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1.
Blood Cancer J ; 11(7): 136, 2021 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-34330895

RESUMEN

B-cell chronic lymphocytic leukaemia (CLL) is associated with immunosuppression and patients are at increased clinical risk following SARS-CoV-2 infection. Covid-19 vaccines offer the potential for protection against severe infection but relatively little is known regarding the profile of the antibody response following first or second vaccination. We studied spike-specific antibody responses following first and/or second Covid-19 vaccination in 299 patients with CLL compared with healthy donors. 286 patients underwent extended interval (10-12 week) vaccination. 154 patients received the BNT162b2 mRNA vaccine and 145 patients received ChAdOx1. Blood samples were taken either by venepuncture or as dried blood spots on filter paper. Spike-specific antibody responses were detectable in 34% of patients with CLL after one vaccine (n = 267) compared to 94% in healthy donors with antibody titres 104-fold lower in the patient group. Antibody responses increased to 75% after second vaccine (n = 55), compared to 100% in healthy donors, although titres remained lower. Multivariate analysis showed that current treatment with BTK inhibitors or IgA deficiency were independently associated with failure to generate an antibody response after the second vaccine. This work supports the need for optimisation of vaccination strategy in patients with CLL including the potential utility of booster vaccines.


Asunto(s)
Anticuerpos Antivirales , Formación de Anticuerpos/efectos de los fármacos , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , Leucemia Linfocítica Crónica de Células B , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Vacuna BNT162 , COVID-19/sangre , COVID-19/inmunología , COVID-19/prevención & control , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/inmunología , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/sangre , Leucemia Linfocítica Crónica de Células B/inmunología , Masculino , Persona de Mediana Edad
3.
BJOG ; 126(8): 1025-1031, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30811810

RESUMEN

OBJECTIVE: Pregnancies in women with Loeys-Dietz syndrome (LDS) are rare and are typically documented in case reports only. Early reports suggested high rates of maternal complications during pregnancy and the puerperium, including aortic dissection and uterine rupture, but information on fetal outcomes was very limited. DESIGN: A retrospective cohort study. SETTING: Eight specialist UK centres. SAMPLE: Pregnant women with LDS. METHODS: Data was collated on cardiac, obstetric, and neonatal outcomes. MAIN OUTCOME MEASURES: Maternal and perinatal outcomes in pregnancies complicated by LDS. RESULTS: Twenty pregnancies in 13 women with LDS were identified. There was one miscarriage, one termination of pregnancy, and 18 livebirths. In eight women the diagnosis was known prior to pregnancy but only one woman had preconception counselling. In four women the diagnosis was made during pregnancy through positive genotyping, and the other was diagnosed following delivery. Five women had a family history of aortic dissection. There were no aortic dissections in our cohort during pregnancy or postpartum. Obstetric complications were common, including postpartum haemorrhage (33%) and preterm delivery (50%). In all, 14/18 (78%) of deliveries were by elective caesarean section, at a median gestational age at delivery of 37 weeks. Over half the infants (56%) were admitted to the neonatal unit following delivery. CONCLUSION: Women with LDS require multidisciplinary specialist management throughout pregnancy. Women should be referred for preconception counselling to make informed decisions around pregnancy risk and outcomes. Early elective preterm delivery needs to be balanced against a high infant admission rate to the neonatal unit. TWEETABLE ABSTRACT: Pregnancy outcomes in women with Loeys-Dietz syndrome.


Asunto(s)
Síndrome de Loeys-Dietz/complicaciones , Complicaciones del Embarazo/etiología , Resultado del Embarazo , Adulto , Parto Obstétrico/métodos , Femenino , Humanos , Recién Nacido , Hemorragia Posparto/etiología , Embarazo , Nacimiento Prematuro/etiología , Estudios Retrospectivos , Factores de Riesgo , Reino Unido/epidemiología
4.
Leukemia ; 30(1): 65-73, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26202928

