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The single-station microtremor horizontal-to-vertical spectral ratio (MHVSR) method was initially proposed to retrieve the site amplification function and its resonance frequencies produced by unconsolidated sediments overlying high-velocity bedrock. Presently, MHVSR measurements are predominantly conducted to obtain an estimate of the fundamental site frequency at sites where a strong subsurface impedance contrast exists. Of the earthquake site characterization methods presented in this special issue, the MHVSR method is the furthest behind in terms of consensus towards standardized guidelines and commercial use. The greatest challenges to an international standardization of MHVSR acquisition and analysis are (1) the what - the underlying composition of the microtremor wavefield is site-dependent, and thus, the appropriate theoretical (forward) model for inversion is still debated; and (2) the how - many factors and options are involved in the data acquisition, processing, and interpretation stages. This paper reviews briefly a historical development of the MHVSR technique and the physical basis of an MHVSR (the what). We then summarize recommendations for MHVSR acquisition and analysis (the how). Specific sections address MHVSR interpretation and uncertainty assessment.
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Vesicovaginal fistula (VVF) is the most common genitourinary fistula associated with significant, detrimental impact on the quality of life. Surgical repair of VVF may be complex requiring tissue interposition techniques to bring fresh blood supply, minimize recurrence, and improve functional outcomes. The international literature is scarce regarding complications related to interposition tissue. However, caution is particularly recommended in selecting the tissue interposition technique to avoid unexpected and frustrating problems. We present a 57-year-old woman following multiple failed transvaginal and transabdominal VVF repairs involving a labium majus skin island flap (Lehoczky flap) after radical hysterectomy for cervical cancer.
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Endometrial cancer is the most common gynecological malignancy with a relatively good overall prognosis. It traditionally has two subtypes: type 1 (endometrioid carcinoma) and type 2 (non-endometrioid carcinoma). The prognosis is excellent for stage I endometrioid cancer, with a 5-year survival rate of 96%. However, the prognosis is much worse for women with high-risk endometrial cancer. Effective preoperative staging is important in order to tailor treatment and achieve optimal long-term survival. The majority of asymptomatic polyps detected by ultrasound are treated surgically. Conventionally, dilatation and curettage was performed to obtain a histological diagnosis, but nowadays hysteroscopy with biopsy is starting to be considered as the gold standard. Hysteroscopic resection seems to reduce the risk of underdiagnosed (atypical endometrial hyperplasia) endometrial cancer. To avoid the spread of malignant cells, hysteroscopy should be performed with concern to keep intrauterine pressure low. In comparison with cervical injection, the hysteroscopic method has a better detection rate in the para-aortic area during sentinel lymph node mapping. In the assessment of cervical involvement, the accuracy of magnetic resonance imaging is significantly higher than the accuracy of hysteroscopy. In fertility-sparing cases, hysteroscopic endometrium resection with progesterone therapy is an acceptable option.
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Neoplasias do Endométrio/cirurgia , Endométrio/cirurgia , Histeroscopia/métodos , Colo do Útero/cirurgia , Feminino , HumanosRESUMO
Introduction: Most endometrial polyps represent focal hyperplasia of the endometrium. Endometrial polyps can be diagnosed by ultrasound, hysterocontrast sonography, hysterosalpingography, endometrial biopsy, and uterine curettage, but diagnostic hysteroscopy is considered the gold-standard method, with the greatest sensitivity and specificity and also with the opportunity for treatment at the same time.Study design: A retrospective study was conducted on 424 patients between 2006 and 2018. The polyps were verified during diagnostic hysteroscopy and were removed by resectoscopy or curettage. All samples underwent histological examination. The effectivity of the type of resection and the recurrence rate were evaluated.Results: The average age of the patients was 60.2 ± 9.3 years. Polyps were excised in 62.97% by resectoscopic polypectomy and in 37.03% by curettage. Malignancy was confirmed in 4.24% of cases. Histological verification of polyps was 79.4% in the resectoscopy group and 69.04% in the curettage group; the difference was significant (p < 0.01). The recurrence rate was 20.47% after resectoscopy and 27.12% following curettage.Conclusion: Hysteroscopy remains the best option and the gold-standard method among diagnostic procedures of endometrial pathology. In this study, there was a significant difference in matching hysteroscopic and histological findings in the two methods of polypectomy. The recurrence rate is also lower following resectoscopy.
