Winds at the Mars 2020 Landing Site. 2. Wind Variability and Turbulence

Wind speeds measured by the Mars 2020 Perseverance rover in Jezero crater were fitted as a Weibull distribution. InSight wind data acquired in Elysium Planitia were also used to contextualize observations. Jezero winds were found to be much calmer on average than in previous landing sites, despite the intense aeolian activity observed. However, a great influence of turbulence and wave activity was observed in the wind speed variations, thus driving the probability of reaching the highest wind speeds at Jezero, instead of sustained winds driven by local, regional, or large-scale circulation. The power spectral density of wind speed fluctuations follows a power-law, whose slope deviates depending on the time of day from that predicted considering homogeneous and isotropic turbulence. Daytime wave activity is related to convection cells and smaller eddies in the boundary layer, advected over the crater. The signature of convection cells was also found during dust storm conditions, when prevailing winds were consistent with a tidal drive. Nighttime fluctuations were also intense, suggesting strong mechanical turbulence. Convective vortices were usually involved in rapid wind fluctuations and extreme winds, with variations peaking at 9.2 times the background winds. Transient high wind events by vortex-passages, turbulence, and wave activity could be driving aeolian activity at Jezero. We report the detection of a strong dust cloud of 0.75-1.5 km in length passing over the rover. The observed aeolian activity had major implications for instrumentation, with the wind sensor suffering damage throughout the mission, probably due to flying debris advected by winds.

Laparoscopic surgery of congenital paraesophageal hernia in newborns and infants

INTRODUCTION

Congenital paraesophageal hernia (CPH) is a rare pathology in pediatric patients. Clinical signs may occur as early as in newborns, which means it requires early surgical repair.

CLINICAL CASES

This is a series of three patients under 1 year of age diagnosed with type IV CPH - with symptoms occurring since they were newborns - who underwent laparoscopic surgical repair. One patient had been diagnosed prenatally. Age at surgery was 6 days, 36 days, and 9 months, respectively. Weight at surgery was 3.60 kg, 3.79 kg, and 8.20 kg, respectively. The patients underwent laparoscopy, with removal of the hernia sac, closure of the diaphragmatic pillars, placement of a reinforcement absorbable mesh, and Nissen fundoplication. Mean operating time was 130 minutes. No intraoperative complications were recorded. One patient developed a sliding hernia, which was subsequently repaired without complications. Mean follow-up time was 24 months.

Pediatric surgical activity during the SARS-CoV-2 pandemic: experience at a tertiary hospital

OBJECTIVES

The primary objective was to describe the characteristics and demographics of the surgical procedures carried out at a tertiary hospital during the SARS-CoV-2 pandemic. The secondary objective was to study the impact of the pandemic on the acute appendicitis cases treated at our healthcare facility and to compare them with a pre- SARS-CoV-2 period.

MATERIAL AND METHODS

A retrospective study of all patients undergoing surgery at the pediatric surgery department in the pandemic period, from the beginning of the state of emergency in Spain until the first restrictions were removed, was conducted.

RESULTS

A total of 61 patients underwent surgery in 58 days vs. 406 patients in the same 2019 period (p < 0.00001). 59.01% of surgeries were urgent. 5.1% of patients had a positive SARS-CoV-2 diagnostic test. 30 different procedures were carried out, with appendectomy being the most frequent one (n = 13, 19.6% of patients). 61.5% of appendicitis cases were complicated vs. 42.4% in the non-COVID period (p = 0.17). Surgical approach was open in 46.1% of patients vs. 6.1% in the non-COVID period (p = 0.004). No statistically significant differences were found in terms of complication rate or hospital stay.

CONCLUSIONS

During the SARS-CoV-2 pandemic, a significant decrease in the number of daily procedures was noted, with more than half being urgent. Appendicular pathologies were in a more advanced stage than usual, with a clear trend towards open surgery vs. laparoscopy.

Thyroid surgery in pediatric patients: causes and results

OBJECTIVE

Even though thyroid surgery is rare in pediatric patients, frequency has increased in the last years. The objective of this study was to analyze the causes and results of these procedures in a pediatric surgical facility.

PATIENTS AND METHODS

Retrospective study including all patients requiring thyroid surgery in our department from 2000 to 2019. Demographic data, diagnostic data, associated pathology, type of surgical procedure, pathological results, and intraoperative and postoperative complications were recorded.

