Application value of color Doppler ultrasound in hemodynamic changes and fetal outcome analysis of umbilical artery and middle cerebral artery in oligohydramnios / 中国医师进修杂志

Objective@#To study the hemodynamic changes of fetal umbilical artery (UA) and middle cerebral artery (MCA) and its influence on fetal outcome using color Doppler ultrasound.@*Methods@#Fifty pregnant women who underwent color Doppler ultrasound examination in Zhejiang Xin'an International Hospital from June to December 2018 with normal prenatal examination were selected as control group, and 80 pregnant women with oligohydramnios during the same period of pregnancy were selected as observation group. Color Doppler ultrasound examination was performed on both groups of pregnant women. The results of color Doppler ultrasound examination were compared between the two groups of pregnant women, and the fetal prognosis was followed up.@*Results@#Compared with the control group, the peak systolic velocity/end diastolic velocity (S/D), resistance index (RI) and pulsatility index (PI) values of UA in the observation group were significantly increased, while the S/D, RI and PI values of MCA were significantly decreased, and there were significant differences (P < 0.05). In addition, UA of 34 cases (42.5%) in observation group had S/D ≥ 3, which was much higher than that of 8 cases (16.0%) in control group, and there was significant difference (P < 0.05). The difference between the two groups was statistically significant (P < 0.05). The incidence of fetal distress, intrauterine growth retardation (IUGR) and Apgar < 4 points in observation group were significantly higher than those in control group [26.2%(21/80) vs. 12.0%(6/50), 15.0%(12/80) vs. 2.0%(1/50), 7.5% (6/80) vs. 0], and the difference were statistically significant (P < 0.05).@*Conclusions@#Prenatal color Doppler ultrasound can accurately detect the hemodynamic indexes of UA and MCA, predict the fetal intrauterine development, evaluate the fetal outcome, and provide scientific basis for clinical diagnosis.

Application value of color Doppler ultrasound in hemodynamic changes and fetal outcome analysis of umbilical artery and middle cerebral artery in oligohydramnios / 中国医师进修杂志

study the hemodynamic changes of fetal umbilical artery (UA) and middle cerebral artery (MCA) and its influence on fetal outcome using color Doppler ultrasound. Methods Fifty pregnant women who underwent color Doppler ultrasound examination in Zhejiang Xin'an International Hospital from June to December 2018 with normal prenatal examination were selected as control group, and 80 pregnant women with oligohydramnios during the same period of pregnancy were selected as observation group. Color Doppler ultrasound examination was performed on both groups of pregnant women. The results of color Doppler ultrasound examination were compared between the two groups of pregnant women, and the fetal prognosis was followed up. Results Compared with the control group, the peak systolic velocity/end diastolic velocity (S/D), resistance index (RI) and pulsatility index (PI) values of UA in the observation group were significantly increased, while the S/D, RI and PI values of MCA were significantly decreased, and there were significant differences (P<0.05). In addition, UA of 34 cases (42.5%) in observation group had S/D≥3, which was much higher than that of 8 cases (16.0% ) in control group, and there was significant difference (P < 0.05). The difference between the two groups was statistically significant (P < 0.05). The incidence of fetal distress, intrauterine growth retardation (IUGR) and Apgar < 4 points in observation group were significantly higher than those in control group [26.2%(21/80) vs. 12.0%(6/50), 15.0%(12/80) vs. 2.0%(1/50), 7.5% (6/80) vs. 0], and the difference were statistically significant (P < 0.05). Conclusions Prenatal color Doppler ultrasound can accurately detect the hemodynamic indexes of UA and MCA, predict the fetal intrauterine development, evaluate the fetal outcome, and provide scientific basis for clinical diagnosis.

Comparison of Circumferential Pulmonary Vein Antecourt Isolation Ablation and Stepwise Linear Ablation for Treating the Patients With Atrial Fibrillation / 中国循环杂志

Objective: To compare the efifcacy and safety of circumferential pulmonary vein antecourt isolation (CPVAI) ablation and stepwise linear (SL) ablation in treating the patients with atrial ifbrillation (AF) Methods: A total of 136 AF patients with catheter ablation under EnSite 3000 guidance in our hospital were retrospectively summarized. The patients included 93 paroxysmal AF and 43 persistent AF and divided into 4 groups. Paroxysmal AF with CPVAI ablation,n=45, Paroxysmal AF with SL ablation,n=48 and persistent AF with CPVAI ablation, n=18, persistent AF with SL ablation,n=25. The differences of left atrium diameter, ablation time, X-ray exposure time, the success rate and complication were compared among different groups. Results: For 12 months follow-up study, the success rate and complication were similar between 2 ablation methods for treating both Paroxysmal AF and persistent AF patients. For Paroxysmal AF patients, both ablation methods could effectively reduce left atrium diameter,P<0.01. The SL ablation had less procedural time than CPVAI ablation,P<0.01, while the X-ray exposure time was similar between 2 ablation methods. Conclusion: Both CPVAI and SL ablation methods were effective and safe for treating AF patients.

