameters: ring area (TV area), maximal diameter, minimal diameter, eccentricity index (Figure 1). Tenting area was derived from a four-chamber view of the valve. In addition, regurgitation severity was graded from 1+ to 5+ by measuring vena contracta area (VCA3D) in 3D full volume colour Doppler loop using multiplanar reconstruction. Right atrial (RA) and ventricular volumes (RVVd3D, RVVs3D) and function (RVEF3D) were assessed in a 3D full volume loop.

Results

The study population comprised 97 patients (age 78±6 years, 47 male), who underwent pTVR at our hospital. As expected cavity dimension correlated with TV area size (for RVVd3D r=0.51, p&lt;0.001 and for RA volume r=0.71, p&lt;0.001). The mean TV ring area was significantly reduced (ring area 8.53±2.23 cm2/m2BSA vs. 7.55±2.18 cm2/m2BSA, p&lt;0.001) and the ring shape became more oval (Eccentricity index 1.2±0.15 vs. 1.29±0.17, p&lt;0.001) after pTVR. The reduction of ring area (12±7%, range 0.7–28%) showed an only modest correlation to the number of implanted coaptation devices (r=0.30, p&lt;0.001) and percentage reduction of VCA3D (r=0.36, p&lt;0.001). In the patient group with a ring area change ≥12% a reduction to TR grade ≤2+ by pTVR was achieved in 83% of cases, whereas only 62% of patients reached moderate TR when area change was below 12%.

Conclusion

pTVR using coaptation devices reduces the ring area. This effect is related to the number of devices implanted.

Funding Acknowledgement

Type of funding sources: None.

Echocardiographic predictors of the effectiveness of interventional edge-to-edge repair in tricuspid valve regurgitation

Background

Percutaneous tricuspid valve edge-to-edge repair (pTVR) is a promising interventional technique for patients with tricuspid regurgitation (TR), but guidance regarding patient selection and echocardiographic screening is lacking. The aim of this study was to identify echocardiographic parameters which may predict pTVR success.

Methods

Before and after pTVR, echocardiographic data, including 3D full-volume datasets, were obtained and quantified. Right ventricular assessments included ejection fraction (RVEF3D) and diastolic (RVVd3D) and systolic (RVVs3D) volumes. Also evaluated were: right atrial (RA) volume, effective regurgitant orifice area by PISA method (EROAPISA), vena contracta area (VCA3D) by multiplanar reconstruction from a 3D colour Doppler loop (Figure 1a), maximal diastolic tricuspid annulus area from a 3D zoom image (Figure 1b), and tricuspid tenting area. TR severity was graded according to EROAPISA and VCA3D as grade 1+ to 5+.

Results

Patients (n=99, age 79±6 years, 48 male) with at least moderate to severe TR undergoing pTVR were consecutively included. The patients were divided into groups according to their post-pTVR TR grade. Group 1 had TR grade ≤2+, and group 2 had TR grade ≥3+.Echocardiographic parameters before pTVR for both groups are presented in Table 1. As expected, patients with TVR ≥3+ after pTVR had significantly worse pre-intervention echocardiographic measurements of TR severity, valve dimensions, and chamber volumes. ROC curves for the prediction of TR ≤2+ (mild to moderate) after pTVR (defined as VCA3D &lt;0.75 cm2 and EROAPISA &lt;0.4 cm2) were drawn for different echocardiographic features (Figure 2). VCA3D by 3D colour Doppler yielded the highest area under the ROC curve followed by TV anatomy measurements (Annulus area3D, Tenting area) and right atrial volume.

Conclusion

A thorough evaluation of TR and valve dimensions by 3D echocardiography, particularly the evaluation of VCA3D by 3D colour Doppler, aids in the prediction of the probability of pTVR success.

Funding Acknowledgement

Type of funding sources: None.

Impact of endocardial leads on the effectiveness of interventional edge-to-edge repair of tricuspid regurgitation

Background

A considerable proportion of patients who are considered for percutaneous tricuspid valve edge-to-edge repair (pTVR) interventions have endocardial lead induced tricuspid regurgitation (TR). The aim of this study was to examine the impact of lead-leaflet interaction on the effectiveness of pTVR.

Methods

For each patient, the lead position within the tricuspid valve (central, commissural, or towards one of the three leaflets) and the type of lead-leaflet interaction (leaflet impingement or adhesion) were identified during thorough 2D/3D transthoracic and transesophageal echocardiography examinations. Before and after pTVR, echocardiographic data, including 3D full-volume datasets, were obtained and quantified. TR severity was graded from 1+ to 5+, based upon the effective regurgitant orifice area by the PISA method (EROAPISA) and the vena contracta area (VCA3D) as measured by multiplanar reconstruction from a 3D color Doppler loop. Maximal diastolic tricuspid annulus area from a 3D zoom image, tricuspid tenting area, and right atrial volume were quantified. Right ventricular assessments included ejection fraction (RVEF3D) and diastolic (RVVd3D) and systolic (RVVs3D) volumes.

