97 research outputs found
Interaction of Retinol with HSA using Spectroscopic Techniques
The interaction between retinol and HSA has been investigated using UV-absorption spectrophotometry, fluorescence
spectroscopy and Fourier Transform Infrared (FT-IR) spectroscopy.UV-absorption spectrophotometry showed an increase in the
absorption intensity with increasing the molecular ratios of retinol to HSA, it is found that the value of the binding constant is estimated
to be1.7176×102 M-1. FTIR spectroscopy is used in the mid infrared region with Fourier self deconvolution, second derivative, difference
spectra, peak picking and curve fitting were used to determine the effect of Retinol on the protein secondary structure in the amides I, II
and Ill regions. Analysis of FTIR absorbance spectra is found that the intensity of the absorption bands increased with increasing the
molecular ratios of retinol, however from the deconvoluted and curve fitted spectra found that the absorbance intensity for α-helix
decreases relative to β-sheets, this decrease in intensity is related to the formation of H- bonding in the complex molecules
Comparative studies on the interactions between human serum albumin, bovine serum albumin and cholesterol: ftir and fluorescence spectroscopy
The interaction of the human serum albumin (HSA), bovine serum albumin (BSA) with cholesterol has
been investigated. The basic binding interaction was studied by FTIR and fluorescence spectroscopy.
From spectral analysis cholesterol showed a strong ability to quench the intrinsic fluorescence of HSA
and BSA through a static quenching mechanism. The binding constant (k) between HSA and cholesterol
is estimated to be K=2.14 × 103 M-1 at 293 K while between BSA and cholesterol is estimated to be
K=.1.12 × 103 M-1 at the same temperature. FTIR spectroscopy with Fourier self-deconvolution technique
was used to determine the protein secondary structure and cholesterol binding mechanisms. The observed
spectral changes indicate a higher percentage of H-bonding between cholesterol and -helix compared to
the percentage of H-bonding to cholesterol and -sheets.This work is supported by the German
Research Foundation DFG grant No. DR228/24-
Study of Progesterone interaction with Human Serum Albumin: Spectroscopic approach
The interaction between progesterone and human serum albumin has been investigated. This interaction was studied by UV-absorption and fluorescence spectroscopy. From spectral analysis progesterone showed a strong ability to quench the intrinsic fluorescence of HSA through a static quenching procedure. The binding constant (K) is estimated 6.56×102 M-1 at 293 K. FT-IR spectroscopy with Fourier self-deconvolution technique was used to determine HSA secondary structure and progesterone binding mechanisms. The observed spectral changes indicate the formation of H-bonding between progesterone and HSA molecules which can be related to the intensity decrease in the absorption band of α-helix relative to that of β-sheets.This work is supported by the German Research Foundation DFG grant No. DR228/24-
Spectroscopic approach of the interaction study of Ceftriaxone and human serum albumin
Under physiological conditions, interaction between ceftriaxone and human serum albumin was
investigated by using fluorescence spectroscopy and ultra violet (UV) absorption spectrum. From
spectral analysis, ceftriaxone showed a strong ability to quench the intrinsic fluorescence of human
serum albumin (HSA) through a static quenching procedure. The binding constant (k) is estimated as
K=1.02× 103 M-1 at 298 K. Fourier transform infrared spectroscopy (FT-IR) spectroscopy with Fourier
self-deconvolution technique was used to determine the protein secondary structure and drug binding
mechanisms. The observed spectral changes indicated the formation of H-bonding between ceftriaxone
and HSA molecules at higher percentage for -helix than for the -sheets.This work was supported by the German Research Foundation DFG Grant No. DR228/24-2
Augmenter of liver regeneration
