Mean Saturation Research Articles

MP20-09 SHOULD BIOPSY-NAIVE PATIENTS BE OFFERED UP-FRONT MULTI-PARAMETRIC MRI (MPMRI) SCAN AND TRANS-PERINEAL MRI-FUSION TARGETED AND SATURATION BIOPSIES?

You have accessJournal of UrologyProstate Cancer: Detection & Screening II (MP20)1 Apr 2020MP20-09 SHOULD BIOPSY-NAIVE PATIENTS BE OFFERED UP-FRONT MULTI-PARAMETRIC MRI (MPMRI) SCAN AND TRANS-PERINEAL MRI-FUSION TARGETED AND SATURATION BIOPSIES? Woon Tsang*, Yu Fei Qiao, Karthik Thandapani, Qing Hui Wu, Bertrand Ang, Wynne Chua, Yee Liang Thian, Lincoln Tan, and Edmund Chiong Woon Tsang*Woon Tsang* More articles by this author , Yu Fei QiaoYu Fei Qiao More articles by this author , Karthik ThandapaniKarthik Thandapani More articles by this author , Qing Hui WuQing Hui Wu More articles by this author , Bertrand AngBertrand Ang More articles by this author , Wynne ChuaWynne Chua More articles by this author , Yee Liang ThianYee Liang Thian More articles by this author , Lincoln TanLincoln Tan More articles by this author , and Edmund ChiongEdmund Chiong More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000853.09AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: EAU guidelines recommended mpMRI scan for prior negative biopsy and was expanded to include biopsy-naïve and AS patients. Strength of recommendation was weak for biopsy-naïve patients. Our aims were to determine clinically significant prostate cancer (CSPC, any GS≥7) rate for biopsy-naïve patients using Trans-perineal MRI-Fusion targeted and saturation biopsy(TP-Fusion-BX)compared to systemic biopsies with trans-rectal(TRUS-BX) and trans-perineal(TP-BX) US-guided biopsies and their complications. METHODS: Between September 2015 to September 2019, 241 patients with an elevated PSA and mpMRI scan were recruited into a prospective study for TP MRI-fusion targeted and saturation biopsies using a robotic-assisted iSR’obot Mona LisaTMbiopsy platform. MRI lesions were classified according to PIRADv2. PIRAD≥3 lesions were targeted. RESULTS: For 241 TP-Fusion-BX patients, 116(48%) were biopsy-naïve, 73(30%) prior negative biopsy and 52(22%) AS:mean age 65years; median PSA 7.32ng/dL; mean target cores 7.44±4.83; mean saturation cores 29.80±10.78 (IQR 12-56 cores). For 178 TRUS-BX patients, median PSA 10.76ng/dL(IQR 0.93–4679), mean cores 11.14±2.92(IQR 2-18 cores). For 117 TP-BX patients, median PSA 12.51ng/dL(IQR 0.30–1000), mean cores 12.99±3.68(IQR 12–18 cores). For biopsy-naïve patients who had TP-Fusion-BX, 55% had prostate cancer and 42% CSPC. 53% prior negative biopsy had cancer, 37% CSPC. For AS 93% had cancer, 56% CSPC. 306 PIRAD lesions ≥3 were targeted and cancer rate was summarised in Table 1. Cancer rate for 3 different biopsy platforms was summarised in Table 2. Using TP-Fusion-BX for biopsy-naïve patients, CSPC was significantly higher compared to TRUS-BX and TP-BX for PSA<10 (p=0.0019). Comparing TRUS-BX with TP-Fusion-BX, PSA<10 (p<0.004) and PSA 10-20 (p=0.0378) were significant. Post biopsy sepsis was low:1.7%TP-Fusion-BX; 0.9%TP-BX and 4.4%TRUS-BX. CONCLUSIONS: CSPC was higher for biopsy-naïve patients for PSA<20 using TP MRI-Fusion biopsy. Thus, an up-front mpMRI scan prior to prostate biopsy be offered to these patients and not restricted to patients with prior negative biopsy. TP MRI-Fusion biopsy with target and saturation biopsies, CSPC was higher compared to non-targeted biopsy and morbidity was less. Source of Funding: NONE © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e310-e310 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Woon Tsang* More articles by this author Yu Fei Qiao More articles by this author Karthik Thandapani More articles by this author Qing Hui Wu More articles by this author Bertrand Ang More articles by this author Wynne Chua More articles by this author Yee Liang Thian More articles by this author Lincoln Tan More articles by this author Edmund Chiong More articles by this author Expand All Advertisement PDF downloadLoading ...

Neuromonitored Thyroid Surgery: Optimal Stimulation Based on Intraoperative EMG Response Features.

