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1.
Rozhl Chir ; 100(1): 21-26, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33691419

RESUMO

INTRODUCTION: Thyroid surgery in children is a rare operation. The aim of our paper is to point out the specifics of thyroid surgery in children. METHODS: Retrospective analysis of patients hospitalized at the Department of Paediatric Surgery, Faculty of Medicine, Comenius University and National Institute of Childrens Diseases in Bratislava during a 10-year period (20072016) who underwent thyroid surgeries. RESULTS: The retrospective analysis included 81 patients: 66 (81%) girls and 15 (19%) boys. The mean age of the patients was 14 years ±8 months (range 418 years). The most common indications for thyroid surgery were: a nodule in 36 (44.4%) patients, Graves Basedow thyrotoxicosis in 19 (23.5%) patients, and suspected thyroid carcinoma in 11 (13.6%) patients. Cervical lymph node metastases (mts) were diagnosed in 9 (11.1%) patients, and distant pulmonary metastases in 5 (6.17%) patients. Total thyroidectomy (TTE) was performed in 43 (53%) patients, total lobectomy (TL) in 20 (24.7%) patients. Extended surgery on regional lymph nodes was performed in 9 (11.1%) patients. Eight (9.9%) patients underwent reoperation. A total of 12 (14.8%) patients experienced postoperative complications. Unilateral transient recurrent laryngeal nerve (RLN) paralysis occurred in 2 patients, and permanent in one patient. Transient postoperative hypoparathyroidism with hypocalcaemia was reported in 8 (9.9%) patients; no permanent condition of this type was observed. CONCLUSION: Multidisciplinary collaboration ensures that optimal surgical results are achieved in the patients. Experience of the surgeon performing thyroid surgery in children remains crucial.


Assuntos
Neoplasias da Glândula Tireoide , Paralisia das Pregas Vocais , Criança , Feminino , Humanos , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/efeitos adversos
2.
Vestn Otorinolaringol ; 86(1): 82-89, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33720658

RESUMO

Hearing impairment is the most common sensory impairment that is seen among adults and children. The frequency of congenital hearing loss is well-known due to implementation of newborn hearing screening. Hearing may change throughout a lifetime due to different factors and, therefore, the number of hearing impaired children increases with age. Introduction of universal newborn hearing screening has enabled earlier detection of hearing loss including unilateral and minimal disorders. Nevertheless, despite significant progress made in this field, there is still a group of hearing impairments that stay undiagnosed timely. Auditory neuropathy spectrum disorders, late-onset hearing loss, low-frequency and minimal hearing impairment are sometimes missed in newborn hearing screening or they manifest later. These types of hearing disorders are covered in detail in this review as well as possible ways of increasing the effectiveness of early diagnosis.


Assuntos
Perda Auditiva Neurossensorial , Triagem Neonatal , Criança , Audição , Transtornos da Audição , Testes Auditivos , Humanos , Recém-Nascido
3.
Ter Arkh ; 93(7): 770-777, 2021 Jul 23.
Artigo em Russo | MEDLINE | ID: mdl-36286727

RESUMO

BACKGROUND: Mantle cell lymphoma (MCL) is a rare and clinically aggressive lymphoma subtype. Current approaches have greatly improved patients outcomes, but relapse is inevitable. In phase IIIII clinical trials, ibrutinib has shown significant activity in patients with relapsed or refractory (R/R) MCL. AIM: To assess efficacy and toxicity of ibrutinib monotherapy in patients with R/R MCL in routine practice outside of clinical trials. MATERIALS AND METHODS: The study enrolled patients with confirmed R/R MCL who had received at least one line of previous chemotherapy. ECOG 24, cytopenia, infectious complications, hemorrhagic syndrome were not exclusion criteria. Patients received daily oral ibrutinib 560 mg until progression or unacceptable toxicity. RESULTS: From May 2015 to September 2020 ibrutinib therapy was started in 106 patients with R/R MCL in 16 regions of Russia. The median age was 66 years; ECOG2 18%, blastoid variant (or Ki6740% or WBC50109/l) 43%. The median number of previous treatment lines was 2 (111). The ORR was 78.4% (CRR 27.4%). The median PFS was 13.6 months and OS 23.2 months. In the blastoid group the median PFS was 4.4 months vs 36.5 months in the alternative group (p0.001), the median OS 9.0 vs 41.0 (p=0.001). The median OS of patients after progression on ibrutinib was 3.2 months. The common complications are hemorrhages (63%), diarrhea (62%), myalgia and muscle cramps (60%), infections (31%), skin and nail toxicity 15%, arrhythmia 8%. None of recipients had to completely discontinue ibrutinib therapy due to complications. CONCLUSION: Ibrutinib is effective and well tolerated in routine practice of R/R MCL treatment and our results are consistent with international clinical trials. The favorable toxicity profile and the high response rate made it possible to prescribe ibrutinib in severe somatic status, cytopenia, and even in the presence of infectious complications.


