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1.
Imre W.K. Kouw Bart B.L. Groen Joey S.J. Smeets Irene Fleur Kramer Janneau M.X. van Kranenburg Rachél Nilwik Jan A.P. Geurts René H.M. ten Broeke Martijn Poeze Luc J.C. van Loon Lex B. Verdijk 《Journal of the American Medical Directors Association》2019,20(1):35-42
Objectives
Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.Design and participants
Twenty-six older patients (75 ± 1 years) undergoing elective total hip arthroplasty participated in this observational study.Measurements
On hospital admission and on the day of discharge, computed tomographic (CT) scans were performed to assess muscle cross-sectional area (CSA) of both legs. During surgery and on the day of hospital discharge, a skeletal muscle biopsy was taken from the m. vastus lateralis of the operated leg to assess muscle fiber type–specific CSA.Results
An average of 5.6 ± 0.3 days of hospitalization resulted in a significant decline in quadriceps (?3.4% ± 1.0%) and thigh muscle CSA (?4.2% ± 1.1%) in the nonoperated leg (P < .05). Edema resulted in a 10.3% ± 1.7% increase in leg CSA in the operated leg (P < .05). At hospital admission, muscle fiber CSA was smaller in the type II vs type I fibers (3326 ± 253 μm2 vs 4075 ± 279 μm2, respectively; P < .05). During hospitalization, type I and II muscle fiber CSA tended to increase, likely due to edema in the operated leg (P = .10).Conclusions
Six days of hospitalization following elective total hip arthroplasty leads to substantial leg muscle atrophy in older patients. Effective intervention strategies are warranted to prevent the loss of muscle mass induced by short periods of muscle disuse during hospitalization. 相似文献2.
B. C. Beaudette-Zlatanova B. Whalen D. Zipris H. Yagita J. Rozing H. Groen C. D. Benjamin T. Hunig H. A. Drexhage M. J. Ansari J. Leif J. P. Mordes D. L. Greiner M. H. Sayegh A. A. Rossini 《American journal of transplantation》2006,6(5P1):894-902
Costimulatory signals regulate T-cell activation. To investigate the role of costimulation in autoimmunity and transplantation, we studied the BB rat model of type 1 diabetes. Diabetes-prone BB (BBDP) rats spontaneously develop disease when 55–120 days of age. We observed that two anti-CD28 monoclonal antibodies (mAb) with different functional activities completely prevented diabetes in BBDP rats. Anti-CD154 mAb delayed diabetes, whereas treatment with CTLA4-Ig or anti-CD80 mAb accelerated disease. Anti-CD86 or anti-CD134L mAbs had no effect. Diabetes resistant BB (BBDR) rats are disease-free, but >95% of them develop diabetes after treatment with polyinosinic-polycytidylic acid and an mAb that depletes Treg cells. In the induced BBDR model, anti-CD154 mAb delayed onset of diabetes, whereas CTLA4-Ig, anti-CD134L or either of the anti-CD28 mAbs had little or no effect. In contrast, blockade of the CD134-CD134L pathway was highly effective for preventing autoimmune recurrence against syngeneic islet grafts in diabetic BBDR hosts. Blockade of the CD40-CD154 pathway was also effective, but less so. These data suggest that the effectiveness of costimulation blockade in the treatment of type 1 diabetes is dependent on both the costimulatory pathway targeted and the mechanism of induction, stage, intensity and duration of the pathogenic process. 相似文献
3.
Surgical resection for small cell carcinoma of the lung: a retrospective study. 总被引:1,自引:0,他引:1 下载免费PDF全文
BACKGROUND--A retrospective review was undertaken of the survival of 21 patients with histologically proven small cell carcinoma of the lung resected between 1977 and 1991. METHODS--Twenty one patients (20 men) of median age 60 (range 44-73) years underwent surgical resection. Patients were subjected to standard clinical staging procedures. Preoperative diagnosis was small cell carcinoma of the lung in 13, non-small cell lung cancer in one, and uncertain in seven patients. Clinical staging was stage I disease in 11 and stage II in 10 patients. RESULTS--Resection included pneumonectomy in 12 cases, lobectomy in eight, and one wedge resection. Resection was complete in 16 patients. Postoperative histopathological examination confirmed small cell carcinoma of the lung in 19 specimens and mixed small cell and non-small cell carcinoma of the lung in two. Pathological staging was stage I in 11, stage II in three, and stage III in seven patients. The final pathological diagnosis of the resected specimens (n = 18) was atypical carcinoid in one, pure small cell carcinoma of the lung in 15, and mixed small cell and non-small cell carcinoma of the lung in two patients. Fourteen patients also received chemotherapy and 10 received prophylactic cranial irradiation postoperatively. Excluding the patient with a final diagnosis of atypical carcinoid, the median survival (n = 20) was 29 months (range two to 133+). Median survival for patients with pathological stage I and II disease (n = 13) was 40 months (range nine to 133+) and for patients with pathological stage III disease (n = 7) 20 months (range two to 116+). The median disease free survival was 23 months. Eleven patients relapsed between two and 101 months. There was no advantage for those patients who received postoperative chemotherapy. CONCLUSION--Curative resection offers the best chance for long term survival in patients with small cell carcinoma of the lung with very limited stage disease. 相似文献
4.
