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61.
Frenoy N Gildelgado M Pham P Salvucci M Chahine A Chabli A Misset J Debuire B 《Oncology reports》1996,3(2):385-390
Although lymphoid malignancies have been widely studied at the molecular level, no group has reported on the simultaneous investigation of t(14;18) chromosomal translocation, B-cell clonality and bcl2 gene expression. We have performed PCR analysis of t(14;18) translocation and B-cell clonality as well as semi-quantitation of bcl2 expression by Western blotting on a group of 41 patients treated at our institution for lymphoid malignancies. The t(14;18) translocation was observed in 10 out of 40 cases (25%) with a prevalence in the subgroup of centrofollicular lymphoma (9 out of 19, or 47%, which includes one patient in complete clinical remission). bcl2 was overexpressed in 84% of the patients (21/25) and B monoclonality was observed in 21 out of 37 B-cell neoplasia patients (57%) with or without a t(14;18) translocation. In 4 patients, bcl2 overexpression, which has been implicated in the sensitivity to a variety of cytotoxic drugs, was the only abnormality detected. Studies are currently underway to determine whether semi-quantitation of bcl2 expression provides improved prediction of a patient's response to chemotherapy. 相似文献
62.
Renal abnormalities in sickle cell disease. Sickle cell nephropathy is indicated by sickled erythrocytes, with the consequent effects of decreased medullary blood flow, ischemia, microinfarct and papillary necrosis. Impaired urinary concentrating ability, renal acidification, hematuria, and potassium secretion are also found. There may be a causal relationship between an increase in nitric oxide synthesis and experimental sickle cell nephropathy, and some studies have indicated that the progression of sickle cell nephropathy is hemodynamically mediated. Although there are many studies showing that proteinuria, nephrotic syndrome, chronic progressive renal failure, and acute renal failure syndromes are the outcome of this disease, the pathogenic mechanism(s) and potential therapies remain to be elucidated. Survival of patients with sickle cell nephropathy who progress to end-stage renal disease (ESRD) is equal to non-diabetic ESRD patients, and graft survival rates are also similar for those who undergo renal transplantation. This article presents a historical review of the glomerular and tubular disorders associated with sickle cell nephropathy, and reviews therapeutic indications to slow its progression. Further research is needed. 相似文献
63.
Aberrant crypt focus promotion and glucose intolerance: correlation in the rat across diets differing in fat, n-3 fatty acids and energy 总被引:1,自引:0,他引:1
Koohestani N; Chia MC; Pham NA; Tran TT; Minkin S; Wolever TM; Bruce WR 《Carcinogenesis》1998,19(9):1679-1684
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994)
and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the
striking similarity in lifestyle risk factors for colorectal cancer and
insulin resistance, proposed that the hyperinsulinemia, glycemia and
hypertriglyceridemia associated with insulin resistance promotes colon
cancer. To compare the effect of diet on colon cancer promotion and insulin
resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids
and energy in pairwise comparisons on average size of aberrant crypt foci
(ACF) and on glucose intolerance in the same animals in a single
experiment. Diets high in fat and energy increased and diets with increased
n-3 fatty acids and calorie restriction decreased both ACF growth and
glucose intolerance compared with control diets. The measures of promotion
of colon cancer and insulin resistance were strongly correlated (n = 98, r
= 0.67, P < 0.001). In addition, both were highly correlated with daily
energy intake (r = 0.62 and 0.66) and were also correlated with basal
(post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P <
0.01). We concluded that ACF growth and glucose intolerance are correlated
for a wide range of diets and that increased circulating energy (glucose
and triglycerides) may lead to both colon cancer promotion and insulin
resistance.
相似文献
64.
von Euler M Pham TM Hillefors M Bjelke B Henriksson B von Euler G 《Experimental neurology》2000,163(1):1-8
The organic solvent toluene is widely used in industry. The threshold limit value for extended occupational exposure to toluene is presently set to 200 ppm in the United States. We have investigated the effect of an inhalation exposure of 80 ppm for 4 weeks (6 h/day, 5 days/week), followed by a postexposure period of at least 4 weeks, on behavior and brain features in the rat. Toluene exposure appeared to affect spatial memory, since toluene-exposed rats showed a longer time in the correct quadrant in a Morris swim maze. This effect may indicate that the exposed rats used their praxis strategy longer before they started to look for the platform elsewhere. Toluene-exposed rats showed trends for increases in both locomotion and rearing behaviors and a significantly reduced beam-walk performance. The area of the cerebral cortex, especially the parietal cortex, was decreased by 6-10% in toluene-exposed rats, as shown by magnetic resonance imaging of living rats and autoradiograms of frozen brain sections. The K(D) and B(max) values of the dopamine D(3) agonist [(3)H]PD 128907 were not affected by toluene, as measured in caudate-putamen and subcortical limbic area using biochemical receptor binding assays and in caudate-putamen and islands of Calleja using quantitative receptor autoradiography. Hence, previously demonstrated persistent effects by toluene on the binding characteristics of radioligands binding to both D(2) and D(3) receptors seem to indicate a persistent effect of toluene selectively on dopamine D(2) receptors. Taken together, the present results indicate that exposure to low concentrations of toluene leads to persistent effects on cognitive, neurological, and brain-structural properties in the rat. 相似文献
65.
