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1.
Acta Gastroenterol Belg ; 86(3): 499-501, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37814569

RESUMO

Adenocarcinomas of the ampulla of Vater represent only 0.2% of all gastrointestinal cancers. Due to the low incidence no large clinical trials evaluating efficacy of treatments are available. Adjuvant therapy is often administered in patients with stage IB or higher. Oxaliplatin is considered as an effective and well tolerated therapeutic option. Adverse events associated with this therapy include cardio-, neuro-, nephrotoxicity and myelosuppression. Previously granulomatous pulmonary and liver manifestations have been described in oxaliplatin-based chemotherapy. In this report peritoneal manifestation of granulomatous disease associated with oxaliplatin is described for the first time. Sarcoidlike reactions may be misinterpreted as tumour progression or metastatic disease, and may consequently result in over-treatment.


Assuntos
Adenocarcinoma , Ampola Hepatopancreática , Neoplasias do Ducto Colédoco , Doenças Peritoneais , Humanos , Oxaliplatina/efeitos adversos , Ampola Hepatopancreática/patologia , Adenocarcinoma/patologia , Neoplasias do Ducto Colédoco/tratamento farmacológico , Neoplasias do Ducto Colédoco/etiologia , Neoplasias do Ducto Colédoco/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
2.
Genetika ; 44(5): 713-6, 2008 May.
Artigo em Russo | MEDLINE | ID: mdl-18672806

RESUMO

Genome sizes of Pseudomonas aeruginosa phages phiKZ and EL earlier determined by sequence analysis were shown to correspond to sizes of their DNAs assessed by pulse-electrophoresis (PFGE). Putative "redundant" genes in phiKZ phage genome are supposed to control functions promoting vigorous growth of the phage belonging to this species, compared to phages of EL species.


Assuntos
DNA Viral/química , Genes Virais , Fagos de Pseudomonas/genética , Pseudomonas aeruginosa/virologia , Eletroforese em Gel de Campo Pulsado
4.
Genetika ; 42(8): 1065-74, 2006 Aug.
Artigo em Russo | MEDLINE | ID: mdl-17025156

RESUMO

Study of two recently isolated giant bacteriophages Lu11 and OBP that are active on Pseudomonas putida var. Manila and Pseudomonas fluorescens, respectively, demonstrated their similarity in morphology, genome size, and size of phage particles, with giant bacteriophages of Pseudomonas aeruginosa assigned to the supergroup of phiKZ-like phages of the family Myoviridae designated in this manner according to the best studied phage phiKZ that belongs to the species of this group widely distributed in nature. Comparison of major polypeptide sizes of mature particles suggests the similarity of certain proteins in the phages examined. In OBP particles visualized with an electron microscope, an "inner body" was detected, which points to the specific DNA package intrinsic to phages of phiKZ group. In the meantime, phages Lul11 and OBP do not exhibit resemblance among themselves or with any of earlier described phiKZ-like phages in respect to other traits; particularly, they have no detectable DNA homology. Note that phage Lu11 of P. putida var. Manila exhibits very slight homology with phage Lin68 of the family of P. aeruginosa phiKZ-like phages detected only in blot hybridization. This suggests the possible involvement of these phages in interspecies recombination ("gene shuffling") between phages of various bacterial species. Results of partial sequencing of phage genomes confirmed the phylogenetic relatedness of phage OBP to phages of the phiKZ-supergroup, whereas phage Lu11 most probably belongs to a novel species that is not a member of supergroup phiKZ composition. The results of the study are discussed in terms of the evolution of these phages.


