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Background: The plethysmography variability index (PVI) is a non-invasive, real-time, and automated parameter for evaluating fluid responsiveness, but it does not reliably predict fluid responsiveness during low tidal volume (VT) ventilation. We hypothesized that in a 'tidal volume challenge' with a transient increase in tidal volume from 6 to 8 ml Kg− 1, the changes in PVI could predict fluid responsiveness reliably. Method: We performed a prospective interventional study in adult patients undergoing hepatobiliary or pancreatic tumor resections and receiving controlled low VT ventilation. The values for PVI, perfusion index, stroke volume variation, and stroke volume index (SVI) were recorded at baseline VT of 6 ml Kg− 1, 1 min after the VT challenge (8 ml Kg− 1), 1 min after VT 6 ml Kg− 1 reduced back again, and then 5 min after crystalloid fluid bolus 6 ml kg− 1 (actual body weight) administered over 10 min. The fluid responders were identified by SVI rise ≥ 10% after the fluid bolus. Results: The area under the receiver operating characteristic curve for PVI value change (ΔPVI6–8) after increasing VT from 6 to 8 ml Kg− 1 was 0.86 (95% confidence interval, 0.76–0.96), P < 0.001, 95% sensitivity, 68% specificity, and with best cut-off value of absolute change (ΔPVI6–8) = 2.5%. Conclusion: In hepatobiliary and pancreatic surgeries, tidal volume challenge improves the reliability of PVI for predicting fluid responsiveness and changes in PVI values obtained after tidal volume challenge are comparable to the changes in SVI. [ABSTRACT FROM AUTHOR]

Bifunctional N-donor carboxylate linkers generally afford dia and sql topology coordination networks of general formula ML2 that are based upon the MN2(CO2)2 molecular building block (MBB). Herein, we report on a new N-donor carboxylate linker, β-(3,4-pyridinedicarboximido)propionate (PyImPr), which afforded Cd(PyImPr)2via reaction of PyImPrH with Cd(acetate)2·2H2O. We observed that, depending upon whether Cd(PyImPr)2 was prepared by layering or solvothermal methods, 2D or 3D supramolecular isomers, respectively, of Cd(PyImPr)2 were isolated. Single crystal X-ray diffraction studies revealed that both supramolecular isomers are comprised of the same carboxylate bridged rod building block, RBB. We were interested to determine if the ethylene moiety of PyImPr could enable structural flexibility. Indeed, open-to-closed structural transformations occurred upon solvent removal for both phases, but they were found to be irreversible. A survey of the Cambridge Structural Database (CSD) was conducted to analyse the relative frequency of RBB topologies in related ML2 coordination networks in order to provide insight from a crystal engineering perspective. [ABSTRACT FROM AUTHOR]

Germline biallelic pathogenic variants (PVs) in NTHL1 have since 2015 been associated with the autosomal recessive tumor predisposition syndrome: NTHL1 tumor syndrome or NTHL1-associated polyposis. In this systematic review, we aim to systematically investigate the phenotypic and genotypic spectrum of the condition including occurrence of both benign and malignant tumors. The databases PubMed, EMBASE, and Scopus were searched. The search was conducted the 25th of august 2021. We included patients with germline PVs, both heterozygous and homo-/compound heterozygous carriers. Twenty-one papers were selected including 47 patients with biallelic PVs in NTHL1 in 32 families. Twenty-three out of 47 patients (49%) were diagnosed with colorectal cancer (CRC) (mean age: 55, range: 31–73) and 12 out of 22 female patients (55%) were diagnosed with breast cancer (mean age: 49, range: 36–63). Apart from three, all patients who underwent a colonoscopy, had colonic adenomas (93%), and three patients (6%) had duodenal adenomatosis. We also identified 158 heterozygous carriers of germline PVs in NTHL1. Twenty-six out of 68 (38%) heterozygous carriers, who underwent colonoscopy, had colonic polyps or adenomas. Twenty-nine heterozygous carriers (18%) were diagnosed with CRC and 59 (49%) with breast cancer. We observed a high frequency of early onset CRC and breast cancer in patients with NTHL1 tumor syndrome. Subsequently, colorectal, breast, and endometrial cancer screening programs are recommended for NTHL1 biallelic carriers. Trial registry PROSPERO: CRD42021275159. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fabrication of zeolite‐like metal–organic frameworks (ZMOFs) for advanced applications, such as enzyme immobilization, is of great interest but is a great synthetic challenge. Herein, we have developed a new strategy using proteins as structure‐directed agents to direct the formation of new ZMOFs that can act as versatile platforms for the in situ encapsulation of proteins under ambient conditions. Notably, protein incorporation directs the formation of a ZMOF with a sodalite (sod) topology instead of a non‐porous diamondoid (dia) topology under analogous synthetic conditions. Histidines in proteins play a crucial role in the observed templating effect. Modulating histidine content thereby influenced the resultant MOF product (from dia to dia + sod mixture and, ultimately, to sod MOF). Moreover, the resulting ZMOF‐incorporated proteins preserved their activity even after exposure to high temperatures and organic solvents, demonstrating their potential for biocatalysis and biopharmaceutical applications. [ABSTRACT FROM AUTHOR]