‘Augmenter of liver regeneration’ (ALR) (also known as hepatic stimulatory substance or hepatopoietin) was originally found to promote growth of hepatocytes in the regenerating or injured liver. ALR is expressed ubiquitously in all organs, and exclusively in hepatocytes in the liver. ALR, a survival factor for hepatocytes, exhibits significant homology with ERV1 (essential for respiration and viability) protein that is essential for the survival of the yeast, Saccharomyces cerevisiae. ALR comprises 198 to 205 amino acids (approximately 22 kDa), but is post-translationally modified to three high molecular weight species (approximately 38 to 42 kDa) found in hepatocytes. ALR is present in mitochondria, cytosol, endoplasmic reticulum, and nucleus. Mitochondrial ALR may be involved in oxidative phosphorylation, but also functions as sulfhydryl oxidase and cytochrome c reductase, and causes Fe/S maturation of proteins. ALR, secreted by hepatocytes, stimulates synthesis of TNF-α, IL-6, and nitric oxide in Kupffer cells via a G-protein coupled receptor. While the 22 kDa rat recombinant ALR does not stimulate DNA synthesis in hepatocytes, the short form (15 kDa) of human recombinant ALR was reported to be equipotent as or even stronger than TGF-α or HGF as a mitogen for hepatocytes. Altered serum ALR levels in certain pathological conditions suggest that it may be a diagnostic marker for liver injury/disease. Although ALR appears to have multiple functions, the knowledge of its role in various organs, including the liver, is extremely inadequate, and it is not known whether different ALR species have distinct functions. Future research should provide better understanding of the expression and functions of this enigmatic molecule
Twelve-month observational study of children with cancer in 41 countries during the COVID-19 pandemic
Introduction Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality. Methods Prospective cohort study in 109 institutions in 41 countries. Inclusion criteria: children <18 years who were newly diagnosed with or undergoing active treatment for acute lymphoblastic leukaemia, non-Hodgkin's lymphoma, Hodgkin lymphoma, retinoblastoma, Wilms tumour, glioma, osteosarcoma, Ewing sarcoma, rhabdomyosarcoma, medulloblastoma and neuroblastoma. Of 2327 cases, 2118 patients were included in the study. The primary outcome measure was all-cause mortality at 30 days, 90 days and 12 months. Results All-cause mortality was 3.4% (n=71/2084) at 30-day follow-up, 5.7% (n=113/1969) at 90-day follow-up and 13.0% (n=206/1581) at 12-month follow-up. The median time from diagnosis to multidisciplinary team (MDT) plan was longest in low-income countries (7 days, IQR 3-11). Multivariable analysis revealed several factors associated with 12-month mortality, including low-income (OR 6.99 (95% CI 2.49 to 19.68); p<0.001), lower middle income (OR 3.32 (95% CI 1.96 to 5.61); p<0.001) and upper middle income (OR 3.49 (95% CI 2.02 to 6.03); p<0.001) country status and chemotherapy (OR 0.55 (95% CI 0.36 to 0.86); p=0.008) and immunotherapy (OR 0.27 (95% CI 0.08 to 0.91); p=0.035) within 30 days from MDT plan. Multivariable analysis revealed laboratory-confirmed SARS-CoV-2 infection (OR 5.33 (95% CI 1.19 to 23.84); p=0.029) was associated with 30-day mortality. Conclusions Children with cancer are more likely to die within 30 days if infected with SARS-CoV-2. However, timely treatment reduced odds of death. This report provides crucial information to balance the benefits of providing anticancer therapy against the risks of SARS-CoV-2 infection in children with cancer
Survival rate among children with acute lymphoblastic leukemia based on their relapse status in Shiraz Shahid Faghihi hospital during 2004-9
Background: Relapse in leukemic patients is considered as a major cause of treatment failure and a decrease in patient survival rate. This study was conducted to determine the survival rate of patients with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) based on their relapse status.Materials and Methods: This retrospective cohort study was performed on a total of 243 cases of leukemia aged less than 15 years in Shiraz Shahid Faghihi hospital. Data were analyzed using Kaplan-Meier method, log-rank test and Cox regression model.Results: The 1- and 5-year survival rates for patients without relapsed leukemia were 96.9 and 76.9 and for relapsed leukemia were 82.4 and 28.6, respectively. Therefore, there was a significant relationship between the relapse occurrence and survival rate among the patients (P=0.001). Conclusion: The relapse occurrence is one of the main effective factors in survival rate of leukemic patients a five-year survival rate in the patients is less than 30 percent in this center
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