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1.
Proc Natl Acad Sci U S A ; 120(26): e2303292120, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37339194

RESUMO

The ongoing COVID-19 pandemic has had great societal and health consequences. Despite the availability of vaccines, infection rates remain high due to immune evasive Omicron sublineages. Broad-spectrum antivirals are needed to safeguard against emerging variants and future pandemics. We used messenger RNA (mRNA) display under a reprogrammed genetic code to find a spike-targeting macrocyclic peptide that inhibits SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) Wuhan strain infection and pseudoviruses containing spike proteins of SARS-CoV-2 variants or related sarbecoviruses. Structural and bioinformatic analyses reveal a conserved binding pocket between the receptor-binding domain, N-terminal domain, and S2 region, distal to the angiotensin-converting enzyme 2 receptor-interaction site. Our data reveal a hitherto unexplored site of vulnerability in sarbecoviruses that peptides and potentially other drug-like molecules can target.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Pandemias/prevenção & controle , Peptídeos/farmacologia
2.
ESMO Open ; 8(2): 101201, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36965262

RESUMO

INTRODUCTION: Body surface area (BSA)-based dosing of 5-fluorouracil (5-FU) results in marked inter-individual variability in drug levels, whereas determination of plasma 5-FU concentration and area under the curve (AUC) is a more precise dosing method but has not been integrated into clinical routine. We conducted a multicenter, prospective study to study 5-FU AUC distributions and assess clinical factors predicting therapeutic dosing in patients receiving BSA-dosed 5-FU. METHODS: Between June 2017 and January 2018, a total of 434 patients receiving continuous, infusional BSA-dosed 5-FU from 37 sites in Germany were included. Plasma 5-FU concentration and AUC were measured in venous blood samples at steady state. The primary objective was to determine 5-FU AUC distributions in relation to the target range, which is defined as 20-30 mg × h/l. The second objective was to explore clinical parameters that correlate with achievement of 5-FU AUC target range. RESULTS: The primary tumor was mainly located in the gastrointestinal tract (96.3%), with colorectal cancer being the most common (71.2%) tumor entity. 5-FU was administered as monotherapy (8.1%) or as part of FOLFOX (33.2%), FOLFIRI (26.3%), or other regimens (12.4%). Treatment setting was adjuvant (31.3%) or metastatic (64.5%). The median AUC was 16 mg × h/l. Only 20.3% of patients received 5-FU treatment within the target range, whereas the majority of patients (60.6%) were underdosed and 19.1% of patients were overdosed. In the univariate logistic regression, treatment setting was the only clinical parameter that significantly correlated with achievement of the target range. Patients treated in the metastatic setting had a 2.1 (95% confidence interval 1.186-3.776, P = 0.011) higher odds to reach the target range compared with patients treated in the adjuvant setting. CONCLUSIONS: The majority of patients received suboptimal doses of 5-FU using BSA dosing. Therapeutic drug monitoring of 5-FU is an option for optimized individualized cancer therapy and should be integrated into the clinical practice.


Assuntos
Neoplasias Colorretais , Fluoruracila , Humanos , Fluoruracila/uso terapêutico , Fluoruracila/efeitos adversos , Estudos Prospectivos , Monitoramento de Medicamentos/métodos , Neoplasias Colorretais/tratamento farmacológico , Alemanha/epidemiologia
3.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-516114

RESUMO

The ongoing COVID-19 pandemic has had great societal and health consequences. Despite the availability of vaccines, infection rates remain high due to immune evasive Omicron sublineages. Broad-spectrum antivirals are needed to safeguard against emerging variants and future pandemics. We used mRNA display under a reprogrammed genetic code to find a spike-targeting macrocyclic peptide that inhibits SARS-CoV-2 Wuhan strain infection and also pseudoviruses containing spike proteins of SARS-CoV-2 variants or related sarbecoviruses. Structural and bioinformatic analyses reveal a conserved binding pocket between the receptor binding domain and other domains, distal to the ACE2 receptor-interaction site. Collectively, our data reveal a hitherto unexplored site of vulnerability in sarbecoviruses that can be targeted by peptides and potentially other drug-like molecules. One-Sentence SummaryWe identify a conserved site on the SARS-CoV-2 spike that can be targeted by a broadly neutralizing macrocyclic peptide.

