Oral squamous cell carcinomas and oral potentially malignant disorders: A Latin American study

OBJECTIVE

To determine the frequency of oral squamous cell carcinoma (OSCC) associated or not with oral potentially malignant disorders (OPMD), and the epidemiological profile and traditional risk factors in Latin America.

METHODS

A retrospective observational study was conducted in 17 Latin American centres. There were included cases of OSCC, analysing age, gender, OSCC and their association with previous OPMD. Clinicopathological variables were retrieved. The condition of sequential-OSCC versus OSCC-de novo (OSCC-dn) was analysed concerning the aforementioned variables. Quantitative variables were analysed using Student's t-test, and qualitative variables with chi-square.

RESULTS

In total, 2705 OSCC were included with a mean age of 62.8 years old. 55.8% were men. 53.75% of the patients were smokers and 38% were common drinkers. The lateral tongue border was the most affected site (24.65%). There were regional variations in OPMD, being leukoplakia the most frequent. Of the overall 2705 OSCC cases, 81.4% corresponded to OSCC-dn, while s-OSCC were 18.6%. Regarding lip vermillion SCC, 35.7% corresponded to de novo lip SCC and 64.3% were associated with previous OPMD.

CONCLUSIONS

In Latin America, OSCC-dn seems to be more frequent with regional variations of some clinical and histopathological features. Further prospective studies are needed to analyse this phenomenon.

Cognitive social zones for improving the pedestrian collision avoidance with mobile robots

Social behaviors are crucial to improve the acceptance of a robot in human-shared environments. One of themost important social cues is undoubtedly the social space. This human mechanism acts like a repulsive field to guaranteecomfortable interactions. Its modeling has been widely studied in social robotics, but its experimental inference has beenweakly mentioned. Thereby, this paper proposes a novel algorithm to infer the dimensions of an elliptical social zone froma points-cloud around the robot. The approach consists of identifying how the humans avoid a robot during navigationin shared scenarios, and later use this experience to represent humans obstacles like elliptical potential fields with thepreviously identified dimensions. Thus, the algorithm starts with a first-learning stage where the robot navigates withoutavoiding humans, i.e. the humans are in charge of avoiding the robots while developing their tasks. During this period,the robot generates a points-cloud with 2D laser measures from its own framework to define the human-presence zonesaround itself but prioritizing its closest surroundings. Later, the inferred social zone is incorporated to a null-space-based(NSB) control for a non-holonomic mobile robot, which consists of both trajectory tracking and pedestrian collisionavoidance. Finally, the performance of the learning algorithm and the motion control is verified through experimentation.

Multi-objective control for cooperative payload transport with rotorcraft UAVs

A novel kinematic formation controller based on null-space theory is proposed to transport a cable-suspended payload with two rotorcraft UAVs considering collision avoidance, wind perturbations, and properly distribution of the load weight. An accurate 6-DoF nonlinear dynamic model of a helicopter and models for flexible cables and payload are included to test the proposal in a realistic scenario. System stability is demonstrated using Lyapunov theory and several simulation results show the good performance of the approach.

Abstract P4-04-05: Primary endocrine therapy (PETx) induces PAM50 intrinsic subtype migration with prognostic implications

Backgorund: ER activation is a major ruler of cell biology in ER+ve breast cancer. Hence, ER dependent gene expression at diagnosis, may unveil most of the oncogenic mechanisms responsible of potential tumour relapse and metastasis. Thus, we hypothesized that oestrogen deprivation through PETx may unveil underlying tumour biology with deeper prognostic implications. To explore this, we studied changes in PAM50 intrinsic subtyping and Risk of Recurrence score throughout PETx and their correlation with known prognostic factors.

Methods: Clinical-pathological data were evaluated in a series of patients with stage I-III ER-positive/HER2-negative breast cancer treated in 6 centers in Spain with PETx during more than two months with available baseline and surgical samples. The expressions of 50 genes were measured in baseline samples and surgical specimens using the nCounter platform. Intrinsic subtypes and Risk of Recurrence score (ROR) were determined by the research-based PAM50 predictor. Response by ultrasonography (US) and magnetic resonance (RMI) between diagnosis and before surgery and PEPI score in surgical samples were used as the endpoints. Association between two variables was evaluated using χ2 test or Pearson correlation. All statistical tests were two-sided and considered significant when P≤0.05.

