RESUMEN
The nonsteroidal anti-inflammatory drug (NSAID) diclofenac is highly toxic to Gyps vultures, and its recent widespread use in South Asia caused catastrophic declines in at least 3 scavenging raptors. The manufacture of veterinary formulations of diclofenac has since been banned across the region with mixed success. However, at least 12 other NSAIDs are available for veterinary use in South Asia. Aceclofenac is one of these compounds, and it is known to metabolize into diclofenac in some mammal species. The metabolic pathway of aceclofenac in cattle, the primary food of vultures in South Asia, is unknown. We gave 6 cattle the recommended dose of aceclofenac (2 mg/kg), collected blood thereafter at intervals for up to 12 h, and used liquid chromatography with mass spectrometry in a pharmacokinetic analysis of aceclofenac and diclofenac in the plasma. Nearly all the aceclofenac administered to the cattle was very rapidly metabolized into diclofenac. At 2 h, half the aceclofenac had been converted into diclofenac, and at 12 h four-fifths of the aceclofenac had been converted into diclofenac. Therefore, administering aceclofenac to livestock poses the same risk to vultures as administering diclofenac to livestock. This, coupled with the risk that aceclofenac may replace diclofenac in the veterinary market, points to the need for an immediate ban on all aceclofenac formulations that can be used to treat livestock. Without such a ban, the recovery of vultures across South Asia will not be successful.
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Antiinflamatorios no Esteroideos/toxicidad , Diclofenaco/análogos & derivados , Diclofenaco/toxicidad , Falconiformes , Animales , Asia , Bovinos , Conservación de los Recursos Naturales , Diclofenaco/metabolismo , Diclofenaco/farmacocinética , Especies en Peligro de ExtinciónRESUMEN
When planning rodent eradications, that normally involve the use of the anticoagulant poison brodifacoum, it is imperative to minimise impacts on other "non-target" species that dwell alongside the targeted rodents and may indeed be the intended beneficiaries of the eradication. Such impacts can arise either from primary poisoning when the non-target species ingest bait pellets containing toxicant or by secondary poisoning when the non-target species eats prey that has itself eaten brodifacoum. Cockroaches and woodlice, likely to scavenge bait pellets, are widely distributed on tropical and sub-tropical islands where they are eaten by ground-dwelling birds. Combining work on Henderson Island, South Pacific, site of a recent rat eradication project, and UK laboratory experiments, our study first measured brodifacoum concentrations in cockroaches given temporary ad lib access to poison bait pellets, approximately mimicking the aftermath of bait distribution for a rodent eradication. In two separate experiments using different species/exposure times, the mean brodifacoum concentrations among cockroaches immediately after bait exposure was 262±s.e. 131 and 477±168µgkg(-1) wet weight. Values decreased quickly in the following 2 weeks, and then continued to decline at a slower rate over the following 4 weeks in the more prolonged laboratory experiment. A supplementary experiment with woodlice recorded a similar brodifacoum concentration in the animals at the end of the exposure period, 223±66µgkg(-1), and a similar time course for the post-exposure decline. In the context of rails (Rallidae), a group of birds known to be particularly susceptible to primary brodifacoum poisoning, these results suggested that, in terms of acute exposure, individual birds would need to eat a minimum of their own body weight (and more commonly 2-5 times that) of live cockroaches before facing a 50% risk of death. Therefore, we conclude that in eradication scenarios, acute secondary poisoning is of lower concern for these birds than primary poisoning.
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4-Hidroxicumarinas/análisis , Cucarachas/química , Isópodos/química , Rodenticidas/análisis , Análisis de Varianza , Animales , Islas , Factores de TiempoRESUMEN
BACKGROUND: The biological mechanisms that contribute to atrophic long bone non-union are poorly understood. Multipotential mesenchymal stromal cells (MSCs) are key contributors to bone formation and are recognised as important mediators of blood vessel formation. This study examines the role of MSCs in tissue formation at the site of atrophic non-union. MATERIALS AND METHODS: Tissue and MSCs from non-union sites (n = 20) and induced periosteal (IP) membrane formed following the Masquelet bone reconstruction technique (n = 15) or bone marrow (n = 8) were compared. MSC content, differentiation, and influence on angiogenesis were measured in vitro. Cell content and vasculature measurements were performed by flow cytometry and histology, and gene expression was measured by quantitative polymerase chain reaction (qPCR). RESULTS: MSCs from non-union sites had comparable differentiation potential to bone marrow MSCs. Compared with induced periosteum, non-union tissue contained similar proportion of colony-forming cells, but a greater proportion of pericytes (p = 0.036), and endothelial cells (p = 0.016) and blood vessels were more numerous (p = 0.001) with smaller luminal diameter (p = 0.046). MSCs showed marked differences in angiogenic transcripts depending on the source, and those from induced periosteum, but not non-union tissue, inhibited early stages of in vitro angiogenesis. CONCLUSIONS: In vitro, non-union site derived MSCs have no impairment of differentiation capacity, but they differ from IP-derived MSCs in mediating angiogenesis. Local MSCs may thus be strongly implicated in the formation of the immature vascular network at the non-union site. Attention should be given to their angiogenic support profile when selecting MSCs for regenerative therapy.