RESULTS

47 patients with a mean age of 8.9 ± 3.9 years at surgery were included. The most frequent diagnosis was MEN syndrome (n = 30, 29 MEN 2A and 1 MEN 2B), followed by thyroid papillary carcinoma (n = 5), follicular adenoma (n = 5), multinodular goiter (n = 4), follicular carcinoma (n = 1), thyroglossal duct papillary carcinoma (n = 1), and Graves-Basedow syndrome (n = 1). 38 total thyroidectomies (73.7% of which were prophylactic), 3 double hemithyroidectomies, 5 hemithyroidectomies, and 5 lymphadenectomies were performed. No intraoperative complications or recurrent laryngeal nerve lesions were noted. Mean postoperative hospital stay was 1.3 ± 0.6 days. 7 patients had transitory asymptomatic hypoparathyroidism, and 1 patient had persistent symptomatic hypoparathyroidism. Pathological results of prophylactic thyroidectomies were: 18 C cell hyperplasias, 7 microcarcinomas, and 3 cases without histopathological disorders.

CONCLUSIONS

Thyroid surgery in pediatric patients is safe if performed by specialized personnel. Even though it remains rare, frequency has increased in the last years.

Meteorological Predictions for Mars 2020 Perseverance Rover Landing Site at Jezero Crater

The Mars Regional Atmospheric Modeling System (MRAMS) and a nested simulation of the Mars Weather Research and Forecasting model (MarsWRF) are used to predict the local meteorological conditions at the Mars 2020 Perseverance rover landing site inside Jezero crater (Mars). These predictions are complemented with the COmplutense and MIchigan MArs Radiative Transfer model (COMIMART) and with the local Single Column Model (SCM) to further refine predictions of radiative forcing and the water cycle respectively. The primary objective is to facilitate interpretation of the meteorological measurements to be obtained by the Mars Environmental Dynamics Analyzer (MEDA) aboard the rover, but also to provide predictions of the meteorological phenomena and seasonal changes that might impact operations, from both a risk perspective and from the perspective of being better prepared to make certain measurements. A full diurnal cycle at four different seasons (L_s 0°, 90°, 180°, and 270°) is investigated. Air and ground temperatures, pressure, wind speed and direction, surface radiative fluxes and moisture data are modeled. The good agreement between observations and modeling in prior works [Pla-Garcia et al. in Icarus 280:103-113, 2016; Newman et al. in Icarus 291:203-231, 2017; Vicente-Retortillo et al. in Sci. Rep. 8(1):1-8, 2018; Savijarvi et al. in Icarus, 2020] provides confidence in utilizing these models results to predict the meteorological environment at Mars 2020 Perseverance rover landing site inside Jezero crater. The data returned by MEDA will determine the extent to which this confidence was justified.

Bronchoalveolar lavage usefulness in the pediatric population

OBJECTIVE

To analyze bronchoalveolar lavage diagnostic effectiveness and impact on therapeutic management in pediatric patients.

MATERIAL AND METHODS

Retrospective study of patients undergoing bronchoalveolar lavage at the pediatric surgery department from 2009 to 2019. The sample was divided into two groups: hemato-oncological patients and non-hemato-oncological patients. Demographic variables, bronchoalveolar lavage result, and subsequent therapeutic attitude were collected.

RESULTS

45 bronchoalveolar lavages were carried out in 38 patients. The hemato-oncological group consisted of 25 bronchoalveolar lavages. Patient mean age was 9.99 ± 2.34 years. 80% of patients had received anti-infective treatment prior to bronchoalveolar lavage. Bronchoalveolar lavage culture was positive in 52% of cases. Bronchoalveolar lavage results translated into therapeutic management change in 24% of cases (6/25). 3 postoperative complications were recorded, all mild. In the non-hemato-oncological group (n = 20), mean age was 6.70 ± 5.17 years. Bronchoalveolar lavage was positive in 25% of cases, and translated into management change in 5% of patients. Complication rate in this group was 30%. 2 patients required mechanical ventilation.

CONCLUSIONS

According to our results, bronchoalveolar lavage in hemato-oncological patients helps achieve microbiological diagnosis in infectious respiratory conditions and is relatively well-tolerated. In non-hemato-oncological patients, diagnostic and therapeutic usefulness is low, and complication rate is not negligible. The risk-benefit balance should be individually considered in each patient.