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Curetagem/métodos , Neoplasias do Endométrio/cirurgia , Histeroscopia/métodos , Recidiva Local de Neoplasia/epidemiologia , Pólipos/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Endométrio/patologia , Endométrio/patologia , Endométrio/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Pólipos/patologia , Pós-Menopausa , Período Pós-Operatório , Estudos Retrospectivos , Estatísticas não Paramétricas , Resultado do TratamentoRESUMO
Several Romanian hospitals have noted increasing isolation of Providencia stuartii strains in recent years, with an alarming rate of carbapenem resistance. In order to provide molecular epidemiological data regarding their dissemination, 77 P. stuartii strains collected from five hospitals located in different regions of Romania were analysed. All strains harboured IncA/C plasmid, and 67 carried the blaNDM-1 gene. Six clonal clusters were differentiated by pulsed-field gel electrophoresis. The predominant subtype was found in all five hospitals. Our study highlights the need for efficient infection-control measures, the optimization of antibiotic use and the targeted surveillance for carbapenemase-producing P. stuartii.
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Infecção Hospitalar/epidemiologia , Infecções por Enterobacteriaceae/epidemiologia , Providencia/enzimologia , Providencia/isolamento & purificação , beta-Lactamases/genética , Infecção Hospitalar/transmissão , Infecções por Enterobacteriaceae/transmissão , Genótipo , Hospitais , Humanos , Epidemiologia Molecular , Tipagem Molecular , Plasmídeos/análise , Providencia/classificação , Providencia/genética , Romênia/epidemiologiaRESUMO
BACKGROUND: Recommendations for management of cancer-related venous thromboembolism (VTE) in patients already receiving anticoagulant therapy are based on low-quality evidence. This international registry sought to provide more information on outcomes after a breakthrough VTE in relation to anticoagulation strategies. METHODS: Patients with cancer and VTE despite anticoagulant therapy were reported to the registry. Data on treatments, VTE events, major bleeding, residual thrombosis symptoms and death were collected for the following 3 months. Breakthrough VTE and subsequent recurrences were objectively verified. Outcomes with different treatment strategies were compared with Cox proportional hazards regression. RESULTS: We registered 212 patients with breakthrough VTE. Of those, 59% had adenocarcinoma and 73% had known metastases. At the time of the breakthrough event, 70% were on low-molecular-weight heparin (LMWH) and 27% on a vitamin K antagonist (VKA); 70% had a therapeutic or supratherapeutic dose. After breakthrough the regimen was: unchanged therapeutic dose in 33%, dose increased in 31%, switched to another drug in 24%; and other management in 11%. During the following 3 months 11% had another VTE, 8% had major bleeding and 27% died. Of the survivors, 74% had residual thrombosis symptoms. Additional VTE recurrence was less common with LMWH than with a VKA (hazard ratio [HR], 0.28; 95% confidence interval [CI], 0.11-0.70) but similar with unchanged or increased anticoagulant intensity (HR, 1.09; 95% CI, 0.45-2.63). The bleeding rate did not increase significantly with dose escalation. CONCLUSION: Morbidity and mortality are high after recurrence of cancer-related VTE despite anticoagulation. Further treatment appears to be more effective with LMWH than with a VKA.
