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101.

Background

Orbital marginal zone B-cell lymphoma (OAML) constitutes for the most frequent diagnosis in orbital lymphoma. Relatively little data, however, have been reported in larger cohorts of patients staged in a uniform way and no therapy standard exists to date.

Material and Methods

We have retrospectively analyzed 60 patients diagnosed and treated at our institution 1999–2012. Median age at diagnosis was 64 years (IQR 51–75) and follow-up time 43 months (IQR 16–92). All patients had undergone uniform extensive staging and histological diagnosis was made by a reference pathologist according to the WHO classification.

Results

The majority of patients presented with stage IE (n = 40/60, 67%), three had IIE/IIIE and the remaining 17 stage IVE. Seven patients with IVE had bilateral orbital disease whereas the others showed involvement of further organs. Treatment data were available in 58 patients. Local treatment with radiotherapy (14/58, 24%) or surgery (3/58, 5%) resulted in response in 82% of patients. A total of 26 patients (45%) received systemic treatment with a response rate of 85%. Nine patients received antibiotics as initial therapy; response rate was 38%. Watchful-waiting was the initial approach in 6/58 patients. In total 28/58 patients (48%) progressed and were given further therapy. Median time-to-progression in this cohort was 20 months (IQR 9–39). There was no difference in time-to-progression after first-line therapy between the different therapy arms (p = 0.14). Elevated beta-2-microglobulin, plasmacytic differentiation, autoimmune disorder and site of lymphoma were not associated with a higher risk for progress.

Conclusion

Our data underscore the excellent prognosis of OAML irrespective of initial therapy, as there was no significant difference in time-to-progression and response between local or systemic therapy. In the absence of randomized trials, the least toxic individual approach should be chosen for OAML.  相似文献   
102.
Based on pre-DNA racial/color methodology, clinical and pharmacological trials have traditionally considered the different geographical regions of Brazil as being very heterogeneous. We wished to ascertain how such diversity of regional color categories correlated with ancestry. Using a panel of 40 validated ancestry-informative insertion-deletion DNA polymorphisms we estimated individually the European, African and Amerindian ancestry components of 934 self-categorized White, Brown or Black Brazilians from the four most populous regions of the Country. We unraveled great ancestral diversity between and within the different regions. Especially, color categories in the northern part of Brazil diverged significantly in their ancestry proportions from their counterparts in the southern part of the Country, indicating that diverse regional semantics were being used in the self-classification as White, Brown or Black. To circumvent these regional subjective differences in color perception, we estimated the general ancestry proportions of each of the four regions in a form independent of color considerations. For that, we multiplied the proportions of a given ancestry in a given color category by the official census information about the proportion of that color category in the specific region, to arrive at a "total ancestry" estimate. Once such a calculation was performed, there emerged a much higher level of uniformity than previously expected. In all regions studied, the European ancestry was predominant, with proportions ranging from 60.6% in the Northeast to 77.7% in the South. We propose that the immigration of six million Europeans to Brazil in the 19th and 20th centuries--a phenomenon described and intended as the "whitening of Brazil"--is in large part responsible for dissipating previous ancestry dissimilarities that reflected region-specific population histories. These findings, of both clinical and sociological importance for Brazil, should also be relevant to other countries with ancestrally admixed populations.  相似文献   
103.
Biofilters operated for the microbial oxidation of landfill methane at two sites in Northern Germany were analysed for the composition of their methanotrophic community by means of diagnostic microarray targeting the pmoA gene of methanotrophs. The gas emitted from site Francop (FR) contained the typical principal components (CH4, CO2, N2) only, while the gas at the second site Müggenburger Strasse (MU) was additionally charged with non-methane volatile organic compounds (NMVOCs). Methane oxidation activity measured at 22 degrees C varied between 7 and 103 microg CH4 (g dw)(-1) h(-1) at site FR and between 0.9 and 21 microg CH4 (g dw)(-1) h(-1) at site MU, depending on the depth considered. The calculated size of the active methanotrophic population varied between 3 x 10(9) and 5 x 10(11) cells (g dw)(-1) for biofilter FR and 4 x 10(8) to 1 x 10(10) cells (g dw)(-1) for biofilter MU. The methanotrophic community in both biofilters as well as the methanotrophs present in the landfill gas at site FR was strongly dominated by type II organisms, presumably as a result of high methane loads, low copper concentration and low nitrogen availability. Within each biofilter, community composition differed markedly with depth, reflecting either the different conditions of diffusive oxygen supply or the properties of the two layers of materials used in the filters or both. The two biofilter communities differed significantly. Type I methanotrophs were detected in biofilter FR but not in biofilter MU. The type II community in biofilter FR was dominated by Methylocystis species, whereas the biofilter at site MU hosted a high abundance of Methylosinus species while showing less overall methanotroph diversity. It is speculated that the differing composition of the type II population at site MU is driven by the presence of NMVOCs in the landfill gas fed to the biofilter, selecting for organisms capable of co-oxidative degradation of these compounds.  相似文献   
104.
The interaction between surface components on the invading pathogen and host cells such as platelets plays a key role in the regulation of endovascular infections. However, the mechanisms mediating Staphylococcus aureus binding to platelets under shear remain largely unknown. This study was designed to investigate the kinetics and molecular requirements of platelet-S. aureus interactions in bulk suspensions subjected to a uniform shear field. Hydrodynamic shear-induced collisions augment platelet-S. aureus binding, which is further potentiated by platelet activation with stromal derived factor-1beta. Peak adhesion efficiency occurs at low shear (100 s(-1)) and decreases with increasing shear. The molecular interaction of platelet alpha(IIb)beta(3) with bacterial clumping factor A through fibrinogen bridging is necessary for stable bacterial binding to activated platelets under shear. Although this pathway is sufficient at low shear (相似文献   
105.
N 5,N 10-Methenyltetrahydromethanopterin cyclohydrolase (Mch) is an enzyme involved in methanogenesis from CO2 and H2 which represents the energy metabolism of Methanopyrus kandleri, a methanogenic Archaeon growing at a temperature optimum of 98°C. The gene mch from M. kandleri was cloned, sequenced, and expressed in Escherichia coli. The overproduced enzyme could be purified in yields above 90% in one step by chromatography on phenyl Sepharose in 80% ammonium sulfate. From 3.5 g cells (250 mg protein), approximately 18 mg cyclohydrolase was obtained. The purified enzyme showed essentially the same catalytic properties as the enzyme purified from M. kandleri cells. The primary structure and properties of the cyclohydrolase are compared with those of the enzyme from Methanococcus jannaschii (growth temperature optimum 85°C), from Methanobacterium thermoautotrophicum (65°C), and from Methanosarcina barkeri (37°C). Of the four enzymes, that from M. kandleri has the lowest isoelectric point (3.8) and the lowest hydrophobicity of amino acid composition. Besides, it has the highest relative content of glutamate, leucine, and valine and the lowest relative content of isoleucine, serine, and lysine. Some of these properties are unusual for enzymes from hyperthermophilic organisms. They may reflect the observation that the cyclohydrolase from M. kandleri is not only adapted to hyperthermophilic conditions but also to the high intracellular concentrations of lyotrophic salts prevailing in this organism. Received: July 14, 1997 / Accepted: August 28, 1997  相似文献   
106.
107.
A series of N-fluoroalkyl-8-(6-methoxy-2-methylpyridin-3-yl)-2,7-dimethyl-N-alkylpyrazolo[1,5-a][1,3,5]triazin-4-amines were prepared and evaluated as potential CRF1R PET imaging agents. Optimization of their CRF1R binding potencies and octanol-phosphate buffer phase distribution coefficients resulted in discovery of analog 7e (IC50 = 6.5 nM, log D = 3.5).  相似文献   
108.
109.

