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51.
Soto-Hernández JL Morales VA Lara Giron JC Balderrama Bañares J 《Clinical imaging》1999,23(4):209-214
Actinomycosis is an uncommon cause of intracranial infection. Epidural empyema represents about 6% of CNS actinomycotic lesions. A case of an epidural empyema with parietal bone osteomyelitis caused by Actinomyces israelii is presented. Relevant neuroimaging features were bone erosions and a multiloculated collection with annular contrast enhancing on CT. Postoperative MRI revealed extensive involvement of the neighbor dura, falx, and subdural space. MRI was crucial to follow-up the response to antibiotic treatment. 相似文献
52.
BACKGROUND: An ipsilateral neck dissection is mandatory during initial treatment stages II-IV oral carcinomas. However, no consensus exists whether or not to perform an elective contralateral neck dissection. METHODS: Five hundred thirteen consecutive cases of squamous cell carcinoma (269 tongue, 135 floor of the mouth, 44 inferior gingiva, 65 retromolar trigone) were reviewed. Tumor stages were: 69 T1, 227 T2, 217 T3-T4, 263 N0, 250 N1-N3. A total of 563 neck dissections were performed in 448 patients. Univariate and multivariate analysis of risk factors were performed using logistic regression. RESULTS: Two hundred twenty-three patients (49.8%) had positive nodes in the specimen (182 ipsilateral, 36 bilateral, 5 contralateral). Contralateral neck recurrences occurred in 38 cases (33 not submitted to a contralateral neck dissection initially). Multivariate logistic regression analysis demonstrated that clinical stage (p = .0001), tumor crossing midline (p = .0011), and floor of the mouth involvement (p = .0236) were the most important predictors of contralateral metastasis. CONCLUSION: The contralateral side of the neck is a common and potentially preventable site of recurrence in tumors of the oral cavity. The multivariate model obtained discriminates patients with low and high risk (more than 20%) of contralateral metastasis. The application of this mathematical model can be useful for the indication of contralateral neck dissections, because not all tumors crossing midline are associated to a high risk (stages I and II tumors not involving the floor of the mouth) and not all tumors not crossing midline are at low risk (stages III and IV tumors involving the floor of the mouth). 相似文献
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54.
J. Arpa Gutiérrez C. Morales M. Lara C. Muñoz M. García-Rojo A. Caminero M. Gutiérrez 《Acta neuropathologica》1993,86(5):542-545
A Portuguese female, aged 47 years, who had emigrated to Spain, was admitted to the hospital in 1991 for pontine haematoma. The patient, four siblings and her father were affected by a peripheral neuropathy, indicating autosomal dominant inheritance. The patient presented in the 2nd decade with sensory and motor neuropathy beginning in the lower extremities. Alternating constipation and diarrhoea, and urinary incontinence became uncontrollable. She had to be colostomised, and, eventually, confined to a wheelchair from the age of 43. Neurological examination showed bilateral facial involvement, and severe signs of sensory and motor peripheral neuropathy, and later right hemiplegia. There were abnormalities of atrial rhythm and left bundle branch block. Computerised axial tomography and magnetic resonance images demonstrated left-sided pontine haemorrhage. Nerve conduction studies revealed severe diminution of motor conduction velocity and absence or reduction of amplitude of sensory and motor action potentials. Inanition and a respiratory infection led to her death. Clinical diagnosis was type I familial amyloid polyneuropathy (FAP). Postmortem examination demonstrated amyloid deposits in peripheral nerves, including spinal roots and cranial nerves, leptomeninges, thyroid, breasts, heart, adrenal glands, kidneys, intestines, pancreas, and meningeal and some pontine vascular structures. Advanced pontine haematoma was verified. Cerebral haemorrhage usually occurs with cerebrovascular amyloidosis, but exceptionally with FAP. A minority of patients presenting with CNS haemorrhage showed arteriovenous malformation or embolism [Da Silva Horta and Dias Coelho (1960) Arch de Vecchi Anal Patol Med Clin 31=163–172]. However, amyloid deposition in some small pontine vessels could have played a role in the pathogenesis of haemorrhage in the present case. 相似文献
55.