Fabrication of zeolite‐like metal–organic frameworks (ZMOFs) for advanced applications, such as enzyme immobilization, is of great interest but is a great synthetic challenge. Herein, we have developed a new strategy using proteins as structure‐directed agents to direct the formation of new ZMOFs that can act as versatile platforms for the in situ encapsulation of proteins under ambient conditions. Notably, protein incorporation directs the formation of a ZMOF with a sodalite (sod) topology instead of a non‐porous diamondoid (dia) topology under analogous synthetic conditions. Histidines in proteins play a crucial role in the observed templating effect. Modulating histidine content thereby influenced the resultant MOF product (from dia to dia + sod mixture and, ultimately, to sod MOF). Moreover, the resulting ZMOF‐incorporated proteins preserved their activity even after exposure to high temperatures and organic solvents, demonstrating their potential for biocatalysis and biopharmaceutical applications. [ABSTRACT FROM AUTHOR]

Developing new materials for the fabrication of proton exchange membranes (PEMs) for fuel cells is of great significance. Herein, a series of highly crystalline, porous, and stable new covalent organic frameworks (COFs) have been developed by a stepwise synthesis strategy. The synthesized COFs exhibit high hydrophilicity and excellent stability in strong acid or base (e.g. 12 m NaOH or HCl) and boiling water. These features make them ideal platforms for proton conduction applications. Upon loading with H3PO4, the COFs (H3PO4@COFs) realize an ultrahigh proton conductivity of 1.13×10−1 S cm−1, the highest among all COF materials, and maintain high proton conductivity across a wide relative humidity (40–100 %) and temperature range (20–80 °C). Furthermore, membrane electrode assemblies were fabricated using H3PO4@COFs as the solid electrolyte membrane for proton exchange resulting in a maximum power density of 81 mW cm−2 and a maximum current density of 456 mA cm−2, which exceeds all previously reported COF materials. [ABSTRACT FROM AUTHOR]

Developing new materials for the fabrication of proton exchange membranes (PEMs) for fuel cells is of great significance. Herein, a series of highly crystalline, porous, and stable new covalent organic frameworks (COFs) have been developed by a stepwise synthesis strategy. The synthesized COFs exhibit high hydrophilicity and excellent stability in strong acid or base (e.g. 12 m NaOH or HCl) and boiling water. These features make them ideal platforms for proton conduction applications. Upon loading with H3PO4, the COFs (H3PO4@COFs) realize an ultrahigh proton conductivity of 1.13×10−1 S cm−1, the highest among all COF materials, and maintain high proton conductivity across a wide relative humidity (40–100 %) and temperature range (20–80 °C). Furthermore, membrane electrode assemblies were fabricated using H3PO4@COFs as the solid electrolyte membrane for proton exchange resulting in a maximum power density of 81 mW cm−2 and a maximum current density of 456 mA cm−2, which exceeds all previously reported COF materials. [ABSTRACT FROM AUTHOR]

Background: Vitamin D levels have been linked to certain pain states, including migraine. This study investigated whether vitamin D supplementation would be beneficial for adult patients with migraine (ClinicalTrials.gov Identifier: NCT01695460).Methods: A randomized, double-blinded, placebo-controlled parallel trial was conducted in migraine patients (36 women and 12 men, 18-65 years of age). A 4-week baseline period was conducted before randomization to 24 weeks of treatment. Participants were assigned to receive D3-Vitamin (n = 24, 18 women and 6 men, 100 μg/day D3-Vitamin) or placebo (n = 24, 18 women and 6 men). Migraine attacks and related symptoms were assessed by self-reported diaries. The response rate (i.e. experiencing a 50% or greater reduction in migraine frequency from baseline to week 24), change in migraine severity, and number of migraine days were recorded. Changes in migraine-related symptoms, HIT-6TM scores, and pain sensitivity tests (pressure pain threshold and temporal summation) were also evaluated. Serum levels of both 25 (OH)D and 1,25 (OH)2D were assessed from baseline to week 24.Results: The number of headache days changed from 6.14 ± 3.60 in the treatment group and 5.72 ± 4.52 in the placebo group at baseline to 3.28 ± 3.24 and 4.93 ± 3.24 by the end of the trial, respectively. Migraine patients on D3-Vitamin demonstrated a significant decrease (p < .001) in migraine frequency from baseline to week 24 compared with placebo. However, migraine severity, pressure pain thresholds, or temporal summation did not show a significant change. 25(OH)D levels increased significantly for the D3-Vitamin group during the first 12 weeks of treatment. There was no significant change in 1,25(OH)2D. No side-effects were reported or noted.Conclusions: D3-Vitamin was superior to placebo in reducing migraine days in migraine patients. Larger studies are required to confirm that vitamin D3 might be one of the prophylactic options for adult patients with migraine. [ABSTRACT FROM AUTHOR]

