RESUMEN
Diet manipulation and genetic selection are two important mitigation strategies for reducing enteric methane (CH4) emissions from ruminant livestock. The aim of this study was to assess whether the diurnal pattern of CH4 emissions from individual dairy cows changes over time when cows are fed on diets varying in forage composition. Emissions of CH4 from 36 cows were measured during milking in an automatic (robotic) milking station in three consecutive feeding periods, for a total of 84 days. In Periods 1 and 2, the 36 cows were fed a high-forage partial mixed ration (PMR) containing 75% forage, with either a high grass silage or high maize silage content. In Period 3, cows were fed a commercial PMR containing 69% forage. Cows were offered PMR ad libitum plus concentrates during milking and CH4 emitted by individual cows was sampled during 8662 milkings. A linear mixed model was used to assess differences among cows, feeding periods and time of day. Considerable variation was observed among cows in daily mean and diurnal patterns of CH4 emissions. On average, cows produced less CH4 when fed on the commercial PMR in feeding Period 3 than when the same cows were fed on high-forage diets in feeding Periods 1 and 2. The average diurnal pattern for CH4 emissions did not significantly change between feeding periods and as lactation progressed. Emissions of CH4 were positively associated with dry matter (DM) intake and forage DM intake. It is concluded that if the management of feed allocation remains constant then the diurnal pattern of CH4 emissions from dairy cows will not necessarily alter over time. A change in diet composition may bring about an increase or decrease in absolute emissions over a 24-h period without significantly changing the diurnal pattern unless management of feed allocation changes. These findings are important for CH4 monitoring techniques that involve taking measurements over short periods within a day rather than complete 24-h observations.
RESUMEN
OBJECTIVE: To evaluate asphyxial patterns in term encephalopathic newborns caused by chorioamnionitis or intrapartum blood loss that resulted in cerebral palsy and allegations of obstetrical professional liability. STUDY DESIGN: As an expert witness, JKM identified term newborns with profound neurologic impairment: 18 born in the presence of chorioamnionitis and 14 with significant anemia. RESULT: In both study groups, profound depression with low 10-min Apgars was associated with early-onset seizures (88%), multiorgan failure (94%) and a partial prolonged injury to the cortex and subcortical white matter (94%). A cord arterial pH>7.00 was noted in 68% and deep gray matter injury involving the basal ganglia and thalamus occurred in only 19% of the newborns studied. CONCLUSION: The cord arterial pH and pCO2 values, early-onset seizures and paucity of isolated deep gray matter injury support that significant injury occurred postnatally despite appropriate resuscitation. This unique pattern may refute allegations of obstetrical mismanagement in the intrapartum period.
Asunto(s)
Anemia Neonatal , Parálisis Cerebral , Corioamnionitis/diagnóstico , Hipoxia-Isquemia Encefálica , Síndrome de Respuesta Inflamatoria Sistémica , Hemorragia Uterina , Adulto , Anemia Neonatal/diagnóstico , Anemia Neonatal/etiología , Puntaje de Apgar , Dióxido de Carbono/análisis , Parálisis Cerebral/diagnóstico , Parálisis Cerebral/etiología , Cordocentesis/métodos , Femenino , Enfermedades Fetales/diagnóstico , Enfermedades Fetales/etiología , Humanos , Concentración de Iones de Hidrógeno , Hipoxia-Isquemia Encefálica/diagnóstico , Hipoxia-Isquemia Encefálica/etiología , Recién Nacido , Enfermedades del Recién Nacido/diagnóstico , Enfermedades del Recién Nacido/etiología , Complicaciones del Trabajo de Parto/diagnóstico , Obstetricia/legislación & jurisprudencia , Embarazo , Estadística como Asunto , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Nacimiento a Término , Estados Unidos , Hemorragia Uterina/complicaciones , Hemorragia Uterina/diagnósticoRESUMEN