Results: Gene expression profile was feasible in 58 pre/post sample pairs with a median of 7.8 months (range 2.5-40.6) of PETx with AIs (98.3%) or tamoxifen (1.7%). At baseline, 68.9%(n=40) were classified as Luminal A, followed by Luminal B (24.1%; n=14), HER2 enriched (HER2-E) (5.2%; n=3) and Normal-like (1.8%; n=1). Radiologic response did not change significantly according to intrinsic subtype either by MRI or US (P>0.05). Instead, PEPI score varied according to intrinsic subtype (P=0.024).Thirteen (32%) of LumA, while neither of LumB or HER2-E tumours showed a PEPI score Group 1. PETx resulted in changes in the intrinsic subtype in 29 (50%) of tumours

Table 1 Her2-E postLumA postLumB postNormal postHer2 pre2 (66.7%)1 (33.33%)00LumA pre1 (2.5%)21 (52.5%)3 (7.5%)15 (37.5%)LumB pre06 (42.86%)5 (35.71%)3 (21.43%)Normal pre0001 (100%)

. Of note, 2 of 3 (66.7%) HER2 tumors, and 5 of 14 (35.7%) LumB tumors did not change their profile. Forty-eight (83%) tumours showed a decrease in ROR score after PETx (P<0.001). ROR was over 30 in 29 tumours (49.1%) at baseline and 16 (27%) at surgery. Change in ROR was moderately correlated with percentage of change in Ki-67 [correlation: 0.417 (P<0.01)]. Correlation of surgical tumour subtype with IHC markers of cell-viability/apoptosis will be presented.

Conclusion: Oestrogen deprivation of luminal tumours through PETx results in profound changes in tumour biology including a migration in intrinsic subtype in 50% of tumours.

Correlation of the largely decreased ROR with changes in Ki67 reveals the potential prognostic additional information generated by profiling tumours after PETx. ER-blockade may unveil underlying tumour oncogenic capabilities for relapse, survival and metastasis.

Hence, the post-PETx gene expression profile, molecular subtype and ROR may bear incremental prognostic and predictive information generating a novel scenario for optimal clinical decision making.

Citation Format: Larburu L, Paré L, Rezola R, Carrera M, Buch E, Gimenez J, Quiroga V, Fernandez M, Aragón S, Pascual T, Prat A, Urruticoechea A. Primary endocrine therapy (PETx) induces PAM50 intrinsic subtype migration with prognostic implications [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-04-05.

Pheochromocytoma of the Organ Zuckerkandl

INTRODUCTION

Pheochromocytomas (PCCs);, or intra-adrenal paragangliomas (PGLs);, are neuroendocrine tumors arising within the adrenal medulla. Extra-adrenal paragangliomas may arise in the sympathetic or parasympathetic paraganglia and more rarely in other organs. One of the most common extra-adrenal sites is in the organ of Zuckerkandl, a collection of chromaffin cells near the origin of the inferior mesenteric artery or near the aortic bifurcation. The following is a case of a patient with resistant hypertension secondary to an extra-adrenal paraganglioma in the organ of Zuckerkandl.

CASE

The patient is a 43 year old man with a history of depression, type 2 diabetes mellitus, and hypertension who was sent to the emergency department by his primary care physician for severely elevated blood pressures. Patient also had diaphoresis, tachycardia, and a new, fine tremor of his left hand. Upon presentation, the patient's blood pressure was 260/120 mmHg with a heart rate of 140 beats per minute. Plasma fractionated metanephrines sent on admission revealed significantly elevated levels of total plasma metanephrines (2558 pg/mL);, free metanephrine (74 pg/ml); and free normetanephrine (2484pg/mL);. An I-123 metaiodobenzylguanidine (MIBG); scan showed abnormal uptake in the lower abdomen at the level of the aortic bifurcation. Patient was started on alpha-blockade, with subsequent addition of a beta-blocker prior to surgery. Patient underwent surgical removal of the tumor with pathology consistent with a paraganglioma.