Assuntos
Adenina , Linfoma de Célula do Manto , Recidiva Local de Neoplasia , Piperidinas , Idoso , Humanos , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Piperidinas/uso terapêutico , Piperidinas/toxicidade , Adenina/análogos & derivados , Adenina/uso terapêutico , Adenina/toxicidade , Federação Russa , Ensaios Clínicos como Assunto
4.
Rozhl Chir ; 97(3): 139-144, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29589458

RESUMO

Minimally invasive techniques have now become standard for the treatment of many surgical conditions in children. There are a few studies that describe the utility of laparoscopy in BAT in children. In this article, we describe the complete laparoscopic surgical treatment of two patients after a single blunt abdominal trauma, both with bowel perforation. In both cases, the perforation was identified and closed, one laparoscopically with an ongoing suture, the second jejune perforation was closed by laparoscopic-assisted techniques. Both patients had an uneventful postoperative recovery. Therapeutic laparoscopic treatment of patients with upper gastrointestinal perforation is feasible. We hypothesize, that diagnostic laparoscopy provides important information for the treatment of children with abdominal trauma and is accompanied by improved diagnostic accuracy, reduction of nontherapeutic laparotomy rates, and a reduction of morbidity. Minimally invasive surgery in children after BAT is suitable for hemodynamic stable patients, could improve pain scores, cosmetic effect, shorter hospital stays, shorter operative times and shorter return to school/activities. However, at any point in the patients care, in case the unstable hemodynamic is encountered, exploratory laparotomy is the procedure of choice.Key words: miniinvasive surgery blunt abdominal trauma - laparoscopy bowel perforation.


Assuntos
Traumatismos Abdominais , Perfuração Intestinal , Laparoscopia , Ferimentos não Penetrantes , Traumatismos Abdominais/complicações , Traumatismos Abdominais/cirurgia , Criança , Humanos , Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgia , Laparotomia , Estudos Retrospectivos , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/cirurgia
5.
Klin Onkol ; 30(Supplementum1): 166-169, 2017.
Artigo em Tcheco | MEDLINE | ID: mdl-28471197

RESUMO

BACKGROUND: Myeloid-derived suppressor cells (MDSCs) are heterogenic population of multipotent progenitors of myeloid lineage. For their immunosuppressive effect, MDSC are responsible for tumour escape from the host immune surveillance. Furthermore, MDSCs support tumour by promotion of angiogenesis and metastasis. Membrane markers of human MDSCs are myeloid markers CD11b and CD13, these cells are HLA-Drlow/- and expression of CD15 or CD14 differentiate them into granulocytic (Gr-MDSCs) and monocytic (Mo-MDSCs), resp. PATIENTS AND METHODS: Using flow cytometry, we investigated Mo-MDSC counts in peripheral blood of non-cancer individuals - control group (n = 61), breast (n = 39) and colorectal (n = 52) cancer patients. These cells were detected as CD45+CD11b+CD33+CD14+HLA-Drlow/- and quantified as percentage of total white blood cells and as absolute count. RESULTS: In control group, circulating Mo-MDSCs was gender-and age-independent and the average value was 1.09% and 0.073 × 109/l. Breast cancer patients had higher circulating Mo-MDSCs compared to control group with average values: 3.57% and 0.229 × 109/l (p < 0.001) and we also observed increase in Mo-MDSC number after granulopoietic growth factors administration (p = 0.043). Colorectal cancer patients had higher average number of circulating Mo-MDSCs compared to control group: 1.71% a 0.125 × 109/l (p = 0.003) and its number did not correlate with tumour clinicopathological stage, localization of primary tumour (colon vs. rectum), site (left vs. right) and microsatellite instability. CONCLUSION: Increased number of MDSCs in circulation and within tumour microenvironment has been associated with immune suppression and tumour progression. Colorectal cancer patients at diagnosis showed higher circulating Mo-MDSCs possibly reflecting immunosuppressive effect of tumour microenvironment. Change of Mo-MDSC number from baseline level need to be evaluated in the context of CRC patients outcome. Recombinant granulopoietic growth factors increase number of circulating Mo-MDSCs and the effect of this phenomenon on cancer prognosis remains to be elucidated.Key words: myeloid-derived suppressor cells - colorectal cancer - breast cancer - immunology - immunosuppression - G-CSF This work was supported by MEYS by NPU I (LO1413), grant AZV 16-31966A and MH DRO 00209805. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 11. 3. 2017Accepted: 26. 3. 2017.


