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1.
Br J Haematol ; 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38532575

ABSTRACT

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of haematological cancers with generally poor clinical outcomes. However, a subset of patients experience durable disease control, and little is known regarding long-term outcomes. The International T-cell Lymphoma Project (ITCLP) is the largest prospectively collected cohort of patients with PTCLs, providing insight into clinical outcomes at academic medical centres globally. We performed a long-term outcome analysis on patients from the ITCLP with available 10-year follow-up data (n = 735). The overall response rate to first-line therapy was 68%, while 5- and 10-year overall survival estimates were 49% and 40% respectively. Most deaths occurred prior to 5 years, and for patients alive at 5 years, the chance of surviving to 10 years was 84%. However, lymphoma remained the leading cause of death in the 5- to 10-year period (67%). Low-risk International Prognostic Index and Prognostic Index for T-cell lymphoma scores both identified patients with improved survival, while in multivariate analysis, age >60 years and Eastern Cooperative Oncology Group performance status 2-4 were associated with inferior outcomes. The favourable survival seen in patients achieving durable initial disease control emphasizes the unmet need for optimal front-line therapeutic approaches in PTCLs.

4.
Vopr Virusol ; 56(2): 28-32, 2011.
Article in Russian | MEDLINE | ID: mdl-21545038

ABSTRACT

Institute of Medical Primatology, Russian Academy of Medical Sciences, Sochi The conserved regions of nucleotide sequences were found in primate cytomegaloviruses (CMV). Universal primers were designed for the consensus sequence of a conservative region of the UL56 gene of the betaherpesvirinae subfamily. Amplification, sequencing, and phylogenetic analysis of the fragments of CMV strains isolated from man and different primate species were made. Analysis of sequenced gene fragments showed that the UL56 gene area is most suitable for the phylogenetic analysis of primate CMV and could identify several groups of clusters by the degree of relationship among the viruses of this family.


Subject(s)
Consensus Sequence/genetics , Cytomegalovirus/genetics , DNA Primers/genetics , DNA, Viral/genetics , Phylogeny , Animals , Base Sequence , Cercopithecinae , Cytomegalovirus/isolation & purification , Humans , Molecular Sequence Data , Polymerase Chain Reaction , Salivary Glands/chemistry , Sequence Alignment , Software , Viral Structural Proteins/blood
5.
Trends Biochem Sci ; 15(4): 158-62, 1990 Apr.
Article in English | MEDLINE | ID: mdl-2160143

ABSTRACT

Crystallographic studies of enzymes complexed with suitable ligands are an important tool to aid our understanding of biological catalysis. To this goal, a contribution is made by analysing structures of complexes formed by three guanyl-specific ribonucleases with guanosine 3'-monophosphate.


Subject(s)
Guanine Nucleotides/metabolism , Guanosine Monophosphate/metabolism , Ribonucleases/metabolism , Amino Acid Sequence , Bacteria/enzymology , Binding Sites , Fungi/enzymology , Models, Molecular , Molecular Sequence Data , Sequence Homology, Nucleic Acid , Substrate Specificity
6.
Structure ; 4(4): 375-86, 1996 Apr 15.
Article in English | MEDLINE | ID: mdl-8740360

ABSTRACT

BACKGROUND: Stromelysin belongs to a family of zinc-dependent endopeptidases referred to as matrix metalloproteinases (MMPs, matrixins) because of their capacity for selective degradation of various components of the extracellular matrix. Matrixins play key roles in diseases as diverse as arthritis and cancer and hence are important targets for therapeutic intervention. RESULTS: The crystal structure of the stromelysin catalytic domain (SCD) with bound hydroxamate inhibitor, solved by multiple isomorphous replacement, shows deep S1' specificity pocket which explains differences in inhibitors binding between the collagenases and stromelysin. The binding of calcium ions by loops at the two ends of a beta-strand which marks the boundary of the active site provides a structural rationale for the importance of these cations for stability and catalytic activity. Major differences between the matrixins are clustered in two regions forming the entrance to the active site and hence may be determinants of substrate selectivity. CONCLUSIONS: Structural comparisons of SCD with representative members of the metalloproteinase superfamily clearly highlight the conservation of key secondary structural elements, in spite of major variations in the sequences including insertions and deletions of functional domains. However, the three-dimensional structure of SCD, which is generally closely related to the collagenases, shows significant differences not only in the peripheral regions but also in the specificity pockets; these latter differences should facilitate the rational design of specific inhibitors.


