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1.
Biochemistry ; 61(11): 1064-1076, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35584037

RESUMEN

G-Quadruplex (G4) structures play a pivotal role in diverse biological functions, including essential processes, such as telomere maintenance and gene regulation. G4 structures formed in functional regions of genomes are actively pursued toward therapeutics and are targeted by small-molecule ligands that alter their structure and/or stability. Herein, we report the synthesis of bisindolylmaleimide-based (BIM) ligands, which preferentially stabilize parallel G4 structures of c-MYC and c-KIT oncogenes over the telomeric h-RAS1 G4 and duplex DNAs. The preferential stabilization of parallel G4s with BIM ligands is further validated by the DNA polymerase stop assay, where stop products were only observed for templates containing the c-MYC G4 sequence. Nuclear magnetic resonance (NMR) titration studies indicate that the lead ligand BIM-Pr1 forms a 2:1 complex with c-MYC G4 DNA with a KD of 38 ± 5 µM. The BIM ligand stacks at the 5' and 3' quartets, with molecular modeling and dynamics studies supporting the proposed binding mode. The ligand is cytotoxic to HeLa cells and downregulates c-MYC gene expression. Collectively, the results present bisindolylmaleimide scaffolds as novel and powerful G4 targeting agents.


Asunto(s)
G-Cuádruplex , ADN/química , ADN/genética , Expresión Génica , Células HeLa , Humanos , Indoles , Ligandos , Maleimidas , Telómero
2.
Ann Oncol ; 27(4): 648-53, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26802153

RESUMEN

BACKGROUND: In the phase III MPACT trial, nab-paclitaxel plus gemcitabine (nab-P + Gem) demonstrated superior efficacy versus Gem alone for patients with metastatic pancreatic cancer. We sought to examine the feasibility of positron emission tomography (PET) and to compare metabolic response rates and associated correlations with efficacy in the MPACT trial. PATIENTS AND METHODS: Patients with previously untreated metastatic adenocarcinoma of the pancreas were randomized 1:1 to receive nab-P + Gem or Gem alone. Treatment continued until disease progression by RECIST or unacceptable toxicity. RESULTS: PET scans were carried out on the first 257 patients enrolled at PET-equipped centers (PET cohort). Most patients (252 of 257) had ≥2 PET-avid lesions, and median maximum standardized uptake values at baseline were 4.6 and 4.5 in the nab-P + Gem and Gem-alone arms, respectively. In a pooled treatment arm analysis, a metabolic response by PET (best response at any time during study) was associated with longer overall survival (OS) (median 11.3 versus 6.9 months; HR, 0.56; P < 0.001). Efficacy results within each treatment arm appeared better for patients with a metabolic response. The metabolic response rate (best response and week 8 response) was higher for nab-P + Gem (best response: 72% versus 53%, P = 0.002; week 8: 67% versus 51%; P = 0.014). Efficacy in the PET cohort was greater for nab-P + Gem versus Gem alone, including for OS (median 10.5 versus 8.4 months; hazard ratio [HR], 0.71; P = 0.009) and ORR by RECIST (31% versus 11%; P < 0.001). CONCLUSION: Pancreatic lesions were PET avid at baseline, and the rate of metabolic response was significantly higher for nab-P + Gem versus Gem alone at week 8 and for best response during study. Having a metabolic response was associated with longer survival, and more patients experienced a metabolic response than a RECIST-defined response. CLINICALTRIALSGOV: NCT00844649.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Albúminas/administración & dosificación , Desoxicitidina/análogos & derivados , Paclitaxel/administración & dosificación , Neoplasias Pancreáticas/tratamiento farmacológico , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Desoxicitidina/administración & dosificación , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Tomografía de Emisión de Positrones , Resultado del Tratamiento , Gemcitabina
3.
Ann Oncol ; 27(10): 1928-40, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27672108

