Reaction Fragment Research Articles

Quantitative evaluation of H-donating abilities of C(sp3)-H bonds of nitrogen-containing heterocycles in hydrogen atom transfer reaction.

Nitrogen-containing heterocycles are an important class of antioxidants, and their reactivity and selectivity in hydrogen atom reactions have attracted significant interest from chemists. In this work, the kinetics of hydrogen atom transfer reactions from C(sp3)-H bonds of 28 nitrogen-containing heterocycles, oxygen-containing heterocycles, alicyclic amines and cycloalkanes, which were denoted as XH, to the CumO˙ radical, were investigated. The characteristic physical parameter of the substrate, i.e., the thermo-kinetic parameter ΔG≠o(XH), was determined using the kinetic equation [ΔG≠XH/Y = ΔG≠o(XH) + ΔG≠o(Y)] to quantitatively evaluate the H-donating ability of XH. The effects of the substrate structure, substituent attached to the nitrogen atom, and ring size on the H-donating ability were discussed carefully. By comparing the H-donating abilities of cycloalkanes, alicyclic amines and nitrogen/oxygen-containing heterocycles, the influence of the introduction of N, O, or carbonyl groups in the carbon ring on the H-donating ability of C(sp3)-H bond was determined. The electronic, steric and stereo-electronic effects of the groups were also discussed. Herein, we not only quantitatively determined the H-donating ability of the substrate, but also provided ideas for the synthesis of new antioxidants.

Study of plasma activated water and secondary effects on water using gamma radiation with FTIR in seeds germinations

Plasma activated water (PAW) and gamma radiation have been arduously used in many horticultural implementations; especially in increasing plant germination rates and general growth advancements. Attention has to be paid to both the effect of PAW and gamma radiation. The detailed chemical composition and appearance of tap water and distilled water that has been stimulated by plasma and gamma radiation on seed germination using Fourier transform infrared spectroscopy (FTIR) technique and optical emission spectroscopy (OES) are to be analysed. The result found that one important property of air plasma treatment on water is the creation of reactive atom species such as oxygen (O), Nitrogen (N) also known as RONS, as well as other ion molecules radical to water. Whilst gamma radiation can directly induce and generate water molecules radicals by its strong electromagnetic fields.

Atmospheric chemistry of methoxyflurane: Reaction with Cl atoms and further degradation

AbstractA dual‐level direct dynamics technique is used to explore the kinetic properties of the reaction of Cl atoms with methoxyflurane (CH3OCF2CHCl2). The energy profiles of two reaction channels of the two conformers are refined with the interpolated single‐point energies (ISPE) method at the CCSD(T)/M06‐2X level. The canonical variational transition state theory (CVT) with a small‐curvature tunneling (SCT) correction is used to assess the rate coefficients over a wide temperature range (250–500 K) in order to get accurate results. At a temperature of 296 K, the calculated CVT/SCT rate coefficient kCl = 2.71 × 10−13 cm3 molecule−1 s−1 is found to be in reasonably good agreement with the experimental result. Our calculations demonstrate that CH3OCF2CHCl2 + Cl → CH2OCF2CHCl2 + HCl (R1) reaction is the key pathway and a prominent conduit for CH3OCF2CHCl2 degradation in the troposphere. The atmospheric loss of C•H2OCF2CHCl2 and CH3OCF2C•Cl2 radicals are discussed. The rate coefficient value of the oxidation of the primary product HC(O)OCF2CHCl2 with the Cl atoms is 1.8 × 10−14 cm3 molecule−1 s−1, and for the first time, the rate coefficient of HC(O)OCF2CHCl2 + OH reaction has also been reported here.