To evaluate/compare normative electrophysiologic electromyography (EMG) response characteristics of recurrent laryngeal, vagus, and external branch of superior laryngeal nerve evoked with different stimulators used in neuromonitored thyroid surgery. Prospective crossover study METHODS: EMG responses obtained via endotracheal tube surface electrodes in 11 patients undergoing thyroid surgery were recorded when stimulated with four stimulators: two monopolar (Prass standard and ball tip), one bipolar, and one dissecting instrument. Normative mean EMG results including latency, amplitude, threshold, saturation currents, and distance-sensitivity were compared. The Prass standard stimulator had shorter latency time when nerve was not covered with fascia (P = .04). The bipolar, dissecting instrument, and ball tip demonstrated similar latency times with and without nerve fascia. Pooled mean latency increased significantly from 1.86 ms to 2.16 ms when comparing nerves without fascia and nerves with fascia (P < .05). The Prass standard monopolar stimulator had the lowest mean threshold at 0.40 mA, with the dissecting instrument having the highest threshold at 0.89 mA for dissected nerve. Pooled mean threshold and saturation increased from 0.6 mA to 1.7 mA (P < .0001) and 1.57 mA to 4.15 mA (P < .001) with fascia covering nerve, respectively. The mean depolarization rate was 100% for monopolar and bipolar electrodes and 81% for dissecting instrument at 1 mA. Only 9% of monopolar electrodes generated an EMG response when stimulated from 2 mm away. Monopolar stimulators are more sensitive for neural mapping, whereas bipolar instruments are more specific, thus reducing false positive stimulation. Dissecting instruments share many features of monopolar stimulators while being more specific, and thus are a viable alternative. 2b Laryngoscope, 2020.

Path Following Based on Waypoints and Real-Time Obstacle Avoidance Control of an Autonomous Underwater Vehicle.

This paper studies three-dimensional (3D) straight line path following and obstacle avoidance control for an underactuated autonomous underwater vehicle (AUV) without lateral and vertical driving forces. Firstly, the expected angular velocities are designed by using two different methods in the kinematic controller. The first one is a traditional method based on Line-of-sight (LOS) guidance law, and the second one is an improved method based on model predictive control (MPC). At the same time, a penalty item is designed by using the obstacle information detected by onboard sensors, which can realize the real-time obstacle avoidance of the unknown obstacle. Then, in order to overcome the uncertainty of the dynamics model and the saturation of actual control input, the dynamic controller is designed by using sliding mode control (SMC) technology. Finally, in the simulation experiment, the performance of the improved control method is verified by comparison with two traditional control methods based on LOS guidance law. Since the constraint of an AUV’s angular velocities are considered in MPC, simulation results show that the improved control method uses MPC, and SMC not only improves the tracking quality of the AUV when switching paths near the waypoints and realizes real-time obstacle avoidance but also effectively reduces the mean square error (MSE) and saturation rate of the rudder angle. Therefore, this control method is more conducive to the system stability and saves energy.

ESTIMASI KANDUNGAN SERPIH (Vsh), POROSITAS EFEKTIF (∅e) DAN SATURASI AIR (Sw) UNTUK MENGHITUNG CADANGAN HIDROKARBON PADA RESERVOAR LIMESTONE LAPANGAN “PRB” DI SUMATERA SELATAN MENGGUNAKAN DATA LOG DAN PETROFISIKA

Log and petrophysics data of research area are that located in South Sumatera Basin, exactly at formation Baturaja will be used for counting the hydrocarbon stock in research field. There are 3 the well datas prosessed to determine the prospect layer of hydrocarbon and estimate the hydrocarbon stock in the productive zone by using 1 petrophysic data from well PRB-3. In order to determine the productive zone of hydrocarbon, the first thing to do is to determine the petrophysics parameters. Parameters used is shale content, effective porosity and water saturation. The value of shale content on “PRB” field shows that reservoir is clean from shale minerals. But, based on the saturation of water, type hydrocarbon in reservoir it is natural gas. Based value of three parameters last, the field “PRB” having 6 zone productive hydrocarbon in each ecploratory wells. Then, determine zone net pay that had been determined by using the cut-off of shale content which is 8% it means hydrocarbon will be produced if the value of shale content under 8%, effective porosity is 5% it means hydrocarbon will be produced if the value of porosity of effective larger than 5% and water saturation is 70% it means that the value of water saturation on field “PRB” must be less than 70% that hydrocarbon can be produced. Average thickness of the net pay in well PRB-1 is 6.78 meter. In well PRB-2, the average thickness is 7.37 meter while in well PRB-3 it is 3,825 meter. The average thickness from those three wells is 3,005 meter. The mean effective porosity of those 3 wells is 8,1% and the mean water saturation is 27,2%. Gas volume formation factor (Bg) is 0,0226 bbl/SCF which the area width is 28 km2. Natural gas stock (OGIP) in this research area is 7,764 BSCF.