RESUMEN

BACKGROUND: To evaluate the safety, tolerability, pharmacokinetics, and maximum tolerated dose (MTD) of copanlisib, a phosphatidylinositol 3-kinase inhibitor, in patients with advanced solid tumors or non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Phase I dose-escalation study including patients with advanced solid tumors or NHL, and a cohort of patients with type 2 diabetes mellitus. Patients received three weekly intravenous infusions of copanlisib per 28-day cycle over the dose range 0.1-1.2 mg/kg. Plasma copanlisib levels were analyzed for pharmacokinetics. Biomarker analysis included PIK3CA, KRAS, BRAF, and PTEN mutational status and PTEN immunohistochemistry. Whole-body [(18)F]-fluorodeoxyglucose positron emission tomography ((18)FDG-PET) was carried out at baseline and following the first dose to assess early pharmacodynamic effects. Plasma glucose and insulin levels were evaluated serially. RESULTS: Fifty-seven patients received treatment. The MTD was 0.8 mg/kg copanlisib. The most frequent treatment-related adverse events were nausea and transient hyperglycemia. Copanlisib exposure was dose-proportional with no accumulation; peak exposure positively correlated with transient hyperglycemia post-infusion. Sixteen of 20 patients treated at the MTD had reduced (18)FDG-PET uptake; 7 (33%) had a reduction >25%. One patient achieved a complete response (CR; endometrial carcinoma exhibiting both PIK3CA and PTEN mutations and complete PTEN loss) and two had a partial response (PR; both metastatic breast cancer). Among the nine NHL patients, all six with follicular lymphoma (FL) responded (one CR and five PRs) and one patient with diffuse large B-cell lymphoma had a PR by investigator assessment; two patients with FL who achieved CR (per post hoc independent radiologic review) were on treatment >3 years. CONCLUSION: Copanlisib, dosed intermittently on days 1, 8, and 15 of a 28-day cycle, was well tolerated and the MTD was determined to be 0.8 mg/kg. Copanlisib exhibited dose-proportional pharmacokinetics and promising anti-tumor activity, particularly in patients with NHL. CLINICALTRIALSGOV: NCT00962611; https://clinicaltrials.gov/ct2/show/NCT00962611.


Asunto(s)
Fosfatidilinositol 3-Quinasa Clase I/antagonistas & inhibidores , Inhibidores Enzimáticos/administración & dosificación , Linfoma no Hodgkin/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Pirimidinas/administración & dosificación , Quinazolinas/administración & dosificación , Administración Intravenosa , Adulto , Anciano , Fosfatidilinositol 3-Quinasa Clase I/genética , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/farmacocinética , Femenino , Humanos , Linfoma no Hodgkin/enzimología , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias/enzimología , Neoplasias/patología , Pirimidinas/efectos adversos , Pirimidinas/farmacocinética , Quinazolinas/efectos adversos , Quinazolinas/farmacocinética
4.
Ann Oncol ; 27(4): 654-60, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26802160

RESUMEN

BACKGROUND: A phase I/II study and subsequent phase III study (MPACT) reported significant correlations between CA19-9 decreases and prolonged overall survival (OS) with nab-paclitaxel plus gemcitabine (nab-P + Gem) treatment for metastatic pancreatic cancer (MPC). CA19-9 changes at week 8 and potential associations with efficacy were investigated as part of an exploratory analysis in the MPACT trial. PATIENTS AND METHODS: Untreated patients with MPC (N = 861) received nab-P + Gem or Gem alone. CA19-9 was evaluated at baseline and every 8 weeks. RESULTS: Patients with baseline and week-8 CA19-9 measurements were analyzed (nab-P + Gem: 252; Gem: 202). In an analysis pooling the treatments, patients with any CA19-9 decline (80%) versus those without (20%) had improved OS (median 11.1 versus 8.0 months; P = 0.005). In the nab-P + Gem arm, patients with (n = 206) versus without (n = 46) any CA19-9 decrease at week 8 had a confirmed overall response rate (ORR) of 40% versus 13%, and a median OS of 13.2 versus 8.3 months (P = 0.001), respectively. In the Gem-alone arm, patients with (n = 159) versus without (n = 43) CA19-9 decrease at week 8 had a confirmed ORR of 15% versus 5%, and a median OS of 9.4 versus 7.1 months (P = 0.404), respectively. In the nab-P + Gem and Gem-alone arms, by week 8, 16% (40/252) and 6% (13/202) of patients, respectively, had an unconfirmed radiologic response (median OS 13.7 and 14.7 months, respectively), and 79% and 84% of patients, respectively, had stable disease (SD) (median OS 11.1 and 9 months, respectively). Patients with SD and any CA19-9 decrease (158/199 and 133/170) had a median OS of 13.2 and 9.4 months, respectively. CONCLUSION: This analysis demonstrated that, in patients with MPC, any CA19-9 decrease at week 8 can be an early marker for chemotherapy efficacy, including in those patients with SD. CA19-9 decrease identified more patients with survival benefit than radiologic response by week 8.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Albúminas/administración & dosificación , Antígeno CA-19-9/sangre , Desoxicitidina/análogos & derivados , Paclitaxel/administración & dosificación , Neoplasias Pancreáticas/tratamiento farmacológico , Adenocarcinoma/sangre , Adenocarcinoma/patología , Adulto , Anciano , Biomarcadores Farmacológicos/sangre , Desoxicitidina/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/patología , Resultado del Tratamiento , Gemcitabina
5.
Climacteric ; 19(1): 71-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26555182