RESUMEN

Metabolic transformation in cancer is increasingly well understood. However, little is known about the metabolic responses of cancer cells that permit their survival in different microenvironments. We have used a nuclear magnetic resonance based approach to monitor metabolism in living primary chronic lymphoid leukemia (CLL) cells and to interrogate their real-time metabolic responses to hypoxia. Our studies demonstrate considerable metabolic plasticity in CLL cells. Despite being in oxygenated blood, circulating CLL cells are primed for hypoxia as measured by constitutively low level hypoxia-inducible factor (HIF-1α) activity and modest lactate production from glycolysis. Upon entry to hypoxia we observed rapid upregulation of metabolic rates. CLL cells that had adapted to hypoxia returned to the 'primed' state when re-oxygenated and again showed the same adaptive response upon secondary exposure to hypoxia. We also observed HIF-1α independent differential utilization of pyruvate in oxygenated and hypoxic conditions. When oxygenated, CLL cells released pyruvate, but in hypoxia imported pyruvate to protect against hypoxia-associated oxidative stress. Finally, we identified a marked association of slower resting glucose and glutamine consumption, and lower alanine and lactate production with Binet A0 stage samples indicating that CLL may be divided into tumors with higher and lower metabolic states that reflect disease stage.


Asunto(s)
Adaptación Fisiológica , Leucemia Linfocítica Crónica de Células B/metabolismo , Puntos de Control del Ciclo Celular , Hipoxia de la Célula , Ciclo del Ácido Cítrico , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/análisis , Espectroscopía de Resonancia Magnética , Ácido Pirúvico/farmacología
5.
BMJ Case Rep ; 20152015 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-26531741

RESUMEN

Our patient is an 18-year-old Caucasian woman from the UK who developed severe mitral stenosis on a history of childhood acute rheumatic fever (ARF) and rheumatic heart disease (RHD). She had been reporting of her oral penicillin secondary prophylaxis regimen since diagnosis. At the age of 15 years, a new murmur was discovered during routine cardiac follow-up. An echocardiogram confirmed moderate-severe mitral stenosis. One year later, her exercise tolerance significantly deteriorated and she subsequently underwent balloon valvuloplasty of her mitral valve to good effect. Our case emphasises the evidence base supporting the use of monthly intramuscular penicillin injection to prevent ARF recurrence and RHD progression; it also emphasises the reduced efficacy of oral penicillin prophylaxis in this context. It particularly resonates with regions of low rheumatic fever endemicity. The long-term cardiac sequelae of ARF can be devastating; prescribing the most effective secondary prophylaxis regimen is essential.


Asunto(s)
Antibacterianos/administración & dosificación , Estenosis de la Válvula Mitral/prevención & control , Penicilinas/administración & dosificación , Fiebre Reumática/complicaciones , Cardiopatía Reumática/prevención & control , Administración Oral , Adolescente , Progresión de la Enfermedad , Femenino , Humanos , Estenosis de la Válvula Mitral/microbiología , Cardiopatía Reumática/microbiología , Insuficiencia del Tratamiento , Reino Unido
7.
QJM ; 108(10): 789-94, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25638788

RESUMEN

BACKGROUND: Chronic lymphocytic leukaemia (CLL) is the commonest leukaemia in western society. Most patients are detected incidentally at an early stage and require 'watch and wait' follow-up. In the UK, management of Stage A0 CLL varies with some centres advising regular outpatient haematology follow-up, whereas others recommend management within primary care. The safety and effectiveness of these two management options are currently unknown. METHODS: An observational retrospective cohort study in outpatient Haematology clinics at Queen Elizabeth Hospital Birmingham (QEH) and Birmingham Heartlands Hospital (BHH) and primary care practices in West Midlands, UK. All patients diagnosed with stable stage A0 CLL since 2002 at BHH or QEH were identified. At BHH, patients were discharged to primary care follow-up, whilst QEH patients remained under haematology for follow-up. Evidence of disease progression, need for treatment and overall mortality was documented. RESULTS: Two hundred and forty-six Stage A0 CLL patients were identified. One hundred and five (43%) patients were discharged to primary care, whilst 141 (57%) patients were followed up in haematology outpatient clinics. No difference in mortality or need for treatment was found between the two groups. Of those discharged, 93 (66%) remained in primary care. CONCLUSION: The management of stable-stage A0 CLL within primary or secondary care leads to equivalent clinical outcomes. The prevalence of early-stage CLL is expected to increase with the ageing population and management within primary care should be considered as a potentially effective approach.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/mortalidad , Leucemia Linfocítica Crónica de Células B/terapia , Atención Primaria de Salud/organización & administración , Tiempo de Tratamiento/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Manejo de la Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pacientes Ambulatorios , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
8.
Adv Chronic Kidney Dis ; 19(5): 291-6, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22920639