DNA TYPING BY TELOMERASE REVERSE GENE TRANSCRIPTASE (TERT)

The length of the telomeric DNA and polymorphism of the TERT (Telomerase Reverse Transcriptase) gene can be the basis for the development of molecular genetic markers for the productive traits of agricultural animals, in particular pigs.
 The purpose of the work was to analyze the databases of the primary structure of the pig TERT gene, to determine single nucleotide polymorphisms (SNPs), to develop a DNA system for animal typing based on the TERT gene.
 Samples of biomaterials (blood, bristles) for DNA typing were selected from the leading farms of Ukraine in groups of 4 breeds of pigs and hybrid animals. Isolation of DNA from biomaterial was carried out using the Chelex 100 reagent. Genotyping of animals by the telomerase locus was carried out on the basis of standard methods of polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The alignment of nucleotide sequences during the analysis of the primary structure of the TERT gene was carried out using the MegaX software and the Blast service. Design of the structure of oligonucleotide primers for PCR was carried out using the computer program Primer3Plus.
 During the development of the method of pigs genotyping according to TERT gene, a database analysis was carried out regarding the primary structure of the gene, a region of the gene with a significant number of SNPs was identified, and oligonucleotide primers were designed for PCR amplification of this region of the gene. The study presents the conditions of amplification of the TERT gene fragment, its cleavage by restriction endonuclease RsaI at the location of SNP rs698799571, electrophoresis of the obtained restriction DNA fragments in an 8% polyacrylamide gel, and the genotypes of the animals are also determined. The developed DNA typing technique for the TERT gene was used to analyze its polymorphism in groups of 4 purebred pigs and a group of hybrid anjmals. Monomorphic homozygous TERTAA genotype was present in purebred pigs. The polymorphism of the TERT gene by SNP rs698799571 was detected in a group of pigs of the final Irish hybrid (LW x L) x Maxgro (TERTAT genotype).
 Considering the fact that studies on the telomerase gene and determination of the TERT polymorphism for SNP rs698799571 in pigs have not yet been conducted in Ukraine, the developed technique of DNA typing by the telomerase gene has a perspective for further determination of the distribution of alleles and genotypes in domestic and imported breeds, as well as in marker-associated selection.

Association of eNOS gene 4a/4b VNTR and T786C polymorphism with Crimean-Congo hemorrhagic fever

The most common viral hemorrhagic fever is Crimean-Congo hemorrhagic fever (CCHF). Endothelial nitric oxide synthase (eNOS) gene polymorphisms have been linked to both hemorrhagic fevers and viral diseases. The study’s goal is to evaluate if the eNOS gene 4a/4b and T786C polymorphisms are related to CCHF. The study included 54 CCHF RNA-positive patients and 60 control subjects. The Bosphore CCHF virus Quantification Kit v1 was used to obtain CCHF RNA, and the Magnesia 16 isolation device was used to isolate DNA (Anatolia Gene works, Turkey). Polymerase chain reaction and restriction fragment length polymorphism were used to genotype the samples. The frequency of the eNOS 4a/4a, 4a/4b, and 4 b/4b genotypes in patients and the control was 6.6% versus 1.7%, 37.0% versus 43.3%, and 57.4% versus 55%, respectively. 4a: 24.07% of patients and 23.33% of controls; and 4 b: 75.92% of patients and 76.66% of controls. The frequency of the eNOS-786 T/C, T/T, T/C, and C/C genotypes in patients and the control group was 35.2% versus 68.3%; 51.9% versus 26.73%; and 13.0% versus 5.0%, respectively. The allele and genotype frequencies of the eNOS T786C variant differ statistically between patients and the control (p < 0.05). The eNOS T786C variant could be a genetic determinant for susceptibility to CCHF. To our knowledge, this is the first study to figure out the association between eNOS gene T786C polymorphisms and CCHF disease.

A ReaxFF molecular dynamics study of polycyclic aromatic hydrocarbon oxidation assisted by nitrogen oxides

Fossil fuel-derived soot poses a persistent problem. A joint reduction is conducted via the reaction between NOx and soot. The underlying reaction mechanisms of large polycyclic aromatic hydrocarbons (PAHs), as well as the interactions between O2, NO and NO2, have been extensively investigated by ReaxFF molecular dynamics simulations for the first time. The pyrolysis and oxidation of coronene are conducted at 2500 K and 50 atm. Coronene in the pyrolysis system first experiences dehydrogenation reactions and subsequently undergoes recombination reactions, leading to the formation of large PAHs. Among the three oxidizers, NO2 is the strongest in coronene oxidation, followed by NO and O2. Meanwhile, the O radical is identified as the key species for PAH oxidation. In the presence of O2, the formation of O radicals requires the assistance of H radicals that are formed by the dehydrogenation of PAHs, which retards the oxidation process. In the presence of NO, O radicals can be directly formed via reactions of NO → N+O and N + NO ⇌ N2 + O. NO2 first undergoes a decomposition reaction: NO2 → NO + O, followed by NO decomposition. O-addition and N-addition, as well as subsequent fragmentation reactions including the generation of COx and (H)CN are important routes in PAH oxidation. Furthermore, compared to NO, NO2 provides more O radicals that significantly accelerate PAH oxidation. This study provides fundamental insight into PAH oxidation that may help to design strategies to inhibit soot and NOx emissions at the source.