Gas hydrate quantification at a pockmark offshore Norway from joint effective medium modelling of resistivity and seismic velocity

Methane emissions from gas hydrate deposits along continental margins may alter the biogeophysical properties of marine environments, both on local and regional scales. The saturation of a gas hydrate deposit is commonly calculated using the elastic or electrical properties measured remotely or in-situ at the site of interest. Here, we used a combination of controlled-source electromagnetic (CSEM), seismic and sediment core data obtained in the Nyegga region, offshore Norway, in a joint elastic-electrical approach to quantify marine gas hydrates found within the CNE03 pockmark. Multiscale analysis of two sediment cores reveals significant differences between the CNE03 pockmark and a reference site located approximately 150 m northwest of CNE03. Gas hydrates and chemosynthetic bivalves were observed in the CNE03 sediments collected. The seismic velocity and electrical resistivity measured in the CNE03 sediment core are consistent with the P-wave velocity (VP) and resistivity values derived from seismic and CSEM remote sensing datasets, respectively. The VP gradually increases (~1.75–1.9 km/s) with depth within the CNE03 pipe-like structure, whereas the resistivity anomaly remains ~3 Ωm. A joint interpretation of the collocated seismic and CSEM data using a joint elastic-electrical effective medium model suggests that for the porosity range 0.55–0.65, the gas hydrate saturation within the CNE03 hydrate stability zone varies with depth between ~20 and 48%. At 0.6 porosity, the hydrate saturation within CNE03 varies between ~23 and 37%, whereas the weighted mean saturation is ~30%. Our results demonstrate that a well-constrained gas hydrate quantification can be accomplished by coupling P-wave velocity and CSEM resistivity data through joint elastic-electrical effective medium modelling. The approach applied in this study can be used as a framework to quantify hydrate in various marine sediments.

Outcome of the Glenn procedure as definitive palliation in single ventricle patients

ObjectivesIn selected single ventricle patients, a Glenn procedure (SV-Glenn) may be considered as definitive palliation. Either the patient is unsuited to progress to a Fontan circulation or a SV-Glenn circulation is preferred. This study aimed at describing the clinical course, and long-term mortality/morbidity of SV-Glenn patients. MethodsAll SV-Glenn patients followed at the University Hospitals Leuven before May 2018 were included. Patients who underwent, or were awaiting, TCPC completion and those who underwent a Glenn in the setting of a biventricular circulation one-and-a-half repair (OAHR), were excluded. ResultsOf 65 Glenn-only patients identified, 21 (32%) had OAHR, whereas 44 (68%) were SV-Glenn patients. Of SV-Glenn patients, 19 died within 6 months after the Glenn procedure. Of 25 SV-Glenn survivors, median age at Glenn was 6.3 (IQR 1.2–29.7) years. Eight were unsuited for TCPC completion; in 17 SV-Glenn was preferred over TCPC completion. Over a median follow-up time of 11 (IQR 3–18) years after the Glenn procedure, 5 (20%) patients died. At latest follow-up 10 (40%) had heart failure, 5 (20%) had atrial and 4 (16%) ventricular arrhythmias, 2 (8%) a thromboembolic event, 7 (28%) required pacemaker implantation, and 2 (8%) had infective endocarditis but none developed cirrhosis or protein-losing enteropathy. Mean saturation at latest follow-up was 87 ± 7%. ConclusionSV-Glenn patients represent a unique and heterogeneous patient population. Outcome was reasonable, although comorbidities, such as heart failure and arrhythmias were not uncommon. In SV-Glenn patients, ‘classic’ complications related to Fontan physiology, such as cirrhosis and protein-losing enteropathy, were absent.

Using continuous overnight pulse oximetry to guide home oxygen therapy in chronic neonatal lung disease

