Isomerism Research Articles

RELATIVE CERTAINTY AS OPPOSED TO UNCERTAINTY IN THE DIAGNOSIS OF ISOMERISM

RELATIVE CERTAINTY AS OPPOSED TO UNCERTAINTY IN THE DIAGNOSIS OF ISOMERISM

Molecular modelling of the antiviral action of Resveratrol derivatives against the activity of two novel SARS CoV-2 and 2019-nCoV receptors.

The pandemic threat of COVID-19 causes serious concern for people and world organizations. The effect of Coronavirus disease on the lifestyle and economic status of humans is undeniable, and all of the researchers (biologists, pharmacists, physicians, and chemists) can help decrease its destructive effects. The molecular docking approach can provide a fast prediction of the positive influence the targets on the COVID-19 outbreak. In this work, we choose resveratrol (RV) derivatives (22 cases) and two newly released coordinate structures for COVID-19 as receptors [Papain-like Protease of SARS CoV-2 (PBD ID: 6W9C) and 2019-nCoV RNA-dependent RNA Polymerase (PBD ID: 6M71)]. The results show that conformational isomerism is significant and useful parameter for docking results. A wide spectrum of interactions such as Van der Waals, conventional hydrogen bond, Pi-donor hydrogen bond, Pi-Cation, Pi-sigma, Pi-Pi stacked, Amide-Pi stacked and Pi-Alkyl is detected via docking of RV derivatives and COVID-19 receptors. The potential inhibition effect of RV-13 (-184.99 kj/mol), and RV-12 (-173.76 kj/mol) is achieved at maximum value for 6W9C and 6M71, respectively.

Feasibility of quantitative measurement of fetal trachea and bilateral bronchial angles by ultrasound to diagnose heterotaxy syndrome in middle and late pregnancy

Objective To analyze the feasibility of prenatal ultrasound quantitative measurement of the angles between trachea and bilateral bronchi as a new diagnostic tool for fetuses with heterotaxy syndrome. Methods The angles between trachea and bilateral bronchi were measured at 18-34+6 gestational weeks for 200 fetuses with normal ultrasound findings (normal group) and 41 fetuses with heterotaxy syndrome [35 right atrial isomerisms (right group) and six left atrial isomerisms (left group)] diagnosed by ultrasound and confirmed after abortion or induction (case group) in Chongqing Health Center for Women and Children from October 2015 to December 2018. Scatter plots of left/right bronchus angle (α/β) ratios were drawn. Differences in bilateral bronchus angles between the three groups were statistically analyzed using one-way analysis of variance and paired t-test. Results In the normal group, scatter plots showed the α/β ratios were relatively constant at 0.8-1.0 with larger β than α (t=-33.14, P 0.05] and presented as bilateral right bronchial angle; in the left group, the β value decreased and was close to the α value [(147.38±3.16)° vs (148.82±5.56)°, t=-1.18, P>0.05] and presented as bilateral left bronchial angle. There were significant differences in the α and β values among the normal group, the right and left groups (all P<0.05), and the bronchial angles of the right group were both greater than those of the left group (all P<0.05). Conclusions Prenatal ultrasound measurement of the angles between trachea and bilateral bronchi can be used as an indirect indicator for the diagnosis of heterotaxy syndrome. Key words: Heterotaxy syndrome; Ultrasonography, prenatal; Trachea; Bronchi

Fetal pulmonary atresia with ventricular septal defect: echocardiographic findings, associated anomalies and chromosomal characteristics

