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91.
Xiaohong Zheng Tony D'Amore Inge Russell Graham G. Stewart 《Journal of industrial microbiology & biotechnology》1994,13(3):159-166
Summary Maltotriose transport was studied in two brewer's yeast strains, an ale strain 3001 and a lager strain 3021, using laboratory-synthesized14C-maltotriose. The maltotriose transport systems preferred a lower pH (pH 4.3) to a higher pH (pH 6.6). Two maltotriose transport affinity systems have been indentified. The high affinity system hasK
m values of 1.3 mM for strain 3021 and 1.4 mM for strain 3001. The low affinity competitively inhibited by maltose and glucose withK
i values of 58 mM and 177 mM. respectively, for strain 3021, and 55 mM and 147 mM, respectively, for strain 3001. Cells grown in maltotriose and maltose had higher maltotriose and maltose transport rates, and cells grown in glucose had lower maltortriose and maltose transport rates. Early-logarithmic phase cells transported glucose faster than either maltose or maltotriose. Cells harvested later in the growth phase had increased maltotriose and maltose transport activity. Neither strain exhibited significant differences with respect to maltose and maltotriose transport activity. 相似文献
92.
Urheim S Rabben SI Skulstad H Lyseggen E Ihlen H Smiseth OA 《American journal of physiology. Heart and circulatory physiology》2005,288(5):H2375-H2380
There is a need for better methods to quantify regional myocardial function. In the present study, we investigated the feasibility of quantifying regional function in terms of a segmental myocardial work index as derived from strain Doppler echocardiography (SDE) and invasive pressure. In 10 anesthetized dogs, we measured left ventricular (LV) pressure by micromanometer and myocardial longitudinal strains by SDE and sonomicrometry. The regional myocardial work index (RMWI) was calculated as the area of the pressure-strain loop. As a reference method for strain, we used sonomicrometry. By convention, the loop area was assigned a positive sign when the pressure-strain coordinates rotated counterclockwise. Measurements were done at baseline and during volume loading and left anterior descending coronary artery (LAD) occlusion, respectively. There was a good correlation between RMWI calculated from strain by SDE and strain by sonomicrometry (y = 0.73x + 0.21, r = 0.82, P < 0.01). Volume loading caused an increase in RMWI from 1.3 +/- 0.2 to 2.2 +/- 0.1 kJ/m3 (P < 0.05) by SDE and from 1.5 +/- 0.3 to 2.7 +/- 0.3 kJ/m3 (P = 0.066) by sonomicrometry. Short-term ischemia (1 min) caused a decrease in RMWI from 1.3 +/- 0.2 to 0.3 +/- 0.04 kJ/m3 (P < 0.05) and from 1.3 +/- 0.3 to 0.5 +/- 0.2 kJ/m3 (P < 0.05) by SDE and sonomicrometry, respectively. In the nonischemic ventricle and during short-term ischemia, the pressure-strain loops rotated counterclockwise, consistent with actively contracting segments. Long-term ischemia (3 h), however, caused the pressure-strain loop to rotate clockwise, consistent with entirely passive segments, and the loop areas became negative, -0.2 +/- 0.1 and -0.1 +/- 0.03 kJ/m3 (P < 0.05) by SDE and sonomicrometry, respectively. A RMWI can be estimated by SDE in combination with LV pressure. Furthermore, the orientation of the loop can be used to assess whether the segment is active or passive. 相似文献
93.
Inge W. Nilsen Kersti
verb Ragnar L. Olsen 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2001,129(4)
Sequence analysis of short fragments resulting from trypsin digestion of the thermolabile shrimp alkaline phosphatase (SAP) from Northern shrimp Pandalus borealis formed the basis for amplification of its encoding cDNA. The predicted protein sequence was recognized as containing the consensus alkaline phosphatase motif comprising the active site of this protein family. Protein sequence homology searches identified several eukaryote alkaline phosphatases with which the 475-amino acid SAP polypeptide revealed shares 45% amino acid sequence identity. Residues for potential metal binding seem to be conserved in these proteins. The predicted 54-kDa molecular mass of SAP is smaller than previously reported, but is consistent with our recent SDS-PAGE analysis of the native protein. Compared to its homologs, the shrimp enzyme has a surplus of negatively charged amino acids, while the relative number of prolines is lower and the frequency of aromatic residues is higher than in mesophilic counterparts. 相似文献
94.