Glenn Liu David R Gandara Primo N Lara Derek Raghavan James H Doroshow Przemyslaw Twardowski Philip Kantoff William Oh KyungMann Kim George Wilding 《Clinical cancer research》2004,10(3):924-928
PURPOSE: Flavopiridol is a cyclin-dependent kinase inhibitor with preclinical activity against prostate cancer cell lines. A Phase II trial was conducted to determine the activity of flavopiridol in patients with metastatic hormone-refractory prostate cancer. EXPERIMENTAL DESIGN: A total of 36 patients was enrolled from several institutions and treated with a 72-h continuous infusion of flavopiridol every 14 days at the eventual starting dose of 40 mg/m(2)/day. Dose escalation up to 60 mg/m(2)/day was permitted if no significant toxicity was observed. Responses were assessed every 12 weeks. Only those patients completing four courses of the 72-h infusion were considered evaluable for response because the primary objective was to determine progression-free survival at 6 months given the cytostatic nature of the agent. RESULTS: This study was conducted in a two-stage fashion. During the first stage, at least 20 evaluable patients needed to be enrolled to assess response. There were 22 of 36 patients evaluable for response. No objective responses were observed. Only 4 patients had stable disease for 16, 26, 29, and 48 weeks, respectively, stopping the trial by design as only 3 of 22 (14%) of the patients met the 6-month progression-free survival end point. The most common toxicities were diarrhea (grade 1 and 2) and nausea, although some grade 3 and 4 diarrhea (11 and 6%, respectively) were evident. CONCLUSIONS: Flavopiridol has disappointing single-agent activity in hormone-refractory prostate cancer when administered at this dose and schedule. Its use in prostate cancer should be reserved for evaluation in combination therapies or alternative schedules. 相似文献
56.
Primo N Lara Paul Frankel Philip C Mack Paul H Gumerlock Irina Galvin Cynthia L Martel Jeff Longmate James H Doroshow Heinz Josef Lenz Derick H M Lau David R Gandara 《Clinical cancer research》2003,9(12):4356-4362
PURPOSE: Tumor hypoxia confers chemotherapy resistance. Tirapazamine is a cytotoxin that selectively targets hypoxic cells and has supra-additive toxicity with platinums and taxanes in preclinical studies. We conducted a Phase I study of tirapazamine, carboplatin, and paclitaxel and assessed potential plasma markers of hypoxia as surrogates for response. EXPERIMENTAL DESIGN: Forty-two patients with advanced solid tumors were treated at four dose levels; parallel dose escalations were carried out in chemotherapy-naive and previously treated subjects. Pre and post-therapy plasma levels of the hypoxia-induced proteins plasminogen activator inhibitor-1 and vascular endothelial growth factor were measured. RESULTS: Three of four chemotherapy-na?ve patients developed dose-limiting toxicities at dose level 4 (grade 3 stomatitis/infection, grade 3 emesis, and grade 4 febrile neutropenia). Four of seven previously treated patients developed dose-limiting toxicities at dose level 3, including one death [grade 3 myalgia, grade 3 infection/grade 4 neutropenia, grade 3 infection/grade 4 neutropenia, and grade 5 infection (death)/grade 4 neutropenia]. Of 38 patients assessable for response, 3 had a complete response, 1 a partial response, 1 an unconfirmed partial response, and 23 had stable disease in at least one evaluation; 10 quickly progressed. One complete responder had normalization of vascular endothelial growth factor and plasminogen activator inhibitor-1 levels. CONCLUSION: Dose levels 3 (carboplatin AUC of 6, 225 mg/m(2) paclitaxel, and 330 mg/m(2) tirapazamine) and 2 (carboplatin AUC 6, 225 mg/m(2) paclitaxel, and 260 mg/m(2) tirapazamine) are the maximum tolerated doses for chemotherapy naive and patients treated previously, respectively. Dose level 3 is the experimental arm of a Phase III Southwest Oncology Group trial (S0003) in advanced non-small cell lung cancer. Potential markers of tumor hypoxia may be useful correlates in studies of hypoxic cytotoxins and are being prospectively investigated in S0003. 相似文献
57.
58.