RESUMEN

Screening for a monoclonal protein is a common part of the assessment of patients presenting with a renal injury. While in the settings of acute kidney injury, chronic kidney disease and proteinuria monoclonal proteins can be associated with significant pathologies such as cast nephropathy, amyloidosis, and light chain deposition disease, they can also be an unrelated finding. The purpose of this review is to provide the nephrologist with an update to the diagnostic assessment and risk stratification of monoclonal proteins to avoid unnecessary investigation and monitoring of those patients with low-risk monoclonal gammopathies.


Asunto(s)
Inmunoglobulinas/sangre , Gammopatía Monoclonal de Relevancia Indeterminada/diagnóstico , Lesiones Precancerosas/diagnóstico , Progresión de la Enfermedad , Humanos , Cadenas Ligeras de Inmunoglobulina/sangre , Cadenas Ligeras de Inmunoglobulina/orina , Gammopatía Monoclonal de Relevancia Indeterminada/sangre , Gammopatía Monoclonal de Relevancia Indeterminada/orina , Lesiones Precancerosas/sangre , Lesiones Precancerosas/orina , Medición de Riesgo
9.
J Hosp Infect ; 78(4): 302-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21481491

RESUMEN

West Midlands was particularly affected by the 2009 H1N1 influenza A (pH1N1) pandemic. Vaccination of frontline healthcare professionals (HCPs) aimed to prevent spread to vulnerable patients, minimise service disruption and protect staff. HCPs involved in upper airway management are particularly at risk of aerosol exposure. We assessed the attitudes of these HCPs towards pandemic influenza A (H1N1) 2009 vaccination uptake: primary reasons for acceptance, barriers to vaccination, and knowledge surrounding pH1N1 influenza. We performed a voluntary, anonymous questionnaire survey based in two West Midlands National Health Service Trusts, one month after introduction of the vaccine. In all, 187 useable responses were received (60.5% response rate); 43.8% (N=82) had/intended to receive vaccination. Concern over long term side-effects was the main deterrent (37.4%, N=70). Primary reasons for potentially accepting vaccination were: to protect themselves (36.9%, N=69), to protect family (35.3%, N=66), and to protect patients (10.2%, N=19). Of responders, 76.5% were unsure that the vaccines had undergone suitably rigorous clinical trials to ensure safety; 20.9% correctly identified reported vaccine efficacy. We conclude that pH1N1 vaccination uptake among high risk HCPs remained low, although twice that of peak seasonal influenza vaccination rates. HCPs' knowledge of vaccine efficacy is poor. Barriers to vaccination include concerns over safety profile given the short chronological time-span between the pandemic being declared and vaccine introduction. Side-effects, both acute and chronic, are a significant barrier to vaccination. Further reassurance/education surrounding vaccine safety/efficacy at the time of any future pandemic may improve uptake rates.