Erythrose and Threose: Carbonyl Migrations, Epimerizations, Aldol, and Oxidative Fragmentation Reactions under Plausible Prebiotic Conditions.

The prebiotic generation of sugars in the context of origins of life studies is of considerable interest. Among the important intramolecular processes of sugars are carbonyl migrations and accompanying epimerizations. Herein we describe the carbonyl migration-epimerization process occurring down the entire carbon chain of chirally pure d-tetroses sugars under mild conditions. Employing chirally pure 1-13 C-erythrose, 4-13 C-erythrose and 1-13 C-threose, we (1) identify all the species formed as the carbonyl migrates down the four-carbon chain and (2) assess the rates associated with the production of each of these species. Competing aldol reactions and oxidative fragmentation processes were also observed. Further observations of self-condensation of glycolaldehyde mainly yielding 2-keto-hexoses (sorbose and tagatose) and tetrulose also provides a basis for understanding the effect of carbonyl migrations on the product distribution in plausible prebiotic scenarios.

Synthesis and characterization of phosphorus-containing polymers for the generation of polymer-derived ceramics

Phosphorus-containing polymer networks as precursors to polymer-derived ceramics were prepared using a combination of three monomers (1,3,5-triallyl-1,3,5-triazine-2,4,6-trione or 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane, tetraethylene glycol diallyl ether, and isobutyl phosphine). By varying the stoichiometry of these components, it was observed that key properties such as thermal stability, swellability, and ceramic yield after pyrolysis can be modified at will. Optimal stoichiometries to achieve the highest ceramic yields upon pyrolysis, while maintaining swellability, were determined. Cobalt was introduced into the networks by reaction of the tertiary phosphine fragments in the material with CpCo(CO)2. After pyrolysis of the metalated polymers at 800 °C, the resulting ceramics were characterized using scanning electron microscopy-energy dispersive X-ray and X-ray photoelectron spectroscopy.

Impact of HAC evolution on the formation of small hydrocarbons in the Orion Bar and the Horsehead PDRs

ABSTRACT We study evolution of hydrogenated amorphous carbon (HAC) grains under harsh UV radiation in photodissociation regions (PDRs) near young massive stars. Our aim is to evaluate the impact of the HAC grains on formation of observed small hydrocarbons: C2H, C2H2, C3H+, C3H, C3H2, C4H, in PDRs. We developed a microscopic model of the HAC grains based on available experimental results. The model includes processes of photo and thermo-desorption, accretion of hydrogen and carbon atoms and subsequent formation of carbonaceous mantle on dust surface. H2, CH4, C2H2, C2H4, C2H6, C3H4, C3H6, C3H8 are considered as the main fragments of the HAC photodestruction. We simulated evolution of the HAC grains under the physical conditions of two PDRs, the Orion Bar and the Horsehead nebula. We estimated the production rates of the HAC’ fragments in gas phase chemical reactions and compared them with the production rates of fragments due to the HAC destruction. The latter rates may dominate under some conditions, namely, at AV = 0.1 in both PDRs. We coupled our model with the gas-grain chemical model MONACO and calculated abundances of observed small hydrocarbons. We conclude that the contribution of the HAC destruction fragments to chemistry is not enough to match the observed abundances, although it increases the abundances by several orders of magnitude in the Orion Bar at AV = 0.1. Additionally, we found that the process of carbonaceous mantle formation on dust surface can be an inhibitor for the formation of observed small hydrocarbons in PDRs.