Subject(s)
Enzyme Inhibitors/chemistry , Matrix Metalloproteinase 3/chemistry , Matrix Metalloproteinase Inhibitors , Amino Acid Sequence , Binding Sites , Collagenases/chemistry , Crystallography, X-Ray , Enzyme Inhibitors/metabolism , Hydroxamic Acids/chemistry , Magnetic Resonance Spectroscopy , Matrix Metalloproteinase 3/metabolism , Metalloendopeptidases/chemistry , Models, Molecular , Molecular Sequence Data , Protein Conformation , Sequence Homology, Amino Acid , Zinc/chemistry , Zinc/metabolism
7.
Protein Sci ; 2(9): 1373-82, 1993 Sep.
Article in English | MEDLINE | ID: mdl-8401223

ABSTRACT

Crystal and NMR structures of helical cytokines--interleukin-4 (IL-4), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-2 (IL-2)--have been compared. Root mean square deviations in the C alpha coordinates for the conserved regions of the helices were 1-2 A between different cytokines, about twice the differences observed for independently determined crystal and solution structures of IL-4. Considerable similarity in amino acid sequence in the areas expected to interact with the receptors was detected, and the available mutagenesis data for these cytokines were correlated with structure conservation. Models of cytokine-receptor interactions were postulated for IL-4 based on its structure as well as on the published structure of human growth hormone interacting with its receptors (de Vos, A.M., Ultsch, M., & Kossiakoff, A.A., 1992, Science 255, 306-312). Patches of positively charged residues on the surfaces of helices C and D of IL-4 may be responsible for the interactions with the negatively charged residues found in the complementary parts of the IL-4 receptors.


Subject(s)
Cytokines/chemistry , Hematopoiesis , Receptors, Cytokine/metabolism , Amino Acid Sequence , Crystallization , Crystallography, X-Ray , Cytokines/metabolism , Granulocyte-Macrophage Colony-Stimulating Factor/chemistry , Humans , Interleukin-2/chemistry , Interleukin-4/chemistry , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Sequence Data , Molecular Structure
8.
Protein Sci ; 8(7): 1455-62, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10422833

ABSTRACT

Effective inhibitors of matrix metalloproteinases (MMPs), a family of connective tissue-degrading enzymes, could be useful for the treatment of diseases such as cancer, multiple sclerosis, and arthritis. Many of the known MMP inhibitors are derived from peptide substrates, with high potency in vitro but little selectivity among MMPs and poor bioavailability. We have discovered nonpeptidic MMP inhibitors with improved properties, and report here the crystal structures of human stromelysin-1 catalytic domain (SCD) complexed with four of these inhibitors. The structures were determined and refined at resolutions ranging from 1.64 to 2.0 A. Each inhibitor binds in the active site of SCD such that a bulky diphenyl piperidine moiety penetrates a deep, predominantly hydrophobic S'1 pocket. The active site structure of the SCD is similar in all four inhibitor complexes, but differs substantially from the peptide hydroxamate complex, which has a smaller side chain bound in the S'1 pocket. The largest differences occur in the loop forming the "top" of this pocket. The occupation of these nonpeptidic inhibitors in the S'1 pocket provides a structural basis to explain their selectivity among MMPs. An analysis of the unique binding mode predicts structural modifications to design improved MMP inhibitors.


Subject(s)
Matrix Metalloproteinase 3/chemistry , Protease Inhibitors/chemistry , Binding Sites , Catalytic Domain , Crystallography, X-Ray , Humans , Matrix Metalloproteinase 3/metabolism , Matrix Metalloproteinase Inhibitors , Models, Molecular , Protease Inhibitors/metabolism , Protein Binding
9.
FEBS Lett ; 309(1): 59-64, 1992 Aug 31.
Article in English | MEDLINE | ID: mdl-1511746

ABSTRACT

The crystal structure of human recombinant interleukin-4 (IL-4) has been solved by multiple isomorphous replacement, and refined to an R factor of 0.218 at 2.25 A resolution. The molecule is a left-handed four-helix bundle with a short stretch of beta sheet. The structure bears close resemblance to other cytokines such as granulocyte-macrophage colony stimulating factor (GM-CSF). Although no sequence similarity of IL-4 to GM-CSF and other related cytokines has been previously postulated, structure-based alignment of IL-4 and GM-CSF revealed that the core of the molecules, including large parts of all four helices and extending over half of the molecule, has 30% sequence identity. This may have identified regions which are not only important to maintain structure, but could also play a role in receptor binding.