The aims of this study were to compare methods for examining measurements of CH4 and CO2 emissions of dairy cows during milking and to assess repeatability and variation of CH4 emissions among individual dairy cows. Measurements of CH4 and CO2 emissions from 36 cows were collected in 3 consecutive feeding periods. In the first period, cows were fed a commercial partial mixed ration (PMR) containing 69% forage. In the second and third periods, the same 36 cows were fed a high-forage PMR ration containing 75% forage, with either a high grass silage or high maize silage content. Emissions of CH4 during each milking were examined using 2 methods. First, peaks in CH4 concentration due to eructations during milking were quantified. Second, ratios of CH4 and CO2 average concentrations during milking were calculated. A linear mixed model was used to assess differences between PMR. Variation in CH4 emissions was observed among cows after adjusting for effects of lactation number, week of lactation, diet, individual cow, and feeding period, with coefficients of variation estimated from variance components ranging from 11 to 14% across diets and methods of quantifying emissions. No significant difference was detected between the 3 PMR in CH4 emissions estimated by either method. Emissions of CH4 calculated from eructation peaks or as CH4 to CO2 ratio were positively associated with forage dry matter intake. Ranking of cows according to CH4 emissions on different diets was correlated for both methods, although rank correlations and repeatability were greater for CH4 concentration from eructation peaks than for CH4-to-CO2 ratio. We conclude that quantifying enteric CH4 emissions either using eructation peaks in concentration or as CH4-to-CO2 ratio can provide highly repeatable phenotypes for ranking cows on CH4 output.
Asunto(s)
Dióxido de Carbono/metabolismo , Eructación/metabolismo , Lactancia , Metano/metabolismo , Ensilaje/análisis , Animales , Bovinos , Dieta/veterinaria , Eructación/veterinaria , Femenino , Leche/química , Zea mays/químicaRESUMEN
Methane (CH4) emissions by dairy cows vary with feed intake and diet composition. Even when fed on the same diet at the same intake, however, variation between cows in CH4 emissions can be substantial. The extent of variation in CH4 emissions among dairy cows on commercial farms is unknown, but developments in methodology now permit quantification of CH4 emissions by individual cows under commercial conditions. The aim of this research was to assess variation among cows in emissions of eructed CH4 during milking on commercial dairy farms. Enteric CH4 emissions from 1964 individual cows across 21 farms were measured for at least 7 days/cow using CH4 analysers at robotic milking stations. Cows were predominantly of Holstein Friesian breed and remained on the same feeding systems during sampling. Effects of explanatory variables on average CH4 emissions per individual cow were assessed by fitting a linear mixed model. Significant effects were found for week of lactation, daily milk yield and farm. The effect of milk yield on CH4 emissions varied among farms. Considerable variation in CH4 emissions was observed among cows after adjusting for fixed and random effects, with the CV ranging from 22% to 67% within farms. This study confirms that enteric CH4 emissions vary among cows on commercial farms, suggesting that there is considerable scope for selecting individual cows and management systems with reduced emissions.
Asunto(s)
Bovinos/fisiología , Tracto Gastrointestinal/metabolismo , Lactancia/fisiología , Metano/metabolismo , Animales , Industria Lechera , Eructación/metabolismo , Eructación/veterinaria , Femenino , Flatulencia/metabolismo , Flatulencia/veterinaria , Metano/análisis , Leche/metabolismoAsunto(s)
Células/ultraestructura , Ingenio y Humor como Asunto , Animales , Humanos , Microscopía ElectrónicaAsunto(s)
Química/historia , Historia del Siglo XX , Fisiología/historia , Estados Unidos , WashingtónRESUMEN
AIMS: The ability to predict the morbidity of retained deciduous teeth with no permanent successors, a characteristic of hypodontia, would be of considerable value in treatment planning, but is hampered by lack of data. METHODS: This problem was studied using 356 orthopantomogram radiographs (OPGs) from the records of 249 patients who had attended a specialist hypodontia clinic, and had retained deciduous teeth with no permanent successors. Due to their clinical importance, canine and molar teeth were chosen for examination. Resorption was assessed subjectively by three experienced clinicians. RESULTS: Un-weighted Kappa values for reproducibility were > 0.8, and for interobserver error 0.60-0.83. Gender related differences were minimal. Regardless of gender or radiographic age, the lower canines appear to show the least amount of resorption and the upper first molars the most. The upper and lower second molars have particularly unpredictable life spans. Whilst the lower first molars have a predictable life span that is poor, the life span for the upper first molars is slightly worse. CONCLUSIONS: Lower canines have a predictable life span that appears to be good, as do upper canines, but of lesser duration than lower canines. Molars have poorer and less predictable life spans.
