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701.
Objectives: To evaluate the clinical efficacy of a mouthwash and oral gel containing the antimicrobial proteins lactoperoxidase, lactoferrin and lysozyme, in a sample of elderly individuals with dry mouth. Material and methods: Twenty elderly institutionalised subjects with dry mouth and with a certain degree of independence for daily life activities were included in this pilot study. A randomised, double blind and cross‐over design was used. The study variables comprised subjective dry mouth sensation, the severity of discomfort assessed by means of a visual analogical scale (VAS), the Oral Health Impact Profile (OHIP), the presence of signs and symptoms of dry mouth, sialometry and Candida albicans culture. All the variables were recorded before and after each of the two periods of the study. Results: The 20 selected subjects we made up of 16 women and four men, with a mean age of 81.3 years. Improvement was observed on analysing the data between the first and second intervention period in terms of the OHIP values, the presence of dry mouth, and the need to drink fluids to swallow. However, the improvement in certain variables before and after treatment did not take a positive course in all cases, and some subjects even improved with placebo. Conclusions: The evaluated mouthwash and oral gel improved some subjective and clinical aspects in elderly individuals with dry mouth, though a placebo effect cannot be entirely discarded.  相似文献   
702.
To dissect the phenotypic and functional features of mucosal T lymphocytes in patients with gastric adenocarcinoma, we have used the Herpesvirus saimiri transformation procedure to achieve T-cell lines from gastric origin. Once achieved, cell function was assessed by in vitro stimulation with mitogens. CD2-specific monoclonal antibodies (alpha-CD2), alone or in combination with interleukin (IL)-2, rendered fewer counts in patients (34 408+/-3965 and 52 157+/-6473 c.p.m., respectively) than in controls (67 471+/-11 755 c.p.m., P<0.01 and 77 864+/-12 545 c.p.m., P<0.05, respectively). Likewise, CD3-based responses were defective in cancer cell lines: alpha-CD3 (54 794+/-9269 vs 86 104+/-10 341 c.p.m., P<0.01), alpha-CD3+IL-2 (57 789+/-8590 vs 88855+/-8516 c.p.m., P<0.01) and alpha-CD3+alpha-CD2 (52 130+/-7559 vs 120 852+/-16 552 c.p.m., P<0.01). Finally, IL-2 failed to adequately stimulate patient cell lines (39 310+/-4023 vs 60 945+/-9463 c.p.m., P<0.05). These results suggest that mucosal T lymphocytes in cancer patients are inherently impaired in their proliferative ability. This may be crucial in the control of tumour growth.  相似文献   
703.
The halophilic bacteria Halomonas eurihalina produces an exopolysaccharide (EPS) of potential interest for biotechnological applications. To study the characteristics of this bacteria and others like it, we have developed an efficient chemical mutation technique using hydroxylamine and, in this way, have obtained non-mucoid mutants of its F2-7 strain. We have characterised the phenotypes of the mutants via nutritional, biochemical and physiological tests and by their susceptibility to antimicrobial agents and heavy metals. These mutants will be used as recipient tools in further studies to discover the genetic determinants for the synthesis of EPS.  相似文献   
704.
Species of Echium are clearly entomophilous, but they release great amounts of pollen into the atmosphere with its consequent anemophilous transport, because their high pollen production, the smallness of the grains, and the exserted position of their anthers. Using three volumetric airborne sporetraps in Extremadura (SW of Spain) between 1994 and 1998, we found that Echium pollen reached pollen concentrations similar to or greater than other anemophilous plants. The main pollination period appeared from April to June. The maximum peak daily concentration reached 35.9 grains/m3 and the annual recorded totals showed interannual variations between 64.2 and 614.4. Correlations were calculated between the daily pollen concentrations and the meteorological parameters rain, temperature, wind direction and velocity and relative humidity. Wind direction seems to be significant, warm dry air seems to facilitate the release of pollen into the atmosphere and increase its concentrations. Hourly pollen concentration reached a maximum between 11:00 and 12:00 and a minimum at 07:00, and the patterns were very similar in the three localities studied. This would indicate that the presence of Echium pollen in the atmosphere is related to the processes of anthesis of the populations near the traps, and would not correspond to a model of transport from distant zones.  相似文献   
705.
