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1.
Macromol Rapid Commun ; 43(5): e2100736, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34837422

RESUMEN

Nano- and microscale morphology endows surfaces that play conspicuous roles in natural or artificial objects with unique functions. Surfaces with dynamic regulating features capable of switching the structures, patterns, and even dimensions of their surface profiles can control friction and wettability, thus having potential applications in antibacterial, haptics, and fluid dynamics. Here, a freestanding film with light-switchable surface based on cholesteric liquid crystal networks is presented to translate 2D flat plane into a 3D nanometer-scale topography. The wettability of the interface can be controlled by hiding or revealing the geometrical features of the surfaces with light. This reversible dynamic actuation is obtained through the order parameter change of the periodic cholesteric organization under a photoalignment procedure and lithography-free mode. Complex tailored structures can be used to encrypt tactile information and improve wettability by predesigning the orientation distribution of liquid crystal director. This rapid switching nanoprecision smart surface provides a novel platform for artificial skin, optics, and functional coatings.


Asunto(s)
Cristales Líquidos , Cristales Líquidos/química , Humectabilidad
2.
ACS Appl Mater Interfaces ; 13(46): 55550-55558, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34761914

RESUMEN

Dynamic control of motion at the molecular level is a core issue in promoting the bottom-up programmable modulation of sophisticated self-organized superstructures. Self-assembled artificial nanoarchitectures through subtle noncovalent interactions are indispensable for diverse applications. Here, the active solar renewable energy is used to harness cholesteric liquid crystal (CLC) superstructure devices via delicate control of the dynamic equilibrium between the concentrations of molecular motor molecules with opposite handedness. Thus, the spectral position and handedness of a photonic superstructure can be tuned continuously, bidirectionally, and reversibly within the entire working spectrum (from near-ultraviolet to the thermal infrared region, over 2 µm). With these unique horizons, three advanced photoresponsive chiroptical devices, namely, a mirrorless laser, an optical vortex generator, and an encrypted contactless photorewritable board, are successfully demonstrated. The sunlight-fueled chirality inversion prompts facile switching of functionalities, such as free-space optical communication, stereoscopic display technology, and spin-to-orbital angular momentum conversion. Motor-based chiroptic devices with dynamic and versatility controllability, fast response, ecofriendly characteristics, stability, and high efficiency have potential to replace the traditional elements with static functions. The inexhaustible natural power provides a promising means for outdoor-use optics and nanophotonics.

3.
Artículo en Inglés | MEDLINE | ID: mdl-30105065

RESUMEN

Although acupuncture is considered to be effective and safe for Alzheimer's disease (AD) and mild cognitive impairment (MCI), the mechanism underlying its therapeutic effect is still unknown. Most studies clarifying the neuronal pathway produced by acupuncture were still applied to healthy subjects with limited single acupuncture point stimulation, which was inconsistency with clinical practice. Thus, in our present study, we investigate the differences between brain activity changes in AD and MCI patients caused by multi-acupuncture point Siguan (four gates), in order to provide visualized evidence for neuronal specificity of clinical acupuncture. Forty-nine subjects were recruited, including 21 AD patients, 14 MCI patients, and 14 healthy controls (HC). AD and MCI patients were randomly divided into two groups, respectively: real acupuncture point group (14 AD and 8 MCI) and sham acupuncture point group (7 AD and 6 MCI). We adopted a 16-minute, single-block, experimental design for acquiring functional MRI images. We found, in AD and MCI patients, Siguan (four gates) elicited extensive activations and deactivations in cognitive-related areas, visual-related areas, the sensorimotor-related area, basal ganglia, and cerebellum. Compared with HC, AD and MCI patients showed similar activations in cognitive-related brain areas (inferior frontal gyrus, supramarginal gyrus, and rolandic operculum) as well as deactivations in cognitive-related areas, visual-related areas, basal ganglia, and cerebellum, which were not found in HC. Compared with sham acupuncture points, real acupuncture points produced more specific brain changes with both activated and deactivated brain activities in AD and MCI. The preliminary results in our study verified the objective evidence for neuronal specificity of acupuncture in AD and MCI patients.

4.
Artículo en Inglés | MEDLINE | ID: mdl-25525442

RESUMEN

Clarifying the intrinsic mechanisms of acupuncture's clinical effects has recently been gaining popularity. Here, we choose the Siguan acupoint (a combination of bilateral LI4 and Liv3) and its sham point to evaluate multiacupoint specificity. Thirty-one healthy volunteers were randomly divided into real acupoint (21 subjects) and sham acupoint (10 subjects) groups. Our study used a single block experimental design to avoid the influence of posteffects. Functional magnetic resonance imaging data were acquired during acupuncture stimulation. Results showed extensive increase in neuronal activities with Siguan acupuncture and significant differences between stimulation at real and sham points. Brain regions that were activated more by real acupuncture stimulation than by sham point acupuncture included somatosensory cortex (the superior parietal lobule and postcentral gyrus), limbic-paralimbic system (the calcarine gyrus, precuneus, cingulate cortex, and parahippocampal gyrus), visual-related cortex (the fusiform and occipital gyri), basal ganglia, and the cerebellum. In this way, our study suggests Siguan may elicit specific activities in human brain.