Identification of key residues in the catalytic center JadH involved in binding substrates or catalysis of jadomycin biosynthesis / 生物工程学报

JadH is a bifunctional hydoxylase/dehydrase involved in jadomycin biosynthesis; it catalyzes a post-PKS modification reaction to convert 2,3-dehydro-UWM6 to dehydrorabelomycin. To identify the key residues involved in substrate-binding and catalysis, structural modeling and multiple sequence alignments of JadH homologs were performed to predict nine residues at the proximity of substrate. Site-directed mutagenesis of the corresponding residues and in vitro evaluation of the activities of the mutant enzymes, indicate these mutations severely reduced JadH activity. Our results indicate these residues are specifically involved in substrate-binding or catalysis in JadH.

Progress in the understanding of the function of atypical response regulators: a review / 生物工程学报

Two component system is a signal transduction system. It typically consists of a sensor histitine kinase and a cognate response regulator (RR) component. The activity of RR is regulated by a phosphorylation dependent mechanism. In recent years, the existence of atypical response regulators (ARRs), which rely on a phosphorylation independent mechanism to regulate their activity, have been recognized. ARRs are involved in the regulation of bacterial growth and development, antibiotic biosynthesis, iron transport, among others. Here we review the recent advances in the understanding of the structure and function of atypical response regulators, by using JadR1, a regulator in jadomycin biosynthesis in Streptomyces, as an example to elucidate the novel mechanism used by ARR to fine-tune its activity.

Structure and function of tonoplast Cation/H+ antiporters in plant: a review / 生物工程学报

Cation transporters play important roles in modulating the concentration of intracellular metal ions. The vacuole is an important storage organelle for many ions. Cation (Ca+)/H+ antiporters (CAXs) located at vacuolar membrane are mainly involved in the Ca2+ flux into the vacuole, and appear to be capable of transporting various divalent cations to some degree. Several CAX genes have been isolated and characterized from various plants in recent years. Four domains of plant CAXs have been identified: NRR regulates Ca2+ transport by a mechanism of N-terminal autoinhibition; Ca domain and C domain confer Ca2+ and Mn2+ specificity among CAX transporters, respectively; D domain plays a part in the regulation of cytosolic pH. AtCAXs identified in Arabidopsis thaliana are involved in the growth, development and stress adaption of plant. AtCAX3 is the mainly Ca2+/H+ transporter in response to salt stress; AtCAX2 and AtCAX4 participate in transportation and detoxicification of heavy metal ions (Cd2+, Zn2+, and Mn2+) in cells under heavy metal stress, and impact root/shoot Cd partitioning in plant. These suggest that CAX genes may be useful for nutritional enhancement of plants, and for increasing phytoremediation potential. Here, the classification, structure and function of CAXs in plants are reviewed.

Structure and function of heavy metal transporter P(1B)-ATPase in plant: a review / 生物工程学报

The regulation of the heavy-metal accumulation in vivo for plant survival is very complex. The metal cation transporter plays key roles in the metabolic process. P(1B)-ATPases are the only subgroup of P-ATPases that contribute to heavy metal homeostasis presented in most organisms. Arabidopsis thaliana contains eight genes encoding P(1B)-ATPases. The current reports show that the functions of P(1B)-ATPases are involved in maintaining metal homeostasis, transporting and detoxification in plants. P(1B)-ATPases not only mediated metal ion mobilization and uptake in roots, but also contribute to the metal transport, storage and tolerance in shoots, especially in heavy metal hyperaccumulators. In this paper, we reviewed and discussed the evolution, classification, structure and function of P(1B)-ATPases in plants. HMAs-transgenic manipulation could be a feasible approach for phytoremediation and mineral nutrition fortification.

Progress in the plant GH3 gene family / 生物工程学报

Phytohormone auxins play important roles in plant growth and development. The primary auxin-response genes can be classified into three major groups: Aux/IAAs, SAURs and GH3s. Significant progress has been made in understanding these gene families by approaches of the functional genomics, molecular genetics and molecular biology. In this review, we focused on the structures, functions and models of the expressional regulation of plant GH3 genes. The interactions in the signal transduction pathways between auxins and other signals mediated by the GH3 genes, the relationship between the GH3 genes and the stress adaptation responses of plants are emphasized.