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81.
BACKGROUND: Acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD) are associated with increased airflow Limitation, hyperinflation and respiratory muscle fatigue. It is unclear, whether patients are able to perform adequate inhalations through various inhalation devices with different orfices during an exacerbation. The aim of this study was to examine the evolution of inhalation profiles of patients inhaling through Diskus, Turbuhaler, pressurized metered dose inhaler (pMDI) and Volumatic and consequently the appropriateness of using the various devices during an exacerbation. MEASUREMENTS: 15 hospitalized patients participated in this randomized comparison of inhalation profiles through the four placebo-devices. For each device, triplicate inhalation profiles were recorded during day 1-9 of admission and in stable phase (day 50). RESULTS: The mean percentage of patients performing optimum inhalation profiles was 100% for Diskus, 60% for Turbuhaler, 14% for pMDI and 87% for Volumatic over the interval of day 1-9 and day 50. Patients with an inspiratory muscle strength (MIP) of less than 6kPa were generally unable to generate the optimum flow through the Turbuhaler (>60 l/min). CONCLUSION: The Diskus and Volumatic can be used effectively in the acute phase of an exacerbation of asthma or COPD. The Turbuhaler could be optimally used after the fifth day of convalescence. The pMDI is rather unsuitable during an exacerbation. 相似文献
82.
Jennes W Sawadogo S Koblavi-Dème S Vuylsteke B Maurice C Roels TH Chorba T Nkengasong JN Kestens L 《AIDS research and human retroviruses》2002,18(3):171-177
The role of beta-chemokines in controlling HIV replication in vivo is still controversial. Therefore, the association between HIV-1 plasma viral load and the capacity of CD4(+) and CD8(+) T cells to produce beta-chemokines was studied in 28 antiretroviral drug-na?ve HIV-1-infected female sex workers in Abidjan, C?te d'Ivoire. Percentages of beta-chemokine-positive T cells were measured in peripheral blood mononuclear cells by flow cytometry after intracellular staining for RANTES (regulated on activation, normal T expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta. HIV-1-infected subjects had higher percentages of MIP-1alpha- and MIP-1beta-positive CD4(+) and CD8(+) T cells (p < 0.02) and of RANTES-positive CD8(+) T cells (p = 0.054) than uninfected controls. Percentages of RANTES- and MIP-1beta-positive CD8(+) T cells correlated directly with HIV-1 plasma viral load (p < 0.02). Percentages of beta-chemokine-positive CD4(+) and CD8(+) T cells correlated directly with percentages of HLA-DR-positive T cells (p < 0.02) and inversely (except RANTES in CD4(+) T cells) with absolute numbers of CD4(+) T cells (p < 0.05) in peripheral blood. These data indicate that increased percentages of beta-chemokine-producing T cells in HIV-1-infected subjects correlate with disease progression and are a sign of viremia-driven chronic T cell activation. 相似文献
83.
Matrix metalloproteinases and atrial remodeling in patients with mitral valve disease and atrial fibrillation 总被引:2,自引:0,他引:2
Anné W Willems R Roskams T Sergeant P Herijgers P Holemans P Ector H Heidbüchel H 《Cardiovascular research》2005,67(4):655-666
BACKGROUND: Atrial fibrillation (AF) is associated with extracellular matrix remodeling involving atrial fibrosis and atrial dilatation. Angiotensin II mediated pathways and matrix metalloproteinases (MMPs) have been implicated in these processes. Our aim was to study atrial structural remodeling and the expression of the angiotensin receptor subtypes and MMPs and their inhibitors (TIMPs) in patients with mitral valve disease with and without AF. METHODS AND RESULTS: Biopsies from right and left atrial appendages (RA and LA) were taken from patients undergoing CABG (n=9, all in sinus rhythm (SR)) or mitral valve surgery (MVS; n=19; 9 with permanent AF and 10 in SR). Patients with MVS and AF had significantly larger atria (versus MVS and SR: p=0.02; versus CABG: p<0.01). The MVS patients had significantly more fibrosis than the control CABG group. Fibrosis was increased in both the AF and SR MVS groups in the LA, but only in the MVS-AF group in the RA. These AF patients had significantly more tricuspid regurgitation than SR patients. MMP-1 was down-regulated in LA of MVS patients (p=0.02) independent of the underlying rhythm (SR or AF; p=0.95). In RA biopsies, MMP-1 was down-regulated only in the MVS and AF group. MMP-9 was down-regulated in the MVS patients compared to CABG both in the RA and LA, and without a difference between the SR and AF groups. Protein expression of AT-1, AT-2, MMP-2, TIMP-1, -2 and -4, TNF-alpha, and TNF-alpha-converting enzyme did not differ significantly between the 3 groups. CONCLUSIONS: Concordant changes between MMP-expression and fibrosis during mitral valve disease, both in LA and RA, suggest involvement of MMPs in structural atrial remodeling. AF itself did not contribute to altered fibrosis or MMP-expression in the LA. The association between AF and RA changes may be precipitated by greater hemodynamic load due to tricuspid regurgitation in these patients. 相似文献
84.