Subject(s)
Interleukin-4/chemistry , Amino Acid Sequence , Granulocyte-Macrophage Colony-Stimulating Factor/chemistry , Humans , Protein Conformation , Recombinant Proteins/chemistry , Software , X-Ray Diffraction/methods
10.
J Med Chem ; 43(2): 156-66, 2000 Jan 27.
Article in English | MEDLINE | ID: mdl-10649971

ABSTRACT

A series of biphenylsulfonamide derivatives of (S)-2-(biphenyl-4-sulfonylamino)-3-methylbutyric acid (5) were prepared and evaluated for their ability to inhibit matrix metalloproteinases (MMPs). For this series of compounds, our objective was to systematically replace substituents appended to the biphenyl and alpha-position of 5 with structurally diverse functionalities to assess the effects these changes have on biological and pharmacokinetic activity. The ensuing structure-activity relationship (SAR) studies showed that biphenylsulfonamides substituted with bromine in the 4'-position (11c) significantly improved in vitro activity and exhibited superior pharmacokinetics (C(max), t(1/2), AUCs), relative to compound 5. Varying the lipophilicity of the alpha-position by replacing the isopropyl group of 11c with a variety of substituents, in general, maintained potency versus MMP-2, -3, and -13 but decreased the oral systemic availability. Subsequent evaluation of its enantiomer, 11c', showed that both compounds were equally effective MMP inhibitors. In contrast, the corresponding hydroxamic acid enantiomeric pair, 16a (S-isomer) and 16a' (R-isomer), stereoselectivity inhibited MMPs. For the first time in this series, 16a' provided nanomolar potency against MMP-1, -7, and -9 (IC(50)'s = 110, 140, and 18 nM, respectively), whereas 16a was less potent against these MMPs (IC(50)'s = 24, 78, and 84 microM, respectively). However, unlike 11c, compound 16a' afforded very low plasma concentrations following a single 5 mg/kg oral dose in rat. Subsequent X-ray crystal structures of the catalytic domain of stromelysin (MMP-3CD) complexed with inhibitors from closely related series established the differences in the binding mode of carboxylic acid-based inhibitors (11c,c') relative to the corresponding hydroxamic acids (16a,a').


Subject(s)
Matrix Metalloproteinase Inhibitors , Protease Inhibitors/chemistry , Protease Inhibitors/pharmacology , Sulfonamides/chemistry , Sulfonamides/pharmacology , Animals , Area Under Curve , Biological Availability , Crystallography, X-Ray , Humans , Magnetic Resonance Spectroscopy , Models, Molecular , Protease Inhibitors/pharmacokinetics , Rats , Structure-Activity Relationship , Sulfonamides/pharmacokinetics
11.
J Med Chem ; 44(14): 2319-32, 2001 Jul 05.
Article in English | MEDLINE | ID: mdl-11428926

ABSTRACT

Due largely to the emergence of multi-drug-resistant HIV strains, the development of new HIV protease inhibitors remains a high priority for the pharmaceutical industry. Toward this end, we previously identified a 4-hydroxy-5,6-dihydropyrone lead compound (CI-1029, 1) which possesses excellent activity against the protease enzyme, good antiviral efficacy in cellular assays, and promising bioavailability in several animal species. The search for a suitable back-up candidate centered on the replacement of the aniline moiety at C-6 with an appropriately substituted heterocyle. In general, this series of heterocyclic inhibitors displayed good activity (in both enzymatic and cellular tests) and low cellular toxicity; furthermore, several analogues exhibited improved pharmacokinetic parameters in animal models. The compound with the best combination of high potency, low toxicity, and favorable bioavailabilty was (S)-3-(2-tert-butyl-4-hydroxymethyl-5-methyl-phenylsulfanyl)-4-hydroxy-6-isopropyl-6-(2-thiophen-3-yl-ethyl)-5,6-dihydro-pyran-2-one (13-(S)). This thiophene derivative also exhibited excellent antiviral efficacy against mutant HIV protease and resistant HIV strains. For these reasons, compound 13-(S) was chosen for further preclinical evaluation.


