Multiparameter optimisation of a magneto-optical trap using deep learning.

Machine learning based on artificial neural networks has emerged as an efficient means to develop empirical models of complex systems. Cold atomic ensembles have become commonplace in laboratories around the world, however, many-body interactions give rise to complex dynamics that preclude precise analytic optimisation of the cooling and trapping process. Here, we implement a deep artificial neural network to optimise the magneto-optic cooling and trapping of neutral atomic ensembles. The solution identified by machine learning is radically different to the smoothly varying adiabatic solutions currently used. Despite this, the solutions outperform best known solutions producing higher optical densities.

Return to work after general surgery: A comparative study.

PURPOSES: There is scarce information on the time to return to work after general surgery. The aim of this study was to analyze time off work after elective cholecystectomy and to compare the results with those in patients undergoing other surgical interventions. METHODS: Observational and comparative study. Inclusion criteria were: being of working age and undergoing elective laparoscopic cholecystectomy (group 1) or unilateral inguinal hernia or haemorrhoidectomy (group 2). RESULTS: 36 patients were included: 18 patients in each group. Overall, return to work occurred at a mean of 35.7 days, with no significant differences (p=0.656) between groups (group 1: 36.6 days vs. group 2: 35.44 days). The reasons for not returning to work earlier were fear of complications (37.5%), pain control (37.5%), surgeon recommendation (12.5%), and general practitioner recommendation (12.5%). CONCLUSIONS: Time to recovery after laparoscopic cholecystectomy is prolonged. No statistically significant differences with less complex surgical procedures were detected.

Blood lactate levels are superior to oxygen-derived variables in predicting outcome in human septic shock.

Recent reports have shown that oxygen delivery (Do2) and oxygen uptake (Vo2) could be related to outcome of critically ill patients. In this study, we examined measurements of cardiac output, oxygen-derived variables, and blood lactate levels in 48 patients with documented septic shock. There were 27 survivors and 21 nonsurvivors from the shock episode. For all 174 observations, there was a significant linear relationship between Vo2 and Do2 (Vo2 = 79 + 0.17 x Do2, r = 0.64, p less than 0.001). There were no significant differences in Do2 between survivors and nonsurvivors at the onset of septic shock (mean +/- SD, 540 +/- 219 vs 484 +/- 222 ml/min.m2, NS) or in the final phase of septic shock (506 +/- 163 vs 443 +/- 187 ml/min.m2, NS). Also, no significant differences were found in Vo2 and oxygen extraction between survivors and nonsurvivors. However, survivors had significantly lower blood lactate levels both initially (5.1 +/- 2.7 vs 8.2 +/- 5.4 mmol/L, p less than 0.05) and in the final phase of septic shock (2.6 +/- 1.9 vs 7.7 +/- 5.6 mmol/L, p less than 0.001). Only the survivors had a significant decrease in blood lactate levels during the course of septic shock (p less than 0.001). We conclude that the oxygen-derived variables, Do2 and Vo2, cannot be used as prognostic indicators in human septic shock. In contrast, blood lactate levels are closely related to ultimate survival from septic shock. Furthermore, decreases in blood lactate levels during the course of septic shock could indicate a favorable outcome. Therefore, blood lactate levels can serve as a reliable clinical guide to therapy.

Veno-arterial carbon dioxide gradient in human septic shock.

Recent reports have shown that venous hypercarbia, resulting in a widening of the veno-arterial difference in PCO2 (dPCO2), is related to systemic hypoperfusion in various forms of low-flow state. Although septic shock usually is a hyperdynamic state, other factors can influence the CO2 production and elimination, and thus dPCO2 in septic shock This study examined the dPCO2 and acid-base balance together with cardiac output measurements and oxygen-derived variables in 64 adult patients with documented septic shock. For a total of 191 observations, a significant exponential relation between dPCO2 and CO was found. At time of first measurement, 15 patients had an increased dPCO2 (above 6 mm Hg) and a higher mixed venous PCO2 (PvCO2) (47.2 +/- 10.0 vs 35.9 +/- 7.3 mm Hg, p less than 0.001). These patients had a lower cardiac index (2.9 +/- 1.3 vs 3.8 +/- 2.0 L/min.m2, p less than 0.01), a higher oxygen extraction ratio, but a similar VO2 than patients with normal dPCO2. The higher dPCO2 could also be related to an impaired CO2 elimination as indicated by a higher PaCO2 and a lower PaO2/FIO2 in these patients. Nonsurvivors had a significantly higher dPCO2 than survivors (5.9 +/- 3.4 vs 4.4 +/- 2.3 mm Hg, p less than 0.05) in the presence of similar cardiac output. The higher dPCO2 in these patients was probably related to the higher blood lactate levels (7.7 +/- 5.3 mmol/L vs 4.5 +/- 2.8 mmol/L, p less than 0.01) and the more severe pulmonary impairment (SaO2 90 +/- 8 percent vs 95 +/- 4 percent, p less than 0.001). Arteriovenous oxygen content difference (dAVO2) and VO2 were similar in survivors and nonsurvivors. In conclusion, dPCO2 patients with septic shock is related principally to cardiac output but apparently also to the degree of pulmonary impairment. Although dPCO2 is larger in nonsurvivors, its prognostic value is modest.