DISCUSSION

Pheochromocytomas and paragangliomas are responsible for approximately 0.5 percent of cases of secondary hypertension. Many different biochemical markers have been used to aid in the diagnosis of PCC/PGL including plasma catecholamines, plasma metanephrines, urine fractionated metanephrines, urine catecholamines, total metanephrines and vanillymandellic acid. Definitive management of a PCC and PGL involves surgical removal of the tumor. Finally, there should be a discussion with each patient to determine if he or she should undergo genetic testing, as studies show that approximately 25 percent of catecholamine producing PCCs and PGLs are due to heritable genetic mutations.

Estimating influenza vaccine effectiveness in Spain using sentinel surveillance data

We aimed to estimate influenza vaccine effectiveness (VE) against laboratory-confirmed influenza during three influenza seasons (2010/11 to 2012/2013) in Spain using surveillance data and to compare the results with data obtained by the cycEVA study, the Spanish component of the Influenza Monitoring Vaccine Effectiveness (I-MOVE) network. We used the test-negative case–control design, with data from the Spanish Influenza Sentinel Surveillance System (SISS) or from the cycEVA study. Cases were laboratory-confirmed influenza patients with the predominant influenza virus of each season, and controls were those testing negative for any influenza virus. We calculated the overall and age-specific adjusted VE. Although the number of patients recorded in the SISS was three times higher than that in the cycEVA study, the quality of information for important variables, i.e. vaccination status and laboratory results, was high in both studies. Overall, the SISS and cycEVA influenza VE estimates were largely similar during the study period. For elderly patients (> 59 years), the SISS estimates were slightly lower than those of cycEVA, and estimates for children (0–14 years) were higher using SISS in two of the three seasons studied. Enhancing the SISS by collecting the date of influenza vaccination and reducing the percentage of patients with incomplete information would optimise the system to provide reliable annual influenza VE estimates to guide influenza vaccination policies.

Influenza vaccine effectiveness in Spain 2013/14: subtype-specific early estimates using the cycEVA study

Adjusted early estimates of the 2013/14 influenza vaccine effectiveness (VE) in Spain for all age groups was 35% (95% CI: -9 to 62), 33% (95% CI: -33 to 67) and 28% (95% CI: -33 to 61) against any influenza virus type, A(H1N1)pdm09 and A(H3N2) viruses, respectively. For the population targeted for vaccination, the adjusted VE was 44% (95% CI: -11 to 72), 36% (95% CI: -64 to 75) and 42% (95% CI: -29 to 74), respectively. These preliminary results in Spain suggest a suboptimal protective effect of the vaccine against circulating influenza viruses.

Polymerization of ∊-Caprolactone in a Twin Screw Extruder

The purpose of this work is to model the bulk polymerization of ∊-caprolactone in a corotating twin screw extruder. Starting from kinetic data and rheological laws previously defined, we use a twin screw flow modelling software to calculate the progress of the polymerization along the extruder. Experiments are performed to assess the influence of processing conditions (feed rate, screw speed, barrel temperature, initiator concentration) and to validate the model. They put in evidence the control of the polymerization process by the temperature and the residence time in the extruder. It is shown that a good correlation between theoretical and experimental results can only be obtained if accurate kinetic and rheological data are used in the model.

Bulk Polymerization of ∊-Caprolactone in Twin Screw Extruder

The ∊-caprolactone bulk polymerisation, initiated by tetra-propoxy titanium, was investigated in a co-rotating twin screw extruder. On the basis of pressure measurements, the process dynamic modelling was achieved. The pressure drop at the exit die of the extruder was correlated to the rheological behaviour of the melt polycaprolactone owing to equations which characterise the flow inside the die. The residence time distribution modelling was determined with an in-line Ultra-Violet fluorescence method. Thus, the combination of both modellings leads to the process dynamic modelling. This work constitutes the basis for an approach of the process regulation by the way of an internal model control. Simulation has given good results. However, the large response time to the control, relative to the process dynamic, constitutes effectiveness limiting factor for experimental control of the process.

