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1.
Bioresour Technol ; 400: 130655, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38580168

RESUMEN

The emerging hydrothermal liquefaction (HTL) process is evaluated against the classical anaerobic digestion (AD) processes for stabilizing wastewater sludges and recovering their energy- and nutrient-contents. Although HTL affords faster stabilization, better process stability, and liquid fuel and sterile fertilizer recovery, it suffers from higher energy demand and lower technology readiness level. For a rational comparison of these pathways, a multi-criteria evaluation is conducted considering 21 technical, environmental, economic, and social criteria. Criteria values for the HTL-pathway were derived from laboratory tests while those for the AD-pathway were compiled from literature. Of the 16 process alternatives evaluated, the AD-pathway including nitrogen-recovery by air-stripping and phosphorus recovery by the MEPHREC® process ranked first followed by the HTL-pathway. This multi-criteria study suggests that the HTL-pathway could be engineered as a superior alternative for sludge stabilization and resource recovery if phosphorus recovery and its technology readiness level could be improved.


Asunto(s)
Aguas del Alcantarillado , Aguas Residuales , Anaerobiosis , Aguas Residuales/química , Fósforo , Eliminación de Residuos Líquidos/métodos , Nitrógeno , Purificación del Agua/métodos
2.
Ultrasound Obstet Gynecol ; 63(3): 312-320, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37519216

RESUMEN

OBJECTIVES: To determine the incremental diagnostic yield of exome sequencing (ES) after negative chromosomal microarray analysis (CMA) in cases of prenatally diagnosed agenesis of the corpus callosum (ACC) and to identify the associated genes and variants. METHODS: A systematic search was performed to identify relevant studies published up until June 2022 using four databases: PubMed, SCOPUS, Web of Science and The Cochrane Library. Studies in English reporting on the diagnostic yield of ES following negative CMA in prenatally diagnosed partial or complete ACC were included. Authors of cohort studies were contacted for individual participant data and extended cohorts were provided for two of them. The increase in diagnostic yield with ES for pathogenic/likely pathogenic (P/LP) variants was assessed in all cases of ACC, isolated ACC, ACC with other cranial anomalies and ACC with extracranial anomalies. To identify all reported genetic variants, the systematic review included all ACC cases; however, for the meta-analysis, only studies with ≥ three ACC cases were included. Meta-analysis of proportions was employed using a random-effects model. Quality assessment of the included studies was performed using modified Standards for Reporting of Diagnostic Accuracy criteria. RESULTS: A total of 28 studies, encompassing 288 prenatally diagnosed ACC cases that underwent ES following negative CMA, met the inclusion criteria of the systematic review. We classified 116 genetic variants in 83 genes associated with prenatal ACC with a full phenotypic description. There were 15 studies, encompassing 268 cases, that reported on ≥ three ACC cases and were included in the meta-analysis. Of all the included cases, 43% had a P/LP variant on ES. The highest yield was for ACC with extracranial anomalies (55% (95% CI, 35-73%)), followed by ACC with other cranial anomalies (43% (95% CI, 30-57%)) and isolated ACC (32% (95% CI, 18-51%)). CONCLUSIONS: ES demonstrated an incremental diagnostic yield in cases of prenatally diagnosed ACC following negative CMA. While the greatest diagnostic yield was observed in ACC with extracranial anomalies and ACC with other central nervous system anomalies, ES should also be considered in cases of isolated ACC. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Agenesia del Cuerpo Calloso , Secuenciación del Exoma , Femenino , Humanos , Embarazo , Agenesia del Cuerpo Calloso/diagnóstico por imagen , Agenesia del Cuerpo Calloso/genética , Cuerpo Calloso
3.
J Plast Reconstr Aesthet Surg ; 89: 75-85, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38160590