Assuntos
Células Supressoras Mieloides/fisiologia , Neoplasias/imunologia , Feminino , Humanos , Masculino , Neoplasias/patologia , Evasão Tumoral , Microambiente Tumoral
6.
Klin Onkol ; 28 Suppl 2: 2S60-8, 2015.
Artigo em Tcheco | MEDLINE | ID: mdl-26374160

RESUMO

γδ T cells present a minor population of the T cell family which basically differs in construction of their T cell receptor (TCR). Thanks to the features of γδ TCR, these cells can acquire unique effector functions and play a specific role (not only) in antitumor immune response. In this article, we describe the basic characteristics of this cell population and their connection to cancer. In the experimental part we performed exploratory analysis of circulating γδ T cells in reference population and comparison with melanoma and breast carcinoma patients. The median percentage of γδ T cells from all lymphocytes was 2.9% (interquartile range-IQR 1.7-4%). The median absolute numbers of γδ cells per liter of blood was 5.05×10(7) (IQR 2.9-7.84×10(7)). The median percentage of γδ cells between all CD3 T cells was 3.9% (IQR 2.3-5.6%). No correlation between γδ T cells levels and gender or age was observed in reference population. Detailed immunophenotyping was also conducted describing representation of memory subsets (using CD45RO and CD27 markers) and presence of surface markers HLADr, CD69, CD25, CD28, CCR7, CTLA 4, ICOS, PD 1L and PD 1 between γδ T cells of the controls and breast carcinoma patients. From this analysis, it is evident that γδ T cells do not represent a uniform population but they differ in surface markers as well as in their effector functions.


Assuntos
Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/fisiologia , Linfócitos T/fisiologia , Animais , Humanos , Imunofenotipagem
7.
Gig Sanit ; 94(8): 77-81, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26856180

RESUMO

In the article there are presented data of the system analysis of hygienic properties of polyguanidines (PAG) as an innovative class of domestic microbicidal chemical long-acting compounds synthesized in the domestic scientific institution--Institute ofenvironmental and technological problems, and also delivered on their base new disinfectants. Submitted proceedings of microbiological studies indicate to the antimicrobial action of PA G against Gram-negative and Gram-positive bacteria, viruses, dermatophytes, yeasts, fungi, including pathogens, as well infectious agent of swine and legionellosis. The data of toxicological studies of PAG and a number of derivative disinfectants justify their hygienic safety in dependence on the chemical nature of the used anion (A), the composition and structure of the polymer chain and also the content of residual monomers. All this characterizes PAG as a very promising group of compounds for the use in the form of independent disinfectants and as antimicrobial additives and auxiliaries in such means for different purposes.


Assuntos
Anti-Infecciosos/farmacologia , Infecções Bacterianas/prevenção & controle , Desinfetantes/farmacologia , Higiene/normas , Animais , Modelos Animais de Doenças , Humanos , Suínos
8.
Klin Med (Mosk) ; 91(10): 57-60, 2013.
Artigo em Russo | MEDLINE | ID: mdl-25696953

RESUMO

Caroli's disease is a rare congenital condition characterized by segmental non-obstructive fibrocystic dilation of intrahepatic bile ducts. Dilated ducts may be infected and contain stones. This review of the modern literature describes few known cases of the disease, analyses its clinical features and results of treatment. The principal diagnostic methods include visualization by ultrasound study, CT, MRT, retrograde and transhepatic cholangiography. Surgical intervention is the method of choice for the treatment of the disease including resection of liver, placement of hepatico-jejunal anastomoses and transplantation. The choice depends on the extent of the lesion and anticipated complications. The authors' observation of the patient with Caroli's disease in a 35 year-old woman is presented. It was successfully treated by left-hand bisegmentectomy even though the disease was diagnosed 14 years after the first symptoms. It is recommended that the disease, even if a rare one, should be included in the algorithm of differential diagnostics ofrecurrent abdominal pain with manifestations of cholestasis or fever of an unknown origin.