Measuring esophageal anastomotic stricture index as a predictor of dilatation following esophageal atresia surgical repair

INTRODUCTION

Anastomotic stricture is the most common complication following esophageal atresia (EA) surgical repair. The objective of this study was to evaluate Anastomotic Stricture Index (ASI: relationship between pouch and stricture diameters in the postoperative esophagram) as a predictor of the need for esophageal dilatation.

METHODS

A retrospective review of all patients undergoing EA repair in our healthcare facility from 2009 to 2017 was designed. Proximal pouch ASI (proximal ASI) and distal pouch ASI (distal ASI) in the first and second postoperative esophagram were calculated, and correlation with the number of esophageal dilatations required was studied. For statistical analysis purposes, Spearman's correlation test and ROC curves were used.

RESULTS

Of the 31 patients included, 21 (67.7%) required esophageal dilatation, and 11 (35.5%) required 3 or more dilatations. The relationship between ASIs in the first esophagram and the need for esophageal dilatation was not statistically significant (p >0.05). The relationship between proximal ASI (RHO = 0.84, p <0.05) and the number of dilatations in the second esophagram was statistically significant. None of the patients with <0.55 proximal ASI required dilatation; patients with 0.55-0.79 proximal ASI required less than 3 dilatations; and patients with >0.79 proximal ASI had a high risk of requiring 3 or more dilatations.

CONCLUSION

According to our study, measuring ASI in the second esophagram proves useful in predicting EA patients' postoperative management, especially when it comes to identifying patients with lower risk of undergoing multiple dilatations.

Effects of the MY34/2018 Global Dust Storm as Measured by MSL REMS in Gale Crater

The Rover Environmental Monitoring Station (REMS) instrument that is onboard NASA's Mars Science Laboratory (MSL) Curiosity rover. REMS has been measuring surface pressure, air and ground brightness temperature, relative humidity, and UV irradiance since MSL's landing in 2012. In Mars Year (MY) 34 (2018) a global dust storm reached Gale Crater at L_s ~190°. REMS offers a unique opportunity to better understand the impact of a global dust storm on local environmental conditions, which complements previous observations by the Viking landers and Mars Exploration Rovers. All atmospheric variables measured by REMS are strongly affected albeit at different times. During the onset phase, the daily maximum UV radiation decreased by 90% between sols 2075 (opacity ~1) and 2085 (opacity ~8.5). The diurnal range in ground and air temperatures decreased by 35K and 56K, respectively, with also a diurnal-average decrease of ~2K and 4K respectively. The maximum relative humidity, which occurs right before sunrise, decreased to below 5%, compared with pre-storm values of up to 29%, due to the warmer air temperatures at night while the inferred water vapor abundance suggests an increase during the storm. Between sols 2085 and 2130, the typical nighttime stable inversion layer was absent near the surface as ground temperatures remained warmer than near-surface air temperatures. Finally, the frequency-domain behavior of the diurnal pressure cycle shows a strong increase in the strength of the semidiurnal and terdiurnal modes peaking after the local opacity maximum, also suggesting differences in the dust abundance inside and outside Gale.

Postoperative surgical complications after lung transplantation

This is a review article on the main postoperative complications after lung transplantation: airways complications, vascular complications, pleural complications, surgical wound complications, and abdominal complications. Incidence data, severity, and major management regimens are reported. Postoperative complications after lung transplantation result in a significantly increased morbidity and mortality, with early diagnosis and therapy being extremely important.

WITHDRAWN:Postoperative surgical complications after lung transplantation

This article has been withdrawn for editorial reasons because the journal will be published only in English. In order to avoid duplicated records, this article can be found at http://dx.doi.org/10.1016/j.rppnen.2014.09.007. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Soil diversity and hydration as observed by ChemCam at Gale crater, Mars

The ChemCam instrument, which provides insight into martian soil chemistry at the submillimeter scale, identified two principal soil types along the Curiosity rover traverse: a fine-grained mafic type and a locally derived, coarse-grained felsic type. The mafic soil component is representative of widespread martian soils and is similar in composition to the martian dust. It possesses a ubiquitous hydrogen signature in ChemCam spectra, corresponding to the hydration of the amorphous phases found in the soil by the CheMin instrument. This hydration likely accounts for an important fraction of the global hydration of the surface seen by previous orbital measurements. ChemCam analyses did not reveal any significant exchange of water vapor between the regolith and the atmosphere. These observations provide constraints on the nature of the amorphous phases and their hydration.