RESUMEN
INTRODUCTION: To investigate the prevalence of calreticulin (CALR) mutations in JAK2- and MPL-non-mutated patients with suspected myeloproliferative neoplasm (MPN) from a large MPN clinic and confirm a diagnosis of MPN. METHODS: JAK2/MPL-non-mutated patients from the Belfast City Hospital (BCH) with either of the MPNs - ET or MF - and diagnosed between 1988 and 2014 were selected for CALR screen. All cases were validated according to the WHO 2008 classification for MPNs. Statistical analysis was performed with Minitab 16 Statistical Software package. Exon 9 of CALR was amplified by PCR using genomic DNA, and mutations were detected by fragment analysis. RESULTS: Of the 62 JAK2/MPL-non-mutated MPN patients screened, 57 had ET and 5 had MF; 34 patients (53.1%) carried CALR mutations. Three of 5 MF patients were CALR positive. Thirty-one ET patients (54.3%) harboured CALR mutation, whereas 26 (45.7%) were classified as 'triple negatives'. CONCLUSION: Detection of CALR mutations in a cohort of JAK2/MPL-non-mutated patients with suspected MPN confirmed the diagnosis of MPN in around 53% of cases. This is lower than initially reported, but similar to subsequent studies. However, a sizable cohort of patients remains lacking a specific molecular marker.
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Calreticulina/genética , Trastornos Mieloproliferativos/diagnóstico , Trastornos Mieloproliferativos/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Janus Quinasa 2/genética , Masculino , Persona de Mediana Edad , Mutación , Trastornos Mieloproliferativos/mortalidad , Prevalencia , Pronóstico , Receptores de Trombopoyetina/genéticaRESUMEN
ALK-positive diffuse large B-cell lymphoma is a rare, recently characterized lymphoma subtype that shows granular cytoplasmic ALK expression. This report describes a primary gastric ALK-positive B-lineage lymphoma in which a clathrin (CLTC)-ALK fusion was identified by RT-PCR and direct sequencing of the breakpoint. This confirmed the presence of t(2;17)(p23;q23) involving the CLTC gene and is only the 4th report of such a translocation in this lymphoma subtype and the first to describe this tumor within the stomach. As in previous reports, immunophenotyping showed the malignant cell to be a terminally differentiated B-lineage cell characterized by the absence of B-cell antigens and expression of antigens associated with plasma cell differentiation. This case confirms the existence of such a lymphoma subtype arising in extranodal locations and underscores the importance of detailed immunophenotyping and specialized molecular genetic investigations in confirming the diagnosis.
