Seroprevalence of Coxiella burnetii antibodies in wild deer populations in eastern Australia.

Coxiella burnetii causes significant reproduction losses in livestock and the disease Q fever in humans. Transmission of C. burnetii is facilitated by the stability of the bacterium in the environment and the susceptibility of a variety of host species to infection. Consequently, inter-species transmission occurs frequently through either direct or indirect contact. Wildlife may represent reservoirs of C. burnetii and could therefore be a source of infection for domestic animals. Understanding the prevalence of C. burnetii infections at the wildlife-livestock interface is important for disease control. This study aimed to investigate the extent of C. burnetii exposure in wild deer in eastern Australia. Serum samples were obtained from 413 wild deer from seven regions in four eastern Australian states from 2017 to 2020. Antibodies were detected using a commercial Q fever antibody kit validated for ruminants. Seroprevalence of C. burnetii antibodies in deer was determined and true prevalence estimated, for each region. The overall seroprevalence of C. burnetii antibodies in wild deer was 3.4% (14 seropositive of 413 deer sampled) with true prevalence estimated to be 4.3% (95% credible interval: 0.6%, 10.9%). Seropositive deer were identified only in Queensland (7/108 seropositive) and northern New South Wales (7/120 seropositive). This geospatial distribution is consistent with seropositivity in other animal species and indicative of the level of C. burnetii in the environment. The low seroprevalence suggests that wild deer are unlikely to be a major reservoir species for C. burnetii in eastern Australia but may still be implicated in inter-species transmission cycles.

Caregivers' knowledge and perceptions are associated with children's TB preventive treatment completion.

SETTING: Forty-six health centers in south Lima, Peru. OBJECTIVE: To assess the association between caregivers' knowledge and perceptions around isoniazid preventive therapy (IPT) and whether their children complete IPT. DESIGN: We conducted a retrospective medical record review of children who initiated IPT during 2017-2018. We administered structured surveys to caregivers of the children about their knowledge about and perceptions of IPT. We used a modified Poisson regression to determine factors associated with IPT completion. RESULTS: We included 550 children, of whom 31% did not complete IPT. Independent factors associated with not completing IPT were low caregiver knowledge about TB and IPT (adjusted risk ratio [aRR] 1.41, 95% CI 1.06-1.78), low caregiver perception of the importance of IPT (aRR 1.76, 95% CI 1.30-2.39), low caregiver satisfaction with the health services (aRR 1.57, 95% CI 1.14-2.16), experience of adverse events (aRR 2.08, 95% CI 1.51-2.87), and living in a household with moderate or severe family dysfunction (aRR 1.53, 95% CI 1.07-2.19). CONCLUSION: IPT completion among children was associated with the knowledge and perceptions of their caregivers, as well as the experience of adverse events. To improve IPT completion among children, health care providers should prioritize education and counseling for caregivers, promote positive interpersonal relationships with them, and monitor adverse events.

CONTEXTE: Quarante-six centres de santé au Sud de Lima, Pérou. OBJECTIF: Evaluer l'association entre les connaissances et les perceptions relatives au traitement préventif par l'isoniazide (TPI) des responsables des enfants et le fait que leurs enfants aient achevé le TPI. SCHÉMA: Nous avons réalisé une revue rétrospective des dossiers médicaux des enfants qui ont démarré le TPI entre 2017 et 2018. Nous avons administré aux responsables des enfants des questionnaires structurés relatifs à leurs connaissances et perceptions du TPI. Nous avons utilisé une régression de Poisson modifiée afin de déterminer les facteurs associés à l'achèvement du TPI. RÉSULTATS: Nous avons inclus 500 enfants dont 31% n'ont pas achevé le TPI. Les facteurs indépendants associés au non achèvement étaient faibles connaissances relatives à la TB et au TPI (risque relatif ajusté [RRa] 1,41 ; IC 95% 1,06­1,78), faibles perception par les responsables de l'importance du TPI (RRa 1,76 ; IC 95% 1,30­2,39), faible taux de satisfaction des responsables par rapport aux services de santé (RRa 1,57 ; IC 95% 1,14­2,16), survenue d'effets secondaires (RR 2,08 ; IC 95% 1,51­2,87) et dysfonction familiale modérée ou grave (RRa 1,53 ; IC 95% 1,07­2,19). CONCLUSION: L'achèvement du TPI chez les enfants a été associé aux connaissances et perceptions de leurs responsables, ainsi qu'à la survenue d'effets secondaires. Pour améliorer l'achèvement du TPI chez les enfants, les prestataires de soins de santé devraient accorder la priorité à l'éducation des responsables, promouvoir des relations inter personnelles positives avec eux et surveiller les effets secondaires.

