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71.
Pseudomonas aeruginosa (P. aeruginosa) is a highly pathogenic bacteria involved in numerous diseases among which, are urinary tract infections (UTIs). The pyocyanin secreted as a virulence factor by this bacterium has many beneficial applications but its high cost remains an obstacle for its widespread use. In this study, a total of fifty urine isolates were identified as P. aeruginosa. All strains produced pyocyanin pigment with a range of 1.3–31 µg/ml. The highest producer clinical strain P21 and the standard strain PA14 were used in optimization of pyocyanin production. Among tested media, king’s A fluid medium resulted in the highest yield of pyocyanin pigment followed by nutrient broth. Growth at 37 °C was superior in pyocyanin production than growth at 30 °C. Both shaking and longer incubation periods (3–4 days) improved pyocyanin production. The pyocyanin yield was indifferent upon growth of P21 at both pH 7 and pH 8. In conclusion, the optimum conditions for pyocyanin production are to use King’s A fluid medium of pH 7 and incubate the inoculated medium at 37 °C with shaking at 200 rpm for a period of three to four days. 相似文献
72.
Xiao Zhang Xixin He Qiuhe Chen Junfeng Lu Simona Rapposelli Rongbiao Pi 《Bioorganic & medicinal chemistry》2018,26(3):543-550
Alzheimer’s disease (AD), a complex chronic progressive central nervous system degenerative disease and a public health problem of the world, often characters cognitive dysfunction accompaning aggression and depression, and may lead to death. More attentions should be paid on it because there is no modified strategy against AD till now. AD is featured with the loss of cholinergic neurons, the amyloid-beta peptide (Aβ) plaques and the neurofibrillary tangles and several hypotheses were established to explain the pathogenesis of AD. Hydroxycinnamic acids, including caffeic acid (CA) and ferulic acid (FA) are widely distributed in natural plants and fruits. CA and FA exert various pharmacological activities, including anti-inflammatory, antioxidant, neuroprotection, anti-amyloid aggregation and so on. All these pharmacological activities are associated with the treatment of AD. Here we summarized the pharmacological activities of CA and FA, and their hybrids as multi-target-directed ligands (MTDLs) against AD. The future application of CA and FA was also discussed, hoping to provide beneficial information for the development of CA- and FA-based MTDLs against AD. 相似文献
73.
Résumé Les extraits antigéniques de trois champignons entomopathogènes (Beauveria bassiana, Beauveria brongniartii et Metarhizium anisopliae), soumis à l'analyse éléctrophorétique en gel d'agar révèlent au total 23 activités enzymatiques différentes (5 oxydo-réductases et 18 hydrolases), dont 18 ont été retrouvées à l'analyse immunoélectrophorétique. La carte enzymatique de ces germes complète leur analyse immunoélectrophorétique; la comparaison des isoenzymes des divers isolats permet de mettre en évidence des différences interspécifiques et intraspécifiques.Chaque souche cryptogamique se caractérise par des profils enzymatiques particuliers. Ces résultats montrent donc que l'étude des enzymogrammes est un complément utile à l'analyse immunoélectrophorétique appliquée à la caractérisation des hyphomycètes entomopathogènes. Enfin, les souches n 44 et 51 de M. anisopliae paraissent être suffisamment apparentées pour être réunies au sein d'un même biotype. 相似文献
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76.
McGillicuddy EA Chaar CI Flynn C Villalona G Longo WE 《The Yale journal of biology and medicine》2010,83(3):113-117
Although the medical management of fistulizing Crohn's disease is improving, a subset of patients does not respond to maximal medical therapy and is referred for surgical consultation. We report a case of Crohn's colitis with an ingested foreign body resulting in a cologastric fistula. The patient underwent segmental colectomy and takedown of the cologastric fistula. At the time of laparotomy, the foreign body was found in the fistulous colonic segment. The presence of an ingested foreign body likely contributed to a rare fistula that was refractory to medical management. 相似文献
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We generated and characterized novel antibody-cytokine fusion proteins (“immunocytokines”) based on murine interleukin-7 (IL7), an immunomodulatory protein which has previously shown anti-cancer activity in preclinical models and whose human counterpart is currently being investigated in clinical trials. The sequential fusion of the clinical-stage antibody fragment scFv(F8), specific to a tumor-associated splice isoform of fibronectin, yielded an immunocytokine (termed “F8-mIL7”) of insufficient pharmaceutical quality and in vivo tumor targeting performance, with a striking dose dependence on tumor targeting selectivity. By contrast, a novel immunocytokine design (termed “F8-mIL7-F8”), in which two scFv moieties were fused at the N- and C-terminus of murine IL7, yielded a protein of excellent pharmaceutical quality and with improved tumor-targeting performance [tumor: blood ratio = 16:1, 24 h after injection]. Both F8-mIL7 and F8-mIL7-F8 could induce tumor growth retardation in immunocompetent mice, but were not able to eradicate F9 tumors. The combination of F8-mIL7-F8 with paclitaxel led to improved therapeutic results, which were significantly better compared to those obtained with saline treatment. The study indicates how the engineering of novel immunocytokine formats may help generate fusion proteins of acceptable pharmaceutical quality, for those immunomodulatory proteins which do not lend themselves to a direct fusion with antibody fragments. 相似文献
79.
A prospective epidemiologic survey on the prevalence of onychomycosis and dermatophytosis in male boarding school residents 总被引:1,自引:0,他引:1
Dermatophyte infections and onychomycosis are not usually serious in term of mortality; however, they may have significant clinical consequences such as secondary bacterial infections, chronicity, therapeutic difficulties and esthetic disfigurement in addition to serving as a reservoir of infection. Our aim was to determine the prevalence of onychomycosis and dermatophytosis in a selected high risk group, consisting of male boarding school residents. A total of 410 males inhabiting two houses were evaluated by two dermatologists. In cases of clinical suspicion, appropriate samples were taken for direct microscopy and culture. The results showed that the prevalences of tinea pedis (athletes foot) and pure pedal onychomycosis were 51.5% (n:211) and 4.4% (n:18), respectively. Thirty cases of those with tinea pedis were complicated by toenail onychomycosis. Tinea cruris was present only in five cases with tinea pedis. Interestingly 71.1% of those with tinea pedis and 45.8% of those with onychomycosis, associated with or without tinea pedis were unaware of their diseases. The most common fungal isolate was Trichophyton rubrum (76.6%) followed by Epidermophyton floccosum (11.6%), T. interdigitale (10.55%). Approximately one third of the cultures from nail specimens yielded pure growths of nondermatophyte moulds or Candida albicans. In conclusion, we found unexpectedly high prevalences of occult athletes foot and toenail onychomycosis among the male residents of student houses. Our results indicate that health-care workers of such common boarding-houses should be more aware of clinical and subclinical dermatophyte infections and onychomycosis, and have more active approaches to educational measures and management strategies to prevent further infections. To our knowledge, this is the first epidemiologic study on the prevalences of dermatophytosis and onychomycosis in boarding-houses from Turkey. 相似文献
80.