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11.
Proliferative activity in craniopharyngiomas: clinicopathological correlations in adults and children 总被引:2,自引:0,他引:2
Raghavan R Dickey WT Margraf LR White CL Coimbra C Hynan LS Rushing EJ 《Surgical neurology》2000,54(3):241-7; discussion 248
BACKGROUND: Craniopharyngiomas are slow-growing, locally invasive intracranial tumors that can generate considerable morbidity, and recurrences are often difficult to manage. Because reliable morphologic criteria for accurately predicting the clinical outcome of these tumors are lacking, we evaluated the growth potential of craniopharyngiomas by measuring their proliferative activity based on MIB-1 immunostaining for the Ki-67 antigen, which is expressed during all phases of the cell cycle except G(0.) METHODS: Paraffin sections from 37 cases of craniopharyngiomas were immunostained with the monoclonal antibody MIB-1, and a labeling index was derived in each case from an the with the highest labeling. RESULTS: MIB-1 immunoreactivity was mainly confined to the peripheral palisaded epithelium of craniopharyngiomas. In adult craniopharyngiomas, MIB-1 labeling indices (MIB-LI) varied from 0.1% to 34.6% (mean 8.9%; SD 9. 8), and in pediatric tumors the indices ranged from 1.8% to 15.0% (mean 6.3%; SD 3.7). MIB-LI was not found to be an independent predictor of recurrence, although in all the pediatric cases that recurred, MIB-LI in the second specimen was greater. CONCLUSIONS: The actively proliferating compartment in craniopharyngiomas seems to be the peripheral palisaded epithelium. Low MIB-LI observed in the majority of tumors is in concordance with the slow growth and low-grade invasiveness associated with craniopharyngiomas. However, unlike other intracranial neoplasms, where Ki-67 labeling indices have been useful in predicting tumor behavior, a clear relationship could not be demonstrated between MIB-1 immunoreactivity, morphological features and clinical outcomes in adults or children with craniopharyngiomas. 相似文献
12.
Early events leading to renal injury in obese Zucker (fatty) rats with type II diabetes 总被引:16,自引:0,他引:16
Coimbra TM Janssen U Gröne HJ Ostendorf T Kunter U Schmidt H Brabant G Floege J 《Kidney international》2000,57(1):167-182
Early events leading to renal injury in obese Zucker (fatty) rats with type II diabetes. BACKGROUND: More than half of the new patients admitted to dialysis therapy in some centers are diagnosed with type IIb diabetes, that is, diabetes associated with obesity. This study searched for a common final pathway of renal damage in this progressive renal disease. METHODS: The evolution of biochemical and morphological renal changes was examined in 6- to 60-week-old Zucker rats (fa/fa-rats), a model of obesity associated with type II diabetes. RESULTS: fa/fa-rats exhibited pronounced hyperinsulinemia and hyperlipidemia at 6 weeks and became diabetic after 14 weeks of age. Significant focal segmental glomerulosclerosis was first noted in 18-week-old fa/fa-rats and tubulointerstitial damage and proteinuria in 40-week-old fa/fa-rats. A comparison of kidneys of six-week-old fa/fa-and lean control (Fa/?) rats by immunohistology revealed a 1.8-fold increase in glomerular monocyte/macrophage counts in fa/fa-rats and a significant increase in de novo desmin expression in podocytes. Electron microscopy demonstrated an increase in the number of podocyte mitochondria and intracytoplasmic protein and fat droplets. Podocyte desmin scores markedly increased until week 18 in fa/fa-rats, whereas glomerular monocyte/macrophage counts peaked at 3.2-fold at week 14. Podocyte desmin expression, but not glomerular macrophage infiltration, correlated with damage in adjacent tubular cells, as evidenced by their de novo expression of vimentin. Progressive glomerular hypertrophy was detected in fa/fa-rats after 10 weeks. GBM width was significantly increased in 14-week-old fa/fa-rats as compared with lean controls. Mesangial cell activation (de novo expression of alpha-smooth muscle actin) and proliferation was low to absent throughout the observation period in fa/fa-rats. Renal cell death counts (TUNEL) remained unchanged in 6- to 40-week-old fa/fa-rats. Tubulointerstitial myofibroblast formation and matrix accumulation occurred late during the study duration in fa/fa-rats. CONCLUSION: These data suggest that early progressive podocyte damage and macrophage infiltration is associated with hyperlipidemia and type IIb diabetes mellitus, and antedates both the development of glomerulosclerosis and tubulointerstitial damage. 相似文献
13.