The aims of this study are: (i) to survey the knowledge of paediatric clinicians using overnight continuous pulse oximetry data to guide management of infants with chronic neonatal lung disease (CNLD); (ii) to assess the ability of paediatric clinicians to interpret overnight continuous pulse oximetry data; and (iii) to describe the overnight oximetry interpretation practices of paediatric respiratory specialists. Paediatric clinicians from three tertiary teaching hospitals completed an anonymous survey regarding overnight continuous pulse oximetry in chronic neonatal lung disease. Using a modified Delphi technique, paediatric respiratory specialists participated in a concordance exercise and discussions to establish consensus interpretations for 25 oximetry studies. Paediatric clinicians were invited to complete the same exercise as a comparison. Self-rated knowledge from 74 surveyed clinicians was proportional to clinical experience. Twenty paediatric clinicians and nine paediatric respiratory specialists completed the oximetry exercise with scores of 64% (κ = 0.25) and 80% (κ = 0.45), respectively. Individual parameters like a mean peripheral arterial haemoglobin saturation (SpO2 ) below 93% and percentage time spent below SpO2 93% correlated poorly with the consensus interpretations. Paediatric respiratory specialists instead relied on visual analysis of SpO2 waveforms, utilising the frequency and depth of desaturations to guide management. Interpretation of overnight oximetry data is variable amongst both paediatric clinicians and respiratory specialists. This likely reflects inadequate evidence defining clinically significant intermittent hypoxaemia, whether in terms of desaturation duration, frequency or nadir.

Heat transfer, void fraction and pressure drop during condensation inside inclined smooth and microfin tubes

This paper presents experimental heat transfer and pressure drop measurements during the condensation of R134a at a mean saturation temperature of 40 °C inside a microfinned copper tube with an inner diameter of 8.92 mm and a helix angle of 14°. Experiments were conducted for mean qualities from 0.1 to 0.9 at different inclination angles ranging from −90° (vertically downwards) to +90° (vertically upwards), at mass fluxes of 200–600 kg/m2s. Heat transfer coefficients were calculated directly from measured data, while the frictional pressure drops were obtained from the experimental data using the Bhagwat and Ghajar void fraction correlation developed in 2014. Results were compared with those obtained from a similarly sized smooth tube having an inner diameter of 8.38 mm to obtain the relative microfin heat transfer enhancement and pressure penalty factors. For both tubes, it was found that the heat transfer coefficient increased significantly with the mean vapour quality and mass flux. For the microfin tube, the highest heat transfer coefficients were obtained at tube inclinations of between −15° and −5° (downward flows), while for the smooth tube, the highest heat transfer coefficients occurred between inclinations of between −30° and −15° (downward flows). The heat transfer enhancement factor for the microfin tube was between 0.98 and 2.38 depending on the inclination angle. For both tubes, it was found that higher frictional pressure drops occurred at higher mass fluxes. In most cases, higher vapour qualities produced higher frictional pressure drops depending on the flow pattern. The lowest frictional pressure drop occurred at either horizontal tube positions or vertical downward flow inclinations. Microfin pressure drop penalty factors ranged between approximately 0.8 and 4 depending on the mass flux, inclination and vapour quality.

Pediatric polygraphy: A 6-year experience

The early diagnosis of Sleep Disordered Breathing (SDB) may allow proper intervention. Currently, polygraphy (PG) is a reliable and accessible alternative. To describe and analyze the PG of children > 1 year old with suspicion of SDB. PG of children > 1 year old and adolescents from Concepcion, Chile, with suspected SDB were included, from December 2011 to Au gust 2017. Demographic, clinical and polygraphic variables were collected. It was used descriptive sta tistics, expressing results in median and range. The association between apnea-hypopnea index (AHI) and oxygen saturation was determined by Spearman's Rho, considering significance of p < 0.05. Re sults: 190 studies were analyzed. Age 7.9 years old (1.0-20.6), 61% males. neuromuscular disease (NMD) (24.2%), chronic lung damage (21.1%), upper airway obstruction (UAO) (19.5%), neurological damage (11%), Down syndrome (8.9%), upper airway malformations (7.4%), central hypoventilation (3.7%), obesity (2.6%), and others (1.6%). 55.3% were altered PG, with 53.3% of mild Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS), 30.5% moderate, and 16.2% severe. There were no significant differences in AHI between groups of pathologies (p = 0.032), highlighting a higher AHI in obese patients 9 (0.41-51), and those with NMD 23.9 (0.4-36.6). It was found asso ciation between AHI and oxygen saturation parameters: mean saturation (rho = -0.425; p = 0.001), minimum (rho = -0.654; p = 0.001), and oxygen saturation below 90% (rho = 0.323; p = 0.001) in the whole sample. There was a high percentage of OSAHS in at-risk pediatric patients, especially in those with NMD and obesity. PG is an accessible and implementable tool in a public hospital, a situation that can potentially be extrapolated to other healthcare centers.

