scholarly journals Preparation and Preliminary Evaluation of Novel β-Cyclodextrin/IUDR Prodrug Formulations

2008 ◽  
Vol 11 (2) ◽  
pp. 32 ◽  
Author(s):  
Leonard I. Wiebe ◽  
Xiao-Hong Yang ◽  
Shradha Singh ◽  
Jim Diakur
Keyword(s):  
Inclusion Complexes ◽  
In Vivo Studies ◽  
Preliminary Evaluation ◽  
Target Tissue ◽  
Molar Ratios ◽  
Nmr Spectrometry ◽  
Complex Approach ◽  
The Stability

PURPOSE. Iododeoxyuridine (IUdR) has a very short in vivo half-life and consequently achieves low target-tissue concentrations with concomitant lower efficacy than would be predicted from in vitro studies. This work reports the preparation of IUdR:?-cyclodextrin (?-CyD) inclusion complexes designed to reduce in vivo inactivation of IUdR. METHODS. IUdR was derivatized with either 1-adamantanecarbonyl chloride or 4-(1-adamantyl-carbamoyl)butanoic acid, to prepare 5’-O-(1-adamantoyl)-5-iodo-2’-deoxyuridine 1 and 5’-O-(4-(1-adamantylcarbamoyl)butoyl)-5-iodo-2’-deoxy-uridine 4, respectively. ?-CyD complexes 5 and 6 were formed by vigorous stirring of 1:1 solutions of ?-CyD and 1 or 4, respectively, in D2O under argon. Complexation was inferred from DSC, powder x-ray diffractometry and NMR spectrometry. The dissociation of 5 in water and under cholesterol challenge, and the effect of complexation on the stability of 1 was determined by incubation in plasma. RESULTS. IUdR coupling with adamantanecarbonyl chloride proceeded smoothly to afford 1 (69 %) and the di-substituted derivative, 3’,5’-di-O-(1-adamantoyl)-5-iodo-2’-deoxyuridine 2 (8 %); 4 was obtained in 42 % yield. The formation of 1:1 complexes 5 and 6 was inferred from NMR chemical shift data. In serum, 1 was 90 % hydrolyzed to IUdR in 30 min, compared to 10 % hydrolysis of 1 to IUdR when from complex 5. CONCLUSIONS. Inclusion complexes were formed between ?-CyD and adamantamine-IUdR conjugates at 1:1 molar ratios. The complex 5 was resistant to dissociation by cholesterol challenge, and 5 was more slowly converted to IUdR than non-complexed 1. In vivo studies are required to further exploit the ?-CyD inclusion complex approach for improved delivery of nucleoside derivatives.

scholarly journals The behaviour of thiomolybdates in in vitro systems

1979 ◽  
Vol 41 (2) ◽  
pp. 403-405 ◽  
Author(s):  
K. M. Weber ◽  
D. D. Leaver ◽  
A. G. Wedd
Keyword(s):  
Copper Metabolism ◽  
Hydrogen Ion ◽  
In Vivo Studies ◽  
In Vitro Systems ◽  
The Stability

The stability of potassium tetrathiomolybdate was studied in vitro using solutions with molybdenum, hydrogen ion and phosphate concentrations similar to those normally found in the rumen. Under these conditions K2[MoS4] hydrolysed rapidly and as a result the solution contained [MoS4]2−, [MoOS3]2−, [MoO2S2]2−, [HS]− and H2S in equilibrium. In view of this hydrolysis, in vivo studies of thiomolybdate on copper metabolism of sheep should not exclude the possibility that either sulphide or molybdate is responsible for any observed effect.

Preparation and Preliminary Evaluation of 68 Ga-Acridine: An Attempt to Study the Potential of Radiolabeled DNA Intercalator as a PET Radiotracer for Tumor Imaging

2020 ◽  
Vol 20 (13) ◽  
pp. 1538-1547 ◽  
Author(s):  
Subhajit Ghosh ◽  
Tapas Das ◽  
Shishu K. Suman ◽  
Haladhar D. Sarma ◽  
Ashutosh Dash
Keyword(s):  
Radiochemical Purity ◽  
Tumor Imaging ◽  
Raji Cell ◽  
Biological Behavior ◽  
Preliminary Evaluation ◽  
Dna Intercalator ◽  
Tumor Accumulation ◽  
The Stability