Wim Huysmans MD Werner Budts MD PhD 《Catheterization and cardiovascular interventions》2008,72(2):286-288
We report a remarkable case of right atrial rupture, 3 years after transcatheter closure of a secundum atrial septal defect, and 7 months after permanent transvenous two‐chamber pacemaker implantation. The etiology of the rupture remains unclear, but the presence of the two intracardiac devices is probably not coincidental. © 2008 Wiley‐Liss, Inc. 相似文献
85.
Robert W. A. M. Kuijpers John N. van den Anker Wim Baerts Albert E. G. Kr. von dem Borne 《British journal of haematology》1994,87(3):576-579
We report a family with a neonate who was severely damaged by intracranial haemorrhages. These probably occurred before the 20th week of gestation. The neonate had a moderate thrombocytopenia. In the maternal serum anti-HPA-1b and anti-HPA-2a alloantibodies were detected. Third-generation assays were applied to identify the alloantibodies. No other cause for the bleeding was found. Probably the combination of anti-HPA-1b and anti-HPA-2a alloantibodies, directed against the platelet fibrinogen receptor and the von Willebrand receptor, respectively, induced a thrombocytopenia and a thrombocytopathy. 相似文献
86.
Jennes W Sawadogo S Koblavi-Dème S Vuylsteke B Maurice C Roels TH Chorba T Nkengasong JN Kestens L 《The Journal of infectious diseases》2003,187(2):206-214
Cellular factors that may protect against human immunodeficiency virus (HIV) infection were investigated in 27 HIV-exposed seronegative (ESN) female sex workers (FSWs) and 27 HIV-seronegative female blood donors. Compared with blood donors, ESN FSWs had significantly decreased expression levels of C-X-C chemokine receptor 4 (CXCR4), but not of C-C chemokine receptor 5, on both memory (P<.001) and naive (P=.041) CD4(+) T cells. CXCR4 down-regulation was associated with prolonged duration of commercial sex work by ESN FSWs. CD38 expression on CD8(+) T cells was significantly increased among ESN FSWs, compared with that among blood donors (P=.017). There were no differences in HLA-DR and CD62L expression between blood donors and ESN FSWs. Proportions of T cells producing the beta-chemokines RANTES (regulated on activation, normally T cell-expressed and -secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta or the cytokines interleukin (IL)-2, IL-4, interferon-gamma, and tumor necrosis factor-alpha, were similar in the 2 groups. These data indicate that ESN FSWs differ from HIV-seronegative female blood donors with respect to immunological factors that have no clear protective potential against HIV transmission. 相似文献
87.
Kerstens MN van der Kleij FG Boonstra AH Sluiter WJ Koerts J Navis G Dullaart RP 《The Journal of clinical endocrinology and metabolism》2003,88(9):4180-4185
We studied cortisol metabolism together with insulin sensitivity [homeostatic model assessment (HOMA)] and renal hemodynamics in 19 salt-resistant (sr) and nine salt-sensitive (ss) normotensive subjects after a low- and high-salt diet. Results are described as high- vs. low-salt diet. Sum of urinary cortisol metabolite excretion (sum(metabolites)) increased in sr subjects (3.8 +/- 1.6 vs. 3.1 +/- 1.1 microg/min per square meter, P < 0.05) and decreased in ss subjects (2.3 +/- 1.0 vs. 2.9 +/- 1.1 microg/min per square meter, P < 0.05). Plasma 0830 h cortisol decreased in sr subjects but did not change significantly in ss subjects. In all subjects, the absolute blood pressure change correlated negatively with the percentage change in sum(metabolites) (P < 0.05) and positively with the percentage change in renal vascular resistance (P < 0.05). Sum(metabolites) during high-salt diet correlated negatively with the percentage changes in plasma 0830 h cortisol (P < 0.05) and renal vascular resistance (P = 0.05). HOMA did not change in either group, but the percentage change in HOMA correlated positively with the percentage change in plasma cortisol (P = 0.001) and negatively with the percentage change in sum(metabolites) (P < 0.01). Parameters of 11 beta-hydroxysteroid dehydrogenase activity were not different between groups and did not change. In conclusion, these data suggest that cortisol elimination is affected differently after salt loading in sr and ss subjects. Changes in circulating cortisol might contribute to individual sodium-induced alterations in insulin sensitivity. 相似文献
88.