Objective To analyze the echocardiographic findings, associated anomalies and chromosomal characteristics in fetuses with pulmonary atresia with ventricular septal defect (PA/VSD). Methods The echocardiographic data and follow-up materials were retrospectively reviewed in 30 256 fetuses from December 2012 to March 2018 in the consultation center of fetal heart disease in maternal-fetal medicine in Anzhen hospital. Of all the fetuses, 59 cases (0.19%) had PA/VSD. The echocardiographic findings, associated anomalies and chromosomal characteristics were retrospectively analyzed in all the 59 fetuses with PA/VSD. Based on whether the presence of the native pulmonary arteries and the major aortopulmonary collateral arteries (MAPCAs) or not, the PA-VSD was classified into type A, type B, and type C. Results A large ventricular defect was demonstrated in five-chamber view with 61.7% of the mean ratio of the aortic overriding. Other fetal echocardiographic features of all the 59 fetuses with PA/VSD included: the right aortic arch (n=19), reversal flow in the ductus arteriosus (n=40), MAPCAs (n=24). The classification of the PA/VSD included: type A (n=35), type B (n=5) and type C (n=19). Associated anomalies: persistent left superior vena cava (n=13), anomalous pulmonary vein connection (n=5), complete atrioventricular septal defect (n=5); single umbilical artery (n=3), right atrial isomerism (n=3). Of all the 30 cases performed chromosomal test, 3 cases had aneuploidy and 7 cases had microdeletion of chromosome. Conclusions The fetal echocardiographic findings of the PA/VSD are characteristic. For prenatal diagnosis of PA/VSD, the type of PA/VSD should be defined and chromosomal test should be performed, which can be helpful for prenatal consulting. Key words: Echocardiography; Heart septal defect, ventricular; Pulmonary atresia; Prenatal diagnosis; Chromosomal aberrations

Analysis of cardiovascular misinterpretations of prenatal ultrasound diagnosis in fetuses with heterotaxia syndrome

Objective To explore the correlation between the cardiovascular ultrasound results and pathological findings of heterotaxia syndrome, analyze the cause of the difference, and improve the prenatal cardiovascular diagnostic accuracy of heterotaxia syndrome by ultrasound. Methods According to fetal autopsy or vessel casting, the ultrasound results of 37 fetuses with heterotaxia syndrome were retrospectively analyzed. The cardiovascular misinterpretations of ultrasound were summarized in the venous-atrial segment, atrial-ventricular segment and ventricular-arterial segment. Results ①Thirty fetuses underwent autopsy and seven fetuses vessel casting were included, there were 10 fetuses with left atrial isomerism and 27 fetuses with right atrial isomerism.Only one left isomerism was misdiagnosed and the diagnostic accuracy of atrial isomerism by ultrasound was 97.3%. ②Thirty-seven fetuses with heterotaxia syndrome included 206 cardiovascular malformations. Twenty-seven misinterpretations of ultrasound were found and the rate of cardiovascular misinterpretations was 13.1%. ③The cardiovascular misinterpretations of left atrial isomerism involved 1 secondary atrial septal defect in the atrial-ventricular segment and 1 aortic atresia, 2 anomalous position of arterial duct in the ventricular-arterial segment. ④The cardiovascular misinterpretations of right atrial isomerism in the venous-atrial segment included 4 common pulmonary vein atresia, 3 anomalous hepatic venous connection, 3 total abnormal pulmonary venous drainage, 2 persistent left superior vena cava and 2 abnormal inferior cava venous drainage. The cardiovascular misinterpretations of right atrial isomerism in the atrial-ventricular segment contained 2 secondary atrial septal defect, 1 unroofed coronary sinus and 1 partial atrioventricular septal defect. The cardiovascular misinterpretations of right atrial isomerism in the ventricular-arterial segment involved 3 double-outlet right ventricle, 1 truncus arteriosus and 1 anomalous position of arterial duct. Conclusions The correspondence between ultrasound results and pathological findings about cardiovascular malformations of heterotaxia syndrome is high. The most common cardiovascular misinterpretations of left atrial isomerism involve the ventricular-arterial segment. And the most common cardiovascular misinterpretations of right atrial isomerism involve the venous-atrial segment. Key words: Ultrasonography, prenatal; Heart defects, conginatal; Heterotaxia syndrome