Introduction: Acridine is a well-known DNA intercalator and thereby gets easily inserted within DNA. As uncontrolled rapid cell division is one of the primary characteristics of the tumors, it is expected that acridine or its suitable derivatives will have preferential accumulation in the tumorous lesions. Therefore, an attempt was made to radiolabel an acridine derivative with 68Ga and study the potential of the 68Ga-acridine complex as a PET agent for tumor imaging. Methods: 9-aminoacridine was coupled with p-NCS-benzyl-DOTA to render it suitable for labeling with 68Ga. The purified acridine-DOTA conjugate was radiolabeled with 68Ga, eluted from a 68Ge/68Ga radionuclide generator. Various radiolabeling parameters were optimized and the stability of the radiolabeled preparation was studied. The biological behavior of the 68Ga-acridine complex was studied both in vitro and in vivo using Raji cell line and fibrosarcoma tumor bearing Swiss mice, respectively. Results: 68Ga-acridine complex was obtained with ~100% radiochemical purity under the optimized reaction conditions involving incubation of 2mg/mL of ligand at 100°C for 30 minutes. The complex maintained a radiochemical purity of >95% in normal saline and >65% in human blood serum at 3h post-incubation. In vitro cellular study showed (3.2±0.1)% uptake of the radiotracer in the Raji cells. Biodistribution study revealed significant tumor accumulation [(11.41±0.41)% injected activity in per gram] of the radiotracer within 1h postadministration along with uptake in other non-target organs such as, blood, liver, GIT kidney etc. Conclusion: The present study indicates the potential of 68Ga-acridine as a PET agent for imaging of tumorous lesions. However, further detailed evaluation of the agent is warranted to explore its actual potential.

Formulation and Evaluation of Fast Dissolving Gliclazide Tablets by Complexation with Hydroxypropyl-β-Cyclodextrin

2014 ◽  
Vol 7 (1) ◽  
pp. 2399-2405
Author(s):  
Adel M Aly ◽  
Khaled M. Al-Akhali ◽  
Hesham Alrefaey ◽  
Mahmoud A. Shaker
Keyword(s):  
Dissolution Rate ◽  
Spray Drying ◽  
Inclusion Complexes ◽  
In Vitro Release ◽  
Hypoglycemic Effect ◽  
Scanning Calorimetry ◽  
Molar Ratios ◽  
Market Product

Gliclazide (GZ) is practically insoluble in water and its bioavailability is limited by dissolution rate. The aim of the present study was to enhance the dissolution rate and bioavailability of GZ by complexation with hydroxypropyl (HP)-β-cyclodextrin (CD) applying three different methods; physical mixing, kneading technique and spray drying technique.  Also, to evaluate the dissolution rate and the hypoglycemic effect of the prepared complexes, in comparison with the GZ market product (Glizide tablets) in Saudi market. The produced complexes were characterized and evaluated using Differential Scanning Calorimetry (DSC), X-ray Diffractometry (XRD), Scanning Electron Microscope (SEM) and the in vitro release studies. All the methods of preparation of complexes were found to be effective in improving the solubility of gliclazide in comparison with the commercial product (Glizide tablets). The formation of inclusion complexes was evident in these formulations as shown by DSC and XRD studies. The inclusion complexes prepared by spray drying method in 1:1 molar ratios were the most effective method for improving the solubility of GZ. The in-vivo hypoglycemic effect of the complexed GZ-HP-β-CD prepared by spray drying significantly improved the biological performance and therapeutic efficacy of the drug compared to Glizide market product.  

