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1.
Characterization of the cross-bridge force-generating step using inorganic phosphate and BDM in myofibrils from rabbit skeletal muscles 总被引:10,自引:3,他引:7
The inhibitory effects of inorganic phosphate (Pi ) on isometric force in striated muscle suggest that in the ATPase reaction Pi release is coupled to force generation. Whether Pi release and the power stroke are synchronous events or force is generated by an isomerization of the quaternary complex of actomyosin and ATPase products (AM.ADP.Pi ) prior to the following release of Pi is still controversial. Examination of the dependence of isometric force on [Pi ] in rabbit fast (psoas; 5-15 °C) and slow (soleus; 15-20 °C) myofibrils was used to test the two-step hypothesis of force generation and Pi release. Hyperbolic fits of force-[Pi ] relations obtained in fast and slow myofibrils at 15 °C produced an apparent asymptote as [Pi ]∞ of 0.07 and 0.44 maximal isometric force (i.e. force in the absence of Pi ) in psoas and soleus myofibrils, respectively, with an apparent K d of 4.3 m m in both. In each muscle type, the force-[Pi ] relation was independent of temperature. However, 2,3-butanedione 2-monoxime (BDM) decreased the apparent asymptote of force in both muscle types, as expected from its inhibition of the force-generating isomerization. These data lend strong support to models of cross-bridge action in which force is produced by an isomerization of the AM.ADP.Pi complex immediately preceding the Pi release step. 相似文献
2.
Sergi Sastre Francisco Maculé Sandra Lasurt Josep-María Segur Lluis Lozano Montse Nuñez Santiago Suso 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(4):393-397
Five patients with idiopathic transient osteoporosis were examined. Bone scanning and MRI was helpful in the diagnosis to differentiate of necrosis and all patients recovered completely with conservative and symptomatic treatment. There was no history of trauma in all patients. MRI was realized previously in all cases to confirm the diagnosis and after the resolution of symptomathology. 相似文献
3.
Successful Liver and Kidney Transplantation From Cadaveric Donors With Left-Sided Bacterial Endocarditis 总被引:1,自引:0,他引:1
Francisco Caballero Antonio Lopez-Navidad Milagrosa Perea Catiana Cabrer Lluis Guirado Ricard Solà 《American journal of transplantation》2005,5(4):781-787
Bacterial infections are frequent in cadaveric organ donors and can be transmitted to the transplantation recipient, which could have devastating consequences for the recipients if adequate preventive measures are not adopted.
From the 355 consecutive brain dead cadaveric organ donors procured at our center in the last four years, 2000–2003, four of them (1.1%) had bacterial endocarditis as cause of death. The bacteria responsible for the endocarditis were Staphylococcus epidermidis, coagulase-negative Staphylococcus , Staphylococcus hominis and Streptococcus viridans , respectively. We performed five kidney and two liver transplantations on seven recipients. All donors and recipients received antibiotic treatment against the germ causing the respective endocarditis.
Infection by the bacteria responsible for the endocarditis in the respective donors was not transmitted to any of the recipients. Six of the seven recipients were alive with normal-functioning grafts after between 13 and 24 months' follow-up. Transplantectomy was performed on one kidney recipient due to thrombosis of the renal vein of the graft not related to the endocarditis.
Liver and kidney transplantation from donors dying from bacterial endocarditis can be performed without causing the transmission of infection to the recipient or the dysfunction of the graft. 相似文献
From the 355 consecutive brain dead cadaveric organ donors procured at our center in the last four years, 2000–2003, four of them (1.1%) had bacterial endocarditis as cause of death. The bacteria responsible for the endocarditis were Staphylococcus epidermidis, coagulase-negative Staphylococcus , Staphylococcus hominis and Streptococcus viridans , respectively. We performed five kidney and two liver transplantations on seven recipients. All donors and recipients received antibiotic treatment against the germ causing the respective endocarditis.
Infection by the bacteria responsible for the endocarditis in the respective donors was not transmitted to any of the recipients. Six of the seven recipients were alive with normal-functioning grafts after between 13 and 24 months' follow-up. Transplantectomy was performed on one kidney recipient due to thrombosis of the renal vein of the graft not related to the endocarditis.
Liver and kidney transplantation from donors dying from bacterial endocarditis can be performed without causing the transmission of infection to the recipient or the dysfunction of the graft. 相似文献
4.
