20 research outputs found
Asymmetric Hydrogenation in Water by a Rhodium Complex of Sulfonated 2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl (binap)
The synthesis of sulfonated 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (binap) is reported; a rhodium complex of this ligand is the first to perform asymmetric hydrogenation in neat water with optical yields as high as those obtained in nonaqueous solvent
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Minimal clinically important difference of the EORTC QLQ-CIPN20 for worsening peripheral neuropathy in patients receiving neurotoxic chemotherapy.
Context/objectivesThis is the first study to determine the minimal clinically important difference (MCID) of the European Organisation of Research and Treatment of Cancer Quality of Life Questionnaire-CIPN twenty-item scale (EORTC QLQ-CIPN20), a validated instrument designed to elicit cancer patients' experience of symptoms and functional limitations related to chemotherapy-induced peripheral neuropathy.MethodsCancer patients receiving neurotoxic chemotherapy completed EORTC QLQ-CIPN20 and the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity [FACT/GOG-NTX] at baseline, second cycle of chemotherapy (T2, n = 287), and 12 months after chemotherapy (T3, n = 191). Anchor-based approach used the validated FACT/GOG-NTX neurotoxicity (Ntx) subscale to identify optimal MCID cutoff for deterioration. Distribution-based approach used one-third standard deviation (SD), half SD, and one standard error of measurement of the total EORTC QLQ-CIPN20 score.ResultsThere was a moderate correlation between the change scores of the Ntx subscale and sensory and motor subscales of QLQ-CIPN20 (T2: r = - 0.722, p < 0.001 and r = - 0.518, p < 0.001, respectively; T3: r = - 0.699; p < 0.001 and r = - 0.523, p < 0.001, respectively). The correlation between the change scores of the Ntx subscale and the QLQ-CIPN20 autonomic subscale was poor (T2: r = - 0.354, p < 0.001; T3: r = 0.286, p < 0.001). Based on the MCID derived using distribution-based method, the MCID for the QLQ-CIPN20 sensory subscale was 2.5-5.9 (6.9% to 16.4% of the subdomain score) and for motor subscale was 2.6-5.0 (8.1%-15.6% of the subdomain score).ConclusionThe MCID for the EORTC QLQ-CIPN20 established using distribution-based approaches was 2.5-5.9 for the sensory subscale and 2.6-5.0 for the motor subscale. When noted in assessments even with small change in scores, clinicians can be alerted for appropriate intervention
An Epstein-Barr virus–encoded microRNA targets PUMA to promote host cell survival
Epstein-Barr virus (EBV) is a herpesvirus associated with nasopharyngeal carcinoma (NPC), gastric carcinoma (GC), and other malignancies. EBV is the first human virus found to express microRNAs (miRNAs), the functions of which remain largely unknown. We report on the regulation of a cellular protein named p53 up-regulated modulator of apoptosis (PUMA) by an EBV miRNA known as miR-BART5, which is abundantly expressed in NPC and EBV-GC cells. Modulation of PUMA expression by miR-BART5 and anti–miR-BART5 oligonucleotide was demonstrated in EBV-positive cells. In addition, PUMA was found to be significantly underexpressed in ∼60% of human NPC tissues. Although expression of miR-BART5 rendered NPC and EBV-GC cells less sensitive to proapoptotic agents, apoptosis can be triggered by depleting miR-BART5 or inducing the expression of PUMA. Collectively, our findings suggest that EBV encodes an miRNA to facilitate the establishment of latent infection by promoting host cell survival
Immunoregulatory Protein Profiles of Necrotizing Enterocolitis versus Spontaneous Intestinal Perforation in Preterm Infants
Necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP) are the most common acute surgical emergencies associated with high morbidity and mortality in preterm infants. We aimed to compare the profiles of immunoregulatory proteins and identify novel mediators in plasma of NEC and SIP infants. We also investigated the expression of target genes in resected intestinal tissues and an enterocyte cell line. Using Cytokine Antibody Array assay, we reported the first comparative profiles of immunoregulatory proteins in plasma of NEC and SIP infants, and showed that dysregulated proteins belonged to functionally diversified categories, including pro- and anti-inflammation, angiogenesis, cell growth, wound healing, anti-apoptosis, cell adhesion and extracellular matrix reorganization. Validation by ELISA confirmed significantly higher concentrations of interleukin (IL)-6, angiopoietin (Ang)-2, soluble type II interleukin-1 receptor (sIL-1RII), and soluble urokinase-type plasminogen activator receptor (suPAR) in NEC infants compared with gestational age-matched control, and a lower level of an epidermal growth factor receptor, secreted form of receptor tyrosine-protein kinase ErbB3 (sErbB3), compared with SIP