ABSTRACT
<p><b>OBJECTIVE</b>To review the application of thoracoscopic repair for treatment of congenital diaphragmatic hernia in neonates, so as to improve the cure rate.</p><p><b>METHODS</b>Clinical data of 47 neonates with congenital diaphragmatic hernia receiving thoracoscopic repair from June 2012 to June 2017 were reviewed. The admission age, gestational age, birth weight, timing of diagnosis, hernia location, clinical manifestation, surgical timing, surgical method, operation time, postoperative mechanical ventilation time of patients were analyzed.</p><p><b>RESULTS</b>There were 42 cases of left diaphragmatic hernia and 5 cases of right diaphragmatic hernia. Thirteen cases were diagnosed prenatally. Primary diaphragmatic repair was successfully accomplished under thoracoscope in 45 neonates without perioperative complications, while 2 patients were converted to open surgery. The average operation time was (63±13) min (42-150 min), the average blood loss was (3.0±1.7) mL (1.0-9.0 mL), and the average postoperative mechanical ventilation time was (3.9±1.4) d (2.0-11.0 d). Two patients died and the treatment was withdrawn in 3 patients with an overall cure rate of 89.4% (42/47).</p><p><b>CONCLUSIONS</b>Thoracoscopic repair is effective and can be used as first-choice treatment of diaphragmatic hernia in neonates.</p>
ABSTRACT
It is very important to obtain high yield mutant strains on the base of metabolic flux analysis of Actinobacillus succinogenes S.JST for the industrial bioconversion of succinic acid. The metabolic pathway was analized at first and the flux of the metabolic networks was calculated by matrix. In order to decrease acetic acid flux, the strains mutated by soft X-ray of synchronous radiation were screened on the plates with high concentration of fluoroacetic acid. For decreasing the metabolic flux of ethanol the site-directed mutagenesis was carried out for the reduction of alcohol dehydrogenase(Adh) specific activity. Then the enzyme activity determination and the gene sequence analysis of the mutant strain was compared with those of the parent strain. Metabolic flux analysis of the parent strain indicated that the flux of succinic acid was 1.78(mmol/g/h) and that the flux of acetic acid and ethanol were 0.60 (mmol/g/h) and 1.04( mmol/g/h), respectively. Meanwhile the metabolic pathway analysis showed that the ethanol metabolism enhanced the lacking of H electron donor during the synthesis of succinic acid and that the succinic acid flux was weakened by the metabolism of byproducts ethanol and acetic acid. Compared with the parent strain, the acetic acid flux of anti-fluoroacetic mutant strain S.JST1 was 0.024 (mmol/g/h), decreasing by 96%. Then the enzyme determination showed that the specific activity unit of phosphotransacetylase(Pta) decreased from 602 to 74 and a mutated site was founded in the pta gene of the mutant strain S.JST1. Compared with that of the parent strain S.JST1 the ethanol flux of adh-site-directed mutant strain S.JST2 was 0.020 (mmol/g/h), decreasing by 98%. Then the enzyme determination showed that the specific activity unit of Adh decreased from 585 to 62 and the yield of end product succinic acid was 65.7 (g/L). The interdiction of Adh and Pta decreased the metabolism of byproducts and the H electron donor was well balanced, thus the succinic acid flux was strengthened by the redundant carbon flux from these byproducts. The mutant strain S.JST2 obtained in this paper deserves being extended to application of industrial fermentation.