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Anticoagulantes/administração & dosagem , Heparina de Baixo Peso Molecular/administração & dosagem , Neoplasias/complicações , Tromboembolia Venosa/tratamento farmacológico , Varfarina/administração & dosagem , Idoso , Anticoagulantes/efeitos adversos , Distribuição de Qui-Quadrado , Substituição de Medicamentos , Feminino , Hemorragia/induzido quimicamente , Heparina de Baixo Peso Molecular/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/mortalidade , Neoplasias/patologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Recidiva , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Tromboembolia Venosa/sangue , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/mortalidade , Vitamina K/antagonistas & inibidores , Varfarina/efeitos adversosRESUMO
Linear verticum-type control and observation systems have been introduced for modelling certain industrial systems, consisting of subsystems, vertically connected by certain state variables. Recently the concept of verticum-type observation systems and the corresponding observability condition have been extended by the authors to the nonlinear case. In the present paper the general concept of a nonlinear verticum-type control system is introduced, and a sufficient condition for local controllability to equilibrium is obtained. In addition to a usual linearization, the basic idea is a decomposition of the control of the whole system into the control of the subsystems. Starting from the integrated pest control model of Rafikov and Limeira (2012) and Rafikov et al. (2012), a nonlinear verticum-type model has been set up an equilibrium control is obtained. Furthermore, a corresponding bioeconomical problem is solved minimizing the total cost of integrated pest control (combining chemical control with a biological one).
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Modelos Teóricos , Controle Biológico de Vetores/métodos , Biologia de Sistemas/métodosRESUMO
We report integration of an InAs quantum well micro-Hall magnetic sensor with microfluidics and real-time detection of moving superparamagnetic beads. Beads moving within and around the Hall cross area result in positive and negative Hall voltage signals respectively. Relative magnitudes and polarities of the signals measured for a random distribution of immobilized beads over the sensor are in good agreement with calculated values and explain consistently the shape of the dynamic signal.
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The monitoring and analysis of the processes taking place in an ecosystem is a key issue for a sustainable human activity. A system of populations, as the biotic component of a complex ecosystem is usually affected by the variation of its abiotic environment. Even in nearly natural ecosystems an abiotic effect like climatic implications of global warming may cause important changes in the dynamics of the population system. In ecosystems involving field cultivation or any industrial activity; the abiotic parameter in question may be the concentration of a substance, changing, e.g. as a result of pollution, application of a pesticide, or a fertilizer, etc. In many cases the observation of the densities of each population may be technically complicated or expensive, therefore the question arises whether from the observation of the densities of certain (indicator) populations, the whole state process of the population system can be uniquely recovered. The paper is aimed at a methodological development of the state monitoring, under the conditions of a changing environment. It is shown, how the technique of mathematical systems theory can be applied not only for the approximate calculation of the state process on the basis of the observed data, even under the effect of an exogene abiotic change with known dynamics; but in certain cases, also for the estimation of the unknown biological effect of the change of an abiotic parameter. The proposed methodology is applied to simple illustrative examples concerning a three-species predator-prey system.
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Ecossistema , Monitoramento Ambiental , AnimaisRESUMO
The degree of aluminium tolerance varies widely across cereal species, with oats (Avena spp.) being among the most tolerant. The objective of this study was to identify molecular markers linked to aluminium tolerance in the diploid oat A. strigosa. Restriction fragment length polymorphism markers were tested in regions where comparative mapping indicated the potential for orthologous quantitative trait loci (QTL) for aluminium tolerance in other grass species. Amplified fragment length polymorphism (AFLP) and sequence-characterized amplified region (SCAR) markers were used to provide additional coverage of the genome. Four QTL were identified. The largest QTL explained 39% of the variation and is possibly orthologous to the major gene found in the Triticeae as well as Alm1 in maize and a minor gene in rice. A second QTL may be orthologous to the Alm2 gene in maize. Two other QTL were associated with anonymous markers. Together, these QTL accounted for 55% of the variation. A SCAR marker linked to the major QTL identified in this study could be used to introgress the aluminium tolerance trait from A. strigosa into cultivated oat germplasm.