Asunto(s)
Actitud del Personal de Salud , Infección Hospitalaria/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/prevención & control , Vacunación/estadística & datos numéricos , Cuidados Críticos , Infección Hospitalaria/transmisión , Infección Hospitalaria/virología , Transmisión de Enfermedad Infecciosa/prevención & control , Hospitales , Humanos , Gripe Humana/transmisión , Gripe Humana/virología , Encuestas y Cuestionarios
10.
Fish Shellfish Immunol ; 30(6): 1209-22, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21463691

RESUMEN

The inception of ecological immunology has led to an increase in the number of studies investigating the impact of environmental stressors on host immune defence mechanisms. This in turn has led to an increased understanding of the importance of invertebrate groups for immunological research. This review discusses the advances made within marine invertebrate ecological immunology over the past decade. By demonstrating the environmental stressors tested, the immune parameters typically investigated, and the species that have received the greatest level of investigation, this review provides a critical assessment of the field of marine invertebrate ecological immunology. In highlighting the methodologies employed within this field, our current inability to understand the true ecological significance of any immune dysfunction caused by environmental stressors is outlined. Additionally, a number of examples are provided in which studies successfully demonstrate a measure of immunocompetence through alterations in disease resistance and organism survival to a realized pathogenic threat. Consequently, this review highlights the potential to advance our current understanding of the ecological and evolutionary significance of environmental stressor related immune dysfunction. Furthermore, the potential for the advancement of our understanding of the immune system of marine invertebrates, through the incorporation of newly emerging and novel molecular techniques, is emphasized.


Asunto(s)
Ecosistema , Inmunidad Celular/inmunología , Inmunidad Humoral/inmunología , Inmunidad Innata/inmunología , Invertebrados/inmunología , Estrés Fisiológico/inmunología , Animales , Péptidos Catiónicos Antimicrobianos/inmunología , Biología Marina , Océanos y Mares , Fagocitosis/inmunología , Estallido Respiratorio/inmunología , Especificidad de la Especie
11.
J Antimicrob Chemother ; 65(3): 569-75, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20053693

RESUMEN

OBJECTIVES: We describe rates of success for two-stage revision of prosthetic joint infection (PJI), including data on reimplantation microbiology. METHODS: We retrospectively collected data from all the cases of PJI that were managed with two-stage revision over a 4 year period. Patients were managed with an antibiotic-free period before reimplantation, in order to confirm, clinically and microbiologically, that infection was successfully treated. RESULTS: One hundred and fifty-two cases were identified. The overall success rate (i.e. retention of the prosthesis over 5.75 years of follow-up) was 83%, but was 89% for first revisions and 73% for re-revisions [hazard ratio = 2.9, 95% confidence interval (CI) 1.2-7.4, P = 0.023]. Reimplantation microbiology was frequently positive (14%), but did not predict outcome (hazard ratio = 1.3, 95% CI 0.4-3.7, P = 0.6). Furthermore, most unplanned debridements following the first stage were carried out before antibiotics were stopped (25 versus 2 debridements). CONCLUSIONS: We did not identify evidence supporting the use of an antibiotic-free period before reimplantation and routine reimplantation microbiology. Re-revision was associated with a significantly worse outcome.


Asunto(s)
Antibacterianos/uso terapéutico , Artropatías/tratamiento farmacológico , Artropatías/cirugía , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Infecciones Relacionadas con Prótesis/cirugía , Reimplantación , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
12.
Clin Oncol (R Coll Radiol) ; 21(8): 610-6, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19695849