Subject(s)
HIV Protease Inhibitors/chemical synthesis , Pyrones/chemical synthesis , Sulfides/chemical synthesis , Animals , Biological Availability , Cell Line , Chromatography, High Pressure Liquid , Dogs , Drug Evaluation, Preclinical , Drug Resistance, Microbial , HIV/drug effects , HIV Protease/chemistry , HIV Protease/genetics , HIV Protease Inhibitors/chemistry , HIV Protease Inhibitors/pharmacokinetics , HIV Protease Inhibitors/pharmacology , HIV-1/enzymology , Humans , Lymphocytes/virology , Mice , Mutation , Pyrones/chemistry , Pyrones/pharmacokinetics , Pyrones/pharmacology , Rats , Stereoisomerism , Structure-Activity Relationship , Sulfides/chemistry , Sulfides/pharmacokinetics , Sulfides/pharmacology
12.
J Med Chem ; 40(23): 3781-92, 1997 Nov 07.
Article in English | MEDLINE | ID: mdl-9371244

ABSTRACT

The 4-hydroxy-5,6-dihydropyrone template was utilized as a flexible scaffolding from which to build potent active site inhibitors of HIV protease. Dihydropyrone 1c (5,6-dihydro-4-hydroxy-6-phenyl-3-[(2-phenylethyl)thio]-2H-pyran-2-one) was modeled in the active site of HIV protease utilizing a similar binding mode found for the previously reported 4-hydroxybenzopyran-2-ones. Our model led us to pursue the synthesis of 6,6-disubstituted dihydropyrones with the aim of filling S1 and S2 and thereby increasing the potency of the parent dihydropyrone 1c which did not fill S2. Toward this end we attached various hydrophobic and hydrophilic side chains at the 6-position of the dihydropyrone to mimic the natural and unnatural amino acids known to be effective substrates at P2 and P2'. Parent dihydropyrone 1c (IC50 = 2100 nM) was elaborated into compounds with greater than a 100-fold increase in potency [18c, IC50 = 5 nM, 5-(3,6-dihydro-4-hydroxy-6-oxo-2-phenyl-5-[2-phenylethyl)thio] -2H-pyran-2-yl)pentanoic acid and 12c, IC50 = 51 nM, 5,6-dihydro-4-hydroxy-6-phenyl-6-(2-phenylethyl)-3- [(2-phenyl-ethyl)thio]-2H-pyran-2-one]. Optimization of the 3-position fragment to fill S1' and S2' afforded potent HIV protease inhibitor 49 [IC50 = 10 nM, 3-[(2-tert-butyl-5-methylphenyl)sulfanyl]-5,6-dihydro-4 -hydroxy-6-phenyl-6-(2-phenylethyl)-2H-pyran-2-one]. The resulting low molecular weight compounds (< 475) have one or no chiral centers and are readily synthesized.


Subject(s)
HIV Protease Inhibitors/chemical synthesis , HIV Protease Inhibitors/pharmacology , Pyrones/chemical synthesis , Pyrones/pharmacology , Anti-HIV Agents/chemical synthesis , Anti-HIV Agents/pharmacology , Binding Sites , Coumarins/chemical synthesis , Coumarins/pharmacology , Crystallography, X-Ray , Drug Design , HIV Protease/metabolism , HIV-1/enzymology , Stereoisomerism , Structure-Activity Relationship
13.
Cancer Genet Cytogenet ; 11(1): 53-60, 1984 Jan.
Article in English | MEDLINE | ID: mdl-6690023

ABSTRACT

A case of nodular malignant melanoma (level V of Clark's classification) with homogeneously staining regions (HSR) on the long arm of one chromosome #2 is described. Ultrastructural observation of melanosomic and promelanosomic granules near Golgi's vesicles confirmed the histologic diagnosis. Chromosome analysis was performed on nine metaphases from a bone marrow sample and 76 metaphases from culture of the malignant skin tumor. G-banding revealed the presence of a clone with trisomy #8 and another cell line with the HSR marker. This is the first report of HSR in human melanoma cells. As HSR has been found only in malignant cells, we believe that among the many factors that influence the patients' clinical evolution and poor response to treatment, the genic imbalance is of the utmost importance.


