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1.
Ultrasound Obstet Gynecol ; 57(4): 573-581, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33620113

RESUMEN

OBJECTIVE: Few large cohort studies have reported data on maternal, fetal, perinatal and neonatal outcomes associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in pregnancy. We report the outcome of infected pregnancies from a collaboration formed early during the pandemic between the investigators of two registries, the UK and Global Pregnancy and Neonatal outcomes in COVID-19 (PAN-COVID) study and the American Academy of Pediatrics (AAP) Section on Neonatal-Perinatal Medicine (SONPM) National Perinatal COVID-19 Registry. METHODS: This was an analysis of data from the PAN-COVID registry (1 January to 25 July 2020), which includes pregnancies with suspected or confirmed maternal SARS-CoV-2 infection at any stage in pregnancy, and the AAP-SONPM National Perinatal COVID-19 registry (4 April to 8 August 2020), which includes pregnancies with positive maternal testing for SARS-CoV-2 from 14 days before delivery to 3 days after delivery. The registries collected data on maternal, fetal, perinatal and neonatal outcomes. The PAN-COVID results are presented overall for pregnancies with suspected or confirmed SARS-CoV-2 infection and separately in those with confirmed infection. RESULTS: We report on 4005 pregnant women with suspected or confirmed SARS-CoV-2 infection (1606 from PAN-COVID and 2399 from AAP-SONPM). For obstetric outcomes, in PAN-COVID overall and in those with confirmed infection in PAN-COVID and AAP-SONPM, respectively, maternal death occurred in 0.5%, 0.5% and 0.2% of cases, early neonatal death in 0.2%, 0.3% and 0.3% of cases and stillbirth in 0.5%, 0.6% and 0.4% of cases. Delivery was preterm (< 37 weeks' gestation) in 12.0% of all women in PAN-COVID, in 16.1% of those women with confirmed infection in PAN-COVID and in 15.7% of women in AAP-SONPM. Extreme preterm delivery (< 27 weeks' gestation) occurred in 0.5% of cases in PAN-COVID and 0.3% in AAP-SONPM. Neonatal SARS-CoV-2 infection was reported in 0.9% of all deliveries in PAN-COVID overall, in 2.0% in those with confirmed infection in PAN-COVID and in 1.8% in AAP-SONPM; the proportions of neonates tested were 9.5%, 20.7% and 87.2%, respectively. The rates of a small-for-gestational-age (SGA) neonate were 8.2% in PAN-COVID overall, 9.7% in those with confirmed infection and 9.6% in AAP-SONPM. Mean gestational-age-adjusted birth-weight Z-scores were -0.03 in PAN-COVID and -0.18 in AAP-SONPM. CONCLUSIONS: The findings from the UK and USA registries of pregnancies with SARS-CoV-2 infection were remarkably concordant. Preterm delivery affected a higher proportion of women than expected based on historical and contemporaneous national data. The proportions of pregnancies affected by stillbirth, a SGA infant or early neonatal death were comparable to those in historical and contemporaneous UK and USA data. Although maternal death was uncommon, the rate was higher than expected based on UK and USA population data, which is likely explained by underascertainment of women affected by milder or asymptomatic infection in pregnancy in the PAN-COVID study, although not in the AAP-SONPM study. The data presented support strong guidance for enhanced precautions to prevent SARS-CoV-2 infection in pregnancy, particularly in the context of increased risks of preterm delivery and maternal mortality, and for priority vaccination of pregnant women and women planning pregnancy. Copyright © 2021 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
COVID-19 , Complicaciones Infecciosas del Embarazo , Resultado del Embarazo/epidemiología , Adulto , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/transmisión , Femenino , Retardo del Crecimiento Fetal/diagnóstico , Retardo del Crecimiento Fetal/epidemiología , Retardo del Crecimiento Fetal/virología , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Masculino , Mortalidad Materna , Pandemias , Muerte Perinatal , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/prevención & control , Nacimiento Prematuro/diagnóstico , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/virología , Sistema de Registros , Mortinato/epidemiología , Reino Unido/epidemiología , Estados Unidos/epidemiología
2.
Ultrasound Obstet Gynecol ; 55(5): 586-592, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32180292

