Nanomaterials in electrochemical nanobiosensors of miRNAs.

Nanomaterial-based biosensors have received significant attention owing to their unique properties, especially enhanced sensitivity. Recent advancements in biomedical diagnosis have highlighted the role of microRNAs (miRNAs) as sensitive prognostic and diagnostic biomarkers for various diseases. Current diagnostics methods, however, need further improvements with regards to their sensitivity, mainly due to the low concentration levels of miRNAs in the body. The low limit of detection of nanomaterial-based biosensors has turned them into powerful tools for detecting and quantifying these biomarkers. Herein, we assemble an overview of recent developments in the application of different nanomaterials and nanostructures as miRNA electrochemical biosensing platforms, along with their pros and cons. The techniques are categorized based on the nanomaterial used.

Identification and characterization of inulinases by bioinformatics analysis of bacterial glycoside hydrolases family 32 (GH32).

The glycoside hydrolase family contains enzymes that break the glycosidic bonds of carbohydrates by hydrolysis. Inulinase is one of the most important industrial enzymes in the family of Glycoside Hydrolases 32 (GH32). In this study, to identify and classify bacterial inulinases initially, 16,002 protein sequences belonging to the GH32 family were obtained using various databases. The inulin-effective enzymes (endoinulinase and exoinulinase) were identified. Eight endoinulinases (EC 3.2.1.7) and 4318 exoinulinases (EC 3.2.1.80) were found. Then, the localization of endoinulinase and exoinulinase enzymes in the cell was predicted. Among them, two extracellular endoinulinases and 1232 extracellular exoinulinases were found. The biochemical properties of 363 enzymes of the genus Arthrobacter, Bacillus, and Streptomyces (most abundant) showed that exoinulinases have an acid isoelectric point up to the neutral range due to their amino acid length. That is, the smaller the protein (336 aa), the more acidic the pI (4.39), and the larger the protein (1207 aa), the pI is in the neutral range (8.84). Also, a negative gravitational index indicates the hydrophilicity of exoinulinases. Finally, considering the biochemical properties affecting protein stability and post-translational changes studies, one enzyme for endoinulinase and 40 enzymes with desirable characteristics were selected to identify their enzyme production sources. To screen and isolate enzyme-containing strains, now with the expansion of databases and the development of bioinformatics tools, it is possible to classify, review and analyze a lot of data related to different enzyme-producing strains. Although, in laboratory studies, a maximum of 20 to 30 strains can be examined. Therefore, when more strains are examined, finally, strains with more stable and efficient enzymes were selected and introduced for laboratory activities. The findings of this study can help researchers to select the appropriate gene source from introduced strains for cloning and expression heterologous inulinase, or to extract native inulinase from introduced strains.

Alprazolam Detection Using an Electrochemical Nanobiosensor Based on AuNUs/Fe-Ni@rGO Nanocomposite.

Despite all the psychological advantages of alprazolam, its long list of toxic properties and interactions has caused concern and highlighted the need for a reliable sensing method. In this study, we developed a simple, highly sensitive electrochemical nanobiosensor to determine the desirable dose of alprazolam, averting the undesirable consequences of overdose. Gold nanourchins (AuNUs) and iron-nickel reduced graphene oxide (Fe-Ni@rGO) were immobilized on a glassy carbon electrode, which was treated beforehand. The electrode surface was characterized using cyclic voltammetry, Fourier transform infrared spectroscopy, scanning electron microscopy/energy-dispersive X-ray spectroscopy, and differential pulse voltammetry. The fabricated sensor showed two linear ranges (4 to 500 µg L-1 and 1 to 50 mg L-1), low limit of detection (1 µg L-1), high sensitivity, good repeatability, and good recovery. Increased -OH and carboxyl (-COOH) groups on the electrode surface, resulting in improved the adsorption of alprazolam and thus lower limit of detection. This nanobiosensor could detect alprazolam powder dissolved in diluted blood serum; we also studied other benzodiazepine drugs (clonazepam, oxazepam, and diazepam) with this nanobiosensor, and results were sensible, with a significant difference.