Higroma quístico retronucal como marcador de anomalías cromosómicas en el primer trimestre de la gestación / Retronuchal cystic hygroma in the first trimester of pregnancy as a marker of chromosomal abnormalities

Background: Nuchal cystic hygroma is the most frequently identified marker of chromosomal anomalies during first trimester screening. Objective: To determine the association of the nuchal cystic hygroma with chromosomal anomalies diagnosed with karyotyping done between the first and second trimesters of pregnancy. Design: Retrospective study. Setting: Instituto Latinoamericano de Salud Reproductiva (ILSAR), Lima, Peru. Patients. Fetuses with nuchal cystic hygroma. Methods: The data were obtained from the ILSAR database between August 2007 and May 2018, the cases diagnosed by ultrasound from week 11 to 13.6. Nuchal cystic hygroma was defined as the presence of septated liquid content in the nuchal axial section with a thickness above the 95th percentile value for increased nuchal translucency value for the crown-rump length. The karyotype was obtained between the first and second trimesters from material collected by chorionic villus sampling (BVS) or amniocentesis (AMC). Main outcome measures: Karyotyping results were compared between cases with cystic hygroma alone and cases with cystic hygroma in addition to another marker. Results: Out of 459 invasive procedures performed in fetuses with high risk for chromosomal anomalies based on the Fetal test database of Spain, there were 162 cases of chromosomal anomalies (35.3%), and 104 cases of nuchal cystic hygroma (22.7%). Nuchal cystic hygroma was associated with a higher frequency of chromosomal abnormalities, compared to fetuses without cystic hygroma (52.9% vs. 30.1%; p<0.001). Out of 61 cases of hygroma alone, 42.3% had chromosomal anomalies, and when the hygroma was associated with other markers (fetal hydrops, abnormal ductus venosus, heart disease), 65.1% had chromosomal abnormalities. There was a statistically significant difference (p=0.003) for the presence of monosomy X between the group with cystic hygroma alone and the group with hygroma and fetal hydrops. There was no difference in hygroma thickness between the groups with and without chromosomal abnormalities. Conclusions: Nuchal cystic hygroma is a risk marker with high predictive value for chromosomal abnormalities, and its identification during prenatal screening may be considered an indication to a diagnostic test. When cystic hygroma is associated to flow abnormalities of the ductus venosus or fetal hydrops, chromosomal abnormalities significantly increase. The hygroma associated with hydrops was primarily linked to monosomy X, while the hygroma associated with abnormal flow velocity waveforms of the ductus venosus was linked to trisomy 21.

Antecedentes. El higroma quístico retronucal es el marcador de anomalías cromosómicas identificado con mayor frecuencia en el tamizaje del primer trimestre. Objetivo. Evaluar la asociación del higroma quístico retronucal y anomalías cromosómicas diagnosticadas con el cariotipo, entre el primer y segundo trimestre del embarazo. Diseño. Estudio retrospectivo. Institución. Instituto Latinoamericano de Salud Reproductiva (ILSAR), Lima, Perú. Pacientes. Fetos con higroma quístico retronucal. Método. Estudio de fetos con higroma quístico retronucal, obtenidos de la base de datos de ILSAR, entre agosto del 2007 y mayo del 2018, diagnosticados por ecografía entre las 11 y 13,6 semanas. El higroma quístico retronucal se definió como la presencia de contenido líquido tabicado en el corte axial retronucal con un grosor mayor al percentil 95 del valor de translucencia nucal aumentada para la longitud corona-nalga. Se obtuvo el cariotipo entre el primer y segundo trimestre en material obtenido por biopsia de vellosidades coriales (BVC) o amniocentesis (AMC). Principales medidas de resultados. Los resultados del cariotipo fueron comparados entre los casos de higroma quístico solo y los casos que tuvieron higroma y adicionalmente otro marcador. Resultados. De un total de 459 procedimientos invasivos realizados en fetos con alto riesgo para anomalías cromosómicas en base al Fetal test de España, hubieron 162 casos de anomalías cromosómicas (35,3%) y se identificó 104 casos de higroma quístico retronucal (22s7%). El hallazgo de higroma quístico retronucal se asoció con mayor presencia de anomalías cromosómicas, comparado con los fetos sin higroma quístico (52,9% vs. 30,1%; p<0,001). De 61 casos de higroma solo, 42,3% tenían anomalía cromosómica, y cuando el higroma estaba asociado a otros marcadores (hidrops fetal, ductus venoso anormal, cardiopatía, ausencia de hueso nasal), hubo 65,1% de anomalías cromosómicas. Hubo diferencia estadística significativa (p=0,003) para la presencia de monosomía X, entre el grupo con higroma solo y el de higroma + hidrops fetal. No hubo diferencia en el grosor del higroma entre el grupo con y sin anomalía cromosómica. Conclusiones. El higroma quístico retronucal es un marcador de riesgo con alto valor predictivo para anomalías cromosómicas. Su identificación en el tamizaje prenatal podría ser indicación para recomendar una prueba diagnóstica. Cuando se asocia a anormalidad del flujo del ductus venoso o hidrops fetal, aumentan significativamente las anomalías cromosómicas. El higroma asociado con hidrops se vinculó mayoritariamente a la monosomía X, mientras que el higroma asociado con onda de velocidad de flujo-OVF de ductus venoso anormal a la trisomía 21.

