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Hartenstein K, Sinha P, Mishra A, Schenkel H, Török I, Mechler BM. The congested-like tracheae gene of Drosophila melanogaster encodes a member of the mitochondrial carrier family required for gas-filling of the tracheal system and expansion of the wings after eclosion. Genetics 1997; 147:1755-68. [PMID: 9409834 PMCID: PMC1208344 DOI: 10.1093/genetics/147.4.1755] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
A recessive semi-lethal mutation resulting from the insertion of a P-lacW transposon at the cytological position 23A on the polytene chromosomes of Drosophila melanogaster was found to affect the unfolding and expansion of the wings resulting in a loss of venation and a marked decrease in their size. Lethality was polyphasic with numerous animals dying during early larval development and displaying apparently collapsed tracheal trees. The gene was therefore designated as congested-like tracheae, or colt. The colt mutation resulted from the insertion of a P-lacW transposon within the coding region of a 1.4-kb transcript. Wild-type function was restored by inducing a precise excision of the P-lacW transposon, while a deletion of the colt locus, produced by imprecise excision of the P element, showed a phenotype similar to that of the original P insert. The colt gene consists of a single exon and encodes a protein of 306 amino acids made of three tandem repeats, each characterized by two predicted transmembrane segments and a loop domain. The COLT protein shares extensive homology with proteins in the mitochondrial carrier family and particularly with the DIF-1 protein of Caenorhabditis elegans, which has been shown to be maternally required for embryonic tissue differentiation. Our analysis revealed that zygotic colt function is dispensable for normal embryonic morphogenesis but is required for gas-filling of the tracheal system at hatching time of the embryo and for normal epithelial morphogenesis of the wings.
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Iliopoulos I, Török I, Mechler BM. The DnaJ60 gene of Drosophila melanogaster encodes a new member of the DnaJ family of proteins. Biol Chem 1997; 378:1177-81. [PMID: 9372188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In eukaryotes the DnaJ homolog constitute a family of proteins with diverse functions which all appear to involve the chaperone activity of Hsp70. Here, we report the molecular characterization of DnaJ60, a gene located at 60C on the right arm of the second chromosome of Drosophila melanogaster and encoding a putative protein of 217 amino acids with a molecular mass of 27.7-kDa and a pl of 10.5. The N-terminal region of the DnaJ60 protein displays a significant sequence similarity with the J domain of DnaJ proteins and contains a centrally located hydrophobic segment suggesting the occurrence of a membrane spanning domain. Northern blot analysis detected a 0.75-kb transcript which is weakly expressed in embryos, larvae and females but intensively expressed in adult males. In situ localization revealed that the DnaJ60 transcript is highly expressed in male testes and the ejaculary bulb but at an undetectable level in ovaries suggesting that the DnaJ60 protein may play an important function during spermatogenesis and/or in the male genital tract.
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Török I, Paál T. [Chromatographic determination of novamidazofen in pharmaceutical preparations]. ACTA PHARMACEUTICA HUNGARICA 1997; 67:193-9. [PMID: 9432866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Novamidazofen (metamizol) has been used again as antipyretic and antirheumatic also in abroad recently. In aqueous solutions, such as injections, hydrolysis takes place in its formaldehyde sulfoxylate side chain resulting in an equilibrium mixture of novamidazofen and nor-amidazofen. A high-performance liquid chromatographic method was developed to study the hydrolysis and for the selective and accurate determination of the two components. UV detection at 242 nm wavelength, where the absorbance of novamidazofen and nor-amidazofen were identical, was applied. The rate constants k1 and k3 of the opposite direction reactions as well as K = k1 k3(-1), the hydrolytic equilibrium constant were determined. In aqueous solution, at I-->0 ionic strength and 25 degrees C pK = 3.52 +/- 0.12; 10(4) k1 = 1.74 (+/- 0.25) min-1, P = 0.95. Addition of methanol to the system decreased both the rate and equilibrium constants of the hydrolysis. For the quantitation of novamidazofen Nucleosil C18 column and 20 mmol dm-3 natrium sulphate in methanol-water 40 + 60 V + V eluent were used. The calibration curve was linear in the 20 to 1000 ng range. This method is suitable also for the detection of other, mostly oxidised impurities. A thin-layer chromatographic procedure was also developed on silica GF254 applying acetone-water-ether 30 + 40 + 5 V + V + V eluent. After extraction with chloroform, the oxidised decomposition products can be detected also in injections allowed to stand for a few minutes in an open vessel. The densitometric version of the TLC method was also developed but its precision was lower than that of the HPLC.