RESUMEN

AIMS: To determine whether primary care trusts' agreement or refusal to fund sorafenib or sunitinib affects outcomes for patients with metastatic renal cell carcinoma. MATERIALS AND METHODS: This retrospective audit was conducted in a tertiary referral centre for urological cancer. Requests to prescribe drugs not approved by the National Institute for Health and Clinical Excellence are recorded on a trust database. We obtained details of all requests made for sunitinib and sorafenib for patients with renal cell carcinoma since licence in 2006. Outcome measures analysed were overall survival measured from the date of request for funding and hospital resource use as measured from Payment by Results data. Known prognostic factors and the patient's Index of Multiple Deprivation score were assessed at baseline as potential confounders of survival difference. RESULTS: Seventy-nine patients were identified. The groups were similar with respect to prognostic factors and Index of Multiple Deprivation scores. Thirty-seven and eight patients had funding approved for sunitinib and sorafenib, respectively; 21 and 13 were turned down. Seven patients who were denied funding received one or other of these drugs by self-funding treatment. Survival was longer for patients who received treatment with a drug for which they had applied for funding than for those who did not (hazards ratio 0.46; 95% confidence interval 0.21-1.01; chi(2)=3.80; 1 d.f.; P=0.05); the advantage was similar for patients receiving sunitinib (hazards ratio=0.49; 95% confidence interval 0.18-1.36; chi(2)=1.86; 1 d.f.; P=0.17) and sorafenib (hazard ratio=0.44; 95% confidence interval 0.11-1.69; chi(2)=1.58; 1 d.f.; P=0.21). Overall National Health Service resource use apart from funding for the renal cancer drugs was similar for both groups. CONCLUSIONS: Compared with patients receiving treatment, patients denied access to sunitinib and sorafenib had substantially worse survival outcomes, despite receiving treatment from the same clinical team. Access to the new drugs did not have an effect on overall use of National Health Service resources by funded patients. Modern treatments for advanced renal cancer should be available to all National Health Service patients with the disease.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/patología , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/patología , Inhibidores de Proteínas Quinasas/uso terapéutico , Bencenosulfonatos/farmacología , Carcinoma de Células Renales/mortalidad , Femenino , Humanos , Indoles/farmacología , Riñón/patología , Neoplasias Renales/mortalidad , Masculino , Auditoría Médica , Metástasis de la Neoplasia , Niacinamida/análogos & derivados , Compuestos de Fenilurea , Piridinas/farmacología , Pirroles/farmacología , Sorafenib , Sunitinib , Análisis de Supervivencia , Reino Unido
13.
Biochem Soc Trans ; 34(Pt 3): 385-8, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16709168

RESUMEN

Cell cycle calcium signals are generated by inositol trisphosphate-mediated release of calcium from internal stores [Ciapa, Pesando, Wilding and Whitaker (1994) Nature (London) 368, 875-878; Groigno and Whitaker (1998) Cell 92, 193-204]. The major internal calcium store is the ER (endoplasmic reticulum): the spatial organization of the ER during mitosis is important in defining a microdomain around the nucleus and mitotic spindle in early Drosophila embryos [Parry, McDougall and Whitaker (2005) J. Cell Biol. 171, 47-59]. Nuclear divisions in syncytial Drosophila embryos are accompanied by both cortical and nuclear localized calcium transients. Mitosis is prevented by the InsP(3) antagonists Xestospongin C and heparin. Nuclear-localized transients and cortical transients rely on extraembryonic calcium, suggesting that ER calcium levels are maintained by calcium influx.


Asunto(s)
Señalización del Calcio/fisiología , Núcleo Celular/fisiología , Drosophila melanogaster/embriología , Retículo Endoplásmico/fisiología , Células Gigantes/fisiología , Microdominios de Membrana/fisiología , Huso Acromático/fisiología , Animales , Núcleo Celular/química , Drosophila melanogaster/metabolismo , Retículo Endoplásmico/química , Células Gigantes/química , Microdominios de Membrana/química , Huso Acromático/química
14.
Aquat Toxicol ; 69(4): 311-25, 2004 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-15312716

RESUMEN

The interactive effects of temperature and copper on immune function and consequently disease susceptibility of the marine mussel, Mytilus edulis were investigated. Two studies were carried out, the first involved sequential exposure to copper at 0.02 and 0.05 ppm followed by the bacterium Vibrio tubiashii. In the second study, mussels were simultaneously exposed to copper and V. tubiashii. Both studies were carried out at 10 and 15 degrees C, to ascertain whether temperature had an additional effect on immunocompetence. A multi-assay approach was used to obtain an overall view of immune function in the mussels. Assays carried out included total and differential haemocyte counts, production of intracellular superoxide and phagocytosis by haemocytes. Data are presented showing significant effects on immune parameters of sequential and simultaneous exposure to copper and V. tubiashii at 10 and 15 degrees C. Each of the factors considered were shown to have a significant effect on at least one of the immune parameters measured. There were also significant effects due to the interaction of these factors. The response of total and differential blood cell counts to copper were shown to alter, if mussels were exposed in a sequential manner as opposed to simultaneous exposure. The results confirmed that the immune system of M. edulis is susceptible to copper at relatively low concentrations. Furthermore, the effects of copper alter with environmental variables, including temperature and the presence of a potential pathogen. The complexity of the interactions demonstrate that extrapolation of data obtained from single stressor studies into field situations could give a misleading picture.