Early estimates of the effectiveness of the 2011/12 influenza vaccine in the population targeted for vaccination in Spain, 25 December 2011 to 19 February 2012

We present early estimates of influenza vaccine effectiveness (VE) in the population targeted for vaccination, during 25 December 2011 to 19 February 2012. The adjusted VE was 55% (95% CI: 3 to 79) against any type of influenza virus and 54% (95% CI: 1 to 79) against influenza A(H3N2) virus. This suggests a moderate protective effect of the vaccine in the targeted population in a late influenza epidemic with limited match between vaccine and circulating strains.

The Solubility of Unirradiated UO2 In Both Perchlorate And Chloride Test Solutions. Influence of the Ionic Medium

The solubility of a crystalline unirradiated UO2 (s) has been studied under reducing conditions at 25°C in three different ionic media: 0.008 mol dm–3 NaCIO4, 1 and 5 mol dm-3 NaCl+. The species responsible for the solubility in perchlorate medium are U(OH)3 and U(OH)4, with the stability constants log β13 = -0.4(±0.2) and log β14 = -5.7(±0.1), respectively. The solubility in both1! and 5 M chloride media is explained at pH values higher than 6 by the species U(OH)4 with log β14 = -5.5(±0.2) while at lower pH values an abnormal behaviour is observed, with higher uranium concentrations in solution and a proton independent solubility for pH values lower than 4. The XPS observations of the reacted solids do not show the presence of solid surface phases other than uranium dioxide, with an upper oxidation state of UO2.1.

Mineralization enhancement of a recalcitrant pharmaceutical pollutant in water by advanced oxidation hybrid processes

Degradation of the biorecalcitrant pharmaceutical micropollutant ibuprofen (IBP) was carried out by means of several advanced oxidation hybrid configurations. TiO(2) photocatalysis, photo-Fenton and sonolysis - all of them under solar simulated illumination - were tested in the hybrid systems: sonophoto-Fenton (FS), sonophotocatalysis (TS) and TiO(2)/Fe(2+)/sonolysis (TFS). In the case of the sonophoto-Fenton process, the IBP degradation (95%) and mineralization (60%) were attained with photo-Fenton (FH). The presence of ultrasonic irradiation slightly improves the iron catalytic activity. On the other hand, total removal of IBP and elimination of more than 50% of dissolved organic carbon (DOC) were observed by photocatalysis with TiO(2) in the presence of ultrasound irradiation (TS). In contrast only 26% of mineralization was observed by photocatalysis with H(2)O(2) (TH) in the absence of ultrasound irradiation. Additional results showed that, in the TFS system, 92% of DOC removal and complete degradation of IBP were obtained within 240 min of treatment. The advanced oxidation hybrid systems seems to be a promising alternative for full elimination/mineralization for the recalcitrant micro-contaminant IBP.

Ultrasonic treatment of water contaminated with ibuprofen

The application of ultrasound (US) waves for remediation of wastewater is an area of increasing interest and promising results. The aim of this paper is to evaluate the influence of several parameters of the US process on the degradation of ibuprofen (IBP), a widely used non-steroidal anti-inflammatory recalcitrant drug found in water. Applied US power, dissolved gas, pH and initial concentration of IBP were the parameters investigated under sonication (300 kHz). Ultrasound increased the degradation of IBP from 30 to 98% in 30 min. Initial rate of IBP degradation was evaluated in the range of 1.35 and 6.1 micromolL(-1)min(-1) for initial concentrations of 2 to 21 mgL(-1) or 9.7 micromolL(-1) to 101 micromolL(-1), respectively. Under air and oxygen the degradation rate of IBP was 4 micromolL(-1)min(-1) being higher than that when argon was used. The most favorable degradation pH was acidic media. Complete removal of IBP was achieved but some dissolved organic carbon (DOC) remained in solution showing that long-lived intermediates were recalcitrant to the US irradiation. However, chemical and biological oxygen demands (COD and BOD(5)) indicated that the process oxidize the ibuprofen compound to biodegradable substances removable in a subsequent biological step.