The role of the tumor microenvironment in colorectal cancer and the potential therapeutic approaches.

BACKGROUND: Colorectal cancer (CRC) with a high prevalence is recognized as the fourth most common cause of cancer-related death globally. Over the past decade, there has been growing interest in the network of tumor cells, stromal cells, immune cells, blood vessel cells, and fibroblasts that comprise the tumor microenvironment (TME) to identify new therapeutic interventions. METHODS: Databases, such as Google Scholar, PubMed, and Scopus, were searched to provide an overview of the recent research progress related to targeting the TME as a novel therapeutic approach. RESULTS: Tumor microenvironment as a result of the cross talk between these cells may result in either advantages or disadvantages in tumor development and metastasis, affecting the signals and responses from the surrounding cells. Whilst chemotherapy has led to an improvement in CRC patients' survival, the metastatic aspect of the disease remains difficult to avoid. CONCLUSIONS: The present review emphasizes the structure and function of the TME, alterations in the TME, its role in the incidence and progression of CRC, the effects on tumor development and metastasis, and also the potential of its alterations as therapeutic targets. It should be noted that providing novel studies in this field of research might help us to achieve practical therapeutic strategies based on their interaction.

A novel method for the chaperone aided and efficient production of human proinsulin in the prokaryotic system.

With the rapid spread of diabetes in human society, the demand for insulin and its precursor (proinsulin) continues to rise. Therefore, the introduction of new methods for their production is essential. In the present study, human proinsulin, while ligated to αB-crystallin chaperone, was effectively expressed in the prokaryotic host system and then purified by the ion-exchange chromatography at high purity (>97%). In the next step, human proinsulin with relatively high efficiency was released chemically from the hybrid protein (αB-pIns) and then purified using an appropriate gel filtration column. The SDS-PAGE and HPLC analyses confirmed the high purity, while mass spectroscopy assessment verified the exact molecular mass of the human proinsulin. Using a well-established protocol, the protein was folded in a one-step folding process with a yield of about 70%. The assessment of the secondary structures of the human proinsulin by Raman and FTIR spectroscopy suggested that this protein is rich in α-helix. Also, the conformation of disulfide bonds in the folded proinsulin was confirmed by Raman spectroscopy. The recombinant human proinsulin also demonstrated hypoglycemic activity and mitogenic action (induction of cell proliferation). The method proposed in this work for the production of human proinsulin is easy to run and does not depend on expensive and complex equipment. Thus, it can be used in the industrial production of human proinsulin.

Multifunctional and Self-Healable Intelligent Hydrogels for Cancer Drug Delivery and Promoting Tissue Regeneration In Vivo.

Regenerative medicine seeks to assess how materials fundamentally affect cellular functions to improve retaining, restoring, and revitalizing damaged tissues and cancer therapy. As potential candidates in regenerative medicine, hydrogels have attracted much attention due to mimicking of native cell-extracellular matrix (ECM) in cell biology, tissue engineering, and drug screening over the past two decades. In addition, hydrogels with a high capacity for drug loading and sustained release profile are applicable in drug delivery systems. Recently, self-healing supramolecular hydrogels, as a novel class of biomaterials, are being used in preclinical trials with benefits such as biocompatibility, native tissue mimicry, and injectability via a reversible crosslink. Meanwhile, the localized therapeutics agent delivery is beneficial due to the ability to deliver more doses of therapeutic agents to the targeted site and the ability to overcome post-surgical complications, inflammation, and infections. These highly potential materials can help address the limitations of current drug delivery systems and the high clinical demand for customized drug release systems. To this aim, the current review presents the state-of-the-art progress of multifunctional and self-healable hydrogels for a broad range of applications in cancer therapy, tissue engineering, and regenerative medicine.