J Groen J Dalrymple S Fisher-Hoch J G Jordans J P Clement A D Osterhaus 《Journal of medical virology》1992,37(4):283-287
An enzyme-linked immunosorbent assay (ELISA) was developed for the quantification of serum antibodies against group-specific epitopes of the glycoproteins (G1, G2) and nucleoprotein (NP) of the genus Hantavirus. This assay was used to study the kinetics of the development of serum antibodies after natural infection with Puumala-like virus in humans. To this end a panel of 34 serum samples collected from individuals at different times after natural infection was tested by the ELISA. The samples were also tested for specific IgM and IgG levels against Puumala-like virus, which provided confirmatory data about the presumed timing of infection. It was shown that serum antibodies against the G1 epitope were present in the acute and early convalescent period just before antibodies to the NP epitope could be demonstrated. In contrast, antibodies to two G2 epitopes were present not earlier than in the convalescent and late convalescent period. Since all these categories of antibodies seem to persist for long periods, antibodies against the G1 epitope and the NP epitope may be of specific diagnostic value. Furthermore, levels of G1-specific antibodies and antibodies to either NP or G2 may allow estimation of the time elapsed following initial infection. 相似文献
5.
Class III P-glycoproteins mediate the formation of lipoprotein X in the mouse. 总被引:2,自引:0,他引:2 下载免费PDF全文
R P Elferink R Ottenhoff J van Marle C M Frijters A J Smith A K Groen 《The Journal of clinical investigation》1998,102(9):1749-1757
Cholestasis is associated with hypercholesterolemia and appearance of the abnormal lipoprotein X (LpX) in plasma. Using mice with a disrupted Mdr2 gene, we tested the hypothesis that LpX originates as a biliary lipid vesicle. Mdr2-deficient mice lack Mdr2 P-glycoprotein, the canalicular translocator for phosphatidylcholine, and secrete virtually no phospholipid and cholesterol in bile. Bile duct ligation of Mdr2(+)/+ mice induced a dramatic increase in the plasma cholesterol and phospholipid concentration. Agarose electrophoresis, density gradient ultracentrifugation, gel permeation, and electron microscopy revealed that the majority of phospholipid and cholesterol was present as LpX, a 40-100 nm vesicle with an aqueous lumen. In contrast, the plasma cholesterol and phospholipid concentration in Mdr2(-)/- mice decreased upon bile duct ligation, and plasma fractionation revealed a complete absence of LpX. In mice with various expression levels of Mdr2 or MDR3, the human homolog of Mdr2, we observed that the plasma level of cholesterol and phospholipid during cholestasis correlated very closely with the expression level of these canalicular P-glycoproteins. These data demonstrate that during cholestasis there is a quantitative shift of lipid secretion from bile to the plasma compartment in the form of LpX. The concentration of this lipoprotein is determined by the activity of the canalicular phospholipid translocator. 相似文献
6.