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Clatrina/genética , Linfoma de Células B/genética , Linfoma de Células B Grandes Difuso/genética , Proteínas Tirosina Quinasas/genética , Neoplasias Gástricas/genética , Adulto , Quinasa de Linfoma Anaplásico , Secuencia de Bases , Humanos , Masculino , Datos de Secuencia Molecular , Proteínas Tirosina Quinasas Receptoras , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Translocación GenéticaRESUMEN
Fourteen patients with corticosteroid-resistant acute GVHD were treated with a murine monoclonal antibody to the pp55 interleukin-2 (IL-2) receptor (MoAb BT 563). Nine of the 14 patients had also failed Xoma-Zyme-H65 as GVHD prophylaxis and/or treatment. Seven patients had received HLA-matched sibling donor bone marrow transplants, five had received HLA-matched transplants from unrelated volunteer donors, and two had received one-antigen mismatched transplants from unrelated volunteer donors. At the time of MoAb BT 563 therapy, the overall clinical grading of acute GVHD (Seattle grading system) was as follows: grade II--one patient, grade III--four patients, and grade IV--nine patients. MoAb BT 563 was administered as a short iv infusion of 5 mg daily for 10 doses, followed by 5 mg on alternate days for a further five doses. A complete response (CR) was observed in four patients (28%), and a partial response (PR) in four patients (28%). All four complete responders were treated within 28 days of first onset of grade > or = II acute GVHD. Four patients (three CR, one PR) remain alive. One complete responder subsequently died from chronic GVHD. MoAb BT 563 administration was well tolerated in all 14 patients; no significant toxicity was observed. We conclude that MoAb BT 563 directed against the IL-2 receptor on activated T lymphocytes may be useful in treating corticosteroid-resistant acute GVHD if given early, but that it is of limited value in attempting to rescue patients with far-advanced refractory acute GVHD.(ABSTRACT TRUNCATED AT 250 WORDS)
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Corticoesteroides/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Trasplante de Médula Ósea , Enfermedad Injerto contra Huésped/prevención & control , Receptores de Interleucina-2/inmunología , Adulto , Relación Dosis-Respuesta a Droga , Resistencia a Medicamentos , Femenino , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tasa de SupervivenciaRESUMEN
The clinical effects of cyclosporin were evaluated during cytotoxic treatment in a 61 year old man with acute myeloid leukaemia. He had required a renal transplant 18 months before presenting with acute myeloid leukaemia (FAB subtype M4). He had received cyclosporin 3.5-4.0 mg/kg daily to maintain a plasma cyclosporin concentration of 75-150 ng/ml. Cyclosporin was continued during induction chemotherapy with daunorubicin, cytarabine, and 6-thioguanine (DAT). He had fever and oropharyngeal candidiasis that was unresponsive to anti-bacterial drugs but responsive to systemic amphotericin. Bone marrow examination 14 days after chemotherapy showed complete haematological remission. Subsequently he tolerated consolidation treatment with DAT with no serious complications. Unfortunately he developed fatal septicaemia following a second consolidation with mitozantrone and cytarabine. Inhibition of P-glycoprotein activity by cyclosporin may not significantly increase the toxicity of aggressive chemotherapeutic regimens, and as benefit may be achieved by this approach further clinical evaluation is justified.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclosporinas/uso terapéutico , Trasplante de Riñón , Leucemia Mielomonocítica Aguda/tratamiento farmacológico , Complicaciones Posoperatorias/tratamiento farmacológico , Citarabina/administración & dosificación , Daunorrubicina/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Tioguanina/administración & dosificaciónRESUMEN
AIMS: To investigate the incidence of functional hyposplenism in a group of patients who had undergone allogeneic bone marrow transplantation (BMT). METHODS: Splenic function was assessed by counting the number of gluteraldehyde fixed red blood cells containing pits or indentations as examined by interference phase microscopy. Normal values are < 2% whereas splenectomy patients have values of 25 to 40%. RESULTS: Twenty eight BMT recipients (17 men, 11 women) were studied at varying periods post-transplant and the results compared with 20 healthy volunteers and 10 patients who had undergone splenectomy or had splenic atrophy because of haematological conditions. Of the 28 BMT recipients, one had undergone a prior splenectomy; of the remaining 27 patients, four (15%) had evidence of functional hyposplenism with between 5.0 and 34.0% pitted cells. Of these four patients, one had active extensive chronic graft versus host disease (GvHD) which has been previously reported to be associated with functional hyposplenism following transplantation. Only one of the four patients had peripheral blood red cell changes typical of hyposplenism. CONCLUSION: These results confirm that extensive chronic GvHD is associated with hyposplenism. Intermediate degrees of functional hyposplenism may also occur following BMT in the absence of chronic GvHD and in the absence of haematological features of hyposplenism on routine blood films. This may be of significance in mediating the susceptibility to infection with encapsulating bacteria seen following allogeneic BMT.