ORGANODIPHOSPHINES IN PtP2X2 (X = Br or I) DERIVATIVES – STRUCTURAL ASPECTS

Baeyer-VillThis review covers twenty eight monomeric Pt(η2-P2L)X2 (X = Br or I) derivatives. These complexes exist in cis- as well as trans-configurations from which the complexes with cis-configuration are more common. The organodiphosphines create wide varieties of the metallocyclic rings PNP, PC2P, PC3P, PNCNP and PC4OC4P. The mean values of Pt-L bond distances in cis-complexes are: 2.230 A (P), 2.490 A (Br) and 2.240 A (P) 2.666A (I), respectively. In the trans-complexes the values are 2.319 A (P), 2.429 A (Br) and 2.320 A (P), 2.615 A (I). The Pt-X bond distances in the cis- as well as in the trans-derivatives elongate with the covalent radius of the X atom. In addition in the cis-derivatives the Pt-X bond distances are longer than those in trans-derivatives, as a reason of higher trans-influence of P over the respective halogens. Some of the complexes are examples of distortion isomerism. Finally, the structural data of Pt(η2-P2L)X2 (X = Br or I) are compared with the values of Pt(η2-P2L)X2, complex and discussed.

Prenatal ultrasound diagnosis of unroofed coronary sinus and review of the literature

Objective To summarize the prenatal ultrasonographic characteristics of unroofed coronary sinus(URCS) for improving the prenatal echocardiography diagnostic accuracy of URCS. Methods The retrospective review for prenatal ultrasonogram of 7 fetuses was applied, which were diagnosed as URCS. The prenatal ultrasonographic characteristics of 7 fetuses with URCS were reviewed and comparatively analyzed with postpartum autopsy findings or postnatal echocardiography. The relevant literatures referring to the prenatal diagnosis of URCS were reviewed. The experience of prenatal diagnosis of URCS were summarized. Results In 7 cases with URCS, 5 cases of completely URCS were associated with right atrial isomerism syndrome and confirmed by postpartum autopsy, and 2 cases of partially URCS were only with persistent left superior vena cava and confirmed by postnatal echocardiography. The karyotype analysis of 2 cases of partially URCS on amniotic fluid was normal. Conclusions There are some characteristic signs in ultrasonic features of URCS. URCS can be diagnosed by prenatally ultrasonography. A long axial section of the coronary sinus is the most important view for prenatal ultrasonic diagnosis of URCS. Key words: Ultrasonography, prenatal; Fetus; Unroofed coronary sinus

Prenatal ultrasonic diagnosis of fetal isolated levocardia

Objective To investigate the clinical application valve of prenatal ultrasound in diagnosis of fetal isolated levocardia(IL). Methods Thirty-eight IL fetuses diagnosed in three prenatal diagnosis centers from 2000 to 2016 were reviewed with their prenatal ultrasound features and cardiac and extracardiac malformations. Results Thirty-eight IL cases included 19 cases of left isomerism(LI), 14 cases of right isomerism(RI) and 5 non-classified cases. The overall incidence of malformations in IL patients was 97.4% with 94.7% in LI patients and 100% in RI patients. The incidence of cardiac malformations was 92.1% with 84.2% in LI patients and 100% in RI patients. The most common congenital heart diseases were: right ventricle outlet obstruction, univentricular physiology and atrioventricular septal defect. Anomalous pulmonary venous connection was more commonly seen in LI patients than in RI patients. The most common extracardiac malformation was duodenal obstruction(86.9%). Inferior vena cava interruption and polysplenia were more commonly seen in LI patients.Juxtaposition of aorta and inferior vena cava and asplenia were more commonly seen in RI patients. Conclusions IL is very rarely seen in population with high incidence of congenital heart diseases and extracardiac malformations. Key words: Ultrasonography, prenatal; Isolated levocardia; Heart defect, congenital; Fetal malformation