RESUMEN

Breast augmentation is often performed as a day-case general anaesthetic operation, with postoperative, opioid-based analgesia regimens. However, it may also be performed using regional anaesthesia; a variety of nerve block techniques are available to reduce postoperative pain and analgesic requirements. This systematic review and meta-analysis were undertaken according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines comparing breast augmentation using regional anaesthesia with general anaesthesia, versus general anaesthesia alone or with local field infiltration. All randomised or quasi-randomised studies that recruited adult female patients undergoing breast augmentation using regional anaesthesia were considered. The primary outcome measures were postoperative pain and analgesic requirements. A randomised effects model was used, with standardised mean difference or mean difference outcomes used as appropriate. Thirteen studies were included for systematic review, out of which eight met the inclusion criteria for meta-analysis. Nerve blocks had statistically significant standardised mean difference reductions in postoperative pain scores across all time points: 0 h (-1.2 [-2.1 to -0.3], p = 0.01, I2 = 85%), 1 h (-1.3 [-2.1 to -0.5], p = 0.002, I2 = 89%), 2 h (-1.8 [-2.8 to -0.9], p = 0.0002, I2 = 88%), 4-6 h (-1.2 [-2.1 to -0.4], p = 0.006, I2 = 89%), 24 h (-1.4 [-2.5 to -0.2], p = 0.02, I2 = 94%). There was also a statistically significant reduction in postoperative opioid requirements: -150 mcg fentanyl (-259.2 to -40.9), p = 0.007. Although an element of study heterogeneity is noted, this systematic review and meta-analysis support the concept that regional anaesthesia using nerve blocks in breast augmentation surgery, reduces both postoperative pain and opioid requirements, compared with general anaesthesia.


Asunto(s)
Anestesia de Conducción , Mamoplastia , Bloqueo Nervioso , Adulto , Humanos , Femenino , Analgésicos Opioides/uso terapéutico , Bloqueo Nervioso/métodos , Dolor Postoperatorio/prevención & control
4.
Artículo en Inglés | MEDLINE | ID: mdl-37979977

RESUMEN

Lectins are predominantly oligomeric proteins with several binding sites per molecule. Glycoconjugates are their natural ligands, which often possess multiple binding epitopes. Thus, lectin-glycoconjugate interactions are mostly multivalent in nature. The mechanism of multivalent binding is fundamentally different from those described for monovalent interactions in textbooks and research papers. Over the years, binding studies that make use of different lectins and a variety of multivalent glycoconjugate ligands were conducted in order to understand the underlying principles of multivalency. Starting with seemingly simple synthetic multivalent analogs, systematic studies were carried out using natural glycoconjugate ligands with increasing valency and complexity. Those ligands included multivalent glycoproteins, polyvalent polysaccharides, including glycosaminoglycans, as well as supra-valent mucins and proteoglycans. Models and mechanisms of multivalent binding derived from quantitative data are summarized in the present updated review.


Asunto(s)
Glicoconjugados , Lectinas , Lectinas/química , Lectinas/metabolismo , Glicoconjugados/química , Glicoproteínas/química , Polisacáridos , Mucinas
5.
Adv Carbohydr Chem Biochem ; 84: 23-48, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37979978

RESUMEN

The biological signaling properties of lectins, which are carbohydrate-binding proteins, are due to their ability to bind and cross-link multivalent glycoprotein receptors on the surface of normal and transformed cells. While the cross-linking properties of lectins with multivalent carbohydrates and glycoproteins are relatively well understood, the mechanisms of binding of lectins to multivalent glycoconjugates are less well understood. Recently, the thermodynamics of binding of lectins to synthetic clustered glycosides, a multivalent globular glycoprotein, and to linear glycoproteins (mucins) have been described. The results are consistent with a dynamic binding mechanism in which lectins bind and jump from carbohydrate to carbohydrate epitope in these molecules. Importantly, the mechanism of binding of lectins to mucins is similar to that for a variety of protein ligands binding to DNA. Recent analysis also shows that high-affinity lectin-mucin cross-linking interactions are driven by favorable entropy of binding that is associated with the bind and jump mechanism. The results suggest that the binding of ligands to biopolymers, in general, may involve a common mechanism that involves enhanced entropic effects which facilitate binding and subsequent complex formation including enzymology.