5.
Int J Mol Sci ; 15(12): 21992-2010, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25470020

RESUMEN

Monoterpenoids are a diverse class of natural products and contribute to the important varietal aroma of certain Vitis vinifera grape cultivars. Among the typical monoterpenoids, linalool exists in almost all grape varieties. A gene coding for a nerolidol/linalool (NES/LINS) synthase was evaluated in the role of linalool biosynthesis in grape berries. Enzyme activity assay of this recombinant protein revealed that it could convert geranyl diphosphate and farnesyl diphosphate into linalool and nerolidol in vitro, respectively, and thus it was named VvRILinNer. However, localization experiment showed that this enzyme was only localized to chloroplasts, which indicates that VvRILinNer functions in the linalool production in vivo. The patterns of gene expression and linalool accumulation were analyzed in the berries of three grape cultivars ("Riesling", "Cabernet Sauvignon", "Gewurztraminer") with significantly different levels of monoterpenoids. The VvRILinNer was considered to be mainly responsible for the synthesis of linalool at the early developmental stage. This finding has provided us with new knowledge to uncover the complex monoterpene biosynthesis in grapes.


Asunto(s)
Frutas/enzimología , Hidroliasas/metabolismo , Monoterpenos/metabolismo , Plastidios/enzimología , Sesquiterpenos/metabolismo , Vitis/enzimología , Vitis/crecimiento & desarrollo , Monoterpenos Acíclicos , Secuencia de Aminoácidos , Electroforesis en Gel de Poliacrilamida , Frutas/genética , Frutas/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Proteínas Fluorescentes Verdes/metabolismo , Hidroliasas/química , Hidroliasas/genética , Anotación de Secuencia Molecular , Datos de Secuencia Molecular , Filogenia , Proteínas Recombinantes/aislamiento & purificación , Alineación de Secuencia , Fracciones Subcelulares/enzimología , Vitis/genética
6.
Zhonghua Yan Ke Za Zhi ; 49(4): 345-9, 2013 Apr.
Artículo en Chino | MEDLINE | ID: mdl-23900095

RESUMEN

OBJECTIVE: To analyze the distribution and shifting trends of fungal culture specimens and assess the drug sensitivity in vitro. METHODS: Case series study. From January 2009 to December 2010, 1302 specimens were collected. These specimens were cultured on potato dextrose agar medium under 28°C and 40% humidity for 3 - 8 days. Drug sensitivity of positive cultures were evaluated by K-B method. Chi-square test was used for the analysis. RESULTS: In 1302 specimens, 292 samples (22.4%) were culture-positive, in which 69.9% were isolated from the cornea, 3.8% from the vitreous body, 1.0% from the anterior chamber, 0.7% from the conjunctiva, 0.7% from palpebral margin and 24.0% from other parts of the eye. Culture-positive rate of 2009 and 2010 were 21.2% (135/637) and 23.6% (157/665) respectively with no statistically significant difference (χ(2) = 1.092, P = 0.296). Two peaks of culture-positive outcome appeared in May and November. Culture results showed that Fusarium sp. was the commonest pathogen (59.6%, 174/292), Aspergrium sp. in 16.8% (49/292) and Alternaria sp.in 10.6% (31/292). Patients from 31 to 60 years old accounted for 82.2% (240/292) of positive cases. The sensitive rate in vitro to natamycin, terbinafine, fluconazole, amphotericin B and itraconazole was 94.0% (63/67), 63.4% (154/ 243), 6.0% (17/285), 39.7% (98/247) and 21.2% (65/306), respectively. CONCLUSIONS: The top three commonest fungus of Beijing Tong Ren hospital successively are Fusarium sp., Aspergrium sp. and Alternaria sp. Natamycin should be the first choice for fusarium infection and pathogen-unknown infection. All species with the exception of Fusarium sp. are sensitive to natamycin, terbinafine and amphotericin B but not itraconazole. Almost all fungal strains are resistant to fluconazole.


