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1.
BJOG ; 130(8): 881-890, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36808862

RESUMEN

OBJECTIVE: Deceleration area (DA) and capacity (DC) of the fetal heart rate can help predict risk of intrapartum fetal compromise. However, their predictive value in higher risk pregnancies is unclear. We investigated whether they can predict the onset of hypotension during brief hypoxaemia repeated at a rate consistent with early labour in fetal sheep with pre-existing hypoxaemia. DESIGN: Prospective, controlled study. SETTING: Laboratory. SAMPLE: Chronically instrumented, unanaesthetised near-term fetal sheep. METHODS: One-minute complete umbilical cord occlusions (UCOs) were performed every 5 minutes in fetal sheep with baseline pa O2 <17 mmHg (hypoxaemic, n = 8) and >17 mmHg (normoxic, n = 11) for 4 hours or until arterial pressure fell <20 mmHg. MAIN OUTCOME MEASURES: DA, DC and arterial pressure. RESULTS: Normoxic fetuses showed effective cardiovascular adaptation without hypotension and mild acidaemia (lowest arterial pressure 40.7 ± 2.8 mmHg, pH 7.35 ± 0.03). Hypoxaemic fetuses developed hypotension (lowest arterial pressure 20.8 ± 1.9 mmHg, P < 0.001) and acidaemia (final pH 7.07 ± 0.05). In hypoxaemic fetuses, decelerations showed faster falls in FHR over the first 40 seconds of UCOs but the final deceleration depth was not different to normoxic fetuses. DC was modestly higher in hypoxaemic fetuses during the penultimate (P = 0.04) and final (P = 0.012) 20 minutes of UCOs. DA was not different between groups. CONCLUSION: Chronically hypoxaemic fetuses had early onset of cardiovascular compromise during labour-like brief repeated UCOs. DA was unable to identify developing hypotension in this setting, while DC only showed modest differences between groups. These findings highlight that DA and DC thresholds need to be adjusted for antenatal risk factors, potentially limiting their clinical utility.


Asunto(s)
Acidosis , Hipotensión , Animales , Femenino , Embarazo , Acidosis/etiología , Feto , Frecuencia Cardíaca Fetal/fisiología , Hipotensión/complicaciones , Hipoxia/complicaciones , Estudios Prospectivos , Ovinos , Cordón Umbilical/irrigación sanguínea
2.
Eur Rev Med Pharmacol Sci ; 26(17): 6310-6315, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36111932

RESUMEN

OBJECTIVE: The pathogenesis of the inflammatory bowel disease (IBD) includes chronic inflammation and altered immune reactions. There are several publications, reporting that micro ribonucleic acids (miRNAs) may serve as a diagnostic biomarker with a potential to assess inflammation severity and treatment response1,2 in IBD patients. The objective of the study is to assess and correlate the serum expression of circulating miR-16 in IBD patients with some clinical parameters, such as extent, activity and severity of the disease. PATIENTS AND METHODS: 70 IBD patients [35 with ulcerative colitis (UC) and 35 with Crohn's disease (CD)] were included in the study. Serum miR-16 expression in both IBD diseases was assessed using reverse transcription quantitative real time PCR (RT-qPCR). Circulating miR-16 levels were also correlated with disease extent, activity and severity indices [Crohn's Disease Activity Index (CDAI), Montreal classification, Partial Mayo score]. Serum expression of miR-16 in the 70 patients was also compared to miR-16 serum levels in 30 healthy control subjects. RESULTS: The patients' group showed mean serum miR-16 expression of 3.07 for CD, 1.97 for UC and 1.61 for the control group of healthy subjects with a significant difference in the expression between groups. There is a significant correlation between increased serum expression of miR-16 and disease activity, extent and severity. CONCLUSIONS: The increased miR-16 serum expression correlates with disease activity, intestinal localization of CD, stenotic and penetrating phenotype. MiR-16 could serve as a potential biomarker to assess inflammation.


