RESUMEN
Diagnostic radiology imaging is an essential tool for adequate clinical investigation of pathological processes and the drafting of a personalized therapy plan. However, in recent years, there has been a substantial increase of requests, mainly due to technological advances but also to social and cultural reasons, not always based on the principle of the diagnostic justification. The progress of recent years in the field of diagnostic radiology has made available to the physician a variety of sophisticated radiological examinations, which are not always used rationally and appropriately. The theme is of paramount importance, particularly in childhood or adolescence, characterized by elevated radiosensitivity (high cell turnover) and longer life expectancy; therefore, children exposed to ionizing radiation are theoretically subject to a higher risk of carcinogenesis compared to the general population. For these reasons the young patients should have greater protection and examinations must respect stringent appropriateness criteria. Far from underestimating the important diagnostic and therapeutic benefits that these procedures provide, the use of ionizing radiations must minimize the radiation-related risk in accordance with the ALARA principle (As Low As Reasonably Achievable), key principle of modern radiation protection.
Asunto(s)
Dosis de Radiación , Traumatismos por Radiación/prevención & control , Protección Radiológica , Radiografía/efectos adversos , Niño , Femenino , Medicina General/normas , Medicina General/estadística & datos numéricos , Conocimientos, Actitudes y Práctica en Salud , Alfabetización en Salud , Humanos , Italia , Masculino , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/etiología , Neoplasias Inducidas por Radiación/prevención & control , Pediatría/normas , Pediatría/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Traumatismos por Radiación/etiología , Protección Radiológica/normas , Radiación Ionizante , Radiografía/normas , Radiografía/estadística & datos numéricos , Medición de Riesgo , Factores de Riesgo , Encuestas y Cuestionarios , Tomografía Computarizada por Rayos X/normasRESUMEN
Achieving high levels of quality in healthcare, which could be measurable, is increasingly important at present and is dictated by the radical changes of the welfare system imposed today by the well known economic constraints. However, even in the ongoing legislation, the practices concerning the verification and review of the quality of health care has had a major impact in the galaxy of Health. On the one hand, the citizen is developing an awareness of the possibilities of choice (Empowerment) between a plurality of providers of healthcare services, on the other hand providers themselves are obliged, within the logic of a global market, to retrain their offers to respond satisfactorily to the needs of citizens. The purpose of this study was to demonstrate how the adoption of Operational Procedures, following the granting of a certificate of accreditation to the Unit of Medical Physics, has changed the approach to the work on the part of health workers, in the direction of a dynamic quality improvement.
Asunto(s)
Hospitales Públicos/normas , Calidad de la Atención de Salud , Gestión de la Calidad Total/normas , Guías como Asunto , Humanos , Auditoría Médica , SiciliaRESUMEN
BACKGROUND: Rhinitis comprises several diseases with varying causes and different clinical manifestations and pathological features, but treated as a single clinical disorder. As heterogeneous disease, proper differential diagnosis is useful to delineate appropriate therapeutic intervention. Comparative proteomic investigation was aimed to provide information for specific differentially expressed proteins in rhino pathologic state, that could be used for diagnostic purpose and therapeutic monitoring. METHODS: Proteins extracted from nasal mucosa cells of patients with different features of rhinitis and from control subjects, were separated by 2-DE. Proteins differentially expressed were identified by mass spectrometry (MS). RESULTS: Comparative proteomic analyses led to the identification of eighteen proteins differentially expressed in patients with rhinitis, mainly related to cell defense and innate and acquired immunity. From that, at least one protein can be a possible candidate as biomarker of disease.