In this study we investigated the effect of heparin on renal injury and renal transforming growth factor-beta (TGF-beta) production in adriamycin (AD)-injected rats. Thirty-nine female Wistar rats were injected with AD (3.5 mg/kg body weight, i.v.) and 27 with 0.15 M NaCl solution (group C). Fifteen days later we started to inject heparin, 500 U/day, s.c., in 20 of the AD-injected animals (AD-H group). Three months after beginning treatment, urine samples were collected to quantify albumin, creatinine and TGF-beta. The rats were killed and the kidneys removed for histological, immunohistochemical, ELISA and RNA studies. All AD-injected animals showed structural renal changes (p < 0.05). However, the glomerular alterations were less intense in rats from group AD-H (p < 0.05). The percentage of glomerulosclerosis was 0.11 +/- 0.08 in group C, 14.7 +/- 12.8 in group AD (treated only with AD) and 3.42 +/- 2.3 in group AD-H. Renal cortex immunostaining for TGF-beta and mRNA content of this polypeptide was higher in both groups of animals injected with AD compared to controls (p < 0.05). These animals also presented a higher rate of urinary TGF-beta excretion (p < 0.05), which was 202 +/- 11 in group C, 1,103 +/- 580 in group AD and 1,564 +/- 328 pg/mg Ucreat in group AD-H. However, TGF-beta activity in the glomerular-conditioned media from the rats of group AD was higher than in the glomerular-conditioned media from the rats of group AD-H. In conclusion, treatment with heparin reduces glomerular damage in rats with AD-induced nephropathy but does not modify tubulointerstitial lesions or the renal production of TGF-beta. 相似文献
14.
OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age. 相似文献
15.
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
16.
The role of associated injuries on outcome of blunt trauma patients sustaining pelvic fractures 总被引:7,自引:0,他引:7
Gustavo Parreira J Coimbra R Rasslan S Oliveira A Fregoneze M Mercadante M 《Injury》2000,31(9):677-682
In order to identify the prognostic factors and to evaluate the impact of associated injuries in the outcome of patients with pelvic fractures, a retrospective review of the medical records of patients admitted with a pelvic fracture during a 42-month period was carried out. Demographic data, the mechanism of injury, the physiologic status on admission, associated injuries, pelvic fracture classification, complications and mortality were analysed. One hundred and three patients were included in the study. Fifty-nine were male, and the mean age was 34. The mean Revised Trauma Score (RTS) and Injury Severity Score (ISS) were 7.1 and 20, respectively. Pedestrian vs vehicle (59%), was the most frequent mechanism of injury. Twenty patients died (19%) most frequently due to "shock". Complications developed in 37 patients (36%), pneumonia being the most frequent. Age greater than 40 years (p=0.02), "shock" upon admission (p=0.002), a Glasgow Coma Scale (GCS)<9, Head AIS>2 (p<0. 001), Chest AIS>2 (p=0.007), and abdominal AIS>2 (p=0.03) all correlated with increased mortality. No correlation between pelvic fracture classification or fracture stability with mortality was observed. The outcome of patients with pelvic fractures due to blunt trauma correlates with the severity of associated injuries and physiological derangement on admission rather than with characteristics of or the type of fracture. 相似文献
17.