RESUMEN

OBJECTIVE: Menopausal symptoms are associated with a negative impact on the quality of life, leading women to seek medical treatment. Obesity has been linked to higher levels of menopausal symptoms such as hot flushes. This assessment will explore whether the prevalence and bother of hot flushes and vaginal dryness change from pre- to post-bariatric surgery among obese midlife women. METHODS: This study is a longitudinal analysis of data from 69 women (ages 35-72 years) undergoing bariatric surgery with reported reproductive histories and menopausal symptoms at preoperative and 6-month postoperative visits. Prevalence of and degree of bother of hot flushes and vaginal dryness at pre- and post-surgery were compared using McNemar's test and Wilcoxon signed-rank test. RESULTS: The reported degree of bother of symptoms associated with hot flushes decreased from pre- to post-surgery (p < 0.01). There was no significant change in the prevalence of hot flushes or vaginal dryness in the overall study sample. CONCLUSIONS: The degree of bother of symptoms associated with hot flushes among midlife women may decrease after bariatric surgery. These results highlight important secondary gains, including less bothersome menopausal symptoms, for women who choose bariatric surgery for weight loss.


Asunto(s)
Cirugía Bariátrica , Sofocos/epidemiología , Menopausia/fisiología , Obesidad/cirugía , Enfermedades Vaginales/epidemiología , Adulto , Anciano , Índice de Masa Corporal , Femenino , Humanos , Modelos Logísticos , Estudios Longitudinales , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Encuestas y Cuestionarios
6.
Poult Sci ; 94(2): 296-301, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25609690

RESUMEN

The objective was to determine the effects of oral lithium chloride supplementation on bone strength and mass in broiler chickens. Ninety-six broilers were assigned to 1 of 2 treatment groups (lithium chloride or control; n=48/treatment). Beginning at 1 or 3 wk of age, chickens were administered lithium chloride (20 mg/kg body weight) or water daily by oral gavage. At 6 wk of age, chickens were euthanized and bone and muscle samples were collected. A 24 h lithium chloride (20 mg/kg body weight) challenge determined that serum lithium chloride increased within 2 h and cleared the system within 24 h, demonstrating the effective delivery of lithium chloride. Treatment did not influence body weight (P≥0.20) or feed intake (P≥0.81), demonstrating that lithium chloride did not negatively affect broiler growth. To determine bone strength, 3-point bending was performed on the femora and tibiae obtained from control and lithium chloride-treated birds in the 1 wk group. Lithium chloride-treated birds had a 22% reduction in stiffness compared with control in the femora (P=0.02) without a corresponding reduction in elastic modulus. No differences were observed in yield or ultimate load and in the corresponding calculations of stresses (P≥0.26). The toughness of tibiae was not altered in lithium chloride compared with control (P=0.11). Bone length and micro-CT imaging were performed on the tibiae of control and lithium chloride groups. No differences (P≥0.52) in bone length, cortical or trabecular bone volume, trabecular thickness, number, or spacing were observed. Lithium chloride treatment did not affect pectoralis muscle color or lipid oxidation (P>0.05). In conclusion, lithium chloride treatment in broilers did not negatively affect growth or meat quality. A reduction in bone stiffness of the femur with lithium chloride treatment was observed, however unlike the mouse model, the dosages of lithium chloride used in the current study did not result in anabolic effects on broiler long bones.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Desarrollo Óseo/efectos de los fármacos , Pollos/crecimiento & desarrollo , Cloruro de Litio/farmacología , Animales , Fenómenos Biomecánicos , Esquema de Medicación , Peroxidación de Lípido , Cloruro de Litio/administración & dosificación , Masculino
7.
Br J Cancer ; 111(2): 272-80, 2014 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-24901237