The Life Cycle Assessment for Polylactic Acid (PLA) to Make It a Low-Carbon Material.

The massive plastic production worldwide leads to a global concern for the pollution made by the plastic wastes and the environmental issues associated with them. One of the best solutions is replacing the fossil-based plastics with bioplastics. Bioplastics such as polylactic acid (PLA) are biodegradable materials with less greenhouse gas (GHG) emissions. PLA is a biopolymer produced from natural resources with good mechanical and chemical properties, therefore, it is used widely in packaging, agriculture, and biomedical industries. PLA products mostly end up in landfills or composting. In this review paper, the existing life cycle assessments (LCA) for PLA were comprehensively reviewed and classified. According to the LCAs, the energy and materials used in the whole life cycle of PLA were reported. Finally, the GHG emissions of PLA in each stage of its life cycle, including feedstock acquisition and conversion, manufacturing of PLA products, the PLA applications, and the end of life (EoL) options, were described. The most energy-intensive stage in the life cycle of PLA is its conversion. By optimizing the conversion process of PLA, it is possible to make it a low-carbon material with less dependence on energy sources.

A collection of the novel coronavirus (COVID-19) detection assays, issues, and challenges.

The global pandemic of COVID-19 has rapidly increased the number of infected cases as well as asymptomatic individuals in many, if not all the societies around the world. This issue increases the demand for accurate and rapid detection of SARS-CoV-2. While accurate and rapid detection is critical for diagnosing SARS-CoV-2, the appropriate course of treatment must be chosen to help patients and prevent its further spread. Testing platform accuracy with high sensitivity and specificity for SARS-CoV-2 is equally important for clinical, regional, and global arenas to mitigate secondary transmission rounds. The objective of this article is to compare the current detection technology and introduce the most accurate and rapid ones that are suitable for pandemic circumstances. Hence, the importance of rapid detection in societies is discussed initially. Following this, the current technology for rapid detection of SARS-CoV-2 is explained and classified into three different categories: nucleic acid-based, protein-based, and point of care (PoC) detection testing. Then, the current issues for diagnostic procedures in laboratories are discussed. Finally, the role of new technologies in countering COVID-19 is also introduced to assist researchers in the development of accurate and timely detection of coronaviruses. As coronavirus continues to affect human lives in a detrimental manner, the development of rapid and accurate virus detection methods could promote COVID-19 diagnosis accessible to both individuals and the mass population at patient care. In this regard, rRT-PCR and multiplex RT-PCR detection techniques hold promise.

Thermal Degradation Kinetics and Modeling Study of Ultra High Molecular Weight Polyethylene (UHMWP)/Graphene Nanocomposite.

The incorporation of nanofillers such as graphene into polymers has shown significant improvements in mechanical characteristics, thermal stability, and conductivity of resulting polymeric nanocomposites. To this aim, the influence of incorporation of graphene nanosheets into ultra-high molecular weight polyethylene (UHMWPE) on the thermal behavior and degradation kinetics of UHMWPE/graphene nanocomposites was investigated. Scanning electron microscopy (SEM) analysis revealed that graphene nanosheets were uniformly spread throughout the UHMWPE's molecular chains. X-Ray Diffraction (XRD) data posited that the morphology of dispersed graphene sheets in UHMWPE was exfoliated. Non-isothermal differential scanning calorimetry (DSC) studies identified a more pronounced increase in melting temperatures and latent heat of fusions in nanocomposites compared to UHMWPE at lower concentrations of graphene. Thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) revealed that UHMWPE's thermal stability has been improved via incorporating graphene nanosheets. Further, degradation kinetics of neat polymer and nanocomposites have been modeled using equations such as Friedman, Ozawa-Flynn-Wall (OFW), Kissinger, and Augis and Bennett's. The "Model-Fitting Method" showed that the auto-catalytic nth-order mechanism provided a highly consistent and appropriate fit to describe the degradation mechanism of UHMWPE and its graphene nanocomposites. In addition, the calculated activation energy (Ea) of thermal degradation was enhanced by an increase in graphene concentration up to 2.1 wt.%, followed by a decrease in higher graphene content.