Intestinal stenting in preterm, very-low-birth-weight infants with necrotizing enterocolitis and multiple perforations

We present 2 cases of necrotizing enterocolitis with multiple intestinal perforations or areas of segmental bowel necrosis in preterm, very-low-birth-weight infants. We reviewed their charts and researched the related literature. We used SILASTIC (Silmag, Argentina) intestinal stents to avoid multiple formal bowel anastomosis or stomas and longer resections, and to reduce operative time. In the first case, we externalized the stent through the first and last perforation; and in the second, through a proximal jejunostomy and the orifice left after an appendectomy. This method was useful in avoiding short bowel syndrome in both infants, and they were discharged successfully. They are currently 31/2 and 2 years old, respectively, eating without any restriction and with mild developmental delays. Treatment of preterm infants with multiple bowel perforations or areas of bowel necrosis requires a maximal effort to preserve as much intestinal length as possible. Use of the SILASTIC stent technique provides a good treatment variant in selected cases to preserve bowel length, reduce operative time, and avoid short bowel syndrome.

Cystic fibrosis in a southern Brazilian population: characteristics of 90% of the alleles

Cystic fibrosis (CF) is a genetic disease that frequently leads to death in infancy among Europeans and their descendants. The goals of the present study were to analyze the molecular aspects of CFTR gene characterizing mutations, their frequencies, and the haplotypes formed by four CFTR gene intragenic markers, IVS8-6(T)n, IVS8CA, IVS17bTA and IVS17bCA, in a southern Brazilian population of Caucasian origin. DNA samples from 56 non-related CF patients were analyzed using scanning techniques (single strand conformation polymorphism and denaturing gradient gel electrophoresis), restriction fragment length polymorphism and direct DNA sequencing to identify the mutations. Our results revealed a total of 25 different CF mutations representing nearly 90% of CF alleles, two being novel mutations. Microsatellite haplotypes were defined for CF and normal alleles. The mutational spectrum and the associated haplotypes described for the first time in this study should prove relevant for genetic counselling and CF population screening in Brazil. Moreover, our results suggest the presence of a major Mediterranean component in the contemporary Brazilian CF patient pool.

[A new method of ostial revascularization of digestive and renal arteries in complex obstructive aortic pathology]

A new method of revascularization of digestive and renal arteries is reported in this paper, accomplished through the intra-aortic or ostial root, in a 53-year old woman, with the diagnosis of thrombotic occlusion of the terminal aorta associated to a protuberant and calcified lesion of the supraceliac aorta ("coral reef"). The procedure consisted in the implantation of a bifurcated prosthesis from the descending thoracic aorta to both common iliac arteries, through the diaphragm, followed by a longitudinal aortotomy aimed at the removal of the "coral reef" lesion and revascularization of renal, mesenteric and celiac arteries, by means of additional prosthesis placed between the bypass graft and the ostia of these arteries. The left renal artery was reattached to the bypass graft. Visceral ischemic times were short. The post operative course was uneventfull. Two months later, an angio-CT disclosed the complex procedure of revascularization working in excellent condition. The advantages of this new method of revascularization of abdominal visceral arteries in complex obstructive aortic pathology are analysed and discussed.

Effects of phospholipid vesicles (liposomes) on cAMP levels in the rat cerebral cortex

We studied the effects of two types of liposomes (cholate-free liposomes and cholate-containing liposomes) on control (in the presence of 3-isobutyl-1 methyl xanthine [IBMX], a phosphodiesterase inhibitor) and stimulated (IBMX plus isoprenaline) cyclic 3',5'-adenosine monophosphate (cAMP) accumulation in slices of rat cerebral cortex. Our purpose was to examine whether or not liposomes with different lipid constituents modify levels of cAMP in vitro. Liposomes at low concentrations had a significant inhibitory effect on cAMP accumulation in brain tissue. This inhibition was concentration-dependent. Cholate-containing liposomes had a greater inhibitory effect at higher concentrations. Liposomes also inhibited cAMP accumulation in a dose-dependent manner when the tissues were preincubated with ouabain, a Na(+)-K(+)-ATPase inhibitor. These results demonstrate that, in rat brain, liposomes alone modified important biochemical responses such as the adenylyl cyclase-cAMP system coupled to beta-adrenoceptors. The significance of these findings for the mechanism of the action of liposomes is discussed.