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Trasplante de Médula Ósea/efectos adversos , Enfermedad Injerto contra Huésped/complicaciones , Bazo/fisiopatología , Enfermedades del Bazo/complicaciones , Adolescente , Adulto , Anciano , Trasplante de Médula Ósea/fisiología , Niño , Enfermedad Crónica , Estudios Transversales , Eritrocitos/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Esplenectomía , Enfermedades del Bazo/sangre , Trasplante HomólogoRESUMEN
Determination of the biologic potential of lymphoid proliferations in biopsies can be difficult by standard histological or even immunohistochemical examination. Polymerase chain reaction (PCR) has been used with increasing frequency to detect clonal rearrangements of the immunoglobulin heavy chain (IgH) in formaldehyde fixed, paraffin wax embedded tissues. Sensitivity ranges between 50 and 80%, and therefore at least 20% of neoplasms remain undetected by these approaches. Few investigators have attempted to detect immunoglobulin light chain (IgL) gene rearrangements by PCR using paraffin wax embedded samples. We studied 29 cases of B-cell neoplasms, along with 21 cases with equivocal histology and 4 reactive biopsies, using degenerate oligoprimers to amplify Ig(kappa) and Ig(lambda) light chain genes, along with IgH (Fr 1, 2 and 3) gene rearrangement analysis. The combination of these methods detected clonality in 93% of cases (27/29) with histological diagnosis of B-NHL. Fr2 and Fr3 primers detected clonality in 79% (23/29) of cases. IgL chain rearrangements detected 4 cases (14%), negative for IgH rearrangements, improving sensitivity from 79 to 93%. Clonality was detected in 52% (11/21) of histologically equivocal lymphoid proliferations, including one case detected by IgL rearrangements which was negative for IgH rearrangements. Archival material from 4 cases with reactive histology produced polyclonal results. These results confirm that PCR based immunoglobulin gene rearrangement is a sensitive and specific method for demonstrating B-cell clonality in paraffin-wax embedded sections. The addition of IgL analysis to the IgH assay allows the detection of greater than 90% of B-cell lymphoproliferative disorders from routine histological specimens with poor preservation of genomic DNA.
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Formaldehído/farmacología , Reordenamiento Génico , Inmunoglobulinas/genética , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B/genética , Biopsia , Línea Celular Tumoral , Humanos , Inmunohistoquímica , Reacción en Cadena de la Polimerasa , Rayos UltravioletaRESUMEN
OBJECTIVE: To identify measures of immune state that reflect the course of HIV related disease in order to predict deterioration of symptoms and assess response to treatment. DESIGN: Five year longitudinal clinical and laboratory study. SETTING: Regional haemophilia centre, university virology laboratory, and Medical Research Council laboratory. PATIENTS: 32 Patients with haemophilia A exposed to a single batch of HIV contaminated factor VIII concentrate from the Scottish National Blood Transfusion Service in 1984 who were followed up regularly in Edinburgh (31) or abroad (one). MAIN OUTCOME MEASURES: Counts of circulating T cell subsets (CD4 and CD8); plasma beta 2 microglobulin, neopterin, and IgA concentrations; and delayed type hypersensitivity to multiple skin test antigens. RESULTS: 18 Patients who seroconverted after exposure had received significantly more contaminated factor VIII than the 14 who did not (mean 43 (range 9-109) v 15 (3-30) phials, p less than 0.01). The two groups were not distinguishable by other criteria before exposure. The group that seroconverted subsequently showed a progressive fall in mean circulating CD4 lymphocytes and an increase in plasma beta 2 microglobulin and neopterin concentrations. From 1987 patients in this group also showed an increase in mean circulating CD8 lymphocytes and in plasma IgA concentration, neither of which was seen in patients who did not seroconvert. Patients with HIV antibody who developed Centers for Disease Control category IV symptoms within five years after infection showed more extreme changes in all measures, except CD8 lymphocyte count, than those whose symptoms remained in categories II and III. Skin test reactivity declined to barely detectable levels in all patients positive for HIV antibody. CONCLUSIONS: Serial estimates of circulating CD4 lymphocytes and of plasma beta 2 microglobulin concentration are the most reliable measures of disease progression; of these, beta 2 microglobulin concentration seems to be the better predictor of impending serious symptoms. High IgA concentrations reflect rather than predict disease state. Individual variation in most measures is such that a wide range of measurements should be used in assessing the effects of trial treatment in HIV infected patients without symptoms.