Asunto(s)
Antifúngicos/farmacología , Infecciones Fúngicas del Ojo/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alternaria/efectos de los fármacos , Alternaria/aislamiento & purificación , Aspergillus/efectos de los fármacos , Aspergillus/aislamiento & purificación , Niño , Preescolar , Farmacorresistencia Fúngica , Infecciones Fúngicas del Ojo/epidemiología , Femenino , Fusarium/efectos de los fármacos , Fusarium/aislamiento & purificación , Humanos , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
7.
Zhonghua Yan Ke Za Zhi ; 49(1): 8-11, 2013 Jan.
Artículo en Chino | MEDLINE | ID: mdl-23601458

RESUMEN

OBJECTIVE: To investigate the cytological feature and differentiate diagnosis of ocular fungal infections by smear cytology. METHODS: Experimental study. One thousand two hundred and twenty-six specimens of smear cytology were collected retrospectively during January 2007- December 2010 from Microbial Laboratory of Beijing Institute of Ophthalmology. The 1226 specimens analyzed in this study were collected from patients who suffered from ocular fungal infections. The corneal scraping cells were observed by Giemsa staining, and the photographic record was saved. The morphological characteristics of fungal pathogens and the surrounding cells were analyzed by light microscopy. RESULTS: Nine hundred and ninety eight of 1226 (81.40%) specimens were positive with fungal pathogens, 228 of 1226 (18.60%) specimens were fungal negative by smear cytology. 976 of 998 (97.80%) fungal positive specimens were filamentous fungi positive, and 22 of 998 (2.20%) specimens were yeast positive. Among the 998 fungal positive specimens analyzed in this study, twenty-seven (2.71%) were collected from the vitreous, twelve (1.20%) were collected from aqueous humors, thirteen (1.30%) were collected from conjunctiva, seven (0.70%) were collected from eyelid margin, three (0.30%) were collected from lachrymal, and 8 were collected from other parts. The fungal pathogens should be differentiated from the deformed corneal epithelial cells, vacuoles, amebic cyst and other tissue cells during scraping. CONCLUSIONS: The smear cytology test for the diagnosis of ocular fungal infections has advantages of higher detection rate, less time-consuming and easier operation. The identification of fungal like ingredients is very important to improve the accuracy of diagnosis of ocular fungal infections.


Asunto(s)
Infecciones Fúngicas del Ojo/diagnóstico , Adolescente , Adulto , Anciano , Niño , Preescolar , Citodiagnóstico , Infecciones Fúngicas del Ojo/microbiología , Femenino , Hongos/aislamiento & purificación , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven
8.
BMC Infect Dis ; 13: 109, 2013 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-23446269

RESUMEN

BACKGROUND: The prevalence, genotypes, and vertical transmission characteristics of human papillomavirus (HPV) among pregnant women from Nanjing, China was investigated. METHODS: Cervical cells were collected from healthy pregnant women (n = 3139; stage of gestation, 24.6 ± 2.1 weeks) for cytological evaluation and determination of HPV infection status. Exfoliated oral and genital cells were collected from neonates (<1-day-old, n = 233) whose mothers were positive for HPV DNA. We used HPV Gene Chip technology with 23 HPV genotype probes to conduct our analysis. RESULTS: Overall prevalence of HPV DNA among pregnant women was 13.4% (422/3139). The most frequently detected HPV genotypes were HPV-16 (29.6%, 125/422), -18 (14.7%, 62/422), and -58 (14.2%, 60/422). The rate of concordance for HPV DNA in maternal-neonatal pairs was 23.6% (55/233), with HPV type-specific concordance occurring in 26 cases. A higher prevalence of HPV DNA was apparent in female neonates compared with males (17.7 vs. 11.6%). CONCLUSIONS: The prevalence of cervical HPV DNA in pregnant women from Nanjing was low, with vertical transmission rates slightly higher. From our findings, we concluded that there was efficient vertical transmission of three HPV genotypes, with HPV-16 the most prevalent type in pregnant women and newborn babies.


Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Transmisión Vertical de Enfermedad Infecciosa , Infecciones por Papillomavirus/transmisión , Infecciones por Papillomavirus/virología , Complicaciones Infecciosas del Embarazo/virología , Adulto , Alphapapillomavirus/clasificación , China/epidemiología , Estudios Transversales , Femenino , Humanos , Recién Nacido , Masculino , Oportunidad Relativa , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/patología , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/patología , Prevalencia , Factores de Riesgo , Adulto Joven
9.
Zhonghua Yan Ke Za Zhi ; 49(10): 878-83, 2013 Oct.
Artículo en Chino | MEDLINE | ID: mdl-24433688