Testicular CFTR splice variants in patients with congenital absence of the vas deferens

The involvement of the five thymidine (5T) variant in intron 8 of the cystic fibrosis membrane regulator (CFTR) gene in congenital bilateral absence of the vas deferens (CBAVD) phenotype has been extensively demonstrated. This variant leads to alternative splicing of the CFTR gene which results in a wild-type transcript and one without exon 9. Little is known about expression of the CFTR gene in the testis. We analysed the level of the aberrantly spliced transcripts in testicular biopsies and correlated it with disease expression. Quantitative RT-PCR analysis in testicular biopsies from control and CBAVD patients showed a correlation between the length of the IVS8-6(T) n tract and the level of alternatively spliced transcripts. Results from histological analysis also suggest an involvement of the alternative transcript in the spermatogenic status of patients, leading to a decreased number of mature sperm forms in the tubule.

Characterization of recombinant hepatitis B surface antigen using surface plasmon resonance

Two commercial monoclonal antibodies were shown to interact with distinct epitopes within the major antigenic a determinant region of yeast recombinant hepatitis B surface antigen (rHBsAg) particles, contained in the hepatitis B vaccine, by using the surface plasmon resonance phenomenon on a BIAcore system. Apparent avidity for these antibodies were compared among different rHBsAg batches, showing the consistency of these epitopes. Furthermore, the effect of the alteration of these epitopes, achieved by chemical modifications, was readily reflected by changes in the apparent avidity for these antibodies. The procedures used in the present study provide a novel and efficient way to characterize rHBsAg particles present in different hepatitis B vaccine products.

Prenatal diagnosis of cystic fibrosis in a highly heterogeneous population

Cystic fibrosis (CF) is the most common autosomal recessive disease in Caucasian populations. The Spanish CF population is highly heterogeneous, with more than 70 different mutations causing CF. Since the CFTR gene was cloned, we have performed 81 prenatal diagnoses for 74 couples. Sixty-nine cases had a high risk (1/4) for CF and 12 presented a lower risk (1/240). Direct analysis was possible in 36 cases (44.4 per cent); it was necessary to combine mutation analysis with polymorphic markers in 24 cases (29.6 per cent); mutation analysis and microvillar enzymatic (MVE) analysis were combined in five cases (6.1 per cent); and in 16 cases (19.8 per cent), only indirect analysis was possible. Nine different mutations were detected in this series of families: 621 + 1G -> T, delta F508, 1609delCA, G542X, G551D, 1949del84, R1162X, W1282X, and N1303K. Another ten mutations were identified in these samples after prenatal diagnosis (1811 + 1.6kbA -> G, 711 + 1G -> T, 2869insG, G85E, 2176insC, delta I507, 3272-26A -> G, Q890X, R1066C, and 4005 + 1G -> A). Our current strategy for molecular diagnosis of CF in the Spanish population is based, as a first step, on direct analysis for the two most frequent mutations (delta F508 and G542X) and indirect analysis using the intragenic markers IVS8CA, IVS17BTA, and IVS17BCA. The second step consists of screening for the mutations already associated with the CFTR microsatellite haplotypes. The third step is a specific search for unknown mutations. While actual diagnostic methods are not automatic and robust enough for heterogeneous populations, the diagnostic strategy outlined provides rapid, accurate, and reliable prenatal diagnosis for the majority of couples.

Description of a new quotient that may differentiate blood pressure profiles in essential versus Cushing's syndrome-related hypertension

Since the presence or absence of a nocturnal decrease in blood pressure values (BP) may suggest an increased risk of visceral complications or the existence of secondary hypertension, several methods have been described for evaluating the BP profile. Nevertheless, a universally accepted system to evaluate this item has not yet been established. Our aim in this study was to test different dispersion quotients (DQ) which estimate the differences between the mean of each hour, and the mean of all the readings in the 24 h period. These quotients may be employed regarding systolic (SBP) or diastolic (DBP) blood pressure, and may be referred to the whole period of 24 h, or to the subperiods morning (m), afternoon (a) or night (n). We have studied two non selected groups of essential (n = 20) or secondary (Cushing's syndrome, n = 17) hypertensives. We observed a marked decrease in these quotients, particularly DQ-SBP and nDQ-SBP, in secondary hypertensives (respectively 10.2 +/- 2.9 vs 15.6 +/- 4.2 and 11.8 +/- 5.0 vs 20.5 +/- 6.3, p < 0.0001), thus indicating, a blunted nocturnal fall of BP in these patients. Also the DQ and particularly DQ-SBP, nDQ-SBP and nDQ-DBP, showed a high positive and negative predictive value, sensitivity and specificity for pertaining to the Cushing's syndrome group (respectively: 0.75, 0.88, 0.88, 0.75; 0.86, 0.82, 0.77 0.90; and 0.78, 0.84, 0.82, 0.80).