Assuntos
Doença de Caroli/diagnóstico , Adulto , Doença de Caroli/cirurgia , Feminino , Humanos
9.
Bioorg Khim ; 37(6): 844-53, 2011.
Artigo em Russo | MEDLINE | ID: mdl-22497084

RESUMO

The synthesis of asymmetric meso-aryl-substituted porphyrins containing three 4-methoxycarbonylphenyl groups, and as a forth substituent 4-hydroxyphenyl or 4-hydroxy-3- methoxyphenyl radicals, or the isomeric 3- and 4-pyridyl substituents is described. O-alkyl derivatives of 4-hydroxyl residue are obtained. The ytterbium complexes ofthese porphyrins were synthesized and studied their luminescence spectral properties were studied. A significant difference in the lifetimes of the excited state ofytterbium complexes of esters and acids of asymmetric porphyrins is demonstrated.


Assuntos
Porfirinas/química , Porfirinas/síntese química , Itérbio/química , Isomerismo , Luminescência
10.
Stud Mycol ; 61: 39-49, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19287525

RESUMO

Dothideaceous black yeast-like fungi (BYF) are known to synthesise DHN-melanin that is inhibited by the systemic fungicide tricyclazole. The final step of the DHN melanin pathway is the conjoining of 1,8-DHN molecules to form the melanin polymer. There are several candidate enzymes for this step, including phenoloxidases such as tyrosinase and laccases, peroxidases, and perhaps also catalases. We analysed the type polyphenoloxidases that are involved in biosynthesis of BYF melanins. For that purpose we used substrates of o-diphenoloxidases (EC 1.10.3.1.): 4-hydroxyphenyl-pyruvic acid, L-beta-phenyllactic acid, tyrosine, pyrocatechol, 3,4-dihydroxyphenylalanine and homogentisic acid, as well as substrates of p-diphenoloxidases (EC 1.10.3.2.): syringaldazine, resorcinol, p-phenylenediamine, phloroglucinol, guaiacol and pyrogallic acid. Fourteen strains of black yeasts originating from different natural biotopes were investigated. The tested strains could be divided into four groups based on their ability to produce dark pigments when cultivated on aromatic substrates of o- and on p-diphenoloxidases. It was established that syringaldazine, pyrogallic acid and 4-hydrophenyl-pyruvic acid, beta-phenyllactic acid optimally promote melanin biosynthesis. Average intensity of pigmentation of all strains studied was minimal when guaiacol was used as a substrate. The present investigation indicates that the melanisation process may involve more enzymes and more substrates than those commonly recognised. Black yeasts are likely to contain a multipotent polyphenoloxidase.

11.
Oncogene ; 27(9): 1218-30, 2008 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17724470

RESUMO

To better understand the dual, tumour-suppressive and tumour-promoting function of transforming growth factor-beta (TGFbeta), we analysed mammary epithelial NMuMG cells in response to short and long-term TGFbeta exposure. NMuMG cells became proliferation-arrested and apoptotic after exposure to TGFbeta for 2-5 days, whereas surviving cells underwent epithelial-mesenchymal transition (EMT). After chronic TGFbeta exposure (2-3 weeks), however, NMuMG cells became resistant to proliferation arrest and apoptosis, showing sustained EMT instead (TD cells). EMT was fully reversed by a pharmacologic TGFbeta-receptor-I kinase inhibitor or withdrawal of TGFbeta for 6-12 days. Interestingly, both cell cycle arresting/proapoptotic (Smads, p38 kinase) and antiapoptotic, proliferation and EMT-promoting signalling pathways (PI3K-PKB/Akt, ERK) were co-suppressed to low, but significant levels. Except for PI3K-Akt, TGFbeta-dependent downregulation of these signalling pathways in transdifferentiated (TD) cells was fully reversed upon TGFbeta withdrawal, together with partial re-induction of proliferation arrest and apoptosis. Co-injection of non-tumorigenic NMuMG cells with tumour-forming CHO cells oversecreting exogenous TGFbeta1 (CHO-TGFbeta1) allowed outgrowth of epithelioid cells in CHO-TGFbeta1 cell-induced tumours. These epithelial islands enhanced CHO-TGFbeta1 tumour cell proliferation, possibly due to chemokines (for example, JE/MCP-1) secreted by NMuMG/TD cells. We conclude that suppression of antiproliferative, proapoptotic TGFbeta signalling in TD cells may permit TGFbeta-dependent proliferation, survival and EMT-enhancing signalling pathways to act at low levels. Thus, TGFbeta may modulate its own signalling to facilitate switching from tumour suppression to tumour progression.