Recommendations on the use of everolimus in lung transplantation

The antiproliferative effect of everolimus provides a therapeutic option in the immunosuppression therapy of lung transplantation, by reducing both the risk of acute rejection and the process of progressive fibrosis that determines chronic graft rejection. However, few data on the use of everolimus in lung transplantation have been published to date, and the specific indications of the drug, along with the most adequate time for its introduction or dosing, have not been defined yet. The aim of this article is to propose recommendations for the use of everolimus in lung transplant recipients, including indications, dosing schedules and the use of concomitant immunosuppression. This consensus document has been developed by experts of all the Spanish lung transplant groups from the review of the existing literature and the clinical experience.

A multicenter study of valganciclovir prophylaxis up to day 120 in CMV-seropositive lung transplant recipients

Seventy-six cytomegalovirus (CMV)-seropositive lung transplant recipients receiving valganciclovir (900 mg/day) for CMV prophylaxis were compared with a group of 87 patients receiving oral ganciclovir (3000 mg/day). Prophylaxis was administered to day 120 post-transplantation and follow-up was 1 year. In addition, a study was conducted on risk factors for CMV infection/disease. CMV disease incidence was 7.9% and 16.1% for valganciclovir and oral ganciclovir, respectively (p = 0.11). Patients receiving valganciclovir had fewer viral syndromes (2.6% vs. 11.5%, p < 0.05), a similar rate of tissue-invasive disease (5.2% vs. 4.6%, p = ns), longer time-to-onset of CMV infection/disease (197.5 vs. 155.2 days, p < 0.05), and a lower probability of infection/disease while on prophylaxis (1.3% vs. 12.6%, p < 0.01). Nonetheless, leukopenia incidence was higher with valganciclovir (15.8% vs. 2.3%, p < 0.01), as was the need for treatment withdrawal due to adverse effects (11.8% vs. 1.1%, p < 0.01). CMV infection was similar in both groups (32.9% vs. 34.5%). Induction therapy with basiliximab and glucocorticosteroid treatment were independent risk factors for developing CMV infection/disease. In conclusion, valganciclovir prophylaxis results in a low incidence of CMV disease in lung transplant recipients and appears more effective than oral ganciclovir. Despite the comparatively higher incidence of adverse events with valganciclovir, the drug can be considered safe for prophylaxis.

Prevalence and management of gastrointestinal complications in lung transplant patients: MITOS study group

INTRODUCTION

No studies have yet been performed to evaluate the prevalence of gastrointestinal (GI) complications in solid organ transplant recipients in Spain.

MATERIALS AND METHODS

An observational, cross-sectional study to evaluate the prevalence and management of GI complications in transplanted patients was conducted via a written questionnaire given to doctors at their practice.

RESULTS

A total of 58 lung transplant recipients were included. Their mean age was 52.6 +/- 10.8 years; 65% of the patients were men; and the mean time since the transplant was 2.1 +/- 2.3 years. GI complications were seen in 48.6% of the lung transplant patients. Regarding the management, the most frequently used measure was the prescription of gastric protectors (70.5%). In seven patients, the immunosuppressive treatment was also modified (reduced, discontinued temporarily, or discontinued permanently); however, the figure is so low that no conclusions can be drawn from this result.

CONCLUSIONS

The prevalence of GI complications in lung transplant was over 50%, and these complications affected patients' daily activities in most cases. In lung transplant recipients, there was a higher prevalence of nausea and abdominal pain and a lower of diarrhea and dyspepsia than what was observed in other type of transplant recipients.

Basiliximab in lung transplantation: preliminary experience

BACKGROUND

Basiliximab is a chimeric anti-interleukin-2 monoclonal antibody that has shown safety and efficacy in the prophylaxis of acute organ rejection in renal, liver, heart, and kidney-pancreas transplantation (Tx). The aim of this study was to present our initial experience with the use of Basiliximab in lung Tx.

