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31.
The chemical composition and the antimicrobial activity of the essential oil isolated from the needles of endemic Dalmatian black pine (Pinus nigra ssp. dalmatica) from Croatia were investigated. The chemical composition of the essential oil was determined by GC and GC/MS analyses, and the main compounds identified were α-pinene, β-pinene, germacrene D, and β-caryophyllene. Disc-diffusion and broth-microdilution assays were used for the in vitro antimicrobial screening. The Dalmatian black pine essential oil exhibited a great potential of antibacterial activity against Gram-positive bacteria (MIC=0.03-0.50% (v/v)) and a less pronounced activity against Gram-negative bacteria (MIC=0.12-3.2% (v/v)). The volatile compounds also inhibited the growth of all fungi tested, including yeast. 相似文献
32.
Knezevic P Obreht D Curcin S Petrusic M Aleksic V Kostanjsek R Petrovic O 《Journal of applied microbiology》2011,111(1):245-254
Aims: To examine effects of various environmental factors on adsorption and inactivation of Pseudomonas aeruginosa‐specific phages: δ (family Podoviridae), J‐1, σ‐1 and 001A (family Siphoviridae) and their ability to inhibit bacterial growth and biofilm formation. Methods and Results: The phages examined in the study were clonally different, as revealed by RFLP. The temperature in the range 7–44°C had no influence on the adsorption of Podoviridae, but did affect Siphoviridae adsorption, particularly 001A. All phages were significantly stable at pH 5–9, and phages δ and 001A even at pH 3. Most of the examined carbohydrates and exopolysaccharides of the original host efficiently inactivated phage δ, while phages σ‐1 and J‐1 were inactivated considerably only by the amino acid alanine. Silver nitrate efficiently inactivated all the phages, while Siphoviridae were more resistant to povidone‐iodine. Serum of nonimmunized rats had no influence on phage inactivation and adsorption. Only phage δ showed ability to effectively inhibit in vitro bacterial growth and biofilm formation. Conclusions: The examined environmental parameters can significantly influence the adsorption and viability of Ps. aeruginosa‐specific phages. The phage δ is a good candidate for biocontrol of Ps. aeruginosa. Significance and Impact of the Study: The study provides important data on Ps. aeruginosa‐specific phage adsorption, inactivation and in vitro lytic efficacy. 相似文献
33.
RNA sequencing: advances, challenges and opportunities 总被引:5,自引:0,他引:5
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Background
The existence of neural stem and progenitor cells (together termed neural precursor cells) in the adult mammalian brain has sparked great interest in utilizing these cells for regenerative medicine strategies. Endogenous neural precursors within the adult forebrain subependyma can be activated following injury, resulting in their proliferation and migration toward lesion sites where they differentiate into neural cells. The administration of growth factors and immunomodulatory agents following injury augments this activation and has been shown to result in behavioural functional recovery following stroke.Methods and Findings
With the goal of enhancing neural precursor migration to facilitate the repair process we report that externally applied direct current electric fields induce rapid and directed cathodal migration of pure populations of undifferentiated adult subependyma-derived neural precursors. Using time-lapse imaging microscopy in vitro we performed an extensive single-cell kinematic analysis demonstrating that this galvanotactic phenomenon is a feature of undifferentiated precursors, and not differentiated phenotypes. Moreover, we have shown that the migratory response of the neural precursors is a direct effect of the electric field and not due to chemotactic gradients. We also identified that epidermal growth factor receptor (EGFR) signaling plays a role in the galvanotactic response as blocking EGFR significantly attenuates the migratory behaviour.Conclusions
These findings suggest direct current electric fields may be implemented in endogenous repair paradigms to promote migration and tissue repair following neurotrauma. 相似文献36.
A dual fate of the hindlimb muscle mass: cloacal/perineal musculature develops from leg muscle cells
The cloaca serves as a common opening to the urinary and digestive systems. In most mammals, the cloaca is present only during embryogenesis, after which it undergoes a series of septation events leading to the formation of the anal canal and parts of the urogenital tract. During embryogenesis it is surrounded by skeletal muscle. The origin and the mechanisms regulating the development of these muscles have never been determined. Here, we show that the cloacal muscles of the chick originate from somites 30-34, which overlap the domain that gives rise to leg muscles (somites 26-33). Using molecular and cell labelling protocols, we have determined the aetiology of cloacal muscles. Surprisingly, we found that chick cloacal myoblasts first migrate into the developing leg bud and then extend out of the ventral muscle mass towards the cloacal tubercle. The development of homologous cloacal/perineal muscles was also examined in the mouse. Concordant with the results in birds, we found that perineal muscles in mammals also develop from the ventral muscle mass of the hindlimb. We provide genetic evidence that the perineal muscles are migratory, like limb muscles, by showing that they are absent in metd/d mutants. Using experimental embryological procedures (in chick) and genetic models (in chick and mouse), we show that the development of the cloacal musculature is dependent on proximal leg field formation. Thus, we have discovered a novel developmental mechanism in vertebrates whereby muscle cells first migrate from axially located somites to the pelvic limb, then extend towards the midline and only then differentiate into the single cloacal/perineal muscles. 相似文献
37.