Polycomb group (PcG) proteins are epigenetic chromatin modifiers involved in heritable gene repression. Two main PcG complexes have been characterized. Polycomb repressive complex 2 (PRC2) is thought to be involved in the initiation of gene silencing, whereas Polycomb repressive complex 1 (PRC1) is implicated in the stable maintenance of gene repression. Here, we investigate the kinetic properties of the binding of one of the PRC1 core components, BMI1, with PcG bodies. PcG bodies are unique nuclear structures located on regions of pericentric heterochromatin, found to be the site of accumulation of PcG complexes in different cell lines. We report the presence of at least two kinetically different pools of BMI1, a highly dynamic and a less dynamic fraction, which may reflect BMI1 pools with different binding capacities to these stable heterochromatin domains. Interestingly, PRC2 members EED and EZH2 appear to be essential for BMI1 recruitment to the PcG bodies. Furthermore, we demonstrate that the maintenance DNA methyltransferase DNMT1 is necessary for proper PcG body assembly independent of DNMT-associated histone deacetylase activity. Together, these results provide new insights in the mechanism for regulation of chromatin silencing by PcG proteins and suggest a highly regulated recruitment of PRC1 to chromatin.  相似文献   
706.
The use of AI in pigs has dramatically expanded in the last few years. New methodological advances in AI are required to serve the requirements of new sperm technologies, such as the use of low dose AI, because the use of cervical AI has a very low efficiency leading to low fertility results. One of the strategies devised to meet these requirements is the deposition of semen near the site of fertilization in the oviduct. Using deep intrauterine insemination with a specially designed catheter, a 20-fold reduction in the number of freshly and diluted inseminated spermatozoa can be achieved without decreasing farrowing rates. Moreover, an advantage of deep intrauterine insemination is the possibility of using processed, 'weaker' spermatozoa such as those that have been frozen-thawed or sex-sorted. Although deep intrauterine insemination should be of benefit to the pig industry, more investigations are needed to understand the mechanisms related to sperm colonization of the oviducts and identify the minimal sperm numbers needed to obtain maximal fertility results for processed and unprocessed boar spermatozoa.  相似文献   
707.
Recent data from multiple laboratories indicate that upon infection, many different families of viruses hijack the dynein motor machinery and become transported in a retrograde manner towards the cell nucleus. In certain cases, one of the dynein light chains, LC8, is involved in this interaction. Using a library of overlapping dodecapeptides synthesized on a cellulose membrane (pepscan technique) we have analyzed the interaction of the dynein light chain LC8 with 17 polypeptides of viral origin. We demonstrate the strong binding of two herpesvirus polypeptides, the human adenovirus protease, vaccinia virus polymerase, human papillomavirus E4 protein, yam mosaic virus polyprotein, human respiratory syncytial virus attachment glycoprotein, human coxsackievirus capsid protein and the product of the AMV179 gene of an insect poxvirus to LC8. Our data corroborate the manipulation of the dynein macromolecular complex of the cell during viral infection and point towards the light chain LC8 as one of the most frequently used targets of virus manipulation.  相似文献   
708.
709.
OBJECTIVE: To assess the utility of fine needle aspiration cytology in the diagnosis of sialadenitis with crystalloid formation. STUDY DESIGN: In 15 cases, salivary gland masses were aspirated using a disposable, 20-mL syringe and 25-gauge needles, maintaining negative pressure. Smears routinely were air dried and stained by Diff-Quik (Dade Behring AG, Düdingen, Germany). Occasionally smears were fixed in alcohol and stained by the Papanicolaou method. RESULTS: The smears showed large numbers of non-birefringent crystalloids of varying sizes and shapes. The crystalloids stained deep blue with Diff-Quik and bright orange with Papanicolaou stain. Multinucleated histiocytes, neutrophilic leukocytes and benign salivary gland parenchyma were found, also. CONCLUSION: Fine needle aspiration cytology provides an accurate diagnosis of sialadenitis with crystalloids and is useful for avoiding unnecessary surgery.  相似文献   
710.
BACKGROUND: Heterotopic islands of salivary tissue are commonly found in the intraparotid lymph nodes and, less commonly, within extraparotid cervical nodes. Salivary gland tumors, both benign and malignant, can develop within this ectopic salivary tissue. CASES: Two patients presented with a solitary, painless mass in the cervical region. Fine needle aspiration cytology was performed, and the smears revealed a mixture of intermediate and mucus-secreting cells associated with extracellular mucin. The tumors were removed, and the diagnosis of mucoepidermoid carcinoma was confirmed by histologic study. CONCLUSION: The finding of a malignant cervical salivary gland tumor does not necessarily represent a metastasis from an occult site.  相似文献   
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