4.
Sci Rep ; 10(1): 11821, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678308

RESUMO

Link travel speeds in road networks are essential data for a variety of research problems in logistics, transportation, and traffic management. Real-world link travel speeds are stochastic, and highly dependent on speeds in previous time periods and neighboring road links. To understand how link travel speeds vary over space and time, we uncover their distributions, their space- and/or time-dependent correlations, as well as partial correlations, based on link travel speed datasets from an urban road network and a freeway network. We find that more than 90% (57%) of travel speeds are normally distributed in the urban road (freeway) network, and that correlations generally decrease with increased distance in time and space. We also investigate if and how different types of road links affect marginal distributions and correlations. The results show that different road link types produce quite similar marginal distributions and correlations. Finally, we study marginal distributions and correlations in a freeway network. Except that the marginal distribution and time correlation are different from the urban road network, others are similar.

5.
Chemosphere ; 256: 126968, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32428738

RESUMO

The recycling of nutrients from wastewater and their recovery in the form of valuable products is an effective strategy to accelerate the circular economy concept. Phosphorus recovery from wastewater by struvite crystallization (MgNH4PO4·6H2O) is one of the most applied techniques to compensate for the increasing demand and to slow down the depletion rate of phosphate rocks. Using low-cost magnesium sources, such as seawater, improves the financial sustainability of struvite production. In this study, the potential of seawater for struvite crystallization versus the commonly used magnesium source, MgCl2, was tested by crystal growth and kinetic experiments. The impact of ammonium concentration, magnesium concentration and pH on the growth kinetics of struvite in synthetic and real reject water were studied. The results showed that simultaneous precipitation of calcium phosphate was insignificant when using seawater, while presence of struvite seeds diminished it further. Among the supersaturation regulators, pH had the most significant effect on the struvite growth with both MgCl2 and seawater, while high N:P molar ratios further improved the struvite crystal growth by seawater. The N:P molar ratios higher than 6 and Mg:P molar ratios higher than 0.2 are recommended to improve the crystal growth kinetics. It was concluded that seawater is a promising alternative magnesium source and the control of supersaturation regulators (i.e., Mg:P, N:P and pH) is an effective strategy to control the reaction kinetics and product properties.


Assuntos
Modelos Químicos , Água do Mar/química , Estruvita/química , Fosfatos de Cálcio , Cristalização , Cinética , Magnésio/química , Cloreto de Magnésio/química , Compostos de Magnésio/química , Minerais , Fosfatos/química , Fósforo/química , Reciclagem , Águas Residuárias/química
6.
Surgery ; 168(2): 297-304, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32139142

RESUMO

BACKGROUND: Historically, adults with ultra short bowel syndrome (USBS) have been considered candidates for lifetime parenteral nutrition (PN) or are referred for visceral transplantation. We examined the surgical and nutritional outcomes of adult patients with USBS managed at a single intestinal rehabilitation center. METHODS: We retrospectively reviewed data on 588 adult patients referred to our center between January 2013 and December 2018. USBS was defined as residual small bowel (SB) length ≤ 50 cm. RESULTS: Forty-five patients (7.6%) with a mean age of 46.7 years (range 17-78) were identified. Indications for enterectomy included mesenteric ischemia (n=17) and internal hernias (n=6), followed by large intraabdominal fibroids, trauma, and allograft enterectomies, with five cases each. Median SB length was 18.0 cm; 20 patients (44.4%) had their entire SB resected. Thirteen patients had an intact colon, of which nine had preservation of the ileocecal valve. Patients who underwent autologous reconstruction of their gastrointestinal (GI) tract required a lower total PN volume (29.0 ± 7.6 vs. 40.8 ± 13.2 ml/Kg/day, p=0.002) and presented better short- and long- term survival (p=0.005). Patients with no gut had higher mortality (p=0.036). Hormonal therapy with the glucagon-like peptide-2 analog teduglutide was used in nine patients (20%) five of whom were weaned off TPN. Excluding patients with no gut (n=20), discontinuation of total PN rate for patients with an end ostomy or tube decompression (n= 6), jejunocolostomy (n= 10), and jejunoileostomy (n=9) were 0%, 40%, and 77.7%, respectively. Eleven patients (44%) with some residual small intestine achieved nutritional autonomy in an average of 20 months after GI reconstruction. Fifteen patients were listed for transplantation (33.3%). Seven patients underwent isolated SB transplantation and achieved nutritional autonomy in an average of three months after transplantation. One-year patient and graft survival were 100%. After a 37-month median follow-up period, 36 of 42 patients followed by our center were still alive (85.7%). CONCLUSION: Nutritional autonomy can be achieved in a significant number of patients with USBS in specialized centers with surgical and/or hormonal therapy. The presence of an intact colon and ileocecal valve can significantly increase the adaptation rate. Moreover, restoration of GI tract continuity has a positive impact on medical management and survival.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Síndrome do Intestino Curto/cirurgia , Adolescente , Adulto , Idoso , Algoritmos , Feminino , Fármacos Gastrointestinais/uso terapêutico , Humanos , Intestino Delgado/transplante , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Nutrição Parenteral Total , Peptídeos/uso terapêutico , Estudos Retrospectivos , Transplantados/estatística & dados numéricos , Adulto Jovem
7.
Water Res ; 173: 115572, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062222