Asunto(s)
Mucosa Nasal/inmunología , Mucosa Nasal/patología , Rinitis/genética , Rinitis/inmunología , Adulto , Aldehído Deshidrogenasa/inmunología , Familia de Aldehído Deshidrogenasa 1 , Aldehído Deshidrogenasa Mitocondrial/inmunología , Antígenos de Neoplasias/inmunología , Biomarcadores , Electroforesis en Gel Bidimensional , Eosinófilos/patología , Femenino , Gutatión-S-Transferasa pi/inmunología , Glutatión Transferasa/inmunología , Glicoproteínas/inmunología , Subunidades de Hemoglobina/inmunología , Humanos , Isoenzimas/inmunología , Masculino , Espectrometría de Masas , Mastocitos/patología , Persona de Mediana Edad , Pólipos Nasales/inmunología , Pólipos Nasales/patología , Neutrófilos/patología , Peroxirredoxinas/inmunología , Fosfoproteínas/inmunología , Proteómica , Retinal-Deshidrogenasa , Proteínas S100/inmunología , Proteínas de Unión al Selenio/inmunología , Serpinas/inmunología , Albúmina Sérica/inmunología , Tiorredoxinas/inmunologíaRESUMEN
BACKGROUND: Treatment choice for chronic HBV infection is a continuously evolving issue, with a wide range of options. We aimed to evaluate the current practice of HBV therapies in the real world in Southern Italy. METHODS: A prospective study enrolling over a six month period (February-July 2010) all consecutive HBsAg positive subjects, never previously treated, referred to 16 liver units in two Southern Italy regions (Calabria and Sicily). RESULTS: Out of 247 subjects evaluated, 116 (46.9%) had HBV-DNA undetectable or lower than 2000 UI/ml. There were 108 (43.7%) inactive carriers, 103 (41.7%) chronic hepatitis, and 36 (14.6%) liver cirrhosis. Antiviral treatment was planned in 94 (38.0%) patients (26 cases with Interferon or Pegylated Interferon and 68 with nucleos(t)ides analogues). As many as 49.5% of subjects with chronic hepatitis did not receive antiviral treatment. DISCUSSION: The majority of chronic HBsAg carrier referring centres for evaluation were not considered suitable for antiviral treatment. Nucleos(t)ides analogues are the preferred first choice for therapy. A long-lasting period of observation may be needed to make appropriate therapeutic decisions in several cases.
Asunto(s)
Hepatitis B Crónica/tratamiento farmacológico , Adenina/análogos & derivados , Adenina/uso terapéutico , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Antivirales/uso terapéutico , Femenino , Guanina/análogos & derivados , Guanina/uso terapéutico , Antígenos e de la Hepatitis B/sangre , Humanos , Interferón-alfa/uso terapéutico , Italia , Lamivudine/uso terapéutico , Masculino , Persona de Mediana Edad , Nucleósidos/uso terapéutico , Organofosfonatos/uso terapéutico , Polietilenglicoles/uso terapéutico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Pirimidinonas/uso terapéutico , Proteínas Recombinantes/uso terapéutico , Telbivudina , Tenofovir , Timidina/análogos & derivados , Adulto JovenRESUMEN
BACKGROUND: We report the case of a patient who experienced a severe neurologic complication after treatment of diffuse large B-cell lymphoma. CASE REPORT: A 62-year old patient was diagnosed with a diffuse large B-cell lymphoma and treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone under prophylactic G-CSF substitution. After the second cycle she developed severe neurologic complications with generalized seizures and soporous condition. The MRI showed bilateral areas of signal hyperintensity in the subcortical and cortical regions in both hemispheres, consistent with the diagnosis of a reversible posterior leukoencephalopathy syndrome. The patient was under surveillance in intensive care, and a meticulous control of the blood pressure was performed. She fully recovered within a few days, and MRI changes normalized. Antineoplastic treatment had to be continued, and we chose a combination of rituximab, doxorubicin, etoposide, and prednisone. CONCLUSIONS: The reversible posterior leukoencephalopathy syndrome is believed to be the result of altered cerebral autoregulation with impaired blood flow control and resultant endothelial damage caused by different situations and agents. Several chemotherapy agents have been described in association with the syndrome. However, little is known about the prevalence of the syndrome and the follow-up of these patients, especially their further treatment.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Encefalopatías/inducido químicamente , Neoplasias del Ciego/tratamiento farmacológico , Corteza Cerebral/patología , Encefalopatía Hipertensiva/inducido químicamente , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Encefalopatías/diagnóstico , Neoplasias del Ciego/cirugía , Quimioterapia Adyuvante , Terapia Combinada , Diagnóstico Diferencial , Femenino , Humanos , Encefalopatía Hipertensiva/diagnóstico , Linfoma de Células B/cirugía , Linfoma de Células B Grandes Difuso/cirugía , Imagen por Resonancia Magnética , Persona de Mediana Edad , Remisión EspontáneaRESUMEN
BACKGROUND: To understand the molecular changes underlying Helicobacter pylori-related gastric diseases is mandatory to prevent gastric cancer. Proteomic technology is providing a rapid expansion of the basic knowledge, particularly in the discovery of new biomarkers involved in the tumourigenesis. AIM: To characterise changes in protein expression level of the gastric mucosa in H. pylori-infected patients. METHODS: The population enrolled comprised 41 dyspeptic patients. Proteins extracted from gastric mucosal specimens were analysed by 2-dimensional electrophoresis, sequenced by MALDI-TOF and identified by Edman's degradation. RESULTS: Twenty-one out of 41 patients had H. pylori infection of whom 17 had anti-CagA IgG antibodies. Several proteins were identified, of which Rho guanosine diphosphatase dissociation inhibitor alpha and heat shock protein 27 increased and glutathione transferase and antrum mucosa protein-18 decreased in H. pylori-positive in respect to H. pylori-negative patients. Interestingly, antrum mucosa protein-18, currently referred as gastrokine-1, showed two isoforms differing in the first N-terminal amino acid residue. Both gastrokine-1 isoforms were observed in the H. pylori-negative group whereas a lower expression or even absence of the gastrokine-1 basic isoform was found in a subgroup (7/21) of H. pylori-positive patients with moderate-severe gastritis. CONCLUSION: Our study demonstrated the presence of gastrokine-1 isoforms of which the basic isoform was reduced in a subset of patients with H. pylori infection.