METHODS

Basiliximab (2 doses of 20 mg on day 0 and day 4) was administered to 16 patients treated with cyclosporine, azathioprine, and steroids between September 13, 2001 and August 26, 2003, including 12 men and 4 women patients with a mean age of 56.5 years (range, 19-69). The indication for use in transplantations were: reduced renal function (n = 14), post-Tx acute renal failure (n = 1) and steroid-resistant acute rejection (n = 1). Eight double-lung and eight single-lung Tx were performed for emphysema (n = 6), idiopathic pulmonary fibrosis (n = 7), silicosis (n = 2), and cystic fibrosis retransplantation (n = 1).

RESULTS

The incidence of acute rejection was 16.6% (2 patients). Infections included cytomegalovirus (CMV) 33.3% (n = 4), bacterial 16.6% (n = 2), and fungal 8.3% (n = 1). Two patients died in the postoperative period and another at 3 months. There was no reaction to the medicine, and no malignancies or Bronchiolitis Obliterans Syndrome (BOS) during a follow-up period of more than 1 year in 10 patients.

CONCLUSION

Basiliximab appeared to reduce the incidence of acute organ rejection and showed a good safety profile in terms of infections and adverse events.

[Membranous nephropathy and crescentic glomerulonephritis]

The most frequent causes of glomerular diseases whose main clinical syndrome are nephrotic syndrome and acute renal failure may have several causes: acute tubular necrosis, thrombosis of renal veins, acute tubulointerstitial nephritis. Infrequently, the association between primary glomerular disease (membranous nephropathy and others) and crescentic glomerulonephritis can cause this clinical picture. We describe a young woman without systemic disease with nephrotic syndrome and acute renal failure secondary to membranous nephropathy and superimposed crescentic glomerulonephritis. She received steroids and cyclophosphamide with stabilization of renal function after two months of follow-up.

[Diagnosis of the infectious complications of continuous ambulatory peritoneal dialysis by 99mTc-HMPAO labelled leukocytes]

OBJECTIVE

To assess the utility of abdominal scintigraphy with 99mTc-HMPAO labelled leukocytes in the diagnosis of infectious complications of continuous ambulatory peritoneal dialysis (CAPD).

MATERIAL AND METHODS

17 patients in CAPD were evaluated (35 studies). They were divided into three groups: group control in asymptomathic patients (5), group of studies in patients with suspicion of exit site infection/catheter tunnel (18) and group of studies in patients with clinical suspicion of peritonitis (12). All patients underwent abdominal scintigraphy with 99mTc-HMPAO labelled leukocytes. The results were compared to final clinical diagnosis, assessing the exit site or dialysis liquid external aspect, material or exit site secretion culture and clinical follow up.

RESULTS

In the case studied, we obtained high sensitivity and specificity values for the exit site infection diagnosis (83 % and 75 % respectively), and a sensitivity of 100 % in the diagnosis of peritonitis as well. We detected a case of catheter tunnel infection confirmed by culture. No pathological uptake was observed in any control case.

CONCLUSIONS

Abdominal scintigraphy with 99mTc-HMPAO labelled leukocytes allows the early diagnosis of infectious complications of CAPD, and the control of treatment response, avoiding its unnecessary prolongation.

[Pancoast syndrome and endobronchial tumor infiltration as the first manifestation of Hodgkin lymphoma]

The most common cause of Pancoast syndrome is bronchogenic carcinoma. Other less common causes are solid tumor metastases, other chest tumors, infections, and hematologic neoplasms. Pancoast syndrome due to lymphoma is very rare, and cases described in the literature are essentially associated with non-Hodgkin lymphomas. In a review of the literature we found a single case of Pancoast syndrome secondary to a Hodgkin lymphoma; however, the syndrome manifested during recurrence of disease in that patient. We report a case of nodular sclerosis Hodgkin lymphoma which first manifested clinically as Pancoast syndrome and which was initially diagnosed by bronchial biopsy.

[Non-Hodgkin lymphoma, IgA nephropathy and renal cell carcinoma]

Glomerular diseases could complicate lymphoid malignancies. We identified a patient with non-Hodgkin's lymphoma showing elevated levels of serum IgA1 paraprotein, renal infiltration by B cells, IgA nephropathy and renal cell carcinoma. It seems that there is a possible pathogenic relationship between these entities.