RESUMO

Seawater, as an alternative magnesium source, has the potential to improve the overall economics and environmental footprint of struvite production compared to the use of pure magnesium salts. However, the dilution effect and the presence of other ions in seawater can reduce the phosphorus recovery potential and the simultaneous precipitation of other compounds may reduce the quality of the produced struvite. This work presents a comparative study of seawater and MgCl2 by performing a series of thermodynamic equilibrium modeling and crystallization experiments. The results revealed that acceptable phosphorus recovery (80-90%) is achievable by using seawater as the magnesium source for struvite precipitation. Further, the simultaneous precipitation of calcium phosphates was successfully controlled and minimized by optimum selection of reaction pH and seawater volume (i.e. Mg:P and Mg:Ca molar ratios). The increase of temperature from 20 °C to 30 °C reduced the phosphorus recovery by 15-20% while it increased the particle size by 30-35%. The presence of suspended solids in reject water did not have significant effects on phosphorus recovery but it made the struvite separation difficult as the obtained struvite was mixed with suspended solids. The experimental results and economic evaluation showed that the use of seawater can reduce the chemical costs (30-50%) and the CO2-footprint (8-40%) of struvite production. It was concluded that seawater is a potential alternative to pure magnesium sources in struvite production, while studies in larger scale and continuous mode are needed for further verification before full-scale applications.


Assuntos
Compostos de Magnésio , Fósforo , Precipitação Química , Cristalização , Fosfatos , Água do Mar , Estruvita , Eliminação de Resíduos Líquidos
8.
Water Res ; 171: 115377, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31841957

RESUMO

Despite the advantage of model-based design, anaerobic digesters are seldom designed using biokinetic models due to lack of reliable kinetic coefficients and/or systematic approaches for incorporating kinetic models into digester design. This study presents a systematic framework, which couples practical identifiability, uncertainty quantification and attainable region (AR) concepts for defining process performance targets, especially when reliable kinetic coefficients are unavailable. Within the framework, we introduce the concept of self-optimizing ARs, which define performance targets that results in near optimal operation in spite of variations in kinetic coefficients. Using the case of modified Hill model, only 3 out of the 6 model parameters (unidentifiable set) are responsible for the model prediction uncertainty. The uncertainty bands (mean, 10th percentile and 90th percentile) on the model states has been computed using the Monte Carlo Simulation procedure and attainable regions for the different levels of uncertainty has been constructed and the boundaries interpreted into digester structures. The self-optimizing attainable regions have been defined as the intersection region of the attainable regions corresponding to the mean, 10th percentile and 90th percentile. Incorporating uncertainty significantly reduces performance targets of the process but increases self-optimality in defining performance targets. Unlike the attainable region, which represents the limits of achievability for defined kinetics, the self-optimizing attainable region represents the set of all possible states attainable by the system even in cases of kinetic uncertainty. In summary, the concept of self-optimizing ARs provides a systematic way of defining process performance targets and making economic decisions under conditions of uncertainty.