Asunto(s)
Anodoncia/diagnóstico por imagen , Diente Canino/diagnóstico por imagen , Diente Molar/diagnóstico por imagen , Resorción Radicular/diagnóstico por imagen , Diente Primario/diagnóstico por imagen , Adolescente , Adulto , Factores de Edad , Niño , Diente Canino/anomalías , Femenino , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Diente Molar/anomalías , Variaciones Dependientes del Observador , Pronóstico , Radiografía Panorámica , Reproducibilidad de los Resultados , Estudios Retrospectivos , Resorción Radicular/clasificación , Factores Sexuales , Estadística como AsuntoRESUMEN
In the human pregnant state a high molecular weight form of angiotensinogen (HMrA) is present in significant quantities in addition to the usual low molecular weight angiotensinogen (LMrA). In a previous study involving a small number of white women, it was found that women who had developed pregnancy-induced hypertension (PIH) had significantly higher levels of plasma HMrA. It has been determined that there are five isoforms of HMrA. The objectives of this study were to expand the previous study with the inclusion of black women and to determine which isoform(s) of plasma HMrA are elevated in PIH. Plasma LMrA and HMrA were quantitated in 24 normotensive pregnant women and 65 women with PIH. The PIH group had higher levels of HMrA and somewhat lower levels of LMrA than the normotensive group. The HMrA/LMrA ratio was elevated in 47% of the PIH group. The five isoforms of HMrA were quantitated in plasma from 10 white women with PIH, 10 black women with PIH, and 6 normotensive pregnant white women. Half of both the white and black women with PIH had an elevated HMrA/LMrA ratio. The relative proportion of the HMrA isomers was similar in all groups. These studies show that half the women with PIH have a distinct abnormality in their renin angiotensin system. Both white and black women show this abnormality. In those women who have an elevated total HMrA, all five isoforms of HMrA are equally elevated.
Asunto(s)
Angiotensinógeno/sangre , Hipertensión/sangre , Complicaciones Cardiovasculares del Embarazo/sangre , Angiotensinógeno/química , Población Negra , Estudios de Cohortes , Femenino , Humanos , Peso Molecular , Embarazo , Isoformas de Proteínas/sangre , Población BlancaRESUMEN
Incontinentia Pigmenti (Bloch-Sulzberger syndrome) is an uncommon genodermatosis that usually affects female infants. The condition is characterized by four cutaneous stages and is frequently associated with dental, ocular, central nervous system and structural anomalies. A large case series of seven patients, all female, who presented to the Department of Paediatric Dentistry at the Eastman Dental Hospital over the last 16 years is reported. The dental features of these cases were typical and included missing teeth, microdontia and delayed eruption. In two of the seven cases, both maxillary canines were palatally impacted.
Asunto(s)
Incontinencia Pigmentaria/complicaciones , Anomalías Dentarias/etiología , Anodoncia/etiología , Niño , Preescolar , Femenino , Humanos , Lactante , Odontometría , Anomalías Dentarias/patología , Erupción DentalRESUMEN
Heat and moisture exchangers (HMEs) have been used for more than 30 years for heat and moisture retention during general anesthesia. Studies about bacteriostatic vs nonbacteriostatic HMEs (BHMEs/NHMEs) have been conducted to assess their role in preventing bacterial transmission to the anesthesia breathing circuit; none have been done on anesthetized patients in the operating room. The present study adds to existing knowledge about the HME's ability to prevent transmission of bacteria, with implications for cost reduction resulting from reuse of anesthesia breathing circuits among patients. The chi 2 test revealed no statistically significant differences between groups in transmission of bacteria from endotracheal tube (ETT) to anesthesia breathing circuit (P = .48). However, both groups showed statistically significant differences between presence of bacteria in ETTs and anesthesia breathing circuits: Group 1, BHME (P < .005) and group 2, NHME (P < .005). Neither HME prevented contamination of the machine side of the circuit. These results support not reusing breathing circuits. Of 53 participants in group 2, 28 had positive ETT cultures with 7 showing transmission to anesthesia breathing circuit. Of 46 participants in group 1, 28 had positive ETT cultures with 9 showing transmission to anesthesia breathing circuit.
