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1.
Morphologic and histochemical characteristics of skeletal muscle after long-term intramuscular electrical stimulation. 总被引:1,自引:0,他引:1
The purpose of this investigation was to examine the morphologic and histochemical characteristics of paraspinal muscles in patients with scoliosis after long-term electrical stimulation. Thirty-six children with idiopathic scoliosis, who had been treated with implantable muscle stimulators, had paraspinal muscle biopsies at the time of implantable muscle stimulator removal. Group A patients whose curve did not progress, had 2.9 years of stimulation stopped at skeletal maturity, with a further 1.5 years of nonstimulation before implant removal and biopsy. In group B patients, who had an average of 2.3 years of stimulation, the curve progressed and stimulation was continued until fusion and biopsy. Neither group showed any increase in the frequency of pathologic changes of paraspinal muscles contrasted with values reported in the literature for scoliotic muscle. In group A patients there was an increased proportion of type 1 fibers on the convex side of the curve compared to the concavity. Despite this finding the curves did not require fusion, suggesting that the increased percentage of type 1 fibers was not the cause of the scoliosis. In group B patients there was an even higher type 1 concentration on the convex side contrasted to the convex side of group A patients. 相似文献
2.
M Kurian L Spinelli J Delavelle J P Willi M Velazquez V Chaves W Habre K Meagher-Villemure E Roulet J G Villeneuve M Seeck 《Epileptic Disord》2007,9(1):20-31
Multiple structural and functional imaging modalities are available to localize the epileptogenic focus. In pre-surgical evaluation of children with pharmacoresistant epilepsy, investigations with the maximum yield should be considered in order to reduce the complexity of the workup. OBJECTIVE: To determine the extent to which PET, ictal/interictal SPECT and its co-registration with the patient's MRI contributes to correct localization of the epileptogenic focus, surgical intervention and to the post surgical outcome in paediatric patients. METHODS: The study population included children and adolescents with pharmacoresistant epilepsy (n = 50) who underwent preoperative evaluation, surgery and had postoperative follow-up for at least 12 months. Outcome was measured by postoperative seizure frequency using Engel's classification. RESULTS: Thirty-nine patients (78%) became completely seizure free after surgical intervention. The likelihood to benefit from surgical treatment was significantly higher if localization with more imaging modalities (MRI, PET, SPECT) were concordant with respect to the resected brain area (p < 0.01). Preoperative PET examination provided better localizing information in patients with extratemporal epilepsy and/or dysplastic lesions, whereas SPECT was found to be superior to PET in patients with temporal lobe epilepsy and/or tumors (p < 0.05). No significant difference was noted in the surgical outcome in younger or older age group, in children with or without special education needs. CONCLUSION: In paediatric epilepsy pre-surgical evaluation, the combined use of multiple functional imaging modalities for a precise localisation of the epileptogenic focus is worthwhile for both extratemporal and temporal lobe epilepsy, also when EEG and MRI alone are non-contributive, given the potential benefit of complete postoperative seizure control. 相似文献
3.
Jamieson M Bourque Eric J Velazquez Robert H Tuttle Linda K Shaw Christopher M O'Connor Salvador Borges-Neto 《Journal of nuclear cardiology》2007,14(2):165-173
BACKGROUND: Left ventricular ejection fraction (LVEF) is a significant predictor of morbidity and death. The nuclear summed rest score (SRS) measures myocardial perfusion defects and provides prognostic information, but its effects on long-term outcomes are not fully established. Moreover, information regarding the potential interaction between these 2 covariates is limited. The purpose of this study was to determine whether the mortality risk associated with LVEF is the same across all values of SRS in a population undergoing evaluation for ischemic heart disease. METHODS AND RESULTS: We examined 3,187 patients who underwent cardiac catheterization and perfusion single photon emission computed tomography imaging with a maximum follow-up of 8.1 years and median follow-up of 3.1 years. Cox proportional hazards modeling showed that increasing nuclear SRS and decreasing LVEF were independently associated with a higher long-term mortality rate, with a clinically significant interaction between them (P = .032). Patients with a normal LVEF and a high SRS (greater perfusion abnormality) have a prognosis similar to those with a reduced LVEF. CONCLUSIONS: Resting perfusion studies provide prognostic information for long-term survival and significantly impact the interpretation of mortality risk associated with changes in LVEF. Patient prognostication, risk stratification, and future research using these variables should take this interaction into account. 相似文献
4.
Jamieson M. Bourque Eric J. Velazquez Robert H. Tuttle Linda K. Shaw Christopher M. O’Connor Salvador Borges-Neto 《Journal of nuclear cardiology》2007,14(2):165-173
Background Left ventricular ejection fraction (LVEF) is a significant predictor of morbidity and death. The nuclear summed rest score
(SRS) measures myocardial perfusion defects and provides prognostic information, but its effects on long-term outcomes are
not fully established. Moreover, information regarding the potential interaction between these 2 covariates is limited. The
purpose of this study was to determine whether the mortality risk associated with LVEF is the same across all values of SRS
in a population undergoing evaluation for ischemic heart disease.
