30 research outputs found
Gravidez com implantação na cicatriz de cesariana anterior
Introdução: Gravidez com implantação na cicatriz de cesariana anterior é um tipo de gravidez
ectópica cada vez mais prevalente, devido ao aumento de cesarianas realizadas em todo o
mundo. Tem uma incidência que varia entre 1:1800 a 1:2216 de todas as gravidezes e
corresponde a 6,1% das gravidezes ectópicas em pacientes que realizaram pelo menos uma
cesariana. Caracteriza-se, habitualmente, por uma implantação na cicatriz de cesariana
anterior, devido a defeitos na correta cicatrização da mesma. É diagnosticada através da
presença de antecedentes de cesariana prévia, com base nos níveis de ß-hCG e de acordo com
os achados ecográficos identificados. Está associada a um elevado risco de efeitos adversos
tais como hemorragia severa, rotura uterina e histerectomia.
Objetivos: Esta dissertação tem como intuito abordar os diferentes métodos terapêuticos da
gravidez com implantação na cicatriz de cesariana anterior, dando destaque ao tratamento
expectante, com o objetivo de compreender a possibilidade de gerar um feto viável através
desta gravidez ectópica, mas também perceber como se pode uniformizar as técnicas
terapêuticas entre os diferentes especialistas.
Metodologia: Foi efetuada pesquisa bibliográfica na plataforma PubMed entre setembro de
2021 e março de 2022.
Resultados: Apesar desta condição ser relativamente incomum, existem diversos estudos
sobre as melhores técnicas terapêuticas e abordagens perante os casos de gravidez de cicatriz
de cesariana, distinguindo-se terapêuticas médicas, cirúrgicas e expectantes tanto para
gravidezes evolutivas como para gravidezes não evolutivas. Em grávidas
hemodinamicamente estáveis é aconselhado tratamento médico ou minimamente invasivo e,
caso as gestantes não queiram interromper a gravidez, é tentado o tratamento expectante,
explicando os riscos e efeitos adversos associados à continuação desta gravidez ectópica.
Histerectomia é uma abordagem cirúrgica utilizada geralmente em último caso, em doentes
que se apresentam com instabilidade hemodinâmica.
Conclusão: A gravidez com implantação na cicatriz de cesariana anterior tem cada vez mais
importância para a comunidade médica, tendo aumentado os conhecimentos sobre a sua
patogénese, diagnóstico e tratamento, verificando-se a necessidade de estabelecer critérios
uniformes para o seguimento e tratamento destas gravidezes ectópicas.Introduction: Caesarean scar pregnancy is an increasingly prevalent type of ectopic
pregnancy, consequence of the increase in caesarean sections performed worldwide. It has
an incidence between 1:1800 to 1:2216 of all pregnancies and corresponds to 6.1% of ectopic
pregnancies in patients who underwent at least one caesarean section. It is usually
characterized by implantation in the scar of a previous caesarean section, due to defects in
its correct healing. The diagnostic is made through the presence of a history of previous
caesarean section, based on the levels of ß-hCG and according to the ultrasound findings. It
is associated with a high risk of adverse effects such as severe bleeding, uterine rupture and
hysterectomy.
Objectives: This dissertation aims to approach the different therapeutic methods of
caesarean scar pregnancy emphasizing the expectant treatment, understanding the
possibility of generating a viable fetus through this ectopic pregnancy, and also
understanding how to standardize therapeutic techniques among different specialists.
Methodology: The literature review was based on the PubMed platform between September
2021 and March 2022.
Results: Although this condition is relatively uncommon, there are several studies on the
best therapeutic techniques and approaches in cases of caesarean scar pregnancy,
distinguishing medical, surgical and expectant therapies for both evolving and nonprogressive pregnancies. In hemodynamically stable pregnant women, medical or
minimally invasive treatment is recommended and, if pregnant women do not want to
terminate the pregnancy, expectant treatment should be tried, explaining the risks and
adverse effects associated with the continuation of this ectopic pregnancy. A hysterectomy
is a surgical approach generally used as a last resort, in patients who present with
hemodynamic instability.