RESUMEN

OBJECTIVE: To summarize the clinical characteristics and the therapy effect of blepharitis patients in clinic. METHODS: Retrospective case series study.Four hundred and thirty-eight patients were diagnosed clinically as blepharitis in Beijing Tongren Hospital from Jan 2009 to July 2012. Analyzed the general states of health, case history, and the clinical manifestation, to summarize the clinical characteristics of blepharitis. The patients were clinically degree indexing and treated appropriately. After 1-2 courses of the treatment, the effect was analyzed.main outcome measures:manifestation of lid margin, corneal, conjunctiva, and the results of tear tests. RESULT: Four hundred and thirty-eight patients were recorded, from 3 to 84 years old, and the average was 40 ± 18 years old.435 (99.3%) cases were suffered with double eyes.159(26.3%) cases were males, and 279 (63.7%) cases were females. Children group had 41 cases (9.4%), which from 0 to 16 years old. Adult group (17-59 years) included 331 cases, which were 75.6% in the study. 66 cases were in aged group ( ≥ 60 years), being 15.0% in all cases.176 cases (40.2%) were on mild stage, 174 cases (39.7%) on middle stage, and 88 cases (20.1%) were on serious stage. Aged group were significantly more than children group (χ(2) = 34.575, P < 0.05).No significant difference between male and female (χ(2) = 32.877, P = 0.192). In 222 cases (50.7%) blepharitis patients complicated with correlation of keratoconjunctivitis lesions, respectively 8.5%, 75.3% and 86.4% in the mild, moderate, and severe patients. Adult group cases were significantly more than Children and aged group (χ(2) = 362.785, P < 0.05). Aged group were significantly more than Children group (χ(2) = 362.785, P < 0.05). 303 cases (69.2%)were with tear abnormal. The moderate and serious patients were more suffered with tear abnormal than mild patients (χ(2) = 64.438, P = 0.000). Patients were followed up for 1.5 to 27 months, mean 8 months. According to different extent of blepharitis, patients were given 1 courses of treatment.333 cases were clinical recovery, and the other cases were improved obviously. CONCLUSIONS: Blepharitis occurs mainly in adults.It always complicate with dry eye and keratoconjunctival lesions.It is needed pay attention to by Ophthalmologist. The diagnosis and grade is based on typical clinical symptoms. The treatment according different grades should focus on the correct handling of the palpebral margin.


Asunto(s)
Blefaritis/diagnóstico , Blefaritis/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
10.
FEBS Lett ; 585(15): 2437-44, 2011 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-21726557

RESUMEN

The molecular mechanism responsible for the regulation of GDNF in Sertoli cells remains largely unknown. In the present study, FSH induced the expression of Nur77 and GDNF in mouse testis tissue and human fetal Sertoli cells. Moreover, FSH increased the number of A spermatogonia co-cultured with Sertoli cells. In the additional assays, Nur77 was observed to directly regulate GDNF transcription. Furthermore, overexpression of Nur77 and siRNA-mediated knockdown of Nur77 affected levels of GDNF mRNA and protein in primary human fetal Sertoli cells. These results indicate that FSH-induced Nur77 regulates the expression of GDNF in Sertoli cells to stimulate the proliferation of A spermatogonia in vitro.


Asunto(s)
Proliferación Celular , Hormona Folículo Estimulante/fisiología , Factor Neurotrófico Derivado de la Línea Celular Glial/biosíntesis , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/biosíntesis , Células de Sertoli/metabolismo , Espermatogonias/citología , Animales , Células Cultivadas , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Humanos , Masculino , Ratones , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Espermatogonias/metabolismo , Transcripción Genética , Activación Transcripcional
11.
Curr Microbiol ; 62(3): 1056-61, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21120656

RESUMEN

The effect of H(2)O(2) supplement on cell growth and ß-carotene productions in recombinant Saccharomyces cerevisiae CFW-01 and CFW-01 ctt1 deficiency in cytosolic catalase were investigated in shaking flasks. The results showed that supplement of H(2)O(2) (0.5 and 1.0 mM) can significantly stimulate the ß-carotene production. However, ß-carotene levels of CFW-01 ctt1Δ under 0.5 and 1 mM H(2)O(2) were 16.7 and 36.7% lower than those of CFW-01, respectively. Although lacking cytosolic catalase, no significant differences in cell growth were observed between CFW-01 ctt1Δ and CFW-01 under the same level of H(2)O(2) stress. These results suggest that ß-carotene can act as an antioxidant to protect the recombinant yeast from H(2)O(2) oxidative damage in the absence of cytosolic catalase. However, catalase still plays an important role in the production of ß-carotene under H(2)O(2) stress. If catalase can not timely decompose H(2)O(2), the free radicals such as OH· derived from H(2)O(2) can result in decrease of ß-carotene concentration. Therefore, in the production of ß-carotene by H(2)O(2) stress, not only the level of oxidative stress, but also the activities of catalase in cells should be considered.