Methods and Results We examined 3,187 patients who underwent cardiac catheterization and perfusion single photon emission computed tomography
imaging with a maximum follow-up of 8.1 years and median follow-up of 3.1 years. Cox proportional hazards modeling showed
that increasing nuclear SRS and decreasing LVEF were independently associated with a higher long-term mortality rate, with
a clinically significant interaction between them (P=.032). Patients with a normal LVEF and a high SRS (greater perfusion abnormality) have a prognosis similar to those with
a reduced LVEF.
Conclusions Resting perfusion studies provide prognostic information for long-term survival and significantly impact the interpretition
of mortality risk associated with changes in LVEF. Patient prognostication, risk stratification, and future research using
these variables should take this interaction into account.
Supported by a grant from the Tom & Lynn Royster Foundation. Durham, NC, and a National Institutes of Health Research Fellowship
Grant (T5 GM08679-04), Bethesda, Md. 相似文献
5.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
6.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
7.
Detecting pre-ovulatory luteinizing hormone surges in urine 总被引:2,自引:1,他引:2
Kesner JS; Knecht EA; Krieg EF Jr; Wilcox AJ; O'Connor JF 《Human reproduction (Oxford, England)》1998,13(1):15-21
The study objectives were to determine (i) if pre-ovulatory luteinizing
hormone (LH) surges, undetected in urine by two immunoradiometric assays
(IRMA), were detectable by an ultrasensitive immunofluorometric assay
(IFMA) and (ii) the influence of creatinine adjustment on the detection and
timing of the urinary LH surges. Daily urine specimens were contributed by
healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for
an epidemiological study conducted in 1983-1985. Specimens were selected as
having been previously assayed by two IRMA without consistently detecting
LH surges. These urine specimens were remeasured using an IFMA and adjusted
for creatinine concentration. IFMA measurements revealed unambiguous LH
surges in all cycles. Adjusting IRMA urinary LH values for creatinine
concentrations revealed previously undetected LH surges in four of eight
cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH
surges by 1-5 days. These results demonstrate an IFMA that detects pre-
ovulatory LH surges in unpreserved, frozen urine from cycles where such
surges were previously undetectable. Further, creatinine adjustment can
markedly affect detection and timing of the onset and peak of the urinary
LH surge. While our analysis suggests that this adjustment improves the
validity of the LH measure, this requires further investigation.
相似文献
8.
The whitespotted-I (WSP1) mutant of Drosophila melanogasteris characterized by the presence of an 8.7 kb retrotransposon(B104) inserted in the regulatory region of the white locus.The frequency of reversion in both somatic tissue and the germlineafter exposure to three different alkylating agents has beenanalysed. To determine if germinal revertants were induced byprecise excision of the insertional element we analysed severalphenotypic revertants using PCR and Southern blot tecniques.The results indicate that, under our experimental conditions,the mutagens used did not induce excision of B104 in the whitegene. In addition, the revertant phenotypes obtained were dueto the existence of second site modifiers acting on expressionof white. Such modifiers map near the white locus and, at leastin one case, may correspond to suppressorofwhitespotted.
1To whom correspondence should be addressed. Tel: +34 3 5812731; Fax: +34 3 5812387; Email: xamena{at}cc.uab.es 相似文献
9.
María Jesús Fernández Aceñero MD PhD Cristina Díaz del Arco CDdA MD Carme Dinarés CD MD PhD Tania Labiano TL MD Eva Tejerina ET MD PhD Mª José Bernabé MJ B MD Elena Forcen EF MD Melchor Saiz-Pardo MSP MD Pablo Pérez PP MD Maria D. Lozano MDL MD PhD 《Diagnostic cytopathology》2023,51(1):26-35
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples. 相似文献
10.
Velazquez JR Lacy P Mahmudi-Azer S Moqbel R 《International archives of allergy and immunology》1999,118(2-4):447-449
Eosinophils synthesize and release a number of cytokines and chemokines, including RANTES, a potent chemoattractant particularly for memory T cells and eosinophils. Long-term (>12 h) incubation with interferon-gamma (IFN-gamma) has been shown to activate eosinophils and induce expression of membrane receptors. We hypothesized that IFN-gamma mobilizes intracellular RANTES in eosinophils in advance of mediator release. Highly purified peripheral blood eosinophils were obtained from asthmatics and stimulated with IFN-gamma at 500 U/ml for time course analysis up to 2h. By specific ELISA, RANTES was detected in supernatants (80+/-15 pg per 2x10(6) cells) following 120min of stimulation. Immunoreactive RANTES in resting cells (5x10(7) eosinophils) was detected in two intracellular compartments in studies of subcellular fractionation by density gradient centrifugation. After 10 min IFN-gamma stimulation, RANTES immunoreactivity was confined to crystalloid granules. RANTES was redistributed from secretory granules to light-membrane fractions after 60 min of IFN-gamma incubation. Our data suggest that rapid mobilization and release of RANTES occurs from stimulated eosinophils. These findings may have important implications for the role of IFN-gamma in activating human eosinophils, particularly in severe chronic asthma or viral exacerbation of asthmatic inflammation, where this cytokine may play a role. 相似文献