[Familial focal and segmentary hyalinosis]

Focal segmental glomerulosclerosis represents a finding in several renal disorders, characterized by proteinuria and sometimes by arterial hypertension and progressive decline in renal function. There are primary (idiopathic and familial) and secundary forms. In the last 20 years several familial cases has been reported, with a great genetic heterogeneity (dominant and recessive forms) and with multiple associations with particular MHC class-I and class-II gene loci, being Al, DR3 o DR7 the most frequently reported. We described three members of same family with focal segmental hyalinosis that shared the HLA haplotype A31 B61 DR13. This association has not been described previously. We highlight that genetic and acquired factors (obesity, hypertension...) could have importance in the development of progressive renal failure in these patients.

[Prognostic significance of programmed dialysis in patients who initiate renal substitutive treatment. Multicenter study in Spain]

BACKGROUND

The aim of our study was to analyse patient characteristics, mortality and costs, all of them in relation to whether starting dialysis was planned or unplanned.

METHODS

A total of 362 patients (227 male and 135 female) from five hospitals of the National Health System, who were started on chronic renal replacement therapy (RRT) during 1996 and 1997 were included. Patients who were started on RRT after acute renal failure were excluded. We carried out a retrospective analysis of the demographic characteristics, patients' conditions at the time of initiating dialysis and outcome and costs at six and thirty-six months of treatment. Patients were classified as planned (PL-D) or unplanned dialysis (UNPL-D), depending on whether or not the patient had a vascular or peritoneal access ready to use for initiating RRT.

RESULTS

One hundred and eighty-six patients (51.4%) started on dialysis in the PL-D group whereas 176 (48.6%) did it as UNPL-D. In this latter group, 135 (37.3% of the total) had previously been monitored by a nephrologist, and 41 (11.3%) initiated dialysis without previous nephrological follow-up. UNPL-D was associated with older age (p < 0.001), non-nephrological follow-up (p < 0.001), diabetes (34.7% vs 22.6%) (p = 0.011), haemodialysis as a first mode of RRT (94.9 vs 81.7%) (p < 0.001), higher comorbidity risk (p < 0.001), dialysis initiation with uraemic symptoms or fluid overload (p < 0.001), increased blood transfusion requirement (p < 0.001) and lower serum albumin (p < 0.001), creatinine clearance (p < 0.001), haemoglobin concentration (p < 0.001), and weight (p = 0.002). In the PL-D group the main primary renal diseases were glomerular and polycystic disease, whereas interstitial and diabetic nephropathy were higher in UNPL-D group (p = 0.005). Multivariate analysis showed that previous non nephrological follow-up, uraemic symptoms, interstitial nephritis as primary renal disease correlated with UNPL-D initiation, and it was followed by choosing haemodialysis as first RRT. UNPL-D was also associated with increased number of days of hospitalization at the initiation of dialysis, and during the first 6 months (p < 0.001), increase of hospitalization days (p = 0.009), and increased 6-month-mortality (10.2% vs 3.2%) (p = 0.015, log rank test), and three-year mortality (24.2 vs 36.9%) (p = 0.006, log rank test). The costs of UNPL-D were fivefold that of the PL-D group.

CONCLUSION

UNPL-D has been associated with worse overall clinical conditions at the initiation of chronic replacement therapy, choosing haemodialysis as first RRT, increased morbi-mortality and subsequent increase of costs.

Human urinary bladder carcinomas express adenovirus attachment and internalization receptors

The use of adenoviral vectors as potent gene delivery systems requires expression of the Coxsackievirus/adenovirus receptor (CVADR) on the target cell surface. This receptor is important for virus attachment to the cell surface. For effective internalization of the vector into the target cell the integrins alpha(v)beta(3) and/or alpha(v)beta(5) are needed. Since there have been reports of loss of CVADR in bladder cancer cell lines, we wanted to investigate the expression of this receptor in bladder carcinoma biopsies. Surgical biopsies, as well as five human bladder cancer cell lines, were analyzed for expression of CVADR, the integrins alpha(v)beta(3) and alpha(v)beta(5) and MHC class I. Further, we studied the ability to transduce these cell lines using adenoviral vectors. Immunohistochemistry revealed that all biopsies (27/27) were positive for CVADR. Some variation in expression was evident, and superficially growing tumors stained more strongly than invasive ones. Most human tumors expressed the integrin alpha(v)beta(5) (14/24), whereas integrin alpha(v)beta(3) was less frequently seen (3/20). The established cell lines were efficiently transduced with adenoviral vectors, and transduction could be reduced with anti-CVADR antibodies. The abundance of appropriate viral receptors on tumor biopsy cells is a further argument for using adenoviral vectors in gene therapy of bladder cancer.