Flow boiling of environmentally friendly refrigerants inside a compact enhanced tube

R1233zd(E) has been proposed as low GWP alternative to R245fa. This paper compares the R1233zd(E) and R245fa performance during flow boiling inside a small diameter microfin tube having internal diameter at the fin tip equal to 4.2 mm, 40 fins, 0.15 mm high, and a helix angle of 18°. The experimental measurements were carried out at a constant mean saturation temperature of 30 °C, by varying the refrigerant mass velocity between 100 kg m−2 s−1 and 300 kg m−2 s−1, the mean vapor quality from 0.1 to 0.95, and the heat flux from 15 to 90 kW m−2. The experimental results showed that R1233zd(E) presented almost similar flow boiling heat transfer coefficients at all the investigated mass velocities but slightly higher two-phase frictional pressure drops. The experimental measurements were compared against the calculated values of boiling heat transfer coefficients and frictional pressure drops from several models selected from the open literature.

The estimation of excessive daytime sleepiness in post-stroke patients - a polysomnographic study

Excessive daytime sleepiness (EDS) has been reported in stroke patients. EDS in acute stroke was studied repeatedly, but there is a modest amount of data in post-stroke patients. The aim of this study was to assess the frequency of EDS and characterize sleep architecture in patients >3 months after stroke and identify factors which may affect EDS.66 patients were enrolled, of which 33 had experienced stroke. All underwent a standardized overnight, diagnostic single night polysomnography, including electrocephalogram (EEG) leads, electrooculograms (EOG), chin electromyogram (EMG), and electrocardiogram (ECG). Epworth Sleepiness Scale (ESS) was used to measure subjects’ level of daytime sleepiness.We observed similar total ESS score, total sleep time (TST), sleep efficiency, as well as respiratory disturbance index /apnea-hypopnea index (RDI/AHI), oxygen desaturation index (ODI) and mean heart rate in both groups. We observed positive linear correlation between EDS and mean heart rate in the stroke group (r = 0.46, p < 0.05) as well as between EDS and REM duration (r = 0.23, p < 0.05). In the non-stroke group EDS didn’t correlate with the heart rate or with the REM duration. In the non-stroke group EDS correlated positively with RDI/AHI and ODI index (r = 0.46; p = <0.05 r = 0.41, p < 0.05 and maximal desaturation (r = 0.55, p < 0.05), this correlation was not observed in post-stroke group. In the both groups we observed negative linear correlation between BMI and saturation (stroke group - mean as well as minimal saturation (r = −0.458, p < 0.05; r = −0.578, p < 0.05), non stroke group - minimal but not mean saturation rate (r = −0.544, p < 0.05). We also noticed in both groups positive correlation between BMI and both AHI and ODI index (stroke group respectively: r = 0.430, p < 0.05; r = 0.451, p < 0.05; non-stroke group - BMI and ODI: r = 0.405, p < 0.05). The positive BMI correlation with RDI/AHI was not significant in the non-stroke group. We noticed that BMI correlates with non-REM sleep N1 (r = 0.760, p < 0.05) in post-stroke group, while it correlates negatively with REM sleep (r = -0.709, p < 0.05). There was no such correlation in the non-stroke group.In summary, in stroke patients subjective daytime sleepiness is associated with heart rate, but not with the severity of OSA. Thus ESS (Epworth Scale Score) may be not as useful as a marker of obstructive sleep apnea (OSA) presence or severity in post stroke patient as in the general population.

Cardiovascular Parameters in a Swine Model of Normobaric Hypoxia Treated With 5-Hydroxymethyl-2-Furfural (5-HMF).

Introduction:The consequences of low partial pressure of O2 include low arterial O2 saturations (SaO2), low blood O2 content (CaO2), elevated mean pulmonary artery pressure (PAP), and decreased O2 consumption VO2. 5-hydroxymethyl-2-furfural (5-HMF) binds to the N-terminal valine of hemoglobin (HgB) and increases its affinity to O2. We used an instrumented, sedated swine model to study the effect of 5-HMF on cardiovascular parameters during exposure to acute normobaric hypoxia (NH).MethodsTwenty-three sedated and instrumented swine were randomly assigned to one of three treatment groups and received equal volume of normal saline (VEH), 20 mg/kg 5-HMF (5-HMF-20) or 40 mg/kg 5-HMF (5-HMF-40). Animals then breathed 10% FiO2 for 120 min. Parameters recorded were Cardiac Output (CO), Mean Arterial Blood Pressure (MAP), Heart Rate (HR), Mean Pulmonary Artery Pressure (PAP), SaO2 and saturation of mixed venous blood (SvO2). The P50 was measured at fixed time intervals prior to and during NH.Results5-HMF decreased P50. In the first 30 min of NH, treatment with 5-HMF-20 and 5-HMF-40 resulted in a (1) significantly smaller decrement in SaO2 and SvO2, (2) significantly lower HR and CO, and (3) smaller increase in PAP compared to VEH. In the 120 min of NH there was a trend toward improved mortality with 5-HMF treatment.Conclusion5-HMF treatment decreased P50, improved SaO2, and mitigated increases in PAP in this swine model of NH.