Background
Insulin resistance and type 2 diabetes are more prevalent in people of South Asian ethnicity than in people of Western European origin. To investigate the source of these differences, we compared insulin sensitivity, insulin secretion, glucose and lipid metabolism in South Asian and Nordic subjects with type 2 diabetes.Methods
Forty-three Nordic and 19 South Asian subjects with type 2 diabetes were examined with intra-venous glucose tolerance test, euglycemic clamp including measurement of endogenous glucose production, indirect calorimetry measuring glucose and lipid oxidation, and dual x-ray absorptiometry measuring body composition.Results
Despite younger mean ± SD age (49.7±9.4 vs 58.3±8.3 years, p = 0.001), subjects of South Asian ethnicity had the same diabetes duration (9.3±5.5 vs 9.6±7.0 years, p = 0.86), significantly higher median [inter-quartile range] HbA1c (8.5 [1.6] vs 7.3 [1.6] %, p = 0.024) and lower BMI (28.7±4.0 vs 33.2±4.7 kg/m2, p<0.001). The South Asian group exhibited significantly higher basal endogenous glucose production (19.1 [9.1] vs 14.4 [6.8] µmol/kgFFM⋅min, p = 0.003). There were no significant differences between the groups in total glucose disposal (39.1±20.4 vs 39.2±17.6 µmol/kgFFM⋅min, p = 0.99) or first phase insulin secretion (AUC0–8 min: 220 [302] vs 124 [275] pM, p = 0.35). In South Asian subjects there was a tendency towards positive correlations between endogenous glucose production and resting and clamp energy expenditure.Conclusions
Subjects of South Asian ethnicity with type 2 diabetes, despite being younger and leaner, had higher basal endogenous glucose production, indicating higher hepatic insulin resistance, and a trend towards higher use of carbohydrates as fasting energy substrate compared to Nordic subjects. These findings may contribute to the understanding of the observed differences in prevalence of type 2 diabetes between the ethnic groups. 相似文献95.
Jan Michiels Inge D'hooghe Christel Verreth Heidi Pelemans Jos Vanderleyden 《Archives of microbiology》1994,161(5):404-408
We report the isolation, mutational analysis and the nucleotide sequence of the Rhizobium leguminosarum bv. phaseoli nifA gene. Comparison of the deduced amino acid sequence with other NifA sequences indicated the presence of the conserved central activator and the C-terminal DNA-binding domains. Nodules elicited by a R. leguminosarum bv. phaseoli nifA mutant were symbiotically ineffective. The expression of a nifA-gusA fusion was shown to be independent on the oxygen status of the cell. We cloned the three nifH copies of R. leguminosarum bv. phaseoli and determined the nucleotide sequence of their promoter regions. The expression of nifH-gusA fusions is induced under microaerobic conditions and is dependent on the presence of NifA.Abbreviations bp
base pair(s)
- kb
kilobase(s)
- ORF
open reading frame 相似文献
96.
De Vos A Sermon K Van de Velde H Joris H Vandervorst M Lissens W De Paepe A Liebaers I Van Steirteghem A 《Human genetics》2000,106(6):605-613
Osteogenesis imperfecta (OI) is an autosomal dominant genetic disorder characterized by the presence of brittle bones and decreased bone mass (osteopenia), as a result of mutations in the genes that encode the chains of type I collagen, the major protein of bone. The clinical features of the disease range from death in the perinatal period to normal life span with minimal increase in fractures. The present report describes two polymerase chain reaction (PCR)-based assays allowing preimplantation genetic diagnosis (PGD) on the one hand for OI type I, the mildest form, and on the other hand for OI type IV, which is intermediate in severity between OI type I and OI type III. In the couple referred for PGD for OI type I, the female partner carried a 1-bp deletion in exon 43 of the COL1A1 gene, resulting in a premature stop codon in exon 46. The synthesis of too little type I procollagen results from such a non-functional or COL1A1 null allele. In the other couple, referred for PGD for OI type IV, the male partner carried a G to A substitution in exon 19 of the COL1A2 gene, which results in an abnormal gene product due to an alphaGly247 (GGT) to Ser (AGT) substitution (G247S). Both mutations result in the loss of a specific restriction enzyme recognition site and can therefore be detected by PCR amplification followed by restriction fragment analysis. PCR amplification of genomic DNA of the parents-to-be with one of the two primers fluorescently labelled, followed by automated laser fluorescence (ALF) gel electrophoresis of the amplified and restricted fragments, allowed a distinction between the healthy and affected genotypes. PCR on single Epstein-Barr-virus (EBV)-transformed lymphoblasts resulted in acceptable amplification efficiencies (87% and 85% for OI type I and OI type IV respectively) and the allele drop-out (ADO) rate was assessed at 11.5% and 11.1% for OI type I and OI type IV respectively. With research blastomeres, 100% amplification rates were obtained and no contamination was observed in the blank controls, which validated the tests for clinical application. Embryos obtained after intracytoplasmic sperm injection (ICSI) were evaluated for the presence of the normal genotype of the non-affected parent. For OI type I, two frozen-thawed ICSI-PGD cycles and two fresh ICSI-PGD cycles were carried out for the same couple. The transfer of two unaffected embryos in the last cycle resulted in a twin pregnancy. A twin pregnancy was also achieved in one clinical ICSI-PGD cycle for OI type IV. 相似文献
97.