Asunto(s)
Carbohidratos , Lectinas , Lectinas/química , Lectinas/metabolismo , Unión Proteica , Carbohidratos/química , Termodinámica , Mucinas/química , Mucinas/metabolismo
6.
J Environ Manage ; 347: 119075, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37769474

RESUMEN

This study evaluated two pathways to recover the nitrogen-content of wastewater sludges as ammonium sulfate (AmS) for use as fertilizer. The first pathway entails sludge stabilization by hydrothermal liquefaction (HTL) followed by recovery of AmS from the resulting aqueous product by gas permeable membrane (GPM) separation. The second one entails stabilization of the sludges by anaerobic digestion (AD) followed by recovery of AmS from the resulting centrate by GPM separation. A bench-scale GPM reactor is shown to be capable of recovering >90% of N in the feed. Recoveries of NH3-N in the HTL-pathway ranged 96-100% in 5.5-7.5 h at mass removal rates of 0.2-0.3 g N/day, yielding 3.3-6.0 g AmS/L of feed. Recoveries of 98% were noted in the AD-pathway in 4 h at mass removal rates of 0.06-0.97 g N/day and a yield of 1.7-2.1 g AmS/L of feed. Inductively coupled plasma optical emission spectrometer analysis confirmed that both pathways yielded AmS meeting the US EPA and European region guidelines for land application. The GPM reactor enabled higher nitrogen-recoveries in the HTL-pathway than those reported for current practice of AD followed by ammonia stripping, ion exchange, reverse osmosis, and/or struvite precipitation (96-100% vs. 50-90%). A process model for the GPM reactor is validated using performance data on three different feedstocks.


Asunto(s)
Aguas del Alcantarillado , Aguas Residuales , Anaerobiosis , Sulfato de Amonio , Estudios de Factibilidad , Nitrógeno , Reactores Biológicos
7.
World J Surg ; 46(12): 2910-2918, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36064868

RESUMEN

BACKGROUND: Pilonidal disease can be a debilitating condition which carries a significant physical and economic burden. This systematic review and updated meta-analysis presents the evidence for the use of platelet-rich plasma (PRP) for wound healing following open and minimally-invasive sacrococcygeal pilonidal surgery. METHODS: A literature search was performed during December 2021 for studies relating to platelet-rich plasma and pilonidal wound healing following surgery. RESULTS: Nine studies remained after applying the exclusion criteria, incorporating a total of 621 (open surgery group) and 309 (minimally-invasive group) patients, respectively. Pooled analysis of the six open surgery group studies demonstrated a significant reduction in wound healing time (mean difference [MD] = - 13.98 days, 95% CI - 18.41 to - 9.55, p < 0.001, I2 = 98%). Three open surgery group studies compared post-operative time off work, while three recorded mean pain duration; pooled analysis also revealed a significant reduction in both outcomes, respectively (MD = - 8.7 days, 95% CI - 9.4 to - 8.0, p < 0.001, I2 = 57%; MD = - 9.5 days, 95% CI - 15.6 to - 3.3, p = 0.002, I2 = 98%). Methodological heterogeneity among the minimally-invasive studies precluded formal meta-analysis; however, two studies demonstrated a modest improvement in wound healing when treated with PRP. CONCLUSIONS: This systematic review and updated meta-analysis provide further evidence supporting the use of PRP for wound healing in sacrococcygeal pilonidal disease. PRP application was demonstrated to significantly reduce healing time, postoperative pain and time off work in the open surgery group. Nevertheless, there is still considerable heterogeneity among PRP manufacture and administration techniques, and further high-powered RCTs with consistent methodology are required to substantiate these findings.


Asunto(s)
Seno Pilonidal , Plasma Rico en Plaquetas , Humanos , Seno Pilonidal/cirugía , Cicatrización de Heridas , Procedimientos Quirúrgicos Mínimamente Invasivos
8.
Ann Oncol ; 33(12): 1318-1327, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36122798