Subject(s)
Chromosome Aberrations , Chromosome Disorders , Melanoma/genetics , Aged , Chromosomes, Human, 1-3/ultrastructure , Chromosomes, Human, 6-12 and X , Humans , Karyotyping , Male , Melanoma/pathology , Skin Neoplasms/genetics , Skin Neoplasms/pathology , Trisomy
14.
J Biomol Struct Dyn ; 4(5): 885-93, 1987 Apr.
Article in English | MEDLINE | ID: mdl-3270531

ABSTRACT

A correlation between the distribution of charged side groups in the globule of Bacillus intermedius 7P ribonuclease (binase) and the process of heat denaturation was studied at different pH values in order to estimate a relation between charge distribution in globular proteins and the character of cooperative thermodynamic transitions. As was shown by comparing the results of scanning microcalorimetric analysis of heat denaturation with the three-dimensional structure of binase, at optimal pH the molecule exists as a single cooperative system stabilized by hydrogen bonds, Van der Waals' contacts, and electrostatic interactions like salt bridges. At pH lower than 4.0 (below the physiological optimum) the cooperativity type of the system was found to change due to a reversible cooperative transition in the ternary structure of the protein globule. It has been concluded that the molecular architecture and the arrangement of atoms do not change considerably in different environments; thus the thermodynamic properties of the globule vary due to the alteration of charge distribution and the consequent changes in the size and number of cooperative regions of the globule. Thus, structural and energetic domains may be non-coincident in proteins.


Subject(s)
Bacillus/enzymology , Bacterial Proteins , Endoribonucleases , Calorimetry, Differential Scanning , Hydrogen Bonding , Hydrogen-Ion Concentration , Models, Molecular , Protein Conformation , Protein Denaturation , Spectrometry, Fluorescence , Thermodynamics
15.
IEEE Trans Biomed Eng ; 46(8): 937-46, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10431458

ABSTRACT

A method of image reconstruction in three-dimensional (3-D) microwave tomography in a weak dielectric contrast case has been developed. By utilizing only one component of the vector electromagnetic field this method allows successful reconstruction of images of 3-D mathematical phantoms. A prototype of the 3-D microwave tomographic system capable of imaging 3-D objects has been constructed. The system operates at a frequency of 2.36 GHz and utilizes a code-division technique. With dimensions of the cylindrical working chamber z = 40 cm and d = 60 cm, the system allows measurement of an attenuation up to 120 dB having signal-to-noise ratio about 30 dB. The direct problem solutions for different mathematical approaches were compared with an experimentally measured field distribution inside the working chamber. The tomographic system and the reconstruction method were tested in simple experimental imaging.


Subject(s)
Image Processing, Computer-Assisted/methods , Microwaves , Models, Cardiovascular , Tomography/methods , Electromagnetic Fields , Equipment Design , Humans , Nonlinear Dynamics , Phantoms, Imaging , Tomography/instrumentation , Vectorcardiography/methods
16.
Neuroscience ; 246: 160-9, 2013 Aug 29.
Article in English | MEDLINE | ID: mdl-23644055

ABSTRACT

Our prior research has shown that the transcription of endoplasmic reticulum (ER) stress transcription factors activating transcription factor 3 (ATF3) and ATF4 are induced by amphetamine and restraint stress in rat striatum. However, presently the full extent of ER stress responses to psychological stress or cocaine, and which of the three ER stress pathways is activated is unknown. The current study examines transcriptional responses of key ER stress target genes subsequent to psychological stress or cocaine. Rats were subjected to acute or repeated restraint stress or cocaine treatment and mRNA was isolated from dorsal striatum, medial prefrontal cortex and nucleus accumbens brain tissue. ER stress gene mRNA expression was measured using quantitative polymerase chain reaction (PCR) and RNA sequencing. Restraint stress and cocaine-induced transcription of the classic ER stress-induced genes (BIP, CHOP, ATF3 and GADD34) and of two other ER stress components x-box binding protein 1 (XBP1) and ATF6. In addition, rats living in an enriched environment (large group cage with novel toys changed daily) exhibited rapid induction of GADD34 and ATF3 after 30 min of exploring novel toys, suggesting these genes are also involved in normal non-pathological signaling. However, environmental enrichment, a paradigm that produces protective addiction and depression phenotypes in rats, attenuated the rapid induction of ATF3 and GADD34 after restraint stress. These experiments provide a sensitive measure of ER stress and, more importantly, these results offer good evidence of the activation of ER stress mechanisms from psychological stress, cocaine and natural reward. Thus, ER stress genes may be targets for novel therapeutic targets for depression and addiction.


Subject(s)
Brain/metabolism , Cocaine/administration & dosage , Endoplasmic Reticulum Stress/physiology , Gene Expression Regulation , Reward , Stress, Psychological/metabolism , Activating Transcription Factor 3/biosynthesis , Animals , Antigens, Differentiation/biosynthesis , Brain/drug effects , Endoplasmic Reticulum Stress/drug effects , Male , Proto-Oncogene Proteins/biosynthesis , Rats , Rats, Sprague-Dawley , Self Administration , Stress, Psychological/psychology
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