Evaluating soil moisture retrievals from ESA's SMOS and NASA's SMAP brightness temperature datasets.

Two satellites are currently monitoring surface soil moisture (SM) using L-band observations: SMOS (Soil Moisture and Ocean Salinity), a joint ESA (European Space Agency), CNES (Centre national d'études spatiales), and CDTI (the Spanish government agency with responsibility for space) satellite launched on November 2, 2009 and SMAP (Soil Moisture Active Passive), a National Aeronautics and Space Administration (NASA) satellite successfully launched in January 2015. In this study, we used a multilinear regression approach to retrieve SM from SMAP data to create a global dataset of SM, which is consistent with SM data retrieved from SMOS. This was achieved by calibrating coefficients of the regression model using the CATDS (Centre Aval de Traitement des Données) SMOS Level 3 SM and the horizontally and vertically polarized brightness temperatures (TB) at 40° incidence angle, over the 2013 - 2014 period. Next, this model was applied to SMAP L3 TB data from Apr 2015 to Jul 2016. The retrieved SM from SMAP (referred to here as SMAP_Reg) was compared to: (i) the operational SMAP L3 SM (SMAP_SCA), retrieved using the baseline Single Channel retrieval Algorithm (SCA); and (ii) the operational SMOSL3 SM, derived from the multiangular inversion of the L-MEB model (L-MEB algorithm) (SMOSL3). This inter-comparison was made against in situ soil moisture measurements from more than 400 sites spread over the globe, which are used here as a reference soil moisture dataset. The in situ observations were obtained from the International Soil Moisture Network (ISMN; https://ismn.geo.tuwien.ac.at/) in North of America (PBO_H2O, SCAN, SNOTEL, iRON, and USCRN), in Australia (Oznet), Africa (DAHRA), and in Europe (REMEDHUS, SMOSMANIA, FMI, and RSMN). The agreement was analyzed in terms of four classical statistical criteria: Root Mean Squared Error (RMSE), Bias, Unbiased RMSE (UnbRMSE), and correlation coefficient (R). Results of the comparison of these various products with in situ observations show that the performance of both SMAP products i.e. SMAP_SCA and SMAP_Reg is similar and marginally better to that of the SMOSL3 product particularly over the PBO_H2O, SCAN, and USCRN sites. However, SMOSL3 SM was closer to the in situ observations over the DAHRA and Oznet sites. We found that the correlation between all three datasets and in situ measurements is best (R > 0.80) over the Oznet sites and worst (R = 0.58) over the SNOTEL sites for SMAP_SCA and over the DAHRA and SMOSMANIA sites (R= 0.51 and R= 0.45 for SMAP_Reg and SMOSL3, respectively). The Bias values showed that all products are generally dry, except over RSMN, DAHRA, and Oznet (and FMI for SMAP_SCA). Finally, our analysis provided interesting insights that can be useful to improve the consistency between SMAP and SMOS datasets.

Plasma acyl-ghrelin increases after meal initiation: a new insight.

BACKGROUND/OBJECTIVES: Plasma ghrelin secretion over time in humans is characterized by pre-prandial increases and by post-prandial decreases all day long. However, some authors who measured ghrelin concentrations around meals showed a rise in plasma ghrelin concentration after meal initiation followed by the typical post-prandial decrease. In order to confirm this observation that has never been discussed, we described ghrelin profiles around four eating episodes in the morning in adult men. SUBJECTS/METHODS: Twenty normal-weight and 17 obese men were instructed to eat four fixed meals (706 kJ) 10 min long at 0800 h, 0900 h, 1000 h and 1100 h. Using frequent blood sampling, we determined plasma acyl-ghrelin concentrations around those eating episodes. Glucose, insulin and GLP-1 concentrations were also measured. RESULTS: The meals consumption induced a significant increase in plasma acyl-ghrelin concentrations 10 min after meal initiation (P<0.0001): +20.9±5.8 and +10.7±3.3 pg/ml in normal-weight and obese subjects for the first meal; +10.4±3.0 and +5.5±3.9 pg/ml in normal-weight and obese subjects for the second meal; +12.4±3.6 and +4.2±2.1 pg/ml in normal-weight and obese subjects for the third meal; and +4.4±4.1 and +3.3±2.61 pg/ml in normal-weight and obese subjects for the fourth meal. CONCLUSIONS: This study is the first to describe and discuss the post-meal initiation ghrelin increase. This finding is consistent in normal-weight and obese individuals.