Assuntos
Anaerobiose , Método de Monte Carlo , Cinética , Incerteza
9.
Water Res ; 163: 114891, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31362216

RESUMO

Unlike high-rate anaerobic digesters that employ some mechanism to retain microbial sludge mass, low-rate systems use sufficiently long hydraulic retention times to ensure process stability, which becomes economically unattractive for treating large quantities of waste. This study presents the use of attainable region to develop a new strategy to enhance the stability of low-rate digesters. By considering three digestion cases, diary manure only (batch 1) or diary manure with granular (batch 2) or lagoon (batch) sludge as innoculum, the following findings were obtained. (1) For a given concentration of volatile acids in an anaerobic digester, higher concentrations of methanogenic archae can be attained using a digester structure (combination of different digesters) as opposed to single digester. (2) For a given digested substrate, a change in the source of inoculum results in a change in the limits of achievability by the system (attainable limits for batches 1, 2 and 3 were 46.486(g/L)2, 5.562(g/L)2 and 0.551(g/L)2, which resulted in performance improvements of 118.604%,175.627% and 200.436% respectively), and hence optimal digester structure. The evidence from this study suggests that the technique can be used to simultaneously improve process stability, define performance targets and propose digester structures required to achieve a given target.


Assuntos
Reatores Biológicos , Euryarchaeota , Anaerobiose , Esterco , Metano , Esgotos
10.
Water Sci Technol ; 79(9): 1777-1789, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31241483

RESUMO

The enhanced biological phosphorus removal process makes the phosphorus recovery feasible from the dewatering streams of biological sludge. The physicochemical properties of these sidestreams, as an input to a crystallizer, are different before and after anaerobic digestion. In this study, phosphorus recovery by calcium phosphate is proposed for pre-digestion sidestreams and by struvite precipitation for post-digestion sidestreams. The thermodynamic modeling followed by experimental tests was performed to evaluate the recovery efficiency and product properties of struvite and calcium phosphates. The variations in phosphorus recovery potential, reaction kinetics and particle size distribution emphasize the importance of the adjustment of initial supersaturation and pH of the reaction. The optimum pH, considering the economics and recovery efficiency, for both calcium phosphate and struvite precipitation was found to be pH = 8.5, whereas further increase of pH will not improve the overall efficiency of the process. In the case of calcium phosphate precipitation, it was shown that possible phase transformations should be considered and controlled as they affect both process efficiency and product properties. The economic evaluation indicated that the optimized operational condition should be determined for the phosphorus recovery process and that chemical costs for the production of calcium phosphates is lower than for struvite.


Assuntos
Fósforo/análise , Eliminação de Resíduos Líquidos/métodos , Precipitação Química , Compostos de Magnésio , Fosfatos , Esgotos , Estruvita
11.
Proc Natl Acad Sci U S A ; 116(9): 3508-3517, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30755520

RESUMO

Duchenne muscular dystrophy (DMD) is a genetic disorder caused by loss of the protein dystrophin. In humans, DMD has early onset, causes developmental delays, muscle necrosis, loss of ambulation, and death. Current animal models have been challenged by their inability to model the early onset and severity of the disease. It remains unresolved whether increased sarcoplasmic calcium observed in dystrophic muscles follows or leads the mechanical insults caused by the muscle's disrupted contractile machinery. This knowledge has important implications for patients, as potential physiotherapeutic treatments may either help or exacerbate symptoms, depending on how dystrophic muscles differ from healthy ones. Recently we showed how burrowing dystrophic (dys-1) C. elegans recapitulate many salient phenotypes of DMD, including loss of mobility and muscle necrosis. Here, we report that dys-1 worms display early pathogenesis, including dysregulated sarcoplasmic calcium and increased lethality. Sarcoplasmic calcium dysregulation in dys-1 worms precedes overt structural phenotypes (e.g., mitochondrial, and contractile machinery damage) and can be mitigated by reducing calmodulin expression. To learn how dystrophic musculature responds to altered physical activity, we cultivated dys-1 animals in environments requiring high intensity or high frequency of muscle exertion during locomotion. We find that several muscular parameters (e.g., size) improve with increased activity. However, longevity in dystrophic animals was negatively associated with muscular exertion, regardless of effort duration. The high degree of phenotypic conservation between dystrophic worms and humans provides a unique opportunity to gain insight into the pathology of the disease as well as the initial assessment of potential treatment strategies.