Uso de la sugestión en el manejo de la conducta del niño en odontología pediátrica / Use of suggestion in behavior management children in pediatric dentistry

La sugestión siempre ha sido utilizada por los seres humanos en otros seres humanos, tanto de forma consciente como inconsciente. Desde que la humanidad comenzó a ser consciente de si, comenzaron los intentos para influir en los demás. En la práctica clínica, muchos odontopediatras usan la sugestión de forma intuitiva en el manejo de la conducta del paciente. El objetivo de este articulo hacer una revisión bibliográfica sobre el uso de la sugestión en odontopediatria, los tipos de sugestión y algunas técnicas de sugestión usadas en el manejo de la conducta del niño...

The suggestion has always been used by humans over other human beings, both consciously and unconsciously. Since mankind began to be conscious of itself, began attempts to influence others. In clinical practice many pediatric dentists use intuitively suggestion in the management of the patient's behavior. The aim of this paper to review the literature on the use of suggestion in pediatric dentistry, types of suggestion and some suggestion techniques used in managing children's behavior...

Formation of Pt decorated Ni-Pt nanocubes through low temperature atomic diffusion--time-resolved elemental analysis of nanoparticle formation.

The formation process of Pt decorated Ni-Pt nanocubes was investigated by analysing the elemental distribution of Ni and Pt in the particles obtained from time-resolved in situ sampling during the synthesis in the oleylamine-1-heptanol system. The analysis confirmed the formation of Pt(core)-Ni(shell) nanoparticles at the initial stages of the reaction. However, as the reaction time progressed, the Pt atoms at the centre diffused outward and reached the corners and edges of the particle, whose shape changed from nearly spherical at the initial stages of the reaction to a perfect cube at the end of the reaction, forming a Ni rich cube (core)-Pt(cage). The cage obtained by dissolving the Ni rich cube was composed mainly of Pt and the Ni content in the frame was a mere 12%. The catalytic activity of the Pt cage was measured using cyclic voltammetry. The initial measurements suggested that the activity was comparable to some of the commercially available Pt catalysts.

Medición de la longitud del cérvix por ecografía abdominal en gestantes normales entre 21 a 23 semanas

Objetivos: Evaluar la factibilidad técnica para medir la longitud del cérvix por ecografía abdominal en gestantes entre 20 y 23 semanas, y la correlación entre los valores obtenidos por ecografía abdominal versus ecografía vaginal. Diseño: Estudio observacional transversal. Lugar: Instituto Latinoamericano de Salud Reproductiva (ILSAR), Lima, Perú. Participantes: Gestantes. Métodos: En 67 gestantes normales sin factores de riesgo para parto pretérmino (PP), entre las 20 y 23 semanas de gestación, se midió la longitud cervical, en 30 de ellas tanto por ecografía abdominal utilizando transductor convexo de 3-5 MHZ como por ecografía vaginal con transductor endocavitario de 5-7 MHZ. Principales medidas de resultados: Correlación de la medida de la longitud del cérvix por ecografía abdominal y transvaginal. Resultados: En 65 gestantes se obtuvo una medida satisfactoria de la longitud del cérvix mediante ecografía abdominal (97% de casos). Se encontró correlación entre las mediciones por ecografía abdominal y vaginal (coeficiente Pearson 0,646, p<0,0001) y no existió diferencia significativa entre ambos valores (p:0,126) para IC del 95%. Conclusiones: En 97% de los casos estudiados se obtuvo una medida satisfactoria de la longitud del cérvix por ecografía abdominal. Hubo correlación, sin diferencia significativa, entre las mediciones obtenidas por vía abdominal y vaginal.