[Value of the Remedi chromatography automate for the analytic diagnosis of drug poisoning]. / Intérêt de l'automate de chromatographie Remedi pour le diagnostic analytique des intoxications médicamenteuses.

The aim of this study was to evaluate the liquid chromatographic system Remedi (Biorad) in comparison with traditional immunological and colorimetric methods, for the diagnosis of acute drug overdose. 469 blood samples and 95 stomach cleaning liquid samples have been analysed during 1995. The usual toxicologic analysis was composed of the benzodiazepines, tricyclic antidepressants and barbiturates research. Ethanol, meprobamate and acetaminophen assays were performed only on physician's request. Only three pharmacological classes can be analysed both with immunological methods and Remedi: benzodiazepines, tricyclic antidepressants and barbiturates. Remedi has been found to be less sensitive than immunological method for benzodiazepines, it sometimes gave false negative results for barbiturates, but it was very efficient for antidepressants. Remedi often identified drugs other than the 3 previous classes: sedatives, antipsychotic, beta-blockers, antiarythmics. Furthermore these drugs are of clinical importance due to the fact that they are able to modify the symptomatology. In every case Remedi was able to give an estimation of the blood concentration of the toxic molecule matched. Remedi can not replace traditional methods but is a good complementary tool, available in emergency. This is particularly useful when clinical signs do not correspond to the toxics suspected by questioning the patient or relatives.

[Evaluation of an automated liquid chromatograph permitting toxicologic screening of biological fluids]. / Evaluation d'un automate de chromatographie liquide permettant un screening toxicologique dans les liquides biologiques.

This study evaluated an automated high performance liquid chromatography algorithm that allows identification of 330 substances and metabolites in biological fluids. We assessed its ability to detect in urine and gastric lavage fluids the main psychotropic drugs ingested with suicidal intent. Antidepressants and most of the phenothiazines were recognised; identification of benzodiazepines was more uncertain. Compared to EMIT techniques, chromatography is less sensitive, but allows precise identification of the offending poison, quantifies the amount, and allows broad toxicological screening of pharmacological classes inaccessible to the EMIT technique.

[Evaluation of Emit netilmicin and amikacin assays on Dimension RXL HM (Dade Behring) open channels]. / Adaptation des trousses Emit nétilmicine et amikacine sur canaux ouverts du Dimension RXL HM (Dade Behring).

The aim of this study was to evaluate and to validate an enzyme immunoassay in homogeneous phase for netilmicin and amikacin, adapted on the Dimension RXL HM (Dade Behring) machine. The results were compared with those obtained with automated polarization of fluorescence immunoassay using TDx FLx (Abbott). The protocol of the study and the analytical criteria were inspired by the protocol Valtec version 2002 recommended by the French Society of Clinical Biology (SFBC). The validation of this technique as adapted to the Dimension RXL HM has allowed its use for routine dosage adjustment of amikacin and netilmicin. The practicability is however the weak point of the adaptation of these techniques, even limiting as for their implementation.

[Critical analysis of different methods used for toxicology screening in emergency laboratory]. / Analyse critique des différentes méthodes utilisées pour le dépistage toxicologique dans un laboratoire d'urgence.

Emergency analysis in toxicology is a difficult exercise. It involves in diagnosis, prognosis and the treatment of intoxication. Several methods exist in emergency screening. We have distinguished three large groups. Based on specificity: screening methods of medicament family (chemical methods and immunoassays) with benzodiazepines, tricyclic antidepressants, barbiturates and phenothiazines; complementary screening methods (thin layer chromatography and high pressure liquid chromatography) for a wider screening and finally quantitative methods (enzymatic, immunoassay, spectrometry and chromatography) specific to a molecule. The first group allows a rapid qualitative research according to medicament class but lacks specificity. The second group represented by the Remedi system, offers a larger screening of molecules but is more expensive and cannot detect classic molecules. The third group allows a precise dosage but is restricted to one molecule. We need one or the other of methods following clinical context and the type of molecule. In our laboratory, we have eliminated barbiturates and benzodiazepines research. We search only tricyclic antidepressants, salicylates and paracetamol. The Remedi system acts as a complement. It is essential to have a good knowledge of the limits and specificity of each method in order to allow the clinician to see the interpretation of the given result. The execution period and the quality of analytical result depend on dialogue between analyst and clinician before and after analysis.