RESUMEN

OBJECTIVES: There are limited case series reporting the impact on women affected by coronavirus during pregnancy. In women affected by severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), the case fatality rate appears higher in those affected in pregnancy compared with non-pregnant women. We conducted a rapid review to guide health policy and management of women affected by COVID-19 during pregnancy, which was used to develop the Royal College of Obstetricians and Gynaecologists' (RCOG) guidelines on COVID-19 infection in pregnancy. METHODS: Searches were conducted in PubMed and MedRxiv to identify primary case reports, case series, observational studies and randomized controlled trials describing women affected by coronavirus in pregnancy. Data were extracted from relevant papers. This review has been used to develop guidelines with representatives of the Royal College of Paediatrics and Child Health (RCPCH) and RCOG who provided expert consensus on areas in which data were lacking. RESULTS: From 9965 search results in PubMed and 600 in MedRxiv, 21 relevant studies, all of which were case reports or case series, were identified. From reports of 32 women to date affected by COVID-19 in pregnancy, delivering 30 babies (one set of twins, three ongoing pregnancies), seven (22%) were asymptomatic and two (6%) were admitted to the intensive care unit (ICU), one of whom remained on extracorporeal membrane oxygenation. No maternal deaths have been reported to date. Delivery was by Cesarean section in 27 cases and by vaginal delivery in two, and 15 (47%) delivered preterm. There was one stillbirth and one neonatal death. In 25 babies, no cases of vertical transmission were reported; 15 were reported as being tested with reverse transcription polymerase chain reaction after delivery. Case fatality rates for SARS and MERS were 15% and 27%, respectively. SARS was associated with miscarriage or intrauterine death in five cases, and fetal growth restriction was noted in two ongoing pregnancies affected by SARS in the third trimester. CONCLUSIONS: Serious morbidity occurred in 2/32 women with COVID-19, both of whom required ICU care. Compared with SARS and MERS, COVID-19 appears less lethal, acknowledging the limited number of cases reported to date and that one woman remains in a critical condition. Preterm delivery affected 47% of women hospitalized with COVID-19, which may put considerable pressure on neonatal services if the UK's reasonable worst-case scenario of 80% of the population being affected is realized. Based on this review, RCOG, in consultation with RCPCH, developed guidance for delivery and neonatal care in pregnancies affected by COVID-19, which recommends that delivery mode be determined primarily by obstetric indication and recommends against routine separation of affected mothers and their babies. We hope that this review will be helpful for maternity and neonatal services planning their response to COVID-19. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/complicaciones , Neumonía Viral/complicaciones , Complicaciones Infecciosas del Embarazo , COVID-19 , Bases de Datos Factuales , Femenino , Desarrollo Fetal , Humanos , Pandemias , Embarazo , Resultado del Embarazo , Nacimiento Prematuro , SARS-CoV-2
3.
Haemophilia ; 24(3): e84-e92, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29359417

RESUMEN

INTRODUCTION: Prophylaxis with extended half-life factor VIII (FVIII) is approved for haemophilia A, but data regarding routine clinical use are limited. AIM: To assess real-world experience of ADYNOVATE® (Antihemophilic Factor (Recombinant), PEGylated prophylaxis in children and adults with haemophilia A. METHODS: A retrospective chart review was conducted in three US haemophilia treatment centres. Records of all patients who began Adynovate prophylaxis in routine clinical practice were identified. Demographic, clinical and patient-reported information beginning 6 months before initiation of Adynovate until the record review was analysed. RESULTS: Fifteen patients (aged 9 months to 28 years), with median 9 months' use of Adynovate (range 1-15 months), were identified. All had switched from another prophylactic regimen, 13 (87%) from standard half-life recombinant FVIII. Nine (60%) patients had ≥1 bleed within 6 months preswitch. The most frequent reason for switching was to reduce infusion frequency (14 patients). After switching, infusion frequency reduced for 13 patients, and overall weekly factor consumption decreased by 19%. Eight (53%) patients had no bleeds postswitch, three (20%) had spontaneous joint bleeds (vs four pre-switch), and three (20%) had only mild traumatic bleeds. Patient/parental satisfaction with Adynovate was documented as positive in 13 of 15 (87%) cases; 2 patients were not satisfied and discontinued Adynovate. No adverse events were considered related to Adynovate. CONCLUSION: In patients who switched from a standard half-life FVIII to Adynovate prophylaxis in routine clinical practice, bleeding control was generally improved or maintained, with a lower infusion frequency and factor consumption in most patients.