Asunto(s)
Catalasa/metabolismo , Peróxido de Hidrógeno/toxicidad , Estrés Oxidativo , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/metabolismo , Estrés Fisiológico , beta Caroteno/metabolismo , Antioxidantes/metabolismo , Organismos Modificados Genéticamente , Recombinación Genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo
12.
Zhonghua Yan Ke Za Zhi ; 46(5): 432-6, 2010 May.
Artículo en Chino | MEDLINE | ID: mdl-20654218

RESUMEN

OBJECTIVE: To study the morphological characteristics in corneal smear of acanthamoeba keratitis. METHODS: Experimental study. From May 1991 to December 2007, in Department of Microbiology, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, 159 cases with acanthamoeba keratitis were analyzed for the laboratory results and clinical data. Giemsa's stained smear and wet-mount preparation of 159 cases were observed, all the results of cytology be photographed as the records. RESULTS: Among the 159 cases with acanthamoeba keratitis, 131 patients (82.4%) were positive on smear, and 110 cases (69.2%) were positive in culture of amoeba. The detection positive rate of smear was apparently higher than culture. Typical trophozoites, pre-encystment trophozoites, mature cysts and empty cysts could be observed by smear. So it is an important method for the clinical diagnosis. The edema and dissolved corneal epithelial cells, exudate cells, arthrospores or chlamydoconidium of mycelial fungus, vacuoles, lipid droplet and medicine crystallization should be differentiated with the pathogen. The movement of trophozoites could mainly be observed through wet-mount preparation. CONCLUSION: The detection of typical features of trophozoites, pre-encystment trophozoites, mature cysts and empty cysts by corneal smear is important for the etiological diagnosis of acanthamoeba keratitis.


Asunto(s)
Queratitis por Acanthamoeba/diagnóstico , Córnea/parasitología , Acanthamoeba , Adolescente , Adulto , Anciano , Animales , Niño , Femenino , Técnicas de Preparación Histocitológica , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
13.
Zhonghua Yan Ke Za Zhi ; 45(5): 452-5, 2009 May.
Artículo en Chino | MEDLINE | ID: mdl-19576070

RESUMEN

OBJECTIVE: To assess in vitro susceptibility of the fusidic acid, vancomycin, tobramycin and ofloxacin for 8 kinds of ocular gram-positive bacteria. METHODS: It was an experimental study. One hundred strains of ocular gram-positive bacterial isolates selected from Beijing Institute of Ophthalmology, cultivated and identified by the routine, were tested for their susceptibilities to fusidic acid, vancomycin, tobramycin and ofloxacin, with in vitro by the Kirby-Bauer disk diffusion method. Significant differences between groups were evaluated by SPSS 11.5 chi-square test of four-fold table. RESULTS: In the study, the percentage of susceptibility for in vitro gram-positive bacterial isolates to tobramycin, ofloxacin, vancomycin and fusidic acid was 55.0%, 65.0%, 98.0% and 53.0%. The susceptibility to vancomycin was significantly higher than to tobramycin, ofloxacin and fusidic acid (chi(2) = 51.425, 36.113, 54.737; P < 0.05). The susceptibility of common staphylococci to fusidic acid (85.5%) was just lower than to vancomycin (100.0%) (chi(2) = 6.605, P < 0.05), but was significantly higher than to tobramycin (58.2%) and ofloxacin (54.5%) (chi(2) = 10.106, 12.511; P < 0.05). The susceptibility of common streptococcus to fusidic acid (0.0%) was lower than to vancomycin (100.0%) and ofloxacin (85.0%) (chi(2) = 40.000, 29.565; P < 0.05), but the susceptibility to fusidic acid and tobramycin (15.0%) were equivalent (chi(2) = 1.441, P > 0.05). The gram-positive bacilli and nocardia showed significantly lower susceptibility to fusidic acid (24.0%) than that to the other three antibiotics (tobramycin 80.0%, ofloxacin 72.0%, vancomycin 92.0%) (chi(2) = 23.727, 22.430, 11.538; P < 0.05). CONCLUSION: The in vitro susceptibility of fusidic acid to staphylococci is higher, while to streptococcus and gram-positive bacilli is obviously lower than other three kinds of antibiotics.