Assuntos
Fagos de Pseudomonas/genética , Fagos de Pseudomonas/fisiologia , Pseudomonas aeruginosa/virologia , Microbiologia do Solo , Genoma Viral/genética , Filogenia , Fagos de Pseudomonas/ultraestrutura , Análise de Sequência de DNA
5.
J Biotechnol ; 115(3): 249-60, 2005 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-15639087

RESUMO

Two family 11 endoxylanases (EC 3.2.1.8) were functionally displayed on the surface of bacteriophage M13. The genes encoding endo-1,4-xylanase I from Aspergillus niger (ExlA) and endo-1,4-xylanase A from Bacillus subtilis (XynA) were fused to the gene encoding the minor coat protein g3p in phagemid vector pHOS31. Phage rescue resulted in functional monovalent display of the enzymes as was demonstrated by three independent tests. Firstly, purified recombinant phage particles showed a clear hydrolytic activity in an activity assay based on insoluble, chromagenic arabinoxylan substrate. Secondly, specific binding of endoxylanase displaying phages to immobilized endoxylanase inhibitors was demonstrated by interaction ELISA. Finally, two rounds of selection and amplification in a biopanning procedure against immobilized endoxylanase inhibitor were performed. Phages displaying endoxylanases were strongly enriched from background phages displaying unrelated proteins. These results open perspectives to use phage display for analysing protein-protein interactions at the interface between endoxylanases and their inhibitors. In addition, this technology should enable engineering of endoxylanases into novel variants with altered binding properties towards endoxylanase inhibitors.


Assuntos
Aspergillus niger/enzimologia , Bacillus subtilis/enzimologia , Bacteriófago M13/enzimologia , Endo-1,4-beta-Xilanases/metabolismo , Proteínas de Membrana/metabolismo , Biblioteca de Peptídeos , Mapeamento de Interação de Proteínas/métodos , Aspergillus niger/genética , Bacillus subtilis/genética , Bacteriófago M13/genética , Clonagem Molecular , Endo-1,4-beta-Xilanases/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação Viral da Expressão Gênica/fisiologia , Engenharia de Proteínas/métodos , Proteínas Recombinantes/metabolismo
6.
Protein Pept Lett ; 12(7): 645-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16522177

RESUMO

Gene 17 product (gp17) of the Pseudomonas aeruginosa-infecting bacteriophage phiKMV shows in silico similarity to T7 DNA ligase. In a semi-quantitative activity assay, it is shown that gp17 is a functional, ATP-dependent DNA ligase, in spite of some structural differences related to DNA-binding properties). Enzymatic activity of His6-based purified expression product was optimised (4 degrees C at 24h for sticky end double-stranded DNA fragments) and estimated at 0.5 Weiss U/microg.


Assuntos
Bacteriófagos/enzimologia , DNA Ligases/metabolismo , Sequência de Aminoácidos , Bacteriófagos/genética , Biologia Computacional , Sequência Conservada , DNA Ligase Dependente de ATP , DNA Ligases/química , DNA Ligases/genética , DNA Ligases/isolamento & purificação , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência
7.
Genetika ; 41(4): 455-65, 2005 Apr.
Artigo em Russo | MEDLINE | ID: mdl-15909907

RESUMO

Bacteriophages of the family Myoviridae represent one of the most widespread domains of the biosphere substantially affecting the ecological balance of microorganisms. Interestingly, sequence analysis of genomic DNAs of large bacteriophages revealed many genes coding for proteins with unknown functions. A new approach is proposed to improve the functional identification of genes. This approach is based on comparing the genome sequence for phylogenetically and morphologically related phages showing no considerable homology at the level of genomic DNA. It is assumed that gene functions essential for the development of phages of a given family are conserved and that the corresponding genes code for similar orthologous proteins even when lacking sequence homology. The genome was sequenced and compared for two Pseudomonas aeruginosa giant bacteriophages, phiKZ and EL, which belong to a group of (phiKZ-related phages. A substantial difference in genome organization was observed, suggesting specific features of phage evolution. In addition, the problem of the minimal genome of the superfamily is discussed on the basis of the difference in size and structure between the phiKZ and EL genomes.