Assuntos
Apoptose , Transformação Celular Neoplásica/patologia , Células Epiteliais/patologia , Glândulas Mamárias Animais/patologia , Mesoderma/patologia , Transdução de Sinais/fisiologia , Proteínas Smad/antagonistas & inibidores , Fator de Crescimento Transformador beta/fisiologia , Animais , Apoptose/genética , Células CHO , Técnicas de Cultura de Células , Linhagem Celular , Transformação Celular Neoplásica/metabolismo , Cricetinae , Cricetulus , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Genes Supressores de Tumor/fisiologia , Glândulas Mamárias Animais/metabolismo , Mesoderma/citologia , Mesoderma/metabolismo , Camundongos , Proteínas Smad/fisiologia , Fator de Crescimento Transformador beta/genética
12.
Mol Biol (Mosk) ; 40(1): 61-73, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16523693

RESUMO

In order to elucidate the molecular-genetic relations of some Lacerta s. str. lizard populations, subspecies and species in comparison with some other genera we used methods revealing four types of nuclear DNA markers. Among these were taxonprint, RAPD, Inter-MIR-PCR markers and also satellite DNA monomer sequences. The aim was to compare the phylogeny and systematics of this reptilian group based on morphological and molecular criteria. This problem has a general importance for understanding a speciation process. Our results show a good correlation between both approaches when genera and species levels were studied. Systematic status of five subspecies of L. agilis were supported but not in all cases, some subspecies have no meaningful genetic differences by three types of molecular markers, but all of them were differed by RAPD markers. The data confirm the subdivision of L. agilis populations into west and east clades proposed by other authors earlier on the basis of mitochondrial DNA and morphology. The population structure of one of the subspecies--L. agilis exigua, was studied on a number of populations distributed from Ural region up to Kabardino-Balkaria by IMP method. There were no significant differences among these 14 populations investigated. The data testify the rapid distribution of the species after the end of Pleistocene glaciation.


Assuntos
Variação Genética , Lagartos/genética , Animais , Sequência de Bases , DNA Satélite/genética , Evolução Molecular , Marcadores Genéticos , Genética Populacional , Lagartos/classificação , Dados de Sequência Molecular , Filogenia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie
13.
Med Parazitol (Mosk) ; (2): 45-50, 2003.
Artigo em Russo | MEDLINE | ID: mdl-12886594

RESUMO

The paper proposes a methodology based on the operation study theory, which can compare disinfectants by a combination of all their properties, which is integrated in the cost of tackling a disinfectological task rather than by the presence or magnitude of these or those useful properties.


Assuntos
Desinfetantes/normas , Desinfecção/normas , Análise de Sistemas , Custos e Análise de Custo , Desinfecção/economia , Estudos de Avaliação como Assunto
14.
Klin Med (Mosk) ; 81(4): 61-3, 2003.
Artigo em Russo | MEDLINE | ID: mdl-12785228

RESUMO

A case of right and left ventricular myocardial infarction in infectious endocarditis of the aortic valve in an injected drug abuser is reported. The infarction was diagnosed only in autopsy. Diagnostic difficulties are discussed. The literature on the problem is listed.