Cludia Farinha Patrícia Barreto Rita Coimbra Adela Iutis Maria Luz Cachulo Jos Cunha-Vaz Yara T. E. Lechanteur Carel B. Hoyng Rufino Silva 《Investigative ophthalmology & visual science》2022,63(9)
PurposeTo determine the association between rare genetic variants in complement factor H (CFH) and phenotypic features in age-related macular degeneration (AMD) patients from the Coimbra Eye Study (CES).MethodsAMD patients from the Incidence CES () underwent ophthalmologic examination and color fundus photography, spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence, and near-infrared imaging. Multimodal phenotypic characterization was carried out in a centralized reading center. The coding and splice-site regions of the CFH gene were sequenced through single-molecule molecular inversion probe–based next-generation sequencing in association with the EYE-RISK consortium. Variants with minor allele frequency <0.05 resulting in splice-site or protein change were selected. Differences in phenotypic features between carriers and noncarriers were analyzed using generalized estimated equations logistic regression models, considering intereye correlations.ResultsWe included 39 eyes of 23 patients carrying rare CFH variants and 284 eyes of 188 noncarriers. Carrier status was associated with having higher drusen burden in the macula in the inner Early Treatment Diabetic Retinopathy Study circle (odds ratio [OR], 5.44 [95% confidence interval {CI}, 1.61–18.37]; P = 0.006), outer circle (OR, 4.37 [95% CI, 1.07–17.77]; P = 0.04), and full grid (OR, 4.82 [95% CI, 1.13–20.52]; P = 0.033). In SD-OCT, a lower total macular volume and lower inner retinal layers’ volume (OR, 0.449 [95% CI, 0.226–0.894]; P = 0.023; OR, 0.496 [95% CI, 0.252–0.979]; P = 0.043) and pigment epithelial detachments (PEDs) (OR, 5.24 [95% CI, 1.08–25.44]; P = 0.04) were associated with carrying a rare CFH variant. Carriers with subretinal drusenoid deposits (SDD) had the rare variant P258L in all cases except one.ConclusionsWe identified in our cohort phenotypic differences between carriers and noncarriers of rare variants in the CFH gene. Carriers had more severe disease, namely superior drusen burden, PEDs, and thinner retinas. The rare variant P258L may be associated with SDD. Carriers are probably at increased risk of progression. NCT02748824相似文献
18.
The regulation of hemopoiesis in long-term bone marrow cultures. II. Stimulation and inhibition of stem cell proliferation 总被引:6,自引:1,他引:6
The isolation of a DNA synthesis inhibitor (NBME fraction IV) and stimulator (RBME fraction III) specific for the hemopoietic stem cell (CFU-s) from freshly isolated normal adult and regenerating murine bone marrow, respectively, has been well documented. We have utilized long- term liquid bone marrow cultures in a further analysis of the role of these factors in the regulation of CFU-s proliferation. Our results show that shortly after feeding, at a time when the cultured CFU-s are actively proliferating, high levels of the hemopoietic stem cell proliferation stimulator fraction III can be isolated from the culture medium. In contrast, the presence of essentially noncycling CFU-s found in cultures fed 8-10 days previously correlates with high levels of the hemopoietic stem cell inhibitor fraction IV. These results suggest that a certain balance between these factors determines CFU-s proliferation in the long-term cultures. In support of this, DNA synthesis in actively cycling CFU-s in the long-term cultures is inhibited for at least 3 days by the addition of excess NBME fraction IV (inhibitor). Furthermore, DNA synthesis in noncycling cultured CFU-s is stimulated for at least 5 days by the addition of RBME fraction III (stimulator). 相似文献
19.
Jelinek J; Fairbairn LJ; Dexter TM; Rafferty JA; Stocking C; Ostertag W; Margison GP 《Blood》1996,87(5):1957-1961
A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas. 相似文献
20.
C. Beglinger MD C. Knezevic MD L. Jeker U. Grötzinger MD PD Dr. K. Gyr MD MPH & TM 《Digestive diseases and sciences》1983,28(4):350-352
In five conscious dogs with chronic gastric fistulas we studied the effect of somatostatin solutions on pentagastrin-stimulated acid secretion. Somatostatin was dissolved in 0.154 M NaCl alone or in the same amount of saline to which dog albumin had been added to give a 0.5% solution. Somatostatin produced a dose-dependent inhibition of pentagastrin-stimulated gastric secretion. However, the inhibition was significantly less when somatostatin was dissolved in saline as compared to saline plus albumin. This study suggests that albumin should be added to somatostatin solutions to preserve biological activity, and it confirms previous reports indicating that, without albumin, basic peptides have a tendency to stick to infusion systems. 相似文献