RESUMEN
OBJECTIVES: Cervical cancer is the most common gynaecologic malignancy worldwide and is the sixth cause of cancer death in Chile. Human papillomavirus (HPV) is responsible for most cervical cancers. Individuals seeking basic information about HPV frequently turn to health information websites. We hypothesized that some of their data may be inaccurate. STUDY DESIGN: Comparative analysis of information. METHODS: We analyze the content of highly accessed websites such as the Spanish version of Wikipedia and Yahoo Answers through the application of a questionnaire, as well as a website managed by the Chilean Ministry of Health (Minsal). The accuracy of each answer was confirmed by comparison with information retrieved from articles published by indexed journals. RESULTS: The information provided by the Spanish version of Wikipedia was accurate; nevertheless a few omissions were detected. The quality of the information provided by the Spanish version of Yahoo Answers was inaccurate and confusing. The Minsal website lacked important information on several topics about HPV even though it is managed and endorsed by the government. CONCLUSIONS: We suggest periodical content reviews to increase the completeness, transparency and correctness of the website.
Asunto(s)
Información de Salud al Consumidor/normas , Internet/normas , Papillomaviridae , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Chile , Femenino , Humanos , Encuestas y Cuestionarios , Neoplasias del Cuello Uterino/prevención & control , Neoplasias del Cuello Uterino/virologíaRESUMEN
Six identical cDNA clones corresponding to an RNA of 1685 nucleotides that is enriched in mouse sperm compared with testis were isolated from a mouse testis cDNA library. The sequence of these clones corresponds to the 16S mitochondrial RNA plus an inverted repeat of 120 bp covalently joined to the 5' end of the RNA. By RT-PCR, it was demonstrated that this transcript, referred to as chimeric RNA, was present in mouse sperm, testis, liver, kidney, brain, and spleen. The absence of an equivalent sequence in mitochondrial DNA or as a mitochondrial pseudogene in total DNA extracted from sperm, testis, and somatic tissues suggests that the chimeric RNA is a post-transcriptional product, maybe resulting from a trans splicing reaction. The chimeric RNA was found by RT-PCR in total RNA extracted from purified sperm heads. This result was confirmed by in situ hybridization, which showed clear staining of the sperm nucleus with probes corresponding to sequences of the mitochondrial 16S RNA and the inverted repeat.
Asunto(s)
ARN/metabolismo , Espermatozoides/metabolismo , Animales , Secuencia de Bases , Quimera , ADN Complementario , Hibridación in Situ , Masculino , Ratones , Datos de Secuencia Molecular , ARN/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Mitocondrial , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
The adhesive polyphenolic proteins from Aulacomya ater and Choromytilus chorus with apparent molecular masses of 135000 and 105000, respectively, were digested with trypsin and the peptides produced resolved by reversed phase liquid chromatography. About 5 and 12 major peptides were obtained from the protein of A. ater and C. chorus, respectively. The major peptides were purified by reverse-phase chromatography and the amino acid sequence indicates that both polyphenolic proteins consisted of repeated sequence motifs in their primary structure. The major peptides of A. ater contain seven amino acids corresponding to the consensus sequence AGYGGXK, whereas the tyrosine was always found as 3, 4-dihydroxyphenylalanine (Dopa), the X residue in position 6 was either valine, leucine or isoleucine, and the carboxy terminal was either lysine or hydroxylysine. On the other hand, the major peptides of C. chorus ranged in size from 6 to 21 amino acids and the majority correspond to the consensus sequence AKPSKYPTGYKPPVK. Both proteins differ markedly in the sequence of their tryptic peptides, but they share the common characteristics of other adhesive proteins in having a tandem sequence repeat in their primary structure.
Asunto(s)
Glicina/química , Prolina/química , Proteínas/metabolismo , Secuencia de Aminoácidos , Animales , Bivalvos , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Datos de Secuencia Molecular , Mapeo Peptídico , Proteínas/química , Proteínas/aislamiento & purificación , Especificidad de la Especie , Tripsina/químicaRESUMEN
The in vitro enzymatic polymerization of the polyphenolic protein purified from the mussels Aulacomya ater, Mytilus edulis chilensis and Choromytilus chorus was studied. Mushroom tyrosinase was used to oxidize the dopa residues present in these proteins, and polymerization was monitored by acid-urea polyacrylamide gel electrophoresis. The protein from A. ater polymerized at a faster rate than the other two. Amino acid analysis of the crosslinked protein showed a notable decrease in the content of dopa, but no significant change of other amino acids. This suggests that crosslink formation may be limited to the oxidized dopa derivatives of the protein molecules.