P C Lara A Rey C Santana J L Afonso J M Diaz G J González R Apolinario 《Radiotherapy and oncology》1998,49(2):163-167
PURPOSE: To assess whether tumour proliferation as measured by Ki67 immunostaining has any predictive value for local control in bladder cancer patients treated by radiotherapy. PATIENTS AND METHODS: Fifty-five patients suffering from infiltrating bladder carcinoma recommended for radical radiotherapy (66 Gy/6-7 weeks) were included in this study. Paraffin-embedded pre-treatment tumour sections were stained with the Ki67 antibody. The percentage of Ki67-positive nuclei was correlated with established prognostic factors, local control and survival. RESULTS: The Ki67 index was not related to local control in our patients when the median was selected as the cut-off value. Patients with tumours with a very low (<27%) Ki67 index had better local control at 5 years (69%) than patients with tumours with greater (>27%) Ki67 expression indices (31.5%) (P<0.05; log-rank test). CONCLUSIONS: Ki67 immunostaining was a feasible method to estimate tumour proliferation. Patients with very low proliferating tumours seemed to achieve better local control after fractionated radiotherapy compared to other patients. Further studies are needed with a greater number of patients to accurately define the role of Ki67 expression in predicting tumour repopulation during fractionated radiotherapy. 相似文献
59.
Schmidt AP Lara DR de Faria Maraschin J da Silveira Perla A Onofre Souza D 《Brain research》2000,864(1):40-43
In the mammalian CNS, glutamate and GABA are the principal neurotransmitters mediating excitatory and inhibitory synaptic events, respectively, and have been implicated in the neurobiology of seizures. Guanine-based purines, including the nucleoside guanosine and the nucleotide GMP, have been shown to antagonize glutamatergic activity at the receptor level and the other purine nucleoside adenosine is a well-known modulator of seizure threshold. In the present study we investigated the anticonvulsant effect of i. p. guanosine and GMP against seizures induced by the glutamate agonist quinolinic acid (QA) or the GABA(A) antagonist picrotoxin in mice. Animals were pretreated with an i.p. injection of saline, guanosine or GMP 30 min before either an i.c.v. injection of 4 microliter QA (36.8 nmol) or a subcutaneous injection of picrotoxin (3.2 mg/kg). All animals pretreated with vehicle followed by QA or picrotoxin presented seizures, which were completely prevented by the NMDA antagonist MK-801 and the GABA agonist phenobarbital, respectively. Guanosine and GMP dose-dependently protected against QA-induced seizures, up to 70 and 80% at 7.5 mg/kg, with ED(50)=2. 6+/-0.4 and 1.7+/-0.6 mg/kg, respectively. Conversely, neither guanosine, GMP nor MK-801 affected picrotoxin-induced seizures, indicating some degree of specificity towards the glutamatergic system. This study suggests anticonvulsant properties of i.p. guanosine and GMP, which may be related with antagonism of glutamate receptors. 相似文献
60.
R Lara S Cerutti J A Salonia R A Olsina L D Martinez 《Food and chemical toxicology》2005,43(2):293-297
The objective of this work was to develop a method to determine the metal content in wine samples from the province of Mendoza in Argentina. Ten samples of white wine and 10 samples of red wine available in the supermarket were analyzed for the metals aluminium, cadmium, calcium, chromium, copper, iron, nickel, lead and zinc by electrothermal atomic spectrometry (ETAAS) and ultrasonic nebulization was coupled to inductively coupled plasma optical emission spectrometry (USN-ICP-OES). The aluminium, cadmium, calcium, copper, iron, lead, zinc, chromium concentrations were between 17.0-18.0 microg l(-1), 1.0-4.7microg l(-1), 10.0-15.0 mg l(-1), 23.0-28.0 microg l(-1), 480-790 microg l(-1), 50-90 microg l(-1), 24-130 microg l(-1), and <0.2-6.25 microg l(-1), respectively. The levels compare well with those reported for similar wines from some other parts of the world. A significant aspect in this paper is the samples mineralization step, which allowed the direct determination of the metals. Concerning to the Cd determination, a refluxing digestion system was used for the pretreatment of the samples. 相似文献