Asunto(s)
Anestesiología/instrumentación , Infecciones Bacterianas/etiología , Infección Hospitalaria/etiología , Contaminación de Equipos , Equipo Reutilizado , Calor , Nebulizadores y Vaporizadores , Anestesiología/economía , Infecciones Bacterianas/prevención & control , Infecciones Bacterianas/transmisión , Control de Costos , Infección Hospitalaria/prevención & control , Infección Hospitalaria/transmisión , Contaminación de Equipos/economía , Contaminación de Equipos/prevención & control , Equipo Reutilizado/economía , Calor/uso terapéutico , Humanos , Control de Infecciones/métodos , Nebulizadores y Vaporizadores/economía , Enfermeras Anestesistas , Proyectos PilotoRESUMEN
OBJECTIVE: To review a series of cases of hypophosphataemic vitamin D resistant rickets. SUBJECTS INCLUDED: Seventeen cases, aged between 2 years 1 month and 15 years 9 months at first referral, and with an established diagnosis of vitamin D resistant rickets from twelve families were included in the review. Information was drawn from patient records for follow-up periods between 9 months and 20 years 4 months. SETTING: All subjects had been referred to the Eastman Dental Hospital between 1973 and 1997. FINDINGS: Abscessed non-carious primary and/or permanent teeth were a presenting feature in eleven of the seventeen cases. Although attrition and exposure of the abnormally formed dentine accounted for the route of infection in primary teeth, the route for microbial invasion of pulpal tissues in permanent teeth remained unexplained in a number of patients. The possible part played by infractures of the enamel as a portal of entry for infection is discussed. Enamel defects were observed in only six patients, in three of whom these changes were limited to the primary dentition. Taurodontism of permanent molar teeth was confirmed as a feature of the condition in the more severely affected male subjects.
Asunto(s)
Absceso/etiología , Enfermedades de la Pulpa Dental/etiología , Hipofosfatemia Familiar/complicaciones , Enfermedades Dentales/etiología , Absceso/diagnóstico por imagen , Adolescente , Niño , Preescolar , Esmalte Dental/diagnóstico por imagen , Cavidad Pulpar/anomalías , Cavidad Pulpar/diagnóstico por imagen , Enfermedades de la Pulpa Dental/diagnóstico por imagen , Dentina/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Hipofosfatemia Familiar/diagnóstico por imagen , Masculino , Radiografía , Enfermedades Dentales/diagnóstico por imagenRESUMEN
Mycobacterium avium is an intracellular pathogen that is associated with disseminated infection in acquired immunodeficiency syndrome (AIDS). Patients with AIDS appear to acquire M. avium mainly through the gastrointestinal tract. Previous studies have shown that healthy mice given M. avium orally develop disseminated infection after 2-4 weeks. The chief site of M. avium invasion of the intestinal mucosa is the terminal ileum. To learn more about the pathophysiology of M. avium infection of the intestinal mucosa, C57BL/6 bg+ bg+ mice were infected orally with M. avium strain 101 and groups of six mice were killed each week for 8 weeks. The terminal ileum was then prepared for histopathological studies and electron microscopy. A delayed inflammatory response was observed and influx of neutrophils in the Peyer's patches was the only abnormality seen at 1 week. A severe inflammatory response was seen from week 2 to week 5 and necrosis of intestinal villi was observed 6 weeks after infection. These results indicate that invasion and infection of the normal intestine by M. avium results in a severe inflammatory response with segmental necrosis of the intestinal mucosa.
