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91.
Nerve growth factor (NGF) is a well-characterized neurotrophic factor that plays a crucial role during development in the growth, differentiation, and maintenance of brain neurons as well as in the reparative response of the adult brain to neuronal damage. Recent studies have shown that acute axonal loss occurs in multiple sclerosis (MS) and its animal model, experimental allergic encephalomyelitis (EAE), and that NGF suppresses clinical symptoms of EAE in nonhuman primates. Aim of the present study was to investigate the role of NGF in the regenerative response of the adult brain to neuronal damage occurring in EAE. Using EAE rats, we have found that exogenous NGF injection and NGF deprivation (NGF autoimmunization) can act on growth and differentiation of brain precursor cells in the subventricular zone (SVZ) of EAE rats. Moreover, NGF administration in brain of EAE rats stimulates the expression of early neuronal markers on proliferating precursor cells of the SVZ. The data obtained demonstrated that NGF and its antibody affect bromodeoxyuridine (BrdU) incorporation and NGF receptor expression by SVZ progenitor cells in the brain of EAE rats.  相似文献   
92.
BACKGROUND/AIMS: Docosahexaenoic acid (C22:6, DHA) is an omega-3 fatty acid required for the normal development of the mammalian nervous and visual system. DHA is provided by the mother during pregnancy and lactating period. Mother's DHA supplementation during pregnancy, and even before pregnancy, has been suggested. DHA can be provided by marine oils, egg's yolk phospholipids, single cell algae oils, the pure fatty acid, or by the ethyl ester derivative (DHA-EE). Another way to provide DHA can be by sn-2 docosahexaenyl monoacylglyceride (DHA-MG), obtained by the treatment of fish oil with stereospecific lipases. sn-2 Fatty acid monoacylglycerides can be more easily absorbed at the intestine than other fatty acid derivatives. METHODS: Female rats fed with a synthetic, which provided essentially no DHA, received a 40-day supplementation of either DHA-EE or DHA-MG. Plasma and erythrocyte fatty acid composition were assessed by gas chromatography at day 0 and 40 of supplementation. RESULTS: DHA-EE increased plasma and erythrocyte DHA by 15 and 11.9%, respectively, with no modification of arachidonic acid (AA) content. DHA-MG supplementation increased plasma and erythrocyte DHA by 24 and 23.8%, respectively, but reduced AA by 5.5 and 3%, respectively. CONCLUSIONS: We conclude that in the rat, DHA-MG supplementation allows a higher plasma and erythrocyte DHA content than DHA-EE with minor modification of AA content.  相似文献   
93.
PURPOSE: To retrospectively correlate high-risk proliferative breast lesions (radial scar, atypical lobular hyperplasia, lobular carcinoma in situ and papillary lesions) diagnosed on core biopsy with the definitive histopathological diagnosis obtained after surgical excision or with the follow-up, in order to assess the role of core biopsy in such lesions. To discuss the management of the patient after a core biopsy diagnosis of high-risk proliferative breast lesion. MATERIAL AND METHODS: We evaluated 74 out of 1776 core biopsies consecutively performed on 67 patients. The histopathologic findings were as follows: 11 radial scars (RS), 3 atypical lobular hyperplasias (ALH), 3 lobular carcinomas in situ (LCIS), 57 benign papillary lesions. All patients underwent bilateral mammography, whole-breast ultrasound with a linear-array broadband transducer, and core biopsy with a 14 Gauge needle and a mean number of samples of 5 (range 4-7). Sixty-two of 67 patients, for a total of 69/74 lesions, underwent surgical biopsy despite benign histopathologic findings, mostly because of highly suspicious imaging for malignancy (BIRADS 4-5), whereas 5 patients refused surgery and have been followed up for a least 18 months and are still being followed up (2 with RS, 1 with ADH and 2 with papillary lesions). RESULTS: Among the core biopsied lesions with a diagnosis of RS (n = 11) pathology revealed one ductal carcinoma in situ (DCIS) (this case was characterized by granular microcalcifications on mammography and by a mass with irregular margins on ultrasound). Also in the group of ADH (n = 3) pathology revealed one DCIS (lesion not visible on mammography but depicted as a suspicious mass on US). In the group of LCIS (n = 3) pathologists found an invasive lobular carcinoma (ILC). Among the benign papillary lesions (n = 57) histopathologic analysis of the surgical specimen revealed 