Asunto(s)
Bivalvos/inmunología , Cobre/toxicidad , Inmunocompetencia/efectos de los fármacos , Temperatura , Animales , Bivalvos/microbiología , Recuento de Células Sanguíneas , Proteínas Sanguíneas/metabolismo , Relación Dosis-Respuesta a Droga , Hemocitos/inmunología , Inmunocompetencia/inmunología , Nitroazul de Tetrazolio , Fagocitosis/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Vibrio/inmunología
15.
Parasitology ; 126(Pt 3): 225-9, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12666880

RESUMEN

As has been shown previously, immunologically intact mice with patent Schistosoma mansoni infections had a significantly lower mean platelet number than intact uninfected mice (P<0.0001). However, platelet numbers in T-cell deprived mice with patent infections were not significantly different from those in uninfected T-cell deprived mice. Also, platelet counts in both the infected and uninfected T-cell deprived groups were not significantly different from those in intact uninfected mice. The S. mansoni-induced thrombocytopaenia in mice is thus seemingly immune dependent. Immunologically intact mice with chronic 12-week-old S. mansoni infections had IgG antibodies that were reactive in an ELISA-type assay with whole fixed platelets of both mouse and human origin. In Western immunoblots the IgG antibodies from chronically-infected mice reacted in particular against mouse and human platelet antigens of 90, 37 and 30 kDa. Antisera raised from 2 rabbits, immunized respectively with mouse and human platelet antigens, cross-reacted with antigens of the larval, adult worm and egg stages of S. mansoni. These results support the hypothesis that an anti-platelet antibody response may be the cause of the thrombocytopaenia observed in mice with patent schistosome infections.


Asunto(s)
Plaquetas/inmunología , Schistosoma mansoni/fisiología , Esquistosomiasis/complicaciones , Esquistosomiasis/inmunología , Trombocitopenia/complicaciones , Trombocitopenia/inmunología , Animales , Anticuerpos/inmunología , Femenino , Humanos , Inmunoglobulina G/inmunología , Masculino , Ratones , Ratones Endogámicos CBA , Recuento de Plaquetas , Conejos , Esquistosomiasis/parasitología , Timo/cirugía , Factores de Tiempo
16.
Parasitology ; 126(Pt 3): 231-4, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12666881

RESUMEN

Aqueous extracts of Schistosoma mansoni eggs have been shown to have fibrinolytic activity inhibitable by a serine protease inhibitor. Fibrinolytic activity was not present in extracts of either adult worms or cercariae. A 27 kDa enzyme that was proteolytically active on fibrinogen in zymography and that degraded fibrinogen in a pattern similar to that of plasmin, is presumed to be responsible for the schistosome egg fibrinolytic activity. Anti-human fibrinogen antisera were shown to have antibodies that cross-reacted with mouse fibrinogen in Western immunoblots. Electroblotted sera from S. mansoni-infected and control uninfected mice displayed different antigenic profiles when probed with the cross-reactive anti-human fibrinogen antibodies, suggesting an alteration in mouse host fibrinogen metabolism as a result of the parasitic infection. We discuss the possibility that modulation of fibrinogen metabolism is a factor in a recently discovered anti-atherogenic effect exerted by schistosomes.