RESUMEN

BACKGROUND: Breast cancer has a significant heritable basis, of which ∼60% remains unexplained. Testing for BRCA1/BRCA2 offers useful discrimination of breast cancer risk within families, and identification of additional breast cancer susceptibility genes could offer clinical utility. PATIENTS AND METHODS: We included 2135 invasive breast cancer cases recruited via the Breast and Ovarian Cancer Susceptibility study, a retrospective UK study of familial breast cancer. ELIGIBILITY CRITERIA: female, BRCA-negative, white European ethnicity, and one of: (i) breast cancer family history, (ii) bilateral disease, (iii) young age of onset (<30 years), and (iv) concomitant ovarian cancer. We undertook exome sequencing of cases and carried out gene-level burden testing of rare damaging variants against those from 51 377 ethnicity-matched population controls from gnomAD. RESULTS: 159/2135 (7.4%) cases had a qualifying variant in an established breast cancer susceptibility gene, with minimal evidence of signal in other cancer susceptibility genes. Known breast cancer susceptibility genes PALB2, CHEK2, and ATM were the only genes to retain statistical significance after correcting for multiple testing. Due to the enrichment of hereditary cases in the series, we had good power (>80%) to detect a gene of BRCA1-like risk [odds ratio (OR) = 10.6] down to a population minor allele frequency of 4.6 × 10-5 (1 in 10 799, less than one-tenth that of BRCA1)and of PALB2-like risk (OR = 5.0) down to a population minor allele frequency of 2.8 × 10-4 (1 in 1779, less than half that of PALB2). Power was lower for identification of novel moderate penetrance genes (OR = 2-3) like CHEK2 and ATM. CONCLUSIONS: This is the largest case-control whole-exome analysis of enriched breast cancer published to date. Whilst additional breast cancer susceptibility genes likely exist, those of high penetrance are likely to be of very low mutational frequency. Contention exists regarding the clinical utility of such genes.


Asunto(s)
Neoplasias de la Mama , Neoplasias Ováricas , Neoplasias de la Mama Triple Negativas , Femenino , Humanos , Adulto , Mutación de Línea Germinal , Neoplasias de la Mama/genética , Neoplasias de la Mama/diagnóstico , Estudios Retrospectivos , Predisposición Genética a la Enfermedad , Neoplasias Ováricas/genética
9.
Methods Mol Biol ; 2442: 169-185, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35320526

RESUMEN

Isothermal titration microcalorimetry (ITC) can directly determine the thermodynamic binding parameters of biological molecules including affinity constant, binding stoichiometry, heat of binding (enthalpy) and indirectly the entropy, and free energy of binding. ITC has been extensively used to study the binding of lectins to mono- and oligosaccharides, but limitedly in applications to lectin-glycoprotein interactions. Inherent experimental challenges to ITC include sample precipitation during the experiment and relative high amount of sample required, but careful design of experiments can minimize these problems and allow valuable information to be obtained. For example, the thermodynamics of binding of lectins to multivalent globular and linear glycoproteins (mucins) have been described. The results are consistent with a dynamic binding mechanism in which lectins bind and jump from carbohydrate to carbohydrate epitope in these molecules leading to increased affinity. Importantly, the mechanism of binding of lectins to mucins appears similar to that for a variety of protein ligands binding to DNA. Recent results also show that high-affinity lectin-mucin cross-linking interactions are driven by favorable entropy of binding that is associated with the bind and jump mechanism. The results suggest that the binding of ligands to biopolymers, in general, may involve a common mechanism that involves enhanced entropic effects that facilitate binding interactions.


Asunto(s)
Lectinas , Mucinas , Calorimetría/métodos , Lectinas/metabolismo , Mucinas/metabolismo , Unión Proteica , Termodinámica
10.
Am J Hosp Palliat Care ; 39(12): 1377-1382, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35044876

RESUMEN

Experts in the field of palliative care in the United States (U.S.) have defined competence, or "good," mainly for programs, trainees, or providers of primary palliative care. Our interprofessional workgroup of palliative care specialists proposes that setting a standard for clinical excellence, or "great," applicable to palliative care specialists of all professions will elevate the field in the U.S. by providing an aspirational target usable for individual assessment and self-assessment, highlighting the common ground between team roles, and promoting a deeper understanding of teamwork, utilization, and productivity. We call for research that utilizes inclusive methods and broad representation of diverse voices to design a vivid, practical, and evidence-based definition of clinical excellence for palliative care specialists.


Asunto(s)
Enfermería de Cuidados Paliativos al Final de la Vida , Cuidados Paliativos , Humanos , Estados Unidos
11.
Ann R Coll Surg Engl ; 103(7): e231-e233, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34192489

RESUMEN

Chyle leak is a rare complication in colorectal surgery. It occurs due to disruption of the lymphatic drainage network in the abdomen or retroperitoneum. We describe the first reported case of chyle leak following total colectomy for inflammatory bowel disease. Our patient underwent total colectomy for severe ulcerative colitis not responsive to medical treatment. Four days postoperatively, a milky fluid was noted in the drainage bag. Analysis of the fluid confirmed chyle. The patient remained well and was successfully managed conservatively with a fat-free elemental diet and was discharged from hospital on day 12 postoperatively. A review of the literature suggests that conservative management with dietary modification is a common and effective management strategy; however, medical and surgical options exist for refractory cases.