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Izer K, Török I, Magyarné Pintér G, Varsányi LE, Lipták J. [Stability of rifampicin in eyedrops]. ACTA PHARMACEUTICA HUNGARICA 1996; 66:157-163. [PMID: 9082836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The best composition of rifampicin eye-drops for extemporaneous preparation in pharmacies was developed by the authors. The stability of the eye-drops has been studied and storage condition and shelf-life were determined. The preparation, may be stored at minus 12 degrees C for one month and may be subsequently used when stored between 2 and 8 degrees C after the first opening for five days. Rifampicin and its degradation products have been separated by TLC using silicagel layer and chloroform-methanol (42 : 58) eluent. After separation of rifampicin and its degradation products their quantity have been determined by densitometry at 475 wavelength (540 nm for rifampicin quinone). This rifampicin eye-drops have been recommended for inclusion into the 7th Edition of the Official Model Prescriptions (Formulae Normales).
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Kovács I, Török I, Zombori J, Kása P. Neuropathologic changes in the olfactory bulb in Alzheimer's disease. NEUROBIOLOGY (BUDAPEST, HUNGARY) 1996; 4:123-6. [PMID: 9116690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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31
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Török L, Simon G, Csornai A, Tápai M, Török I. Scedosporium apiospermum infection imitating lymphocutaneous sporotrichosis in a patient with myeloblastic-monocytic leukaemia. Br J Dermatol 1995; 133:805-9. [PMID: 8555041 DOI: 10.1111/j.1365-2133.1995.tb02763.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A 63-year-old man with a history of myeloblastic-monocytic leukaemia developed partly suppurating cutaneous nodules on the lower left leg. The nodules proceeded to spread in a linear fashion up the limb, following the line of the lymphatic drainage. Mycological examination of a skin biopsy demonstrated Scedoporium apiospermum. This case highlights the potential for Scedosporium species to act as opportunistic infections in immunosuppressed humans.
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Török I, Strand D, Schmitt R, Tick G, Török T, Kiss I, Mechler BM. The overgrown hematopoietic organs-31 tumor suppressor gene of Drosophila encodes an Importin-like protein accumulating in the nucleus at the onset of mitosis. J Biophys Biochem Cytol 1995; 129:1473-89. [PMID: 7790349 PMCID: PMC2291178 DOI: 10.1083/jcb.129.6.1473] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The tumor suppressor gene overgrown hematopoietic organs-31 (oho31) of Drosophila encodes a protein with extensive homology to the Importin protein of Xenopus (50% identity), the related yeast SRP1 protein, and the mammalian hSRP1 and RCH1 proteins. A strong reduction in the expression of oho31 by a P element inserted in the 5' untranslated region of the oho31 transcript or a complete inactivation of oho31 by imprecise P element excision leads to malignant development of the hematopoietic organs and the genital disc, as shown by their growth autonomy in transplantation assays. We have cloned the oho31 gene of Drosophila melanogaster and determined its nucleotide sequence. The gene encodes a phosphoprotein of 522 amino acids made of three domains: a central hydrophobic domain of eight repeats of 42-44 amino acids each, displaying similarity to the arm motif found in junctional and nucleopore complex proteins, and flanked by two hydrophilic NH2- and COOH-terminal domains. Immunostaining revealed that the OHO31 protein is supplied maternally and rapidly degraded during the first 13 nuclear divisions. Thereafter, the OHO31 protein is predominantly expressed, albeit at reduced levels, in proliferating tissues. During the interphase of early embryonic cell cycles, the OHO31 protein is present in the cytoplasm and massively accumulates in the nucleus at the onset of mitosis in late interphase and prophase. The nuclear import of OHO31 is, however, less pronounced during later developmental stages. These results suggest that, similar to Importin, OHO31 may act as a cytosolic factor in nuclear transport. Moreover, the cell cycle-dependent accumulation of OHO31 in the nucleus indicates that this protein may be required for critical nuclear reactions occurring at the onset of mitosis.