7 malignant lesions (4 papillary carcinomas and 3 DCIS), whose mammographic and ultrasound findings were indistinguishable from benign lesions. Altogether there were 10 false negative results (underestimation) out of 74 core biopsies with a diagnosis of high-risk proliferative breast lesions. CONCLUSION: The high rate of histological underestimation after core biopsy (10/74) (13.5%) demands a very careful management of patents with a core biopsy diagnosis of high-risk proliferative breast lesions, especially in the case of RS, lobular neoplasia and papillary lesions. However, the high imaging suspicion for malignancy prompts surgery. It is possible to assume that, when there is a low imaging suspicion for malignancy, when enough tissue has been sampled for pathology and no atypia is found within the lesions, surgery is not mandatory but a very careful follow-up is recommended. We must underline that there is no agreement regarding the quantity of tissue to sample. Vacuum-assisted biopsy may lead to better results, although there is as yet no proof that it can actually replace surgery in this group of lesions, since it seems only to reduce but not abolish the histological underestimation.  相似文献   
94.
Santos M  Kunkar V  García-Iturralde P  Tendillo FJ 《Anesthesia and analgesia》2004,98(2):359-63, table of contents
A synergistic effect of nonselective cyclooxygenase (COX) inhibitors on morphine-induced decrease of isoflurane minimum alveolar concentration (MAC(ISO)) has been observed in the rat. We studied the influence of specific COX-2 inhibitors on this decrease of MAC. Sixty-four female rats were anesthetized with isoflurane in oxygen. The animals were grouped into saline solution, aspirin (30 mg/kg), morphine (1 mg/kg), morphine (1 mg/kg) + aspirin (30 mg/kg), meloxicam (1 and 3 mg/kg), and morphine (1 mg/kg) + meloxicam (1 and 3 mg/kg). Then the MAC(ISO) was determined from alveolar gas samples at the time of tail clamp. The groups treated with saline solution, aspirin, and 1 and 3 mg/kg meloxicam did not express any statistically relevant changes among them. The administration of morphine + meloxicam 1 or 3 mg/kg significantly reduced the MAC(ISO) just as in the group where only morphine was administered (morphine 1.35% +/- 0.07%, morphine + 1 mg/kg meloxicam 1.36% +/- 0.04%, and morphine + 3 mg/kg meloxicam 1.37% +/- 0.08%). The greatest reduction of MAC(ISO) was after administration of morphine + aspirin (1.19% +/- 0.05%). The administration of meloxicam does not potentiate the morphine-induced decrease of MAC(ISO) in the rat. IMPLICATIONS: A synergistic effect between morphine and aspirin on isoflurane minimum alveolar concentration has been observed in the rat--an effect that does not occur between morphine and meloxicam.  相似文献   
95.
The accuracy of mammography, sonography and magnetic resonance imaging (MRI) in identifying residual disease after neoadjuvant chemotherapy is evaluated and imaging findings are correlated with pathologic findings. Fifteen patients enrolled in an experimental protocol of preoperative neoadjuvant chemotherapy underwent clinical examination, mammography, sonography and dynamic MRI, performed in this order, before and respectively after 2 and 4 cycles of neoadjuvant chemotherapy. Four radiologists, two for mammography, one for sonography and one for MR, examined the images, blinded to the results of the other examinations. All patients underwent radical or conservative surgery, and imaging findings were compared with pathologic findings. MRI identified 2/15 (13.3.%) clinically complete response (CR), 9/15 (60%) partial response (PR), 3/15 (20%) stable disease (SD) and 1/15 (6.7%) progressive disease. Mammography identified 1/15 (6.7%) clinically CR, 8/15 (53.3%) PR and 4/15 (27%) SD, and was not able to evaluate the disease in 2/15 (13%) cases. Sonography presented the same results as MRI. Therefore, MRI and sonography compared to mammography correctly identified residual disease in 100 vs. 86%. MRI resulted in two false-negative results because of the presence of microfoci of in situ ductal carcinoma (DCIS) and invasive lobular carcinoma (LCI). MRI was superior to mammography in cases of multifocal or multicentric disease (83 vs. 33%). Sonography performed after MRI improves the accuracy in evaluation of uncertain foci of multifocal disease seen on MR images with an increase of diagnostic accuracy from 73 to 84.5%. MRI assesses response to neoadjuvant chemotherapy better than traditional methods of physical examination and mammography.  相似文献   
96.