Asunto(s)
Quilo , Colectomía/efectos adversos , Colitis Ulcerosa/cirugía , Dieta con Restricción de Grasas , Complicaciones Posoperatorias/diagnóstico , Adulto , Tratamiento Conservador/métodos , Drenaje , Femenino , Humanos , Complicaciones Posoperatorias/dietoterapia , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/patología , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
13.
Methods Mol Biol ; 1966: 137-149, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31041744

RESUMEN

Increases in levels of protoporphyrin IX (PPIX; a heme precursor) may be driven by xenobiotic induction of aminolevulinic acid synthase 1 (ALAS1) expression. ALAS1 is the rate-limiting enzyme of heme biosynthesis and may be upregulated to satisfy the increased need for heme in CYP450 enzymes. Therefore, a high-throughput fluorescence spectroscopy method that detects PPIX would enable the screening of drugs that increase ALAS1 through nuclear hormone receptor-mediated induction of transcription that may cause toxicity or even provide utility in the diagnosis or treatment of cancers that have elevated cellular PPIX levels. This chapter describes a high-throughput plate-based imaging technique for determining cellular protoporphyrin levels by using the GE Healthcare InCell 6000 confocal imaging system to detect the presence and location of PPIX in each cell and may be adapted for use with other imaging systems. Laser excitation and a scientific-grade complementary metal oxide semiconductor (CMOS) camera generate short exposure times, decreasing photobleaching in the target cells that may result in inaccurate measurements of PPIX and increasing screening throughput. Nuclear staining was detected by using a laser with 405-nm excitation and 455-nm emission wavelengths, and the presence of PPIX was measured using 405-nm excitation and 706-nm emission wavelengths. Image analysis involving top-hat segmentation on both nuclear and PPIX staining was performed by using the InCell Analyzer Workstation software. This assay may be adapted to screen for PPIX formation, degradation, and transportation effectors. Indeed, the inclusion of PPIX transport inhibition would be expected to further widen the linear range of fluorescence and improve the method.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento/métodos , Microscopía Confocal/métodos , Protoporfirinas/análisis , Espectrometría de Fluorescencia/métodos , Células Hep G2 , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Microscopía Fluorescente/métodos
14.
Acute Med ; 18(4): 251-254, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31912058

RESUMEN

Purple urine bag syndrome is a potentially alarming phenomenon caused by bacterial metabolism of urinary tryptophan into indigo (blue) and indirubin (red) pigments. We report the case of a 46-year-old female with an ileal conduit who presented with a 2 week history of abdominal pain and purple discolouration of her urine. In addition, we review the literature on purple urine bag syndrome, and identify potential new risk factors and management considerations.


Asunto(s)
Infecciones por Clostridium , Triptófano , Derivación Urinaria , Infecciones Urinarias , Orina , Infecciones por Clostridium/complicaciones , Infecciones por Clostridium/diagnóstico , Color , Femenino , Humanos , Persona de Mediana Edad , Síndrome , Triptófano/metabolismo , Cateterismo Urinario , Infecciones Urinarias/complicaciones , Infecciones Urinarias/diagnóstico
15.
Glycobiology ; 28(7): 437-442, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29618060

RESUMEN

The mucin-type O-glycome in cancer aberrantly expresses the truncated glycans Tn (GalNAcα1-Ser/Thr) and STn (Neu5Acα2,6GalNAcα1-Ser/Thr). However, the role of Tn and STn in cancer and other diseases is not well understood. Our recent discovery of the self-binding properties (carbohydrate-carbohydrate interactions, CCIs) of Tn (Tn-Tn) and STn (STn-STn) provides a model for their possible roles in cellular transformation. We also review evidence that Tn and STn are members of a larger family of glycan tumor antigens that possess CCIs, which may participate in oncogenesis.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Carcinogénesis , Polisacáridos/metabolismo , Animales , Antígenos de Neoplasias/química , Humanos , Polisacáridos/química
16.
Sci Rep ; 7: 46751, 2017 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-28436464