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Alumínio/farmacologia , Avena/efeitos dos fármacos , Avena/genética , Cromossomos de Plantas/genética , Diploide , Locos de Características Quantitativas/genética , Alumínio/metabolismo , Avena/metabolismo , Tolerância a Medicamentos/genética , Genes de Plantas , Marcadores Genéticos/genética , Fenótipo , Mapeamento Físico do Cromossomo , Raízes de PlantasRESUMO
Evaluamos pacientes para identifica factores determinantes de estadía hospitalaria prolongada y complicaciones de la misma. MATERIAL Y MÉTODO: estudio retrospectivo descriptivo. Los datos se procesaron utilizando Chi' , Test de Fisher y Test T según variables. Definimos internación prolongada (IP) estadía hospitalaria igual o mayor a 10 días. RESULTADOS: se analizaron 322 pacientes. Cincuenta (15.5%) presentaron IP y 272 (84.5%) estadía < 10 días. El promedio de edad fue 63.8 para < 10 días y 66 para IP . Presentaron comorbilidades 87% en <10 días y 86% IP. Los diagnósticos de ingreso más frecuentes en < 10 días fueron patología respiratoria (25%). incluyendo neumonía (10%), infección urinaria e insuficiencia cardiaca; y en IP neumonía (20%) y patología neurológica aguda (18%) . El 46% de IP requirió cirugía vs 20.6% (p
In order to identify determining factors and complications in illness, we evaluated patients under long period hospitalization, in a Clinical Service. METHODS: retrospective and descriptive studies. Figures were evaluated by Chi-, Fisher T and Test T, thrue variables. We call long period hospitalization to a staying of 10 days or longer. RESULTS: 322 patients were evaluated. 50 (15,5%) presented (LS) and 272 < 10 days staying. Age average was 63,8 for < 10 days and 66 for (LS). Mostly of diagnosis at admission for < 10 days were respiratory dysfunction (25%) including pneumonia (10%), urinary infection and heart failure, and for LS pneumonia 20%, acute neurological disease 18 %. The 46 % of LS required surgery vs. 20,6% (p < 1,01). The LS needed parenteral nutrition 26 % vs. 12,5% (p < 0,02). The average of maximum amount of drugs/day in staying was: 5,8 for < 10 days and 8,76 for LS (p < 0,01). Hospital complications in LS were 28 % vs. 11% (p < 0,01), mainly nosocomial pneumonia (p < 0,01) and endovascular infections (p < 0,01). Staying in ICU was 54% for LS vs. 19% (p < 0,01), and average of days in intensive care unit (ICU) was 8 in LS vs. 3 (p < 0,01). There wasn't any difference in mortality. CONCLUSION: the admission's diagnosis and the ICU's staying were the main causes of LS, but not so age and co-morbilities studied. The LS patients require more complex and expensive staying. They present more hospital complications.
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Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Tempo de Internação , Argentina/epidemiologia , Custos e Análise de Custo , Estudos Epidemiológicos , Unidades de Terapia Intensiva , Infecção Hospitalar/epidemiologia , Estudos Retrospectivos , Tempo de Internação/economiaRESUMO
In spring-type oat ( Avena sativa L.), quantitative trait loci (QTLs) detected in adapted populations may have the greatest potential for improving germplasm via marker-assisted selection. An F(6) recombinant inbred (RI) population was developed from a cross between two Canadian spring oat varieties: 'Terra', a hulless line, and 'Marion', an elite covered-seeded line. A molecular linkage map was generated using 430 AFLP, RFLP, RAPD, SCAR, and phenotypic markers scored on 101 RI lines. This map was refined by selecting a robust set of 124 framework markers that mapped to 35 linkage groups and contained 35 unlinked loci. One hundred one lines grown in up to 13 field environments in Canada and the United States between 1992 and 1997 were evaluated for 16 agronomic, kernel, and chemical composition traits. QTLs were localized using three detection methods with an experiment-wide error rate of approximately 0.05 for each trait. In total, 34 main-effect QTLs affecting the following traits were identified: heading date, plant height, lodging, visual score, grain yield, kernel weight, milling yield, test weight, thin and plump kernels, groat beta-glucan concentration, oil concentration, and protein. Several of these correspond to QTLs in homologous or homoeologous regions reported in other oat QTL studies. Twenty-four QTL-by-environment interactions and three epistatic interactions were also detected. The locus controlling the covered/hulless character ( N1) affected most of the traits measured in this study. Additive QTL models with N1 as a covariate were superior to models based on separate covered and hulless sub-populations. This approach is recommended for other populations segregating for major genes. Marker-trait associations identified in this study have considerable potential for use in marker-assisted selection strategies to improve traits within spring oat breeding programs.
