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51.
Guilherme Antonio Rago Lobo Paulo Martin Nowak Ana Paula Panigassi Angélia Iara Felipe Lima Luciano Marcondes Machado Nardozza 《The journal of maternal-fetal & neonatal medicine》2019,32(2):286-292
Objective: The objective of this study is to evaluate the predictive performance of the Fetal Medicine Foundation (FMF) algorithm for prediction of preeclampsia (PE) between 11 and 14 weeks of gestation in an unselected Brazilian population.Methods: We conducted a prospective cohort study with 617 singleton pregnancies of unselected risk. Biophysical markers (mean pulsatility index, mean arterial pressure) and biochemical markers (placental growth factor (PLGF) and PAPP-A) were inserted into the FMF software and converted into multiples of the median (MoM). The subjects were divided into five groups: early-onset PE, parturition <34 weeks’ gestation; preterm PE, parturition <37 weeks; PE, parturition at any gestational age; gestational hypertension (GH); and control group. Areas under the receiver operating characteristics curve (AUC) were calculated for the outcomes.Results: Among 617 patients, seven developed early-onset PE, 18 developed preterm PE (seven early PE plus 11 delivered between 34 and 36?+?6 weeks gestation), 34 developed PE (18 preterm PE plus 16 delivered after 37-week gestation), 12 pregnant women developed GH, and 517 women comprised the control group. The best predictive performance using the FMF algorithm occurred in the early-onset PE group, with AUC?=?0.946 (95% CI 0.919–0.973) and the detection rate of 28.6% and 85.7% for 5% and 10% false-positive (FP), respectively.Conclusions: The FMF algorithm to predict PE was effective in a Brazilian population, mainly in the early-onset form of the disease at 10% FP. 相似文献
52.
Hélio Antonio Guimarães Filho Rosiane Mattar Edward Araujo Júnior Lavoisier Linhares Dias da Costa Carlos Fernando de Mello Junior Luciano Marcondes Machado Nardozza Paulo Martin Nowak Antonio Fernandes Moron 《Archives of gynecology and obstetrics》2011,283(2):213-217
Purpose
Assess intra and interobserver reproducibility of three-dimensional power Doppler (3DPD) placental vascular indices in normal pregnancies between 26 and 35 weeks. 相似文献53.
BDSS Budagoda KAS Kodikara WKS Kularatne RM Mudiyanse DH Edussuriya JP Edirisinghe IP Karunaratne KGAD Weerakoon SC Medagedara SAM Kularatne 《Asian Pacific journal of tropical medicine》2010,3(7):586-588
The sting of Giant Asian honeybee (Apis dorsata) or Bambara in Sinhala and Karunge Kulavi in Tamil is a common environmental hazard in Sri Lanka known to cause immediate allergic reactions, which could be fatal in sensitized individuals. We reported myocardial infarction, bowel gangrene and fatal anaphylaxis in a prospectively proven case series and the association of these uncommon complications with delayed removal of stingers from the patients' skin. 相似文献
54.
55.
Immune regulatory mechanisms influence early pathology in spinal cord injury and in spontaneous autoimmune encephalomyelitis 下载免费PDF全文
Marcondes MC Furtado GC Wensky A Curotto de Lafaille MA Fox HS Lafaille JJ 《The American journal of pathology》2005,166(6):1749-1760
Injuries to the central nervous system (CNS) trigger an inflammatory reaction with potentially devastating consequences. In this report we compared the characteristics of the inflammatory response on spinal cord injury (SCI) caused by a stab wound between the T7 and T9 vertebrae and spontaneous experimental autoimmune encephalomyelitis (EAE). SCI and EAE were compared in two types of myelin basic protein Ac1-11-specific T-cell receptor transgenic mice: T/R+ mice harbor regulatory T cells, and T/R- mice lack regulatory T cells. Our results show that 8 days after SCI, T/R- mice developed a strong T-cell infiltrate in the spinal cord, with remarkable down-modulation of CD4 expression that was accompanied by a local increase in Mac-3+ and F4/80+ reactivity and diffuse local and distal astrogliosis. In contrast, T/R+ mice exhibited a modest increase in CD4+ cells localized to the site of injury, without CD4 down-modulation; focal astrogliosis was restricted to the site of the lesion, although Mac-3+ and F4/80+ cells were also present. Similarly to T/R- mice that underwent SCI, T cells displaying down-modulated CD4 expression were found in the CNS of older T/R- mice afflicted by spontaneous EAE. Overall, our results suggest that common mechanisms regulate T-cell accumulation in CNS lesions of different causes, such as mechanic lesion or autoimmune-mediated damage. 相似文献
56.