Asunto(s)
Factor VIII/química , Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Polietilenglicoles/química , Adolescente , Adulto , Factor VIII/farmacología , Hemofilia A/complicaciones , Humanos , Masculino , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto Joven
4.
Haemophilia ; 23(6): 904-909, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28780770

RESUMEN

INTRODUCTION: Subcutaneous (SQ) vaccination has emerged as standard of care in children with severe bleeding disorders to reduce unnecessary factor exposure and avoid provoking an intramuscular bleed, but little is known about comparative immunogenicity to intramuscular (IM) vaccination. AIM: To confirm immunogenicity of Diphtheria Tetanus acellular Pertussis (DTaP) vaccines administered SQ to individuals <6 years old with haemophilia. METHODS: We performed a retrospective and prospective pilot study of tetanus and diphtheria antibody titres among patients evaluated at our Haemophilia Treatment Centre between 2015-2016. Children with haemophilia who had received three to four doses of DTaP containing vaccine administered SQ were eligible. RESULTS: Eight children met inclusion criteria. The mean age at the time of diphtheria and tetanus antibody testing was 21.1±17.8 months. All children who received SQ diphtheria and tetanus developed a positive antibody titre to both antigens. There was no statistically significant difference in distribution of titre values. The average time between the last dose of vaccine and antibody testing was 6.6±3.9 months among SQ vaccinated subjects. Minor injection site reactions were common with SQ vaccines. CONCLUSION: SQ administration of diphtheria and tetanus vaccination appears to be immunogenic in a pilot study of Haemophilia patients and supports this practice as the standard of care for this population.


Asunto(s)
Vacunas contra Difteria, Tétanos y Tos Ferina Acelular/inmunología , Hemofilia A/inmunología , Hemofilia B/inmunología , Vacunación/métodos , Anticuerpos Antibacterianos/inmunología , Preescolar , Vacunas contra Difteria, Tétanos y Tos Ferina Acelular/administración & dosificación , Humanos , Lactante , Inyecciones Intramusculares , Inyecciones Subcutáneas , Masculino , Proyectos Piloto , Estudios Prospectivos , Estudios Retrospectivos , Literatura de Revisión como Asunto
5.
Haemophilia ; 23(2): 238-246, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27891721

RESUMEN

INTRODUCTION: Primary factor VIII (FVIII) prophylaxis is the optimal treatment in children with severe haemophilia A. They are expected to benefit from extended half-life (T1/2 ) FVIII coverage by reduced infusion frequency while maintaining haemostatic efficacy. AIMS: To determine immunogenicity, pharmacokinetics (PK), efficacy, safety and quality of life of prophylaxis with a polyethylene glycol (peg)-ylated FVIII (BAX 855) based on full-length recombinant FVIII (ADVATE) in paediatric previously treated patients (PTPs) with severe haemophilia A. METHODS: PTPs <12 years without history of FVIII inhibitors received twice-weekly infusions of 50 ± 10 IU kg-1 BAX 855 for ≥50 exposure days. Prophylactic dose increases to ≤80 IU kg-1 were allowed under predefined conditions. PK was evaluated after single infusions of 60 ± 5 IU kg-1 . RESULTS: T1/2 and mean residence time were extended 1.3- to 1.5-fold compared to ADVATE (n = 31), depending on the analysis used. The point estimate for the mean annualized bleeding rate in 66 subjects receiving a median of 1.9 weekly infusions of 51.3 IU kg-1 of BAX 855 each was 3.04 (median 2.0); 1.10 (median 0) for joint and 1.16 (median 0) for spontaneous bleeds. Overall, 38% of subjects had zero bleeds. No bleeds were severe. Haemostatic efficacy was rated excellent or good for 90% of bleeds; 91% were treated with one or two infusions. In 8/14 subjects all target joints resolved. No subject developed FVIII inhibitors or persistent binding antibodies that affected safety or efficacy. No adverse reactions occurred. CONCLUSION: Twice-weekly prophylaxis with BAX 855 was safe and efficacious in paediatric PTPs with severe haemophilia A.