Application of diversified teaching methods in teaching of Organic Chemistry

The content of optical isomerism is the difficult point of organic chemistry teaching, and so case-based learning (CBL), theoretical-experimental integration teaching method and micro class teaching methods are tried to be used in classroom teaching according to the actual teaching situations. For CBL teaching method, the course is guided by the step of introduction-question-discussion and summary-exten-sions; For theoretical-experimental integration teaching method, combined with the theory class, the two experiments including the determination of optical rotation and organic molecular model are set for the opti-cal isomer content, to enhance the students' understanding of theoretical knowledge through the hands-on operation; For micro class teaching method, the key and difficult points of this chapter are dug out and about 10 minutes of video are recorded by using common video software before class, which are introduced in the classroom or provided to students after class for repeated watching, to deepen the students' understanding of the concept and phenomenon of optical isomers. In brief, it is important to combine various teaching method to improve the classroom instructing effectively and stimulate the students' interest in organic chemistry. Key words: Optical isomerism; Case-based learning; Teaching method; Theoretical-experi-mental integration teaching method; Micro class; Molecule model

Prenatal ultrasound diagnosis of fetal abnormalies of the inferior vena cava

Objective To explore the value of prenatal ultrasound in diagnosis of fetal anomalies of the inferior vena cava (IVC) and to improve the prenatal detection rate. Methods Fourteen cases of fetal anomalies of IVC examined by prenatal ultrasound from June 2013 to April 2016 in our hospital were analyzed, the prenatal ultrasonographic characteristics through abdominal transverse, coronal and IVC long axis were summarized, and were compared with the autopsy results. Results In 14 cases of anomalies of IVC, 12 cases were isolated IVC interruption, and 2 cases were high confluence of IVC. In 12 cases of isolated IVC interruption, 9 cases compicated by left isomerism, 1 case complicated by sistus inversus viscerum, 1 case complicated by isolated IVC interruption; 2 cases of high confluence of IVC were combined with multiple malformations, including 1 case of chromosome 18-trisomy syndrome.Thirteen cases were confirmed by pathology, and 1 case of the high confluence of IVC lost follow-up. Conclusions Fetal anomalies of IVC have characteristic manifestations in prenatal ultrasonographic. When detecting the IVC interruption, left isomerism should be highly suspected. Key words: Ultrasonography, prenatal; Fetus; Abnormalies of the inferior vena cava

Value of MRI in the diagnosis of fetal aortic arch anomalies

Objective To explore the value of MRI in the diagnosis of fetal aortic arch anomalies. Methods We retrospectively collected 10 fetuses with aortic arch anomalies indicated by prenatal ultrasound and underwent MR examination and were subsequently proven by autopsy or post-birth follow-up from 320 pregnant women. We focused on the observations of the location of the aortic arch and brachiocephalic artery anomalies, the locations of the liver and stomach in the abdominal cavity, and the large vessels in abdomen. The above-mentioned finding were compared with prenatal ultrasound and follow-up findings. Results Of 10 cases, right aortic arch with aberrant left subclavian artery was seen in 7 cases, right aortic arch with the mirror branch, left aortic arch with aberrant right subclavian artery, right aortic arch with aberrant left subclavian artery combined with cervical aortic arch and double aortic arch was seen in 1 case, respectively. All aortic arch anomalies detected by MRI were consistent with post-birth or autopsy findings. Ultrasound misdiagnosed aortic branch malformation in 5 places, which included right aortic arch but misdiagnosed aberrant left subclavian artery in 2 cases, right aortic arch never diagnosed mirror branch anomaly in 1 case, right aortic arch with left subclavian artery misdiagnosed cervical aortic arch in 1 case, left atrial isomerism but misdiagnosed left aortic arch with aberrant right subclavian artery in 1 case; One double aortic arch was misdiagnosed as right aortic arch with aberrant left subclavian artery in ultrasound. Conclusion Fetal cardiovascular MRI is an effective and supplementary examination to complement ultrasound in diagnosis of fetal aortic arch anomalies. Key words: Fetus; Aorta,thoracic; Vascular malformations; Magnetic resonance imaging