The Effect of Poly (Ethylene glycol) Emulation on the Degradation of PLA/Starch Composites.

As a hydrophilic renewable polymer, starch has been widely used in biocompatible plastics as a filler for more than two decades. The present study aimed at investigating the effects of polyethylene glycol (PEG), as a plasticizer, on the physicochemical properties of a hybrid composite-polylactic acid (PLA) and thermoplastic starch (TPS). A solvent evaporation process was adopted to gelatinize the starch and disparate PEG contents ranging from 3 to 15 wt.% (with respect to the sample weight) were examined. It was revealed that the increase in the PEG content was accompanied by an increment in the starch gelatinization degree. Referring to the microstructural analyses, the TPS/PLA mixture yielded a ductile hybrid composite with a fine morphology and a uniform phase. Nevertheless, two different solvents, including acetone and ethanol, were used to assess if they had any effect on the hybrid's morphology, tensile strength and thermal properties. It was found that ethanol culminated in a porous hybrid composite with a finer morphology and better starch distribution in the PLA structure than acetone. As the result of PEG addition to the composite, the crystallinity and tensile strength were decreased, whereas the elongation increased. The hydrolytic degradation of samples was assessed under different pH and thermal conditions. Moreover, the microbial degradation of the PLA/TPS hybrid composite containing different PEG molar fractions was investigated in the soil for 45 days. The rate of degradation in both hydrolytic and biodegradation increased in the samples with a higher amount of PEG with ethanol solvent.

Kinetic Modeling and Degradation Study of Liquid Polysulfide Resin-Clay Nanocomposite.

Kinetic modeling and degradation study of liquid polysulfide (LPS)/clay nanocomposite is possible through Ozawa-Flynn-Wall (OFW) and Kissinger methods. Comparing the results of these models with experimental data leads to provide an accurate degradation kinetic evaluation of these materials. To this aim, the morphology and distribution of clay nanoparticles (CNPs) within the LPS matrix were investigated using Field Emission Scanning Electron Microscopy (FESEM) and X-ray diffraction (XRD). To evaluate the interaction between the LPS and the CNPs, the Fourier transform infrared (FTIR) identification was utilized. Furthermore, to investigate the kinetics of degradation, the thermal gravimetric analysis (TGA) and derivative thermogravimetry (DTG) of the samples were used in the nitrogen atmosphere with the help of Kissinger and Ozawa-Flynn-Wall (OFW) models. The characterization results confirmed the homogenous dispersion of the CNPs into the LPS matrix. In addition, the presence of CNPs increased the thermal stability and activation energy (Ea) of the samples at different conversion rates. Moreover, the OFW method was highly consistent with the experimental data and provided an appropriate fit for the degradation kinetics.

Chinese water managers' long-term climate information needs.

Decision-makers can use climate information to adapt to the risks of climate variability and change. The adequate provision of climate information is critical for adaptation planning in climate-sensitive sectors. However, for climate products to be appropriately tailored for these sectors, it is necessary to identify and understand users' specific information needs. The aim of this research was to assess the use of and need for climate information by water managers in China, with a focus on long-term climate information in the Yellow and Yangtze River basins. Data was collected from regional water managers, and climate information providers using a workshop (n = 15), and semi-structured interviews (n = 27). It was found that water manages in China required climate data with different timescales and variables. The findings show that water managers receive historical, weather and seasonal forecasts data from the China Meteorological Administration (CMA) mainly because there is a close dialogue between data providers and users in terms of historical, weather, and seasonal climate data that does not exist with regard to climate change projections. The use of external sources of climate change projections by users in China allows critical evaluation of climate services provided by the CMA; from that, an understanding of the limitations of current services such as limited variables and timescales was established.