Asunto(s)
Fibrinógeno/metabolismo , Fibrinólisis , Óvulo/enzimología , Enfermedades de los Roedores/metabolismo , Enfermedades de los Roedores/parasitología , Schistosoma mansoni/enzimología , Animales , Ratones , Esquistosomiasis mansoni/fisiopatología
17.
Clin Sci (Lond) ; 100(6): 661-5, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11352783

RESUMEN

The effect of smoking on androgen levels is important given the recent interest in the link between low levels of androgens and the development of cardiovascular disease. Numerous studies examining the effects of cigarette smoking on the levels of total and free testosterone have reported conflicting findings, but there has been no accurate assessment of the effects of cigarette smoking on the levels of bioavailable testosterone [not bound to sex hormone-binding globulin (SHBG)]. We attempted to determine whether smoking affects the level of bioavailable testosterone. We undertook a case-control study of 25 healthy male smokers and 25 healthy never-smokers, matched by age and body mass index. Early morning levels of total, free and bioavailable testosterone, 17beta-oestradiol, SHBG and cotinine were determined and compared between the two groups. Levels of total (18.5+/-4.6 nM versus 15.1+/-4.9 nM, P=0.01) and free testosterone (462+/-91 pM versus 402+/-93 pM, P=0.03) were found to be higher in smokers compared with non-smokers respectively, as was SHBG (34.1+/-12.8 versus 28.1+/-9.0 nM, P=0.06). There were no significant differences in the levels of bioavailable testosterone (3.78+/-1.59 versus 3.51+/-1.26 nM, P=0.49) or 17beta-oestradiol (44.5+/-11.4 versus 42.3+/-11.5 pM, P=0.50) between smokers and non-smokers respectively. These data suggest that cigarette smoking has no significant effect on the biologically active fraction of testosterone, but may influence the levels of total and free testosterone through changes in the levels of SHBG.


Asunto(s)
Fumar/sangre , Testosterona/sangre , Adolescente , Adulto , Disponibilidad Biológica , Estudios de Casos y Controles , Estradiol/sangre , Humanos , Masculino , Persona de Mediana Edad , Globulina de Unión a Hormona Sexual/análisis
19.
Mol Microbiol ; 34(3): 607-19, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10564501

RESUMEN

whiI is one of several loci originally described as essential for sporulation in Streptomyces coelicolor A3(2). We have characterized whiI at the molecular level. It encodes an atypical member of the response regulator family of proteins, lacking at least two of the residues strongly conserved in the conventional phosphorylation pocket. It is not adjacent to a potential sensor kinase gene. Fifteen mutant alleles of whiI were sequenced, revealing, among others, six mutations affecting conserved amino acids, several frameshift mutations and one mutation in the promoter. The whiI promoter is specifically transcribed by the sporulation-specific sigmaWhiG-containing form of RNA polymerase. Transcription of whiI is temporally controlled, reaching a maximum level coincident with the formation of spores. Further transcriptional studies suggested that WhiI is involved directly or indirectly in repressing its own expression and that of another sigmaWhiG-dependent sporulation-specific regulatory gene, whiH.


Asunto(s)
Proteínas Bacterianas , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Proteínas Represoras/fisiología , Streptomyces/fisiología , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Prueba de Complementación Genética , Datos de Secuencia Molecular , Mutación , Regiones Promotoras Genéticas , Proteínas Represoras/química , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Esporas Bacterianas/genética , Esporas Bacterianas/fisiología , Streptomyces/genética
20.
Am J Clin Pathol ; 107(1): 64-7, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8980369

RESUMEN

Blood was collected from 684 healthy volunteers and examined for total and differential white blood cell (WBC) counts. A subgroup also was tested for numbers of T cells, B cells, and CD4 and CD8 subsets. Smoking status and alcohol consumption were determined by means of questionnaire, and smoking status was verified with serum cotinine concentration. High smoking rate was associated with increases in all counts. Former smokers abstinent less than 5 years still demonstrated elevated counts, whereas those abstinent more than 5 years had WBC counts comparable to those in persons who were never smokers. Compared with levels in those who had never smoked, total WBC counts were 27% higher in current smokers and 14% higher in former smokers who were abstinent for less than 5 years. Lymphocyte counts were 9% higher in those consuming more than one alcoholic drink per day than in those consuming less alcohol, but drinking was not associated with other cell populations.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Leucocitos/patología , Leucocitosis/etiología , Fumar/efectos adversos , Adulto , Femenino , Humanos , Recuento de Leucocitos , Leucocitosis/patología , Subgrupos Linfocitarios , Masculino
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