Assuntos
Evolução Molecular , Genoma Viral , Fagos de Pseudomonas/genética , Proteínas Virais/genética , Sequência de Bases , Dados de Sequência Molecular , Pseudomonas aeruginosa , Análise de Sequência de DNA
8.
Int J Radiat Biol ; 71(4): 429-33, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9154146

RESUMO

Human peripheral blood lymphocytes, irradiated in vitro, die by an apoptotic process. The number of apoptotic cells after in vitro gamma-irradiation (0, 0.1, 0.2, 1, 2 and 5 Gy) was measured by flow cytometry using Annexin V and DiOC6 (a cationic dye) after 24 and 48 h incubation. The mean dose-response curves for apoptosis of six healthy volunteers obtained with both methods were steep below 1 Gy and flatter at higher doses. A slightly higher number of apoptotic cells was observed with DiOC6, compared to Annexin V. This can be assigned to a minor DiOC6-int/PI- population. Forty-eight hour cultures contained higher numbers of apoptotic cells compared with 24 h cultures. For both culture times, DiOC6 and Annexin V detected a statistically significant difference between a control sample and a 0.1 Gy irradiated one, illustrating the high sensitivity of the methods.


Assuntos
Apoptose/efeitos da radiação , Linfócitos/efeitos da radiação , Anexina A5 , Carbocianinas , Células Cultivadas , Relação Dose-Resposta à Radiação , Citometria de Fluxo/métodos , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Raios gama , Humanos , Cinética , Linfócitos/patologia , Proteínas Recombinantes , Sensibilidade e Especificidade
9.
Pathol Res Pract ; 196(11): 783-90, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11186176

RESUMO

Limb-body wall complex (LBWC) is a rare, sporadic, congenital defect defined as a combination of at least two of three characteristics: 1. limb defects, 2. anterior body wall defects, and 3. exencephaly or encephalocoele with/without facial clefts. Three pathogenic mechanisms have been proposed: early amnion rupture, vascular disruption and embryonic dysgenesis. In this study we carried out the pathological evaluation of four fetuses with LBWC and their placentas. None of the cases had craniofacial defects. Three fetuses showed an abdominal wall defect with eventration of abdominal organs, cloacal exstrophy, absent external genitalia, abnormal internal genitalia, scoliosis and lower limb defects. One fetus showed failure of closure of both thoracic and abdominal walls with ectopia cordis, evisceration of left lung and abdominal organs, severe reduction defect of left arm, but normal colon, anus, bladder, genitalia and lower limbs. All cases had a short, malformed umbilical cord, incompletely covered by amnion. The umbilical vessels were embedded in an amniotic sheet which connected the skin margin of the anterior body wall defect to the placenta. These anomalies suggest an abnormal body stalk development as a pathogenic mechanism for LBWC. Prenatally, the abnormal fetoplacental attachment can be detected ultrasonographically by the end of the first gestational trimester. Postnatally, the examination of placenta, umbilical cord and membranes is crucial in confirming the diagnosis of LBWC.


Assuntos
Músculos Abdominais/anormalidades , Anormalidades Múltiplas/patologia , Deformidades Congênitas dos Membros/patologia , Placenta/patologia , Cordão Umbilical/patologia , Anormalidades Múltiplas/etiologia , Adulto , Feminino , Idade Gestacional , Humanos , Deformidades Congênitas dos Membros/etiologia , Gravidez
10.
JBR-BTR ; 97(2): 81-3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25073236

RESUMO

Pseudoangiomatous stromal hyperplasia is a benign mesenchymal tumor of the breast. It is a rare condition and until a few years mainly described in pathological and surgical literature. Here, we provide a case report of PASH and an overview of its radiological features.