Assuntos
Distrofia Muscular Animal/terapia , Distrofia Muscular de Duchenne/terapia , Condicionamento Físico Animal , Esforço Físico/fisiologia , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/genética , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos mdx , Contração Muscular/fisiologia , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/fisiopatologia , Distrofia Muscular Animal/genética , Distrofia Muscular Animal/fisiopatologia , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/fisiopatologia , Esforço Físico/genética
12.
Water Res ; 88: 643-652, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26575473

RESUMO

The reactivity of dissolved effluent organic matter (EfOM) in the process of ozonation was examined. Under different ozone dosages (0.42 ± 0.09, 0.98 ± 0.11 and 2.24 ± 0.17 mgO3/mg DOC), the EfOM before and after ozonation could be classified into four fractions according to their hydrophobicities. By ozonation, the hydrophobic fractions, especially hydrophobic acid (HOA) and hydrophobic neutral (HON), were found to undergo a process of transformation into hydrophilic fractions (HI), of which the HOA were first transformed into HON, and then the majority of the HON fraction was later converted to HI by further ozonation. It was noticeable that after ozonation, the fluorescence intensity in the humic-like and protein-like regions decreased as indicated by the excitation and emission matrix (EEM) spectra for the hydrophobic fractions. By coupling the EEM spectra with the molecular size analysis using high performance size exclusion chromatography (HPSEC), the difference between the characteristic distributions of the humic-like and protein-like fluorophores were further revealed. It could thus be extrapolated that ozone might have preferentially reacted with the protein-like hydrophobic fraction with molecular weight (MW) less than 100 kDa. Moreover, by X-ray photoelectron spectroscopy (XPS) analysis, it was identified that with increasing ozone dosage (from 0 to 2.24 ± 0.17 mgO3/mg DOC), the aromaticity of HON decreased dramatically, while aliphatics and ketones increased especially at the low ozone dose (0.42 ± 0.09 mgO3/mg DOC). Of the EfOM fractions, the HON fraction would have a higher content of electron enriched aromatics which could preferentially react with ozone rather than the HOA fraction.


Assuntos
Substâncias Húmicas/análise , Ozônio/química , Eliminação de Resíduos Líquidos , Águas Residuárias/análise , Poluentes Químicos da Água/química , Cromatografia em Gel , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia Fotoeletrônica
13.
Ultraschall Med ; 32 Suppl 2: E169-74, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21630183

RESUMO

PURPOSE: To determine the intraobserver and interobserver reliability of transvaginal ultrasound measurements of cervical length and quantitative ultrasonic tissue characterization (QUTC). MATERIALS AND METHODS: 20 healthy women in the second and third trimester of pregnancy underwent transvaginal ultrasound examination of the cervix by two sonographers. 3 replicate vaginal measurements of cervical length and QUTC were taken by each observer for each woman. The repeatability coefficient and intraclass correlation coefficient as well as the interclass correlation coefficient and limits of agreement were calculated. RESULTS: The reliability coefficient for transvaginal cervical length measurements was 0.95 for sonographer 1 and 0.99 for sonographer 2. The corresponding intraclass correlation coefficients for cervical length measurements were 0.872 and 0.973. The interclass correlation coefficient for transvaginal cervical length measurements was 0.986, the mean interobserver difference was -2 mm, and the limits of agreement were -5.4 mm to 1.5 mm. The reliability coefficients for QUTC were 0.90 (sonographer 1) and 0.97 (sonographer 2) and the corresponding intraclass correlation coefficients for cervical length measurements were 0.74 and 0.9. The interclass correlation coefficient was 0.56, the mean interobserver difference was 0.14, and the limits of agreement were -22.46 to 22.74. CONCLUSION: Transvaginal cervical length measurements showed a high intraobserver and interobserver reliability, while quantitative ultrasonic tissue characterization had poor interobserver reliability and should currently not be applied in clinical practice.