Inclusion complexes of hydrochlorothiazide and β-cyclodextrin: Physicochemical characteristics, in vitro and in vivo studies

2016 ◽  
Vol 83 ◽  
pp. 71-78 ◽  
Author(s):  
Cassiana Mendes ◽  
Aline Buttchevitz ◽  
Jéssica H. Kruger ◽  
Jadel Müller Kratz ◽  
Cláudia Maria Oliveira Simões ◽  
...  
Keyword(s):  
Inclusion Complexes ◽  
Physicochemical Characteristics ◽  
In Vivo Studies

scholarly journals SPZ1 promotes deregulation of Bim to boost apoptosis resistance in colorectal cancer

2020 ◽  
Vol 134 (2) ◽  
pp. 155-167
Author(s):  
Xiao-Yu Liu ◽  
Chang-Bo Zheng ◽  
Teng Wang ◽  
Jian Xu ◽  
Meng Zhang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cell Growth ◽  
Clinical Stage ◽  
In Vivo Studies ◽  
Apoptosis Resistance ◽  
Advanced Clinical Stage ◽  
Helix Loop Helix ◽  
The Stability

Abstract Colorectal cancer (CRC) is the third most common malignancies in adults. Similar to other solid tumors, CRC cells show increased proliferation and suppressed apoptosis during the development and progression of the disease. Previous studies have shown that a novel tumor oncogene, spermatogenic basic helix-loop-helix transcription factor zip 1 (SPZ1), can promote proliferation. However, it is unclear whether SPZ1 plays a role in suppressing apoptosis, and the molecular mechanism behind SPZ1’s suppression of apoptosis in CRC remains unclear. Here, we found that silencing endogenous SPZ1 inhibits cell growth and induces apoptosis, and overexpression of SPZ1 promotes cell growth. These findings were corroborated by in vitro and in vivo studies. Interestingly, SPZ1 overexpressing cells were resistant to 5-fluorouracil, a drug commonly used to treat cancer. Moreover, knocking down SPZ1 led to the activation of caspase through the deregulation of Bim by ERK1/2, we found that CRC tissues had significantly higher SPZ1 and lower Bim expression, and SPZ1HBimL were associated with advanced clinical stage of CRC. Collectively, our findings demonstrate that SPZ1 contributes to tumor progression by limiting apoptosis. SPZ1 reduces apoptosis by altering the stability of Bim, suggesting SPZ1 may serve as a biomarker and therapeutic target for CRC.

scholarly journals In-Silico Evaluation of Tiryaq-E-Wabai, an Unani Formulation for its Potency against SARS-CoV-2 Spike Glycoprotein and Main Protease

2021 ◽  
Vol 11 (4-S) ◽  
pp. 86-100
Author(s):  
N ZAHEER AHMED ◽  
DICKY JOHN DAVIS ◽  
NOMAN ANWAR ◽  
ASIM ALI KHAN ◽  
RAM PRATAP MEENA ◽  
...  
Keyword(s):  
In Silico ◽  
Dynamics Simulation ◽  
In Vivo Studies ◽  
Spike Glycoprotein ◽  
Unani Medicine ◽  
Main Protease ◽  
Pubchem Database ◽  
The Stability

COVID-19 was originated in Wuhan, China, in December 2019 and has been declared a pandemic disease by WHO. The number of infected cases continues unabated and so far, no specific drug approved for targeted therapy. Hence, there is a need for drug discovery from traditional medicine. Tiryaq-e-Wabai is a well-documented formulation in Unani medicine for its wide use as prophylaxis during epidemics of cholera, plague and other earlier epidemic diseases. The objective of the current study is to generate in-silico evidence and evaluate the potency of Tiryaq-e-Wabai against SARS-CoV-2 spike (S) glycoprotein and main protease (3CLpro). The structures of all phytocompounds used in this study were retrieved from PubChem database and some were built using Marvin Sketch. The protein structure of the SARS-CoV-2 S glycoprotein and 3CLpro was retrieved from the PDB ID: 6LZG and 7BQY respectively. AutoDock Vina was used to predict top ranking poses with best scores. The results of the molecular docking showed that phytocompounds of Tiryaq-e-Wabai exhibited good docking power with spike glycoprotein and 3CLpro. Among tested compounds Crocin from Zafran and Aloin A from Sibr showed strong binding to spike glycoprotein and 3CLpro respectively. Molecular dynamics simulation confirmed the stability of the S glycoprotein-Crocin and 3CLpro-Aloin A complexes. The Unani formulation Tiryaq-e-Wabai has great potential to inhibit the SARS-CoV-2, which have to be substantiated with further in-vitro and in-vivo studies. Keywords: In-silico study, SARS-CoV-2, Tiryaq-e-Wabai, Unani formulation, Crocin, Aloin A

