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181.
Induction of severe inflammatory arthritis in the collagen antibody-induced arthritis (CAIA) murine model causes extensive joint damage and pain-like behavior compromising analysis. While mild models are less severe, their reduced, variable penetrance makes assessment of treatment efficacy difficult. This study aimed to compare macroscopic and microscopic changes in the paws, along with central nervous system activation between a mild and moderate CAIA model. Balb/c mice (n=18) were allocated to control, mild, and moderate CAIA groups. Paw inflammation, bone volume (BV), and paw volume (PV) were assessed. Histologically, the front paws were assessed for joint inflammation, cartilage damage, and pre/osteoclast-like cells and the lumbar spinal cord and the periaqueductal gray (PAG) region of the brain for glial reactivity. A moderate CAIA dose induced (1) significantly greater local paw inflammation, inflammatory cell infiltration, and PV; (2) significantly more osteoclast-like cells on the bone surface and within the surrounding soft tissue; and (3) significantly greater glial reactivity within the PAG compared with the mild CAIA model. These findings support the use of a moderate CAIA model (higher dose of monoclonal antibodies with low-dose lipopolysaccharide) to induce more consistent histopathological features, without excessive joint destruction.  相似文献   
182.
1. The synthesis of calcium-binding protein, a protein produced in the small intestine in response to vitamin D, was investigated with a view to determining whether calcium-binding-protein production could be correlated with the stimulation of calcium absorption by vitamin D. 2. A radioimmunological assay, which can quantitatively estimate calcium-binding-protein concentrations as low as 1μg/g wet wt., was used to detect the synthesis of soluble calcium-binding protein. 3. When used on intestinal supernatants from chicks dosed with vitamin D, calcium-binding protein was not detectable at 8h but was present after 12h at a concentration of 8.6μg/g wet wt.; in agreement with this an increase in calcium absorption due to vitamin D was detected at 12h but not at 8h. 4. The synthesis of calcium-binding protein was also monitored directly by making use of the ability of the iodinated antiserum to bind specifically to nascent calcium-binding protein chains on intestinal polyribosomes; in this way calcium-binding-protein synthesis could be detected 8h after dosage with vitamin D. Further, the binding reaction indicated a near linear increase in the calcium-binding-protein-synthesizing capacity over a 16h period. 5. From the amount of calcium-binding protein present 12 and 24h after vitamin D administration it is calculated that calcium-binding-protein mRNA is produced at approx. 1mol/min per intestinal cell. 6. It is concluded that the high correlation between the initiation of calcium-binding-protein synthesis and the stimulation of calcium absorption by vitamin D strengthens the proposal that calcium-binding protein plays an important role in calcium transport.  相似文献   
183.
The roots of Pimpinella major Huds., P. saxifraga L. and P. peregrina L. do not contain any of the furocoumarins, indicated in previous literature. The main components of roots and fruits of P. major and P. saxifraga are isoeugenol epoxy tiglic ester, isoeugenol epoxy-2-methyl butanoic ester and 4-(1′,2′-epoxypropyl)-phenyl tiglic ester. The fruit and roots of P. peregrina do not contain these components. Only the fruit of P. major contains β-bisabolene and larger amounts of bisabolangelone.  相似文献   
184.
Summary Human malignant melanoma cell lines were assayed for secretion of plasminogen activator (PA) and for growth in the nude mouse. It was observed that cell lines that were high producers of PA also grew in the nude mouse. In order to detect differences in membrane constituents of cells related to these parameters of malignancy, antisera were raised in non-human primates against the high producer (Mel A-375) and the non-producer cell of PA (SK-Mel 25). After extensive absorption the two antisera showed little or no cross-reactivity with the other cell line. Several subclones were isolated from SK-Mel 25 and assayed for PA production and growth in the nude mouse. Two sublines (S 5 and S 13) were found that produced moderate amounts of PA and grew in the nude mouse, whereas five other sublines were negative in both respects. By means of antisera against sublines it could be shown that patterns of surface antigens were distinct from that of the parental line.  相似文献   
185.