RESUMEN

Pregnane X receptor (PXR) is a xenobiotic receptor that regulates the detoxification and clearance of drugs and foreign compounds from the liver. There has been mounting evidence of crosstalk between the drug metabolism pathway and the energy metabolism pathway, but little is known about this cross-regulation. To further delineate the energy metabolism and drug metabolism crosstalk in this study, we exposed HepG2 cells to varying glucose concentrations. We observed that PXR activity was induced under high-glucose conditions. This finding is consistent with previous clinical reports of increased drug clearance in patients with untreated diabetes. We demonstrated that AMP-activated protein kinase (AMPK) modulates PXR transcriptional activity and that pharmacologically manipulated AMPK activation exhibits an inverse relation to PXR activity. Activation of AMPK was shown to downregulate PXR activity and, consistent with that, potentiate the response of cells to the drug. Taken together, our results delineate a hitherto unreported axis of regulation that involves the energy status of the cell, PXR regulation, and drug sensitivity.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Glucosa/farmacología , Receptor X de Pregnano/metabolismo , Células CACO-2 , Línea Celular Tumoral , Células Cultivadas , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Receptor X de Pregnano/genética
17.
Hum Reprod ; 31(12): 2756-2764, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27816925

RESUMEN

STUDY QUESTION: Does 'metformin' reduce the incidence of ovarian hyperstimulation syndrome (OHSS) for women with polycystic ovary syndrome (PCOS) undergoing a GnRH antagonist assisted conception treatment cycle? SUMMARY ANSWER: A short course of metformin does not reduce the incidence of OHSS for women with PCOS undergoing a GnRH antagonist treatment cycle. WHAT IS KNOWN ALREADY: Metformin does reduce the incidence of OHSS in a GnRH-agonist treatment cycle. STUDY DESIGN, SIZE, DURATION: A randomised placebo-controlled trial (RCT) using metformin or placebo. Randomisation was blinded to both patient and investigator, using a random permuted blocks method with a 50:50 allocation ratio. The study was completed over 5 years (2009-2014) with 153 randomised patients. A sample size calculation based on the incidence of OHSS was completed prospectively suggesting a minimum of 146 recruits was required for the trial with a power of 80% and a type 1 error of 0.05. PARTICIPANTS/MATERIALS, SETTING, METHODS: All patients met the Rotterdam criteria for PCOS and were treated with a standard GnRH antagonist IVF/ICSI treatment cycle in a tertiary infertility clinic. The study medication was started prior to stimulation and continued to oocyte retrieval. Of the 153 patients, 77 received metformin and 76 placebo. MAIN RESULTS AND THE ROLE OF CHANCE: There was no reduction in the incidence of moderate-severe OHSS (Placebo (PLA) 12.2%, metformin (MET) = 16%, 95% CI -0.08-0.16, P = 0.66). There was no difference in total gonadotrophin dose (PLA = 1200, MET = 1200, 95% CI -118.67-118.67, P = 0.75), oocytes retrieved (PLA = 15, MET = 14, 95% CI -2.37-4.37, P = 0.66) or fertilisation rate (PLA = 60.7%, MET = 53.3%, 95% CI -0.96-14.94, P = 0.07). However, using metformin resulted in a reduced clinical pregnancy rate (CPR) per cycle started (PLA = 48.7%, MET = 28.6%, 95% CI 0.04-0.35, P = 0.02) and live birth rate (PLA = 51.6%, MET = 27.6%, 95% CI 0.05-0.40, P = 0.02). Furthermore, when ethnicity was taken into account there was a significant reduction in pregnancy outcome for the South Asian population irrespective of metformin or placebo use (CPR per cycle started, White Caucasian = 44.4%, South Asian = 19.4%; 95% CI 0.06-0.39, P = 0.01). LIMITATIONS, REASONS FOR CAUTION: This study was only undertaken on an infertility population with PCOS with a limited duration of study medication use. WIDER IMPLICATIONS OF THE FINDINGS: This is the first adequately powered RCT to assess the impact of metformin on OHSS in a high-risk group (women with PCOS) undergoing a GnRH antagonist cycle. It does not support the empirical prescribing of metformin as an adjunct to a GnRH antagonist treatment cycle. STUDY FUNDING/COMPETING INTERESTS: None. TRIAL REGISTRATION NUMBER: EudraCT number 2009-010952-81. TRIAL REGISTRATION DATE: 21 September 2009. DATE OF FIRST PATIENT'S ENROLMENT: 30 October 2009.