Adrià Arboix Lluis García-Eroles Emili Comes Montserrat Oliveres Miquel Balcells Gustavo Pacheco Cecilia Targa 《European journal of neurology》2003,10(4):429-435
We assessed predictors of spontaneous early neurological recovery after acute ischemic stroke by means of multivariate analysis in a cohort of 1,473 consecutive patients treated at one academic center. At hospital discharge, spontaneous neurological improvement or good outcome was defined as grades 0-2 of the Rankin scale, and poor outcome (no improvement or in-hospital death) as grades 3-5. Spontaneous recovery of neurological deficit at the time of discharge from the hospital was observed in 16% of patients with cerebral infarction (n = 238). Dysarthria-clumsy hand syndrome improved in 44% of patients and was the only variable significantly associated with in-hospital functional recovery in three logistic regression models that in addition to lacunar syndromes, included demographic variables, cardiovascular risk factors, and clinical variables [odds ratio (OR) 2.56], neuroimaging findings (OR 2.48), and outcome data (OR 2.39), respectively. Clinical factors related to severity of infarction available at stroke onset have a predominant influence upon in-hospital outcome and may help clinicians to assess prognosis more accurately. Our work gives a contribution into prognostic factors after acute ischemic stroke. With regard to patterns of stroke, dysarthria-clumsy hand syndrome was a significant predictor of spontaneous in-hospital recovery in ischemic stroke patients. 相似文献
5.
Ana Velasco Victor Palomar-Asenjo Laura Ga?an Lluis Catasus Nuria Llecha Angel Panizo Victor Palomar-Garcia Miquel Quer Xavier Matias-Guiu 《Diagnostic molecular pathology》2005,14(2):109-114
The familial paraganglioma syndrome is an autosomal dominant disorder characterized by the presence of carotid body paragangliomas and, less frequently, paragangliomas of the glomus jugulare, glomus vagale, and adrenal pheochromocytomas. Germline mutations of the genes for succinate dehydrogenase subunits D, B, or C (SDHD, SDHB, SDHC) have been identified in some kindreds with familial paraganglioma. In this study, we report the clinicopathologic features of four different kindreds with familial paraganglioma, which were screened for germline mutations in the SDHD gene. DNA was obtained from tumor and normal tissue, as well as from peripheral blood. Mutation analysis was performed by single-strand conformation polymorphism analysis and DNA sequencing. SDHD germline mutations were detected in the affected family members of the four families, as well as in several asymptomatic carriers. An identical mutation in exon 4 of SDHD (334-337delACTG) was identified in two apparently unrelated kindreds. The third family showed a germline mutation in exon 2 (W43X). The mutations present in these three families had been previously described in Spanish families, suggesting a founder effect. The fourth family exhibited a mutation in exon 2 of SDHD (170-171delTT), which had not been previously identified. The affected family members of the four kindreds showed paragangliomas, located in the head and neck region, and all of them were benign. These results confirm that genetic testing of SDHD may be a powerful tool for the identification of the syndrome in patients with multiple or bilateral paragangliomas. 相似文献
6.
Debril MB Renaud JP Fajas L Auwerx J 《Journal of molecular medicine (Berlin, Germany)》2001,79(1):30-47
Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors, initially described as molecular targets for synthetic compounds that induce peroxisome proliferation. PPARgamma is the best characterized of the PPARs. The heterodimer of PPARgamma with the retinoid X receptor (RXR) plays a crucial role in adipogenesis and insulin sensitization. The RXR/PPARgamma heterodimer furthermore has been reported to have important immunomodulatory activities and to affect cell proliferation/differentiation pathways in various malignancies. PPARgamma is activated by a number of naturally occurring fatty acid derivatives and by several synthetic compounds, including the thiazolidinediones and L-tyrosine-based insulin sensitizers. This review gives an overview of the pleiotropic functions of PPARgamma and discusses the wide-ranging medical implications that modulation of PPARgamma activity might have for various diseases, ranging from obesity and type 2 diabetes to cancer and inflammation. 相似文献
7.
Zei G Lisa A Fiorani O Magri C Quintana-Murci L Semino O Santachiara-Benerecetti AS 《European journal of human genetics : EJHG》2003,11(10):802-807
A total of 202 Sardinian male subjects were examined for 13 biallelic stable markers, the complex 49a,f/TaqI system and three microsatellites of the Y chromosome in order to investigate, through surname analysis, on a possible territorial heterogeneity inside the island. The study of geographical distribution and linguistic derivation of Sardinian surnames allow us to discover their 'probable place of origin' and reconstruct ancient genetic isolates which borders are, today, no more recognizable. The molecular analysis revealed that about 90% of the Sardinian Y chromosomes fell into haplogroups E-M35, G-M201, I-M26, J-12f2 and R-M269. In contrast with the territorial homogeneity of these haplogroups, when the individuals were distributed according to their birthplace, a significant difference between the three historically and culturally distinct geographical areas into which Sardinia can be subdivided was observed when the individuals were distributed according to the ancestral location of surnames. In particular, the major contribution to this heterogeneity is due to the 'Sardinian-specific' haplogroup I-M26 (almost completely associated with the 49a,f-Ht12/12f2-10Kb/YCAIIa-21/YCAIIb-11 compound haplotype), which shows both a significantly higher incidence in the central-eastern (archaic) area and a significantly lower frequency in the northern area. The results of this study agree with the hypothesis that the ancestral homeland of this specific subset of haplogroup I is the mountainous central-eastern area of Sardinia, where the population underwent a long history of isolation since ancient times, and highlight the informative power of the surname analysis. 相似文献
8.