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Raska I, Dundr M, Koberna K, Melcák I, Risueño MC, Török I. Does the synthesis of ribosomal RNA take place within nucleolar fibrillar centers or dense fibrillar components? A critical appraisal. J Struct Biol 1995; 114:1-22. [PMID: 7772414 DOI: 10.1006/jsbi.1995.1001] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The localization of transcribing rRNA genes within nucleoli of mammalian cells, although intensively studied, has not been established. Most published papers on this topic situate transcribing ribosomal genes either to nucleolar fibrillar centers or to nucleolar dense fibrillar components. To clarify this point, we have generated the electron microscopic affinity cytochemistry picture of the nucleolus of cultured mammalian cells. Three kinds of affinity probes have been used: (1) probes to nucleolar chromatin, including rDNA sequences; (2) probes to a number of macromolecules (such as RNA polymerase I) which are directly, or indirectly, involved in the synthesis and processing of rRNA and formation of preribosomes; (3) antibodies to bromouridine for a recently standardized nonisotopical method depicting incorporated bromouridine within RNA. The results suggest the localization of transcription sites not only to dense fibrillar components but also to the border region between these components and fibrillar centers. Our data support a hypothesis that in metabolically active mammalian nucleoli, fibrillar centers and dense fibrillar components form a single functional domain for the transcription of rRNA genes, with nascent transcripts generating "automatically" dense fibrillar components. Through the active process of transcription, individual rRNA genes thus become engulfed within dense fibrillar components.
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Török L, Simon G, Csornai A, Tápai M, Török I. [Scedosporium apiospermum infection in a patient with myelomonocytic leukemia presenting as lympho-cutaneous sporotrichosis]. Orv Hetil 1994; 135:2377-80. [PMID: 7970657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
63 year old patient is presented with myelo-monocytic leukemia, in whom subcutaneous nodules developed at the lower limb, spreading along the lymph vessels, and partly ulcerating. By mycologic investigation Scedosporium apiospermum was disclosed. Attention is drawn to human infections brought about by opportunistic Scedosporium species.
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Izer K, Török I, Pintér-Magyar G. Stability of oxytetracycline hydrochloride in eye-drops, prepared in pharmacies. ACTA PHARMACEUTICA HUNGARICA 1994; 64:63-6. [PMID: 8017210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In the ophthalmological practice the so-called "Oxytetracycline-eye-drop" is frequently used, prepared in pharmacies ex tempore with a short self-life (3 days). In this paper a TLC-densitometric method is described for the determination of the degradation products of oxytetracycline HCl (OTC) formed in the "Oxytetracycline-eye-drop". A chloroform-methanol-water (65 + 25 + 5 v/v) solvent system is applied on silica gel TLC plate, predeveloped with saturated disodium ethylenediamine-tetraacetate aqueous solution. UV densitometry at 254 nm is used for quantitative determination. The chemical stability of OTC in different eye-drops as well as the effects of the pH and the mode of the preparation and storage conditions on the decomposition process are discussed.
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Baksa K, Morawietz H, Dombrádi V, Axton M, Taubert H, Szabó G, Török I, Udvardy A, Gyurkovics H, Szöör B. Mutations in the protein phosphatase 1 gene at 87B can differentially affect suppression of position-effect variegation and mitosis in Drosophila melanogaster. Genetics 1993; 135:117-25. [PMID: 8224813 PMCID: PMC1205611 DOI: 10.1093/genetics/135.1.117] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The suppressor of position effect variegation (PEV) locus Su-var(3)6 maps to 87B5-10. The breakpoints of deficiencies that define this interval have been placed on a 250-kb molecular map of the region. The locus is allelic to the ck19 complementation group previously shown to encode a type 1 serine-threonine protein phosphatase (PP1) catalytic subunit. When introduced into flies by P element-mediated transformation, a 5.8-kb genomic fragment carrying this gene overcomes the suppressor phenotype of Su-var(3)6(01) and recessive lethality of all mutations of the locus. Four of the mutant alleles at the locus show a broad correlation between high levels of suppression of PEV, a high frequency of aberrant mitosis and low PP1 activity in larval extracts. However, some alleles with low PP1 activity show weak suppression of PEV with a high frequency of abnormal mitosis, whereas others show strong suppression of PEV with normal mitosis. The basis for these discussed.