[Compared diagnostic performances of CKMB measurements by immuno-inhibition and three immunoenzyme methods for the early diagnosis of myocardial infarction]. / Performances diagnostiques comparées des mesures de la CKMB par immuno-inhibition et par trois méthodes immunoenzymologiques pour le diagnostic précoce de l'infarctus du myocarde.

In 98 patients consecutively admitted in a medical intensive care unit, an aliquot taken from the blood sample withdrawn for the cardiac enzyme admission request has been frozen. After thawing of these 98 aliquots total CK and the creatine kinase MB isoenzyme were measured on the same day. For this last determination, four methods were used and compared: an immunoinhibition method (Merck) and three immunoenzymatic assays (Abbott on IMX; Baxter on Stratus II; Hybritech on single use Icon cylinder). In 19 out of the 98 patients studied the diagnosis of myocardial infarction was made retrospectively by a cardiologist. This diagnosis was established according to the criteria defined by the WHO. The clinical performances (sensitivity, specificity, positive predictive value, negative predictive value) have been calculated for each test according to the following criteria: on the one hand, a cut-off of 8% (reference range of our laboratory) for the immunoinhibition technique; on the other hand, a cut-off defined by the manufacturer together with a cut-off obtained from the ROC curves for the three immunoenzymatic assays. Our results clearly demonstrate that the clinical performances of the three immunoenzymatic CKMB assays are very comparable and appear to be much better than the immunoinhibition method which should be abandoned.

[Surgical risk of transfusion in a French Universitary Hospital]. / Cartographie du risque d'être transfusé en chirurgie au CHU de Lyon : un outil de rationalisation de la prescription des examens immunohématologiques (Hospices civils de Lyon - HCL).

INTRODUCTION: Immunohaematology examinations are usually prescribed preoperatively according to more or less standardized protocols. We wanted to assess the relevance of these protocols on the basis of factual data: an overview of the rate of transfusions carried out as part of surgery within the HCL in 2009. STUDY DESIGN: The list of patients operated in 2009 in the HCL (IPOP by Cristalnet) has been combined with the list of patients transfused in the same time period (CTS server, Inlog). The percentage of patients transfused during the stay, and the percentage of patients transfused on the day of the intervention itself were determined for each type of surgery. The study focused on 13,571 patients affected by 44 surgeries. PATIENTS AND METHODS: Six hundred and thirty-three patients were transfused, 45% of them the day of the intervention. The risk of needing to carry out a transfusion depends on the risk to the patient and surgery. For example, the total hip arthroplasty transfusion risk is 11.9% when it's programmed against 37.8% in emergency surgery. The transfusion risk of knee arthroscopies, osteosynthesis of wrist fracture, carpal canal surgeries and of appendectomies, thyroidectomies, herna repair surgeries are below 0.5%. The transfusion risk of colectomy is 18.1%. Thus, new recommendations for good clinical practices on the relevance of settled surgery-preoperative immunohematologic exams can be established. CONCLUSION: The emergency degree of the transfusion must be taken into account for such recommendation. Each hospital should perform its own cartography to justify its own protocols.

Biochemical modifications in the blood and the heated fluids during intraperitoneal chemohyperthermia.

The biochemical changes in blood during intraperitoneal chemohyperthermia (IPCH) were examined by carrying out complete assessments before and after the operation. These assessments were made up of 23 parameters: Na, K, Cl, CO2, urea, creatinine, proteins, glucose, calcium, phosphates, magnesium, bilirubin, uric acid, lactic acid, CRP, ASAT, ALAT, CK, LDH, gamma-GT, ALP, lipase, and amylase. Only 5 of these parameters showed significant changes: proteins, urea, ALP, gamma-GT, lactic acid. The protein and urea levels decreased due to hemodilution induced by the perfusion of fluids. ALP and gamma-GT levels decreased, possibly due to localized inhibition of secretion. Lactic acid levels increased due to the movement of lactates from the heated fluid into the blood. The study of biochemical changes within the heated fluids was made using the following parameters: CA 125, CA 19-9, CEA, ASAT, ALAT, CK, LDH, gamma-GT, ALP, lipase, uric acid, phosphates, proteins, Na, K, Cl, urea, creatinine, and magnesium. Between the beginning and the end of IPCH, significant increases were found in the levels of CA 125 (+173%), proteins (+190%), ASAT (+130%), LDH (+103%), K+ (+232%), PO4 (+134%), and uric acid (+99%). These increases indicate the existence of a significant degree of cellular lysis.