Methane monooxygenases (MMO), regarded as "an amazing biomolecular machine", catalyze the oxidation of methane to methanol under aerobic conditions. MMO catalyze the oxidation of methane elaborately, which is a novel way to catalyze methane to methanol. Furthermore, MMO can inspire the biomolecular machine design. In this review, we introduced MMO including structure, gene and catalytic mechanism. The history and the taxonomy of MMO were also introduced.
Catalysis ; Methane ; metabolism ; Methanol ; metabolism ; Oxygenases ; metabolism

Objective To investigate the effect of 12-lipoxygenase(12-LOX) inhibitor inducing the apoptosis of human hepatocellular carcinoma cell line HepG2 on the expression of survivin gene.Methods HepG2 cells were cultivated in RPMI-1640 medium.12-LOX mRNA was analyzed by reverse transcription polymerase chain reaction(RT-PCR).The effect of baicalein on the proliferation of the cells was detected by thiazolyl blue tetrazoliumbromide(MTT) method.The subcellular structures were observed under electron microscope.DNA ladder pattern on agarose gel electrophores was used to evaluate the apoptotic index of hepG2 cells.The expression of survivin mRNA was analyzed by RT-PCR.Results 12-LOX mRNA was expressed in human HepG2 cells.At concentrations from 20 to 80 ?mol?L-1,baicalein inhibited the proliferation of HepG2 cells in a concentration-and time-dependent manner from 24 to 72 h.There were significant differences between any other groups(P

Objective To observe the effect of postoperative central vault on the anterior chamber after implantation of im-plantable contact lens V4c .Methods To carry out a retrospective study of 56 eyes with implantable contact lens V4c implantation in Chongqing Bright Eye Hospital from November 2 ,2014 to February 5 ,2015 ,examined anterior chamber angle before surgery ,the anterior chamber angular width (ACA) and anterior chamber volume (ACV) were measured by pentacam .the postoperative central vault and ACA and ACV during the first and third and sixth months after surgery were measured ,the pigment grade in anterior chamber after operation were recorded .The change of ACA and ACV of the 56 eyes was correlation analyzed .Results At first month after surgery ,the postoperative central vault was 250 ~ 765 μm ,the reduced amount of ACA was (13 .67 ± 1 .67)° ,the re-duced amount of ACV was (94 .23 ± 17 .02)mm3 .At the third month ,the postoperative central vault of the 55 eyes was 239 ~ 761μm ,the reduced amount of ACA was (13 .70 ± 1 .68)° ,The reduced amount of ACV was (93 .6 ± 17 .48)mm3 .At the sixth month , the postoperative central vault of the 51 eyes was 246 ~ 761 μm ,the reduced amount of ACA was (13 .60 ± 1 .69)° ,the reduced a-mount of ACV was(94 .29 ± 17 .80)mm3 .No case of pigment was found for grade Ⅱ .The statistical comparison of the amount of ACV and ACA decreased in different postoperative central vaults showed that the difference was statistically significant ,there were statistically significant differences in the amount of ACV and ACA between different central postoperative central vault(P< 0 .05) . Conclusion Anterior chamber angle was narrowed and anterior chamber volume decreased in the posterior chamber intraocular lensimplant-ation after implantable contact lens V4c implantation ,the postoperative central vault is related to the change of anterior chamber angle and ACV .Appropriate postoperative central vault has positive clinical significance for keeping anterior chamber angle open .