Objectives: To determine the feasibility of cervical length measurement by transabdominal ultrasound at 20-23 weeks of gestation and to correlate this measurements with those obtained by tansvaginal ultrasound. Design: Observational cross-sectional study. Setting: Instituto Latinoamericano de Salud Reproductiva (ILSAR), Lima, Peru. Participants: Pregnant women. Methods: In 67 pregnant women with no risk factors for preterm delivery (PTD) measurement of the uterine cervix at 20-23 weeks of gestation was performed. Thirty women (30) underwent both transabdominal and transvaginal ultrasound measurement. Main outcome measures: Correlation of uterine cervix measurement by abdominal and transvaginal ultrasound. Results: The cervix could be measured satisfactorily by transabdominal measurement in 65 women (97%). There was a good correlation between transabdominal and transvaginal measurement (r<.0.646, p<0.001) and there was no significant difference between both measurements (p:0.126). Conclusions: The uterine cervix could be measured by transabdominal ultrasound in 97% of pregnant women. There was correlation between measurements obtained by transabdominal and transvaginal ultrasound.

Medición de la longitud del cérvix por ecografía abdominal en gestantes normales entre 20 a 23 semanas

Objetivos: Evaluar la factibilidad técnica para medir la longitud del cérvix por ecografía abdominal en gestantes entre 20 y 23 semanas, y la correlación entre los valores obtenidos por ecografía abdominal vs. ecografía vaginal. Diseño: Estudio observacional transversal. Institución: Instituto Latinoamericano de Salud Reproductiva (ILSAR), Lima, Perú. Participantes: Gestantes normales de 20 a 23 semanas de gestación. Métodos: Se midió la longitud cervical por ecografía a 67 gestantes normales sin factores de riesgo para parto pretérmino, entre las 20 y 23 semanas de gestación, con la finalidad de medir la longitud cervical. En 30 de las embarazadas se midió la longitud cervical por ecografía abdominal utilizando transductor convexo de 3-5 MHZ y por ecografía vaginal con transductor endocavitario de 5-7 MHZ. Principales medidas de resultados: Medida de la longitud del cérvix. Resultados: En 65 gestantes se obtuvo una medida satisfactoria de la longitud del cérvix mediante ecografía abdominal (97% de los casos). Se encontró correlación entre las mediciones por ecografía abdominal y vaginal (coeficiente de Pearson 0,646, p<0,001) y no existió diferencia significativa entre ambas mediciones (p: 0,126). Conclusiones: En 97% de los casos estudiados se obtuvo una medida satisfactoria de la longitud del cérvix por ecografía abdominal. Hubo correlación entre las mediciones obtenidas por vía abdominal y vaginal.

Objectives: To assess the feasibility of measuring cervical by transabdominal ultrasound between 20 and 23 weeks of gestation and compare these measurements with those obtained by transvaginal ultrasound. Design: Crosssectional study. Setting: Instituto Latinoamericano de Salud Reproductiva (ILSAR), Lima, Peru. Participants: Normal pregnant women with no risk factors for preterm delivery (PTD). Methods: Cervical length was measured to 67 normal pregnant women 20-23 weeks by transabdominal ultrasound. In 30 women cervical length was measured by abdominal ultrasound using 3-5 MHZ convex transducer and by vaginal ultrasound with 5-7 MHZ endotransducer. Main outcome measures: Cervical length measurement. Results: The cervix was satisfactorily measured by transabdominal ultrasound in 65 women (97%). There was good correlation between transabdominal and transvaginal measurement (r<.0.646, p<0.001) with no significant difference between those measurements (p: 0.126). Conclusions: The cervix could be measured by transabdominal ultrasound in 97% of women. There was correlation between transabdominal and transvaginal ultrasound measurements.

The sensitivity of tropical leaf litter decomposition to temperature: results from a large-scale leaf translocation experiment along an elevation gradient in Peruvian forests.