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Infecciones por VIH/inmunología , Hemofilia A/inmunología , Adolescente , Adulto , Biopterinas/análogos & derivados , Biopterinas/sangre , Linfocitos T CD4-Positivos , Infecciones por VIH/etiología , Seropositividad para VIH/inmunología , Humanos , Inmunoglobulina A/análisis , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Neopterin , Estudios Prospectivos , Escocia , Linfocitos T Reguladores , Microglobulina beta-2/metabolismoRESUMEN
Circulating antigliadin antibody has been described in patients with gluten enteropathy although the prevalence varies in different studies. It has been suggested that the investigation for antigliadin antibody might be useful as a screening test. The object of the present study was to evaluate two different techniques for assaying these antibodies - an indirect immunofluorescent method and an enzyme-linked immunosorbent assay (ELISA). Antibodies were assayed in the sera of 102 patients in whom jejunal biopsies were also obtained. The specificity of both tests was greater than 95%, and the correlation between the presence of antibody and histology was significant (p < 0.005), though the sensitivity of each test was less than 70%.
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Anticuerpos/análisis , Enfermedad Celíaca/inmunología , Gliadina/inmunología , Proteínas de Plantas/inmunología , Adolescente , Adulto , Anciano , Enfermedad Celíaca/patología , Femenino , Humanos , Yeyuno/patología , Masculino , Persona de Mediana EdadAsunto(s)
Linfoma no Hodgkin/tratamiento farmacológico , Metotrexato/efectos adversos , Síndrome de Stevens-Johnson/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bleomicina/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Humanos , Leucovorina/administración & dosificación , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Prednisolona/administración & dosificación , Prednisona/administración & dosificación , Inducción de Remisión , Vincristina/administración & dosificaciónRESUMEN
CD74 (major histocompatibility complex (MHC) Class II invariant chain) has recently been identified as the cell-surface receptor for the pro-tumorigenic cytokine macrophage migration inhibitory factor (MIF). Therefore, we investigated CD74 gene expression in intestinal adenomas in Apc(Min/+) mice and humans. CD74 mRNA (p31 and p41 splice variants) and immunoreactive CD74 protein levels were significantly lower in small intestinal and colonic Apc(Min/+) mouse adenomas compared with histologically normal mucosa. These findings were mirrored by a reduction in MHC Class II expression and Class II trans-activator type IV transcripts. Conversely, CD74 protein levels were actually increased in dysplastic epithelial cells in 47/55 (85%) human colorectal adenomas, with CD74 and MIF protein levels together predicting increasing dysplasia in individual adenomas (P=0.003). Down-regulation of CD74 during Apc(Min/+) mouse intestinal tumorigenesis does not model increased CD74 expression at the early, benign stages of human colorectal carcinogenesis. Epithelial cell CD74 represents a valid target for anti-CRC therapy.
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Adenoma/inmunología , Antígenos de Diferenciación de Linfocitos B/metabolismo , Antígenos de Neoplasias/metabolismo , Neoplasias Colorrectales/inmunología , Antígenos de Histocompatibilidad Clase II/metabolismo , Animales , Antígenos de Diferenciación de Linfocitos B/genética , Antígenos de Neoplasias/genética , Regulación hacia Abajo/inmunología , Regulación Neoplásica de la Expresión Génica/inmunología , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , ARN Mensajero/genética , ARN Neoplásico/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Transactivadores/metabolismoRESUMEN
This report describes a case of aleukaemic myeloid sarcoma of the small intestine in a 50-year-old woman presenting with small bowel obstruction. Fluorescence in situ hybridisation analysis of interphase nuclei revealed a split CBFbeta signal, consistent with an underlying inversion of chromosome 16, inv(16)(p13q22). The resultant type A CBFbeta/MYH11 transcript was detected by reverse transcriptase PCR. Immunohistochemistry with the AH107 antibody to the CBFbeta-SMMHC chimeric protein showed strong nuclear staining of the tumour cell nuclei. This represents the first use of this antibody in the diagnosis of this subtype of myeloid sarcoma in the small intestine.
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Inversión Cromosómica , Cromosomas Humanos Par 16/genética , Neoplasias del Íleon/genética , Proteínas de Fusión Oncogénica/metabolismo , Sarcoma Mieloide/genética , Femenino , Humanos , Neoplasias del Íleon/metabolismo , Neoplasias del Íleon/patología , Hibridación Fluorescente in Situ/métodos , Persona de Mediana Edad , Proteínas de Neoplasias/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Sarcoma Mieloide/metabolismo , Sarcoma Mieloide/patologíaRESUMEN
Advanced age is an indicator of poor prognosis in chronic myeloid leukaemia (CML). Since obtaining its UK licence in 2001, the tyrosine kinase inhibitor imatinib mesylate has effected a paradigm shift in the treatment of CML. We compared survival and molecular response rates in elderly patients to younger patients presenting with CML since the introduction of imatinib. Twenty-five patients aged >60 years were identified. No significant survival difference was found when this group was compared with younger patients. In the elderly group, 53% of those with molecular data (36% of all elderly patients) had a major molecular response as assessed by real time quantitative PCR (RT-PCR). The advent of imatinib therapy appears to have ameliorated much of the negative impact of advancing age on survival in patients with CML.
