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2.
Am J Transplant ; 14(8): 1853-61, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25039276

ABSTRACT

Over the past two decades, live kidney donation by older individuals (≥55 years) has become more common. Given the strong associations of older age with cardiovascular disease (CVD), nephrectomy could make older donors vulnerable to death and cardiovascular events. We performed a cohort study among older live kidney donors who were matched to healthy older individuals in the Health and Retirement Study. The primary outcome was mortality ascertained through national death registries. Secondary outcomes ascertained among pairs with Medicare coverage included death or CVD ascertained through Medicare claims data. During the period from 1996 to 2006, there were 5717 older donors in the United States. We matched 3368 donors 1:1 to older healthy nondonors. Among donors and matched pairs, the mean age was 59 years; 41% were male and 7% were black race. In median follow-up of 7.8 years, mortality was not different between donors and matched pairs (p = 0.21). Among donors with Medicare, the combined outcome of death/CVD (p = 0.70) was also not different between donors and nondonors. In summary, carefully selected older kidney donors do not face a higher risk of death or CVD. These findings should be provided to older individuals considering live kidney donation.


Subject(s)
Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/mortality , Kidney Transplantation , Living Donors , Renal Insufficiency/surgery , Age Factors , Aged , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Medicare , Middle Aged , Nephrectomy , Quality of Life , Time Factors , Treatment Outcome , United States
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 57(8): 1541-53, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11471706

ABSTRACT

Solvatochromic studies on quinoline (Q), 3-cyanoquinoline (CNQ), 3-bromoquinoline (BrQ) and 8-hydroxyquinoline (OHQ) in pure solvents and alcohol-cyclohexane mixtures have been performed. The results are compared with Proton Nuclear Magnetic Resonance, 1H NMR. studies and AMI calculations. Taft and Kamlet's solvatochromic comparison method was used to disclose solvent effects in pure solvents. These studies shows that the hydrogen bond acceptor ability of the Q ring is diminished and its polarity is increased by the presence of the cyano group in CNQ and the bromo group in BrQ. In OHQ, intramolecular hydrogen bonding has been observed. This interaction is weakened by the interaction with protic solvents. The studies in binary mixtures, alcohol-cyclohexane, show solute-solvent interactions, which compete with solvent self-association in the preferential solvation phenomena. Alcohols with strong ability to self-associate have less preference toward solvation of these compounds. The association constants for solute-ethanol systems were determined by 1H NMR. The results show that the solvent hydrogen bond donor ability is the main factor involved in the interaction with these solutes at the aza aromatic site.


Subject(s)
Quinolines/chemistry , Hydrogen Bonding , Magnetic Resonance Spectroscopy/methods , Solvents , Spectrophotometry, Ultraviolet/methods
4.
Photochem Photobiol ; 74(1): 14-21, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11460532

ABSTRACT

The photodynamic activities of the free-base 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin (TMP) and their metal complexes with zinc(II) (ZnTMP), copper(II) (CuTMP) and cadmium(II) (CdTMP) have been compared in two systems: reverse micelle of n-heptane/sodium bis(2-ethylhexyl)sulfosuccinate/water bearing photooxidizable substrates and Hep-2 human larynx carcinoma cell line. The quantum yields of singlet molecular oxygen, O2(1 delta g), production (phi delta) of TMP, ZnTMP and CdTMP in tetrahydrofuran, were determined yielding values of 0.65, 0.73 and 0.73, respectively, while O2(1 delta g) formation was not detected for CuTMP. In the reverse micellar system, the amino acid L-tryptophan (Trp) was used as biological substrate to analyze the O2(1 delta g)-mediated photooxidation. The observed rate constants for Trp photooxidation (kobsTrp) were proportional to the sensitizer quantum yield of O2(1 delta g). A value of approximately 2 x 10(7) s-1 M-1 was found for the second-order rate constant of Trp (krTry) in this system. The response of Hep-2 cells to cytotoxicity photoinduced by these agents in a biological medium was studied. The Hep-2 cultures were treated with 1 microM of porphyrin for 24 h at 37 degrees C and the cells exposed to visible light. The cell survival at different light exposure levels was dependent on phi delta. Under these conditions, the cytotoxic effect increases in the order: Cu-TMP << TMP < ZnTMP approximately CdTMP, correlating with the production of O2(1 delta g). A similar behavior was observed in both the chemical and biological media indicating that the O2(1 delta g) mediation appears to be mainly responsible for the cell inactivation.