Myocardial depression characterizes the fatal course of septic shock.

The relationship between cardiac and vascular abnormalities was studied in 68 patients with established septic shock. At time of hemodynamic evaluation, after initial resuscitation, there was no significant difference in arterial pressure, pulmonary artery pressure, cardiac filling pressures, and cardiac index between the 38 survivors of shock and the 30 patients who died of shock, but the left ventricular stroke work index and the right ventricular (RV) stroke work index were higher in survivors than in those who died (mean +/- SD: 25.0 +/- 9.1 vs 20.1 +/- 9.4 gm/m2 [p less than 0.05] and 6.6 +/- 3.6 vs 4.8 +/- 2.8 gm/m2 [p less than 0.05], respectively). Survivors had also higher thermodilution RV ejection fraction and lower RV end-diastolic volumes than had those who died (43.9% +/- 16.3% vs 31.1% +/- 13.7% [p less than 0.01] and 82 +/- 30 vs 99 +/- 31 ml/m2 [p less than 0.05], respectively). Calculated systemic vascular resistance was similar in the two groups, but vasopressors had been required in 22 (58%) of 38 survivors and 25 (83%) of 30 patients who died (p less than 0.01). Moreover, when the patients were separated into two groups according to their cardiac output, higher or lower than 3 L/min/m2, in both subgroups patients who died had lower blood pressure than had survivors. Blood lactate levels were significantly lower in survivors than in nonsurvivors (5.1 +/- 2.1 vs 8.1 +/- 4.7 mEq/L, p less than 0.01). Final data obtained before recovery of shock or death indicated that the survivors had higher arterial pressure, lower pulmonary artery pressure and right atrial pressure, higher stroke volume, and higher RV ejection fraction than had the patients who died. No survivors but all patients who died had been treated with vasopressors. These data therefore indicate that death as a result of septic shock is characterized by both myocardial depression and altered vascular tone and both are probably interrelated.

Does peripheral hypocaloric parenteral nutrition benefit the postoperative patient? Results of a multicentric randomized trial.

To study the potential benefits of hypocaloric peripheral parenteral nutrition (HPPN) in medium to high risk surgical patients we compared this regimen with standard fluid therapy during the postoperative period. Seventy patients were randomised to receive HPPN, consisting of 1 g of amino acids and 2 g of polyols (sorbitol and xylitol) per Kg per day (n = 41), or 1500 ml of 5% glucose and 1500 ml of saline (n = 29). There were no differences in length of hospital stay, postoperative complications or weight loss between the two groups. Concentrations of short and long half-life plasma proteins were similar in both groups. Nitrogen balance was negative and the nitrogen retention was low (60%) in the HPPN group. We conclude that there are no discernible clinical advantages in giving HPPN postoperatively to patients undergoing medium or major severity elective surgery.

Serial blood lactate levels can predict the development of multiple organ failure following septic shock.

BACKGROUND: Despite successful initial resuscitation, septic shock frequently evolves into multiple system organ failure (MSOF) and death. Since blood lactate levels can reflect the degree of cellular derangements, we examined the relation between serial blood lactate levels and the development of MSOF, or mortality, in patients with septic shock. PATIENTS AND METHODS: In 87 patients with a first episode of septic shock, we measured initial lactate (at onset of septic shock), final lactate (before recovery or death), "lactime" (time during which blood lactate was > 2.0 mmol/L, and the area under the curve (AUC) for abnormal values (above 2.0 mmol/L). These measurements were correlated with survival and organ failure and scored for four systems (ie, respiratory, renal, hepatic, and coagulation), adding to a maximal score of 8. RESULTS: Thirty-three (38%) patients survived. Of the 54 (62%) nonsurvivors, the 13 patients who died during the first 24 hours of septic shock had higher initial blood lactate levels than those who died later (mean +/- standard deviation 9.6 +/- 5.3 mmol/L versus 5.6 +/- 3.7 mmol/L, P< 0.05). The 74 patients who survived the first 24 hours of shock, were studied in more detail. On presentation, survivors had a significantly higher mean arterial pressure (76 +/- 12 mm Hg versus 63 +/- 20 mm Hg, P < 0.001) and arterial pH (7.40 +/- 0.07 versus 7.37 +/- 0.09, P< 0.05) than nonsurvivors. Although the differences in initial blood lactate levels between survivors and nonsurvivors did not reach statistical significance (4.7 +/- 2.5 mmol/L versus 5.6 +/- 3.7 mmol/L), only the survivors had a significant decrease during the first 24 hours of septic shock. The survivors had a significantly lower lactime and AUC than the nonsurvivors. The duration of lactic acidosis was the best predictor of survival (multiple regression analysis, R2 = 0.266, P <0.001), followed by age, heart rate, and mean arterial pressure. Patients with lower organ failure scores had lower initial blood lactate, lactime, and AUC. The duration of lactic acidosis was the only significant predictor of organ failure. CONCLUSIONS: In patients with septic shock, serial determinations of blood lactate levels are good predictors of the development of MSOF an death. In this respect, the duration of lactic acidosis is more important than the initial lactate value. Although a number of factors may contribute to hyperlactatemia, these observations are compatible with a direct role of prolonged tissue hypoxia in the development of complications following septic shock.