Effect of high-cell-density fermentation of Candida utilis on kinetic parameters and the shift to respiro-fermentative metabolism

Candida utilis NRRLY-900 was grown in a high-cell-density continuous culture without oxygen limitation. Glucose or molasses was used as carbon source at 30 g l(-1) or 100 g (reducing sugars) l(-1). At 30 g glucose l(-1), the dilution rate (D) immediately before the change in respiratory metabolism (Dr) was approximately 0.40 h(-1). At this value of D, the corresponding culture in molasses did not reach the Dr value. When the reducing sugar concentration in the feed was 100 g l(-1), the Dr was 0.15 h(-1) for glucose and 0.3 h(-1) for molasses. When D>Dr, accumulation of ethanol and organic acids occurred, due to physiological changes in C. utilis. The changes observed were a decrease in the biomass yield coefficient per gram of oxygen consumed (YO2) and a sudden increase in the specific oxygen consumption rate (qO2) for each substrate. Therefore, at growth rates above Dr in a high-cell-density culture, C. utilis acquired a flexible catabolism directed towards alternative fermentation routes. The D at which metabolic changes took place seemed to depend on the nature and concentration of the carbon source. Biomass productivity was higher with molasses than with glucose when the fermenter was operated at high D values.

Regulation of cellulases and xylanases from a derepressed mutant of Cellulomonas flavigena growing on sugar-cane bagasse in continuous culture

When the wild type Cellulomonas flavigena was grown on glycerol, xylose or cellobiose, it produced basal levels of carboxymethyl-cellulase (CMCase), filter-paperase (FPase) and xylanase activities. By comparison, a catabolic derepressed mutant strain of the same organism produced markedly higher levels of these enzymes when grown on the same carbon sources. Sugar-cane bagasse induced both the wild type and the mutant strain to produce three- to eight-time higher levels of FPase and xylanase than was observed with xylose or cellobiose. Continuous culture was used to determine the minimal cellobiose or glucose concentrations that repress the enzyme synthesis in both strains. 2.5 g l(-1) glucose repressed FPase and xylanases from wild type, while 1.6 times more glucose was needed to repress the same activities in the PN-120 strain. In the same way, twofold more cellobiose was needed to reduce by 75% the CMCase and xylanase activities in the mutant compared to the wild type. The FPase in the presence of 4 g l(-1) cellobiose did not change in the same strain. Therefore, its derepressed and feedback resistant characters of PN-120 mutant are evident. On the other hand, isoelectrofocused crude extracts of mutant and wild strains induced by sugar-cane bagasse, did not show differences in protein patterns, however, the Schiffs staining was more intense in the PN-120 than in the wild strain. These results point out that the mutational treatment did not apparently change the extracellular proteins from mutant PN-120 and this could affect their regulation sites, since derepressed and feed-back resistant enzymes may be produced.

Cell death with atypical features induced by the novel antitumoral drug CHS 828, in human U-937 GTB cells

N-(6-(4-chlorophenoxy)hexyl)-N'-cyano-N"-4-pyridylguanidine (CHS 828), with promising antitumoral effects in vitro and in vivo, is currently in clinical Phase I and II studies. Its exact mechanism of action is unclear, but previous studies indicate that CHS 828 induces a controlled, delayed mode of cell death. The characteristics of the cell death process were investigated in vitro in the apoptosis-prone cell line U-937 GTB. Mitochondria showed hyperpolarization at 24 to 32 h and a subsequent late disruption of mitochondria membrane potential (Deltapsi(m)). Between 44 and 72 h of CHS 828 exposure, there was an increasing frequency of terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) positive cells indicative of apoptosis, but caspase-3 was only modestly increased and caspases-8 and -9 showed no activation upon CHS 828 exposure. Furthermore, the morphology of exposed cells did not conform to classical apoptosis, and viability and morphology were unaffected by inhibition of caspases. Thus, CHS 828 induces several unexpected features in this system, suggesting a potentially novel mechanism of action.