Left Atrial Isomerism in an Adult

Atriyal izomerizm her iki atriyumun ve apendikslerinin benzer gorunumde olmasi ile ortaya cikar. Genellikle cocukluk caginda tani konularak tedavi edilir. Sistemik ve pulmoner venoz donus anomalileri, atrioventrikuler septal defekt, ventrikuloarteryel diskordans siklikla eslik eden kardiyak patolojiler olup, situs ambiguus da bulunabilir. Sol atriyal izomerizmde genellikle sinus nodu bulunmaz, % 75’inde inferior vena kava, azygos devamliligi ile drene olurken; hepatik venler sag atriyuma ayri acilirlar. Hastalarin 2/3’unde bilateral superior vena kava mevcuttur ve bunlardan biri koroner sinuse drene olur. Koroner sinuse drene olan persistan sol superior vena kava, inferior vena kava agenezisinin eslik ettigi atrial septal defekt tanisi ile klinigimize basvuran 20 yasinda erkek hastada yapilan kardiyak manyetik rezonans incelemede hepatik venlerin sag atriyuma drene oldugu ve inferior vena cava agenezi tesbit edildi.(Resim1) Hasta mevcut bulgularla sol atrial izomerizm tanisi ile operasyona alindi. Perikardiyotomi sonrasi, sag atriyumun morfolojik yapisinin sol atriyum gibi uzun, ince dikdortgen seklinde oldugu goruldu. (Resim2A) Sag atriyum ekarte edilince inferior vena kavanin olmadigi ve hepatik venlerin sag atriyuma drene oldugu goruldu. (Resim2B) Ilimli hipotermiyi takiben dortlu venoz kanulasyon (selektif superior vena kava, persistan sol superior vena kava, iki hepatik ven) ile kardiyopulmoner baypasa girildi. Pulmoner venler sol atriyuma drene olacak sekilde perikardiyal patch ile tek yama teknigi kullanilarak tamir edildi. Atriyotominin kapatilmasini takiben operasyon sonlandirildi. Takiplerini sorunsuz geciren hasta postoperatif 6. gunde taburcu edildi. Atriyal izomerizm eriskin yasta atriyal septal defekt tanisi nedeni ile operasyon planlanan hastanin detayli incelemesi ile tani konulabilecek konjenital kalp hastaligidir. Preoperatif tani konulmasi operasyon stratejisini belirlemede onemlidir.

Comparison of the prenatal ultrasonic features between left and right isomerism

Objective To compare the prenatal ultrasonic characteristics between left and right isomerism as referring to autopsy outcomes.Methods Between November 2007 and July 2010,fetuses with isomerism that were confirmed by autopsy,were identified from 1200 prenatal ultrasonic scans.Their abnormal spectrums and ultrasonic features were analyzed and comparied between left and right isomerism.Results A total of 18 fetuses with right isomerism and 4 fetuses with left isomerism were detected and confirmed.The major findings of the right isomerism were;viscerocardiac heterotaxy (17,94%),anomalous pulmonary venous connection (16,89%),complete atrioventricular septal defect (15,83%),juxtaposition of the descending aorta and inferior vena cava(12,67%),left persistent superior vena cava (11,61%),right aortic arch (10,56%) and univentricle (10,56%).As for the left isomerism,all had viscerocardiac heterotaxy and interruption of inferior vena cave,three of them had heart block,complete atrioventricular septal defect and hypoplasia of aorta,two of them had univentricle.Conclusions Viscerocardiac heterotaxy,complete atrioventricular septal defect,univentricle are the most common anomalies detected.Right isomerism cases usually exist with anomalous pulmonary venous connection,juxtaposition of the descending aorta and inferior vena cava as well as right aortic arch.The left isomerism cases usually have interruption of inferior vena cave,heart block and hypoplasia of aorta. Key words: Ultrasonography,prenatal; Heart defects,congenital; Atrium isomerism

Study on relation between the fetal abdominal great vessels anormalities and heterotaxy