[Persistent left superior vena cava. Apropos of 2 cases]. / Veine cave supérieure gauche persistante. A propos de deux observations.

Double superior vena cava with persistence of a left superior vena cava is rarely encountered. The prevalence in the general population is 0.3% but may reach 3 to 10% in patients with inborn heart diseases. There are usually no clinical signs and the malformation is usually discovered fortuitiously. We describe the features of two cases observed in our institution and reviewed the literature on the subject.

[Leukemoid reaction and hypercalcemia in carcinoma of the bladder]. / Réaction leucémoïde et hypercalcémie au cours d'un carcinome de la vessie.

A 76 year-old man with urothelial carcinoma of the bladder presented marked leucocytosis (69,300 mm3) and hypercalcemia (15.4 mg/mm3). The paraneoplastic origin of these observations was demonstrated. The authors review other reported cases and discuss the pathogenic factors and the mechanisms of this paraneoplastic association.

[Waiting list in general and digestive surgery: patient expectations, quality of life during waiting time and overall satisfaction]. / Lista de espera en Cirugía General y Digestiva: expectativas del paciente, calidad de vida durante la espera y grado de satisfacción.

INTRODUCTION: The structural resources of the National Health system are limited, and therefore early surgery cannot be performed on all patients. The objective was to analyse the satisfaction perceived by the patient as regards the delay of treatment by waiting list of three types of surgery. The influence of expectations on waiting times, and impaired quality of life due to the clinical symptoms during the delay, were studied. MATERIAL AND METHODS: A prospective study was conducted using a postal questionnaire. We compared the expectations (scale of 1 to 5), the impact on quality of life for symptoms (scale of 1 to 5) and the level of patient satisfaction (scale of 1 to 5) with respect to time on the waitng list for cholelithiasis, inguinal hernia and haemorrhoids. The predictors of patient dissatisfaction were analysed. RESULTS: A total of 57 patients were included. When comparing the characteristics of patients with and without satisfaction over time on the waiting list, days on the waiting list (P=.044), the change in the quality of life due to the symptoms (P=.028), and expectations (P<.001) were significantly different between the two groups. In the multivariate analysis, the expectation was associated with patient dissatisfaction as regards the time on waiting list (OR: 3.14 95% CI: 5.91 to 220.73, P<.001). CONCLUSIONS: The level of patient dissatisfaction is associated with expectations about time in waiting list.

Once-daily, 3-day azithromycin versus a three-times-daily, 10-day course of co-amoxiclav in the treatment of adults with lower respiratory tract infections: results of a randomized, double-blind comparative study.

A 3-day regimen of azithromycin (500 mg once daily) and a 10-day regimen of co-amoxiclav (625 mg three times daily) were compared in a double-blind study of 67 patients with acute infectious exacerbations of chronic bronchitis (AIECBs, n = 54), acute bronchitis (n = 7), or pneumonia (n = 6). In patients treated with azithromycin, satisfactory clinical responses (cure or improvement) were seen in 24/28 (86%) patients with AIECBs, 2/4 (50%) with acute bronchitis and 2/2 (100%) with pneumonia. Responses were satisfactory in 24/26 (92%), 4/4 (100%) and 4/4 (100%) patients, respectively, receiving co-amoxiclav. Streptococcus pneumoniae and Haemophilus influenzae were the commonest pathogens isolated at baseline. At the end of treatment, baseline pathogens were eradicated in 9/10 microbiologically-assessable patients treated with azithromycin and in 10/10 treated with co-amoxiclav. Adverse events related or possibly related to treatment occurred in five patients in each treatment group; the majority of these events affected the gastrointestinal system. One patient in each treatment group discontinued therapy because of adverse events. The study, therefore, demonstrates that 500 mg azithromycin administered once daily for 3 days is as efficacious and well tolerated as co-amoxiclav given three times daily for 10 days in the domiciliary treatment of adults with acute lower respiratory tract infections.