Asunto(s)
Ileítis/microbiología , Íleon/microbiología , Mucosa Intestinal/microbiología , Complejo Mycobacterium avium/patogenicidad , Infección por Mycobacterium avium-intracellulare/microbiología , Animales , Femenino , Ileítis/patología , Íleon/patología , Íleon/ultraestructura , Mucosa Intestinal/patología , Mucosa Intestinal/ultraestructura , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Infección por Mycobacterium avium-intracellulare/patología , Necrosis , Ganglios Linfáticos Agregados/microbiología , Ganglios Linfáticos Agregados/patología , Ganglios Linfáticos Agregados/ultraestructuraRESUMEN
Infections caused by organisms of the Mycobacterium avium complex occur in approximately 50 to 60% of patients with AIDS. M. avium is an intracellular pathogen that survives and multiplies within mononuclear phagocytes. In this study, we investigated the uptake of M. avium grown within macrophages (intracellular growth M. avium [IG]) by a second macrophage compared with M. avium cultured in broth (extracellular growth M. avium [EG]). The results showed that IG was six- to eightfold more efficient than EG in entering macrophages. In addition, while an anti-CR3 antibody was able to inhibit approximately 60% of EG uptake by macrophages, it failed to inhibit the entry of IG. In contrast to EG, IG uptake into macrophages was significantly inhibited in the presence of anti-beta1-integrin and anti-transferrin receptor antibodies. Entry into macrophages by alternate receptors was associated with resistance to tumor necrosis factor alpha (TNF-alpha) stimulation. While stimulation with TNF-alpha resulted in inhibition of the growth of EG, it was not associated with inhibition of intracellular growth of IG. Investigation of the reason why M. avium is able to sense the changes in the intracellular environment triggering a change to the invasive phenotype suggests a direct relationship with macrophage apoptosis. These results suggest that intracellular growth is associated with novel mechanisms of M. avium uptake of macrophages and that those mechanisms appear to offer advantages to the bacteria in escaping the host defense.
Asunto(s)
Macrófagos/microbiología , Complejo Mycobacterium avium/crecimiento & desarrollo , Infección por Mycobacterium avium-intracellulare/microbiología , Anticuerpos Bloqueadores/inmunología , Apoptosis/inmunología , Catalasa/farmacología , Medios de Cultivo , Fragmentación del ADN , Sulfato de Dextran/farmacología , Heparina/farmacología , Humanos , Integrina beta1/inmunología , Antígeno de Macrófago-1/inmunología , Microscopía Electrónica , Complejo Mycobacterium avium/inmunología , Complejo Mycobacterium avium/ultraestructura , Infección por Mycobacterium avium-intracellulare/inmunología , Fagocitosis/inmunología , Polisacáridos/farmacología , Receptores de Transferrina/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
Retrospective analysis of 28 children suffering from severe infra-occlusion and/or primary failure of eruption of deciduous molars revealed an association with eruptive and developmental disturbances in the permanent dentition, including ectopically placed teeth and aplasia of teeth. Taurodont permanent molars were evident in 19 of the 28 selected cases which suggests a possible developmental relationship between these factors. Problems in relation to treatment of these cases are discussed.
Asunto(s)
Maloclusión/etiología , Diente Molar/anomalías , Anomalías Dentarias/complicaciones , Erupción Ectópica de Dientes/complicaciones , Diente no Erupcionado/complicaciones , Adolescente , Niño , Preescolar , Dentición Permanente , Femenino , Humanos , Masculino , Maloclusión/genética , Linaje , Estudios Retrospectivos , Anomalías Dentarias/genética , Erupción Ectópica de Dientes/genética , Diente Primario , Diente no Erupcionado/genética , Dimensión VerticalRESUMEN
Toxoplasmosis is a parasitic infection which may be asymptomatic or produce lymphadenopathy, fever and malaise. In children the cervical lymph nodes are most commonly affected. This report describes a case of a 9-year-old boy who presented with submandibular lymphadenopathy associated with a non-vital primary tooth, which persisted following extraction of the tooth. A diagnosis of acquired toxoplasmosis was made on the findings of fine-needle aspiration cytology and subsequently confirmed by serological investigations, thus sparing the patient unnecessary hospitalization and surgery. The patient required amitryptyline as a nocturnal sedative and made a complete recovery within a few months without the need for further intervention.