RESUMEN

BACKGROUND: Ficlatuzumab, a humanised hepatocyte growth factor (HGF) IgG1κ inhibitory monoclonal antibody, was evaluated for recommended phase II dose (RP2D), safety, pharmacokinetics (PKs), antidrug antibody (ADA), pharmacodynamics (PDs) and antitumour activity as monotherapy or combined with erlotinib. METHODS: Patients with solid tumours received ficlatuzumab 2, 5, 10 or 20 mg kg(-1) intravenously every 2 weeks (q2w). Additional patients were treated at the RP2D erlotinib. RESULTS: Forty-one patients enrolled at doses ⩽20 mg kg(-1). Common adverse events (AEs) included peripheral oedema, fatigue and nausea. Three patients experienced grade ⩾3 treatment-related hyperkalaemia/hypokalaemia, diarrhoea or fatigue. Best overall response (44%) was stable disease (SD); median duration was 5.5 months (0.4-18.7 months). One patient has been on therapy with SD for >4 years. Pharmacokinetics of ficlatuzumab showed low clearance (0.17-0.26 ml h(-1) kg(-1)), a half-life of 6.8-9.4 days and dose-proportional exposure. Ficlatuzumab/erlotinib had no impact on the PK of either agent. No ADAs were detected. Ficlatuzumab increased serum HGF levels. CONCLUSIONS: Recommended phase II dose is 20 mg kg(-1) q2w for ficlatuzumab monotherapy or with erlotinib. Preliminary antitumour activity and manageable AEs were observed. Pharmacokinetics were dose-proportional and consistent with other IgG therapeutics. Ficlatuzumab was not immunogenic, and serum HGF was a potential PD marker.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Estudios de Cohortes , Clorhidrato de Erlotinib , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Neoplasias/metabolismo , Neoplasias/patología , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacocinética , Quinazolinas/administración & dosificación , Quinazolinas/efectos adversos , Quinazolinas/farmacocinética
8.
Ann Oncol ; 25(6): 1172-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24608198

RESUMEN

BACKGROUND: Oxaliplatin is an integral component of colorectal cancer treatment, but its use is limited by neurotoxicity. The Combined Oxaliplatin Neurotoxicity Prevention Trial (CONcePT) tested intermittent oxaliplatin (IO) administration and the use of concurrent calcium and magnesium salts (Ca/Mg), two modifications intended to reduce neurotoxicity and extend the duration of treatment. PATIENTS AND METHODS: In this trial involving double randomization, 140 patients were randomized to receive modified FOLFOX7 plus bevacizumab with IO (eight-cycle blocks of oxaliplatin treatment) versus continuous oxaliplatin (CO); and Ca/Mg versus placebo (pre- and postoxaliplatin infusion). The primary end point was time-to-treatment failure (TTF). RESULTS: One hundred thirty-nine patients were entered and treated up to the point of early study termination due to concerns by the data-monitoring committee (DMC) that Ca/Mg adversely affected tumor response. Tumor response was not a study end point. Given DMC concerns, an additional independent, blinded radiology review of all images showed no adverse effect of treatment schedule or Ca/Mg on response by Response Evaluation Criteria In Solid Tumors. The IO schedule was superior to CO [hazard ratio (HR) = 0.581, P = 0.0026] for both TTF and time-to-tumor progression (TTP) (HR = 0.533, P = 0.047). CONCLUSIONS: An IO dosing schedule had a significant benefit on both TTF and TTP versus CO dosing in this trial despite the very attenuated sample. There was no effect of Ca/Mg on response.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Gluconato de Calcio/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Sulfato de Magnesio/administración & dosificación , Compuestos Organoplatinos/administración & dosificación , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bevacizumab , Neoplasias Colorrectales/mortalidad , Método Doble Ciego , Femenino , Fluorouracilo , Humanos , Estimación de Kaplan-Meier , Leucovorina , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/efectos adversos , Oxaliplatino , Modelos de Riesgos Proporcionales
9.
Med J Malaysia ; 69(5): 216-8, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25638234