Asunto(s)
Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Niño , Preescolar , Femenino , Hemofilia A/patología , Humanos , Masculino , Estudios Prospectivos , Calidad de Vida
7.
Ultrasound Obstet Gynecol ; 56(1): 122-123, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32608568
9.
Ultrasound Obstet Gynecol ; 44(6): 688-92, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24585483

RESUMEN

OBJECTIVES: Pregnancy complications, particularly those associated with placental dysfunction, occur more frequently in nulliparous than in parous women. This difference may be a consequence of improved trophoblastic invasion and, as a result, improved placental function following previous pregnancy. Placental dysfunction in cases of fetal growth restriction may be identified by ultrasound assessment of fetoplacental hemodynamics and amniotic fluid volume. In this prospective observational study, we investigated whether differences in these measures of placental function exist between nulliparous and parous women, prior to active labor. METHODS: Over a 2-year period, 456 nulliparous and 152 parous women with uncomplicated singleton pregnancies were recruited to this prospective observational study. Each participant underwent an ultrasound assessment prior to active labor, during which fetal biometry, umbilical artery, middle cerebral artery and umbilical venous Dopplers, as well as amniotic fluid volume, were assessed. All cases were followed up within 48 h of delivery. Ultrasound parameters and intrapartum outcomes were then compared between the nulliparous and parous groups. RESULTS: Compared with nulliparous women, parous women had significantly higher fetal middle cerebral artery pulsatility index, cerebroplacental ratio and amniotic fluid volume. In nulliparous women, middle cerebral artery flow rate was also significantly higher and represented a greater percentage of umbilical venous flow than was observed in parous women. CONCLUSION: Prior to the active phase of labor, ultrasound parameters indicative of placental function differ significantly between nulliparous and parous pregnancy, even amongst an uncomplicated, low-risk cohort.


Asunto(s)
Líquido Amniótico/fisiología , Arteria Cerebral Media/fisiología , Paridad/fisiología , Placenta/fisiología , Ultrasonografía Prenatal , Arterias Umbilicales/fisiología , Venas Umbilicales/fisiología , Adolescente , Adulto , Líquido Amniótico/diagnóstico por imagen , Femenino , Hemodinámica , Humanos , Modelos Lineales , Persona de Mediana Edad , Arteria Cerebral Media/diagnóstico por imagen , Embarazo , Estudios Prospectivos , Ultrasonografía Doppler , Arterias Umbilicales/diagnóstico por imagen , Venas Umbilicales/diagnóstico por imagen , Adulto Joven
10.
Eur J Obstet Gynecol Reprod Biol ; 276: 161-167, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35914420

RESUMEN

OBJECTIVE: To assess perinatal outcomes for pregnancies affected by suspected or confirmed SARS-CoV-2 infection. METHODS: Prospective, web-based registry. Pregnant women were invited to participate if they had suspected or confirmed SARS-CoV-2 infection between 1st January 2020 and 31st March 2021 to assess the impact of infection on maternal and perinatal outcomes including miscarriage, stillbirth, fetal growth restriction, pre-term birth and transmission to the infant. RESULTS: Between April 2020 and March 2021, the study recruited 8239 participants who had suspected or confirmed SARs-CoV-2 infection episodes in pregnancy between January 2020 and March 2021. Maternal death affected 14/8197 (0.2%) participants, 176/8187 (2.2%) of participants required ventilatory support. Pre-eclampsia affected 389/8189 (4.8%) participants, eclampsia was reported in 40/ 8024 (0.5%) of all participants. Stillbirth affected 35/8187 (0.4 %) participants. In participants delivering within 2 weeks of delivery 21/2686 (0.8 %) were affected by stillbirth compared with 8/4596 (0.2 %) delivering ≥ 2 weeks after infection (95 % CI 0.3-1.0). SGA affected 744/7696 (9.3 %) of livebirths, FGR affected 360/8175 (4.4 %) of all pregnancies. Pre-term birth occurred in 922/8066 (11.5%), the majority of these were indicated pre-term births, 220/7987 (2.8%) participants experienced spontaneous pre-term births. Early neonatal deaths affected 11/8050 livebirths. Of all neonates, 80/7993 (1.0%) tested positive for SARS-CoV-2. CONCLUSIONS: Infection was associated with indicated pre-term birth, most commonly for fetal compromise. The overall proportions of women affected by SGA and FGR were not higher than expected, however there was the proportion affected by stillbirth in participants delivering within 2 weeks of infection was significantly higher than those delivering ≥ 2 weeks after infection. We suggest that clinicians' threshold for delivery should be low if there are concerns with fetal movements or fetal heart rate monitoring in the time around infection. The proportion affected by pre-eclampsia amongst participants was not higher than would be expected, although we report a higher than expected proportion affected by eclampsia. There appears to be no effect on birthweight or congenital malformations in women affected by SARS-CoV-2 infection in pregnancy and neonatal infection is uncommon. This study reflects a population with a range of infection severity for SARS-COV-2 in pregnancy, generalisable to whole obstetric populations.