Antiglomerular basement membrane nephritis induced by IgA1 antibodies.

A 62-year-old man was admitted for acute renal failure due to crescentic rapidly progressive glomerulonephritis. Kidney biopsy showed intense staining for IgA, IgA1 and C3 in a linear pattern along the glomerular basement membrane (GBM). Serologic tests for detecting anti-GBM antibodies were positive for IgA class and IgA1 subclass and negative for IgG and IgA2. Serum IgA anti-GBM antibodies appeared essentially in the polymeric form, an observation in agreement with recent studies demonstrating polymeric IgA response after parenteral immunization. There was no sign of pulmonary involvement. This patient is the first to present with an isolated nephritis due to anti-GBM antibodies restricted to the IgA class (IgA1 subclass). Routine tests for circulating anti-GBM antibodies should also include the IgA class.

Coxsackie B3 virus: an unusual cause of unilateral mediastinal nodal enlargement.

We report on a patient with febrile illness, right unilateral paratracheal widening, pulmonary infiltrates, pleural effusions, exanthema and diarrhea. The right paratracheal widening was due to lymph node enlargement confirmed by CT scan. Symptoms disappeared subsequently without specific treatment. On the basis of serological tests, we are able to diagnose a coxsackie B3 virus infection. No previous case report of unilateral mediastinal nodal enlargement contemporary to a coxsackie B3 virus infection was found in our review of the literature.

Autonomic dysreflexia after spinal cord transection or compression in 129Sv, C57BL, and Wallerian degeneration slow mutant mice.

To study plasticity of central autonomic circuits that develops after spinal cord injury (SCI), we have characterized a mouse model of autonomic dysreflexia. Autonomic dysreflexia is a condition in which episodic hypertension occurs after injuries above the midthoracic segments of the spinal cord. As synaptic plasticity may be triggered by axonal degeneration, we investigated whether autonomic dysreflexia is reduced in mice when axonal degeneration is delayed after SCI. We subjected three strains of mice, Wld(S), C57BL, and 129Sv, to either spinal cord transection (SCT) or severe clip-compression injury (CCI). The Wld(S) mouse is a well-characterized mutant that exhibits delayed Wallerian degeneration. The CCI model is an injury paradigm in which significant the axonal degeneration is due to secondary events and therefore delayed relative to the time of the initial injury. We herein demonstrate that the incidence of autonomic dysreflexia is reduced in Wld(S) mice after SCT and in all mice after CCI. To determine if differences in afferent arbor sprouting could explain our observations, we assessed changes in the afferent arbor in each mouse strain after both SCT and CCI. We show that independent of the type of injury, 129Sv mice but not C57BL or Wld(S) mice demonstrated an increased small-diameter CGRP-immunoreactive afferent arbor after SCI. Our work thus suggests a role for Wallerian degeneration in the development of autonomic dysreflexia and demonstrates that the choice of mouse strain and injury model has important consequences to the generalizations that may be drawn from studies of SCI in mice.

Neisseria sicca pneumonia and bronchiectasis.

Neisseria sicca, although considered a harmless saprophyte, has been recognised as an etiologic agent in three cases of pneumonitis, and rare cases of endocarditis, meningitis, and osteomyelitis, particularly in immunocompromised hosts. We report the case of a 76-year-old man with a community-acquired pneumonia, in whom both sputum samples and bronchial secretions obtained with bronchoscopic protected catheter brush grew pure culture of N. sicca with abundant polymorphonuclear neutrophils. Dramatic clinical improvement only occurred after initiation of an appropriate antibiotherapy according to susceptibility spectrum of the isolated N. sicca. Bronchiectasis underlying lesions were disclosed by computed tomography. N. sicca should be added to the list of commensal organisms able to cause pulmonary infection. Moreover, the association of N. sicca and bronchiectasis has never been published.

Differential gene expression profiles in embryonic, adult-injured and adult-uninjured rat spinal cords.

To identify genes that render the adult-injured spinal cord nonpermissive and the embryonic spinal cord permissive to regeneration, we used subtraction hybridization and suppression PCR to generate subtractive cDNA populations representing (1) genes expressed in the embryonic but not in the adult-injured or uninjured spinal cords, (2) genes expressed in the adult-injured but not in the embryonic or adult-uninjured spinal cords, and (3) genes expressed in the embryonic and adult-injured spinal cords but not in the adult-uninjured spinal cord. Between 85 and 98% of the cDNAs identified are differentially represented in each population. Genes in each cDNA population were identified by microarray hybridization. Genes involved in inflammation, apoptosis, and neuroprotection were overrepresented in injured spinal cord cDNA, whereas genes involved in cell signaling and differentiation were overrepresented in the embryonic cDNA. This gene expression profiling suggests new hypotheses regarding the genes involved in inhibition and promotion of spinal cord regeneration.