Mito-TEMPO, a mitochondria-targeted antioxidant, prevents N-nitrosodiethylamine-induced hepatocarcinogenesis in mice

BackgroundOxidative stress and mitochondrial dysfunction play a significant role in hepatocarcinogenesis. Mitochondria are source organelle as well as target for free radicals. The oxidative damage to mitochondria can be prevented by mitochondria-targeted antioxidant, mito-TEMPO. However, its efficacy in prevention of hepatocellular carcinoma has not been investigated so far. MethodsMurine model of hepatocarcinogenesis was developed by intraperitoneal administration of N-nitrosodiethylamine to male BALB/c mice. Mito-TEMPO was administered intraperitoneally at weekly intervals, till the completion of the study. The tumours were histopathologically analysed and anti-cancer efficacy of mito-TEMPO was evaluated in terms of survival index, tumour incidence, tumour multiplicity and tumour dielectric parameters. The antioxidant defence status and molecular composition of tumours were assessed. Gap junctions and gap-junctional intercellular communication (GJIC) were studied using ELISA, IHC and Lucifer yellow assay. ResultsMito-TEMPO treatment increased survival of animals by 30%, decreased tumour incidence (25%) and tumour multiplicity (39%). The dielectric parameters of tumours in Mito-TEMPO group were indicative of retarded carcinogenesis. Mito-TEMPO administration normalized mean saturation levels in phospholipids and improved glycogen content of the hepatic tissue. Gap junctions and GJIC which were severely impaired in hepatocarcinogenesis, improved after mito-TEMPO treatment. ConclusionMito-TEMPO was effective in combating hepatocarcinogenesis.

Pressure drop during condensation at low mass fluxes in smooth horizontal and inclined tubes

There are limited studies on pressure drops at low mass fluxes in smooth horizontal and inclined tubes. Thus, this paper presents the pressure drops during the condensation of R134a at low mass fluxes in smooth horizontal and inclined tubes with an internal diameter of 8.38 mm. Experiments were conducted at a saturation temperature of 40 °C at mass fluxes of 50, 75 and 100 kg/m2 s, and mean vapour qualities between 0.1 and 0.9. The temperature differences (between the mean saturation temperature and mean wall temperature) tested were 1, 3, 5, 8, and 10 °C. The pressure drops between the test section inlet and outlet over a length of 1.71 m were measured and were found to be temperature difference dependent. The flow patterns were captured concurrently with two high-speed video cameras positioned at the entrance and exit of the test section through sight glasses. The effect of the vapour quality, temperature difference, mass flux, and inclination angle on the measured and frictional pressure drop was analysed and discussed. It was found that the pressure drops increased with an increase in mass flux, temperature difference and vapour quality. Furthermore, the lowest and highest measured pressure drops were obtained during the downward and upward flows respectively. On the other hand, the opposite was found for the frictional pressure drops.

Concentration, Flux, and Emission Factor of N2O in Rivers with Different Nitrogen Pollution Features

In this study, 22 rivers in Tieling City were selected to study the concentration, flux, and emission factor (EF5r) of N2O. Based on the concentrations and components of nitrogen (N), the 22 rivers can be divided into ammonia nitrogen (NH4+)-polluted rivers (mean NH4+=5.86 mg·L-1), nitrate nitrogen (NO3-)-polluted rivers (mean NO3-=3.05 mg·L-1), and N-limited rivers[mean DIN (NH4++ NO3-)=1.04 mg·L-1]. Overall, the concentration of N2O ranges from 17.03 to 9028.60 nmol·L-1, with a mean value of 546.75 nmol·L-1 (mean saturation=6256%). The emission fluxes across the water-air interface range from 17.21 to 15655.3 μg·(m2·h)-1, with a mean value of 949.36 μg·(m2·h)-1, indicating that those rivers are net sources of atmospheric N2O. The concentration and flux of N2O observed in NH4+-polluted rivers are significantly higher than that in the NO3--polluted and N-limited rivers. According to the method proposed by the IPCC, EF5r varies greatly among the three types of rivers and the coefficient of variation of EF5r is 445%. The EF5r for NO3--polluted rivers is on average 0.0005, which is lower than the recommended value of 0.0025. However, the EF5r for NH4+-polluted rivers is on average 0.4456, which is 180 times the recommended value and may be caused by the lower NO3- concentration of those rivers. The EF5r of N-limited rivers averages 0.0050 and is two times the recommended value. Thus, it is necessary to assess the pollution status of N before calculating the EF5r for the riverine system. We suggest that the EF5r for NH4+-polluted and N-limited rivers should be calculated using[N2O]/[NH4+] and[N2O]/[DIN], respectively, without assessing the composition and concentration of N.