Assuntos
Angiomatose/diagnóstico , Doenças Mamárias/diagnóstico , Neoplasias da Mama/diagnóstico , Mama/patologia , Hiperplasia/diagnóstico , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Adulto , Biópsia por Agulha , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem/métodos , Ultrassonografia Mamária/métodos
17.
Arch Virol ; 152(8): 1467-75, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17534690

RESUMO

Little is known about the bacteriophage proteins expressed immediately after infection of the host cell. Most of these early proteins are probably involved in bacteriophage-host interactions redirecting the bacterial metabolism to phage production. Interaction analysis of the first 16 phiKMV gene products (gp) identified homotypic interactions of gp7, gp9 and gp15. Two related yeast two-hybrid procedures, a matrix and a minilibrary approach, were applied to detect protein-protein interactions. A two-step selection procedure enabled drastic reduction of the background. Interactions were confirmed by drop tests. Multimerization of gp15 is consistent with its putative function as a DNA helicase involved in DNA replication. Homotypic interaction of gp7 and gp9 suggests they function as dimers or multimers. The absence of heterotypic interactions among early phiKMV proteins hints at their functional independence from other early phage proteins and their involvement in phage-host interactions that are important for creating optimal conditions for phage propagation. Besides, these results demonstrate the compatibility of phiKMV early gene products with the yeast two-hybrid system. Therefore, they are promising candidates to screen for interactions with host proteins.


Assuntos
Podoviridae/metabolismo , Fagos de Pseudomonas/metabolismo , Proteínas Virais/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , DNA Primase/genética , DNA Primase/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dimerização , Podoviridae/genética , Fagos de Pseudomonas/genética , Pseudomonas aeruginosa/virologia , Técnicas do Sistema de Duplo-Híbrido , Proteínas Virais/genética , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/metabolismo
18.
Arch Virol ; 152(10): 1955-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17680323

RESUMO

The proposed phiKZ genus of myoviruses has 21 members. Phages are virulent, lyse Pseudomonas bacteria, and are characterized by very large heads and correspondingly high DNA contents. The genome of the type virus, phiKZ, has 306 ORFs and over 280 kbp and is the second-largest phage genome known. The phiKZ genus has very few relationships to other phages and includes three species and one possible species.


Assuntos
Myoviridae/classificação , Myoviridae/genética , Myoviridae/patogenicidade , Fagos de Pseudomonas/classificação , Fagos de Pseudomonas/genética , Fagos de Pseudomonas/patogenicidade , Composição de Bases , Sequência de Bases , Mapeamento Cromossômico , Cromossomos , DNA Circular , DNA Intergênico , DNA Viral/análise , DNA Viral/isolamento & purificação , Genoma Viral , Temperatura Alta , Myoviridae/química , Myoviridae/isolamento & purificação , Myoviridae/ultraestrutura , Fases de Leitura Aberta , Fagos de Pseudomonas/química , Fagos de Pseudomonas/isolamento & purificação , Fagos de Pseudomonas/ultraestrutura , RNA de Transferência/genética , Proteínas Virais/análise , Vírion/química , Vírion/ultraestrutura , Virulência
19.
Cell Mol Life Sci ; 63(16): 1899-905, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16847574

RESUMO

The kinetic, thermodynamic and structural stability of gp36C, the virion-associated peptidoglycan hydrolase domain of bacteriophage phiKMV, is analyzed. Recombinant gp36C is highly thermoresistant (k = 0.595 h(-1) at 95 degrees C), but not thermostable (T(m) = 50.2 degrees C, DeltaH(cal) = 6.86 x 10(4) cal mol(-1)). However, aggregation influences kinetic stability in an unusual manner since aggregation is more pronounced at 55 degrees C than at higher temperatures. Furthermore, gp36C reversibly unfolds in a two-state endothermic transition, and circular dichroism analysis shows that gp36C almost completely refolds after a 3-h heat treatment at 85 degrees C. These properties are in agreement with gp36C being part of the extensible tail which is ejected in an unfolded state during phage infection.


Assuntos
Bacteriófagos/patogenicidade , Pseudomonas/virologia , Proteínas Virais/química , Sequência de Aminoácidos , Varredura Diferencial de Calorimetria , Dicroísmo Circular , Cinética , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Espectrofotometria , Termodinâmica , Proteínas Virais/farmacologia
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