Assuntos
Medida do Comprimento Cervical/métodos , Colo do Útero/diagnóstico por imagem , Endossonografia/métodos , Interpretação de Imagem Assistida por Computador , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Ultrassonografia Pré-Natal , Algoritmos , Feminino , Humanos , Variações Dependentes do Observador , Trabalho de Parto Prematuro/diagnóstico por imagem , Gravidez , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Risco , Software , Estatística como Assunto , Vagina/diagnóstico por imagem
14.
Eur J Cancer ; 47(4): 640-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21216589

RESUMO

The breast cancer resistance protein ABCG2 confers cellular resistance to irinotecan (CPT-11) and its active metabolite SN-38. We utilised ABCG2-expressing xenografts as a model to evaluate the ability of a non-toxic ABCG2 inhibitor to increase intracellular drug accumulation. We assessed the activity of irinotecan in vivo in SCID mice: irinotecan completely inhibited the development of control pcDNA3.1 xenografts, whilst only delaying the growth of ABCG2-expressing xenografts. Addition of MBLI-87, an acridone derivative inhibitor, significantly increased the irinotecan effect against the growth of ABCG2-expressing xenografts. In vitro, MBLI-87 was as potent as GF120918 against ABCG2-mediated irinotecan efflux, and additionally was specific for ABCG2. A significant sensitisation to irinotecan was achieved despite the fact that doses remained well below the maximum tolerated dose (due to the rather limited solubility of MBLI-87). This suggested that MBLI-87 is an excellent candidate to prevent drug efflux by ABCG2, without altering plasma concentrations of irinotecan and SN-38 after IP (intra-peritoneal) injections. This could constitute a useful strategy to improve drug pharmacology, to facilitate drug penetration into normal tissue compartments protected by ABCG2, and potentially to reverse drug resistance in cancer cells.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Acridinas/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Camptotecina/análogos & derivados , Proteínas de Neoplasias/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Acridonas/farmacologia , Animais , Antineoplásicos Fitogênicos/metabolismo , Camptotecina/metabolismo , Camptotecina/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Células HEK293 , Humanos , Irinotecano , Camundongos , Camundongos SCID , Proteínas de Neoplasias/antagonistas & inibidores , Transplante de Neoplasias , Transplante Heterólogo
15.
Z Geburtshilfe Neonatol ; 215(6): 241-5, 2011 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-22274934

RESUMO

INTRODUCTION: The aim of this clinical study was to define foetal cardiac volumetry utilising 3D ultrasound. METHOD: 3D volumetry was performed in 131 cases. Cardiac output and stroke volume were calculated. Cardiac output and stroke volume of the right and left ventricles were defined in relation to foetal weight and gestational age in weeks. RESULTS: The mean value for foetal cardiac output was 393.68 mL/min. A progredient rise was detected with increasing gestational age. The mean values were 215.12 mL/min in the 28th week, 315.99 mL/min in the 32nd week, 464.14 mL/min in the 36th week and 681.77 mL/min at term. In relation to body weight (kg), the cardiac output was higher at 28 weeks (252.24 mL/min/kg) as compared with later in gestation, namely 208.91 mL/min/kg at term. CONCLUSION: It is technically feasible to calculate foetal cardiac volumes by means of 3D ultrasound. While the overall cardiac output of the foetus is high, it decreases in relation to body weight at the end of gestation.


Assuntos
Débito Cardíaco , Ecocardiografia Tridimensional/métodos , Ultrassonografia Pré-Natal/métodos , Feminino , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Volume Sistólico
16.
Vox Sang ; 99(2): 177-92, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20331536

RESUMO

Prophylactic anti-D is a very safe and effective therapy for the suppression of anti-D immunization and thus prevention of haemolytic disease of the foetus and newborn. However, migration from countries with low health standards and substantial cuts in public health expenses have increased the incidence of anti-D immunization in many "developed" countries. Therefore, this forum focuses on prenatal monitoring standards and treatment strategies in pregnancies with anti-D alloimmunization. The following questions were addressed, and a response was obtained from 12 centres, mainly from Europe.