Results

Out of 99 patients who underwent pTVR at our hospital, 38 patients had implanted cardiac devices of the following types: pacemakers (n=25, 66%), cardiac defibrillators (n=7, 18%), and biventricular pacemakers (n=6, 16%). In 24 (63%) of these device patients, TR grade was ≤2+ after pTVR. In 14 of the device patients, TR grade remained severe after intervention (Grade 3+ in 15%, grade 4+ in 11%, and Grade 5+ in 11% of the device group). In comparison, in 78% of patients without endocardial leads, only moderate TR was achieved after pTVR. Figure 1 shows the distribution of lead positions within the tricuspid valve. A relevant lead-leaflet interference (rLLI) for pTVR interventions was defined as impingement or adhesion in the target area of the coaptation device (anteroseptal or posteroseptal). Binary logistic regression analysis showed an increase risk (Odds ratio 11, R2 0.34, 95% CI 0.019–0.44, p=0.003) for a suboptimal pTVR result (TR grade &gt;2+ after intervention) in patients with rLLI. Although patients with rLLI (n=17) had significantly higher VCA3D values as compared to patients without rLLI (n=21), it was not predictive for pTVR results. Echocardiographic parameters of right ventricular and tricuspid valve dimensions showed only a trend to higher values in the group with rLLI (Table 1).

Conclusion

Endocardial lead induced TR negatively impacts the effectiveness of pTVR irrespective of the initial degree of TR.

Funding Acknowledgement

Type of funding sources: None.

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.

Identification of novel VHL targets that are associated with the development of renal cell carcinoma

von Hippel-Lindau (VHL) disease is a dominantly inherited family cancer syndrome characterized by the development of retinal and central nervous system haemangioblastomas, renal cell carcinoma (RCC) and phaeochromocytoma. Specific germline VHL mutations may predispose to haemangioblastomas, RCC and phaeochromocytoma to a varying extent. Although dysregulation of the hypoxia-inducible transcription factor-2 and JunB have been linked to the development of RCC and phaeochromocytoma, respectively, the precise basis for genotype-phenotype correlations in VHL disease have not been defined. To gain insights into the pathogenesis of RCC in VHL disease we compared gene expression microarray profiles in a RCC cell line expressing a Type 1 or Type 2B mutant pVHL (RCC-associated) to those of a Type 2A or 2C mutant (not associated with RCC). We identified 19 differentially expressed novel VHL target genes linked to RCC development. Eight targets were studied in detail by quantitative real-time polymerase chain reaction (three downregulated and five upregulated by wild-type VHL) and for six genes the effect of VHL inactivation was mimicked by hypoxia (but hypoxic-induction of smooth muscle alpha-actin 2 was specific for a RCC cell line). The potential role of four RCC-associated VHL target genes was assessed in vitro. NB thymosin beta (TMSNB) and proteinase-activated receptor 2 (PAR2) (both downregulated by wt pVHL) increased cell growth and motility in a RCC cell line, but aldehyde dehydrogenase (ALDH)1 and ALDH7 had no effect. These findings implicate TMSNB and PAR2 candidate oncogenes in the pathogenesis of VHL-associated RCC.

Self-reported weight and height: implications for obesity research

BACKGROUND

Self-reported weight and height are under- and over-reported, respectively, in epidemiologic studies. This tendency, which may adversely affect study operations, has not been evaluated among subjects being enrolled into a weight-loss program.

METHODS

Self-reported weight, height, and body mass index (BMI) were compared to measured values in 97 overweight or obese (BMI>27.3) women being enrolled into a randomized, controlled trial of two behavioral interventions for weight loss. The effects of demographic factors, baseline weight, baseline height, and baseline BMI on weight and height reporting were assessed.

RESULTS

There was a significant difference between measured and reported weight (mean difference=-3.75 lb, p=0.0001) and height (mean difference=+0.35 in., p=0.0007). The mean difference between measured and reported BMI was -1.14 kg/m(2) (p=0.0001). Unemployed, retired, or disabled women were more likely to under-report their BMI than employed women (p=0.001). Six percent of subjects who were initially considered eligible for the study on the basis of the self-report were eventually excluded from the study because they did not meet the inclusion criterion for BMI.

CONCLUSIONS

Obese women who seek weight-loss assistance tend to under-report their weight and over-report their height, suggesting that self-reported data are likely to be inaccurate. Misreporting is apparently influenced by employment and disability and has the potential to complicate recruitment of subjects for research studies.

[Chiari I malformation with syringomyelia treated by decompression of the cranio-spinal junction and tonsillectomy. Apropos of 8 cases]

We report a series of 8 patients with syringomyelia and associated Chiari I malformation treated between 1992 and 1996 using a cranio-vertebral decompression with tonsil resection. The follow up period ranged from 6 months through 4 years (mean: 28 months). Neurological symptoms and signs improved in 7 patients (87%), and were stabilized in 1 (13%). At 6 months, postoperative MRI showed that the syringe has decreased in all patients. We emphasize the respect of the different stages of surgical procedure (limited foramen magnum opening, arachnoid preservation, tonsillar subpial aspiration, arachnoid suture and dural closure). Other of treatment and their results are reviewed.

Sex-specific aging in the nematode Panagrellus redivivus

Females of the free-living nematode Panagrellus redivivus have a greater mean life span than do males. Unmated animals live longer than mated individuals. Decreased nutritional levels or increased temperature decrease life span. The sex differences in life expectancy are also shown by behavioral activity and osmotic fragility. Behavioral activity decreases in older animals.