Background, aim, and scope  

We report the environmental assessment of the cultivation cycle of cauliflower (Brassica oleracea L. var. botrytis), chosen due to its high levels of natural bioactive compounds, using different fertilization practices. The functional units used during the impact assessment were linked with the quantity produced, considering different units of commercialization, or with the cauliflower quality, considering its antioxidant compounds content. Although nutrient content has been described and used as a possible functional unit, using antioxidant compounds as a functional unit has not previously been published.  相似文献   
110.
A cell has been isolated from explanted rabbit liver which contains, during all phases of its growth in culture, hundreds of lipid-rich particles with a distinct limiting membrane. The cell grows logarithmically with a generation time of 19 to 20 hours and during mitosis the particles are distributed between the daughter cells. Associated with the particles is the high total lipid content of the rabbit liver cell as compared with a rat liver cell, which contains few, if any, lipid-rich particles. This difference in lipid content between the two cells is due primarily to an increase in the triglyceride fraction, in contradistinction to small differences in the polar lipid and sterol ester fractions. The lipid-rich particles have been isolated and found to contain 90 per cent triglyceride on a dry weight basis. The "genetic" factors responsible for the high concentration of lipid-rich particles and triglycerides in the rabbit liver cell require for their full expression one or more factors which are present in much higher effective concentrations in rabbit serum than in horse serum. The hypothesis is advanced that the lipid-rich particles represent a normal state of the non-structural cell lipid. A procedure is described for the quantitative isolation of the lipid of cultured cells.  相似文献   
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