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21.
The results of analysis of a bone tissue neoplasm on the mandible of an Early Mesozoic temnospondyl amphibian Benthosuchus korobkovi Ivachnenko from the Tikhvinskoe locality (upper reaches of the Volga River, Yaroslavl oblast (Region); Lower Triassic, Lower Olenekian substage) are presented. The use of multispiral computed tomography enabled a rather well justified conclusion of the neoplastic (tumor) character of this pathological formation. Non-odontogenic osteoma is the most likely diagnosis, but hemangioma and fibrotic dysplasia cannot be ruled out either.  相似文献   
22.

Background

The global burden of bacterial infections is high and has been further aggravated by increasing resistance to antibiotics. In the search for novel antibacterials, three medicinal plants: Peperomia vulcanica, Peperomia fernandopoioana (Piperaceae) and Scleria striatinux (Cyperaceae), were investigated for antibacterial activity and toxicity.

Methods

Crude extracts of these plants were tested by the disc diffusion method against six bacterial test organisms followed by bio-assay guided fractionation, isolation and testing of pure compounds. The minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations were measured by the microdilution method. The acute toxicity of the active extracts and cytotoxicity of the active compound were performed in mice and mammalian cells, respectively.

Results

The diameter of the zones of inhibition (DZI) of the extracts ranged from 7?C13?mm on Escherichia coli and Staphylococcus aureus of which the methylene chloride:methanol [1:1] extract of Scleria striatinux recorded the highest activity (DZI?=?13?mm). Twenty-nine pure compounds were screened and one, Okundoperoxide, isolated from S. striatinux, recorded a DZI ranging from 10?C19?mm on S. aureus. The MICs and MBCs indicated that the Peperomias had broad-spectrum bacteriostatic activity. Toxicity tests showed that Okundoperoxide may have a low risk of toxicity with an LC50 of 46.88???g/mL.

Conclusions

The antibacterial activity of these plants supports their use in traditional medicine. The pure compound, Okundoperoxide, may yield new antibacterial lead compounds following medicinal chemistry exploration.  相似文献   
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Study of proteomic composition of exhaled breath condensate (EBC) is a promising non-invasive method for diagnostics of respiratory system diseases in patients. In this study the EBC proteomic composition of 53 donors, including patients with different respiratory system diseases has been investigated. Cytoskeletal keratins type II (1, 2, 3, 4, 5, 6) and cytoskeletal keratins type I (9, 10, 14, 15, 16) were invariant for all samples. Analyzing the frequency of occurrence of proteins in different groups of examined patients, several categories of proteins have been recognized: proteins found in all pathologies (dermcidin, alpha-1- microglobulin, SHROOM3), proteins simultaneously found in two groups (CSTA, LCN1, JUP, PIP, TXN), and proteins specific for a particular group (PRDX1, annexin A1/A2). The EBC analysis by HPLC-MS/MS can be used for identification of potential protein markers specific for inflammatory pulmonary diseases of infective origin (pneumonia) as well as for non-infectious diseases such as chronic obstructive pulmonary disease (COPD).  相似文献   
28.

Background  

Rasbora tawarensis is an endemic freshwater fish in Lake Laut Tawar, Aceh Province, Indonesia. Unfortunately, its status is regarded as critical endangered with populations decreasing in recent years. To date no information on the spawning activities of the fish are available. Therefore, this study provides a contribution to the knowledge on reproductive biology of R. tawarensis especially on spawning seasons as well as basic information for conservation of the species.  相似文献   
29.
Transthyretin, one of the major blood proteins, displays a variety of posttranslational modifications, including those related to the development of grave diseases, such as Alzheimer’s disease, and familial amyloid polyneuropathy. A combined analytical technique based on the use of two mass spectrometric approaches (bottom-up and top-down) has been developed in the present study to determine the role of the modified forms of transthyretin in the progression of Alzheimer’s disease. The high efficiency of this technique has been demonstrated for ten serum samples obtained from patients diagnosed with Alzheimer’s disease and healthy volunteers.  相似文献   
30.
Long-term immunization of rabbits with postsynaptic densities (PSD) from bovine brain produced an antiserum specific for PSD as judged by binding to subcellular fractions and immunohistochemical location at the light and electron microscope levels. (a) The major antigens of bovine PSD preparations were three polypeptides of molecular weight 95,000 (PSD-95), 82,000 (PSD-82), and 72,000 (PSD-72), respectively. Antigen PSD-95, also present in mouse and rat PSDs was virtually absent from cytoplasm, myelin, mitochondria, and microsomes from rodent or bovine brain. Antigens PSD-82 and PSD-72 were present in all subcellular fractions from bovine brain, especially in mitochondria, but were almost absent from rodent brain. The antiserum also contained low-affinity antibodies against tubulin. (b)Immunohistochemical studies were performed in mouse and rat brain, where antigen PSD-95 accounted for 90 percent of the antiserum binding after adsorption with purified brain tubulin. At the light microscope level, antibody binding was observed only in those regions of the brain where synapses are known to be present. No reaction was observed in myelinated tracts, in the neuronal cytoplasm, or in nonneuronal cells. Strong reactivity was observed in the molecular layer of the dentate gyrus, stratum oriens and stratum radiatum of the hippocampus, and the molecular layer of the cerebellum. Experimental lesions, such as ablation of the rat entorhinal cortex or intraventricular injection of kainic acid, which led to a major loss of PSD in well- defined areas of the hippocampal formation, caused a correlative decrease in immunoreactivity in these areas. Abnormal patterns of immunohistochemical staining correlated with abnormal synaptic patterns in the cerebella of reeler and staggerer mouse mutants. (c) At the electron microscopic level, immunoreactivity was detectable only in PSD. The antibody did not bind to myelin, mitochondria or plasma membranes. (d) The results indicate that antigen PSD-95 is located predominantly or exclusively in PSD and can be used as a marker during subcellular fractionation. Other potential uses include the study of synaptogenesis, and the detection of changes in synapse number after experimental perturbations of the nervous system.  相似文献   
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