Microbial production of medium-chain-length 3-hydroxyalkanoic acids by recombinant Pseudomonas putida KT2442 harboring genes fadL, fadD and phaZ.

Monomers of microbial polyhydroxyalkanoates, mainly 3-hydroxyhexanoic acid (3HHx) and 3-hydroxyoctanoic acid (3HO), were produced by overexpressing polyhydroxyalkanoates depolymerase gene phaZ, together with putative long-chain fatty acid transport protein fadL of Pseudomonas putida KT2442 and acyl-CoA synthetase (fadD) of Escherichia coli MG1655 in P. putida KT2442. FadL(Pp), which is responsible for free fatty acid transportation from the extracellular environment to the cytoplasm, and FadD(Ec), which activates fatty acid to acyl-CoA, jointly reinforce the fatty acid beta-oxidation pathway. Pseudomonas putida KT2442 (pYZPst01) harboring polyhydroxyalkanoates depolymerase gene phaZ of Pseudomonas stutzeri 1317 produced 1.37 g L(-1) extracellular 3HHx and 3HO in shake flask studies after 48 h in the presence of sodium octanoate as a sole carbon source, while P. putida KT2442 (pYZPst06) harboring phaZ(Pst), fadD(Ec) and fadL(Pp) achieved 2.32 g L(-1) extracellular 3HHx and 3HO monomer production under the same conditions. In a 48-h fed-batch fermentation process conducted in a 6-L fermentor with 3 L sodium octanoate mineral medium, 5.8 g L(-1) extracellular 3HHx and 3HO were obtained in the fermentation broth. This is the first time that medium-chain-length 3-hydroxyalkanoic acids (mcl-3HA) were produced using fadL(Pp) and fadD(Ec) genes combined with the polyhydroxyalkanoates depolymerase gene phaZ.

Comparison of classical diagnostic criteria and Chinese revised diagnostic criteria for fever of unknown origin in Chinese patients.

BACKGROUND: Fever of unknown origin (FUO) has always been a challenging problem for physicians since it was first reported half a century ago. This study aimed to investigate the clinical features of FUO and to compare the clinical significance of the classical diagnostic criteria and the Chinese revised diagnostic criteria of FUO. METHODS: We retrospectively collected a series of 140 patients admitted to our hospital between September 2011 and June 2013 because of prolonged febrile illnesses (lasting at least 2 weeks, temperature ≥38.5°C) without diagnosis and categorized them into two groups according to the Chinese revised diagnostic criteria (group A) and classical diagnostic criteria (group B) for FUO. The A group included patients presenting with fever persisting between 2 and 3 weeks with the diagnosis remaining uncertain after three outpatient visits or at least 3 days of hospital investigation. The B group included patients presenting with fever persisting for more than 3 weeks with no established diagnosis after 1 week of hospital investigation. The general conditions, etiologies, definite diagnosis times, and diagnostic methods of the two groups were compared. RESULTS: There were no significant differences in the general conditions, etiologies, definite diagnosis times, and diagnostic methods between the Chinese revised diagnostic criteria and classical diagnostic criteria. CONCLUSION: Both the examined FUO diagnostic criteria are suitable for clinical practice in this region.

Strategies for managing the insufficiency of the proximal landing zone during endovascular thoracic aortic repair.

BACKGROUND: The insufficiency of the proximal landing zone (PLZ) is a frequent factor challenging the applicability and efficacy of endovascular repair (EVR) for thoracic aortic disorders. This study discusses two strategies for conquering this challenge. METHODS: Ten patients underwent EVR for thoracic aortic diseases during a one-year period ending June 30, 2004. Nine patients had DeBakey type III dissecting aortic aneurysm (DAA), and one had descending thoracic aortic aneurysm (DTAA). The PLZ, defined as the distance from the origin of the left subclavian artery (LSA) to the primary entry tear of the dissection or to the proximal aspect of DTAA, was less than 15 mm in all instances. EVR with intentional coverage of the LSA without any supportive bypass was employed in 6 patients with DAA, and the preliminary right-left carotid and left carotid-subclavian bypass combined with EVR in the DTAA and other 3 DAA cases. RESULTS: Technical success was achieved in all the patients. The patient with DTAA died from hemispheric cerebral infarction and subsequent multiple system organ failure following an uneventful recovery from the cervical reconstruction performed 1 week previously. In cases receiving the EVR with intentional coverage of the LSA, in two patients dizziness occurred, which noticeably resolved after intravenous administration of mannitol for 4 to 5 days, and a drop in blood pressure of the left arm was noted in all the cases, but remained clinically silent. No neurological deficits or limb ischaemia developed perioperatively or during the followup, ranging from 3 to 12 months, and complete thrombosis of the thoracic aortic false lumen was revealed on CT at 3 months in the 9 patients with DAA. CONCLUSIONS: Both the intentional bypass absent coverage of the LSA and the adjunctive surgical bypass appear to be feasible and effective in managing the insufficiency of the PLZ during the endovascular thoracic aortic repair.

[Experimental study of Qiyeling Decoction inducing apoptosis of transplanted human lung adenocarcinoma cells A549 in nude mice].

OBJECTIVE: To study the function of Qiyeling Decoction in inducing apoptosis of transplanted human lung adenocarcinoma cells A549 in nude mice. METHODS: Nude mice with transplanted A549 tumor were randomly divided into the untreated control group (group A), chemotherapy treated group (group B), chemotherapy plus Qiyeling Decoction treated group (group C), Qiyeling Decoction treated group (group D) and managed correspondingly. The tumor volume was measured and calculated into tumor weight. The apoptosis of tumor cells were examined using in situ cell apoptosis detection kit. RESULTS: The tumor weight was lower obviously in groups B, C and D than that in group A (P<0.05). The apoptosis of tumor cells was lower obviously in groups B, and C than that in group D (P<0.05). Cells in group A appeared perfect differentiation during the early stage and apoptosis later. CONCLUSION: Qiyeling Decoction can induce A549 cell apoptosis in nude mice.