infants. mRNA expressions of IL1-RII and uPAR were up-regulated in resected bowel tissues from NEC infants, indicating that immunoregulation also occurred at the cellular level. In FHs-74 Int cells, Ang-2, IL1-RII and uPAR mRNA expressions were significantly induced by the combined treatment with lipopolysaccharide (LPS) and platelet activating factor (PAF). Our study provided plasmatic signatures of immunoregulatory proteins in NEC and SIP infants, and demonstrated involvement of multiple functional pathways. The magnitude of changes in these proteins was significantly more extensive in NEC infants, reflecting the different nature of injury and/or severity of inflammation. We speculate that dysregulation of IL-6, Ang-2, IL-1RII and uPAR occurred at both systemic and cellular levels, and probably mediated via LPS and endogeneous PAF signals. Such exaggerated immunologic responses may account for the high morbidity and mortality in NEC compared with SIP patients
The Design and Synthesis of a True, Heterogeneous, Asymmetric Catalyst
This work describes the design and synthesis of a true, heterogeneous,
asymmetric catalyst. The catalyst consists of a thin film that resides on a high-surface-
area hydrophilic solid and is composed of a chiral, hydrophilic
organometallic complex dissolved in ethylene glycol. Reactions of prochiral
organic reactants take place predominantly at the ethylene glycol-bulk organic
interface.
The synthesis of this new heterogeneous catalyst is accomplished in a
series of designed steps. A novel, water-soluble, tetrasulfonated 2,2'-bis
(diphenylphosphino)-1,1'-binaphthyl (BINAP-4S0_3Na) is synthesized by
direct sulfonation of 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (BINAP).
The rhodium (I) complex of BINAP-4SO_3Na is prepared and is shown to be
the first homogeneous catalyst to perform asymmetric reductions of prochiral
2-acetamidoacrylic acids in neat water with enantioselectivities as high as
those obtained in non-aqueous solvents. The ruthenium (II) complex,
[Ru(BINAP-4SO_3Na)(benzene)Cl]Cl is also synthesized and exhibits a broader
substrate specificity as well as higher enantioselectivities for the homogeneous
asymmetric reduction of prochiral 2-acylamino acid precursors in water.
Aquation of the ruthenium-chloro bond in water is found to be detrimental to
the enantioselectivity with some substrates. Replacement of water by ethylene
glycol results in the same high e.e's as those found in neat methanol. The
ruthenium complex is impregnated onto a controlled pore-size glass CPG-240 by the incipient wetness technique. Anhydrous ethylene glycol is used as the
immobilizing agent in this heterogeneous catalyst, and a non-polar 1:1
mixture of chloroform and cyclohexane is employed as the organic phase.
Asymmetric reduction of 2-(6'-methoxy-2'-naphthyl)acrylic acid to the
non-steroidal anti-inflammatory agent, naproxen, is accomplished with this
heterogeneous catalyst at a third of the rate observed in homogeneous
solution with an e.e. of 96% at a reaction temperature of 3°C and 1,400 psig of
hydrogen. No leaching of the ruthenium complex into the bulk organic phase
is found at a detection limit of 32 ppb. Recycling of the catalyst is possible
without any loss in enantioselectivity. Long-term stability of this new
heterogeneous catalyst is proven by a self-assembly test. That is, under the
reaction conditions, the individual components of the present catalytic system
self-assemble into the supported-catalyst configuration.
The strategies outlined here for the design and synthesis of this new
heterogeneous catalyst are general, and can hopefully be applied to the
development of other heterogeneous, asymmetric catalysts. </p
Syntheses and photochemistry of monomeric platinum (II) complexes
published_or_final_versionChemistryMasterMaster of Philosoph
Reactions of meta-xylene on zeolites with intersecting medium and large pores I. Basic studies
The reactions of m-xylene are conducted over all known zeolites with intersecting medium and large pores (MCM-22, NU-87, CIT-1, SSZ-33, SSZ-26) and the results compared to those from large (SSZ-24, ZSM-12, zeolite beta, zeolite L) and medium (ZSM-5, EU-1) pore zeolites. Each of the materials MCM-22, NU-87 and CIT-1/SSZ-33/SSZ-26 reveals a unique reaction behavior in terms of the p-xyleneo-xylene and isomerization/disproportionation ratios, the distribution of formed trimethylbenzenes and the rate of deactivation. The reaction activities and selectivities of MCM-22 and CIT-1/SSZ-33/SSZ-26 are somewhat like medium and large pore zeolites, respectively, as is expected from their crystal structures. NU-87 displays a lower p-xyleneo-xylene ratio and a higher turnover frequency than predicted from the crystal structure
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Risk factors for chemotherapy-induced peripheral neuropathy in patients receiving taxane- and platinum-based chemotherapy.