Antagonistic Effect of Flumazenil on Isoflurane in the Emersion of General Anesthesia

Introduction and Objectives: Isoflurane, an inhalational general anesthetic widely used in medical practice, belonging to the group of volatile liquids together with desflurane and sevoflurane. Volatile inhalational anesthetics (halogenated) as mechanism of action, has the property of increasing inhibitory synaptic transmission at postsynaptic level by potentiating ion channels regulated by ligand activated by alpha-amino butyric acid (GABA). Flumazenil is a benzodiazepine. It is currently known that there is no specific drug capable of antagonizing the effects of halogenates that allow the rapid and complete recovery of general anesthesia, for this reason this work focuses its efforts on demonstrating whether flumazenil has the ability to reverse the actions of the patient. Isoflurane and allow an early restoration of the level of consciousness. Materials and Methods: The study to be performed is a clinical type of longitudinal, prospective, unicentric and double blind. The sample will be formed by patients who are going to be subjected to a balanced general anesthesia. The sample will be divided into 2 large groups: group C (control) and group F (Flumazenil). At the end of the surgery, the mixture will be administered according to the selected group in a random manner (Flumazenil 0.25mg or 0.9% solution in a 20cc syringe) and the time of extubation, recovery time of the level of consciousness, time of discharge UCPA and hemodynamic state (FC, TAM and SO2). Results: The flumazenil group showed a significantly shorter time from injection to extubation than the placebo group (p = 0.007). Differences in terms of shorter times needed to achieve Aldrete of 9 points in the flumazenil group (P = 0.04) were observed as were shorter anesthetic arousal times represented by a Ramsey 2. Heart rate, mean arterial pressure and saturation they had similar values between the 2 groups. Conclusion: The study showed that a single dose of 0.25 mg of flumazenil administered at the end of the surgical act, just after completing all surgical stimulation was beneficial (P = 0.007) in the context of extubation times and shorter anesthetic arousal times.

Tigecycline in critically ill patients on continuous renal replacement therapy: a population pharmacokinetic study

BackgroundTigecycline is a vital antibiotic treatment option for infections caused by multiresistant bacteria in the intensive care unit (ICU). Acute kidney injury (AKI) is a common complication in the ICU requiring continuous renal replacement therapy (CRRT), but pharmacokinetic data for tigecycline in patients receiving CRRT are lacking.MethodsEleven patients mainly with intra-abdominal infections receiving either continuous veno-venous hemodialysis (CVVHD, n = 8) or hemodiafiltration (CVVHDF, n = 3) were enrolled, and plasma as well as effluent samples were collected according to a rich sampling schedule. Total and free tigecycline was determined by ultrafiltration and high-performance liquid chromatography (HPLC)-UV. Population pharmacokinetic modeling using NONMEM® 7.4 was used to determine the pharmacokinetic parameters as well as the clearance of CVVHD and CVVHDF. Pharmacokinetic/pharmacodynamic target attainment analyses were performed to explore the potential need for dose adjustments of tigecycline in CRRT.ResultsA two-compartment population pharmacokinetic (PK) model was suitable to simultaneously describe the plasma PK and effluent measurements of tigecycline. Tigecycline dialysability was high, as indicated by the high mean saturation coefficients of 0.79 and 0.90 for CVVHD and CVVHDF, respectively, and in range of the concentration-dependent unbound fraction of tigecycline (45–94%). However, the contribution of CRRT to tigecycline clearance (CL) was only moderate (CLCVVHD: 1.69 L/h, CLCVVHDF: 2.71 L/h) in comparison with CLbody (physiological part of the total clearance) of 18.3 L/h. Bilirubin was identified as a covariate on CLbody in our collective, reducing the observed interindividual variability on CLbody from 58.6% to 43.6%. The probability of target attainment under CRRT for abdominal infections was ≥ 0.88 for minimal inhibitory concentration (MIC) values ≤ 0.5 mg/L and similar to patients without AKI.ConclusionsDespite high dialysability, dialysis clearance displayed only a minor contribution to tigecycline elimination, being in the range of renal elimination in patients without AKI. No dose adjustment of tigecycline seems necessary in CRRT.Trial registrationEudraCT, 2012–005617-39. Registered on 7 August 2013.

Is NREM-predominant obstructive sleep apnea syndrome a different clinical entity?