Objective To analyze the influence of dexamethasone in the hypotonic-induced volume-sensitive chloride currents in human trabecular meshwork cells,and to investigate the possible mechanism of volume-sensitive chloride channels(VACC)in the glucocorticoid-induced glaucoma(GIG)cases.Methods The human trabecular meshwork cells were seeded in 35 mm diameter plastic petri dishes,so that they could grow in monolayer.The cultured cells were divided into normal cell culture medium group and dexamethasone 1 d,3 d,7 d groups.The chlorine current density values of the cells in four groups were recorded respectively by the whole-cell patch-clamp technique. The differences among groups were compared.Results In normal group,after hypotonic stimulation,under+100 and-100 mV voltage clamp,the outward and inward current density values of the trabecular cells were (19.94±0.87) and (-6.53±0.41)pA/pF.In dexamethasone 1 d,3 d,and 7 d groups,under the same condition,the outward and inward current density values of the trabecular cells were (19.39 ± 1.40)and (-6.42 ± 0.28)pA/pF, (17.97±2.35)and (-5.82±0.94)pA/pF,(17.16±1.16)and (-5.65±0.43)pA/pF.The trabecular cells cultured with dexamethasone for 1 d had lower outward and inward current density values under hypotonic stimulation compared with normal group,but there was no significant difference (P>0.05).The trabecular cells cultured with dexamethasone for 3 d and 7 d,when compared with normal group,had significantly lower outward and inward current density values under hypotonic stimulation (P<0.05 ). Conclusion Dexamethasone could reduce the volume-sensitive chloride current in trabecular meshwork cells,which would affect trabecular meshwork cell volume adjustment.This would possibly cause the increase of the aqueous humor outflow resistance among GIG cases.

Objective To observe the changes in contrast sensitivity(CS) and color vision in patients with primary acute angle-closure glaucoma(PACG).Methods CS and color vision tests were performed in 35 patients(35 eyes) with preclinical stage of PACG,32 patients(32 eyes) with acute attack stage of PACG and 15 normal subjects(30 eyes).Then patients were followed up 1 month(31 eyes) and 3 months(28 eyes) after operation.Results The results of CS and color vision tests were abnormal in PACG patients when they were compared with those of normal people.The threshold of CS at 18.0 c/d was increased(P

OBJECTIVE To introduce a new type of tracheal cannula which has the top hole and can seal the outlet for patient with severe brain injury after tracheotomy. METHODS Patients with severe brain injury after tracheotomy were divided into test group using the new type of tracheal cannula(25 cases) and control group using the cuffed Portex tube(25 cases).The incidence,the onset time and the time for control of pulmonary infection were compared between the two groups. RESULTS In the test group,the incidence of pulmonary infection was 52%(13 cases),the onset time was(3?1.3) days and the time for control was(5?1.7) days;in the control group,the above indices were 84%(21 cases),(3?1.5) days and(12?2.2) days separately. CONCLUSIONS The new type of tracheal cannula which has the top hole and can seal the outlrt is better than the cuffed Portex tube in the prevention and treatment of pulmonary infection after tracheotomy.

Objective To investigate the clinical value of transumbilical endoscopic thoracic sympathectomy on women patients with palmar hyperhidrosis.Methods A total of 25 consecutive women patients with palmar hyperhidrosis underwent transumblical thoracic sympathectomy with ultra-thin endoscope.The operative data,including duration of operation,intra-operative and postoperative complications were recorded.Results The procedure was performed successfully in all 25 patients with a mean operative time of 64 min(58-113 min).No umbilical hernia,diaphragmatic hernia,Horner's syndrome or hemothorax were observed.Minor pneumothorax was found in postoperative chest X-ray in 3 patients,all of which were completely resolved with conservative treatment.All patients recovered to their normal life at 1 week after discharge.The scar was small and hidden in umbilical with no visible incisions.After a follow-up of 4 to 12 months,all patients' hands sweating symptoms completely disappeared,axillary sweat symptoms completely resolved in 6 patients,significantly improved in 4 and mildly improved in 1.Conclusion Transumbilical thoracic sympathectomy with ultrathin flexible endoscope is a safe and effective option for women patients with severe palmar hyperhidrosis,which provides excellent cosmetic outcomes.