Wenming Wang Milos Tanurdzic Meizhong Luo Nicholas Sisneros Hye Ran Kim Jing-Ke Weng Dave Kudrna Christopher Mueller K Arumuganathan John Carlson Clint Chapple Claude de Pamphilis Dina Mandoli Jeff Tomkins Rod A Wing Jo Ann Banks 《BMC plant biology》2005,5(1):1-8
Background
The lycophytes are an ancient lineage of vascular plants that diverged from the seed plant lineage about 400 Myr ago. Although the lycophytes occupy an important phylogenetic position for understanding the evolution of plants and their genomes, no genomic resources exist for this group of plants.Results
Here we describe the construction of a large-insert bacterial artificial chromosome (BAC) library from the lycophyte Selaginella moellendorffii. Based on cell flow cytometry, this species has the smallest genome size among the different lycophytes tested, including Huperzia lucidula, Diphaiastrum digita, Isoetes engelmanii and S. kraussiana. The arrayed BAC library consists of 9126 clones; the average insert size is estimated to be 122 kb. Inserts of chloroplast origin account for 2.3% of the clones. The BAC library contains an estimated ten genome-equivalents based on DNA hybridizations using five single-copy and two duplicated S. moellendorffii genes as probes.Conclusion
The S. moellenforffii BAC library, the first to be constructed from a lycophyte, will be useful to the scientific community as a resource for comparative plant genomics and evolution. 相似文献38.
Bonaci-Nikolic B Nikolic MM Andrejevic S Zoric S Bukilica M 《Arthritis research & therapy》2005,7(5):R1072-R1081
Clinical and serological profiles of idiopathic and drug-induced autoimmune diseases can be very similar. We compared data
from idiopathic and antithyroid drug (ATD)-induced antineutrophil cytoplasmic antibody (ANCA)-positive patients. From 1993
to 2003, 2474 patients were tested for ANCA in the Laboratory for Allergy and Clinical Immunology in Belgrade. Out of 2474
patients, 72 (2.9%) were anti-proteinase 3 (PR3)- or anti-myeloperoxidase (MPO)-positive and their clinical and serological
data were analyzed. The first group consisted of ANCA-associated idiopathic systemic vasculitis (ISV) diagnosed in 56/72 patients:
29 Wegener's granulomatosis (WG), 23 microscopic polyangiitis (MPA) and four Churg-Strauss syndrome. The second group consisted
of 16/72 patients who became ANCA-positive during ATD therapy (12 receiving propylthiouracil and four receiving methimazole).
We determined ANCA and antinuclear (ANA) antibodies by indirect immunofluorescence; PR3-ANCA, MPO-ANCA, anticardiolipin (aCL)
and antihistone antibodies (AHA) by ELISA; and cryoglobulins by precipitation. Complement components C3 and C4, alpha-1 antitrypsin
(α1 AT) and C reactive protein (CR-P) were measured by nephelometry. Renal lesions were present in 3/16 (18.8%) ATD-treated
patients and in 42/56 (75%) ISV patients (p <0.001). Skin lesions occurred in 10/16 (62.5%) ATD-treated patients and 14/56 (25%) ISV patients (p <0.01). ATD-treated patients more frequently had MPO-ANCA, ANA, AHA, aCL, cryoglobulins and low C4 (p <0.01). ISV patients more frequently had low α1 AT (p = 0.059) and high CR-P (p <0.001). Of 16 ATD-treated patients, four had drug-induced ANCA vasculitis (three MPA and one WG), while 12 had lupus-like
disease (LLD). Of 56 ISV patients, 13 died and eight developed terminal renal failure (TRF). There was no lethality in the
ATD-treated group, but 1/16 with methimazole-induced MPA developed pulmonary-renal syndrome with progression to TRF. ANCA-positive
ISV had a more severe course in comparison with ATD-induced ANCA-positive diseases. Clinically and serologically ANCA-positive
ATD-treated patients can be divided into two groups: the first consisting of patients with drug-induced WG or MPA which resemble
ISV and the second consisting of patients with LLD. Different serological profiles could help in the differential diagnosis
and adequate therapeutic approach to ANCA-positive ATD-treated patients with symptoms of systemic disease. 相似文献
39.
40.
Cholesteryl ester transfer protein variants have differential stability but uniform inhibition by torcetrapib 总被引:2,自引:0,他引:2
Lloyd DB Lira ME Wood LS Durham LK Freeman TB Preston GM Qiu X Sugarman E Bonnette P Lanzetti A Milos PM Thompson JF 《The Journal of biological chemistry》2005,280(15):14918-14922