Urinary hyaluronic acid and hyaluronidase: markers for bladder cancer detection and evaluation of grade 总被引:20,自引:0,他引:20
Lokeshwar VB Obek C Pham HT Wei D Young MJ Duncan RC Soloway MS Block NL 《The Journal of urology》2000,163(1):348-356
PURPOSE: Specific patterns of progression and frequent recurrence of bladder tumors determine the choice of treatment, frequency of surveillance, quality of life, and ultimately, patient prognosis. The prognosis would be improved if an accurate noninvasive test was available for diagnosis. Identification of markers that function in bladder cancer progression would be helpful in designing such diagnostic tests. The glycosaminoglycan, hyaluronic acid (HA), promotes tumor metastasis. Hyaluronidase (HAase), an endoglycosidase, degrades HA into small fragments that promote angiogenesis. We have previously shown that both HA and HAase are associated with bladder cancer and may function in bladder tumor angiogenesis. In this study we examined whether urinary HA and HAase levels serve as bladder cancer markers. MATERIALS AND METHODS: Among the 513 urine specimens analyzed, 261 were from transitional cell carcinoma (TCC) patients, 9 from patients with non-TCC tumors, and 243 from controls (normals, patients with other genitourinary (GU) conditions or a history of bladder cancer (HxBCa)). The urinary HA and HAase levels were measured by two ELISA-like assays that utilize a biotinylated HA binding protein for detection. These levels were normalized to total urinary protein and were expressed as ng./mg. (HA test) and mU/mg. (HAase test), respectively. RESULTS: The urinary HA levels were elevated (2.5 to 6.5 fold) in bladder cancer patients (1173.7+/-173.4; n = 261) as compared with normals (246.1+/-38.5; n = 41); GU patients (306.6+/-32.2; n = 133), and patients with a HxBCa (351.1+/-49.1; n = 69) (p <0.001). The urinary HAase levels were elevated (3 to 7 fold) in G2/G3 bladder cancer patients (26.2+/-3.2) as compared with normals (4.5+/-0.9) and patients with either GU conditions (5.8+/-1.3), HxBCa (8.2+/-2.6) or G1 tumors (9.7+/-2.5) (p <0.001). The HA test showed 83.1% sensitivity, 90.1% specificity and 86.5% accuracy in detecting bladder cancer, regardless of the tumor grade. The HAase test showed 81.5% sensitivity, 83.8% specificity and 82.9% accuracy to detect G2/G3 patients. Combining the inferences of the HA and HAase tests (HA-HAase test) resulted in detection of bladder cancer, regardless of tumor grade and stage, with higher sensitivity (91.2%) and accuracy (88.3%), and comparable specificity (84.4%). CONCLUSION: Our results show that the HA-HAase urine test is a noninvasive, highly sensitive and specific method for detecting bladder cancer and evaluating its grade. 相似文献
66.
67.
Christopher Sie Ravi Kant Christian Peter Andreas Muschaweckh Monika Pfaller Lucy Nirschl Helena Domínguez Moreno Tereza Chadimov Gildas Lepennetier Tanja Kuhlmann Rupert
llinger Thomas Engleitner Roland Rad Thomas Korn 《The Journal of experimental medicine》2022,219(8)
In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis. 相似文献
68.
Cerebrovascular responses to somatomotor stimulation in Parkinson’s disease: A multivariate analysis
Sam C Barnes Ronney B Panerai Lucy Beishon Martha Hanby Thompson G Robinson Victoria J Haunton 《Journal of cerebral blood flow and metabolism》2022,42(8):1547
Parkinson’s disease (PD) is a common neurodegenerative disorder, yet little is known about cerebral haemodynamics in this patient population. Previous studies assessing dynamic cerebral autoregulation (dCA), neurovascular coupling (NVC) and vasomotor reactivity (VMR) have yielded conflicting findings. By using multi-variate modelling, we aimed to determine whether cerebral blood flow (CBF) regulation is impaired in PD patients.55 healthy controls (HC) and 49 PD patients were recruited. PD subjects underwent a second recording following a period of abstinence from their anti-Parkinsonian medication. Continuous bilateral transcranial Doppler in the middle cerebral arteries, beat-to-beat mean arterial blood pressure (MAP; Finapres), heart rate (HR; electrocardiogram), and end-tidal CO2 (EtCO2; capnography) were measured. After a 5-min baseline period, a passive motor paradigm comprising 60 s of elbow flexion was performed. Multi-variate modelling quantified the contributions of MAP, ETCO2 and neural stimulation to changes in CBF velocity (CBFV). dCA, VMR and NVC were quantified to assess the integrity of CBF regulation.Neural stimulation was the dominant input. dCA, NVC and VMR were all found to be impaired in the PD population relative to HC (p < 0.01, p = 0.04, p < 0.01, respectively). Our data suggest PD may be associated with depressed CBF regulation. This warrants further assessment using different neural stimuli. 相似文献
69.
70.
OBJECTIVE: To evaluate the need for initial inpatient treatment for patients being treated with low-dose intramuscular methotrexate for low-risk gestational trophoblastic neoplasia (GTN). STUDY DESIGN: Clinical notes of all patients treated with low-dose intramuscular methotrexate for low-risk GTN were analyzed and side effects noted. RESULTS: There were no episodes of increased uterine bleeding requiring extra medical intervention. There were 7 cases of chest pain; none required a change from methotrexate chemotherapy. CONCLUSION: Patients being treated with low-dose intramuscular methotrexate for low-risk GTN do not need to be treated routinely in the hospital for their first treatment cycle. 相似文献