Conclusion: Caesarean scar pregnancy is increasingly highlighted by the medical
community, having increased knowledge about its pathogenesis, diagnosis and treatment,
verifying the need to establish uniform criteria for the follow-up and treatment of these
ectopic pregnancies
Gene Sequence and the 1.8 Å Crystal Structure of the Tungsten-Containing Formate Dehydrogenase from Desulfovibrio gigas
AbstractDesulfovibrio gigas formate dehydrogenase is the first representative of a tungsten-containing enzyme from a mesophile that has been structurally characterized. It is a heterodimer of 110 and 24 kDa subunits. The large subunit, homologous to E. coli FDH-H and to D. desulfuricans nitrate reductase, harbors the W site and one [4Fe-4S] center. No small subunit ortholog containing three [4Fe-4S] clusters has been reported. The structural homology with E. coli FDH-H shows that the essential residues (SeCys158, His159, and Arg407) at the active site are conserved. The active site is accessible via a positively charged tunnel, while product release may be facilitated, for H+ by buried waters and protonable amino acids and for CO2 through a hydrophobic channel
Re-evaluation of the spectroscopic data and redox properties
Eur. J. Biochem. 270, 3904–3915 (2003)The cytochrome c nitrite reductase is isolated from the membranes of the sulfate-reducing bacterium Desulfovibrio desulfuricans ATCC 27774 as a heterooligomeric complex composed by two subunits (61 kDa and 19 kDa) containing
c-type hemes, encoded by the genes nrfA and nrfH,respectively. The extracted complex has in average a 2NrfA:1NrfH composition. The separation of ccNiR subunits from one another is accomplished by gel filtration
chromatography in the presence of SDS. The amino-acid sequence and biochemical subunits characterization show that NrfA contains five hemes and NrfH four hemes. These
considerations enabled the revision of a vast amount of existing spectroscopic data on the NrfHA complex that was not originally well interpreted due to the lackof knowledge
on the heme content and the oligomeric enzyme status.
Based on EPRandMo¨ ssbauer parameters and their correlation to structural information recently obtained from X-ray crystallography on the NrfA structure [Cunha, C.A., Macieira, S., Dias, J.M., Almeida, M.G., Gonçalves, L.M.L., Costa, C., Lampreia, J.,Huber,R., Moura, J.J.G., Moura, I. & Romão, M. (2003) J. Biol. Chem. 278, 17455–
17465], we propose the full assignment of midpoint reduction potentials values to the individual hemes.NrfAcontains the high-spin catalytic site ()80mV) as well as a quite
unusual high reduction potential (+150 mV)/low-spin bis-His coordinated heme, considered to be the site where
electrons enter. In addition, the reassessment of the spectroscopic
data allowed the first partial spectroscopic characterization of theNrfH subunit. The four NrfH hemes are all in a low-spin state (S ¼ 1/2).One of them has a gmax at 3.55, characteristic of bis-histidinyl iron ligands in a noncoplanar arrangement, and has a positive reduction potential
The relevance of the two calcium sites inthe structure of the catalytic subunit (NrfA)
The Journal of Biological Chemistry Vol. 278, No. 19, Issue of May 9, pp. 17455–17465, 2003The gene encoding cytochrome c nitrite reductase(NrfA) from Desulfovibrio desulfuricans ATCC 27774 was sequenced and the crystal structure of the enzyme
was determined to 2.3-Å resolution. In comparison with homologous structures, it presents structural differences mainly located at the regions surrounding the
putative substrate inlet and product outlet, and includes a well defined second calcium site with octahedral geometry, coordinated to propionates of hemes 3 and 4, and caged by a loop non-existent in the previous
structures. The highly negative electrostatic potential in the environment around hemes 3 and 4 suggests that
the main role of this calcium ion may not be electrostatic but structural, namely in the stabilization of the conformation of the additional loop that cages it and influences
the solvent accessibility of heme 4. The NrfA active site is similar to that of peroxidases with a nearby calcium site at the heme distal side nearly in the same
location as occurs in the class II and class III peroxidases.