RESUMEN

OBJECTIVE: The aim is to find rate of return to work of surgically treated thoracolumbar fracture patients and to know if back pain, compensation issues or neurological status influence this rate. METHODOLOGY: A retrospective cohort study analysing the patients with thoracolumbar fractures treated surgically from January 2008 till December 2009. RESULTS: Neurological status is the main factor deciding return to work in this group. Back pain and compensation related issues were not statistically significant in influencing return to work. 74% of patients in this group return to work. CONCLUSION: Return to work among the patients with thoracolumbar fracture, treated surgically, is mainly dependent on neurological status and not the compensation related issues or back pain.

10.
Invest New Drugs ; 30(3): 1175-83, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21424698

RESUMEN

PURPOSE: Patients with metastatic pancreatic cancer have limited therapeutic options. The role of the Ras-Raf-MAPK pathway and of vascular endothelial growth factor in pancreatic carcinogenesis provided the rational to evaluate the efficacy of sorafenib with or without gemcitabine in a randomized phase II study. METHODS: Patients with metastatic pancreatic cancer were randomized to sorafenib alone (arm A) or sorafenib with gemcitabine (arm B). RESULTS: Arm A was closed to accrual at interim analysis due to the lack of objective response. Median PFS and OS were 2.3 and 4.3 months respectively. There was one partial response among the 37 patients in arm B. Median PFS and OS were 2.9 and 6.5 months respectively. There were more grade 3 and 4 toxicities in arm B with the most common being neutropenia (17%), thrombocytopenia (8%), alkaline phosphatase elevation (14%), venous thromboembolism (8%), diarrhea, hypokalemia and ALT elevation (5%) each. Several associations were noted between single nucleotide polymorphisms in ribonucleotide reductase, Cox-2, vascular endothelial growth factor and survival in patients treated with gemcitabine and sorafenib. CONCLUSIONS: Neither sorafenib alone or sorafenib in combination with gemcitabine manifested promising activity in metastatic pancreatic cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclooxigenasa 2/genética , Nucleósido Desaminasas/genética , Neoplasias Pancreáticas/tratamiento farmacológico , Proteínas Supresoras de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bencenosulfonatos/administración & dosificación , Bencenosulfonatos/efectos adversos , Citidina Desaminasa , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Niacinamida/análogos & derivados , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Compuestos de Fenilurea , Polimorfismo de Nucleótido Simple , Piridinas/administración & dosificación , Piridinas/efectos adversos , Ribonucleósido Difosfato Reductasa , Sorafenib , Gemcitabina
11.
Phys Rev Lett ; 109(2): 020404, 2012 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-23030134

RESUMEN

We study the contextuality of a three-level quantum system using classical conditional entropy of measurement outcomes. First, we analytically construct the minimal configuration of measurements required to reveal contextuality. Next, an entropic contextual inequality is formulated, analogous to the entropic Bell inequalities derived by Braunstein and Caves [Phys. Rev. Lett. 61, 662 (1988)], that must be satisfied by all noncontextual theories. We find optimal measurements for violation of this inequality. The approach is easily extendable to higher dimensional quantum systems and more measurements. Our theoretical findings can be verified in the laboratory with current technology.

13.
Phys Rev Lett ; 106(18): 180402, 2011 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-21635070

RESUMEN

We present a method to derive Bell monogamy relations by connecting the complementarity principle with quantum nonlocality. The resulting monogamy relations are stronger than those obtained from the no-signaling principle alone. In many cases, they yield tight quantum bounds on the amount of violation of single and multiple qubit correlation Bell inequalities. In contrast with the two-qubit case, a rich structure of possible violation patterns is shown to exist in the multipartite scenario.

14.
Phys Rev Lett ; 107(6): 060405, 2011 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-21902303

RESUMEN

We identify conditions under which correlations resulting from quantum measurements performed on macroscopic systems (systems composed of a number of particles of the order of the Avogadro number) can be described by local realism. We argue that the emergence of local realism at the macroscopic level is caused by an interplay between the monogamous nature of quantum correlations and the fact that macroscopic measurements do not reveal properties of individual particles.