BackgroundChemotherapy-induced peripheral neuropathy (CIPN) is a significant and difficult to manage side effect of neurotoxic chemotherapies. Several risk factors for CIPN have been identified to date, but inconsistencies and methodological limitations exist in past research. Also, a limited number of potential risk factors has been investigated in the past.AimThe objective of this study was to assess the relative contribution of a wider range of risk factors in the development of CIPN.MethodsThis analysis used the 6-month data after starting chemotherapy from a larger prospective observational study on CIPN risk, prevalence, and quality of life. Patients were assessed at recruitment for possible CIPN risk factors, including prior history of neuropathies, current/past infectious diseases; neurotoxic medication history; personal and treatment characteristics; smoking history, alcohol use, and vegetable/fruit intake. Neuropathy was assessed at 6-months after starting chemotherapy with the neuropathy (motor/sensory) items of the NCI-CTCAE scale and the WHO criterion for neuropathy. Data on symptom burden were also collected.ResultsData were available from 255 patients from three cancer centers in Hong Kong, Singapore, and UK. The use of different scales did not always identify the same predictor variables. Key risk factors in multivariate regression models included older age (highest OR = 1.08, p < 0.01 with the WHO scale), chemotherapy (platinum-based chemotherapy had OR = 0.20-0.27 in developing CIPN compared to taxane-based chemotherapy), history of neuropathy (for motor CIPN only, OR = 8.36, p < 0.01), symptom burden (OR = 1.06, p < 0.05), number of chemotherapy cycles received (OR = 1.19-1.24, p < 0.01), and alcohol intake (OR = 0.32, p < 0.05). In univariate analysis, the use of statins was implicated with CIPN (p = 0.03-0.04 with different assessments) and diabetes showed a trend (p = 0.09) in the development of CIPN.ConclusionThis study confirmed the CIPN risk related to certain variables and identified new ones. This knowledge can assist with treatment decisions and patient education
Risk factors for chemotherapy-induced peripheral neuropathy in patients receiving taxane- and platinum-based chemotherapy
201906 bcrcVersion of RecordPublishe
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Psychometric testing of the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) subscale in a longitudinal study of cancer patients treated with chemotherapy.
BackgroundThe aim of this study was to evaluate the psychometric properties of the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) subscale in a longitudinal study of cancer patients treated with chemotherapy.MethodsPatients were assessed with the FACT/GOG-Ntx subscale, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Chemotherapy-Induced Peripheral Neuropathy Scale 20 (EORTC QLQ-CIPN20), National Cancer Institute -Common Terminology Criteria for Adverse Events (NCI-CTCAE), and light touch test using 10 g monofilament for up to ten assessment points from baseline (prior to initiation of first chemotherapy), after the end of each cycle (up to 6 cycles, 3 weeks per cycle), and at 6, 9, and 12 months after starting chemotherapy. Psychometric analyses included internal consistency reliability, convergent validity, factorial validity, sensitivity to change and responsiveness (minimal clinically important difference, MCID).ResultsCronbach's alpha coefficients of the FACT/GOG-Ntx subscale were 0.82-0.89 across assessment points. The subscale strongly correlated with the EORTC QLQ-CIPN20 (r = 0.79-0.93) but low-to-moderately correlated with the NCI-CTCAE sensory (rs = 0.23-0.45) and motor items (rs = 0.15-0.50) as well as the monofilament test (rs = 0.23-0.47). The hypothesized 4-factor structure of the FACT/GOG-Ntx subscale was not confirmed at assessment points (χ2/df = 2.26-8.50; all P < 0.001). The subscale exhibited small-to-moderate sensitivity to change (r = 0.17-0.37). The MCIDs were between 1.38 and 3.68.ConclusionThe FACT/GOG-Ntx subscale has satisfactory reliability, validity, sensitivity to change and responsiveness to evaluate CIPN in cancer patients. Future research is needed to explore the factorial structure of the FACT/GOG-Ntx subscale as the published four-factor structure was not supported in this study