Subject(s)
Porphyrins/pharmacology , Cell Survival/drug effects , Humans , Oxygen/metabolism , Photochemistry , Photochemotherapy , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Porphyrins/chemistry , Singlet Oxygen , Tumor Cells, Cultured
5.
Spine (Phila Pa 1976) ; 26(24 Suppl): S111-8, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11805617

ABSTRACT

There are approximately 50,000 fractures to the bony spinal column each year in the United States. The vast majority of unstable spinal injuries are recognized early and managed appropriately. Rarely, the initial treatment may have been inadequate, or in less obvious injuries, less aggressive immobilization techniques may have been chosen. This along with continued exposure to physiologic stresses may lead to a gradual post-traumatic deformity that may further impede the functional as well as emotional status of these often already compromised patients. The management of post-traumatic deformity can be extremely challenging. A post-traumatic kyphotic deformity may occur in the cervical, thoracic, thoracolumbar, or lumbar spine, and once appropriate imaging studies are obtained, careful surgical considerations must be undertaken. Surgical intervention is considered if the kyphotic deformity is progressive over time or there is new onset or progression of a neurologic deficit. Surgical procedures include either a posterior or anterior only approach or any variation of a combined anterior or posterior procedure. In most cases a posterior only fusion is often insufficient for optimal correction and stabilization. Although the majority of patients developing a post-traumatic deformity usually occur after spinal column trauma initially treated nonoperatively, several miscellaneous causes of post-traumatic deformity may occur after surgery. These include nonunion, implant failure, Charcot spine, and technical error. The overall outcome after the surgical management of post-traumatic deformity has been satisfactory with better outcomes in the patients treated earlier as opposed to later. Operative complications include the increased risk of neurologic injury because of the draping of the neural elements over the anterior vertebral elements, any pre-existing spinal cord injury, and possible scarring with cord tethering. Trauma to the spinal cord and column is a devastating injury that may be fraught with many complications including post-traumatic deformity. Certainly, the best treatment is prevention with close follow-up and early intervention when needed. Once present, the treatment of post-traumatic deformity follows basic biomechanical principles consisting of re-establishing the integrity of the compromised spinal columns so that spinal stability can be restored.


Subject(s)
Kyphosis/etiology , Spinal Injuries/complications , Diagnostic Imaging , Humans , Kyphosis/surgery , Pain/etiology , Risk Factors , Scoliosis/etiology , Scoliosis/surgery , Spinal Fractures/complications , Spinal Injuries/diagnosis , Spinal Injuries/epidemiology , Spinal Injuries/surgery
6.
J Clin Oncol ; 10(12): 1879-88, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1453203

ABSTRACT

PURPOSE: More than 95% of children with B-lineage acute lymphoblastic leukemia (ALL) achieve a clinical remission after the induction phase of chemotherapy (first 28 days) as evaluated by morphologic criteria. However, relapse occurs in approximately 30% of these children. The objective of this study was to determine whether the outcome of patients in clinical remission at the end of induction therapy could be predicted using a highly sensitive method to detect residual disease. PATIENTS AND METHODS: All children diagnosed with B-lineage ALL at the Children's Hospital of Philadelphia during a 2-year period were eligible. The extent of residual leukemia was quantitated in remission marrow samples obtained at the end of induction therapy in 44 children using a phage clonogenic assay in association with complementarity-determining-region 3 (CDR3)-polymerase chain reaction (PCR). RESULTS: Residual disease was a significant predictor of outcome independent of WBC count, age, or sex. The estimated relapse-free survival (RFS) during therapy was 50.4% (+/- 12.6%) for patients with high residual disease (> or = 0.6% leukemia cells among total marrow B cells) versus 91.9% (+/- 5.5%) for those with lower levels (P < .002). There were no significant differences in off-treatment RFS between patients with high or low residual disease who completed therapy in continuous remission (P = .82). The overall estimated RFS was 32.3% (+/- 11.6%) for patients with high residual disease versus 62.6% (+/- 10.7%) for patients with lower levels of residual leukemia cells, with a median follow-up of 5.3 years for patients in continuous remission (P < .008). CONCLUSION: PCR detection of high residual disease at the end of induction therapy identifies patients at increased risk for relapse during therapy.


Subject(s)
Burkitt Lymphoma/pathology , Burkitt Lymphoma/therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male , Predictive Value of Tests , Recurrence , Regression Analysis , Remission Induction , Survival Analysis , Treatment Outcome
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