Asunto(s)
MicroARN Circulante , Colitis Ulcerosa , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , MicroARNs , Biomarcadores , Bulgaria , MicroARN Circulante/genética , MicroARN Circulante/metabolismo , Estudios de Cohortes , Colitis Ulcerosa/genética , Colitis Ulcerosa/metabolismo , Enfermedad de Crohn/genética , Enfermedad de Crohn/metabolismo , Humanos , Inflamación , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/metabolismo , MicroARNs/genética , MicroARNs/metabolismo
3.
Eur Rev Med Pharmacol Sci ; 26(7): 2399-2407, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35442494

RESUMEN

OBJECTIVE: Although the use of anti-tumor necrosis factor-alpha (anti-TNF-α) agents is highly effective in achieving and maintaining remission in patients with moderate-to-severe IBD, they place the patient at increased risk of developing opportunistic infections, including new cases of tuberculosis infection (TBI) and/or reactivation of latent tuberculosis infection (LTBI). Our study aims to determine the incidence of TBI [active tuberculosis (ATBI) and LTBI] among patients with Crohn's disease (CD) receiving anti-TNF-α therapy. PATIENTS AND METHODS: We performed a retrospective analysis of consecutive CD patients undergoing anti-TNF-α (infliximab, adalimumab) treatment for a minimum of 6 months, in the period between June 2010 and December 2019, followed-up at a reference IBD center. All patients were HIV negative, and BCG vaccinated. In all patients, ATBI was excluded and all were tested for LTBI prior to initiating a biological treatment. RESULTS: Before starting the biological treatment, we established LTBI in 11/109 (10.1%): 8/11 (72.7%) patients were TST positive, 2/11 (18.2%) were IGRA positive and TST negative, 1/11 (9.1%) were both IGRA and TST positive. In patients undergoing biological therapy with previous negative screening test for tuberculosis, a total of 16/74 (21.6%) patients were newly diagnosed with LTBI. The median induration (not erythema) diameter of TST is 8 (IQR 5-17) mm. Active pulmonary tuberculosis infection, developed in 3/74 (4.1%) patients. One patient developed ATBI on the background of chemoprophylaxis with INH for LTBI. CONCLUSIONS: Specialists should thoroughly analyse all patient clinical data, chest X-ray results, epidemiological and BCG status, as well as perform a LTBI screening before initiating immunosuppressive and/or biological treatment. IBD patients have a higher risk of developing TBI in the first 12 months.


Asunto(s)
Enfermedad de Crohn , Tuberculosis Latente , Tuberculosis , Vacuna BCG/uso terapéutico , Bulgaria , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/epidemiología , Humanos , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/epidemiología , Estudios Retrospectivos , Prueba de Tuberculina , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Inhibidores del Factor de Necrosis Tumoral , Factor de Necrosis Tumoral alfa/uso terapéutico
4.
Helminthologia ; 59(3): 217-225, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36694833

RESUMEN

The Nurse cell of the parasitic nematode Trichinella spiralis is a unique structure established after genetic, morphological and functional modification of a small portion of invaded skeletal muscle fiber. Even if the newly developed cytoplasm of the Nurse cell is no longer contractile, this structure remains well integrated within the surrounding healthy tissue. Our previous reports suggested that this process is accompanied by an increased local biosynthesis of sialylated glycoproteins. In this work we examined the expressions of three proteins, functionally associated with the process of sialylation. The enzyme UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) is a key initiator of the sialic acid biosynthetic pathway. The α-dystroglycan was the only identified sialylated glycoprotein in skeletal muscles by now, bearing sialyl-α-2,3-Gal-ß-1,4-Gl-cNAc-ß-1,2-Man-α-1-O-Ser/Thr glycan. The third protein of interest for this study was the enzyme ß-galactoside α-2,3-sialyltransferase 6 (ST3Gal6), which transfers sialic acid preferably onto Gal-ß-1,4-GlcNAc as an acceptor, and thus it was considered as a suitable candidate for the sialylation of the α-dystroglycan. The expressions of the three proteins were analyzed by real time-PCR and immunohistochemistry on modified methacarn fixed paraffin tissue sections of mouse skeletal muscle samples collected at days 0, 14 and 35 post infection. According to our findings, the up-regulation of GNE was a characteristic of the early and the late stage of the Nurse cell development. Additional features of this process were the elevated expressions of α-dystroglycan and the enzyme ST3Gal6. We provided strong evidence that an increased local synthesis of sialic acids is a trait of the Nurse cell of T. spiralis, and at least in part due to an overexpression of α-dystroglycan. In addition, circumstantially we suggest that the enzyme ST3Gal6 is engaged in the process of sialylation of the major oligosaccharide component of α-dystroglycan.