Asunto(s)
COVID-19 , Eclampsia , Preeclampsia , Complicaciones Infecciosas del Embarazo , Nacimiento Prematuro , COVID-19/complicaciones , COVID-19/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Preeclampsia/epidemiología , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Estudios Prospectivos , SARS-CoV-2 , Mortinato/epidemiología
12.
Blood Adv ; 4(22): 5785-5796, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33232473

RESUMEN

Preventing factor VIII (FVIII) inhibitors following replacement therapies with FVIII products in patients with hemophilia A remains an unmet medical need. Better understanding of the early events of evolving FVIII inhibitors is essential for risk identification and the design of novel strategies to prevent inhibitor development. The Hemophilia Inhibitor Previously Untreated Patients (PUPs) Study (HIPS; www.clinicaltrials.gov #NCT01652027) is the first prospective cohort study to evaluate comprehensive changes in the immune system during the first 50 exposure days (EDs) to FVIII in patients with severe hemophilia A. HIPS participants were enrolled prior to their first exposure to FVIII or blood products ("true PUPs") and were evaluated for different immunological and clinical parameters at specified time points during their first 50 EDs to a single source of recombinant FVIII. Longitudinal antibody data resulting from this study indicate that there are 4 subgroups of patients expressing distinct signatures of FVIII-binding antibodies. Subgroup 1 did not develop any detectable FVIII-binding immunoglobulin G (IgG) antibodies. Subgroup 2 developed nonneutralizing, FVIII-binding IgG1 antibodies, but other FVIII-binding IgG subclasses were not observed. Subgroup 3 developed transient FVIII inhibitors associated with FVIII-binding IgG1 antibodies, similar to subgroup 2. Subgroup 4 developed persistent FVIII inhibitors associated with an initial development of high-affinity, FVIII-binding IgG1 antibodies, followed by IgG3 and IgG4 antibodies. Appearance of FVIII-binding IgG3 was always associated with persistent FVIII inhibitors and the subsequent development of FVIII-binding IgG4. Some of the antibody signatures identified in HIPS could serve as candidates for early biomarkers of FVIII inhibitor development.


Asunto(s)
Hemofilia A , Hemostáticos , Biomarcadores , Factor VIII , Hemofilia A/tratamiento farmacológico , Humanos , Inmunoglobulina G , Estudios Prospectivos
13.
Int J Epidemiol ; 12(4): 414-8, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6654560

RESUMEN

An extensive area of rural Ireland was monitored in detail for natural background radiation (NBR); average background radiation values were derived for all District Electoral Divisions (DEDs) in this area. Cancer mortality rates were calculated for the DEDs aggregated according to average NBR. No association was apparent between cancer mortality rates and levels of natural background radiation.


Asunto(s)
Radiación de Fondo , Neoplasias/mortalidad , Radiación Ionizante , Radiación de Fondo/efectos adversos , Femenino , Rayos gamma , Humanos , Irlanda , Masculino , Neoplasias/etiología , Neoplasias Inducidas por Radiación/etiología , Neoplasias Inducidas por Radiación/mortalidad , Radiación Ionizante/efectos adversos
14.
J Am Geriatr Soc ; 42(2): 146-9, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8126326

RESUMEN

OBJECTIVES: To assess the prevalence of typical clinical features and need for treatment of small intestinal bacterial overgrowth (SIBO) in the elderly. DESIGN: Random selection of patients, regardless of their nutritional status. SETTING: Acute admissions ward in the Dept. of Medicine for the Elderly. PATIENTS: Thirty elderly patients between 68 and 90 years of age. MEASUREMENTS: Active clinical problems, including the presence of recent weight loss and diarrhea, were recorded. Routine blood tests, including serum vitamin B12, red cell folate, albumin and calcium, and qualitative small bowel bacteriology results, were analyzed. The effect of age on all variables was studied. RESULTS: Twenty of the 30 small bowel aspirates had proven SIBO, and strict anaerobes were isolated in 15. The mean blood test values did not differ significantly between culture-positive and culture-negative patients. There was no significant correlation between those variables and the total bacterial counts. Of the 20 proven SIBO cases, eight had anemia, five had hypoalbuminemia, five had diarrhea, four complained of recent weight loss, and none had B12 deficiency. Alternative causes other than SIBO were identified for many of these abnormalities. Advancing age correlated significantly with rising counts of small bowel strict anaerobes. CONCLUSIONS: These data suggest that age may be a predisposing factor in the development of anaerobic overgrowth but that SIBO is a benign entity in the elderly. Contrary to previous recommendations, treatment of this condition is not routinely indicated.