The Flame Retardancy of Polyethylene Composites: From Fundamental Concepts to Nanocomposites.

Polyethylene (PE) is one the most used plastics worldwide for a wide range of applications due to its good mechanical and chemical resistance, low density, cost efficiency, ease of processability, non-reactivity, low toxicity, good electric insulation, and good functionality. However, its high flammability and rapid flame spread pose dangers for certain applications. Therefore, different flame-retardant (FR) additives are incorporated into PE to increase its flame retardancy. In this review article, research papers from the past 10 years on the flame retardancy of PE systems are comprehensively reviewed and classified based on the additive sources. The FR additives are classified in well-known FR families, including phosphorous, melamine, nitrogen, inorganic hydroxides, boron, and silicon. The mechanism of fire retardance in each family is pinpointed. In addition to the efficiency of each FR in increasing the flame retardancy, its impact on the mechanical properties of the PE system is also discussed. Most of the FRs can decrease the heat release rate (HRR) of the PE products and simultaneously maintains the mechanical properties in appropriate ratios. Based on the literature, inorganic hydroxide seems to be used more in PE systems compared to other families. Finally, the role of nanotechnology for more efficient FR-PE systems is discussed and recommendations are given on implementing strategies that could help incorporate flame retardancy in the circular economy model.

Comparative Study of Fentanyl vs Dexmedetomidine as Adjuvants to Intrathecal Bupivacaine in Cesarean Section: A Randomized, Double-Blind Clinical Trial.

PURPOSE: Effective postoperative analgesia is essential in cesarean section. This study aimed to compare postoperative analgesia and hemodynamic changes after intrathecal use of fentanyl or dexmedetomidine combined with bupivacaine. PATIENTS AND METHODS: This study involved 110 pregnant women with ASA I and II and gestational age ≥37 weeks who were candidates for elective cesarean section. They were randomly divided into two groups of 55; Group B-D received 10 mg bupivacaine (0.5%) + 5 µg dexmedetomidine and Group B-F received 10 mg bupivacaine (0.5%) + 25 µg fentanyl, intrathecally. The onset of block, duration of analgesia, the score of pain intensity, hemodynamic changes, Apgar scores, and any adverse events were evaluated. P-value <0.05 was considered statistically significant. RESULTS: Patients in two groups were similar in terms of demographic characteristics and ASA classification. Duration of analgesia in the B-D group was significantly longer than B-F group (428.64±73.39 vs 273.18±61.91 min; P<0.001). The score of pain intensity during recovery time in the B-D group was significantly lower than that of B-F group (0.33±0.84 vs 0.51±0.57 min; P=0.004). The onset of block was also faster in the B-D group than B-F group (98.27±35.95 vs 110.45±37.69 seconds; P=0.036). The two groups did not show significant differences in hemodynamic changes and other variables (P>0.05). CONCLUSION: Compared with fentanyl, it seems that adding 5 µg dexmedetomidine to bupivacaine has a better effect on postoperative pain management in cesarean section under spinal anesthesia.

Improving the adsorption potential of chitosan for heavy metal ions using aromatic ring-rich derivatives.

This study describes the simple preparation process of modified chitosan (CS) that can effectively adsorb lead ion in the aqueous medium. To design this adsorbent with high binding sites, the Schiff base ligand with three aromatic rings, 3,3-diphenylpropylimine methyl benzaldehyde (PPIMB), is synthesized. The PPIMB forms several new binding sites in modified CS by making a new imine bond with free NH2 in CS structure. The structural and physicochemical characteristics of the magnetically modified chitosan (MCS-PPIMB) are evaluated by FTIR, XRD, SEM, EDX, DLS, VSM, and TG techniques. The effect of some factors, such as pH, collision time, adsorbent dosage, and initial concentration of Pb(II), is investigated on the adsorption capacity of the adsorbent. The adsorption capacity of MCS-PPIMB against Pb(II) is obtained 230.48 mg/g. The adsorption behavior of MCS-PPIMB is fitted efficiently by the Langmuir isotherm model. The fluorometric studies show that the adsorbent has a sharp emission peak at 698 nm, and Pb(II) ion can quench the fluorescence emission of MCS-PPIMB at low concentration. The theoretical studies confirm the strong binding energy of the Pb atom with aromatic rings and imine groups of the MCS-PPIMB.