5.
BJOG ; 128(9): 1433-1442, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33369871

RESUMEN

OBJECTIVE: Cardiotocography is widely used to assess fetal well-being during labour. The positive predictive value of current clinical algorithms to identify hypoxia-ischaemia is poor. In experimental studies, fetal hypotension is the strongest predictor of hypoxic-ischaemic injury. Cohort studies suggest that deceleration area and deceleration capacity of the fetal heart rate trace correlate with fetal acidaemia, but it is not known whether they are indices of fetal arterial hypotension. DESIGN: Prospective, controlled study. SETTING: Laboratory. SAMPLE: Near-term fetal sheep. METHODS: One minute of complete umbilical cord occlusions (UCOs) every 5 minutes (1:5 min, n = 6) or every 2.5 minutes (1:2.5 min, n = 12) for 4 hours or until fetal mean arterial blood pressure fell <20 mmHg. MAIN OUTCOME MEASURES: Deceleration area and capacity during the UCO series were related to evolving hypotension. RESULTS: The 1:5 min group developed only mild metabolic acidaemia, without hypotension. By contrast, 10/12 fetuses in the 1:2.5-min group progressively developed severe metabolic acidaemia and hypotension, reaching 16.8 ± 0.9 mmHg after 71.2 ± 6.7 UCOs. Deceleration area and capacity remained unchanged throughout the UCO series in the 1:5-min group, but progressively increased in the 1:2.5-min group. The severity of hypotension was closely correlated with both deceleration area (P < 0.001, R2  = 0.66, n = 18) and capacity (P < 0.001, R2  = 0.67, n = 18). Deceleration area and capacity predicted development of hypotension at a median of 103 and 123 minutes before the final occlusion, respectively. CONCLUSIONS: Both deceleration area and capacity were strongly associated with developing fetal hypotension, supporting their potential to improve identification of fetuses at risk of hypotension leading to hypoxic-ischaemic injury during labour. TWEETABLE ABSTRACT: Deceleration area and capacity of fetal heart rate identify developing hypotension during labour-like hypoxia.


Asunto(s)
Cardiotocografía/métodos , Frecuencia Cardíaca Fetal/fisiología , Cordón Umbilical/irrigación sanguínea , Animales , Femenino , Humanos , Hipoxia-Isquemia Encefálica/prevención & control , Trabajo de Parto , Embarazo , Estudios Prospectivos , Ovinos
6.
Nanotechnology ; 30(28): 284003, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-30913546

RESUMEN

In this paper, micro-Raman mapping and conductive atomic force microscopy (C-AFM) were jointly applied to investigate the structural and electrical homogeneity of quasi-free-standing monolayer graphene (QFMLG), obtained by high temperature decomposition of 4H-SiC(0001) followed by hydrogen intercalation at 900 °C. Strain and doping maps, obtained by Raman data, showed the presence of sub-micron patches with reduced hole density correlated to regions with higher compressive strain, probably associated with a locally reduced hydrogen intercalation. Nanoscale resolution electrical maps by C-AFM also revealed the presence of patches with enhanced current injection through the QFMLG/SiC interface, indicating a locally reduced Schottky barrier height (ΦB). The ΦB values evaluated from local I-V curves by the thermionic emission model were in good agreement with the values calculated for the QFMLG/SiC interface using the Schottky-Mott rule and the graphene holes density from Raman maps. The demonstrated approach revealed a useful and non-invasive method to probe the structural and electrical homogeneity of QFMLG for future nano-electronics applications.

7.
Phys Chem Chem Phys ; 20(26): 17751-17761, 2018 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-29915819

RESUMEN

Metal organic chemical vapor deposition (MOCVD) of group III nitrides on graphene heterostructures offers new opportunities for the development of flexible optoelectronic devices and for the stabilization of conceptually-new two-dimensional materials. However, the MOCVD of group III nitrides is regulated by an intricate interplay of gas-phase and surface reactions that are beyond the resolution of experimental techniques. We use density-functional ab initio molecular dynamics (AIMD) with van der Waals corrections to identify atomistic pathways and associated electronic mechanisms driving precursor/surface reactions during metal organic vapor phase epitaxy at elevated temperatures of aluminum nitride on graphene, considered here as model case study. The results presented provide plausible interpretations of atomistic and electronic processes responsible for delivery of Al, C adatoms, and C-Al, CHx, AlNH2 admolecules on pristine graphene via precursor/surface reactions. In addition, the simulations reveal C adatom permeation across defect-free graphene, as well as exchange of C monomers with graphene carbon atoms, for which we obtain rates of ∼0.3 THz at typical experimental temperatures (1500 K), and extract activation energies E = 0.28 ± 0.13 eV and attempt frequencies Aexc = 2.1 (×1.7±1) THz via Arrhenius linear regression. The results demonstrate that AIMD simulations enable understanding complex precursor/surface reaction mechanisms, and thus propose AIMD to become an indispensable routine prediction-tool toward more effective exploitation of chemical precursors and better control of MOCVD processes during synthesis of functional materials.