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Török I, Hartenstein K, Kalmes A, Schmitt R, Strand D, Mechler BM. The l(2)gl homologue of Drosophila pseudoobscura suppresses tumorigenicity in transgenic Drosophila melanogaster. Oncogene 1993; 8:1537-49. [PMID: 8389031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Mutations in the tumour-suppressor gene lethal(2)giant larvae (l(2)gl) of Drosophila cause malignant transformation of the optic centres of the larval brain and the imaginal discs. We report the cloning and sequencing of the l(2)gl gene from Drosophila pseudoobscura. Comparison of this sequence with D. melanogaster reveals a significant sequence conservation within the l(2)gl protein-coding domain and a strong sequence divergence in the 5' promoter region and in the introns. The deduced amino acid sequence of the D. pseudoobscura l(2)gl protein shows 17.7% divergence from D. melanogaster. However, despite these evolutionary differences, the D. pseudoobscura l(2)gl gene can fully suppress tumorigenicity and restore a normal development in l(2)gl-deficient D. melanogaster flies, although the rescued animals display poor viability and fertility. Furthermore, in D. melanogaster transgenic flies, the D. pseudoobscura l(2)gl protein is produced at a similar level as the D. melanogaster l(2)gl protein and displays an identical spatial pattern of expression. This shows that the highly divergent cis-regulatory elements of the D. pseudoobscura transgene can be fully recognized in D. melanogaster and lead to the synthesis of a transgenic protein that has enough specificity conserved for replacing the tumour-suppressor function normally fulfilled by the D. melanogaster l(2)gl protein.
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Németh G, Török I, Paál T. [Degradation of succinylcholine chloride]. ACTA PHARMACEUTICA HUNGARICA 1993; 63:151-6. [PMID: 8362654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Quantitative thin-layer chormatographic method has been developed for the investigation of the degradation of injection formulations containing succinylcholinium chloride. The method is based on the denistometric determination of the main degradation product, choline at 430 nm after visualization with iodine vapour. The stability of the injection was investigated under various storage conditions and it has been stated that considerable decomposition takes place during as short a period as one week.
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Vogt F, Csoma E, Timmer M, Esztó K, Hollósy A, Schleer M, Török I. [Lyme borreliosis]. Orv Hetil 1993; 134:271-3. [PMID: 8426733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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40
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Hernádi Z, Lampé L, Török I, Birinyi L. [Importance of prognostic factors in the prognosis of cancer of the endometrium]. Orv Hetil 1992; 133:3069-73. [PMID: 1448272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
126 stage I and II endometrial cancer patients were followed up for at least 5 years to evaluate the impact of surgical-pathological risk factors on the survival. Out of the prognostic variables evaluated the age and clinical stage failed to influence the 5-year survival rate. The effect on survival of factors such as low grade of differentiation and the depth of myometrial infiltration was however significant, (p < 0.01 and p < 0.001 respectively). The early local recurrence has also significant negative prognostic value (p < 0.05). This latter can be effectively prevented through the prehysterectomy suture of the external cervical os. On the basis of their findings authors suggest to consider the grade and the depth of myometrial invasion beside the clinical stage at the determination of the extension of the surgical procedure and at the decision on the administration of postoperative irradiation.
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Török I, László A, Zombori J. [Giant pigmented nevus associated with leptomeningeal melanocytosis]. Orv Hetil 1992; 133:1565-8. [PMID: 1408056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A case of a thirteen-year old boy is reported with congenital pigmented nevi on the large part of the trunk and on the extremities. From his age of six generalised epileptiform convulsions were present. Owing to the suspicion of intracranial process he was examined with a negative result. He died of brain edema. On section cerebrospinal leptomeningeal melanocytosis was found beside the nevi. In addition to the clinical findings and treatment the morphological lesions are detailed too at macroscopic, microscopic and ultrastructural level discussing the possibility of the malignisation.