Asunto(s)
Dispepsia/metabolismo , Endonucleasas/biosíntesis , Mucosa Gástrica/metabolismo , Infecciones por Helicobacter/metabolismo , Helicobacter pylori , Adulto , Northern Blotting , Western Blotting , Electroforesis en Gel Bidimensional , Femenino , Regulación de la Expresión Génica , Inhibidores de Disociación de Guanina Nucleótido/biosíntesis , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico/biosíntesis , Humanos , Masculino , Persona de Mediana Edad , Chaperonas Moleculares , Proteínas de Neoplasias/biosíntesis , Análisis de Secuencia por Matrices de Oligonucleótidos , Hormonas Peptídicas , Isoformas de Proteínas/biosíntesis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Inhibidores de la Disociación del Nucleótido Guanina rho-EspecíficoRESUMEN
A transient aplastic crisis (TAC) is a well-known complication in all types of chronic hemolytic anemia but only 2 cases of such an event were described in congenital dyserythropoietic anemias (CDAs). Here, we report a third case, and by retrospective chart review of 78 cases we found evidence of TAC in 8 further patients with CDA II, with serological evidence of previous human parvovirus B19 (B19V) infection in all but one. Although B19V infection results in TAC in only a minority of patients with CDA, physicians responsible for these patients should be aware of such a potentially life-threatening complication. Testing for B19V-specific IgG is recommended in patients with CDA to estimate the risk of a possible future aplastic crisis.
Asunto(s)
Anemia Diseritropoyética Congénita/complicaciones , Aplasia Pura de Células Rojas/etiología , Adolescente , Adulto , Anciano , Anticuerpos Antivirales/análisis , Niño , Preescolar , Femenino , Humanos , Persona de Mediana Edad , Infecciones por Parvoviridae/sangre , Infecciones por Parvoviridae/complicaciones , Parvovirus B19 Humano/inmunologíaRESUMEN
Done to the improvement of knowledges in hepatic surgery and postoperative care, hepatocellular carcinoma (HCC) have been treated more and more frequently by hepatic resection. Aim of this study is to report an initial series of patients affected by HCC treated by hepatic resection utilizing a new water-cooled, high-density, monopolar device, the Tissuelink Monopolar Floating Ball (Tissuelink Medical Inc., Dover, NH, U.S.A.), in order to avoid bleeding during hepatic surgery. Sex, age, kind of disease, viral and Child status, type of surgical procedure, in association to lenght of surgical procedure, blood loss, utilization of the vascular clamping of the liver, hospital stay, morbidity and mortality have been analized. Six liver resections have been performed utilizing this new device. No vascular clamping was established except one. No mortality was recorded. Morbidity was ascites in one case and pleural effusion in a second one. In conclusion the Floating Ball reduces the intraoperative bleeding during hepatic resection in patients with HCC.
Asunto(s)
Carcinoma Hepatocelular/cirugía , Técnicas Hemostáticas/instrumentación , Hepatectomía , Neoplasias Hepáticas/cirugía , Anciano , Carcinoma Hepatocelular/complicaciones , Diseño de Equipo , Femenino , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , MasculinoRESUMEN
An approach to electrical impedance tomography (EIT) data acquisition inspired by NMR-filtered back-projection imaging with fan isochromat distribution is proposed. A current projection is generated by injecting current at a certain point of the sample and simultaneously collecting the current itself at different points on the half space opposite the point of current injection. After that, the injection is shifted to another point and collected as above and so on. A very simple algebra and software support the numerical simulations. This method is expected to be more sensitive than the traditional method based on potential measurements. A preliminary low resolution experiment is presented.