Dimer-tetramer transition controls RUNX1/ETO leukemogenic activity

Blood ◽  
2010 ◽  
Vol 116 (4) ◽  
pp. 603-613 ◽  
Author(s):  
Christian Wichmann ◽  
Yvonne Becker ◽  
Linping Chen-Wichmann ◽  
Vitali Vogel ◽  
Anna Vojtkova ◽  
...  
Keyword(s):  
Amino Acids ◽  
Hot Spot ◽  
Chromosomal Translocation ◽  
Structural Motif ◽  
In Vivo Studies ◽  
Tetramerization Domain ◽  
The Stability ◽  
Transplantation Model

Abstract RUNX1/ETO, the fusion protein resulting from the chromosomal translocation t(8;21), is one of the most frequent translocation products in acute myeloid leukemia. Several in vitro and in vivo studies have shown that the homo-tetramerization domain of ETO, the nervy homology region 2 (NHR2), is essential for RUNX1/ETO oncogenic activity. We analyzed the energetic contribution of individual amino acids within the NHR2 to RUNX1/ETO dimer-tetramer transition and found a clustered area of 5 distinct amino acids with strong contribution to the stability of tetramers. Substitution of these amino acids abolishes tetramer formation without affecting dimer formation. Similar to RUNX1/ETO monomers, dimers failed to bind efficiently to DNA and to alter expression of RUNX1-dependent genes. RUNX1/ETO dimers do not block myeloid differentiation, are unable to enhance the self-renewal capacity of hematopoietic progenitors, and fail to induce leukemia in a murine transplantation model. Our data reveal the existence of an essential structural motif (hot spot) at the NHR2 dimer-tetramer interface, suitable for a molecular intervention in t(8;21) leukemias.

scholarly journals THE SYNTHESIS OF 5S RNA AND ITS RELATIONSHIP TO 18S AND 28S RIBOSOMAL RNA IN THE BOBBED MUTANTS OF DROSOPHILA MELANOGASTER

Genetics ◽  
1975 ◽  
Vol 81 (4) ◽  
pp. 723-738
Author(s):  
Jag Mohan
Keyword(s):  
Drosophila Melanogaster ◽  
Ribosomal Rna ◽  
In Vivo Studies ◽  
28S Rrna ◽  
5S Rna ◽  
Rna Molecules ◽  
Molar Ratios ◽  
Rna Genes

ABSTRACT Ribosomes contain one molecule each of 5S, 18S and 28S RNA. In Drosophila melanogaster although the genes for 18S+28S are physically separated from the 5S RNA genes, the multiplicity of various ribosomal RNA genes is roughly the same. Thus a coordinate synthesis of these three molecules might seem feasible. This problem has been approached by determining the molar ratios of various RNA's in ovaries and in adult flies. In ovaries there is a slight excess of 5S RNA molecules over other rRNA's, but in adult flies no such differences exist. Bobbed mutants also have the same molar ratios as wild-type flies. Results on 5S RNA synthesis in both in vitro and in vivo studies show that it is reduced in coordination with 18S+28S rRNA in the bobbed mutants of Drosophila melanogaster. Various possibilities are discussed in considering the implications of these results.

Formation and Structure of Casein Micelles in Lactating Mammary Tissue

1970 ◽  
Vol 28 ◽  
pp. 150-151
Author(s):  
Robert J. Carroll ◽  
Marvin P. Thompson ◽  
Harold M. Farrell
Keyword(s):  
Size Distribution ◽  
G Protein ◽  
Milk Proteins ◽  
Mammary Tissue ◽  
Colloidal System ◽  
Casein Micelles ◽  
The Stability

Milk is an unusually stable colloidal system; the stability of this system is due primarily to the formation of micelles by the major milk proteins, the caseins. Numerous models for the structure of casein micelles have been proposed; these models have been formulated on the basis of in vitro studies. Synthetic casein micelles (i.e., those formed by mixing the purified αsl- and k-caseins with Ca2+ in appropriate ratios) are dissimilar to those from freshly-drawn milks in (i) size distribution, (ii) ratio of Ca/P, and (iii) solvation (g. water/g. protein). Evidently, in vivo organization of the caseins into the micellar form occurs in-a manner which is not identical to the in vitro mode of formation.

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