Development of a Highly Proliferated Bilayer Coating on 316L Stainless Steel Implants.

In this research, a bilayer coating has been applied on the surface of 316 L stainless steel (316LSS) to provide highly proliferated metallic implants for bone regeneration. The first layer was prepared using electrophoretic deposition of graphene oxide (GO), while the top layer was coated utilizing electrospinning of poly (ε-caprolactone) (PCL)/gelatin (Ge)/forsterite solutions. The morphology, porosity, wettability, biodegradability, bioactivity, cell attachment and cell viability of the prepared coatings were evaluated. The Field Emission Scanning Electron Microscopy (FESEM) results revealed the formation of uniform, continuous, and bead-free nanofibers. The Energy Dispersive X-ray (EDS) results confirmed well-distributed forsterite nanoparticles in the structure of the top coating. The porosity of the electrospun nanofibers was found to be above 70%. The water contact angle measurements indicated an improvement in the wettability of the coating by increasing the amount of nanoparticles. Furthermore, the electrospun nanofibers containing 1 and 3 wt.% of forsterite nanoparticles showed significant bioactivity after soaking in the simulated body fluid (SBF) solution for 21 days. In addition, to investigate the in vitro analysis, the MG-63 cells were cultured on the PCL/Ge/forsterite and GO-PCL/Ge/forsterite coatings. The results confirmed an excellent cell adhesion along with considerable cell growth and proliferation. It should be also noted that the existence of the forsterite nanoparticles and the GO layer substantially enhanced the cell proliferation of the coatings.

The effect of dexmedetomidine on spinal anesthesia quality and hemodynamic changes in patients undergoing inguinal hernia repair surgery: intravenous versus intrathecal.

PURPOSE: The aim of this study was to evaluate the quality of spinal anesthesia and hemodynamic parameters of intravenous versus intrathecal dexmedetomidine in patients undergoing inguinal hernia repair surgery under spinal anesthesia. METHODS: Fifty male patients aged 18-70 years with ASA I and II were randomly divided into two groups of 25 patients receiving either intravenous (1 µg/kg infused during 10 min before blockade) or intrathecal (5 µg, added to local anesthetics) dexmedetomidine. The duration of analgesia, sensory and motor blockade levels, the score of pain intensity, post-operative analgesic usage and the level of sedation as well as hemodynamic changes, and complications were recorded. RESULTS: The duration of analgesia in the intrathecal group was significantly longer than intravenous group (403.588 ± 93.706 vs. 274.048 ± 47.266 min; P < 0.001). Duration of the sensory and motor blockade were significantly longer in intrathecal than intravenous group (230.440 ± 26.494 vs. 181.400 ± 28.850 min; P < 0.001 for sensory block, and 253.800 ± 32.637 vs. 205.400 ± 30.921 min; P < 0.001 for motor block). The score of pain intensity was lower in the intrathecal group in the post-operative period (3.680 ± 1.680 vs. 5.520 ± 1.901; P = 0.001 and 2.360 ± 1.320 vs. 3.24 ± 1.69; P = 0.041, respectively, for the time 6 and 12). Ramsay sedation score was higher in the intravenous group during surgery but it was higher in intrathecal group during recovery room period (P < 0.05). Moreover, the incidence of bradycardia was significantly lower in the intrathecal group (0% vs. 36% respectively; P = 0.002). CONCLUSION: Administration of intrathecal dexmedetomidine along with local anesthetics can be recommended to increase the quality of spinal anesthesia with minimal complications.