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Avena/genética , Mapeamento Cromossômico , Meio Ambiente , Fenótipo , Locos de Características Quantitativas/genética , Agricultura/métodos , Canadá , Cruzamentos Genéticos , Modelos Lineares , Polimorfismo de Fragmento de Restrição , Técnica de Amplificação ao Acaso de DNA Polimórfico , Estados UnidosRESUMO
The DNA sequence of an extracellular (EXC) domain of an oat (Avena sativa L.) receptor-like kinase (ALrk10) gene was amplified from 23 accessions of 15 Avena species (6 diploid, 6 tetraploid, and 3 hexaploid). Primers were designed from one partial oat ALrk10 clone that had been used to map the gene in hexaploid oat to linkage groups syntenic to Triticeae chromosome 1 and 3. Cluster (phylogenetic) analyses showed that all of the oat DNA sequences amplified with these primers are orthologous to the wheat and barley sequences that are located on chromosome 1 of the Triticeae species. Triticeae chromosome 3 Lrk10 sequences were not amplified using these primers. Cluster analyses provided evidence for multiple copies at a locus. The analysis divided the ALrk EXC sequences into two groups, one of which included AA and AABB genome species and the other CC, AACC, and CCCC genome species. Both groups of sequences were found in hexaploid AACCDD genome species, but not in all accessions. The C genome group was divided into 3 subgroups: (i) the CC diploids and the perennial autotetraploid, Avena macrostachya (this supports other evidence for the presence of the C in this autotetraploid species); (ii) a sequence from Avena maroccana and Avena murphyi and several sequences from different accessions of A. sativa; and (iii) A. murphyi and sequences from A. sativa and Avena sterilis. This suggests a possible polyphyletic origin for A. sativa from the AACC progenitor tetraploids or an origin from a progenitor of the AACC tetraploids. The sequences of the A genome group were not as clearly divided into subgroups. Although a group of sequences from the accession 'SunII' and a sequence from line Pg3, are clearly different from the others, the A genome diploid sequences were interspersed with tetraploid and hexaploid sequences.