Objective To investigate the relation between anormalities of fetal abdominal great vessels and heterotaxy, the clinical significance of screening fetal heterotaxy by the abnormalities of fetal abdominal great vessels. Methods 6532 fetuses from our hospital were scanned and the fetuses with abdominal great vessels abnormalities were included. Parameters of fetal growth, abdominal great vessels and anatomical survey were detected. Results Forty-five cases (0.7%) of fetal abdominal great vessels abnormalities were detected prenatally. Forty-two cases were confirmed postnatally, including 35 cases of heterotaxy syndrome and 7 cases of situs inversus totalis and 3 cases missed. The incidences of the abnormal fetus,heterotaxy syndrome and situs inversus totalis of the fetuses with abnormal abdominal great vessels were higher than that of the fetuses with normal abdominal great vessels, the differences were statistically significant( P＜ 0.001). The incidence of both type Ⅰ and type Ⅱ of the heterotaxy syndrome were significantly higher than that of type Ⅳ (P＜0.001). There was a high incidence of left isomerism in abnormal type Ⅰ and of right isomerism in abnormal type Ⅱ , the differences were statistically significant (P＜ 0.001). Conclusions Abnormal great vessels abnormalities have strong relations to heterotaxy and situs inversus which can be used as effective and simple indicator in screening heterotaxy syndrome. Key words: Ultrasonography, prenatal; Cardiovascular abnormalities; Situs inversus

Study on construction of public management system of traditional Chinese medical picture resources

The author made a feasible study on the construction of public management system of traditional Chinese medical picture resources based on current existence of TCM pictures.Pictorial resources of original separation,multielement,isomerism,and scattered distribution,were united by physical and logical patterns for the purpose of enhancing their availability.Public management system plat Of TCM picture resources was set up,with the characteristics of practicability,novelty,originality,and suitability for scientific research,teaching and public propagate education. Key words: Traditional Chinese medicine; Pictorial resources; Resource sharing

Structure, crystal polymorphim and rotational isomerism in prototype ionic liquid-[bmim]Cl as studied by near infrared Raman spectroscopy

Structure, crystal polymorphim and rotational isomerism in prototype ionic liquid-[bmim]Cl as studied by near infrared Raman spectroscopy

Coexistence of two distinct structures in ionic liquids: rotational isomerism of the butyl-methylmidazolium ([bmim]+) cation

Coexistence of two distinct structures in ionic liquids: rotational isomerism of the butyl-methylmidazolium ([bmim]+) cation

MRI in Evaluation of Heterotaxy Syndrome

Visceral heterotaxy is a rare congenital malformation, often associated with congenital cardiac anomalies and abnormal viscero-atrial situs. A precise diagnosis must be made during early life so that the most appropriate treatment can be selected. Spin echo magnetic resonance (MR) findings in 10 patients with heterotaxy syndrome (7 with right isomerism, 3 left isomerism) were reviewed. The MR imaging (MRI) findings of the seven cases of visceral heterotaxy with right isomerism included eparterial bronchi (n=7), ipsilateral position of the abdominal aorta and inferior vena cava (IVC) (n=3), and prominent congenital cardiac anomaly (n=7), such as common atrioventricular canal (CAVC). The MRI findings of the three cases of heterotaxy with left isomerism included interruption of IVC (n=3), engorged azygos-hemiazygos system (n=3), and hyparterial bronchi (n=3). MRI can make it possible to have an accurate and non-invasive diagnosis on patients with heterotaxy syndrome.

Synthesis and Isomerism of Monofunctional Arylated Cyclotetrasilanes

Synthesis and Isomerism of Monofunctional Arylated Cyclotetrasilanes

水素同位体交換反応における一置換安息香酸の反応性に及ぼす温度と置換基の影響

一置換安息香酸 (固体) とHTO蒸気との間で起こる水素同位体交換反応を, 温度を変えて観測した。得られた観測値にA〃-McKayプロット法を適用して反応を解析し, つぎの結果を得た。 (1) 一置換安息香酸の反応性は, その置換基の電子求引性が大きいほど大きい。 (2) この反応において, 反応定数 (ρ) の温度依存性はかなり小さい。 (3) 置換基がその物質の反応性に与える影響は固気反応より固液反応の方がかなり大きい。