Assuntos
Antígenos de Grupos Sanguíneos/imunologia , Isoanticorpos/administração & dosagem , Complicações Hematológicas na Gravidez/terapia , Isoimunização Rh/terapia , Sistema do Grupo Sanguíneo Rh-Hr/imunologia , Feminino , Sangue Fetal/imunologia , Hemoglobina Fetal/análise , Humanos , Isoanticorpos/sangue , Isoanticorpos/imunologia , Gravidez , Complicações Hematológicas na Gravidez/sangue , Complicações Hematológicas na Gravidez/imunologia , Complicações Hematológicas na Gravidez/prevenção & controle , Isoimunização Rh/imunologia , Isoimunização Rh/prevenção & controle , Imunoglobulina rho(D)
17.
BJOG ; 117(6): 722-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20175873

RESUMO

OBJECTIVE: The aim of the study was to determine the sensitivity, specificity and accuracy of noninvasive tests for the fetal rhesus CcEc (RHCE) alleles C, c and E in early pregnancy. DESIGN: A prospective clinical trial was carried out to evaluate diagnostic accuracy. SETTING: Women were recruited at four centres specialising in prenatal diagnosis. Peripheral blood and amniotic fluid samples were obtained and sent to a single laboratory for analysis. SAMPLE: A total of 233 tests (46 for C, 87 for c and 100 for E) were performed on 181 specimens obtained from pregnant women at weeks 12 to 28 (median week 16) of gestation. METHODS: Following automated extraction of fetal DNA from maternal plasma, two different real-time polymerase chain reaction (PCR) protocols were used for the detection of the C, c and E alleles of RHCE. The results of the PCR were compared with genotyping results for the amniotic fluid. MAIN OUTCOME MEASURES: Failure rate, sensitivity, specificity and accuracy were the main outcome measures. RESULTS: Unequivocal results were obtained for all specimens. With the first PCR protocol, the sensitivity was 100% for C, 38% for c and 59% for E. In contrast, with the second protocol, the sensitivity for C, c and E was 100%. The specificity for all assays was found to be between 99% and 100%. CONCLUSIONS: A highly accurate protocol has been identified for the detection of fetal RHCE alleles in maternal plasma in early pregnancy. This noninvasive approach can be considered as a useful test in the management of pregnancies with anti-c, anti-E or anti-C alloimmunisation.


Assuntos
Reação em Cadeia da Polimerase/métodos , Diagnóstico Pré-Natal/métodos , Isoimunização Rh/diagnóstico , Sistema do Grupo Sanguíneo Rh-Hr/genética , Adolescente , Adulto , Feminino , Marcadores Genéticos/genética , Genótipo , Humanos , Pessoa de Meia-Idade , Fenótipo , Reação em Cadeia da Polimerase/normas , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Diagnóstico Pré-Natal/normas , Isoimunização Rh/embriologia , Sensibilidade e Especificidade , Adulto Jovem
20.
Z Geburtshilfe Neonatol ; 213(5): 180-5, 2009 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-19856240

RESUMO

BACKGROUND: Although foetal macrosomia is a known risk factor for shoulder dystocia, foetal weight estimation by ultrasound is imprecise. METHODS: We analysed in a retrospective, single-centre study whether the combination of foetal sonographic parameters and maternal parameters could improve the prediction of foetal macrosomia and whether on the basis of this findings the prediction of shoulder dystocia in foetal macrosomia could be enhanced. Likelihood ratios for sonographic parameters have been assessed and have been used to calculate post-test-probabilities for fetal macrosomia. All vaginal singleton deliveries with cephalic presentation >or=37+0 week of gestation in the period 1994-2005 (n=8 576) have been analysed. Shoulder dystocia has been observed in 136 cases (1.6%). RESULTS: In multivariate analysis the strongest predictor for shoulder dystocia was foetal macrosomia (>or= 4000 g), odds ratio=4.04 (95% confidence interval 2.71-6.05), next to diabetes 2.43 (1.14-5.17), obesity (BMI >or=30 kg/m (2)) 1.55 (1.02-2.46), and foetal head circumference (>35 cm) 1.51 (1.02-2.24). Foetal sonographic parameters showed likelihood ratios up to 6.93. The accuracy of shoulder dystocia predictions in cases of birth weight >or=4,500 g improved only slightly from 0.2-3.3%. DISCUSSION: The accuracy of the estimation of foetal macrosomia has been improved by combining ultrasonography with prepartal maternal risk factors.


Assuntos
Traumatismos do Nascimento/diagnóstico , Traumatismos do Nascimento/etiologia , Distocia/diagnóstico , Distocia/epidemiologia , Peso Fetal , Lesões do Ombro , Ultrassonografia Pré-Natal/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Gravidez , Prognóstico , Reprodutibilidade dos Testes , Medição de Risco/métodos , Fatores de Risco , Sensibilidade e Especificidade
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