Aalheiur Dra Albertsdttir Wim Van Gansbeke Gilles Coppieters Kyzylkul Balgimbekova Peter Van Eenoo Michael Polet 《Drug testing and analysis》2020,12(8):1041-1053
Sulfated metabolites have been shown to have potential as long‐term markers of anabolic–androgenic steroid (AAS) abuse. In 2019, the compatibility of gas chromatography–mass spectrometry (GC–MS) with non‐hydrolysed sulfated steroids was demonstrated, and this approach allowed the incorporation of these compounds in a broad GC–MS initial testing procedure at a later stage. However, research is needed to identify which are beneficial. In this study, a search for new long‐term metabolites of two popular AAS, metenolone and drostanolone, was undertaken through two excretion studies each. The excretion samples were analysed using GC–chemical ionization–triple quadrupole MS (GC–CI–MS/MS) after the application of three separate sample preparation methodologies (i.e. hydrolysis with Escherichia coli–derived β‐glucuronidase, Helix pomatia–derived β‐glucuronidase/arylsulfatase and non‐hydrolysed sulfated steroids). For metenolone, a non‐hydrolysed sulfated metabolite, 1β‐methyl‐5α‐androstan‐17‐one‐3ζ‐sulfate, was documented for the first time to provide the longest detection time of up to 17 days. This metabolite increased the detection time by nearly a factor of 2 in comparison with the currently monitored markers for metenolone in a routine doping control initial testing procedure. In the second excretion study, it prolonged the detection window by 25%. In the case of drostanolone, the non‐hydrolysed sulfated metabolite with the longest detection time was the sulfated analogue of the main drostanolone metabolite (3α‐hydroxy‐2α‐methyl‐5α‐androstan‐17‐one) with a detection time of up to 24 days. However, the currently monitored main drostanolone metabolite in routine doping control, after hydrolysis of the glucuronide with E.coli, remained superior in detection time (i.e. up to 29 days). 相似文献
89.
Simone van Binnendijk Marieke B. Snijder Aart H. Schene Eske M. Derks Wim van den Brink 《Journal of dual diagnosis》2020,16(3):271-284
AbstractObjective: Ethnic minorities report different levels of drinking and smoking and higher rates of depression compared to native populations. In this study we aimed to investigate in six ethnic groups whether tobacco and alcohol use were associated with depressive symptoms, which are more prevalent in ethnic minorities.Methods: Cross-sectional data from the multi-ethnic Healthy Life in an Urban Setting (HELIUS) study sample (N?=?22,471) was used, comprising 4,580 native Dutch participants which were compared with participants from five ethnic minority groups (3,259 South Asian Surinamese, 4,292 African Surinamese, 2,262 Ghanaian, 3,891 Turkish, and 4,187 Moroccan).Results: Alcohol misuse was positively associated with depressed mood in all ethnic groups except for the Dutch and the Ghanaians. Nicotine dependence was positively associated with depressed mood in all ethnic groups except for the Ghanaian group.Conclusions: Alcohol misuse and nicotine dependence were significantly associated with depressed mood in most but not all ethnic groups and especially in men. However, across all groups the contribution of alcohol misuse and nicotine dependence to depressed mood was small. Prospective multi-ethnic studies should confirm whether the relations are causal and elucidate their direction. 相似文献
90.
Louis De Muynck Sarah Herdewyn Sander Beel Wendy Scheveneels Ludo Van Den Bosch Wim Robberecht Philip Van Damme 《Neurobiology of aging》2013
Progranulin (PGRN) is a growth factor involved in wound healing, inflammation, tumor growth, and neurodegeneration. Mutations in the gene encoding PGRN give rise to shortage of PGRN and cause familial frontotemporal lobar degeneration. PGRN exerts neurotrophic functions and binding of PGRN to the membrane receptor sortilin (SORT1) mediates the endocytosis of PGRN. SORT1-mediated uptake plays an important role in the regulation of extracellular PGRN levels. We studied the role of SORT1 in PGRN-mediated neuroprotection in vitro and in vivo. The survival-enhancing effect of PGRN seemed to be dependent on the granulin E (GRN E) domain. Pharmacologic inhibition of the GRN E–SORT1 interaction or deletion of the SORT1 binding site of GRN E did not abolish its neurotrophic function. In addition, the in vivo phenotype of PGRN knockdown in zebrafish embryos was not phenocopied by SORT1 knockdown. These results suggest that GRN E mediates the neurotrophic properties of PGRN and that binding to SORT1 is not required for this effect. 相似文献