MARK4 protein can explore the active-like conformations in its non-phosphorylated state.

Microtubule affinity-regulating kinase 4 (MARK4) is a Ser/Thr protein kinase, best known for its role in phosphorylating microtubule associated proteins, causing their detachment from microtubules. In the current study, the non-phosphorylated conformation of the activation loop was modeled in a structure representing the enzymatically inactive form of this protein, and its dynamics were evaluated through a 100 ns initial all-atom simulation, which was prolonged by another 2 µs. Although the activation loop was folding on itself and was leaning toward ATP site in the initial modeled structure, soon after the initiating the simulation, this loop stretched away from the ATP binding site and stably settled in its new position for the rest of simulation time. A network of hydrogen bonds, mainly between the activation segment residues, αC-helix and the catalytic loop reinforced this conformation. Interestingly, several features of active kinase conformation such as formation of R-spine, Glu106-Lys88 salt-bridge, and DFG-In motif were observed during a considerable number of trajectory frames. However, they were not sustainably established during the simulation time, except for the DFG-In motif. Consequently, this study introduces a stable conformation of the non-phosphorylated form of MARK4 protein with a partially stretched activation loop conformation as well as partial formation of R-spine, closely resembling the active kinase.

Synthesis and characterization of an adsorptive Schiff base-chitosan nanocomposite for removal of Pb(II) ion from aqueous media.

A new magnetic chitosan-(2-iminothiophenol methyl)benzaldehyde Schiff base-based adsorbent (MCS-ITMB) was synthesized to be effective adsorbent for adsorption of Pb+2 from aqueous solutions. The adsorbent was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS), vibrating sample magnetometer (VSM) and X-ray Diffraction (XRD). Batch adsorption experiments were done under various conditions, such as adsorbent dose, pH, and contact time. The equilibrium data were fitted to Langmuir and Freundlich isotherm models. The maximum monolayer capacity obtained from the Langmuir isotherm was 134.10 mg/g. The MCS-ITMB was found to be regenerated effectively up to five efficient cycles of adsorption/desorption processes. The mechanism for Pb+2 adsorption onto MCS-ITMB involved the interactions of N, O and S atoms and also aromatic rings with heavy metal followed by their adsorption on the MCS-ITMB.

A Comparison Between the Effects of Preloading with Ringer's Solution and Voluven on Hemodynamic Changes in Patients Undergoing Elective Cesarean Section Under Spinal Anesthesia.

INTRODUCTION: The most common complications after spinal anesthesia for Cesarean section is hypotension. Administration of intravenous crystalloid or colloid fluid before the induction of anesthesia is a way to prevent it. AIM: The aim of this study was to compare the effects of preloading with ringer's solution and Voluven on hemodynamic changes in patients underwent elective Caesarean section under spinal anesthesia. METHODS: This study was conducted on 70 pregnant women. They were randomly divided into two groups of 35. Group I received 10 ml/kg Ringer's solution (R group) and group II received 10 ml/kg Voluven (V group) over 15 min before spinal anesthesia. Mean SBP, DBP, MAP, HR, SPO2, mean Apgar of newborn at 1 and 5 minutes after birth, mean blood pH and analysis of umbilical venous blood gases of newborns, prevalence of nausea and vomiting, and the rate of shivering and its severity were recorded in the both groups. RESULTS: Blood pH and analysis of blood gases and Apgar of newborn at 1 and 5 minutes after birth were similar in both groups. Shivering did not differ significantly between the two groups. Level of anesthesia and the incidence of nausea and vomiting in the R group were significantly higher than those in the V group (P=0.041 and P=0.029, respectively). CONCLUSION: The administration of both crystalloid and colloid fluids were effective in preventing the hypotension, although the use of Voluven was preferred to Ringer with respect to the level of the blockade and the incidence of nausea and vomiting.