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Background and Objective: Although preventable, substance addiction has become one of the most prominent public health problems facing the nation. As a result, treatment programs and centers have focused resources and efforts on aiding individuals on their path to long-term recovery. However, the constant threat, reinforced by high incidence, of relapse presents a major obstacle to long-term recovery. Relapse prevention programs are designed to target social and psychological factors contributing to lapses in sobriety. Yet, the exact factors that can impact long-term recovery and prevent or lower the instances of relapse are not always clear. The current study explores the major contributors to relapse as experienced in a male residential treatment center.

Methods: The data were gathered through 31 in-depth interviews in a residential halfway house treatment facility for substance use recovery.

Results: The results of the study underscored social support and interpersonal relationships as major factors impacting long-term recovery. More specifically, lack of efficacy in managing interpersonal relationships and building new support networks were identified as essential barriers to long-term recovery.

Conclusions: The management of interpersonal relationships seems to be a key to long-term recovery, which emphasizes the need for strategies that underscore the development of positive relationships that will strengthen resistance to relapse and long-term recovery.  相似文献   

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Introduction

Intrathecal chemoprophylaxis is often administered to patients with diffuse large B-cell lymphoma (DLBCL) to lower the rates of central nervous system (CNS) relapse, although its benefit has not been well-described. Prognostic models, including the CNS-International Prognostic Index (IPI), have been developed to aid in identifying patients at highest risk for CNS relapse.

Patients and Methods

We evaluated 112 patients diagnosed with DLBCL from 2009 to 2016 at Emory Healthcare and classified them as high (n = 44) or low risk (n = 68) for CNS relapse and compared CNS prophylaxis rates and relapse rates between groups. The primary outcome was to compare the CNS relapse rate in high-risk patients who received intrathecal prophylaxis with patients who did not.

Results

Twenty-six patients (14 high-risk and 12 low-risk) received intrathecal prophylaxis. Only 4 of 112 patients experienced a CNS relapse, including 1 in the high-risk group and 3 in the low-risk group. Among 14 high-risk patients who received intrathecal prophylaxis, no patient experienced CNS relapse compared with 1 of 30 high-risk patients without prophylaxis (P = 1.0).

Conclusion

Given the low rates of CNS relapse in this series, it is difficult to discern the impact of current risk stratification combined with intrathecal prophylaxis on outcomes. Our observation that many high-risk patients did not receive prophylaxis, whereas many low-risk patients received prophylaxis emphasizes the need for a standardized approach.  相似文献   
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Background: Breast cancer is a multifactorial disease that affects women worldwide. Its progression is likely to be executed by oxidative stress wherein elevated levels of reactive oxygen and nitrogen species drive several breast cancer pathologies. Spider venom contains various pharmacological peptides which exhibit selective activity to abnormal expression of ion channels on cancer cell surface which can confer potent anti-cancer activities against this disease. Methods: Venom was extracted from a Philippine tarantula by electrostimulation and fractionated by reverse phase-high performance liquid chromatography (RP-HPLC). Venom fractions were collected and used for in vitro analyses such as cellular toxicity, morphological assessment, and oxidative stress levels. Results: The fractionation of crude spider venom generated several peaks which were predominantly detected spectrophotometrically and colorimetrically as peptides. Treatment of MCF-7 cell line of selected spider venom peptides induced production of several endogenous radicals such as hydroxyl radicals (•OH), nitric oxide radicals (•NO), superoxide anion radicals (•O2−) and lipid peroxides via malondialdehyde (MDA) reaction, which is comparable with the scavenging effects afforded by 400 µg/mL vitamin E and L-cysteine (p<0.05). Concomitantly, the free radicals produced decrease the mitochondrial membrane potential and metabolic activity as detected by rhodamine 123 and tetrazolium dye respectively (p>0.05). This is manifested by cytotoxicity in MCF-7 cells as seen by increase in membrane blebbing, cellular detachment, caspase activity and nuclear fragmentation. Conclusion: These data suggest that the Philippine tarantula venom contains peptide constituents exhibiting pro-oxidative and nitrosative-dependent cytotoxic activities against MCF-7 cells and can indicate mechanistic insights to further explore its potential application as prooxidants in cancer therapy.  相似文献   
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Bilayer hydrogels with a soft cartilage‐like layer and a stiff bone‐like layer embedded with human mesenchymal stem cells (hMSCs) are promising for osteochondral tissue engineering. The goals of this work were to evaluate the effects of dynamic compressive loading (2.5% applied strain, 1 Hz) on osteogenesis in the stiff layer and spatially map local mechanical responses (strain, stress, hydrostatic pressure, and fluid velocity). A bilayer hydrogel was fabricated from soft (24 kPa) and stiff (124 kPa) poly (ethylene glycol) hydrogels. With hMSCs embedded in the stiff layer, osteogenesis was delayed under loading evident by lower OSX and OPN expressions, alkaline phosphatase activity, and collagen content. At Day 28, mineral deposits were present throughout the stiff layer without loading but localized centrally and near the interface under loading. Local strains mapped by particle tracking showed substantial equivalent strain (~1.5%) transferring to the stiff layer. When hMSCs were cultured in stiff single‐layer hydrogels subjected to similar strains, mineralization was inhibited. Finite element analysis revealed that hydrostatic pressures ≥~600 Pa correlated to regions lacking mineralization in both hydrogels. Fluid velocities were low (~1–10 nm/s) in the hydrogels with no apparent correlation to mineralization. Mineralization was recovered by inhibiting ERK1/2, indicating cell‐mediated inhibition. These findings suggest that high strains (~1.5%) combined with higher hydrostatic pressures negatively impact osteogenesis, but in a manner that depends on the magnitude of each mechanical response. This work highlights the importance of local mechanical responses in mediating osteogenesis of hMSCs in bilayer hydrogels being studied for osteochondral tissue engineering.  相似文献   
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