8.
Physiol Meas ; 37(12): 2245-2259, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27883332

RESUMEN

Phase rectified signal averaging (PRSA) is increasingly used for fetal heart rate (FHR) monitoring, both with traces acquired with external Doppler cardiotocography (D-FHR), and with transabdominal fetal electrocardiography (ta-FHR). However, it is unclear to what extend the acquisition method influences the PRSA analysis, whether results from using one acquisition method are comparable to those based on FHR acquired by the other method, and if not, which should be the preferred method. To address these questions, we applied PRSA analysis to 28 antepartum synchronous recordings of the FHR using simultaneously D-FHR and ta-FHR. The data included late-onset intrauterine growth restricted (IUGR) fetuses (n = 20) and non-IUGR fetuses (n = 8), all of them at gestation ⩾34 weeks. PRSA analysis depends on two parameters intrinsic to the algorithm, T and S. We analyzed the data using parameters that included all values adopted by other researchers previously (derived from a literature search in PubMed and Google Scholar). T and S were adjusted for the difference in acquisition techniques. We found that the correlation between PRSA analysis based on D-FHR and ta-FHR decreased with decreasing values of the PRSA parameters T and S. Therefore, the acquisition technique affects PRSA values for high resolution PRSA (low values of T and S). In conclusion, for low resolution PRSA, the results from both acquisition methods are comparable. Because ta-FHR signals provide beat to beat data and thus capture more subtle differences in the heart rate variation than D-FHR signals (pre-processed by commercial monitors), we assumed that ta-FHR may provide potentially valuable extra information compared to D-FHR. However, no parameter settings or acquisition method seemed to have a diagnostic value for identifying the late-onset IUGR babies in our dataset.


Asunto(s)
Frecuencia Cardíaca Fetal , Procesamiento de Señales Asistido por Computador , Algoritmos , Cardiotocografía , Electrocardiografía , Femenino , Humanos , Embarazo , Estudios Retrospectivos
9.
Nanotechnology ; 27(14): 145601, 2016 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-26902955

RESUMEN

Graphite-like hexagonal AlN (h-AlN) multilayers have been experimentally manifested and theoretically modeled. The development of any functional electronics applications of h-AlN would most certainly require its integration with other layered materials, particularly graphene. Here, by employing vdW-corrected density functional theory calculations, we investigate structure, interaction energy, and electronic properties of van der Waals stacking sequences of few-layer h-AlN with graphene. We find that the presence of a template such as graphene induces enough interlayer charge separation in h-AlN, favoring a graphite-like stacking formation. We also find that the interface dipole, calculated per unit cell of the stacks, tends to increase with the number of stacked layers of h-AlN and graphene.

10.
Nanotechnology ; 27(5): 055704, 2016 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-26752271

RESUMEN

First-principles calculations are employed to investigate structural, electronic and topological insulating properties of XBi (X = B, Al, Ga, and In) monolayers upon halogenation. It is known that Y-XBi (X = Ga, In, Tl; Y = F, Cl, Br, I) can originate inversion-asymmetric topological insulators with large bulk band gaps. Our results suggest that Y-XBi (X = B, Al; Y = F, Cl, Br, I) may also result in nontrivial topological insulating phases. Despite the lower atomic number of B and Al, the spin-orbit coupling opens a band gap of about 400 meV in Y-XBi (X = B, Al), exhibiting an unusual electronic behavior for practical applications in spintronics. The nature of the bulk band gap and Dirac-cone edge states in their nanoribbons depends on the group-III elements and Y chemical species. They lead to a chemical tunability, giving rise to distinct band inversion symmetries and exhibiting Rashba-type spin splitting in the valence band of these systems. These findings indicate that a large family of Y-XBi sheets can exhibit nontrivial topological characteristics, by a proper tuning, and open a new possibility for viable applications at room temperature.