Energy release and product ion fragmentation in proton transfer reactions of N2H+ and ArH+ with acetone*

Proton transfer reaction mass spectrometry has a so far little exploited potential for the analysis of high-purity process and inert gases. In order to protonate impurities like saturated hydrocarbons, precursor ions with very low proton affinity must be used, which in turn leads to a large energy release upon protonation of molecules with high proton affinity, potentially causing fragmentation of the product ions. To explore the potential of low-proton affinity precursor ions like ArH+ and N2H+ for analytical purposes, we studied their gas-phase reactions and kinetics with acetone by Fourier transform ion cyclotron resonance (FT–ICR) mass spectrometry. The dominant product ion in both cases is protonated acetone, but fragment ions formed include C2H3O+, C3H5 + and CH3O+, which are formed in higher abundance with ArH+ compared to N2H+. The reaction efficiencies are determined to be close to 100%. Quantum chemical calculations reveal energetically favorable reaction pathways and explain the loss of water leading to the formation of C3H5 +, as well as loss of methane to yield C2H3O+ via dissociative proton attachment, which corresponds to the main product in the EI mass spectrum of acetone. Formation of protonated formaldehyde CH3O+ involves rearrangement of the C–C bonds to eliminate ethylene.

Study of frequency and inheritance model of ACE1 I/D and ACE2 rs2285666 polymorphisms in COVID-19 patients with varying severity of lung involvement and its effect on serum cytokines levels.

The angiotensin-converting enzyme (ACE) has been shown to play a role as a receptor for the COVID-19 virus. This virus usually gets into cells and infects them by attaching to their glycoprotein receptors, which are found on the ACE2 receptor. The aim of this study was to evaluate the frequency and inheritance of ACE1 I/D and ACE2 rs2285666 polymorphisms in COVID-19 patients with varying severity of lung involvement and its effect on serum cytokines levels of interleukin (IL)-1 and IL-6 and laboratory parameters. One hundred eighty-fiveCOVID-19 patients were grouped according to the severity of lung involvement. (I/D) polymorphism of the ACE1 gene and rs2285666 polymorphism of the ACE2 gene were determined by single specific primer-polymerase chain reactionand restriction fragment length reaction-polymerase chain reactionmethods, respectively. Serum levels of IL-1 and IL-6 were also measured by the enzyme linked immunosorbent assay technique. No statistically significant association of ACE2 rs2285666 polymorphism genotypes and ACE1 I/D with the severity of lung involvement was noted. However, there was a statistically significant association between I/D ACE1 polymorphism genotypes and IL-6, white blood cells (WBC), and neutrophil-to-lymphocyte ratio (NLR) levels. Also, there was no statistically significant association between rs2285666 polymorphism genotypes and patients' blood oxygen saturation level, IL-6, IL-1β, lactate dehydrogenaseactivity, WBC count, and NLR. In patients with COVID-19, the rs2285666 polymorphism of the ACE2 gene and the I/D polymorphism of the ACE1 gene were not significantly associated with the severity of COVID-19 disease and serum IL-6 and IL-1 cytokine levels.

Differentiation of Seven Isomeric n-Pentylquinoline Radical Cations Based on Energy-Resolved Medium-Energy Collision-Activated Dissociation.

Asphaltenes, a major and undesirable component of heavy crude oil, contain many different types of large aromatic compounds. These compounds include nitrogen-containing heteroaromatic compounds that are thought to be the main culprit in the deactivation of catalysts in crude oil refinery processes. Unfortunately, prevention of this is challenging as the structures and properties of the nitrogen-containing heteroaromatic compounds are poorly understood. To facilitate their structural characterization, an approach based on ion-trap collision-activated dissociation (ITCAD) tandem mass spectrometry followed by energy-resolved medium-energy collision-activated dissociation (ER-MCAD) was developed for the differentiation of seven isomeric molecular radical cations of n-pentylquinoline. The fragmentation of each isomer was found to be distinctly different and depended largely on the site of the alkyl side chain in the quinoline ring. In order to better understand the observed fragmentation pathways, mechanisms for the formation of several fragment ions were delineated based on quantum chemical calculations. The fast benzylic α-bond cleavage that dominates the fragmentation of analogous nonheteroaromatic alkylbenzenes was only observed for the 3-isomer as the major pathway due to the lack of favorable low-energy rearrangement reactions. All the other isomeric ions underwent substantially lower-energy rearrangement reactions as their alkyl chains were found to interact mostly via 6-membered transition states either with the quinoline nitrogen (2- and 8-isomers) or the adjacent carbon atom in the quinoline core (4-, 5-, 6-, and 7-isomers), which lowered the activation energies of the fragmentation reactions. The presented analytical approach will facilitate the structural characterization of nitrogen-containing heteroaromatic compounds in asphaltenes.