15.
IEEE/ACM Trans Comput Biol Bioinform ; 18(3): 1217-1226, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-31443044

RESUMEN

Feedback loops regulate various biological functions such as oscillations, bistability, and robustness. They play a significant role in developmental signalling and failure of feedback can lead to disease. Systematic analysis of feedback loops could be useful in understanding their properties and biological effects. We propose here a method to automatically analyze feedback loops in bio-pathways and synthesize temporal logic properties which describe their dynamics. Starting with an ordinary differential equations (ODEs) based model of a bio-pathway, for a chosen feedback loop present in the pathway, we use a convolutional neural network to classify the behaviours of the key components of the feedback according to templates specified in bounded linear temporal logic (BLTL). Once a template has been identified, we instantiate the symbolic variables appearing in the template and synthesize properties using a parameter estimation procedure based on sequential hypothesis testing. We have applied this framework to a number of bio-pathway models and validated that the synthesized properties faithfully describe the behaviours of the feedback loops.


Asunto(s)
Biología Computacional/métodos , Retroalimentación Fisiológica/fisiología , Modelos Biológicos , Modelos Estadísticos , Algoritmos
16.
Lung India ; 38(2): 168-173, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33687012

RESUMEN

Inhalation therapy is the cornerstone of chronic obstructive pulmonary disease (COPD) management. However, for many COPD patients who are managed at home, nebulization therapy offers an effective alternative treatment and fulfills the gap of catering to the specific population of patients who are unable to use handheld inhaler devices appropriately. The present review highlights key aspects, namely selection of the right beneficiaries for home nebulization, available drugs in nebulized formulations for the treatment of COPD, and the importance of care, cleaning, and maintenance, which are prerequisites for ensuring successful nebulization therapy.

17.
Ann Oncol ; 21(4): 754-758, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19887466

RESUMEN

BACKGROUND: The purpose of this study was to determine whether the presence of diabetes mellitus (DM) influences the incidence, severity, and/or course of peripheral sensory neuropathy (PSN) after oxaliplatin (FOLFOX) therapy in patients with colorectal cancer (CRC). METHODS: A retrospective pooled analysis incorporating three phase III studies was conducted: Multicenter International Study of Oxaliplatin, 5-Fluorouracil, and Leucovorin in the Adjuvant Treatment of Colon Cancer (MOSAIC) (adjuvant treatment; stage II/III colon cancer), EFC4584 (second-line treatment; metastatic CRC), and EFC2962 (first-line treatment; metastatic CRC). Patients were ineligible for the studies if they had known PSN (EFC4584) or PSN grade > or =1 (MOSAIC and EFC2962) at baseline. The incidence of PSN was evaluated retrospectively in patient subgroups with or without DM at baseline that received FOLFOX. Kaplan-Meier curves were used to assess the probability of PSN with increasing cumulative oxaliplatin dose. RESULTS: Of 1587 patients enrolled across the three studies, 135 (8.5%) had DM at baseline. The incidence of PSN (non-DM/DM) was 45.0%/46.7% (grade 1), 28.6%/26.7% (grade 2), and 13.0%/12.6% (grade 3). The probability of PSN by cumulative dose of oxaliplatin was similar in DM and non-DM patients. CONCLUSIONS: This retrospective analysis indicates that oxaliplatin-based therapy does not influence the incidence, severity, or time to onset of PSN in asymptomatic DM patients with CRC who meet eligibility criteria for clinical trials.


Asunto(s)
Carcinoma/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Complicaciones de la Diabetes/tratamiento farmacológico , Neuropatías Diabéticas/inducido químicamente , Neuropatías Diabéticas/epidemiología , Compuestos Organoplatinos/efectos adversos , Compuestos Organoplatinos/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Carcinoma/complicaciones , Carcinoma/patología , Ensayos Clínicos Fase III como Asunto/estadística & datos numéricos , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/patología , Complicaciones de la Diabetes/inducido químicamente , Complicaciones de la Diabetes/patología , Neuropatías Diabéticas/patología , Progresión de la Enfermedad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Oxaliplatino , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Estudios Retrospectivos , Células Receptoras Sensoriales/patología
18.
Adv Neonatal Care ; 10(5 Suppl): S15-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20838079

RESUMEN

Hypothermia remains a significant challenge in the initial care of premature infants. Although a number of prevention strategies have been identified, hypothermia is still a common event, especially in extremely low birth weight infants. Using data from four centers, we documented an incidence of hypothermia on admission to the neonatal intensive care unit from the delivery room of 31-78% for infants < 1500 g birth weight. Increased efforts will be necessary to prevent early hypothermia in very preterm infants, especially with respect to the environmental conditions of the delivery room itself. Journal of Perinatology (2007) 27, S45-S47. doi:10.1038/sj.jp.7211842.