Background/aim: This study aimed to evaluate whether NREM-predominant obstructive sleep apnea syndrome (OSAS) patients (NREM AHI < REM AHI) have distinct clinical and polysomnographic features compared to REM-predominant OSAS patients (REM AHI > NREM AHI). Materials and methods: A total of 342 patients (93 females and 249 males) who were admitted to the Sleep Disorders Unit at the Gazi University Faculty of Medicine and underwent polysomnography between January 2011 and April 2016 were retrospectively reviewed. Patient data, symptoms related to OSAS, Epworth Sleepiness Scale (ESS) scores, and polysomnographic findings were recorded. The patients were divided into two groups according to the apnea-hypopnea index (AHI) as patients with NREM-predominant OSAS and patients with REM-predominant OSAS. Results: The total AHI in the NREM-predominant group was significantly higher than in the REM-predominant group (P < 0.001). The patients with severe OSAS constituted the majority in both groups, and the rate of patients with severe OSAS was significantly higher in the NREM-predominant group than in the REM-predominant group (P < 0.001). Arousal index and sleep time spent under 90% SaO2 was higher in the NREM-predominant group (P = 0.005, P = 0.001), whereas nocturnal mean and minimum O2 saturation values were lower in the NREM-predominant group compared to patients with REM-predominant OSAS (P < 0.001, P = 0.013). In evaluating systemic disorders, the prevalence of coronary artery disease was significantly higher in the NREM-predominant OSAS group (P < 0.001). Conclusion: Our results showed that patients with NREM-predominant OSAS had a more severe course than patients with REMpredominant OSAS. However, we found no significant difference in sleep-specific symptoms, suggesting that the two groups represented distinct entities.

Ferritin and serum iron as surrogate markers of poor glycemic control and microvascular complications in type 2 diabetes mellitus

This study was designed to find the correlation of iron indices with HbA1c levels and microvascular complications among patients with type 2 DM. Results were consistent with our hypothesis that high iron indices (serum iron and serum ferritin) not high enough to cause hemochromatosis but were still associated with poor glycemic control and its complications. The mean age of study group was 58.57 ± 3.17 years; whereas, the mean age of control group was 53.95 ± 4.43. The mean HbA1c of study group was 9.46 ± 1.31; whereas, the mean HbA1c of control group was 6.42 ± 0.28. The duration of diabetes in study group was 9.69 ± 2.69 years; whereas, it is 5.26 ± 2.81 years in control group. The mean serum iron level in study group was 155.08 ± 22.13 μg/dl; whereas, it is 88.81 ± 38.04 μg/dl in control group. The mean serum ferritin level in study group was 284.79 ± 50.06 ng/ml; whereas, it is 181.31 ± 54.08 ng/ml in control group. The mean serum transferrin saturation in study group was 30.25 ± 9.94; whereas, it is 28.92 ± 6.03 in control group. Out of the 100 patients in the study group, 40 patients had nephropathy, 33 patients had retinopathy, and 31 patients had neuropathy. In 100 patients in the control group, 12 patients had nephropathy, 11 patients had retinopathy, and 12 patients had neuropathy. On applying Pearson’s coefficient of correlation, a moderately significant correlation was obtained between serum iron, ferritin, and HbA1c in study group. However, no significant correlation was obtained with transferrin saturation. On applying regression analysis among HbA1c, serum ferritin, and serum iron, it was observed (the sum of squares of the group was 30.5) that variation is not due to chance.

Solid Form of Lipid-Based Self-Nanoemulsifying Drug Delivery Systems for Minimization of Diacerein Adverse Effects: Development and Bioequivalence Evaluation in Albino Rabbits.

This work aimed to enhance the oral bioavailability of diacerein. The drug was incorporated in self-nanoemulsifying drug delivery system. Ternary phase diagrams were constructed using Capryol™90, Miglyol®812 and isopropyl myristate as oils, Tween®80 and Tween®20 as surfactants and PEG 200 and PEG 300 as co-surfactants. Among a total of 432 formulae, 17 formulae were clear. They were assessed for mean droplet size, polydispersity index (PDI), saturation solubility and transmission electron microscopy. Solid granules were obtained by adsorption on Aeroperl®300. Results for DSC, PXRD, and SEM of prepared granules revealed that diacerein was molecularly dispersed within the formula. Desirability factor was adopted to find the granules with maximum solubility, maximum dissolution efficiency, maximum dissolution rate and percentage of drug dissolved at 5min and minimum dissolution time and Carr's index. The optimized formula consisted of 10% Miglyol®812, 70% Tween®80 and 20% PEG 200 adsorbed to Aeroperl® 300 with a ratio of 2:1 preconcentrate:carrier. It recorded a 3.77-fold increase in bioavailability, compared to the marketed product. Such enhancement means lower doses and less gastrointestinal side effects.