Homozygous deletion of exon 7 in SMN1 gene without phenotypic features of spinal muscular atrophy

Spinal muscular atrophy (SMA)(OMIM#:253300) is an autosomal recessive disorder, resulting in symmetrical progressive weakness of skeletal and respiratory muscles and atrophy. The corresponding gene for the disease is the survival motor neuron 1 (SMN1) and SMN2 genes. Homozygous deletion of SMN1 exons is the most common underlying cause of the disease, and SMN2 copy numbers modify the disease phenotype. However, homozygous deletion of exon 7 of SMN1 in a completely asymptomatic individual is an extremely rare finding. The present report discusses a case of homozygote deletion of exon 7 of SMN1 in a healthy female. A healthy couple with a family history of affected family members with SMA was referred for genetic counseling. Genomic DNA was extracted from the peripheral blood of the couple and the copy number of exon 7 of the SMN1 gene was assessed for using real-time polymerase chain reaction (PCR) and PCR-Restriction fragment length polymorphism (RFLP). Assessment of SMN1-related ct in the female compared with control samples showed that the female had a homozygous deletion in the SMN1 gene. PCR-RFLP and gel electrophoresis results also confirmed the homozygous deletion of exon 7 in the female SMN1 gene. Conclusion: According to the results of this study and also other findings in previous studies, the lack of symptoms in the female with biallelic deletion of SMN1 may be related to the presence of SMN2 copies or other modifier genes.

Electrochemical properties and dissolved behavior of laser solid formed Ti6Al4V alloy in NaCl solution with different current densities

The hybrid manufacturing process of additive manufacturing (AM) and electrochemical machining (ECM) is a new approach to advanced manufacturing technology. The feasibility of using ECM to machine an as-deposited Ti6Al4V alloy fabricated by the laser solid forming (LSF) method of AM was investigated in 15 wt.% NaCl solution. As the machining current density increased, the material removal rate increased linearly, and the current efficiency dropped from 140% to 93%. The current efficiency over 100% at low current densities was attributed to the electrochemical reactions of atoms in lower valence states. The microdissolved grooves, resulting from selective preferential dissolution of the α phase, were shallowed when machined at a higher current density (>3 A cm −2 ) and are attributed to the weakening of the galvanic effect at higher machining voltages. Additionally, the dissolved surface topography exhibited the worst waviness at the delimited current density of 10 A cm −2 , and the surface waviness decreased rapidly as the current density increased in the positive delimited range. Considering the machining efficiency and the surface quality of ECM, the as-deposited Ti6Al4V machined at a current density of 40 A cm −2 will be the preferred ECM current parameter.

Benchmarking quantum chemistry compound methods for the temperature‐dependent thermochemical data of SixHy and SixFy series

AbstractAccurate thermochemical data of SixHy and SixFy series is a prerequisite for high‐end materials design. In this study, the standard enthalpies of formation () of SixHy and SixFy were calculated from atomization and isodesmic reactions using the composite methods CBS‐QB3, G3, G4, W1U, W1BD, and W2‐F12. Second, their temperature‐dependent thermochemical parameters (∆𝑓𝑆θ and Cp) are derived from the optimized geometries and frequency calculation at B3LYP/cc‐pV(T + d)Z level. In addition, this paper uses nonexpert‐user methods (CBS‐QB3, G3, G4, W1U and W1BD) to compare the calculated with recommended values of Active Thermochemical Table, Burcat database, and W2‐F12 calculation results. The accuracy of these nonexpert‐user methods are interpreted in terms of descriptive statistics. The results show that: (1) the accuracy rank of individual compound methods is as follows: CBS‐QB3 &gt; W1BD &gt; W1U &gt; G4 &gt; G3; (2) for Si/H/F compounds, three combination methods, CBS‐QB3/G4/W1U or CBS‐QB3/G4/W1BD, and two combination methods, G4/W1U or G4/W1BD, were quite powerful, and the weighted results could reproduce the recommended values within “near‐chemical‐accuracy,” (3) the popular W1BD and W1U methods give highly erroneous results, indicating that one should not apply these methods in isolation unless other error‐cancellation strategies are collocated indicated.

