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981.
We report one case with chronic postoperative endophthalmitis caused by Roseomonas species. Roseomonas spp. induced chronic endophthalmitis, which might result in misdiagnosis and delayed treatment and causes ocular damage and severe visual loss. This report is the first one related to a case with postoperative endophthalmitis secondary to Roseomonas infection. 相似文献
982.
983.
Applications of composite scaffolds comprising polyethylene oxide (PEO) and chitosan to the culture of bovine knee chondrocytes (BKC) were investigated. Here, PEO and chitosan with various weight ratios were crosslinked, refrigerated at -80 degrees C, and lyophilized. Pore surfaces of the PEO/chitosan scaffolds were chemically modified by human fibronectin for accelerating BKC adhesion and growth. The results revealed that the range of pore diameters was between 200 and 400 mum. A high content of PEO in scaffolds generated high porosity, moisture content, physical ductility, biodegradation rate, and BKC viability, as well as low Young's and compression moduli. High levels of PEO, human fibronectin, and extracellular calcium were favorable to the BKC culture, as indicated by the enhanced amounts of BKC, glycosaminoglycans, and collagen. However, a high concentration of medium potassium caused detrimental influences on the proliferation of BKC and the secretion of extracellular matrices. The present PEO/chitosan scaffolds showed enhancements in biomedical characteristics for the formation of tissue-engineered cartilage toward clinical prosthesis. 相似文献
984.
A systems analysis of the chemosensitivity of breast cancer cells to the polyamine analogue PG-11047
Wen-Lin Kuo Debopriya Das Safiyyah Ziyad Sanchita Bhattacharya William J Gibb Laura M Heiser Anguraj Sadanandam Gerald V Fontenay Zhi Hu Nicholas J Wang Nora Bayani Heidi S Feiler Richard M Neve Andrew J Wyrobek Paul T Spellman Laurence J Marton Joe W Gray 《BMC medicine》2009,7(1):1-11
Background
When this trial was initiated, the combined measles, mumps and rubella (MMR) vaccine was licensed for subcutaneous administration in all European countries and for intramuscular administration in some countries, whereas varicella vaccine was licensed only for subcutaneous administration. This study evaluated the intramuscular administration of an MMR vaccine (M-M-RvaxPro®) and a varicella vaccine (VARIVAX®) compared with the subcutaneous route.Methods
An open-label randomised trial was performed in France and Germany. Healthy children, aged 12 to18 months, received single injections of M-M-RvaxPro and VARIVAX concomitantly at separate injection sites. Both vaccines were administered either intramuscularly (IM group, n = 374) or subcutaneously (SC group, n = 378). Immunogenicity was assessed before vaccination and 42 days after vaccination. Injection-site erythema, swelling and pain were recorded from days 0 to 4 after vaccination. Body temperature was monitored daily between 0 and 42 days after vaccination. Other adverse events were recorded up to 42 days after vaccination and serious adverse events until the second study visit.Results
Antibody response rates at day 42 in the per-protocol set of children initially seronegative to measles, mumps, rubella or varicella were similar between the IM and SC groups for all four antigens. Response rates were 94 to 96% for measles, 98% for both mumps and rubella and 86 to 88% for varicella. For children initially seronegative to varicella, 99% achieved the seroconversion threshold (antibody concentrations of ≥ 1.25 gpELISA units/ml). Erythema and swelling were the most frequently reported injection-site reactions for both vaccines. Most injection-site reactions were of mild intensity or small size (≤ 2.5 cm). There was a trend for lower rates of injection-site erythema and swelling in the IM group. The incidence and nature of systemic adverse events were comparable for the two routes of administration, except varicella-like rashes, which were less frequent in the IM group.Conclusion
The immunogenicities of M-M-RvaxPro and VARIVAX administered by the intramuscular route were comparable with those following subcutaneous administration, and the tolerability of the two vaccines was comparable regardless of administration route. Integration of both administration routes in the current European indications for the two vaccines will now allow physicians in Europe to choose their preferred administration route in routine clinical practice.Trial registration
ClinicalTrials.gov NCT00432523 相似文献985.
Kristi Baker Shuo-Wang Qiao Timothy Kuo Kanna Kobayashi Masaru Yoshida Wayne I. Lencer Richard S. Blumberg 《Seminars in immunopathology》2009,31(2):223-236
Careful regulation of the body’s immunoglobulin-G (IgG) and albumin concentrations is necessitated by the importance of their
respective functions. As such, the neonatal Fc receptor (FcRn) which, as a single receptor, is capable of regulating both
of these molecules, has become an important focus of investigation. In addition to these essential protection functions, FcRn
possesses a host of other functions that are equally as critical. During the very first stages of life, FcRn mediates the
passive transfer of IgG from mother to offspring both before and after birth. In the adult, FcRn regulates the persistence
of both IgG and albumin in the serum as well as the movement of IgG, and any bound cargo, between different compartments of
the body. This shuttling allows for the movement not only of monomeric ligand but also of antigen/antibody complexes from
one cell type to another in such a way as to facilitate the efficient initiation of immune responses towards opsonized pathogens.
As such, FcRn continues to play the role of an immunological sensor throughout adult life, particularly in regions such as
the gut which are exposed to a large number of infectious antigens. Increasing appreciation for the contributions of FcRn
to both homeostatic and pathological states is generating an intense interest in the potential for therapeutic modulation
of FcRn binding. A greater understanding of FcRn’s pleiotropic roles is thus imperative for a variety of therapeutic purposes. 相似文献
986.