Jaume Alijotas-Reig Manel Casellas-Caro Raquel Ferrer-Oliveras Elisa Llurba-Olive Eduard Hermosilla Miquel Vilardell-Tarres Lluis Cabero-Roura 《American journal of reproductive immunology (New York, N.Y. : 1989)》2008,60(3):229-237
Problem Anti-beta2 -Glicoprotein-1 antibodies (anti-β2 GPI-ab) have been related to recurrent miscarriage (RM) with conflicting results. The aim was to evaluate the role of anti-β2 -GPI-ab as unique biological marker in RM related to antiphospholipid (aPL).
Method of study A cohort study that included 59 cases, divided in two groups, was designed: group 1 comprised 43 pregnant women with 'obstetric' antiphospholipid syndrome (APS) and group 2 included 16 cases with similar complaints but only having repeatedly anti-β2 -GPI-ab. Previous thrombosis and/or inherited thrombophilia were excluded. Lupus anticoagulant, anticardiolipin antibodies (aCA), anti-β2 -GPI-ab, and other autoantibodies were analyzed. Miscarriages, premature births, pre-eclampsia, live births, placental and systemic thromboses were studied.
Results No differences in previous obstetric complications were detected ( P = 1.00–0.164). After the treatment, differences in number of obstetric complications were not seen ( P = 1.00). Live births were similar in two groups (88.4% and 93.7%; P = 1.00). Placental thrombosis was equal in both groups, 93.3% versus 80% ( P = 1.00).
Conclusion These results suggest that anti-β2 -GPI-ab may be considered a biological marker for obstetric APS. 相似文献
Method of study A cohort study that included 59 cases, divided in two groups, was designed: group 1 comprised 43 pregnant women with 'obstetric' antiphospholipid syndrome (APS) and group 2 included 16 cases with similar complaints but only having repeatedly anti-β
Results No differences in previous obstetric complications were detected ( P = 1.00–0.164). After the treatment, differences in number of obstetric complications were not seen ( P = 1.00). Live births were similar in two groups (88.4% and 93.7%; P = 1.00). Placental thrombosis was equal in both groups, 93.3% versus 80% ( P = 1.00).
Conclusion These results suggest that anti-β
9.
Dr Miguel A. Asenjo Lluisa Baré José M. Bayas Andreu Prat Rafel Lledó Joan Grau Lluis Salleras 《European journal of epidemiology》1994,10(5):625-632
The results of the prospective application of Horn's Severity of Illness Index in a teaching hospital during 1987, 1989, and 1990 constitute the basis of the present report. The average overall severity of illness scores for the three years were 1.42 in 1987, 1.65 in 1989, and 1.46 in 1990. Most of the processes evaluated in the three periods showed an overall distribution among severity levels 1 and 2, both overall and when the seven dimensions of the severity of illness index were analyzed. A statistically significant correlation between the overall severity of illness and average length of stay was found for patients in 1989 and 1990. The length of stay differed significantly in the different severity levels. When the four levels of the seven dimensions of the severity of illness index for 1987, 1989, and 1990 were compared, it was observed that figures were not uniformly distributed. There was a statistically significant association between severity of illness for hospital service and pharmacy charges per hospital stay for both 1989 and 1990, as well as a statistically significant inverse relationship between severity of illness and the number of claims per hospital service in both periods of time. Case-mix methods that account for the severity of patients constitute a useful indicator of quality for the management of different hospital services and of the hospital as a whole. 相似文献
10.
G. Cecchi F. Colomo C. Poggesi C. Tesi 《Pflügers Archiv : European journal of physiology》1993,423(1-2):113-120
An apparatus for studying the mechanics of isolated frog heart myocytes is described. The cells are held horizontal in a through of Ringer solution by means of two suction micropipettes. Myocyte force is measured with an opto-electronic system recording the deflection of the tip of one micropipette, which acts as a cantilever force probe. The force probes are selected for compliance according to the force a myocyte is expected to develop in a given condition, so as to limit myocyte shortening during force development to no more than 1% of the slack cellular length (l
0). The other micropipette, which is stiff relative to the forces measured, is mounted on an electromagnetic-loudspeaker motor by which controlled-velocity length changes, of preset size and in either direction, are imposed on myocytes. The force transducer has a sensitivity of 5–10 mV/nN, with a frequency response of 700–900 Hz in Ringer solution and a resolution of 0.5–1 nN. The motor with a suction micropipette can complete controlled-velocity length ramps within 1.5–2.0 ms, across a range of ±100 m at a resolution of 8.0 nm. These values correspond, for frog-heart myocytes 200 m and 400 m long, to 25%–50% l
0 and 0.002%–0.004% l
0 respectively. 相似文献