Performance and mechanism study of Ce2(SO4)3 for methane chemical looping partial oxidation

Partially oxidizing methane into syngas via a two-step chemical looping scheme was a promising option for methane transformation. Ce2(SO4)3 was selected to explore the performance and mechanism of methane chemical looping partial oxidation (CLPOM) to syngas. Thermodynamic and kinetic analysis forecast the Ce2(SO4)3 as a promising candidate for CLPOM. Compared with literature, Ce2(SO4)3 not only had an outstanding syngas selectivity, but also an appropriate CH4 conversion and molar ratio, and CH4 conversion could reach 90.5 % of thermodynamic result. As revealed via characterization, Ce2(SO4)3(102) surface had the highest peak intensity and the migration of lattice oxygen played an important role in CLPOM. Some of them were tend to agglomeration and these small particles were less than 5 μm. Density functional theory calculations demonstrated that CH4 series dehydrogenation products tended to adsorb at O site and CH3 → CH2 + H was the rate-determining step. The reaction of surface lattice oxygen atoms and migration of the internal lattice oxygen atoms could inhibit carbon deposition, promote CH4 conversion and syngas generation in experiment. Compared with NiO, Ce2(SO4)3 had a lower energy barrier of lattice oxygen migration, which could increase the reaction rate.

Research of spallation reaction on plutonium target irradiated by protons with energy of 660 MeV

Relevance. This paper describes the measurement of the cross sections of the fission and fragmentation reactions of a plutonium target irradiated with a series of protons characterized by an energy of 660 MeV at the Phazotron accelerator of the Joint Institute for Nuclear Research. Purpose. The experiment focuses on the determination of short-lived radionuclides. Methods. The experimental sample was measured in offline mode using gamma spectrometry with HPGe detector. The reaction rates of the formed residual nuclei were studied. The products of spallation reaction were determined with the help of the direct kinematics method. The DEIMOS32 software was used to process γ-spectra. Results. As a result of the interaction of nuclear elements with protons, nuclei were formed in the 239Pu sample. Those nuclei were identified using the TJ02000321–V3 software. The reaction products were identified based on gamma energies, intensity and half-life after the measurement set. During the study of the gamma spectra determined for the irradiated plutonium target, it was possible to establish 50 gamma lines and reveal 31 nuclides by energy and half-life cycles from 14.4 m to 3.19 h. The measured nuclear reaction cross-sections can serve as reference data for theoretical simulations of the interaction of protons with 239Pu and they can be a supplement to the nuclear databases. Conclusions. The obtained experimental result is compared with the simulation on MCNP 6.1. The data overall correspond to the expected range, but it still needs more evaluation. The next logical step is to search for primary products (mother nuclei) and compare the obtained experimental data with the results of computer simulations

Diabatic potential energy surfaces and semiclassical multi-state dynamics for fourteen coupled 3 A′ states of O3

Dissociation and energy transfer in high-energy collisions of O2 play important roles in simulating thermal energy content and heat flux in flows around hypersonic vehicles. Furthermore, atomic oxygen reactions on the vehicle surface are an important contributor to heat shield erosion. Molecular dynamics modeling is needed to better understand the relevant rate processes. Because it is necessary to model the gas flows in high-temperature shock waves, electronically excited states of O2 and O can be populated, and molecular dynamics simulations should include collisions of electronically excited species and electronically nonadiabatic collisions. This requires potential energy surfaces and state couplings for many energetically accessible electronic states. Here we report a systematic strategy to calculate such surfaces and couplings. We have applied this method to the fourteen lowest-energy potential energy surfaces in the 3 A′ manifold of O3, and we report a neural-network fit to diabatic potential energy matrix (DPEM). We illustrate the use of the resulting DPEM by carrying out semiclassical dynamics calculations of cross sections for excitation of O2 in 3 A′ collisions with O at two collision energies; these dynamics calculations are carried out by the curvature-driven coherent switching with decay of mixing method.