Filamentous fungi are capable of secreting relatively large amounts of heterologous recombinant proteins. Recombinant human glycoproteins expressed in this system, however, carry only carbohydrates of the oligomannose type limiting their potential use in humans. One approach to the problem is genetic engineering of the fungal host to permit production of complex and hybrid N-glycans. UDP-GlcNAc:3-d-mannoside -1,2-N-acetylglucosaminyltransferase I (GnT I) is essential for the conversion of oligomannose to hybrid and complex N-glycans in higher eukaryotic cells. Since GnT I is not produced by fungi, we have introduced into the genome ofAspergillus nidulans the gene encoding full-length rabbit GnT I and demonstrated the expression of GnT I enzyme activity at levels appreciably higher than occurs in most mammalian tissues. All the GnT I activity in theAspergillus transformants remains intracellular suggesting that the rabbit trans-membrane sequence may be capable of targeting GnT I to the fungal Golgi apparatus.Abbreviations CM
complete medium
- Gal-T
UDP-Gal:GlcNAc -1,4-galactosyltransferase (EC 2.4.1.38/90)
- GnT I
UDP-GlcNAc:3-d-mannoside -1,2-N-acetylglucosaminyltransferase I (EC 2.4.1.101)
- HPLC
high performance liquid chromatography
- M3-octyl
Man1-6[Man1-3]Man-octyl
- PAGE
polyacrylamide gel electrophoresis
- MES
2-(N-morpholino)ethane sulfonate
- PCR
polymerase chain reaction
- PEG
polyethylene glycol
- PMSF
phenyl methyl sulfonyl fluoride
- SDS
sodium dodecyl sulfate
- SSC (1×)
0.15m NaCl/0.015m sodium citrate (pH 7.0)
- STC
1.2m sorbitol, 100mm Tris-HCl, pH 7.4, and 10mm CaCl2
- STET
0.1m NaCl, 10mm Tris-HCl, pH 8.0, 1mm EDTA, pH 8.0, 5% Triton-X-100
Deceased. This paper is dedicated to the memory of Lorne S. Reid. 相似文献
98.
Junker N Andersen MH Wenandy L Dombernowsky SL Kiss K Sørensen CH Therkildsen MH Von Buchwald C Andersen E Straten PT Svane IM 《Cytotherapy》2011,13(7):822-834
Background aimsAdoptive transfer of tumor-infiltrating lymphocytes (TIL) has proven effective in metastatic melanoma and should therefore be explored in other types of cancer. The aim of this study was to examine the feasibility of potentially expanding clinically relevant quantities of tumor-specific T-cell cultures from TIL from patients with head and neck squamous cell carcinoma (HNSCC) using a more rapid expansion procedure compared with previous HNSCC studies.MethodsIn a two-step expansion process, initially TIL bulk cultures were established from primary and recurrent HNSCC tumors in high-dose interleukin (IL)-2. Secondly, selected bulk cultures were rapidly expanded using anti-CD3 antibody, feeder cells and high-dose IL-2. T-cell subsets were phenotypically characterized using flow cytometry. T-cell receptor (TCR) clonotype mapping was applied to examine clonotype dynamics during culture. Interferon (INF)-γ detection by Elispot and Cr51 release assay determined the specificity and functional capacity of selected TIL pre- and post-rapid expansion.ResultsTIL bulk cultures were expanded in 80% of the patients included, showing tumor specificity in 60% of the patients. Rapid expansions generated up to 3500-fold expansion of selected TIL cultures within 17 days. The cultures mainly consisted of T-effector memory cells, with varying distributions of CD8+ and CD4+ subtypes both among cultures and patients. TCR clonotype mapping demonstrated oligoclonal expanded cultures, ranging from approximately 10 to 30 T-cell clonotypes. TIL from large-scale rapid expansions maintained functional capacity, and contained tumor-specific T cells.ConclusionThe procedure is feasible for expansion of TIL from HNSCC, ensuring clinically relevant expansion folds within 7 weeks. The cell culture kinetics and phenotypes of the TIL resemble previously published results on TIL from melanoma, setting the stage for clinical testing of this promising treatment strategy for patients with HNSCC. 相似文献
99.