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Zombori J, László A, Török I, Molnár A. [Mitochondrial myopathy (mono- and multisystem mitochondrial diseases)]. Orv Hetil 1992; 133:91-5. [PMID: 1732884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Four mitochondrial myopathy cases are reported. In addition to complaints, clinical and laboratory findings the changes in number, size, shape and in structure of the mitochondria in skeletal muscles are detailed. In three of their cases the disease is monosystemic, one case seems to be multisystemic in character: beside the morphologically proven muscle and liver changes it is likely that cardiac muscle and the central nervous system is also affected on the base of the clinical symptoms.
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Jakab K, Kelemen E, Váradi G, Török I. [Amphotericin B resistant severe hepato-splenic candidiasis, responding to fluconazole, in a patient following bone marrow transplantation]. Orv Hetil 1991; 132:643-5. [PMID: 2011389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A 23 year old woman with Philadelphia-positive chronic granulocytic leukaemia underwent a 3/4 HLA identical bone marrow transplantation. During the neutropenic period, a septic condition developed which was caused by Candida albicans. Administration of Amphotericin B for 63 day was ineffective including an attempt to give the drug through the truncus coeliacus. Finally the sepsis disappeared during fluconazole treatment.
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Strand D, Török I, Kalmes A, Schmidt M, Merz R, Mechler BM. Transcriptional and translational regulation of the expression of the l(2)gl tumor suppressor gene of Drosophila melanogaster. ADVANCES IN ENZYME REGULATION 1991; 31:339-50. [PMID: 1908614 DOI: 10.1016/0065-2571(91)90022-e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
By structural, biochemical and molecular genetic analyses, we have investigated the different mechanisms that control the expression of the lethal(2) giant larvae gene, a tumor suppressor gene of Drosophila melanogaster. Transcription of the l(2)gl gene is controlled by two highly identical promoters that result from the duplication of the 2.8 kb proximal portion of the gene. These two repeats are 96% homologous. Reverse genetic analysis has shown that each promoter can drive gene expression. In addition to the promoters, both repeats express two or three exons according to the pattern of splicing. The most distal exon in the second repeat is required because it contains the ATG initiating codon at the beginning of the open reading frame. The 3' untranslated region appears to contain motifs that specifically destabilize the transcript. Deletion of this region results in the formation of more stable mRNAs. The l(2)gl gene is characterized by an unusual codon usage that may reflect an enhanced translation efficiency by moderating the strength of pairing between codons and anticodons and may therefore increase the expressivity of this gene. Analysis of the spatio-temporal expression of the l(2)gl transcripts and proteins has shown that transcripts and proteins are produced ubiquitously during early embryogenesis, at a time when expression of the gene is required for preventing tumorigenesis. In the second half of embryogenesis, l(2)gl expression becomes restricted to tissues that do not show any phenotypic alteration in mutant animals. The l(2)gl protein exhibits two distinct intracellular localizations. It is preferentially found free in the cytoplasm but can become associated with the inner face of the plasma membrane where it is restricted to domains facing contiguous cells. In particular, the l(2)gl protein is absent from the basal and apical domains of the plasma membrane. The aim of the current research is directed towards understanding the functional relevance of the l(2)gl protein binding to the plasma membrane and its role in the control of cell proliferation and differentiation.