11.
BJOG ; 123(12): 1955, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26704890

Asunto(s)
Monitoreo Fetal , Humanos
12.
J Phys Condens Matter ; 27(48): 485306, 2015 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26569356

RESUMEN

The band structure and stability of XBi and XBi3 (X = B, Al, Ga, and In) single sheets are predicted using first-principles calculations. It is demonstrated that the band gap values of these new classes of two-dimensional (2D) materials depend on both the spin-orbit coupling (SOC) and type of group-III elements in these hetero-sheets. Thus, topological properties can be achieved, allowing for viable applications based on coherent spin transport at room temperature. The spin-orbit effects are proved to be essential to explain the tunability by group-III atoms. A clear effect of including SOC in the calculations is lifting the spin degeneracy of the bands at the Γ point of the Brillouin zone. The nature of the band gaps, direct or indirect, is also tuned by SOC, and by the appropriate X element involved. It is observed that, in the case of XBi single sheets, band inversions naturally occur for GaBi and InBi, which exhibit band gap values around 172 meV. This indicates that these 2D materials are potential candidates for topological insulators. On the contrary, a similar type of band inversion, as obtained for the XBi, was not observed in the XBi3 band structure. In general, the calculations, taking into account SOC, reveal that some of these buckled sheets exhibit sizable gaps, making them suitable for applications in room-temperature spintronic devices.

13.
Dalton Trans ; 44(7): 3356-66, 2015 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-25599815

RESUMEN

We employ ab initio calculations to predict the equilibrium structure, stability, reactivity, and Raman scattering properties of sixteen different (H3C)nX(SiH3)3-n compounds (X = B, Al, Ga, In) with n = 0-3. Among this methylsilylmetal family, only the (H3C)3X members, i.e., trimethylboron (TMB), trimethylaluminum (TMA), trimethylgallium (TMG), and trimethylindium (TMI), are currently well-studied. The remaining twelve compounds proposed here open up a two-dimensional array of new possibilities for precursors in various deposition processes, and evoke potential applications in the chemical synthesis of other compounds. We infer that within the (H3C)nX(SiH3)3-n family, the compounds with fewer silyl groups (and consequently with more methyl groups) are less reactive and more stable. This trend is verified from the calculated cohesive energy, Gibbs free energy of formation, bond strength, and global chemical indices. Furthermore, we propose sequential reaction routes for the synthesis of (H3C)nX(SiH3)3-n by substitution of methyl by silyl groups, where the silicon source is the silane gas. The corresponding reaction barriers for these chemical transformations lie in the usual energy range typical for MOCVD processes. We also report the Raman spectra and light scattering properties of the newly proposed (H3C)nX(SiH3)3-n compounds, in comparison with available data of known members of this family. Thus, our computational experiment provides useful information for a systematic understanding of the stability/reactivity and for the identification of these compounds.

15.
BJOG ; 121(7): 889-94, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24842087

RESUMEN

OBJECTIVE: Recent studies suggest that phase-rectified signal averaging (PRSA), measured in antepartum fetal heart rate (FHR) traces, may sensitively indicate fetal status; however, its value has not been assessed during labour. We determined whether PRSA relates to acidaemia in labour, and compare its performance to short-term variation (STV), a related computerised FHR feature. DESIGN: Historical cohort. SETTING: Large UK teaching hospital. POPULATION: All 7568 Oxford deliveries that met the study criteria from April 1993 to February 2008. METHODS: We analysed the last 30 minutes of the FHR and associated outcomes of infants. We used computerised analysis to calculate PRSA decelerative capacity (DC(PRSA)), and its ability to predict umbilical arterial blood pH ≤ 7.05 using receiver operator characteristic (ROC) curves and event rate estimates (EveREst). We compared DC(PRSA) with STV calculated on the same traces. MAIN OUTCOME MEASURE: Umbilical arterial blood pH ≤ 7.05. RESULTS: We found that PRSA could be measured in all cases. DC(PRSA) predicted acidaemia significantly better than STV: the area under the ROC curve was 0.665 (95% CI 0.632-0.699) for DC(PRSA), and 0.606 (0.573-0.639) for STV (P = 0.007). EveREst plots showed that in the worst fifth centile of cases, the incidence of low pH was 17.75% for DC(PRSA) but 11.00% for STV (P < 0.001). DC(PRSA) was not highly correlated with STV. CONCLUSIONS: DC(PRSA) of the FHR can be measured in labour, and appears to predict acidaemia more accurately than STV. Further prospective evaluation is warranted to assess whether this could be clinically useful. The weak correlation between DC(PRSA) and STV suggests that they could be combined in multivariate FHR analyses.