19.
Physiother Res Int ; 25(1): e1809, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31502387

RESUMEN

BACKGROUND: Spastic cerebral palsy (CP) is the most common type of CP. Hip adductor spasticity leads to discomfort, stiffness, and difficulties in doing physical activities such as sitting, transfer, and walking. Management of hip adductor spasticity is still a challenge in the field of rehabilitation. Horse riding simulator (HRS) has been reported to have beneficial effects on spasticity, postural control, and motor function in children with spastic CP. OBJECTIVE: The aim of the study was to determine the immediate effect of HRS on adductor spasticity in children with CP. METHODS: Twenty-four children with CP were selected and were divided into two groups: experimental and control (12 children in each group). Experimental group was exposed to HRS and control group to the corner seat placement. Adductor tone and passive hip abduction range of motion were measured before and after the intervention. RESULTS: Post intervention scores in the group of HRS show significant reduction in adductor spasticity and improvement in hip abduction range of motion, whereas no difference have been reported in the control group. HRS has positive effects on reducing spasticity and improving range of motion in hip joint in spastic CP. CONCLUSION: It was concluded that immediate effect of HRS is successful in reducing the adductor spasticity and improving abduction range of motion in hip, which could be incorporated with regular physiotherapy intervention.


Asunto(s)
Parálisis Cerebral/rehabilitación , Terapía Asistida por Caballos/métodos , Espasticidad Muscular/rehabilitación , Rango del Movimiento Articular , Parálisis Cerebral/complicaciones , Niño , Preescolar , Terapía Asistida por Caballos/instrumentación , Femenino , Articulación de la Cadera/fisiopatología , Humanos , Masculino , Espasticidad Muscular/etiología , Espasticidad Muscular/fisiopatología , Modalidades de Fisioterapia , Equilibrio Postural , Caminata
20.
J Cell Biol ; 97(5 Pt 1): 1412-20, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6415066

RESUMEN

The excitable ciliary membrane of Paramecium regulates the direction of the ciliary beat, and thereby the swimming behavior of this organism. One approach to the problem of identifying the molecular components of the excitable membrane is to use antibodies as probes of function. We produced rabbit antisera against isolated ciliary membranes and against partially purified immobilization antigens derived from three serotypes (A, B, and H), and used these antisera as reagents to explore the role of specific membrane proteins in the immobilization reaction and in behavior. The immobilization characteristics and serotype cross-reactivities of the antisera were examined. We identified the antigens recognized by these sera using immunodiffusion and immunoprecipitation with 35S-labeled ciliary membranes. The major antigen recognized in homologous combinations of antigen-antiserum is the immobilization antigen (i-antigen), approximately 250,000 mol wt. Several secondary antigens, including a family of polypeptides of 42,000-45,000 mol wt, are common to the membranes of serotypes A, B, and H, and antibodies against these secondary antigens can apparently immobilize cells. This characterization of antiserum specificity has provided the basis for our studies on the effects of the antibodies on electrophysiological properties of cells and electron microscopic localization studies, which are reported in the accompanying paper. We have also used these antibodies to study the mechanism of cell immobilization by antibodies against the i-antigen. Monovalent fragments (Fab) against purified i-antigens bound to, but did not immobilize, living cells. Subsequent addition of goat anti-Fab antibodies caused immediate immobilization, presumably by cross-linking Fab fragments already bound to the surface. We conclude that antigen-antibody interaction per se is not sufficient for immobilization, and that antibody bivalency, which allows antigen cross-linking, is essential.


Asunto(s)
Anticuerpos/inmunología , Cilios/inmunología , Proteínas de la Membrana/inmunología , Paramecium/fisiología , Animales , Especificidad de Anticuerpos , Reacciones Cruzadas , Inmunodifusión , Fragmentos Fab de Inmunoglobulinas/inmunología , Movimiento
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