Temporal effects of the novel antitumour pyridyl cyanoguanidine (CHS 828) on human lymphoma cells

CHS 828, a novel pyridyl cyanoguanidine, has shown potent antitumour activity both in vitro and in vivo and is currently undergoing phase I evaluation in humans in collaboration with the European Organization for Research and Treatment of Cancer (EORTC). Here we study the temporal effects of CHS 828 on cytotoxicity, protein and DNA synthesis, cellular morphology and ultra structure using the lymphoma cell line U-937 GTB as the primary tumour model. In vitro analysis of tumour cell survival in response to CHS 828 revealed a cytotoxic effect progressively increased as a function of exposure time with maximum efficacy observed after 72 h. Activity of CHS 828 on U-937 GTB cells grown in vivo was also found. CHS 828 induced-cell death was dependent on intact protein synthesis and most cells appeared to lose their membrane integrity in the presence of a relatively well preserved nuclear structure. The results indicate that CHS 828 induced active and delayed cell death with a non-apoptotic morphology.

A hollow fiber model for in vitro studies of cytotoxic compounds: activity of the cyanoguanidine CHS 828

The hollow fiber assay is currently used as an in vivo model for anticancer drug screening in nude mice, but it can also be used as an in vitro model. In the current study, an in vitro hollow fiber model was used to study the effect and mode of induced cell death of a new cyanoguanidine, CHS 828. Human leukemia, adenocarcinoma and lymphoma cell lines as well as primary cultures of human tumor cells from patients with chronic lymphocytic leukemia (CLL) and ovarian cancer (OC) and normal human lymphocytes were cultured in semipermeable hollow fibers. The fibers were incubated for 3 or 14 days prior to CHS 828 exposure for 72 h, followed by determination of living cell density by MTT staining. For cell morphology, using harvested cultures on cytospin slides had technical advantages compared to using paraffin sections of the formalin-fixed fibers. CHS 828 showed higher antitumor activity on CLL and normal human lymphocyte cultures compared to OC cultures, and cell lines cultured 3 days were more sensitive than those cultured 14 days. Morphological examination of CHS 828-treated cultures revealed a mixture of apoptosis and necrosis.

[Complications of transesophageal echocardiography with dobutamine]

The transesophageal echocardiographic approach improves the diagnostic power of transthoracic stress echocardiography. However, it is a seminvasive test and its safety is not well established. Our objective was to compare the incidence of complications of transesophageal and transthoracic dobutamine echocardiography. We collected data from 63 patients with inadequate transthoracic window, who underwent transesophageal dobutamine echocardiography and were compared with 100 patients in whom the transthoracic approach was diagnostic. Baseline blood pressure and heart rate were higher in the first group. There were no differences in those parameters at the end of the test. Neither were atropine administration and side effects more frequent in any of the groups. There were no cases of ventricular fibrillation, ventricular tachycardia, acute myocardial infarction, intractable angina or intolerance to the probe. Side effects were equally present in both groups. Transesophageal dobutamine stress echocardiography is a safe test that can be used in patients with coronary artery disease and poor transthoracic window.

Postsurgical pleurodesis with autologous blood in patients with persistent air leak

BACKGROUND

Persistent air leak after operation on the lung is one of the most common problems encountered by thoracic surgeons. We present 6 patients who underwent pleurodesis with autologous blood for persistent air leak after operation.

METHODS

Between June 1993 and January 1998, pleurodesis with autologous blood was performed in 6 patients who had air leak of more than 10 days' duration after operation for non-small cell lung cancer. A sample of peripheral blood was taken from the patient's arm and immediately introduced into the chest tube with no additives. The chest tube was left unclamped and off suction, connected to the waterseal drainage, and kept 60 cm above the patient's chest. The next day, the waterseal and chest roentgenogram were reviewed before the chest tube was removed.

RESULTS

A persistent air leak with a mean duration of 16.7 days was observed after the initial operation. Fifty to 250 mL of blood was introduced one time into the chest tube. No patient experienced pain, respiratory difficulty, fever, or episodes of coughing during the procedure. After 24 hours, no air leak was detected in the waterseal drainage in any patient.

CONCLUSIONS

On the basis of these preliminary findings, we believe pleurodesis with autologous blood is a safe and effective method for treating persistent air leak after a thoracic surgical procedure.