Chemical composition, antimicrobial and larvicidal activities of essential oils of two Syzygium species from Vietnam.

The present study is the first to investigate the chemical composition, antimicrobial and larvicidal activities of the essential oils from the leaves of Syzygium attopeuense (Gagnep.) Merr. & L.M.Perry and Syzygium tonkinense (Gagnep.) Merr. & L.M.Perry collected in Vietnam. The essential oils were extracted by hydrodistillation and analyzed by GC and GC-MS. The study indicated the presence of a high percentage of sesquiterpenes in both investigated essential oils. The major components of S. attopeuense essential oil were bicyclogermacrene (24.26%), (E)-caryophyllene (11.72%), and (E)-ß-ocimene (6.75%), whereas S. tonkinense essential oil was dominated by (E)-caryophyllene (80.80%). The antimicrobial activity of essential oils was evaluated by broth microdilution assay to determine the minimum inhibitory concentration (MIC) and median inhibitory concentration (IC50). Both essential oils exhibited remarkable inhibitory activity against all tested Gram-positive bacteria and yeast than Gram-negative bacteria. Among them, essential oils of S. attopeuense and S. tonkinense possessed the strongest activity against Enterococcus faecalis (MIC = 4.00 µg/mL; IC50 = 1.69 µg/mL) and Candida albicans (MIC = 16.00 µg/mL; IC50 = 8.67 µg/mL), respectively. Furthermore, the larvicidal activity of essential oils was tested using fourth-instar larvae of Aedes aegypti. Results from the larvicidal test revealed that both essential oils had an excellent inhibitory effect against A. aegypti larvae with LC50 values from 25.55 to 30.18 µg/mL and LC90 values from 33.00 to 39.01 µg/mL. Our findings demonstrate that the essential oil extracted from S. attopeuense and S. tonkinense are potential sources of natural antimicrobials and can act as inexpensive mosquito larvicidal agents.

[Cyclopexy on cyclodialysis cleft guided by anterior segment optic coherence tomography].

Objective: To analyze the accuracy of cyclopexy on traumatic cyclodialysis cleft guided by anterior segment optic coherence tomography (AS-OCT). Methods: Fifty-six eyes of 56 consecutive patients[41 males, 15 females, with a mean age of (43.14±13.85) years]who diagnosed with traumatic cyclodialysis cleft confirmed by ultrasound biomicroscopy (UBM) and underwent cyclopexy surgery at Shanxi Eye Hosiptal from July 2013 to February 2016 were included in the study. Patients were measured with the AS-OCT system before cyclopexy. AS-OCT findings of the cyclodialysis clefts were recorded. Localizing and suturing the clefts was guided by AS-OCT imaging. Preoperative and postoperative visual acuity (VA), intraocular pressure (IOP) and anterior chamber depth (ACD) were recorded and analyzed. Results: Imaging of preoperative AS-OCT of the 56 eyes showed an annular ciliary body detachment, a cyclodialysis cleft and shallow anterior chamber. The ciliary body detachment detected by AS-OCT showed an echo free zone between the annular ciliary body and the sclera. The cyclodialysis cleft showed a new pathway between the anterior chamber and the suprachoroidal space. AS-OCT imaging showed that the extent of cyclodialysis clefts ranged from 30 degrees to 240 degrees, which had a 0 degree to 20 degrees difference compared with UBM imaging. Localizing and suturing of the cyclodialysis clefts was guided by AS-OCT imaging. The best corrected visual acuity (BCVA) was 0.21±0.17 at baseline and 0.29±0.21 at five days postoperatively. The initial and final BCVA showed a remarkable difference after treatment (t=-4.98, P<0.01). The mean intra-ocular pressure (IOP) was (8.33±2.29) mmHg before surgery and (15.40±2.34) mmHg at five days postoperatively. There was a significant difference of IOP between preoperative and postoperative period (t=-16.590, P<0.01). The mean ACD was (1.94±0.45) mm preoperatively and (2.69±0.44) mm at five days postoperatively. There was also a significant difference of ACD between preoperative and postoperative period (t=-10.276, P<0.01). The postoperative reexamination found that ciliary body detachment or cyclodialysis clefts was not observed in the 56 eyes by AS-OCT. Conclusions: As a non-invasive method, AS-OCT is accurate, correlating well with UBM in the examination of cyclodialysis cleft, and can localize the extent of clefts before cyclopexy.

Study on the volatile oil contents of Annona glabra L., Annona squamosa L., Annona muricata L. and Annona reticulata L., from Vietnam.

The volatile compounds identified from four species of Annona from Vietnam are being reported. The oils were obtained from aliquots of plant samples by steam distillation and subjected to GC and GC-MS analysis. The main compounds of Annona glabra L., were ß-caryophyllene (21.5%) germacrene D (17.7%), α-cadinol (5.4%) and ß-elemene (5.2%). Annona squamosa L., comprised mainly of α-pinene (1.0-11.9%), limonene (0.8-11.7%), ß-cubebene (0.5-13.0%), ß-caryophyllene (11.6-24.5%), spathulenol (0.8-9.0%), caryophyllene oxide (1.0-10.6%) and α-cadinol (3.3-7.8%). The significant constituents of Annona muricata L., were α-pinene (9.4%), ß-pinene (20.6%), ρ-mentha-2,4(8)-diene (9.8%), ß-elemene (9.1%) and germacrene D (18.1%). However, camphene (0.2-6.6%), α-copaene (2.0-7.3%), ß-elemene (5.9-16.6%), ß-caryophyllene (8.3-14.9%), ß-bisabolene (0.4-10.2%), δ-cadinene (1.7-4.8%) and germacrene D (9.3-22.8%) were the main compounds common to samples of Annona reticulata L. There were significant amounts of sabinene (11.2% and 2.7%; leaf and stem bark) and bicycloelemene (9.6% and 6.1%; stem and bark).

Dissociation and association rate constants changes following bilirubin binding affinity decreases.

The effect of sulfisoxazole, sodium salicylate, sodium cholate, urea and dimethyl sulfoxide on the kinetics of the bilirubin to human serum albumin at 24 degrees C and pH 7.40 was investigated. A marked decrease of the association constant was obtained. It was due mainly to that of the association rate constant, and might be an additional risk factor to the icteric newborn: when blood bilirubin increases, unbound bilirubin which cannot rapidly associate to albumin may reach a dangerous level, even when its equilibrium concentration is low.