Microfluidic devices employing chemo- and thermotaxis for sperm selection can improve sperm parameters and function in patients with high DNA fragmentation.

Conventional sperm processing uses centrifugation has a negative effect on sperm parameters and DNA integrity. We designed and fabricated a novel microfluid device based on chemotaxis and thermotaxis, and compared it with the swim-up method. Twenty normal samples with high DNA fragmentation were included. Each sample was divided into four groups: Group 1, control, Group 2: sperm selection by thermotaxis, Group 3: sperm selection by chemotaxis, and Group 4: sperm selection with thermotaxis and chemotaxis. We used cumulus cells in a microfluid device to create chemotaxis, and, two warm stages to form a temperature gradient for thermotaxis. The spermatozoa were assessed based on the concentration, motility, and fine morphology using Motile Sperm Organelle Morphology Examination, mitochondrial membrane potential (MMP), acrosome reaction (AR), and sperm DNA fragmentation. Concentration (22.40 ± 5.39 vs. 66.50 ± 19.21; p < 0.001) and DNA fragmentation (12.30 ± 3.96% vs. 17.95 ± 2.89%; p < 0.001) after selection in the chemotaxis and thermotaxis microfluid device were significantly lower than control group. The progressive motility (93.75 ± 4.39% vs. 75.55 ± 5.86%, p < 0.001), normal morphology (15.45 ± 2.50% vs. 10.35 ± 3.36, p < 0.001), MMP (97.65 ± 1.81% vs. 94 ± 3.89%, p=0.02), and AR status (79.20 ± 5.28% vs. 31.20 ± 5.24%, p < 0.001) in the chemotaxis and thermotaxis microfluid device were significantly increased compared to control group. According to these findings, spermatozoa that have penetrated the cumulus oophorus have better morphology and motility, as well as acrosome reactivity and DNA integrity.

Clinical characterizations of three adults with genetically confirmed spinal muscular atrophy: a case series

BackgroundSpinal muscular atrophy is a recessively inherited autosomal neuromuscular disorder, with characteristic progressive muscle weakness. Most spinal muscular atrophy cases clinically manifest during infancy or childhood, although it may first manifest in adulthood. Although spinal muscular atrophy has come to the era of newborn screening and promising treatments, genetically confirmed spinal muscular atrophy patients are still rare in third world countries, including Indonesia.Case presentationsWe presented three Indonesian patients with spinal muscular atrophy genetically confirmed during adulthood. The first case was a 40-year-old male who presented with weakness in his lower limbs that started when he was 9 years old. At the age of 16 years, he could no longer walk and started using a wheelchair. He first came to our clinic at the age of 38 years, and was diagnosed with spinal muscular atrophy 2 years later. The second patient was a 58-year-old male who presented with lower limb weakness since he was 12 years old. Owing to the geographical distance and financial problems, he was referred to our clinic at the age of 56 years, when he already used a walker to walk. Lastly, the third patient was a 28-year-old woman, who was in the first semester of her second pregnancy, and who presented with slowly progressing lower limb weakness. Her limb weakness began at the age of 8 years, and slowly progressed until she became dependent on her wheelchair 8 years later until now. She had successfully given birth to a healthy daughter 3 years before her first visit to our clinic. All three patients were diagnosed with neuromuscular disorder diseases, with the differential diagnoses of Duchenne muscular dystrophy, spinal muscular atrophy, and Becker muscular dystrophy. These patients were finally confirmed to have spinal muscular atrophy due to SMN1 deletion by polymerase chain reaction and restriction fragment length polymorphism.ConclusionsMany genetic diseases are often neglected in developing countries owing to the difficulty in diagnosis and unavailable treatment. Our case series focused on the disease courses, diagnosis difficulties, and clinical presentations of three patients that finally lead to diagnoses of spinal muscular atrophy.