Assuntos
Endocardite Bacteriana/complicações , Infarto do Miocárdio/complicações , Disfunção Ventricular Direita/complicações , Adulto , Evolução Fatal , Humanos , Masculino
16.
Hum Genet ; 109(2): 167-77, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11511922

RESUMO

The t(11;22)(q23;q11) translocation is the most common recurrent balanced translocation described in humans. Carriers are phenotypically normal and often go undetected until diagnosis as a result of infertility investigations or following the birth of chromosomally unbalanced offspring. Efficient diagnostics of t(11;22) is important for children born to carriers of the translocation and for prenatal and pre-implantation diagnosis. The translocation breakpoint on chromosome 22 is located within a region containing low copy repeats, and this site is one of the last unfilled gaps in the sequence of this chromosome. This autosome harbors multiple other low copy repeats, which have been entirely sequenced. We report a combined sequencing and fiber FISH breakpoint characterization in five translocation carriers. From one carrier a cosmid library was constructed, and two chimeric cosmids (cos4_der11 and cos6_der22) were sequenced, which showed that strong palindromes (or inverted repeats) occur on both chromosomes. The translocation breakpoints occur at the tip of both inverted repeats. The palindrome on chromosomes 22 and 11 is composed of 852 and 166 bases, respectively. Four additional carriers were studied using fiber FISH with a resolution limit of 2 kb. Analysis of breakpoints on the DNA sequence level, or at the level of fiber FISH, indicate that they occur at the same position on both chromosomes in all five carriers. Using cos6_der22, PAC 158L19 and BAC 3009A19, we demonstrate that FISH is an attractive alternative in molecular diagnostics of t(11;22), as PCR assays are not reliable, due to the presence of numerous copies of low copy repeats.


Assuntos
Quebra Cromossômica/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 22/genética , Translocação Genética , Adulto , Sequência de Bases , Cromossomos Artificiais Bacterianos/genética , Cosmídeos , Primers do DNA/química , Feminino , Testes Genéticos , Biblioteca Genômica , Humanos , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
17.
Genetika ; 37(4): 456-66, 2001 Apr.
Artigo em Russo | MEDLINE | ID: mdl-11421118

RESUMO

The Restriction On Computer (ROC) program (freely available at http://www.mcb.harvard.edu/gilbert/ROC) was developed and used to analyze the restriction fragment length distribution in the human genome. In contrast to other programs searching for restriction sites, ROC simultaneously analyzes several long nucleotide sequences, such as the entire genomes, and in essence simulates electrophoretic analysis of DNA restriction fragments. In addition, this program extracts and analyzes DNA repeats that account for peaks in the restriction fragment length distribution. The ROC analysis data are consistent with the experimental data obtained via in vitro restriction enzyme analysis (taxonomic printing). A difference between the in vitro and in silico results is explained by underrepresentation of tandem DNA repeats in genomic databases. The ROC analysis of individual genome fragments elucidated the nature of several DNA markers, which were earlier revealed by taxonomic printing, and showed that L1 and Alu repeats are nonrandomly distributed in various chromosomes. Another advantage is that the ROC procedure makes it possible to analyze the nonrandom character of a genomic distribution of short DNA sequences. The ROC analysis showed that a low poly(G) frequency is characteristic of the entire human genome, rather than of only coding sequences. The method was proposed for a more complex in silico analysis of the genome. For instance, it is possible to simulate DNA restriction together with blot hybridization and then to analyze the nature of markers revealed.


Assuntos
Genoma Humano , Software , Sequência de Bases , Humanos , Dados de Sequência Molecular , Mapeamento por Restrição/métodos
18.
Nucleic Acids Res ; 29(7): 1464-9, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11266547

RESUMO

Of the rules used by the splicing machinery to precisely determine intron-exon boundaries only a fraction is known. Recent evidence suggests that specific short sequences within exons help in defining these boundaries. Such sequences are known as exonic splicing enhancers (ESE). A possible bioinformatical approach to studying ESE sequences is to compare genes that harbor introns with genes that do not. For this purpose two non-redundant samples of 719 intron-containing and 63 intron-lacking human genes were created. We performed a statistical analysis on these datasets of intron-containing and intron-lacking human coding sequences and found a statistically significant difference (P = 0.01) between these samples in terms of 5-6mer oligonucleotide distributions. The difference is not created by a few strong signals present in the majority of exons, but rather by the accumulation of multiple weak signals through small variations in codon frequencies, codon biases and context-dependent codon biases between the samples. A list of putative novel human splicing regulation sequences has been elucidated by our analysis.