Objective To study the effect of muskmelon juice on immune function of aged mice induced by D-galactose. Method Fifty male Kunming mice were randomly divided into five groups:normal control,aged model and three muskmelon juice (quadruple-diluted,double-diluted and stock juice) groups. The mice in aged model and three muskmelon juice groups were injected subcutaneously with D-galactose at dose of 200 mg/kg?d ,and the normal control with the normal saline of equal volume. The mice in three muskmelon juice groups were treated by intragastric administration twice daily with quadruple-diluted solution,double-diluted solution and stock liquid of muskmelon juice respectively,and the mice in normal control and aged model group with distilled water. Four weeks later,spleen and thymus were weighted,and the immunoglobulim and complement in serum were estimated. Results The thymus index of mice in aged model groop was much lower as compared with normal control. After administration with muskmelon juice,the thymus index was increased and the difference between stock juice and aged model group was significant. As compared with normal control,the serum IgG,IgM,C3,C4 contents of aged model were significantly lowered,but those in muskmelon juice group was increased. The IgG,C3,C4 contents of double-diluted and stock juice group were significantly higher than those of aged model. The spleen index and serum IgA contents fluctuated with same tendency. Conclusion Muskmelon juice can relieve the regression of immune organs in aging process and improve the immune function,suggesting to be effective in anti-aging process.

Objective:To investigate the azole susceptibility of Candida albicans (C. albicans) from vulvovaginal candidosis patients and to analyze the relationship between ERG11 gene mutations in these isolates and azole resistance.
Methods:Three hundred and two clinical isolates of Candida species were collected. Azole susceptibility was tested in vitro in microdilution studies. The ERG11 genes of 17 isolates of C. albicans (2 susceptibles, 5 dose-dependent resistants and 10 resistants) were amplified and sequenced.
Results:Of the 302 isolates collected, 70.2%were C. albicans, of which 8.5%, 3.8%and 4.2%were resistant to fluconazole, itraconazole and voriconazole, respectively. In total, 27 missense mutations were detected in ERG11 genes from resistant/susceptible dose-dependent isolates. Among them, Y132H, A114S, and Y257H substitutions were most prevalent and were known to cause fluconazole resistance. G464S and F72S also has been proved to cause fluconazole resistance. Two novel substitutions (T285A, S457P) in hotspot regions were identified.
Conclusions:Twenty seven mutations in the ERG11 gene were identified in azole-resistant C. albicans isolates, which indicated a possible relation with the increase in resistance to azole drugs and the recurrence of vulvovaginal candidosis. The relationship of two novel substitutions (T285A, S457P) with fluconazole resistance needs to be further verified by site-directed mutagenesis.

Objective: To understand the occurrence and predictive factors of depressive symptoms among multi ethnic middle school students in Yunnan Province, so as to provide a referential framework for schools to carry out targeted mental health education. Methods: From October to December 2022, 8 500 first grade students from 23 middle schools were selected from 11 minority areas in Yunnan Province by cluster random sampling method. Demographic information and data relating to the students lifestyles were collected by questionnaire, and the Children s Depression Inventory (CDI) was used to evaluate depressive symptoms. Chi square test was performed to compare differences in the detection rate of depressive symptoms among first grade middle school students for univariate analysis. A decision tree model of depressive symptoms in middle school students was established by using the Chi squared automatic interaction detector (CHAID). Results: The detection rate of depressive symptoms among first grade students from multi ethnic middle schools in Yunnan Province was 28.26%. The decision tree model of depressive symptoms was academic stress ( χ 2=469.08) at the first level, breakfast behaviors (low/moderate academic stress: χ 2=155.49; severe academic stress: χ 2=105.24) at the second level, and the number of close friends (low/moderate academic stress and consuming breakfast 0- 2 days weekly: χ 2=23.15; low/moderate academic stress and consuming breakfast 3-4 days weekly: χ 2=14.99; severe academic stress and consuming breakfast 0-2 days weekly: χ 2=29.26; severe academic stress and consuming breakfast 3-4 days weekly: χ 2=20.15), ethnicity ( χ 2=78.22) and drinking ( χ 2=50.36) at the third level ( P <0.01). Conclusions The study identifies academic stress, breakfast behaviors, number of close friends, drinking and ethnicity as predictive factors of depressive symptoms among multi ethnic middle school students in Yunnan Province. Schools should develop targeted strategies for preventing and managing depressive symptoms in middle school students, so as to reduce their occurrence.