The number of airborne microorganisms in the area of large-scale composting facilities with different composting techniques (A: open facility using the intensive decomposition process [4000 t/year]. B: closed facility with compost containers [7000 t/year], C: closed facility with table-pile compositing and automatic turning equipment [22 000 t/year]) was investigated using impactor sampling systems (Andersen samplers). All counts carried out inside the closed facilities, especially during the turning process, showed values of >5.0 × 105 CFU/m3 for viable bacteria and moulds with a proportion ofAspergillus fumigatus of up to 64%. Depending on the type of facility, different median values were determined inside the plant area. Counts were highest in the immediate area around the biofilter outside of Facility C (1.7 × 104 CFU/m3 for bacteria and 9.5 × 103 CFU/m3 for moulds). In view of the high load of ambient airborne microorganisms inside the composting facilities, adequate occupational health measures are urgently required. Counts determining the hazard to neighbourhood residents at distances of between 150 and 2000 m showed, depending on the facility, annual median values of 170–330 CFU/m3 for bacteria, 75–340 CFU/m3 for moulds, and 15–52 CFU/m3 forA. fumigatus. Higher individual counts — up to 3 × 103 CFU/m3 for moulds and up to 350 CFU/m3 forA. fumigatus — were found as a result of specific climatic influences, (e.g. winds) and activities as well poor operation. Given the high proportion ofA. fumigatus in the exhaust air, this mould can serve as an indicator for the evaluation of the health risk. However, the maximum values found in the present study, may also be caused by other events in rural areas, (e.g. agricultural activities). With regard to neighbourhood residents, odour complaints are more important than pollution by microorganisms.  相似文献   
186.
In this paper we report some structural features of human seminal transferrin (HSmT) in comparison with the homologous protein purified from human serum (HSrT). In particular, the sequence of the first 13 N-terminal amino acids of HSmT shows 12/13 of identity with the first 13 N-terminal amino acids of HSrT, the ninth residue of the former protein being not definitely determined. Moreover, HSrT and HSmT analysed under the same conditions, by means of reversed phase HPLC, thiol groups determination and second derivative spectroscopy, show a different content of amino acids. In particular, HSmT exhibits mainly: i) a lower Asx/Glx ratio; ii) a reduction of about 50% in Cys residues; iii) a decrease of Tyr and Trp residues. Eventually oligosaccharide parallel analyses of HSmT and HSrT show the same glycosidic bond and almost the same sugar content (around 5.5% w/w); conversely, HSmT lacks of sialic acid residues and probably it contains fucose. These results, taken all together, could be sound of interest to a better understanding of the possible physiological roles of HSmT.  相似文献   
187.
The most active factor VIIa (FVIIa) variants identified to date carry concurrent substitutions at positions 158, 296 and 298 with the intention of generating a thrombin-mimicking motif, optionally combined with additional replacements within the protease domain [Persson, E., Kjalke, M. & Olsen, O. H. (2001) Proc. Natl Acad. Sci. USA98, 13583-13588]. Here we have characterized variants of FVIIa mutated at one or two of these positions to assess the relative importance of the individual replacements. The E296V and M298Q mutations gave an increased intrinsic amidolytic activity (about two- and 3.5-fold, respectively) compared with wild-type FVIIa. An additive effect was observed upon their combination, resulting in the amidolytic activity of E296V/M298Q-FVIIa being close to that of the triple mutant. The level of amidolytic activity of a variant was correlated with the rate of inhibition by antithrombin (AT). Compared with wild-type FVIIa, the Ca2+ dependence of the intrinsic amidolytic activity was significantly attenuated upon introduction of the E296V mutation, but the effect was most pronounced in the triple mutant. Enhancement of the proteolytic activity requires substitution of Gln for Met298. The simultaneous presence of the V158D, E296V and M298Q mutations gives the highest intrinsic activity and is essential to achieve a dramatically higher relative increase in the proteolytic activity than that in the amidolytic activity. The N-terminal Ile153 is most efficiently buried in V158D/E296V/M298Q-FVIIa, but is less available for chemical modification also in the presence of the E296V or M298Q mutation alone. In summary, E296V and M298Q enhance the amidolytic activity and facilitate salt bridge formation between the N-terminus and Asp343, E296V reduces the Ca2+ dependence, M298Q is required for increased factor X (FX) activation, and the simultaneous presence of the V158D, E296V and M298Q mutations gives the most profound effect on all these parameters.  相似文献   
188.
