Microbial etiology, susceptibility profile of postradiation nasopharyngeal necrosis patients with nasopharyngeal carcinoma.

OBJECTIVE: Postradiation nasopharyngeal necrosis (PRNN) is a notorious complication after radiotherapy that affects prognosis in patients with nasopharyngeal carcinoma (NPC). It is important for clinical doctors to realize this problem in order to cope with this severe clinical situation. The aim of our study was to assess the bacteriology of PRNN and to demonstrate the antimicrobial susceptibility pattern that should guide the clinicians towards more appropriate antibiotic use. METHODS: Sixty-nine NPC patients with PRNN in our department between March 2013 and December 2017 were retrospectively enrolled. Pathogenic culture and drug sensitivity test were performed in these 69 NPC patients with PRNN. The infection rate of Pathogens and the sensitivity of the drugs were analyzed based on these results. RESULTS: Sixty-nine NPC patients with PRNN were enrolled in our study. Pathogens were identified in 58 (84%) patients. Of the 58 patients, Staphylococcus aureus was isolated in 34 (58.6%) patients. And the second most common group of bacterial isolates was Pseudomonas aeruginosa. Antibiotic sensitivity showed that Levofloxacin was the highest (88.5%), followed by Ciprofloxacin (85.2%) and Gentamicin (80.3%). The only pathologic fungus was Candidaalbicans, about 6.8%. The positive rates of bacterial and fungal culture in PRNN patients were not significantly different from the patients' gender, age, stage, number of radiotherapy courses (P>0.05), but the cure rate was statistically higher in culture-negative patients in comparison with culture-positive patients (63.6% vs 20.7%, P=0.011). CONCLUSION: Our results provide an overall picture of the microbiology and drug susceptibility patterns for NPC patients with PRNN and could help implement guidelines for more rational treatment and improve therapeutic outcome.

Three new cassane diterpenes from the seeds of Caesalpinia minax Hance.

Four fractions were prepared from the crude extract of Caesalpinia minax Hance and the inhibitory activity of nitric oxide (NO) production release of RAW 264.7 cells stimulated by lipopolysaccharide (LPS) was evaluated. The ethyl acetate (EtOAc) fraction showed obvious inhibitory effect. Bioassay-guided fractionation led to the isolation of three new cassane diterpenes, caesalmin X (1), caesalmin Y (2) and caesalmin Z (3), together with 19 known cassane diterpenoids (4-22). Their structures were mainly characterised on the basis of extensive spectroscopic analyses and comparison with reported data. Moreover, three compounds (20-22) which possessed furanditerpenoid 7,17-lactone structures, displayed moderate activities, with IC50 value of 29.85, 27.38 and 25.40 µM, respectively.

Solanerioside A, an unusual 14,15-dinor-cyclophytane glucoside from the leaves of Solanum erianthum.

Solanerioside A (1), the first example of a diterpenoid glucoside featuring a 14,15-dinor-cyclophytane scaffold, together with three known terpene glucosides (2-4) were isolated from the methanol extract of the leaves of Solanum erianthum (Solanaceae). The structure of 1 was mainly characterised on the basis of extensive spectroscopic analyses, especially from the 2D NMR spectra. In addition, the spectroscopic data of (6E, 10E)-5,12-dihydroxy-ß-nerolidol 5-O-ß-D-glucopyranoside (3) were reported for the first time. However, these compounds did not display obvious inhibition of LPS-induced NO release in RAW264.7 cells and anti-tumour activity against A549, HepG2, Hela and MCF-7 cells in vitro.

Enantiomeric Neolignans and a Sesquiterpene from Solanum erianthum and Their Absolute Configuration Assignment.

One pair of new C-8-C-3'/C-7-O-C-4' linked neolignan enantiomers (1a/1b) and one new guaiane sesquiterpene (2) first featuring the 1(2),9(10)-conjugated double bond were isolated from the stems of Solanum erianthum (Solanceae). Their structures were characterized on the basis of extensive spectroscopic analyses, especially from their 2D nuclear magnetic resonance (NMR) spectra. The absolute configurations of 1a/2b were rigorously elucidated by electronic circular dichroism (ECD) experiments combined with the reversed helicity rule for the 2,3-dihydrobenzo[b]furan chromophore, and compound 2 is the first report on the sterochemical assignment of a guaiane sesquiterpene by using the allylic axial chirality rule for the conjugated diene chromophore in combination with the calculated ECD spectrum.