Donangelo I Marcos HP Araújo PB Marcondes J Filho PN Gadelha M Chimelli L 《Endocrine pathology》2005,16(1):53-62
The retinoblastoma gene (RB1) is a tumor-suppressor gene in chromosomal region 13q14.2. Its role in the pathogenesis of pituitary tumors has not been
fully clarified. Some studies have shown that losses in this chromosomal region are related to aggressive tumor behavior,
although the retinoblastoma protein (pRB) is still expressed. Conversely, lack of expression of pRB was observed in one fourth
of GH-secreting pituitary adenomas (GH-tumors). In order to further study the expression of pRB in GH-tumors, we evaluated
this protein in 49 tumors from patients with acromegaly (20 noninvasive, 25 invasive, and 4 with no information) and 8 normal
pituitaries using immunohistochemistry (IHC). Nuclear staining for pRB ranged from 0 to 90% (median 40%) in the tumors and
from 40 to 80% (median 58%) in normal pituitaries. In 10 tumors (20% of total) the adenomatous cells were negative (5 cases)
or had very low labeling (5 cases) for pRB. Sixty three percent (31/49) of the tumors showed staining in 10–80% of the cells
and in 16% (8/49) of the cases >80% of the adenomatous cells were positive for pRB. The expression of pRB was not different
in invasive and noninvasive tumors. In conclusion, pRB is underexpressed in a subgroup of GH-tumors, and this may represent
an early event in the pathogenesis of this tumor subtype. 相似文献
57.
58.
The GAP-related domain of tuberin, the product of the TSC2 gene, is a target for missense mutations in tuberous sclerosis 总被引:5,自引:0,他引:5
Maheshwar MM; Cheadle JP; Jones AC; Myring J; Fryer AE; Harris PC; Sampson JR 《Human molecular genetics》1997,6(11):1991-1996
Tuberous sclerosis is an autosomal dominant trait in which the
dysregulation of cellular proliferation and differentiation results in the
development of hamartomatous growths in many organs. The TSC2 gene is one
of two genes determining tuberous sclerosis. Inactivating germline
mutations of TSC2 in patients with tuberous sclerosis and somatic loss of
heterozygosity at the TSC2 locus in the associated hamartomas indicate that
TSC2 functions as a tumour suppressor gene and that loss of function is
critical to expression of the tuberous sclerosis phenotype. The TSC2
product, tuberin, has a region of homology with the GTPase activating
protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in
vitro. Here we show that the region of homology between tuberin and human
rap1GAP and the murine GAP mSpa1 is more extensive than previously reported
and spans approximately 160 amino acid residues encoded within exons 34-38
of the TSC2 gene. Single strand conformation polymorphism analysis of these
exons in 173 unrelated patients with tuberous sclerosis and direct
sequencing of variant conformers together with study of additional family
members enabled characterisation of disease associated mutations in 14
cases. Missense mutations, which occurred in exons 36, 37 and 38 were
identified in eight cases, four of whom shared the same recurrent change
P1675L. Each of the five different missense mutations identified was shown
to occur de novo in at least one sporadic case of tuberous sclerosis. The
high proportion of missense mutations detected in the region of the TSC2
gene encoding the GAP-related domain supports its key role in the
regulation of cellular growth.