90% of spinal cord injury patients cannot have an ejaculation during either sexual intercourse or masturbation From 1987 to 1993: 52 patients were treated by vibratory stimulation, 21 by electrostimulation, 4 by Physostigmine. Overall success rate during vibratory stimulation is of 65% and 83% if one considers only patients with a sublesional syndrome below T10. We obtained 15 successes among 21 tetraplegic patients and 19 successes among 20 paraplegic patients. Ejaculation was always obtained within three minutes. We did not obtain any success in paraplegic patients group whose lesional level was T12, L1, L2. After having trained the couple for the technique, we realised on two occasions, during ovulation (twelfth to sixteenth day before next menstruation date), intravaginal autoinseminations with a syringe for a minimal duration of one year, necessary time to improve semen quality before treating procreation as a medical issue. Among these 52 patients treated by vibratory stimulation, only 12 couples came to take our advice in order to procreate. Out of the 12 followed up couples, we obtained 3 births and 1 current pregnancy. 16 patients out of the 21 treated by electrostimulation have an ejaculation. Out of the 30 realised ejaculations, 11 were retrograde. Semen volume and quality are much lower to what we obtained by vibratory stimulation. Actually, this technique has not allowed a pregnancy. 2 out of the 4 patients having had a treatment by Physostigmine had an ejaculation. Ejaculation by vibratory stimulation is the easiest technique and it must be proposed as a first purpose. In a second time, proposed intrarectal electrostimulation allows nearly always to get semen if a sufficient number of sympathetic thoracolumbar fibres are preserved.  相似文献   
189.
Nonsense suppressor strains of Lactococcus lactis were isolated using plasmids containing nonsense mutations or as revertants of a nonsense auxotrophic mutant. The nonsense suppressor gene was cloned from two suppressor strains and the DNA sequence determined. One suppressor is an ochre suppressor with an altered tRNAgin and the other an amber suppressor with an altered tRNAser. The nonsense suppressors allowed isolation of nonsense mutants of a lytic bacteriophage and suppressible auxotrophic mutants of L. lactis MG1363. A food-grade cloning vector based totally on DNA from Lactococcus and a synthetic polylinker with 11 unique restriction sites was constructed using the ochre suppressor as a selectable marker. Selection, following etectroporation of a suppressible purine auxotroph, can be done on purine-free medium. The pepN gene from L. lactis Wg2 was subcloned resulting in a food-grade plasmid giving a four- to fivefold increase in lysine aminopeptidase activity.  相似文献   
190.
The intensity of mitogenetic radiation was estimated from data given by Gurwitsch. The sensitivity of the biological method and of the physical methods were compared. With onion-base pulp and onion roots as mitogenetic inductors, the photographic method gave no perceptible blackening for exposures up to 184 hours. A photoelectric counter tube was described with cadmium as photoelectric metal. Its sensitivity was such that a radiation intensity of 10 to 15 quanta per cm.2 per second of the Hg line 2536 A was detectable. Spurious effects produced by the counter tube were described and means for their avoidance given. A number of different biological materials, all supposed to be excellent mitogenetic radiators, were investigated by means of the counter tube. No mitogenetic radiation could be detected.  相似文献   
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