ABSTRACT
Seventy two patients with initial cerebral infarction admitted in the Second Hospital of Jiaxing from March 2017 to October 2017 were enrolled. Patients underwent conventional ultrasonography and contrast-enhanced ultrasonography for two-dimensional echo grading and neovascularization grading of carotid artery plaques respectively. There were 113 carotid plaques in 72 patients with cerebral infarction,27 cases recurred after 1 years with 44 patches. The echo grading of recurrence group was mainly grade Ⅰ and grade Ⅱ,the number of Ⅰ,Ⅱ,and Ⅲ plaques was 23,18,and 3,respectively. The echo grading of non-recurrence group was mainly grade Ⅲ,the number of Ⅰ,Ⅱ,and Ⅲ plaques was 36,23,and 40,respectively. The echo grading of carotid artery plaque between the two groups was significantly different (P<0.05). The grade of carotid neovascularization in recurrence group was mainly grade Ⅲ and grade Ⅳ,the number of Ⅰ,Ⅱ,Ⅲ and Ⅳ plaques was 2,5,27 and 10,respectively. The echo grading of non-recurrence group was mainly grade Ⅰ and grade Ⅱ,the number of Ⅰ,Ⅱ,Ⅲ and Ⅳ plaques was 24,52,14 and 9,respectively. There was significant difference in the grade of carotid neovascularization between the two groups (P<0.05). The area under curve(AUC) of echo grade<Ⅱ,echo grade<Ⅲ,neovascularization grade>Ⅰ,neovascularization grade>Ⅱ and neovascularization grade>Ⅲ in predicting the recurrence of cerebral infarction were 0.553,0.641,0.587,0.793 and 0.557,respectively,the AUC of neovascularization grade>Ⅱ was significantly higher than the other four criteria (P<0.01). The recurrence curves of carotid plaques with different neovascularization grades were significantly different (χ2=49.18,P<0.01). Carotid plaque vulnerability evaluated by contrast-enhanced ultrasonography is an effective indicator for predicting recurrence of cerebral infarction.
ABSTRACT
Gene deletion vector pLJ04(pKC1139∷bkdF+bkdH)was used to disrupt bkdFGH in Streptomyces avermitilis 76-02-e,an industrial producer of anthelmintic avermectin.The disruptants were confirmed by PCR.Shake flask experiment and HPLC analysis showed that the mutant lost the ability to produce avermectins.As it is expected,the mutant,named S.avermitilis bkd76-3,could restore the ability of producing avermectins when the feeding of methylbutyric acid and isobutyric acid to its fermentations was carried out.The addition of cyclohexanecarboxylic acid(CHC)into fermentations of the S.avermitilis bkd76-3 allowed for production of four components,two of which was confirmed as CHC-B1 and CHC-A2 by LC/MS analysis,respectively.