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Dezsö B, Török I, Rosik LO, Sweet F. Human ovarian cancers specifically bind daunorubicin-OC-125 conjugate: an immunofluorescence study. Gynecol Oncol 1990; 39:60-4. [PMID: 2227573 DOI: 10.1016/0090-8258(90)90399-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This study was designed to test the specific binding to human ovarian serous adenocarcinomas of a drug-antibody conjugate [daunorubicin (DNR-OC-125], made from a new analog (PIPP-DNR) of daunorubicin that chemically links the drug to monoclonal antibodies. We recently reported that the DNR-OC-125 conjugate is selectively toxic in vitro to dividing cell populations of the human ovarian cancer cell lines SK-OV-3 and OVCAR-3 that express the CA-125 antigen [F. Sweet, L. O. Rosik, G. M. Sommers, and J. L. Collins, Gynecol. Oncol. 34, 305-311 (1989)]. In the present study, immunofluorescence data show that the DNR-OC-125 conjugate has high affinity and specificity for proliferating malignant cells from human ovarian tumors. The results demonstrate that the DNR-OC-125 conjugate retains the specific binding to CA-125 antigenic sites characteristic of the OC-125 monoclonal antibody moiety. The DNR-OC-125 conjugate selectively binds to CA-125 antigen-positive ovarian cancerous tissue in both cryostat and paraffin-embedded tissue sections. This is consistent with the earlier in vitro data from dividing populations of two human ovarian cancer cell lines that revealed retention by the DNR-OC-125 conjugate of both the specificity due to OC-125 and the cytotoxicity of daunorubicin. The present immunofluorescence studies in the DNR-OC-125 conjugate is tested on human ovarian serous tumors indicate that the OC-125 monoclonal antibody can indeed serve as a cancer-targeting carrier for daunorubicin and its analogs.
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Merz R, Schmidt M, Török I, Protin U, Schuler G, Walther HP, Krieg F, Gross M, Strand D, Mechler BM. Molecular action of the l(2)gl tumor suppressor gene of Drosophila melanogaster. ENVIRONMENTAL HEALTH PERSPECTIVES 1990; 88:163-167. [PMID: 2125557 PMCID: PMC1567978 DOI: 10.1289/ehp.9088163] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Tumor suppressor genes act as recessive determinants of cancer. These genes contribute to the normal phenotype and are required for regulating cell growth and differentiation during development. Inactivation of tumor suppressor genes leads to an unrestricted pattern of growth in specific cell types. In Drosophila, a series of genes have been identified that cause tissue-specific tumors after mutation. Of these, the lethal(2)giant larvae (l(2)gl) gene is the best studied. Homozygous l(2)gl mutations cause the development of malignant tumors in the brain and the imaginal discs. Genomic DNA from the l(2)gl locus has been cloned, introduced back into the genome of l(2)gl-deficient animals, and shown to reinstate normal development. The nucleotide sequence of the l(2)gl gene has been determined, as well as the sequences of two classes of transcripts. Analysis of the spatial distribution of both l(2)gl transcripts and proteins revealed that during early embryogenesis the l(2)gl gene is uniformly expressed in all cells and tissues. In late embryos, the l(2)gl expression becomes gradually restricted to tissues presenting no morphological or neoplastic alteration in the mutant animals. Further mosaic experiments revealed that l(2)gl gene loss can cause three distinct phenotypes: neoplastic transformation, abnormal differentiation, and normal development. These phenotypes depend upon the extent of gene activity in the stem cells prior to the formation of l(2)gl- clones. These analyses indicate that the critical period for the establishment of tumorigenesis occurs during early embryogenesis at a time when the l(2)gl expression is most intense in all cells.
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Jakab K, Kelemen E, Prinz G, Török I. Amphotericin-resistant invasive hepatosplenic candidiasis controlled by fluconazole. Lancet 1990; 335:473-4. [PMID: 1968194 DOI: 10.1016/0140-6736(90)90706-b] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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48
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Abstract
The authors report a case of tinea capitis in a woman aged 49, with a previous history of discoid lupus erythematosus. The pathogenic agent was Microsporum canis. The patient was cured after two months therapy with griseofulvin and local antimycotics.
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49
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Palló N, Török I, Paál T. [Chromatographic separation and simultaneous determination of sulfathiourea, sulfamethoxypyridazine and sulfadimidine]. ACTA PHARMACEUTICA HUNGARICA 1988; 58:105-13. [PMID: 3245446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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50
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Dvorácsek E, Kassai Z, Török I. [Correlation between serum levels of steroid sex hormones and bilirubin in the newborn infant]. Orv Hetil 1988; 129:289-91. [PMID: 3347479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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