Asunto(s)
Agaricales/enzimología , Bivalvos/metabolismo , Monofenol Monooxigenasa/química , Monofenol Monooxigenasa/metabolismo , Proteínas/química , Proteínas/metabolismo , Animales , Reactivos de Enlaces Cruzados/metabolismo , Dimerización , Especificidad por SustratoRESUMEN
A procedure for isolating the chromatoid body from the testis of 40-day-old rats was developed. Electron-microscopical analysis indicated that about 70% of the isolated organelles were chromatoid bodies, while the remaining structures corresponded to dense bodies and probably to satellites. Negative staining of the isolated organelles revealed the presence of polysome-like structures in about 20% of the chromatoid bodies suggesting that the polysomes were not due to contamination with cytoplasmic polysomes. Moreover, the presence of RNA in the stroma of the chromatoid body was confirmed by RNAse-gold staining. Preliminary electrophoretic analysis of the RNA extracted from the organelles revealed the presence of a complex population of RNAs including 5.8 and 5 S ribosomal RNAs but no tRNA.
Asunto(s)
Cromatina/ultraestructura , Polirribosomas/ultraestructura , ARN/análisis , Espermátides/ultraestructura , Animales , Masculino , ARN Ribosómico 5.8S/análisis , ARN Ribosómico 5S/análisis , Ratas , Testículo/citologíaRESUMEN
Polystyrene microtiter plates coated with 0.30 microgram/ well of the adhesive polyphenolic protein purified from the mussel Aulacomya ater showed enhanced capacity to immobilize antigens such as human chorionic gonadotrophin (hCG). Uncoated and coated wells were activated with different amounts of hCG (from 2 to 500 ng), blocked with bovine serum albumin, and tested with anti-hCG monoclonal antibodies and antimouse IgG conjugated with peroxidase. The reading at 492 nm of the uncoated wells activated with 500 ng of hCG was similar to that obtained with coated wells but using 5 to 10 ng of antigen. The coating procedure also resulted in better sensitivity to detect low concentration of monoclonal antibodies and better signal-to-noise ratio. The capacity of the mussel coating to immobilize hCG, as well as the immunoreactivity of the attached antigen, remained stable for several months.
Asunto(s)
Adhesivos , Bivalvos/química , Gonadotropina Coriónica , Animales , Anticuerpos Monoclonales , Bovinos , Humanos , InmunoensayoRESUMEN
Immunoblot analysis of sperm protein from several species revealed the presence of polypeptides recognised by anti-Sm sera obtained from patients with systemic lupus erythematosus. Immunoreactive polypeptides in human, bull, mouse and rat sperm were identified as protein B', B and D as compared with the Sm polypeptides of HeLa cells. In the sperm of rooster, the teleost fish Cyprinus carpio and the mussel Choromytilus chorus, the immunoreactive polypeptide profile was more complex. To ascertain the sperm origin of the Sm antigens, immunolocalisation with anti-Sm serum was carried out. The results demonstrated that in all the species studied staining was confined to the sperm nucleus, confirming that some polypeptides of the small nuclear ribonucleoprotein complex are present in the gamete.
Asunto(s)
Autoantígenos/análisis , Núcleo Celular/inmunología , Ribonucleoproteínas Nucleares Pequeñas/análisis , Espermatozoides/inmunología , Animales , Anticuerpos/inmunología , Western Blotting , Bovinos , Núcleo Celular/química , Pollos , Peces , Células HeLa , Humanos , Inmunohistoquímica , Lupus Eritematoso Sistémico/inmunología , Masculino , Ratones , Microscopía Electrónica , Ratas , Espermatozoides/química , Espermatozoides/ultraestructura , Proteínas Nucleares snRNPRESUMEN
Marine mussels secrete the byssus in order to attach to solid surfaces and to survive under the turbulent effects of waves. The adhesive responsible for this attachment is the polyphenolic protein secreted by the phenol gland in the foot of the animal. To purify this adhesive protein from the chilean mussel Mylilus chilensis, a modification of previous procedures has been developed. Accordingly, the protein is differentially precipitated with acetone in the presence of 0.25 N HCl. The purified protein is rich in the amino acids lysine, 3,4-dihydroxyphenylalanine, serine, threonine, proline and hydroxyproline. The protein exhibited strong adhesion to glass and other solid supports. Moreover, it has been found that the adhesive protein can mediate the immobilization of beta-galactosidase to glass. About 75% of the enzyme activity was immobilized under the experimental conditions described. This is the first study reporting the use of the polyphenolic protein to immobilize enzymes.