BACKGROUND: Postoperative nausea and vomiting (PONV) is one of the most significant problems in laparoscopic surgery. The antiemetic effects of metoclopramide and droperidol used alone or in combination for prevention of PONV after laparoscopic cholecystectomy (LC) were assessed in this prospective, double blind, placebo controlled randomized study. PATIENTS AND METHODS: A series of 140 patients, ASA physical status I or II, were included in the study. Patients were randomized to one of the following groups: 1, placebo; 2, metoclopramide 10 mg after the induction of anesthesia and placebo at 12 h postoperatively; 3, droperidol 1.25 mg after the induction of anesthesia and droperidol 1.25 mg at 12 h postoperatively; and 4, droperidol 1.25 mg plus metoclopramide 10 mg after the induction of anesthesia and droperidol 1.25 mg at 12 h postoperatively. Patients were observed for 24 hours for PONV, pain, need for rescue analgesics, and adverse events. RESULTS: Data were analyzed using the Student's t-test and chi-square test, with P < 0.05 considered statistically significant. The mean incidence of PONV was 54% with placebo, 42% with metoclopramide, 14% with two doses of droperidol alone, and 11% with a combination of metoclopramide plus droperidol. The patients receiving a combination of metoclopramide and droperidol had a significantly lower rate of PONV than those administered metoclopramide alone (P < 0.05) or placebo (P < 0.001). Those receiving two-dose droperidol alone also had a significantly lower incidence of PONV compared with metoclopramide (P < 0.05) and placebo (P < 0.001). There was no statistically significant difference between the metoclopramide and placebo groups. Sedation was significantly greater in patients administered droperidol 12 h postoperatively. CONCLUSION: The combination of metoclopramide and droperidol, and two-dose droperidol alone, were found to significantly decrease the incidence of PONV after LC, whereas metoclopramide alone proved inefficient.  相似文献   
97.
We evaluated the effect of acetaminophen (APAP), given as a single, 1g/kg body weight dose, on expression and activity of rat liver multidrug resistance-associated protein 2 (Mrp2) and P-glycoprotein (P-gp), two major canalicular drug transporters. The studies were performed 24h after administration of the drug. APAP induced an increase in plasma membrane content of Mrp2 detected by western blotting, consistent with increased detection of the protein at the canalicular level by immunoflourescence microscopy. In vivo biliary excretion of dinitrophenyl-S-glutathione, a well known Mrp2 substrate, was slightly but significantly increased by APAP, agreeing well with upregulation of the transporter. Basal biliary excretion of oxidized glutathione, an endogenous Mrp2 substrate, was also increased by APAP, likely indicating increased hepatic synthesis as a result of APAP-induced oxidative stress followed by accelerated canalicular secretion mediated by Mrp2. APAP also increased the expression of P-gp detected by western blotting and immunofluorescence microscopy as well as the in vivo biliary secretory rate of digoxin, a model P-gp substrate. Because specific APAP-conjugated metabolites are Mrp2 substrates, we postulate that induction of Mrp2 by APAP may represent an adaptive mechanism to accelerate liver disposition of the drug. In addition, increased Mrp2-mediated elimination of oxidized glutathione may be essential in maintaining the redox equilibrium in the hepatocyte under conditions of APAP-induced oxidative stress.  相似文献   
98.