Asunto(s)
Algoritmos , Simulación por Computador , Impedancia Eléctrica , Aumento de la Imagen/métodos , Pletismografía de Impedancia/métodos , Electrodos , Estudios de Factibilidad , Modelos Teóricos , Fantasmas de Imagen , Pletismografía de Impedancia/instrumentación , Dispersión de RadiaciónRESUMEN
Treatment of chronic hepatitis C is still unspecific. However, there is great expectancy concerning the new pegylated interferons. As there has been much controversy about the best parameters to determine whether treatment is effective, we analyzed several criteria currently used for evaluation, including serum alanine aminotransferase (ALT) normalization, viral load reduction and improvement of hepatic histology.
Asunto(s)
Evaluación de Medicamentos/métodos , Evaluación de Medicamentos/normas , Hepatitis C Crónica/sangre , Hepatitis C Crónica/tratamiento farmacológico , Alanina Transaminasa/sangre , Antivirales/uso terapéutico , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/virología , Humanos , Interferones/uso terapéutico , Hígado/patología , Hígado/virología , Carga ViralRESUMEN
Treatment of chronic hepatitis C is still unspecific. However, there is great expectancy concerning the new pegylated interferons. As there has been much controversy about the best parameters to determine whether treatment is effective, we analyzed several criteria currently used for evaluation, including serum alanine aminotransferase (ALT) normalization, viral load reduction and improvement of hepatic histology.
Asunto(s)
Humanos , Evaluación de Medicamentos/métodos , Evaluación de Medicamentos/normas , Hepatitis C Crónica/sangre , Hepatitis C Crónica/tratamiento farmacológico , Antivirales , Interferones , Hepacivirus , Carga Viral , Alanina Transaminasa , Hígado/patología , Hígado/virología , Hepatitis C Crónica/virologíaRESUMEN
OBJECTIVE: To evaluate the efficacy and tolerability of two different daily doses of interferon-α (lymphoblastoid-IFNα-N1, Wellferon®) [IFNα] for 2 months, followed by the same dose on alternate days for up to 1 year, versus administration on alternate days for 1 year. PATIENTS AND METHODS: A non-blind, randomised study of outpatients with chronic hepatitis C at five centres in Sicily, Italy. Ninety-seven consecutive treatment-naive patients [72 patients with hepatitis C virus (HCV) genotype 1b infection] with histological chronic hepatitis C were included in the study and randomised to receive IFNα subcutaneously: 5 million international units (MIU) daily for 2 months, followed by the same dose on alternate days for up to 1 year (n = 33, group A); 3 MIU for 2 months, followed by the same dose on alternate days for up to 1 year (32, group B); 5 MIU on alternate days for 12 months (32, group C). Adverse effects were monitored through interviews and by clinical and biochemical check-ups at 1-month intervals. RESULTS: There were no significant differences between the three groups with regard to age, gender, HCV genotype distribution, or severity of histological findings. Seven patients dropped out of the study because of severe adverse effects: three from group A, two from group B, and three from group C. Approximately 30% of the 97 patients, equally distributed between the three groups, had a 'flu-like syndrome of mild-to-moderate intensity. Dosage reduction of IFNα from 5 MIU to 3 MIU daily was necessary in two patients in group A during the first month of treatment. Overall, 88 patients completed treatment as scheduled. After the induction phase, HCV was eradicated from the bloodstream in 27 patients (81.8%) from group A versus 15 (46.9%) from group B (p < 0.001) and 15 (46.9%) from group C (p < 0.001). The switch to maintenance dosages caused some infection breakthroughs, with the result that at the end of treatment 16 patients in group A, 12 in group B and 14 in group C had undetectable serum levels of HCV-RNA. After treatment discontinuation, however, five patients in group A, four in group B and six in group C became HCV-RNA positive. Thus, at the end of follow-up, 11 patients in group A, eight in group B and eight in group C had a sustained virological response. CONCLUSION: The present study shows that induction therapy with 5 MIU of IFNα administered daily for 2 months is well tolerated and that the percentage of patients with viral eradication at the end of this phase is higher than the percentage obtained with traditional therapy. Unfortunately, this good initial response decreases as treatment continues with conventional therapy, thus nullifying the benefits of the induction phase.