Asunto(s)
Bacterias/crecimiento & desarrollo , Intestino Delgado/microbiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Recuento de Colonia Microbiana , Femenino , Humanos , Masculino
15.
Eur J Pharmacol ; 70(2): 129-37, 1981 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-7021169

RESUMEN

The relationship between angiotensin conversion and release of prostaglandins (PGs) were studied in isolated, perfused, mesenteric vasculature of rats. PGs in the mesenteric effluent were detected by bovine coronary artery and rat stomach strip, and by radioimmunoassay of 6-oxo-PGF1 alpha and PGE2. Angiotensin II (AII) was assayed simultaneously using rabbit aorta. Both angiotensin I (AI) and AII released a prostacyclin (PGI2)-like substance, but little PGE2 from the mesentery, AII being 5 times more potent. Indomethacin (2.8 micrometers) abolished angiotensin-induced release of PGI2. Of the AI (0.2--1.5 nmol) injected into the perfusion medium, 3--8% was converted to AII in passage through the mesentery. Captopril (4 micrometers), infused through the mesentery, inhibited AI-induced PGI2 release, but did not affect release induced by AII. Release of the PGI2-like substance by higher doses of AI (2--20 nmol) in the presence of captopril was always accompanied by concomitant contraction of rabbit aorta, indicating residual conversion of AI. Infusion of (Sar1, Ala8)AII (3--30 nM) through the mesentery abolished PGI2 release by both peptides. By choosing doses of AI and AII which produce equivalent amounts of AII in the mesenteric effluent, it appeared that AII generated locally in the mesenteric vasculature was a more effective stimulus for PGI2 generation than AII in the perfusion fluid. There is no evidence for intrinsic activity of AI, and release of the PGI2-like substance appears to be mediated through an AII receptor.


Asunto(s)
Angiotensinas/metabolismo , Epoprostenol/metabolismo , Arterias Mesentéricas/metabolismo , Músculo Liso Vascular/metabolismo , Prostaglandinas/metabolismo , Angiotensina I/metabolismo , Angiotensina II/biosíntesis , Angiotensinas/farmacología , Animales , Captopril/farmacología , Técnicas In Vitro , Masculino , Arterias Mesentéricas/efectos de los fármacos , Ratas , Saralasina/farmacología
16.
Resuscitation ; 36(1): 65-70, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9547846

RESUMEN

Brainstem auditory evoked responses (BAER) are routinely used to monitor brainstem function in hospitalized comatose patients. We used a rat model of cardiac arrest and resuscitation to explore the possibility that the BAER, monitored during and immediately after cardiopulmonary resuscitation (CPR), could be used to determine whether the CPR was effective in restoring brainstem blood flow. Long-Evans rats were subjected to 7 min of cardiac arrest, induced by chest compression under Ketamine anesthesia sufficient to mechanically prevent the heart from pumping blood and were then resuscitated using a standard CPR protocol. During CPR, click stimuli were applied to one ear at 11/s and BAER averages recorded every 15 s. In three rats the BAER did not return after CPR; none of these rats respired spontaneously and all died. In 33 rats the BAER did return; within 15 min after the start of CPR BAER peak latencies decreased rapidly, increased again and then decreased. If the increase in the latency of the N2 peak was less than 0.3 ms, then the rat survived. If it was greater than 0.35 ms the rat died. This signal was used as a cue for intervention in three rats; two survived. Thus, in this preparation, the BAER provided a useful measure of CPR effectiveness, in time to permit successful intervention.