Asunto(s)
Acidosis/sangre , Acidosis/fisiopatología , Cardiotocografía , Frecuencia Cardíaca Fetal/fisiología , Estudios de Cohortes , Femenino , Enfermedades Fetales/fisiopatología , Humanos , Embarazo , Estudios Retrospectivos
16.
Eur J Obstet Gynecol Reprod Biol ; 176: 112-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24655553

RESUMEN

OBJECTIVE: To investigate the effect of syntocinon augmentation on the fetal cardiotocogram (CTG) using computerised analysis. We hypothesised that syntocinon will have no direct effects on the fetal heart rate if used correctly. STUDY DESIGN: A retrospective, nested case-control study. SETTING: Intrapartum CTG records from the digital archive at the John Radcliffe Hospital, Oxford, UK. SUBJECTS: 110 women with singleton pregnancies of >36 weeks gestation, no known congenital abnormality, spontaneous onset of labour and syntocinon augmentation for failure to progress, with start time of syntocinon recorded, from between August 1998 and December 1999, extensively matched to 110 controls who had normally progressing labours. METHODS: Eight different CTG features were measured during four time points with OxSys, a computerised numerical analysis system. STATISTICAL ANALYSIS: Differences in the CTG features over time in cases and controls using ANOVA and Friedman's ANOVA and at each time point between case-control pairs using Student's t-test and the Wilcoxon signed rank test. RESULTS: After administration, syntocinon increased the frequency, decreased the duration and decreased the resting time between contractions (p<0.001), resulting in no significant difference between normally progressing labours and those requiring augmentation. The case group had a significantly higher signal stability index (SSI) and fewer decelerations compared to the control group - differences which disappeared after augmentation was commenced (p=0.025 and 0.033 respectively). Syntocinon did not affect the baseline heart rate, short term variability (STV) or phase rectified signal averaging (PRSA) (p=0.518, 0.215 and 0.138) in comparison with controls. There was a significant increase in the PRSA in babies born with acidaemia (arterial pH≤7.05) 60-120min after syntocinon was commenced that was not seen with in babies with a normal pH (p=0.002). CONCLUSION: Syntocinon "normalises" ineffective uterine activity without any direct effect on the fetal heart rate. Therefore its administration does not confound objective computerised analysis. There may be a specific response in PRSA shortly after commencing syntocinon augmentation in the fetus which is subsequently born acidaemic which requires further investigation.


Asunto(s)
Cardiotocografía/efectos de los fármacos , Frecuencia Cardíaca Fetal/efectos de los fármacos , Oxitocina/uso terapéutico , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Embarazo , Estudios Retrospectivos
17.
Bioorg Med Chem ; 22(2): 874-82, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24365391

RESUMEN

Novel polyphosphoesters containing anthracene-derived aminophosphonate units, poly(oxyethylene aminophosphonate)s (4 and 5) and poly[oxyethylene(aminophosphonate-co-H-phosphonate)]s (6 and 7), were synthesized via an addition of poly(oxyethylene H-phosphonate)s to 9-anthrylidene-p-toluidine. The IR, NMR ((1)H, (13)C and (31)P) and fluorescence emission spectral data of the polymers are presented. The copolymers 6 and 7 were tested for in vitro antitumor activity on a panel of seven human epithelial cancer cell lines. Safety testing was performed both in vitro (3T3 NRU test) and in vivo on ICR mice for genotoxicity and antiproliferative activity. The copolymer 7 showed excellent antiproliferative activity to HBL-100, MDA-MB-231, MCF-7 and HepG2 cell lines. However, the in vitro safety testing revealed significant toxicity to Balb/c 3T3 mouse embryo cells. In contrast, the copolymer 6 showed complete absence of cytotoxicity to Balb/c 3T3 cells, but inhibited the growth of breast cancer cells, cervical carcinoma cells (HeLa) and hepatocellular carcinoma cell cultures after prolonged (72h) exposure. The polymers (4-6) exhibited low (4 and 6) to moderate (5) clastogenicity in vivo and slightly inhibited bone marrow cell division, compared to Mitomycin C. The subcellular distribution of the copolymers 6 and 7 were studied in model cell culture systems. The tested polyphosphoesters are expected to act in vivo as prodrugs of aminophosphonates and could be valuable as a new class of biodegradable polymer drug carriers.