RESUMEN
Although the antiviral activity of lactoferrin is one of the major biological functions of this iron binding protein, the mechanism of action is still under debate. We have investigated the role of metal binding, of sialic acid and of tryptic fragments of bovine lactoferrin (bLf) in the activity towards rotavirus (intestinal pathogen naked virus) infecting enterocyte-like cells. The antiviral activity of bLf fully saturated with manganese or zinc was slightly decreased compared to that observed for apo- or iron-saturated bLf. The antiviral activity of differently metal-saturated bLf towards rotavirus was exerted during and after the virus attachment step. The removal of sialic acid enhanced the anti-rotavirus activity of bLf. Among all the peptidic fragments obtained by tryptic digestion of bLf and characterised by advanced mass spectrometric methodologies, a large fragment (86-258) and a small peptide (324-329: YLTTLK) were able to inhibit rotavirus even if at lower extent than undigested bLf.
Asunto(s)
Antivirales/farmacología , Efecto Citopatogénico Viral/efectos de los fármacos , Lactoferrina/farmacología , Metales/química , Apoproteínas/farmacología , Electroforesis en Gel de Poliacrilamida , Células HT29 , Humanos , Lactoferrina/química , Espectrometría de Masas , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/aislamiento & purificación , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Fragmentos de Péptidos/farmacología , TripsinaRESUMEN
The chemical assessment of the complete disulphide bridge pattern in the beta-chain of human recombinant follicotropin (betaFSH) was accomplished by integrating classical biochemical methodologies with mass spectrometric procedures. A proteolytic strategy consisting of a double digestion of native betaFSH using the broad-specificity protease subtilisin first, followed by trypsin, was employed. The resulting peptide mixture was directly analysed by FAB-MS, leading to the assignment of the first three disulphide bridges. The remaining S-S bridges were determined by HPLC fractionation of the proteolytic digest followed by ESMS analysis of the individual fractions. The pattern of cysteine couplings in betaFSH was determined as: Cys3-Cys5l, Cys17-Cys66, Cys20-Cys104, Cys28-Cys82, Cys32-Cys84 and Cys87-Cys94, confirming the arrangement inferred from the crystal structure of the homologous betaCG. A subset of the S-S bridge pattern comprising Cys3-Cys51, Cys28-Cys82 and Cys32-Cys84 constitutes a cysteine knot motif similar to that found in the growth factor superfamily.
Asunto(s)
Disulfuros/química , Hormona Folículo Estimulante/química , Análisis de Secuencia de Proteína/métodos , Secuencia de Aminoácidos , Cromatografía Líquida de Alta Presión , Hormona Folículo Estimulante de Subunidad beta , Humanos , Datos de Secuencia Molecular , Proteínas Recombinantes/química , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
The mucosal lesion present in coeliac disease is an immune-mediated injury triggered by gliadin and restricted by a particular assortment of major histocompatibility complex genes. In view of this, an immunomodulatory approach that induces tolerance to this antigen appears to be a possible alternative to a strict gluten-free diet in treating coeliac disease. We have shown that intranasal administration of multiple doses of whole gliadin is required to specifically inhibit T helper 1-like T-cell reactivity in BALB/c mice immunized parenterally with whole gliadin. However, T-cell activation to multiple antigens, as a consequence of the chemical complexity shown by the antigen gliadin, could hamper efforts to identify single component(s) useful for tolerance induction. In this study, gliadin fractions were purified and administered intranasally to study their ability to induce tolerance to whole gliadin in our animal model. We found that the alpha fraction was particularly effective in downregulating both the in vitro gliadin-specific T-cell proliferation and interferon-gamma production to whole gliadin. In particular, a purified alpha-gliadin was able to suppress the immune response to the entire gliadin mixture. These results demonstrate how an immune response to a complex antigen may be controlled by treatment with a purified component and specifically indicate alpha-gliadin to be a good candidate for further identification of short peptides to be used as tolerogens in this model.