This fact suggests that the calcium ion at the distal side of the active site in the NrfA enzymes may have a similar physiological role to that reported for
the peroxidases
Reuma.pt/vasculitis - the Portuguese vasculitis registry
BACKGROUND: The vasculitides are a group of rare diseases with different manifestations and outcomes. New therapeutic options have led to the need for long-term registries. The Rheumatic Diseases Portuguese Register, Reuma.pt, is a web-based electronic clinical record, created in 2008, which currently includes specific modules for 12 diseases and > 20,000 patients registered from 79 rheumatology centres. On October 2014, a dedicated module for vasculitis was created as part of the European Vasculitis Society collaborative network, enabling prospective collection and central storage of encrypted data from patients with this condition. All Portuguese rheumatology centres were invited to participate. Data regarding demographics, diagnosis, classification criteria, assessment tools, and treatment were collected. We aim to describe the structure of Reuma.pt/vasculitis and characterize the patients registered since its development. RESULTS: A total of 687 patients, with 1945 visits, from 13 centres were registered; mean age was 53.4 ± 19.3 years at last visit and 68.7% were females. The most common diagnoses were Behçet's disease (BD) (42.5%) and giant cell arteritis (GCA) (17.8%). Patients with BD met the International Study Group criteria and the International Criteria for BD in 85.3 and 97.2% of cases, respectively. Within the most common small- and medium-vessel vasculitides registered, median [interquartile range] Birmingham Vasculitis Activity Score (BVAS) at first visit was highest in patients with ANCA-associated vasculitis (AAV) (17.0 [12.0]); there were no differences in the proportion of patients with AAV or polyarteritis nodosa who relapsed (BVAS≥1) or had a major relapse (≥1 major BVAS item) during prospective assessment (p = 1.00, p = 0.479). Biologic treatment was prescribed in 0.8% of patients with GCA, 26.7% of patients with AAV, and 7.6% of patients with BD. There were 34 (4.9%) deaths reported. CONCLUSIONS: Reuma.pt/vasculitis is a bespoke web-based registry adapted for routine care of patients with this form of rare and complex diseases, allowing an efficient data-repository at a national level with the potential to link with other international databases. It facilitates research, trials recruitment, service planning and benchmarking.publishersversionpublishe
Global variation in diabetes diagnosis and prevalence based on fasting glucose and hemoglobin A1c
Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) are both used to diagnose diabetes, but these measurements can identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening, had elevated FPG, HbA1c or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardized proportion of diabetes that was previously undiagnosed and detected in survey screening ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the age-standardized proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c was more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global shortfall in diabetes diagnosis and surveillance
Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants
Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks
Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults
Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We
estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from
1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories.
Methods We used data from 3663 population-based studies with 222 million participants that measured height and
weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate
trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children
and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the
individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference)
and obesity (BMI >2 SD above the median).
Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in
11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed
changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and
140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of
underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and
countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior
probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse
was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of
thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a
posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%)
with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and
obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for
both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such
as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged
children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls
in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and
42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents,
the increases in double burden were driven by increases in obesity, and decreases in double burden by declining
underweight or thinness.
Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an
increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy
nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of
underweight while curbing and reversing the increase in obesit
Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c
Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose
diabetes, but may identify different people as having diabetes. We used data from 117
population-based studies and quantified, in different world regions, the prevalence of
diagnosed diabetes, and whether those who were previously undiagnosed and detected
as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed
prediction equations for estimating the probability that a person without previously
diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa.
The age-standardised proportion of diabetes that was previously undiagnosed, and
detected in survey screening, ranged from 30% in the high-income western region to 66%
in south Asia. Among those with screen-detected diabetes with either test, the agestandardised
proportion who had elevated levels of both FPG and HbA1c was 29-39%
across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and
middle-income regions, isolated elevated HbA1c more common than isolated elevated
FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and
underestimate diabetes prevalence. Our prediction equations help allocate finite
resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and
surveillance.peer-reviewe