Asunto(s)
Antracenos/química , Antimitóticos/farmacología , Antineoplásicos/farmacología , Organofosfonatos/farmacología , Animales , Antimitóticos/administración & dosificación , Antimitóticos/síntesis química , Antineoplásicos/administración & dosificación , Antineoplásicos/síntesis química , Células 3T3 BALB , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células Hep G2 , Humanos , Células MCF-7 , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos ICR , Mitosis/efectos de los fármacos , Estructura Molecular , Organofosfonatos/administración & dosificación , Organofosfonatos/síntesis química , Relación Estructura-Actividad
18.
Med Biol Eng Comput ; 50(7): 717-25, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22678597

RESUMEN

Electronic fetal heart rates (FHR) are used to monitor fetal health during labour. The paper records are visually assessed by clinicians, but automated alternatives are being developed. Interpretation, visual or computerised, depends on assigning a baseline to identify key features such as accelerations and decelerations. However, when the FHR is unstable the baseline may be unassignable, making conventional analysis unreliable. Such instability may reflect on fetal health. If true, these segments should not be discarded but quantified, for which we have developed a numerical method. In 7,568 labours, the association between unassignable baseline and umbilical arterial blood pH ≤ 7.05 at birth (evidence of poor health) was studied retrospectively. We found a consistent increase of the risk for acidaemia with longer intervals of unassignable baseline. This is detectable at the end of the first stage of labour, but stronger at the end of the second stage: in the last 30 min of labour, the odds ratios (with respect to baseline assignable throughout this period) increased from 1.99 (15 min unassignable) to 4.9 (30 min unassignable). Computerised analysis of the FHR becomes unreliable when the baseline cannot be assigned; however, this pattern is itself a pathological feature associated with acidaemia at birth.


Asunto(s)
Monitoreo Fetal/métodos , Frecuencia Cardíaca Fetal/fisiología , Procesamiento de Señales Asistido por Computador , Acidosis/etiología , Femenino , Humanos , Recién Nacido , Trabajo de Parto , Embarazo , Pronóstico , Estudios Retrospectivos
19.
Artículo en Inglés | MEDLINE | ID: mdl-23366590

RESUMEN

A database of fetal heart rate (FHR) time series measured from 7 221 patients during labor is analyzed with the aim of learning the types of features of these recordings that are informative of low cord pH. Our 'highly comparative' analysis involves extracting over 9 000 time-series analysis features from each FHR time series, including measures of autocorrelation, entropy, distribution, and various model fits. This diverse collection of features was developed in previous work [1]. We describe five features that most accurately classify a balanced training set of 59 'low pH' and 59 'normal pH' FHR recordings. We then describe five of the features with the strongest linear correlation to cord pH across the full dataset of FHR time series. The features identified in this work may be used as part of a system for guiding intervention during labor in future. This work successfully demonstrates the utility of comparing across a large, interdisciplinary literature on time-series analysis to automatically contribute new scientific results for specific biomedical signal processing challenges.


Asunto(s)
Frecuencia Cardíaca Fetal/fisiología , Cardiotocografía , Femenino , Monitoreo Fetal , Humanos , Concentración de Iones de Hidrógeno , Embarazo
20.
Khirurgiia (Sofiia) ; (6): 52-4, 2010.
Artículo en Búlgaro | MEDLINE | ID: mdl-21972719

RESUMEN

The authors adopt in clinical practice using of sterile hygroscopic wound dressings 'pampers type'. They use these dressings in 113 patients. The appropriate patients are these with limbs amputations, diabetic foot, suppurative and plenty secreting deep wounds, atonite and decubital wounds. The dressings are sterilised using paraformaldehyde sterilization which do not injure the synthetic materials. The hygroscopic dressings are non- allergic and are well tolerated by the patients. Using these dressings facilitate the medical team work and help to reduce the contamination of the hospital linen and the patients coverlet. They help for accelerating the wound healing process. They are also economic effective by reducing the amount of used dressing material.


Asunto(s)
Amputación Quirúrgica , Vendajes/tendencias , Pie Diabético/terapia , Cicatrización de Heridas , Amputación Quirúrgica/métodos , Animales , Vendajes/economía , Perros , Formaldehído , Humanos , Polímeros , Conejos , Esterilización , Humectabilidad
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