Asunto(s)
Reanimación Cardiopulmonar , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Paro Cardíaco/terapia , Animales , Enfermedades del Sistema Nervioso Central/etiología , Paro Cardíaco/mortalidad , Paro Cardíaco/fisiopatología , Masculino , Monitoreo Fisiológico , Valor Predictivo de las Pruebas , Ratas , Resultado del Tratamiento
17.
Phytopathology ; 91(2): 173-80, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18944391

RESUMEN

ABSTRACT Agrobacterium tumefaciens-mediated transformation (ATMT) has long been used to transfer genes to a wide variety of plants and has also served as an efficient tool for insertional mutagenesis. In this paper, we report the construction of four novel binary vectors for fungal transformation and the optimization of an ATMT protocol for insertional mutagenesis, which permits an efficient genetic manipulation of Fusarium oxysporum and other phytopathogenic fungi to be achieved. Employing the binary vectors, carrying the bacterial hygromycin B phosphotrans-ferase gene (hph) under the control of the Aspergillus nidulans trpC promoter as a selectable marker, led to the production of 300 to 500 hygromycin B resistant transformants per 1 x 10(6) conidia of F. oxysporum, which is at least an order of magnitude higher than that previously accomplished. Transformation efficiency correlated strongly with the duration of cocultivation of fungal spores with Agrobacterium tumefaciens cells and significantly with the number of Agrobacteruium tumefaciens cells present during the cocultivation period (r = 0.996; n = 3; P < 0.01). All transformants tested remained mitotically stable, maintaining their hygromycin B resistance. Growing Agrobacterium tumefaciens cells in the presence of acetosyringone (AS) prior to cocultivation shortened the time required for the formation of transformants but decreased to 53% the percentage of transformants containing a single T-DNA insert per genome. This increased to over 80% when Agrobacterium tumefaciens cells grown in the absence of AS were used. There was no correlation between the average copy number of T-DNA per genome and the colony diameter of the transformants, the period of cocultivation or the quantity of Agrobacterium tumefaciens cells present during cocultivation. To isolate the host sequences flanking the inserted T-DNA, we employed a modified thermal asymmetric interlaced PCR (TAIL-PCR) technique. Utilizing just one arbitrary primer resulted in the successful amplification of desired products in 90% of those transformants analyzed. The insertion event appeared to be a random process with truncation of the inserted T-DNA, ranging from 1 to 14 bp in size, occurring on both the right and left border sequences. Considering the size and design of the vectors described here, coupled with the efficiency and flexibility of this ATMT protocol, it is suggested that ATMT should be regarded as a highly efficient alternative to other DNA transfer procedures in characterizing those genes important for the pathogenicity of F. oxysporum and potentially those of other fungal pathogens.

18.
J Exp Anal Behav ; 37(2): 323-7, 1982 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16812271

RESUMEN

In a review of 103 sets of data from 23 different studies of choice, Baum (1979) concluded that whereas undermatching was most commonly observed for responses, the time measure generally conformed to the matching relation. A reexamination of the evidence presented by Baum concludes that undermatching is the most commonly observed finding for both measures. Use of the coefficient of determination by both Baum (1979) and de Villiers (1977) for assessing when matching occurs is criticized on statistical grounds. An alternative to the loss-in-predictability criterion used by Baum (1979) is proposed. This alternative statistic has a simple operational meaning and is related to the usual F-ratio test. It can therefore be used as a formal test of the hypothesis that matching occurs. Baum (1979) also suggests that slope values of between .90 and 1.11 can be considered good approximations to matching. It is argued that the establishment of a fixed interval as a criterion for determining when matching occurs, is inappropriate. A confidence interval based on the data from any given experiment is suggested as a more useful method of assessment.

19.
Vet Rec ; 129(4): 70-3, 1991 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-1926712

RESUMEN

Greyhounds are usually transported by air between Ireland and England in wooden kennels similar in size to greyhound racing starting traps. These kennels have been criticised in the belief that their small size leads to unnecessary stress. The present study compared plasma ACTH, cortisol, lactate and non-esterified fatty acid concentrations in 12 greyhounds transported either in the existing wooden kennels or in wider perspex kennels, which were stowed either in the belly hold or in the main cargo hold of jet freighter aircraft. Increased kennel size did not appear to result in decreased stress responses but there was a significantly greater stress response in the dogs kept in the belly hold of the aircraft. Individual variation between dogs was the most significant feature of the study.


Asunto(s)
Aeronaves , Enfermedades de los Perros/etiología , Vivienda para Animales , Estrés Fisiológico/veterinaria , Análisis de Varianza , Animales , Cruzamiento , Frío , Perros , Masculino , Estrés Fisiológico/etiología
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