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Antineoplásicos/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Adulto , Anciano , Benzamidas , Ensayos Clínicos Fase I como Asunto , Humanos , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/mortalidad , Irlanda del Norte , Pronóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de SupervivenciaRESUMEN
Interleukin (IL)-4 receptor (IL-4R) alpha chain-dependent signalling by IL-4 and IL-13 promotes tumour growth and metastasis in mouse models of colorectal cancer. However, the role of IL-4R alpha-dependent signalling during the early, pre-malignant stages of colorectal carcinogenesis has not been investigated. Therefore, we investigated the effect of deletion of the IL-4R alpha gene on azoxymethane-induced colorectal aberrant crypt focus (ACF) multiplicity and size in Balb/c mice. IL-4R alpha(-/-) mice developed significantly more ACFs [median 8, inter-quartile range (IQR) 4-11.5; n = 9] than wild-type (WT) animals (median 4, IQR 1-6; n = 9; p = 0.04, Mann-Whitney U-test). There were significantly higher levels of IL-4 in serum from azoxymethane- and sham-treated IL-4R alpha(-/-) mice than WT animals, but no difference in serum IL-13 levels. In the absence of functional IL-4Rs, IL-13 can also signal via the IL-13R alpha2 receptor, leading to induction of transforming growth factor (TGF) beta, which has pro-tumourigenic activity at early stages of intestinal tumourigenesis. We found that mucosal TGFbeta mRNA levels and intestinal epithelial cell TGFbeta immunoreactivity were significantly higher in IL-4R alpha(-/-) mice than in WT animals. In summary, IL-4R alpha-dependent signalling has a protective, anti-neoplastic role during the post-initiation phase of azoxymethane-induced colorectal carcinogenesis in Balb/c mice. Our data should prompt thorough investigation of the role of IL-4R alpha-dependent signalling during human colorectal carcinogenesis, particularly as antagonism of IL-4R signalling represents a therapeutic strategy for asthma and other allergic diseases.
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Neoplasias Colorrectales/inmunología , Lesiones Precancerosas/inmunología , Receptores de Superficie Celular/inmunología , Animales , Azoximetano , Carcinógenos , Transformación Celular Neoplásica/inmunología , Transformación Celular Neoplásica/patología , Neoplasias Colorrectales/inducido químicamente , Neoplasias Colorrectales/patología , Modelos Animales de Enfermedad , Femenino , Interleucina-13/sangre , Interleucina-4/sangre , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/patología , Receptores de Superficie Celular/deficiencia , Transducción de Señal/inmunología , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Necrosis Tumoral alfa/sangreRESUMEN
The taxonomic status of populations of rockhopper penguins (Eudyptes chrysocome) is still enigmatic. Northern populations differ from southern ones in breeding phenology, song characteristics and head ornaments used as mating signals. We conducted a molecular analysis using mitochondrial DNA sequencing to test if there is a gene flow barrier between northern (subtropical) populations and southern (subantarctic) populations in relation to the Subtropical Convergence, a major ecological boundary for marine organisms. Sequences of the control region and the ND2 gene were analysed in rockhopper penguins and in the macaroni penguin (Eudyptes chrysolophus), a closely related species. Genetic distances and phylogenetic analyses showed a clear split into three clades, two rockhopper clades and the macaroni penguin. Moreover, Theta(ST) and gene flow estimates also suggested genetic structuring within the northern rockhoppers. Our results add further support to the notion that the two rockhopper penguin taxa, often considered as two subspecies, can be recognized as two species E. chrysocome and E. moseleyi. The divergence in mating signals found between these two taxa seems to have occurred recently and relatively rapidly. Thus, the behavioural changes may have been enough to isolate these taxa without the need for morphological differentiation. The findings have important conservational implications, since E. moseleyi is far less abundant than E. chrysocome, but more populations may warrant an uplisting to endangered status if full species status should be recognized for more subpopulations.