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141.
PURPOSE: Temozolomide, a DNA methylating agent used to treat melanoma, induces DNA damage, which is repaired by O6-alkylguanine alkyltransferase (ATase) and poly(ADP-ribose) polymerase-1 (PARP-1)-dependent base excision repair. The current study was done to define the effect of temozolomide on DNA integrity and relevant repair enzymes as a prelude to a phase I trial of the combination of temozolomide with a PARP inhibitor. EXPERIMENTAL DESIGN: Temozolomide (200 mg/m2 oral administration) was given to 12 patients with metastatic malignant melanoma. Peripheral blood lymphocytes (PBL) were analyzed for PARP activity, DNA single-strand breakage, ATase levels, and DNA methylation. PARP activity was also measured in tumor biopsies from 9 of 12 patients and in PBLs from healthy volunteers. RESULTS: Temozolomide pharmacokinetics were consistent with previous reports. Temozolomide therapy caused a substantial and sustained elevation of N7-methylguanine levels, a modest and sustained reduction in ATase activity, and a modest and transient increase in DNA strand breaks and PARP activity in PBLs. PARP-1 activity in tumor homogenates was variable (828 +/- 599 pmol PAR monomer/mg protein) and was not consistently affected by temozolomide treatment. CONCLUSIONS: The effect of temozolomide reported here are consistent with those documented in previous studies with temozolomide and similar drug, dacarbazine, demonstrating that a representative patient population was investigated. Furthermore, PARP activity was not inhibited by temozolomide treatment and this newly validated pharmacodynamic assay is therefore suitable for use in a proof-of-principle phase I trial a PARP-1 inhibitor in combination with temozolomide.  相似文献   
142.
PURPOSE: Renal cancer response to interleukin 2 (IL-2) therapy and patient survival has been correlated with tumor histology and carbonic anhydrase IX (CAIX) expression. In an effort to confirm and expand these observations, we examined CAIX expression in pathology specimens from renal cancer patients who had previously received IL-2 therapy. EXPERIMENTAL DESIGN: Paraffin-embedded tissue sections of renal cancer were immunostained with the MN-75 monoclonal antibody to CAIX and expression levels were correlated with histologic findings and clinical outcome. RESULTS: Tissue specimens were obtained from 66 patients; 27 of whom (41%) had responded to IL-2-based therapy. Fifty-eight specimens were assessed as clear cell, with 56, 33, and 4 having alveolar, granular, and papillary features, respectively. Twenty-four (36%), 31 (47%), and 11 (17%) were classified into good, intermediate, and poor prognosis groups according to the Upton pathology model. Forty-one specimens (62%) had high CAIX expression. Twenty-one of 27 (78%) responding patients had high CAIX expressing tumors compared with 20 of 39 (51%) nonresponders (odds ratio, 3.3; P = 0.04). Median survival was prolonged (P = 0.04) and survival >5 years was only seen in high CAIX expressers. In patients with intermediate pathologic prognosis, all nine responders had high CAIX expression versus 11 of 22 nonresponders. A resultant group with good pathologic prognosis alone or with intermediate pathologic prognosis and high CAIX contained 26 of 27 (96%) responders compared with 18 of 39 (46%) nonresponders (odds ratio, 30; P < 0.01) and exhibited longer median survival (P < 0.01). CONCLUSIONS: CAIX expression seems to be an important predictor of outcome in renal cell carcinoma patients receiving IL-2-based therapy and may enhance prognostic information obtained from pathology specimens.  相似文献   
143.
Recent postmortem studies in humans suggest that defects in GABAergic neurotransmission might contribute to the neuropathology associated with schizophrenia. Disturbances in GABAergic systems may also contribute to the sensorimotor gating deficits classically observed in schizophrenic patients, including deficits in prepulse inhibition (PPI). To explore the relationship, the current study examined the integrity of PPI and startle habituation in knockout (KO) mice that lack the GABA synthesizing enzyme glutamic acid decarboxylase 65 (GAD 65). GAD65 KO mice displayed normal baseline and habituated startle responses, which did not differ from GAD65 wild-type (WT) or heterozygous (HET) mice. However, GAD65 KO mice showed robust deficits in PPI which were reversed by the atypical antipsychotic agent clozapine. These results lend support to the view that abnormalities in GABAergic systems might contribute to the basic pathophysiological mechanisms in schizophrenia.  相似文献   
144.
In order to characterize the efficacy of dry powder inhalers, in vitro measurements are much easier to perform than human deposition studies, especially in early stages of drug development. In this study, lung deposition and delivered dose of radiolabeled Foradil P inhaled with the Aerolizer were measured in 10 healthy subjects. These data were then compared with data derived from an in vitro assessment of the device output and particle size distribution combined with mathematical modeling of lung deposition (modified ICRP-model). Delivered dose and lung deposition increased slightly but statistically significant with the inhalation peak flow in both the in vivo data and the in vitro data. The delivered dose ranged from 60% to 80% and lung deposition, relative to the fill weight, from 13% to 28%. Differences between the in vitro and in vivo data were slight and statistically not significant. This study indicates that in vitro assessment of device performance, in combination with lung deposition delivery data, are in good agreement with deposition data measured in healthy subjects. Since there was only a slight flow rate dependency of lung deposition without clinical relevance, it may additionally be concluded that the Aerolizer is a robust, easy to handle inhalation device with stable and reproducible drug delivery characteristics.  相似文献   
145.