Linkage analysis in multivariate or longitudinal context presents both statistical and computational challenges. The permutation
test can be used to avoid some of the statistical challenges, but it substantially adds to the computational burden. Utilizing
the distributional dependencies between (defined as the proportion of alleles at a locus that are identical by descent (IBD) for a pairs of relatives, at a given
locus) and the permutation test we report a new method of efficient permutation. In summary, the distribution of for a sample of relatives at locus x is estimated as a weighted mixture of drawn from a pool of ‘representative’ distributions observed at other loci. This weighting scheme is then used to sample from the distribution of the permutation
tests at the representative loci to obtain an empirical P-value at locus x (which is asymptotically distributed as the permutation test at loci x). This weighted mixture approach greatly reduces the number of permutation tests required for genome-wide scanning, making
it suitable for use in multivariate and other computationally intensive linkage analyses. In addition, because the distribution
of is a property of the genotypic data for a given sample and is independent of the phenotypic data, the weighting scheme can
be applied to any phenotype (or combination of phenotypes) collected from that sample. We demonstrate the validity of this
approach through simulation.
Edited by David Allison. 相似文献
987.
988.
Hypothalamic astrocytes play a critical role in the regulation and support of many different neuroendocrine events, and are affected by oestradiol. Both nuclear and membrane oestrogen receptors (ERs) are expressed in astrocytes. Upon oestradiol activation, membrane‐associated ER signals through the type 1a metabotropic glutamate receptor (mGluR1a) to induce an increase of free cytoplasmic calcium concentration ([Ca2+]i). Because the expression of oxytocin receptors (OTRs) is modulated by oestradiol, we tested whether oestradiol also influences oxytocin signalling. Oxytocin at 1, 10, and 100 nm induced a [Ca2+]i flux measured as a change in relative fluorescence [ΔF Ca2+ = 330 ± 17 relative fluorescent units (RFU), ΔF Ca2+ = 331 ± 22 RFU, and ΔF Ca2+ = 347 ± 13 RFU, respectively] in primary cultures of female post‐pubertal hypothalamic astrocytes. Interestingly, OTRs interacted with mGluRs. The mGluR1a antagonist, LY 367385 (20 nm ), blocked the oxytocin (1 nm )‐induced [Ca2+]i flux (ΔF Ca2+ = 344 ± 19 versus 127 ± 11 RFU, P < 0.001). Conversely, the mGluR1a receptor agonist, (RS)‐3,5‐dihydroxyphenyl‐glycine (100 nm ), increased the oxytocin (1 nm )‐induced [Ca2+]i response (ΔF Ca2+ = 670 ± 31 RFU) compared to either compound alone (P < 0.001). Because both oxytocin and oestradiol rapidly signal through the mGluR1a, we treated hypothalamic astrocytes sequentially with oxytocin and oestradiol to determine whether stimulation with one hormone affected the subsequent [Ca2+]i response to the second hormone. Oestradiol treatment did not change the subsequent [Ca2+]i flux to oxytocin (P > 0.05) and previous oxytocin exposure did not affect the [Ca2+]i response to oestradiol (P > 0.05). Furthermore, simultaneous oestradiol and oxytocin stimulation failed to yield a synergistic [Ca2+]i response. These results suggest that the OTR signals through the mGluR1a to release Ca2+ from intracellular stores and rapid, nongenomic oestradiol stimulation does not influence OTR signalling in astrocytes. 相似文献
989.
Lynn Y. L. Shih Li-Fen Chen Wen-Jui Kuo Tzu-Chen Yeh Yu-Te Wu Ovid J. L. Tzeng Jen-Chuen Hsieh 《Cerebellum (London, England)》2009,8(2):116-126
It has been suggested that the cerebellum participates in diverse neuropsychological functions by adjusting the sensory information
acquired for the connected brain regions to support its processing capabilities. Nevertheless, the knowledge of how the cerebellum
is modulated by the sensory information is far from clear. Function magnetic resonance imaging was exploited to investigate
how the cerebellum activity and cerebrocerebellum interaction can be affected by the interaction between visual size and duration
information during visual duration discrimination. The present findings support the sensory acquisition hypothesis that the
cerebellum, together with extensive cortical networks, yields higher activation with incongruent sensory information to cope
with increasing cortical computational demand. Furthermore, comprehensive intracerebellum connections are engaged in tasks
with congruent sensory information for saving cortical computation with integrated sensory information. 相似文献
990.
Introduction Myasthenic crisis is a great threat to patients with myasthenia gravis. Usage of non-invasive ventilation (NIV) to prevent
intubation and timing of extubating of patients in myasthenic crisis are important issues though not well documented.
Methods To explore the factors predicting NIV success and extubation outcome in myasthenic crisis, we reviewed the records of 41 episodes
of myasthenia crisis.
Results NIV was applied to 14 episodes of myasthenic crisis and eight (57.1%) of them were successfully prevented from intubation.
An Acute Physiology and Chronic Health Evaluation (APACHE) II score of <6 and a serum bicarbonate level of <30 mmol/l were
independent predictors of NIV success. For patients undergoing invasive mechanical ventilation, extubation failure was observed
in 13 (39.4%) of 33 episodes, and the most common cause was sputum impaction due to a poor cough strength (61.5%). A maximal
expiratory pressure (Pemax) of ≥40 cmH2O was a good predictor of extubation success. Extubation failure led to poorer outcomes.
Conclusions NIV may be applied to those patients with a low APACHE II score and a lesser degree of metabolic compensation for respiratory
acidosis. For patients undergoing invasive mechanical ventilation, extubation failure is associated with significant in-hospital
morbidity in myasthenic crisis. Adequate levels of Pemax and cough strength correlate significantly with extubation success. 相似文献