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Avena/genética , Diploide , Proteínas de Plantas , Poliploidia , Proteínas Serina-Treonina Quinases/genética , Avena/enzimologia , Primers do DNA , Hordeum/genética , Oryza/genética , Filogenia , Estrutura Terciária de Proteína , Análise de Sequência de DNA , Triticum/genéticaRESUMO
UNLABELLED: Significantly higher levels of arachidonic acid (AA) and docosahexaenoic acid (DHA) in plasma lipids have previously been reported in 2 to 8-wk-old as well as in 6 to 12-mo-old full-term infants fed exclusively human milk than in infants exclusively receiving formula without AA and DHA. However, in real life many infants receive both human milk and breast milk substitute formula. Healthy, full-term infants aged 2 to 12 mo and fed exclusively human milk (n = 29, age: 29.2 [14.6] wk, mean [SD], no human milk substitute formula), exclusively formula without AA and DHA (n = 30, age: 26.6 [15.2] wk, no human milk after the age of 1 mo) or combined diet (n = 38, age: 30.3 [12.8] wk, human milk for > 1 mo and breast milk substitute formula) were investigated in this cross-sectional study. Fatty acid composition of erythrocyte membrane phosphatidylethanolamine (PE), phosphatidylcholine and sphingomyeline lipids was determined by high-resolution capillary gas-liquid chromatography. The most pronounced diet-related differences were seen in PE lipids. Values of PE alpha-linolenic acid (0.07 [0.05] vs 0.26 [0.18] vs 0.19 [0.19], median [range from the 1st to the 3rd quartile], exclusively breastfed vs. exclusively formula fed vs combined diet), eicosapentaenoic acid (0.19 [0.13] vs 0.35 [0.23] vs 0.27 [0.31]) and dihomo-gamma-linolenic acid (1.34 [0.42] vs 1.86 [0.62] vs 1.58 [0.73]) were significantly lower in exclusively breastfed infants than in those fed formula, exclusively or partially. In contrast, PE AA (26.48 [2.50] vs 24.34 [4.74] vs 24.94 [3.64]) and DHA (4.93 [2.91] vs 3.51 [2.14] vs 3.58 [2.27]) values were significantly higher in exclusively breastfed infants than in the other two groups. CONCLUSION: In full-term infants aged 2 to 12 mo, erythrocyte membrane AA and DHA values are significantly higher with exclusive breastfeeding than with partial breastfeeding or exclusive feeding of formula without AA and DHA.
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Alimentação com Mamadeira , Aleitamento Materno , Membrana Eritrocítica/química , Ácidos Graxos/sangue , Alimentos Infantis , Lipídeos de Membrana/sangue , Leite Humano , Ácido Araquidônico/sangue , Estudos Transversais , Ácidos Docosa-Hexaenoicos/sangue , Feminino , Humanos , Lactente , MasculinoRESUMO
In our country, the hydrostatic reduction is performed in three different ways. 1. A method with negative contrast material (gas enema) and fluoroscopy is performed only in one hospital. 2. A second method is performed with the use of Gastrographin and guided with ultrasound examination, and finally controlled with x-ray, this method is used in the most places. 3. Sonographically guided enema using physiological saline solution which has been performed by the authors for five years is only used in the Transdanubian region and is getting more and more popular in the resent years. The case history of 34 patients with intussusception was analysed retrospectively and the results of hydrostatic reduction with ultrasound guidance were reviewed. In 22 of 34 patients vomiting was noticed, blood in the stool was found in approximately one-third of all cases, the abdominal pain as the most important sign was presented by all patients. In 24 of 34 patients with intussusception, a single hydrostatic reduction was completely successful, but 10 patients were operated on. With the use of author's method, the following advantages were noticed: control X-ray examination was not needed, and in cases of multiple intussusception of the small intestines all of the lesions were detected.
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Pressão Hidrostática , Intestino Delgado/diagnóstico por imagem , Intussuscepção/diagnóstico por imagem , Intussuscepção/terapia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Recidiva , Estudos Retrospectivos , Cloreto de Sódio , Falha de Tratamento , Resultado do Tratamento , UltrassonografiaRESUMO
This review describes a new paradigm of electronics based on the spin degree of freedom of the electron. Either adding the spin degree of freedom to conventional charge-based electronic devices or using the spin alone has the potential advantages of nonvolatility, increased data processing speed, decreased electric power consumption, and increased integration densities compared with conventional semiconductor devices. To successfully incorporate spins into existing semiconductor technology, one has to resolve technical issues such as efficient injection, transport, control and manipulation, and detection of spin polarization as well as spin-polarized currents. Recent advances in new materials engineering hold the promise of realizing spintronic devices in the near future. We review the current state of the spin-based devices, efforts in new materials fabrication, issues in spin transport, and optical spin manipulation.