146.
Proteases comprise a variety of enzymes defined by their ability to catalytically hydrolyze the peptide bonds of other proteins, resulting in protein lysis. Cathepsins, specifically, encompass a class of at least twenty proteases with potent endopeptidase activity. They are located subcellularly in lysosomes, organelles responsible for the cell's degradative and autophagic processes, and are vital for normal lysosomal function. Although cathepsins are involved in a multitude of cell signaling activities, this chapter will focus on the role of cathepsins(with a special emphasis on Cathepsin B) in neuronal plasticity. We will broadly define what is known about regulation of cathepsins in the central nervous system and compare this with their dysregulation after injury or disease. Importantly, we will delineate what is currently known about the role of cathepsins in axon regeneration and plasticity after spinal cord injury. It is well established that normal cathepsin activity is integral to the function of lysosomes. Without normal lysosomal function, autophagy and other homeostatic cellular processes become dysregulated resulting in axon dystrophy. Furthermore, controlled activation of cathepsins at specialized neuronal structures such as axonal growth cones and dendritic spines have been positively implicated in their plasticity. This chapter will end with a perspective on the consequences of cathepsin dysregulation versus controlled, localized regulation to clarify how cathepsins can contribute to both neuronal plasticity and neurodegeneration.  相似文献   
147.
Purpose:To describe the clinical profile of patients presenting with uveitis following COVID-19 infection at a tertiary care eye hospital in South India.Methods:In this retrospective chart review, all consecutive cases presenting with an acute episode of intraocular inflammation and a history of COVID-19 infection diagnosed within the preceding 6 weeks, between March 2020 and September 2021, were included. Data retrieved and analyzed included age, sex, laterality of uveitis, and site of inflammation. The diagnosis was categorized based on the SUN working group classification criteria for uveitis. Details regarding clinical features, investigations, ophthalmic treatment given, response to treatment, ocular complications, and status at last visit were also accessed. Statistical analysis of demographical data was done using Microsoft Excel 2019.Results:Twenty-one eyes of 13 patients were included in this hospital-based retrospective observational study. The study included six male and seven female patients. The mean age was 38 ± 16.8 years. Eight patients had bilateral involvement. Seven patients were diagnosed with anterior uveitis, three with intermediate uveitis, one with posterior uveitis, and two with panuveitis. All patients responded well to treatment and were doing well at their last visit. Two patients had complications that necessitated surgical treatment, following which they recovered good visual outcomes.Conclusion:With prompt diagnosis and appropriate management, all the patients with uveitis post-COVID-19 infection recovered with good visual outcomes. Thus, ophthalmologists must be aware of the possible uveitic manifestations following even uneventful COVID-19 infection.  相似文献   
148.
149.
Rapidly growing cities face new and compounding health challenges, leading governments and donors to seek innovative ways to support healthier, more resilient urban growth. One such approach is the systems mapping process developed by Engaging Inquiry (EI) for the USAID-funded Building Healthy Cities project (BHC) in four cities in Asia. This paper provides details on the theory and methods of the process. While systems mapping is not new, the approach detailed in this paper has been uniquely adapted to the purpose of municipal planning. Strategic stakeholder engagement, including participatory workshops with a diverse group of stakeholders, is at the core of this approach and led to deeper insights, greater buy-in, and shared understanding of the city’s unique opportunities and challenges. This innovative mapping process is a powerful tool for defining municipal priorities within growing cities across the globe, where the situation is rapidly evolving. It can be used to provide evidence-based information on where to invest to gain the biggest impact on specific goals. This paper is part of a collection in this issue providing a detailed accounting of BHC’s systems mapping approach across four project cities.  相似文献   
150.
An anatomical study of 50 fresh adult human cadavers was performed in order to verify prevalence of Galen's anastomosis (GA) and to evaluate whether factors such as gender, ethnicity, side of the neck, and individual stature may interfere with GA prevalence. The results were analysed using the Chi-square test, Student t-test, and F-Snedecor test. GA was observed in 87 of 100 dissections. There was no statistically significant difference regarding GA prevalence between groups separated by ethnicity (p = 0.853), gender (p = 0.198), side of the neck (p = 0.766), or individual height (p = 0.199). Therefore, the GA was a frequent anatomical finding, and this result was not influenced by any studied factor. Comparing our data with previous studies, we also concluded that the GA seems to play an important role in the innervation of the larynx, even though its function remains unclear. Also, it is reasonable to consider GA a constant anatomical constituent.  相似文献   
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