Asunto(s)
Ganglios Linfáticos/parasitología , Enfermedades Linfáticas/parasitología , Toxoplasmosis , Toxoplasmosis/diagnóstico , Biopsia con Aguja , Niño , Diagnóstico Diferencial , Ensayo de Inmunoadsorción Enzimática , Humanos , Enfermedades Linfáticas/diagnóstico , Masculino , Cuello , Diente no Vital , Toxoplasmosis/patologíaRESUMEN
A case of trisomy for the short arm of chromosome 9 in a 13-year-old boy is described. Particular emphasis is placed upon a number of abnormal dental findings, which include enamel hypoplasia, hypodontia, and severe dental crowding. The difficulties of providing comprehensive dental treatment in cases such as these is discussed.
Asunto(s)
Anodoncia/patología , Cromosomas Humanos Par 9 , Hipoplasia del Esmalte Dental/patología , Maloclusión/patología , Trisomía , Adolescente , Atención Odontológica Integral , Caries Dental/patología , Gingivitis/patología , Humanos , Masculino , Atrición Dental/patología , Fracturas de los Dientes/patologíaRESUMEN
Band 3 performs the same structural and functional activities in adult brain as it does in erythrocytes. It ages as cells and tissues age Our studies, to date, indicate that the anion transport ability of band 3 decreases in brains and lymphocytes from old mice. This decreased transport ability precedes obvious structural changes, such as band 3 degradation and generation of SCA and is the earliest change thus far detected in band 3. The following changes occur in lymphocytes, erythrocytes and brain band 3 with aging: 1) a decreased efficiency of anion transport (decreased Vmax) in spite of an increase in number of anion binding sites (increased K(m)), 2) a decreased glucose transport, 3) 32P labeling in vitro, 4) an increased degradation to smaller fragments as detected by quantitative binding of antibodies to band 3 breakdown products and residue 812-830, and 5) a binding of physiologic IgG autoantibodies in situ. The latter three findings indicate that posttranslational changes occur. In addition, the anion transporter, band 3, undergoes an as yet undefined change that results in binding of "980" antibodies to aged band 3. Posttranslational changes in AD include decreased brain and RBC phosphorylation of a M(r) = 135, 113 and 45 kDa band 3 polypeptides due to the phosphorylation site being already occupied, increased degradation of band 3, alterations in band 3 recognized by antibodies, and decreased anion and glucose transport by blood cells. Band 3 in erythrocytes of AD patients has a different immunological identity from normal band 3 as evidenced by the binding of antibodies described in this study. AD may be preferentially manifested in the brain because neurons accumulate damage throughout the lifetime as they do not regenerate or undergo cell division. We suspect, and our data indicate, that the same mechanism(s) of AD occurs in all cells, but that the manifestations differ due to different cell proteins and functions.
Asunto(s)
Envejecimiento/metabolismo , Enfermedad de Alzheimer/metabolismo , Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Encéfalo/metabolismo , Envejecimiento Eritrocítico , Procesamiento Proteico-Postraduccional , Enfermedad de Alzheimer/sangre , Secuencia de Aminoácidos , Animales , Antioxidantes/farmacología , Eritrocitos/metabolismo , Femenino , Glucosa/metabolismo , Humanos , Transporte Iónico , Linfocitos/metabolismo , Ratones , Ratones Endogámicos CBA , Datos de Secuencia Molecular , Oxidación-Reducción , FosforilaciónRESUMEN
The management of severe lack of teeth in the dental arch presents the clinician with a number of difficulties. In this paper, the second in a series on hypodontia, the problems are outlined and suggestions made as how best to overcome them.