相似文献
59.
Bals-Pratsch M; De Geyter C; Muller T; Frieling U; Lerchl A; Pirke KM; Hanker JP; Becker-Carus C; Nieschlag E 《Human reproduction (Oxford, England)》1997,12(5):896-904
Preliminary data have suggested that female infertility due to corpus
luteum insufficiency may be caused by subclinical hypothyroidism
[exaggerated thyroid-stimulating hormone (TSH) response to thyrotrophin-
releasing hormone (TRH) stimulation]. L-Thyroxine supplementation has been
recommended to achieve pregnancies in subclinical hypothyroid women. This
controlled study was carried out in order to investigate the biochemical
diagnosis of subclinical hypothyroidism as a possible infertility factor.
Five infertile patients (aged 25-36 years) with subclinical hypothyroidism
(n = 4, stimulated TSH >20 microU/ml) or primary hypothyroidism (n = 1)
and five healthy controls (aged 22-39 years) with normal thyroid function
(stimulated TSH <15 microU/ml), regular cycles and no history of
infertility were studied in the early follicular phase. In the pre-study
evaluation, eight of 23 volunteers (34.8%) had to be excluded because of
subclinical hypothyroidism with stimulated TSH values (TSHs) >15
microU/ml. Cycle function of patients and controls was compared by the
method of LH pulse pattern analysis. Therefore blood samples were drawn
every 10 min during a 24 h period. Sleep was recorded from midnight to 7
a.m. Repetition of the TRH tests at the end of the 24 h blood sampling
period confirmed the difference in stimulated TSH values of the two study
groups. Pulse analysis for luteinizing hormone (LH), TSH and prolactin
showed no differences between patients and controls for pulse frequency,
amplitude, height, length, area under curve (AUC) and the 24 h mean. Even
the hypothyroid patient had a normal LH pulse pattern. Additional
measurement of melatonin in pooled sera every 30 min gave the
well-documented diurnal profiles during day and night for both groups.
Patients had significantly higher melatonin values at seven time points
during the night. Peaks for LH, TSH, prolactin and cortisol were correlated
with the sleep stages wake, rapid eye movement, 1 + 2 and 3 + 4. We
concluded that corpus luteum insufficiency in female infertility cannot be
explained by subclinical hypothyroidism and thus should not be treated with
L-thyroxine for fertility reasons.
相似文献
60.
Assisted reproductive technology and complex chromosomal rearrangements: the limits of ICSI 总被引:4,自引:0,他引:4
Siffroi JP; Benzacken B; Straub B; Le Bourhis C; North MO; Curotti G; Bellec V; Alvarez S; Dadoune JP 《Molecular human reproduction》1997,3(10):847-851
Complex chromosomal rearrangements are very rare events in the human
population. According to our knowledge on the consequences of simple
reciprocal translocations for male fertility, translocations involving
three or more chromosomes are thought to lead to severe reproductive
impairments in terms of meiotic disturbance or chromosomal imbalance of
gametes. We report the case of a 48 year old man whose sperm count revealed
either oligozoospermia (<10(3) spermatozoa/ml) or azoospermia. He was
referred to the laboratory for in-vitro fertilization after
intracytoplasmic sperm injection. Cytogenetic investigations showed a
complex chromosomal rearrangement involving firstly a translocation between
the short arm of chromosome 7 and the long arm of chromosome 13 and
secondly a translocation between the short arm of the same chromosome 13
and the short arm of chromosome 9. Diagnosis was ascertained by
fluorescence in-situ hybridization and staining of the nucleolar organizer
regions. Theoretical study of the translocated chromosomes predicted a
'chain' configuration of the hexavalent at the pachytene stage of meiosis.
In all, 32 modes of segregation were considered and only one resulted
either in a normal or a balanced gamete karyotype. Genetic counselling and
choice of appropriate artificial reproduction technique are discussed.
相似文献