Asunto(s)
Antibacterianos/farmacología , Ácido Fusídico/farmacología , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/clasificación , Pruebas de Sensibilidad Microbiana , Ofloxacino/farmacología , Staphylococcus/efectos de los fármacos , Tobramicina/farmacología , Vancomicina/farmacología
14.
Zhonghua Yan Ke Za Zhi ; 45(2): 141-5, 2009 Feb.
Artículo en Chino | MEDLINE | ID: mdl-19573335

RESUMEN

OBJECTIVE: To analyze the types, distribution characteristics and in vitro susceptibility of antibiotic agents of ocular non-viral microbial isolates in children. METHODS: Experimental research.785 specimens obtained from children below the age of 14 in Beijing Tongren Hospital during 1999 to 2004 were cultured and identified for bacterium, fungus and Acanthamoeba respectively at Beijing Institute of Ophthalmology. Microbial culture-positive rate, susceptibility patterns and the organisms distribution of positive cultures were retrospectively analyzed. The results were statistical analyzed by chi(2). RESULTS: Of the 785 specimens, 211 were culture positive. The percentage of positive culture was 26.88%. Of those positive cultures, 176 (83.41%) had pure bacterial infections, 32 (15.17%) had pure fungal infections, and 3 (1.42%) had pure cultures of Acanthamoeba. Of the 176 bacterial positive cultures, polymicrobial infection was present in 38 cases (33 bacterial, 5 fungal and bacterial). Of 214 bacterial isolates, the most common isolate was Neisseria gonorrhoeae (39/214, 18.22%), followed by Staphylococcus epidermidis (37/214, 17.29%), and Corynebacterium spp. (36/214, 16.82%). The most common fungal pathogen isolated was Fusarium spp. representing 25.00% (8/32) of all positive fungal cultures, followed by Aspergillus spp. (15.63%, 5/32). The sensitivity of tobramycin, norfloxacin, gentamicin, amikacin, ciprofloxacin, ofloxacin, rifampicin and levofloxacin of bacteria was 62.57%, 64.94%, 70.06%, 70.87%, 71.19%, 73.89%, 85.80% and 87.50%. Gram-positive isolates were susceptible to levofloxacin. Gram-negative isolates showed high susceptible to ciprofloxacin, ofloxacin and levofloxacin. The fungal isolates were most susceptible to natamycin, followed by terbinafine, but resistant to fluconazole. CONCLUSIONS: Bacteria are the most common pathogens in non-viral microbial eye infection in children. Neisseria gonorrhoeae, Staphylococcus epidermidis, and Corynebacterium spp. are the most common bacterial pathogens, which are highly susceptible to levofloxacin and rifampicin. Fusarium spp. and Aspergillus spp. are the most common fungal pathogens, which are highly susceptible to natamycin but resistant to fluconazole.


Asunto(s)
Bacterias/aislamiento & purificación , Farmacorresistencia Microbiana , Infecciones del Ojo/microbiología , Hongos Mitospóricos/aislamiento & purificación , Adolescente , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Niño , Preescolar , Femenino , Fluconazol/farmacología , Humanos , Lactante , Recién Nacido , Levofloxacino , Masculino , Pruebas de Sensibilidad Microbiana , Hongos Mitospóricos/efectos de los fármacos , Ofloxacino/farmacología , Estudios Retrospectivos , Rifampin/farmacología
15.
Zhonghua Yan Ke Za Zhi ; 45(1): 61-5, 2009 Jan.
Artículo en Chino | MEDLINE | ID: mdl-19484933

RESUMEN

OBJECTIVE: To establish a method to measure mutant prevention concentration (MPC) in vitro, and to measure MPC of antibacterial agents for ocular bacteria caused keratitis. METHODS: It was an experimental study. Forty strains of ocular bacteria were separated from cornea in Beijing Institute of Ophthalmology, which included 8 strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Pseudomonas aeruginosa and Klebsiella pneumoniae respectively. The minimal inhibitory concentration (MIC) of the levofloxacin (LVF), ofloxacin (OFL), ciprofloxacin (CIP), norfloxacin (NFL), tobramycin (TOB) and chloromycetin (CHL) were determined by agar dilution method from National Committee of Clinical Laboratory Standard (NCCLS). The MPC were measured by accumulate-bacterial methods with bacterial population inoculated more than 1.2 x 10(10) colony forming units per milliliter with Mueller-Hinton broth and tryptic soy agar plate. With the software of SPSS 11.0, the datum such as the range of MIC, MPC, MIC90 and MPC90 were calculated, and the selection index (MPC90/ MI90) and mutant selection window (MSW) were obtained. RESULTS: The MI90 of LVF and TOB (4 mg/L) to Staphylococcus aureus strains were the lowest. CIP showed the lowest MIC90 (0.25 mg/L) to Pseudomonas aeruginosa among six kinds of antibacterial agents. The MIC90 of LVF to Staphylococcus epidermidis (256 mg/L), Streptococcus pneumoniae (1 mg/L) and Klebsiella pneumoniae (0.25 mg/L) were lower than other antibacterial agents. The MPC90, MSW and the MPC90/MIC90 of levofloxacin showed lower values compared with other antibacterial medicines. From all the datum, the MIC90 of CHL was the highest and the activity was the weakest. Although the activity of LVF was higher to every kind of bacteria, CIP had the highest activity antibacterial to Pseudomonas aeruginosa. The capacity of CHL and TOB was weaker than Quinolones for restricting resistant mutants on ocular bacteria. LVF had the strongest capacity for restricting resistant mutants among Quinolones. CONCLUSION: LVF has better antibacterial effects and stronger capacity for restricting the selection of resistant mutants on ocular bacteria than other antibacterial agents.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Infecciones Bacterianas del Ojo/microbiología , Antibacterianos/administración & dosificación , Antibacterianos/aislamiento & purificación , Humanos , Queratitis/microbiología , Pruebas de Sensibilidad Microbiana , Mutación
16.
Zhongguo Dang Dai Er Ke Za Zhi ; 11(11): 892-6, 2009 Nov.
Artículo en Chino | MEDLINE | ID: mdl-20113655