Asunto(s)
Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Antagonistas de Hormonas/efectos adversos , Infertilidad Femenina/terapia , Metformina/uso terapéutico , Síndrome de Hiperestimulación Ovárica/prevención & control , Inducción de la Ovulación/métodos , Síndrome del Ovario Poliquístico/terapia , Adulto , Femenino , Hormona Liberadora de Gonadotropina/efectos adversos , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/uso terapéutico , Antagonistas de Hormonas/uso terapéutico , Humanos , Síndrome de Hiperestimulación Ovárica/inducido químicamente , Embarazo , Índice de Embarazo , Resultado del Tratamiento
18.
Acta Pharm Sin B ; 6(5): 441-449, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27709012

RESUMEN

The pregnane X receptor (PXR) plays an important and diverse role in mediating xenobiotic induction of drug-metabolizing enzymes and transporters. Several protein isoforms of PXR exist, and they have differential transcriptional activity upon target genes; transcript variants 3 (PXR3) and 4 (PXR4) do not induce target gene expression, whereas transcript variants 1 (PXR1) and 2 (PXR2) respond to agonist by activating target gene expression. PXR protein variants also display differences in protein-protein interactions; PXR1 interacts with p53, whereas PXR3 does not. Furthermore, the transcript variants of PXR that encode these protein isoforms are differentially regulated by methylation and deletions in the respective promoters of the variants, and their expression differs in various human cancers and also in cancerous tissue compared to adjacent normal tissues. PXR1 and PXR4 mRNA are downregulated by methylation in cancerous tissue and have divergent effects on cellular proliferation when ectopically overexpressed. Additional detailed and comparative mechanistic studies are required to predict the effect of PXR transcript variant expression on carcinogenesis, therapeutic response, and the development of toxicity.

19.
Am J Bioeth ; 16(10): 52-4, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27653402

Asunto(s)
Salud Global , Humanos
20.
Glycobiology ; 26(12): 1338-1350, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27282157

RESUMEN

The molecular mechanism(s) underlying the enhanced self-interactions of mucins possessing the Tn (GalNAcα1-Ser/Thr) or STn (NeuNAcα2-6GalNAcα1-Ser/Thr) cancer markers were investigated using optical tweezers (OT). The mucins examined included modified porcine submaxillary mucin containing the Tn epitope (Tn-PSM), ovine submaxillary mucin with the STn epitope (STn-OSM), and recombinant MUC1 analogs with either the Tn and STn epitope. OT experiments in which the mucins were immobilized onto polystyrene beads revealed identical self-interaction characteristics for all mucins. Identical binding strength and energy landscape characteristics were also observed for synthetic polymers displaying multiple GalNAc decorations. Polystyrene beads without immobilized mucins showed no self-interactions and also no interactions with mucin-decorated polystyrene beads. Taken together, the experimental data suggest that in these molecules, the GalNAc residue mediates interactions independent of the anchoring polymer backbone. Furthermore, GalNAc-GalNAc interactions appear to be responsible for self-interactions of mucins decorated with the STn epitope. Hence, Tn-MUC1 and STn-MUC1 undergo self-interactions mediated by the GalNAc residue in both epitopes, suggesting a possible molecular role in cancer. MUC1 possessing the T (Galß1-3GalNAcα1-Ser/Thr) or ST antigen (NeuNAcα2-3Galß1-3GalNAcα1-Ser/Thr) failed to show self-interactions. However, in the case of ST-MUC1, self-interactions were observed after subsequent treatment with neuraminidase and ß-galactosidase. This enzymatic treatment is expected to introduce Tn-epitopes and these observations thus further strengthen the conclusion that the observed interactions are mediated by the GalNAc groups.


Asunto(s)
Acetilgalactosamina/metabolismo , Antígenos de Carbohidratos Asociados a Tumores/metabolismo , Mucina-1/metabolismo , Mucinas/metabolismo , Animales , Bovinos , Humanos , Porcinos
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