Asunto(s)
Gliadina/administración & dosificación , Gliadina/inmunología , Administración Intranasal , Animales , Enfermedad Celíaca/inmunología , Enfermedad Celíaca/terapia , Modelos Animales de Enfermedad , Femenino , Gliadina/aislamiento & purificación , Humanos , Tolerancia Inmunológica , Inmunidad Mucosa , Técnicas In Vitro , Interferón gamma/biosíntesis , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Linfocitos T/inmunologíaRESUMEN
UNLABELLED: Lamivudine and zidovudine are proving to be an important antiretroviral combination against HIV that is superior to monotherapy. Recently, with the appearance of protease inhibitors, ritonavir has been shown to be a powerful drug when used in combination with reverse transcriptase inhibitors. The objective of this study was to observe the efficacy, adverse events, and changes in the quality of life of AIDS patients receiving treatment for the first time using AZT, 3TC and ritonavir as combination therapy. We selected 36 patients diagnosed with AIDS due to opportunistic infections and evaluated them by assessing their score on quality of life scales (Karnofsky, uniscale - Quality of Life, and Quality of Life Scale), T CD(4) and CD(8) lymphocyte counts, bodyweight and symptoms during a 6 month period. Assessments were made at 2 month intervals. One patient was excluded from the trial, therefore, 35 were assessed during 6 months. RESULTS: Bodyweight increased an average of 7.2%, CD(4) increased 260 cells/mm(3) and CD(8) increased 198 cells/mm(3). The Karnofsky and uniscale QOL scales reached 100% on the fourth visit. The Quality of Life Scale showed an important increase during this study from 5.5+/-2.3 to 9.7+/-0.5. Adverse events were observed in 25.0% of the patients, most being slight. One patient had to stop taking ritonavir due to nausea and vomiting. We conclude that AZT, 3TC, and ritonavir restored the quality of life for the AIDS patients studied in terms of psychosocial aspects and overall health conditions during 6 months of treatment. The adverse events were probably related to ritonavir, but they were slight and disappeared after 2 weeks. There was a significant increase in the average number of CD(4) lymphocytes during 6 months of treatment.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida/psicología , Fármacos Anti-VIH/uso terapéutico , Calidad de Vida , Adulto , Peso Corporal , Recuento de Linfocito CD4 , Quimioterapia Combinada , Femenino , Humanos , Lamivudine/administración & dosificación , Masculino , Ritonavir/administración & dosificación , Carga Viral , Zidovudina/administración & dosificaciónRESUMEN
Two analogues of bovine beta-casomorphin-7 and beta-casomorphin-5 containing a beta-homo phenylalanine in substitution of the phenylalanine in position 3 were synthesised and tested for their mu-opioid receptor affinity. The modification enhanced the mu receptor affinity 5-fold in the case of modified beta-CM-7 and 2-fold for modified beta-CM-5 when compared to the natural peptides.
Asunto(s)
Endorfinas/metabolismo , Fenilalanina/química , Receptores Opioides mu/metabolismo , Secuencia de Aminoácidos , Animales , Bovinos , Endorfinas/química , Unión Proteica , RatasRESUMEN
The present study focused on the investigation of the chemical stability of recombinant human interferon-beta (rhIFN-beta) tested in vitro by chemical treatments that simulate stress-induced conditions that may occur during handling, storage or ageing of protein samples. Mild oxidation and/or alkylation of the recombinant protein showed that the four methionines occurring in the interferon displayed different chemical susceptibility in that Met36 and Met117 were fully modified, whereas Met1 showed only little modification and Met62 was completely resistant. Moreover, incubation of rhIFN-beta under alkaline conditions resulted in the formation of a covalent dimeric species stabilised by an intermolecular disulphide bridge involving the free SH group of Cys17 from each polypeptide chain. Analysis of biological activity of the different IFN-beta derivatives showed that rhIFN-beta fully retains its specific activity following mild oxidation treatments whereas reaction with a high concentration of alkylating agents or incubation under alkaline conditions strongly reduce its specific antiviral activity.
Asunto(s)
Interferón beta/química , Estrés Oxidativo , Antivirales/química , Antivirales/farmacología , Humanos , Interferón beta/biosíntesis , Interferón beta/farmacología , Espectrometría de Masas , Conformación Proteica , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologíaRESUMEN
Endocardiosis, a degenerative and dystrophic process affecting cardiac valves and described in many mammalian species, is characterized by the accumulation of glycosaminoglycans, in particular hyaluronic acid, in the extracellular matrix. The glycoprotein patterns of pig mitral valves in normal animals and animals affected by endocardiosis were investigated. A different N-linked glycosylation pattern of glycoproteins was detected in affected valves compared with normal ones. In either normal or pathological species, the detected N-linked glycans were of the complex type. However, in samples from affected valves, sialic acid showed a prevalence of the alpha2,6 linkage to the galactosyl residue, whereas in normal samples the most frequent linkage was of the alpha2,3 type. In normal valves, the majority of complex oligosaccharides presented two outer branches with different degrees of fucosylation and sialylation, whereas in pathological samples we noted an increased number of glycans having up to four outer branches.