Laukkanen T Carr JK Janssens W Liitsola K Gotte D McCutchan FE Op de Coul E Cornelissen M Heyndrickx L van der Groen G Salminen MO 《Virology》2000,269(1):95-104
For reliable classification of HIV-1 strains appropriate reference sequences are needed. The HIV-1 genetic subtype F has a wide geographic spread, causing significant epidemics in South America, Africa, and some regions of Europe. Previously only two full-length sequences of each of the HIV-1 subtype F subclusters F1 and F2 have been described. To extend the knowledge of subtype F variation on a complete genome level, three new virtually full-length F1 sequences were cloned and sequenced, two from Africa and one from South America. Comparison of the new and previously described sequences showed that monophyletic clustering of the subcluster F1 of subtype F is consistent and highly supported in all genome regions. Two additional full-length strains were shown to be mosaics of subtypes F and D. These epidemiologically unrelated F/D sequences showed similar chimeric structure, suggesting that they may represent a previously undescribed circulating recombinant form (CRF). This was supported by partial sequences from three additional unlinked F/D recombinants. Genetic distances in the phylogenetic trees suggest that the recombination event leading to the putative CRF occurred relatively long ago, close to the divergence of the F1 and F2 subclusters. Furthermore, all five F/D recombinants are linked to the Democratic Republic of Congo, suggesting that the original recombination event took place in central Africa. 相似文献
7.
Combination of reverse transcriptase PCR analysis and immunoglobulin M detection on filter paper blood samples allows diagnostic and epidemiological studies of measles 下载免费PDF全文
8.
Development, evaluation, and validation of an oligonucleotide probe hybridization assay to subtype human immunodeficiency virus type 1 circulating recombinant form CRF02_AG 下载免费PDF全文
9.
Masciotra S Rudolph DL van der Groen G Yang C Lal RB 《Clinical and diagnostic laboratory immunology》2000,7(4):706-709
Cross-species transmission has been shown to play an important role in the emergence of human retroviruses. We developed a generic enzyme immunoassay using synthetic peptides from gp41 and C2V3 consensus sequences (human immunodeficiency virus [HIV] type 1 [HIV-1] groups M, O, and N and the homologous region of simian immunodeficiency virus [SIV] strains from chimpanzees [SIVcpz], SIVcpzGAB1 and SIVcpzANT) to detect divergent HIV and SIV. A cocktail of peptides from gp41 and C2V3 (M-O) detected all HIV-1 group M and O sera and showed cross-reactivity with SIVcpz sera. Further, a mixture of C2V3 peptides (GAB1-ANT) failed to detect HIV-1 infections but reacted with all SIVcpz sera, allowing discrimination of SIVcpz from HIV-1 infections. Since most SIVcpz sera cross-reacted with HIV-1 peptides, we next evaluated SIVcpz serum reactivity with rapid tests for HIV-1/2. SIVcpzANT and SIVcpzUS sera reacted with the Sero-strip and Multispot assays. Both tests are sensitive in detecting group M (97 100%, respectively), although Multispot has lower sensitivity for group O detection (67%) than does Sero-strip (100%). The limited volume and time required to perform these assays make them a generic tool for field screening. The env peptide-based assay and rapid tests should allow for the identification of emerging variants of HIV and SIV. 相似文献
10.
Karin Lemmer Oliver Donoso Mantke Hi-Gung Bae Jan Groen Christian Drosten Matthias Niedrig 《Journal of clinical virology》2004,30(4):291-296
BACKGROUND: Increased travelling to countries endemic for dengue fever (DF) demands efficient laboratory diagnostics. Nucleic acid amplification techniques (NAT) are now frequently used for rapid diagnosis of imported viral diseases. Different PCR systems are available. OBJECTIVES: In order to assess the quality of molecular diagnostics of dengue virus infections, an external quality assurance (EQA) in PCR diagnostics was conducted. Study design: A panel of 10 human plasma samples was prepared and spiked with dengue virus types DEN-1 to DEN-4. In addition, a 10-fold dilution series (1:10-1:10(4) ) of DEN-3 virus was included. The panel was pre-tested by nested RT-PCR, in-house real-time PCR, and a commercial real-time PCR kit. The samples were inactivated by gamma irradiation and shipped in freeze dried state. Thirteen laboratories, within the European network for the diagnostics of imported viral diseases (ENIVD) took part using either single-round, nested, or real-time RT-PCR methods. Two laboratories used two methods in parallel, summarising up to 15 comparable results. RESULTS: 33-100% correct results were achieved. All laboratories detected DEN-2 correctly, followed by DEN-1 (14 positive results of 15), DEN-3 (12/15) and DEN-4 (11/15). Testing of the serial dilution revealed low sensitivity in many labs, with results ranging from 33 to 80% of correctly tested samples. CONCLUSION: The EQA gives a feedback of the quality of the RT-PCR system used by each respective laboratory. The different test systems and amplification conditions demonstrate the importance of external quality control measures. 相似文献