The increasing interest of medical institutes in the development of imaging services to include the hybrid system [Positron Emission Tomography combined with Computed Tomography (PET/CT)], this system is acquiring explosive growth due to its ability to accurately detect and stage many types of cancer and follow the progress of treatments. An increasing demand for use of (18F-FDG PET) in oncology has been the main reason for its growth. The physical characteristics of positron emissions result in higher radiation risk for staff and growing use of PET/CT for diagnostic purposes increase radiation exposure. The objective of this study was to estimate the radiation exposure to the medical physicists, technicians and nurses working in three Egyptian nuclear medicine institutes under our investigations, based on the whole body collective dose measured by thermoluminescent dosimeters (TLDs) and the effective dose per study received by medical staff were measured by electronic pocked dosimeters and the finger doses by ring dosimeter during a period of six months. The (mean± SD) dose measured per PET/CT procedure were (2.45±0.137, 3.22±0.218 and 1.69±0.11) μSv for the medical physicist, technician and nurse respectively. The (mean± SD) dose measured per MBq of 18F-FDG were (7.35±0.43, 9.73±0.66 and 5.13±0.33) nSv/MBq for the medical physicist, technician and nurse respectively. The (mean± SD) finger dose measured per 18F-FDGPET/CT scans were (179.9±24.94, 8.82±2.912 and 24.15±4.164) μSv for the medical physicist, technician and nurse respectively. [ABSTRACT FROM AUTHOR]

Copyright of Saudi Medical Journal is the property of Saudi Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

INTRODUCTION: Inhaled nitric oxide (iNO) is the standard therapy for infants with persistent pulmonary hypertension of the newborn (PPHN). Recently, sildenafil has been evaluated as an alternative or adjunctive pulmonary vasodilator. OBJECTIVE: To assess the effectiveness of adding sildenafil as an early adjunctive therapy together with iNO when treating newborns with PPHN and/or hypoxemic respiratory failure. METHODS: This is a randomized placebo trial on newborns with gestational age > 34 weeks, postnatal age < 48 hours, and diagnosed with PPHN (oxygen index (OI) ⩾ 20). Newborns were randomized to two groups: Group A-received oral sildenafil and iNO, and group B-received placebo and iNO. Initial and follow up echocardiography were performed over 14 days period. RESULTS: A total of 24 newborns were recruited; 13 of them received sildenafil in addition to iNO and 11 received iNO and placebo. The most common causes of PPHN were meconium aspiration syndrome, pneumonia, and RDS. At the starting point, OI was marginally higher in the intervention group without statistical significance (29 vs 28). There were no differences between the two groups regarding surfactant administration, incidence of pneumothoraces, and the underlying causes of PPHN. Sildenafil or placebo treatment started within 12 hours after starting iNO (8 vs 6 hours). CONCLUSION: Early use of oral sildenafil next to iNO in cases of PPHN was tolerated well by newborns and it did not show significant adverse effects. Further studies with a larger sample size is needed to assess its effecacy. [ABSTRACT FROM AUTHOR]

Biofuel is an alternative fuel source for diesel engines. Nowadays, biofuel attracts more interest due to the depletion of mineral petroleum resources. The aim of this paper is to study the effect of ambient temperature on the combustion and performance of a diesel engine when using ethanol and methanol as fuels. The one-dimensional numerical analysis uses the GT-Power software program to simulate a commercial four-cylinder diesel engine. The diesel engine was simulated in order to study the characteristics of engine combustion when the engine is operating with ethanol and methanol as alternative fuels. The simulations were conducted under the full-load condition for an engine operating with diesel, ethanol, and methanol. Ambient temperatures used for each test were 30, 40, and 50 °C. The results show that the in-cylinder pressure for ethanol is higher than that of methanol and diesel at different ambient temperatures, while methanol was found to yield a higher rate of heat release compared to ethanol and diesel. However, changes in ambient temperature in the inlet pipe do not affect the rate of heat release when using any fuel. It can be concluded that biofuels are excellent fuel alternatives to replace diesel in the future. [ABSTRACT FROM AUTHOR]

Copyright of Al-Azhar Journal of Agricultural Sciences Sector Research is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)