Assuntos
Processamento Alternativo , Elementos Facilitadores Genéticos/genética , Éxons/genética , Genes/genética , Íntrons/genética , Composição de Bases , Bases de Dados Factuais , Humanos , Fases de Leitura Aberta , Proteínas/genética , Estatística como Assunto
19.
Mol Gen Genet ; 264(5): 588-94, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11212913

RESUMO

The endogenous Drosophila melanogaster retrovirus gypsy (mdg4) forms virus-like particles (VLPs) which are found as extracellular particles in the medium used to culture D. melanogaster cells. The D. hydei somatic cell line DH14, which does not harbour gypsy sequences, was exposed to D. melanogaster VLPs. Subsequent PCR and Southern analysis revealed that gypsy elements had penetrated into the D. hydei cells, suggesting interspecific transmission of the retrovirus. A D. hydei cell line containing gypsy sequences was established and grown in a mixed culture together with the G418-resistant D. hydei cell line DH33, and gypsy was shown to be transmitted from cell to cell. The proportion of cells carrying gypsy increased with time. The rate of gypsy invasion of the lines DH14 and DH33 was 10(-3) and 10(-2) per cell per generation, respectively. The results demonstrate the possibility of interspecific horizontal transfer of gypsy in the form of its VLPs.


Assuntos
Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Drosophila/metabolismo , Retroelementos , Retroviridae/fisiologia , Animais , Southern Blotting , Técnicas de Cultura de Células , Linhagem Celular , Técnicas de Cocultura , Drosophila/virologia , Drosophila melanogaster/virologia , Hibridização In Situ , Reação em Cadeia da Polimerase , Especificidade da Espécie
20.
J Mol Biol ; 305(1): 33-48, 2001 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-11114245

RESUMO

Centromeric region of human chromosome 21 comprises two long alphoid DNA arrays: the well homogenized and CENP-B box-rich alpha21-I and the alpha21-II, containing a set of less homogenized and CENP-B box-poor subfamilies located closer to the short arm of the chromosome. Continuous alphoid fragment of 100 monomers bordering the non-satellite sequences in human chromosome 21 was mapped to the pericentromeric short arm region by fluorescence in situ hybridization (alpha21-II locus). The alphoid sequence contained several rearrangements including five large deletions within monomers and insertions of three truncated L1 elements. No binding sites for centromeric protein CENP-B were found. We analyzed sequences with alphoid/non-alphoid junctions selectively screened from current databases and revealed various rearrangements disrupting the regular tandem alphoid structure, namely, deletions, duplications, inversions, expansions of short oligonucleotide motifs and insertions of different dispersed elements. The detailed analysis of more than 1100 alphoid monomers from junction regions showed that the vast majority of structural alterations and joinings with non-alphoid DNAs occur in alpha satellite families lacking CENP-B boxes. Most analyzed events were found in sequences located toward the edges of the centromeric alphoid arrays. Different dispersed elements were inserted into alphoid DNA at kinkable dinucleotides (TG, CA or TA) situated between pyrimidine/purine tracks. DNA rearrangements resulting from different processes such as recombination and replication occur at kinkable DNA sites alike insertions but irrespectively of the occurrence of pyrimidine/purine tracks. It seems that kinkable dinucleotides TG, CA and TA are part of recognition signals for many proteins involved in recombination, replication, and insertional events. Alphoid DNA is a good model for studying these processes.


Assuntos
Autoantígenos , Centrômero/genética , Cromossomos Humanos Par 21/genética , DNA Satélite/genética , Proteínas de Ligação a DNA , Mutagênese Insercional/genética , Conformação de Ácido Nucleico , Recombinação Genética/genética , Elementos Alu/genética , Sequência de Bases , Sítios de Ligação , Centrômero/química , Centrômero/metabolismo , Proteína B de Centrômero , Proteínas Cromossômicas não Histona/metabolismo , Deleção Cromossômica , Inversão Cromossômica , Cromossomos Humanos Par 21/química , Cromossomos Humanos Par 21/metabolismo , Biologia Computacional , Troca Genética/genética , Replicação do DNA/genética , DNA Satélite/química , DNA Satélite/metabolismo , Bases de Dados como Assunto , Repetições de Dinucleotídeos/genética , Humanos , Hibridização in Situ Fluorescente , Linfócitos , Mutação/genética , Reação em Cadeia da Polimerase
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