RESUMEN

OBJECTIVE: To investigate the clinical utility of multiplex ligation-dependent probe amplification (MLPA) for detecting 22q11 deletion and duplication in congenital heart disease (CHD) cases and to study the incidence of 22q11 deletion and duplicaton in different kinds of CHD. METHODS: Forty eight probes of which 25 located in 22q11 low copy number region (LCR 22s A-H), 7 in 22q11 surrounding region (CES, 22q13) and 16 in chromosomes 4, 8, 10 and 17 were selected to detect 22q11 deletion and duplication in 181 preoperative children with CHD and 14 fetuses with serious CHD or CHD with multiple malformations. In these cases, karyotype analysis was also performed. RESULTS: MLPA demonstrated that 7 cases had 22q11 deletion [6 cases from CLTCL1 to LZTR1(LCR A-D) and 1 case from CLTCL1 to PCQAP (LCR A-C)] and that 1 case had 22q11 duplication,spanning from ZNF74 to LZTR1(LCR B-D). The phenotypes of heart defect included ventricular septal defect, atrioventricular septal defect, pulmonary stenosis and tetralogy of Fallot. Karyotype analysis showed that 1 case had 21q deletion [46, XY, 21q], 1 case had mosaic trisomy 8 [47,XY, +8/46, XY(1:2)] and 4 cases had trisomy 21. One of the 4 cases with trisomy 21 had concurrent 22q11 duplication. CONCLUSIONS: MLPA is a rapid, sensitive, site specific and relatively inexpensive method for diagnosis of 22q11 deletion and duplication in CHD. 22q11 deletion and duplication may cause various kinds of CHD, suggesting that genetic detection should be performed routinely in CHD patients.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 22 , Duplicación de Gen , Cardiopatías Congénitas/genética , Técnicas de Amplificación de Ácido Nucleico/métodos , Adolescente , Femenino , Humanos , Recién Nacido , Masculino
17.
Zhonghua Yan Ke Za Zhi ; 44(3): 233-6, 2008 Mar.
Artículo en Chino | MEDLINE | ID: mdl-18785547

RESUMEN

OBJECTIVE: To assess the in vitro susceptibilities of ocular bacterial isolates to Gatifloxacin and other fluoroquinolones which are often used in ophthalmic treatment. METHODS: Non-randomized, non-comparative, retrospective study. Ocular bacterial isolates (n = 619) from Beijing Institute of Ophthalmology were tested for their susceptibilities to gatifloxacin, ciprofloxacin, ofloxacin and levofloxacin in vitro by the Kirby-Bauer disk diffusion method. RESULTS: The total number of ocular bacterial isolates was 619 from January, 2005 to December, 2006 including gram-positive cocci 372(60.1%), gram-negative cocci 7 (1.1%), gram-positive bacilli 60 (9.7%), gram-negative bacilli 177 (28.6%), other 3 (0.5%). The percentage of susceptibility in total ocular bacterial isolates to gatifloxacin, ciprofloxacin, ofloxacin and levofloxacin was 88.4%, 72.1%, 64.8% and 54.4%. The susceptibility of Staphylococcus species to gatifloxacin (89.9%) was significantly higher than ciprofloxacin (38.8%), ofloxacin (48.2%) and levofloxacin (61.6%). Streptococcus species showed significantly higher susceptibility to gatifloxacin (93.2%), levofloxacin (89.2%) and ofloxacin (87.8%) than ciprofloxacin (62.2%). The susceptibility of gram-positive bacilli to gatifloxacin (86.7%) was significantly higher than ciprofloxacin (58.3%); All above differences are significant (P < 0.0083). Gram-negative cocci, enteric bacilli family and Pseudomonas species have the equivalent susceptibility to gatifloxacin, ciprofloxacin, ofloxacin and levofloxacin (P > 0.05). CONCLUSIONS: Most of ocular bacterial are susceptible to gatifloxacin in vitro, especially gram-positive bacteria including Staphylococcus species, Streptococcus species and gram-positive bacilli.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Ojo/microbiología , Fluoroquinolonas/farmacología , Ciprofloxacina/farmacología , Gatifloxacina , Humanos , Levofloxacino , Pruebas de Sensibilidad Microbiana , Ofloxacino/farmacología
18.
Biotechnol Appl Biochem ; 51(Pt 2): 73-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18208374