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BACKGROUND: Previous studies showed significant inverse correlations between values of trans isomeric and long-chain polyunsaturated fatty acids in plasma lipids of preterm infants and healthy children aged 1-15 y. OBJECTIVE: We sought to evaluate the same correlations in full-term infants at birth. DESIGN: We studied healthy full-term infants (n = 42) born after normal pregnancies and deliveries. All infants had a family history of atopy (both parents or one of the parents and a sibling had atopic symptoms). The fatty acid composition of venous cord blood lipids was determined by high-resolution capillary gas-liquid chromatography. RESULTS: The mean (+/-SEM) sum of trans fatty acids was 0.49 +/- 0.02% by wt in phospholipids, 2.47 +/- 0.20% by wt in cholesterol esters, 1.73 +/- 0.09% by wt in triacylglycerols, and 1.59 +/- 0.07% by wt in nonesterified fatty acids. Linear correlation analysis showed significant inverse correlations between the sum of trans fatty acids and both arachidonic acid and docosahexaenoic acid in phospholipids (r = -0.56, P < 0.001, and r = -0.48, P = 0.01, respectively), cholesterol esters (r = -0.52, P < 0.001, and r = -0.39, P = 0.018, respectively), and nonesterified fatty acids (r = -0.41, P = 0.007, and r = -0.41, P = 0.006, respectively). CONCLUSION: Because trans fatty acids in the fetal circulation must originate from the maternal diet, our results indicate that maternal exposure to trans fatty acids may represent a previously neglected variable that inversely influences long-chain polyunsaturated fatty acid status in full-term infants at birth.
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Ácidos Graxos Insaturados/sangue , Sangue Fetal/química , Feto/metabolismo , Ésteres do Colesterol/sangue , Ésteres do Colesterol/química , Cromatografia Gasosa , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6 , Ácidos Graxos Insaturados/metabolismo , Feminino , Humanos , Recém-Nascido , Isomerismo , Masculino , Troca Materno-Fetal , Fenômenos Fisiológicos da Nutrição , Fosfolipídeos/sangue , Fosfolipídeos/química , Gravidez , Triglicerídeos/sangue , Triglicerídeos/químicaRESUMO
Previously we reported significantly higher values of gamma-linolenic acid (GLA, 18:3n-6), dihomo-gamma-linolenic acid (DHGLA, 20:3n-6), and arachidonic acid (20:4n-6) in plasma lipid classes in obese children than in nonobese controls. In the present study, fatty acid composition of plasma phospholipids (PL) and sterol esters (STE) was determined by high-resolution capillary gas-liquid chromatography in obese children with and without metabolic cardiovascular syndrome [MCS: defined as simultaneous presence of (i) dyslipidemia, (ii) hyperinsulinemia, (iii) hypertension, and.(iv) impaired glucose tolerance] and in nonobese controls. Fatty acid composition of PL and STE lipids did not differ between obese children without MCS and controls. Obese children with MCS exhibited significantly lower linoleic acid (LA, 18:2n-6) values in PL (17.43 [2.36], % wt/wt, median [range from the first to the third quartile]) than obese children without MCS (19.14 [3.49]) and controls (20.28 13.80]). In contrast, PL GLA values were significantly higher in obese children with (0.13 [0.08]) than in those without MCS (0.08 [0.04]), whereas STE GLA values were higher in obese children with MCS (1.04 [0.72]) than in controls (0.62 [0.48]). DHGLA values in PL were significantly higher in obese children with MCS (4.06 [0.74]) than in controls (2.69 [1.60]). The GLA/LA ratio was significantly higher, whereas the AA/DHGLA ratio was significantly lower in obese children with MCS than in obese children without MCS and in controls. In this study, LA metabolism was affected only in obese children with but not in those without MCS. In obese children with MCS, delta6-desaturase activity appeared to be stimulated, whereas delta5-desaturase activity appeared to be inhibited. Disturbances in LA metabolism may represent an additional health hazard within the multifaceted clinical picture of MCS.