• We present the results from a litter translocation experiment along a 2800-m elevation gradient in Peruvian tropical forests. The understanding of the environmental factors controlling litter decomposition is important in the description of the carbon and nutrient cycles of tropical ecosystems, and in predicting their response to long-term increases in temperature. • Samples of litter from 15 species were transplanted across all five sites in the study, and decomposition was tracked over 448 d. • Species' type had a large influence on the decomposition rate (k), most probably through its influence on leaf quality and morphology. When samples were pooled across species and elevations, soil temperature explained 95% of the variation in the decomposition rate, but no direct relationship was observed with either soil moisture or rainfall. The sensitivity of the decay rate to temperature (κ(T)) varied seven-fold across species, between 0.024 and 0.169 °C⁻¹, with a mean value of 0.118 ± 0.009 °C⁻¹ (SE). This is equivalent to a temperature sensitivity parameter (Q10) for litter decay of 3.06 ± 0.28, higher than that frequently assumed for heterotrophic processes. • Our results suggest that the warming of approx. 0.9 °C experienced in the region in recent decades may have increased decomposition and nutrient mineralization rates by c. 10%.

Cutoff values of the Inflammatory Bowel Disease Questionnaire to predict a normal health related quality of life.

UNLABELLED: One of the objectives in the treatment of the inflammatory bowel disease (IBD) is improving the patient's quality of life. However, we do not dispose of validated criteria to determine the questionnaire's scoring threshold that has to be reached in order to be able to assert that the patients' quality of life has normalized. OBJECTIVE: To determine the normality punctuation cutoff in the IBD specific quality of life questionnaire IBDQ-36. METHOD: Cross-sectional study in a random sample of IBD patients, who have completed the questionnaires IBDQ-36 and EuroQol-5D. The IBDQ-36 normality was calculated according to its equivalence with the EuroQol-5D tariff ≥ 0.90, which corresponds to the 95% CI of the average obtained in a Spanish general population. RESULTS: 218 patients were included. According to the EuroQol-5D tariff, 70 patients were considered to have a normal quality of life and 148 a quality of life poorer than the general population. The IBDQ-36 scoring was significantly higher in the normal quality of life group (222.9 ± 22.8 vs. 171.4 ± 44.8 in the bad quality of life group, p<0.001). According to the linear regression between IBDQ-36 and EuroQol-5D, the cutoff point is 209, with a sensitivity and specificity to predict normality of 0.74 and 0.71 respectively. CONCLUSIONS: Scores of the IBDQ-36 equal or superior to 209 suggest quality of life comparable to that perceived by the general population. This study allowed to set a threshold of normality in the management of the inflammatory bowel diseases.

The primary tumor is the primary source of metastasis in a human melanoma/SCID model. Implications for the direct autocrine and paracrine epigenetic regulation of the metastasis process.

Although previous autopsy and experimental studies had indicated that metastases can metastasize, the question of whether metastases from metastases increasingly contribute to the overall metastatic burden is crucial to the basic question of whether the metastatic process is more directly regulated by genetic or by epigenetic mechanisms. The highly metastatic human C8161 melanoma was transfected with either pSV2neo or pSV2hygro and clones of neo-C8161 and hyg-C8161 were injected intravenously and subcutaneously in SCID mice. In combination experiments, both the timing and size of inoculum of tumor cells were titrated to ensure that the hematogenously injected cells disseminated almost exclusively to the lungs and that the overall pulmonary burden was equal to the primary tumor. In s.c. injection experiments, no spontaneous metastases ever developed when the primary tumor was extirpated before it had grown to more then 0.5 cm in diameter. When the primary tumor approached 1 cm in diameter, widely-disseminated metastases developed within lungs, liver subcutaneous sites and other internal viscera. In the combination-injection experiments, while large numbers of both hematogenously and spontaneously metastatic clones were recovered from the lungs, a vast excess of only the latter clones was recovered from extrapulmonary sites. Both hematogenously and spontaneously metastatic pulmonary clones recovered showed similar levels of Matrigel invasion and collagenases by substrate gel electrophoresis, but significantly decreased levels when compared to the cell line. Primary tumor clones, in contrast, demonstrated increased invasion and increased collagenases. Our findings argue for the importance of paracrine (orthotopic) and autocrine (size) epigenetic mechanisms in the regulation of metastasis.

A study of the heterogeneity of the mucoepidermoid tumor and the implication for future therapies.