BACKGROUND: Splenic marginal zone lymphoma (SMZL) is a well defined pathologic entity. However, questions regarding the bone marrow infiltration rate, the minimal diagnostic data set, and therapy remain unanswered. METHODS: Clinical-pathologic features and outcomes of 57 consecutive patients who had splenomegaly with no clinically significant lymphadenomegaly and who were diagnosed with SMZL with or without (+/-) villous lymphocytes (VL) were reviewed. RESULTS: SMVL +/- VL occurred mostly in elderly males (median age, 62 years +/- 10 years; male-to-female ratio, (1.85). Anemia was recorded in 49% of patients, and 30% of patients had moderate thrombocytopenia. Leukocytosis and leukopenia were found in 33% and 14% of patients, respectively, and typical VL were found in 84% of patients. Serology for hepatitis C virus infection was positive in 16% of patients, and a small monoclonal component was detected in 36% of patients. The bone marrow was infiltrated with an intrasinusoidal component in all patients. Thirteen patients were monitored using a watch-and-see policy, and they remained alive 1-5 years after diagnosis. Overall, 21 patients (36%) underwent splenectomy; and, in all patients, the diagnosis of SMZL was confirmed histologically in the surgical specimens. Twenty-five patients received single-agent therapy, which included either alkylators or pentostatine, and they achieved an overall response rate (ORR) of 65% and 87%, respectively: Polychemotherapy was administered to 6 patients (ORR, 83%). The median survival for all patients in the series was not reached, and it is expected that 70% of patients will be alive at 5 years. CONCLUSIONS: Up to 20% of patients who had SMZL +/- VL could be monitored using a watch-and-wait policy. The bone marrow intrasinusoidal infiltration pattern may be a valuable diagnostic hallmark, thus obviating diagnostic splenectomy. The issues regarding prognostic stratification and the best therapeutic strategy need to be addressed in properly designed, prospective trials.  相似文献   
99.
Protein Kinase (casein kinase 2, CK2) is a serine-threonine kinase that is frequently dysregulated in many human tumors. Therefore we hypothesized that peptides capable of binding to the CK2 acidic domain may exhibit potential anticancer properties. By screening a random cyclic peptide phage display library, we have identified a novel peptide, P15, that abrogated CK2 phosphorylation by blocking the substrate in vitro. To verify its potential antineoplastic effect, P15 was fused to the cell-penetrating peptide derived from the HIV-Tat protein. Interestingly, P15-Tat induced apoptosis as evidenced by rapid caspase activation and cellular cytotoxicity in a variety of tumor cell lines. Furthermore, direct injection of P15-Tat into C57BL6 mice bearing day 7-established solid tumors, resulted in substantial regression of the tumor mass. Our findings describe a new proapoptotic cyclic peptide that blocks the CK2 phosphorylation and exhibits antitumor effect in vivo, indicating that the P15 peptide may potentially be used clinically to treat solid tumors or as an adjuvant for cancer therapy.  相似文献   
100.
The aim of this study was to assess the utility of 99mTc-sestamibi scintimammography (SM) in patients with suspected primary or recurrent breast cancer. Forty-four (44) breast lesions (17 with suspected recurrence of disease) in 40 patients were included into the study. In these patients, the results of conventional diagnostic methods were equivocal or inconclusive. Twenty-one (21) lesions were palpable and 23 lesions were not. Histological examinations performed during the follow-up revealed malignancy in 24 specimens. SM correctly identified 21 of them, as well as 12 true negatives. There were 8 false-positive studies; therefore, the sensitivity of SM was 87.5%, specificity was 60%, positive predictive value (PPV) was 72.4%, and the negative predictive value (NPV) was 80%. The sensitivity in palpable lesions was 100%; three (3) false negatives, 1 recurrence, and 2 cancers, all of them nonpalpable. In conclusion, SM is useful in equivocal palpable lesions for resolving diagnostic uncertainty after conventional examination, and can limit the number of surgical interventions for benign disease. However, its use in nonpalpable tumors is not recommended.  相似文献   
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