RESUMEN

Polyphenols, including flavonoids, are the major components of the extracts from aceraceous plants. They possess remarkable antibacterial and antitumour activity. Our study focused on whether the inhibition of the bacterial type II fatty acid synthesis system is the mechanism for the antibacterial effect of the related plant polyphenols. Extracts obtained from the fallen leaves of the Shantung maple (Acer truncatum Bunge) using different solvents, and the related pure compound PGG (1,2,3,4,6-penta-O-galloyl-beta-D-glucose), potently inhibited the FabG (beta-oxoacyl-ACP reductase) steps in the fatty-acid-elongation cycle with the IC(50) values between 0.9 and 7.2 microg/ml. An ethyl acetate extract appeared to inhibit FabG reductase in a mixed manner with NADPH, as did PGG with NADPH, demonstrating that they interfered with the binding of the cofactor to the enzyme. Gram-positive and Gram-negative bacteria and some fungi were used to evaluate the antibacterial abilities of different extract samples. The experiments showed that a higher polyphenol content of the extracts led to a more potent inhibitory capacity against FabG, thus enhancing the antibacterial efficacy.


Asunto(s)
Acer/química , Oxidorreductasas de Alcohol/antagonistas & inhibidores , Antibacterianos/farmacología , Medicamentos Herbarios Chinos/farmacología , Inhibidores Enzimáticos/farmacología , Escherichia coli/enzimología , Oxidorreductasas de Alcohol/química , Oxidorreductasas de Alcohol/aislamiento & purificación , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Sitios de Unión , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Escherichia coli/efectos de los fármacos , Hongos/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Concentración 50 Inhibidora , Cinética , Pruebas de Sensibilidad Microbiana , Hojas de la Planta/química , Especificidad de la Especie , Relación Estructura-Actividad , Factores de Tiempo
20.
Zhonghua Yan Ke Za Zhi ; 43(7): 613-7, 2007 Jul.
Artículo en Chino | MEDLINE | ID: mdl-17897550

RESUMEN

OBJECTIVE: To study clinical manifestation and pathology change of different time points of rabbit keratitis caused by non-tuberculous mycobacteria (NTM). METHODS: Forty-eight eyes from 48 rabbits were randomly divided into three groups:under-flap infection group (UFI group), under-flap infection group with corticosteroid (UFIC group) and surface infection group (SI group). The cornea infiltration area of all rabbits was observed. Bacterial quantitative culture and histopathological examination were performed. RESULTS: In the earliest stage (5 days), the cornea was cloudy and edematous. In the middle stage (7 - 14 days), cornea stromal infiltration became its major clinical sign. In the last stage (21 days), corneal neovascularization and fibrosis were developed. The mean stromal infiltration area in UFIC group was greater than those of UFI group and SI group (F = 9.362, 8.341, P < 0.05). The number of NTM in UFIC group was higher than those of UFI group and SI group (F = 411.272, P < 0.05). In histopathological examination, there were infiltrates with polymorphonuclear leukocytes (PMN) in the corneal stroma in the early stage and acid-fast bacilli was found. A plenty of lymphocytes in the cornea was found in the middle stage of NTM keratitis. In the latter stage, the fibroblast cells proliferation and corneal ulcer were cured. During the course of this infection, the number of CD4+, CD8+ T lymphocyte increased significantly, and then decreased gradually following the regress of the infection. In the stage (5 - 21 days), CD4+ T lymphocyte decreased significantly in UFIC group compared with other two groups (F = 21.907, 196.521, 12.552, 11.100, P < 0.01). CONCLUSIONS: The clinical characteristic of rabbit keratitis is the multifocal dense superficial stromal infiltrates. CD4+ T lymphocyte may play an important role in NTM keratitis.


Asunto(s)
Queratitis/microbiología , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium chelonae , Animales , Linfocitos T CD4-Positivos/inmunología , Córnea/patología , Queratitis/inmunología , Queratitis/patología , Conejos
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