Mucoepidermoid carcinomas are common head and neck neoplasms whose wide distribution includes the major salivary glands, especially parotid, the minor salivary glands within the oropharynx, sites within the larynx, and the submucosal bronchial glands. These tumors are heterogeneous neoplasms composed of intermediate, squamous, and mucous cell subpopulations and have been traditionally classified as low or high grade based on their histological nature and tendency for invasion and metastasis. To gain a better understanding of the heterogeneity of these tumors, we conducted in-depth studies of the different cellular subpopulations obtained from primary human mucoepidermoid carcinomas from various sites, and a derived cell line grown in monolayer culture and as a nude mouse xenograft. Flow cytometric and clonal dilution studies indicate that the intermediate cell behaves as a reserve cell capable of differentiating into either the squamous cell or mucous cell. Immunocytochemical studies of bromodeoxyuridine uptake and Ki-67 antigen expression indicate that whereas the squamous and mucous cells are terminally differentiated and permanently arrested in G0, the intermediate cell actively enters G1 and S. Studies of invasion utilizing a human amnionic membrane indicate that only the intermediate cell is capable of active invasion. Because the mucous and squamous cells are incapable of further division or invasion, therapeutic strategies aimed at differentiating the intermediate cell in vivo into either mucous or squamous directions would serve as useful adjuncts to surgery by reducing the rate of recurrence and the incidence of metastasis.

[Food protection and veterinary public health activities]. / Protección alimentaria y actividades de salud pública veterinaria.

The activities of veterinary public health in protecting food are increasingly numerous and complex, as they aim to prevent food-borne diseases, reduce contamination of foodstuffs, minimise food losses and penalize fraudulent practices. The abrupt changes in social conditions taking place in developing countries, coupled with advances in food technology, have created serious health problems from food-borne diseases and increasing contamination of food which results in massive losses from spoilage. Governments need to implement a wide range of activities, as part of an overall programme, the components of which should be designed to cover closely-related areas; these could be implemented by countries according to their needs and priorities.

[Mucocutaneous leishmaniasis. Histologic classification and anatomoclinical correlations. Apropos of 102 cases]. / Leishmaniose cutanéomuqueuse. Classification histologique et corrélations anatomocliniques. A propos de cent-deux cas.

Two hundred and three skin and mucosal biopsies performed in 162 patients suffering from leishmaniasis, were studied retrospectively. They were classified according to Ridley into 5 histological groups of increasing severity. In cutaneous leishmaniasis, a high proportion of the biopsies belonged to groups III and IV. In mucocutaneous leishmaniasis, the percentage of groups III and VI was lower and group V was present in 20% of cases. In 16 patients, followed by repeated biopsies, we detected some variations of the histological group during the course of the disease. However, there were no positive correlations between clinicopathological features and prognosis.

Effect of bicarbonate and other anions on the oxidized and reduced forms of F1-ATPase.

The effect of activating anions on the hydrolysis of ATP catalyzed by mitochondrial ATPase was higher on the oxidized than on the reduced form of the enzyme. On the contrary the effect of inhibitory anions on this reaction was more manifest on the reduced form of the enzyme. Kinetic data show that both activating and inhibitory anions compete for the same sites of the ATPase. A unifying mechanism of action is suggested according to which the anions could establish coordination bonds with the suggested iron atoms of the catalytic site. The preferential displacement of electrons of such bonds towards the ligand, or towards the metal atom, would lead respectively to an inhibition or to an activation of the enzyme.

Effect of uncouplers and inhibitors of oxidative phosphorylation on the reduced and oxidized forms of mitochondiral ATPase.

A series of uncouplers and inhibitors of oxidative phosphorylation have been studied with regard to their effect on the hydrolytic activity of the reduced and oxidized forms of isolated or membrane-bound mitochondrial ATPase. Uncouplers (2,4-dinitrophenol, dicoumarol), which are also activators of the hydrolytic activity of ATPase, were more potent activators on the oxidized form of the enzyme. Inhibitors of oxidative phosphorylation (oligomycin, azide and amytal) had a more potent inhibitory effect on the hydrolytic activity of ATPase in its reduced form. Purified F1-ATPase, oligomycin insensitive in the oxidized form of the enzyme, became sensitive to oligomycin in the reduced form. An interpretation of the results suggests the presence of a mechanism that unifies the action of these different compounds on the synthesis and hydrolysis of ATP catalyzed by mitochondrial ATPase.

Rat liver mitochondrial F1-ATPase, an FAD containing ferroprotein.

F1-ATPase isolated from rat liver mitochondria has been found to contain approximately 1 mole of FAD and 6 g atoms of nonheme iron per mole of enzyme.