Ambulatory blood pressure monitoring in physicians working in a hospital: is there an increase in the number of subjects with high workplace blood pressures?

Sixty-two physicians from our hospital who were normotensives, as supported by casual blood pressure measurements, underwent 24-h blood pressure monitoring which included their normal work, home rest and sleep periods. During working hours, 19% of the subjects showed mean diastolic and/or diastolic plus systolic blood pressures higher than those admitted as normal by the WHO for casual measurements for out of work subjects. Both mean systolic and diastolic blood pressure measurements, during the work at the hospital, were significantly higher in males (P < 0.01 and P < 0.005, respectively) than the mean of the readings obtained during the 24-h period, but this phenomenon did not occur among the females. Male's mean systolic (129.8 +/- 10.6 vs. 117.1 +/- 9.7 mmHg, P < 0.0001) and diastolic pressures (83.4 +/- 8 vs. 74.9 +/- 7.3 mmHg, P < 0.001) were significantly higher during the working period in relation to those of the female group. Discussing the influence of the kind of work on blood pressure, we came to the conclusion of the existence in our environment of a group of subjects (generally males), presenting high blood pressure values during their working period at the hospital and normal or borderline values during the rest of the day. This should be of interest, since it has been reported that subjects with high workplace blood pressure have an increased risk of hypertension and target-organ damage.

[Introducing patient-controlled analgesia in a private hospital]

Patient controlled analgesia (PCA) is now a well recognized technique for postoperative analgesia. This study reports an experience of 24 months with 768 patients in a French private hospital. The first step was to train the team for this new technique. The second step was to agree on standards of prescription and safety monitoring rules (respiratory rate plus sedation score), as well as on the selection of patients. Analgesia was obtained with self administrated bolus plus a constant infusion (0.5 milligram per hour) of morphine in all patients, and in some with an addition of paracetamol or ketoprofene for a sparing effect on morphine consumption. All patients were returned to their ward, after an initial titration of pain treatment in the recovery room. No major problems occurred during the study period. In 13 patients the respiratory rate decreased to or under 10 c.min-1 without increased sedation and for safety reasons, the PCA was discontinued. PCA is now routinely used postoperatively for a majority of painful procedures in our institution.

Calcium-dependent release of norepinephrine from permeabilized PC12 cells is inhibited by approximately 48 and approximately 112 kDa fragments of botulinum neurotoxin type E

Permeabilized PC12 cells exhibit a Ca(2+)-stimulated norepinephrine secretory pathway which is sensitive to botulinum neurotoxin serotypes A, B and E [Lomneth R., Martin T.F.J. and DasGupta B. R. (1991) J. Neurochem. 57: 1413-1421]. Two novel amino terminal fragments of the 150 kDa neurotoxin serotype E (approximately 112 and 48 kDa), produced by digestion with pepsin, were tested in permeabilized PC12 cells. The intracellular inhibitory activity of the approximately 112 kDa amino terminal fragment, like that of the 150 kDa neurotoxin, was progressively enhanced after trypsinization and dithiothreitol reduction. The approximately 50 kDa C-terminal half of the heavy chain therefore does not contribute to the enhancement of inhibitory activity. The approximately 48 kDa amino terminal light chain-like fragment completely inhibited release of norepinephrine, with an IC50 = 500 pM (more potent than the light chain isolated after digestion with trypsin) not requiring reduction with dithiothreitol. These results clarify the molecular basis of activation of neurotoxin by trypsin and dithiothreitol.