Vaccination with p53-peptide–pulsed dendritic cells,of patients with advanced breast cancer: report from a phase I study 总被引:3,自引:0,他引:3
Svane IM Pedersen AE Johnsen HE Nielsen D Kamby C Gaarsdal E Nikolajsen K Buus S Claesson MH 《Cancer immunology, immunotherapy : CII》2004,53(7):633-641
Peptides derived from over-expressed p53 protein are presented by class I MHC molecules and may act as tumour-associated epitopes. Due to the diversity of p53 mutations, immunogenic peptides representing wild-type sequences are preferable as a basis for a broad-spectrum p53-targeting cancer vaccine. Our preclinical studies have shown that wild-type p53-derived HLA-A2–binding peptides are able to activate human T cells and that the generated effector T cells are cytotoxic to human HLA-A2+, p53+ tumour cells. In this phase I pilot study, the toxicity and efficacy of autologous dendritic cells (DCs) loaded with a cocktail of three wild-type and three modified p53 peptides are being analysed in six HLA-A2+ patients with progressive advanced breast cancer. Vaccinations were well tolerated and no toxicity was observed. Disease stabilisation was seen in two of six patients, one patient had a transient regression of a single lymph node and one had a mixed response. ELISpot analyses showed that the p53-peptide–loaded DCs were able to induce specific T-cell responses against modified and unmodified p53 peptides in three patients, including two of the patients with a possible clinical benefit from the treatment. In conclusion, the strategy for p53-DC vaccination seems safe and without toxicity. Furthermore, indications of both immunologic and clinical effect were found in heavily pretreated patients with advanced breast cancer. An independent clinical effect of repeated administration of DCs and IL-2 can not of course be excluded; further studies are necessary to answer these questions. 相似文献
100.
Satoh M Bjerkås I Haugarvoll E Chan EK Szabo NJ Jirillo E Poppe TT Sveier H Tørud B Koppang EO 《Fish & shellfish immunology》2011,30(4-5):1080-1086
The introduction of oil-adjuvanted vaccines in salmon aquaculture made large-scale production feasible by reducing the impact of infections. Vaccines given intraperitoneally (ip) contain oil adjuvant such as mineral oil. However, in rodents, a single ip injection of adjuvant hydrocarbon oil induces lupus-like systemic autoimmune syndrome. We have recently reported that autoimmune disease in farmed salmon, characterized by production of various autoantibodies, immune complex glomerulonephritis, liver thrombosis, and spinal deformity, are previously unrecognized side effects of vaccination. In the present study, we examined whether vaccination-induced autoantibody production in farmed Atlantic salmon is a mere result of polyclonal B-cell activation. Sera were collected from 205 vaccinated and unvaccinated Atlantic salmon (experimental, 7 farms) and wild salmon. Total IgM levels and autoantibodies to salmon blood cell (SBC) extract in sera were measured by ELISA and the relationship between hypergammaglobulinemia and autoantibody production was analyzed. Comparison of endpoint titers vs levels/units using a single dilution of sera in detection of autoantibodies to SBC showed near perfect correlation, justifying the use of the latter for screening. Both total IgM and anti-SBC antibodies are increased in vaccinated salmon compared with unvaccinated controls, however, they do not always correlate well when compared between groups or between individuals, suggesting the involvement of antigen-specific mechanisms in the production of anti-SBC autoantibodies. The primary considerations of successful vaccine for aquaculture are cost-effectiveness and safety. Vaccination-induced autoimmunity in farmed Atlantic salmon may have consequences on future vaccine development and salmon farming strategy. Evaluation for polyclonal hypergamamglobulinemia and autoimmunity should be included as an important trait when vaccine efficacy and safety are evaluated in future. 相似文献