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1.
Artículo en Inglés | MEDLINE | ID: mdl-35854169

RESUMEN

The United States (U.S.) Department of Health and Human Services is interested in increasing geographical equity in access to liver transplant. The geographical disparity in the U.S. is fundamentally an outcome of variation in the organ supply to patient demand (s/d) ratios across the country (which cannot be treated as a single unit due to its size). To design a fairer system, we develop a nonlinear integer programming model that allocates the organ supply in order to maximize the minimum s/d ratios across all transplant centers. We design circular donation regions that are able to address the issues raised in legal challenges to earlier organ distribution frameworks. This allows us to reformulate our model as a set-partitioning problem. Our policy can be viewed as a heterogeneous donor circle policy, where the integer program optimizes the radius of the circle around each donation location. Compared to the current policy, which has fixed radius circles around donation locations, the heterogeneous donor circle policy greatly improves both the worst s/d ratio and the range between the maximum and minimum s/d ratios. We found that with the fixed radius policy of 500 nautical miles (NM), the s/d ratio ranges from 0.37 to 0.84 at transplant centers, while with the heterogeneous circle policy capped at a maximum radius of 500 NM, the s/d ratio ranges from 0.55 to 0.60, closely matching the national s/d ratio average of 0.5983. Our model matches the supply and demand in a more equitable fashion than existing policies and has a significant potential to improve the liver transplantation landscape.

2.
J Stroke Cerebrovasc Dis ; 29(12): 105378, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33080562

RESUMEN

OBJECTIVES: There is a little available information about the fatigue status among people receiving modified constraint induced movement therapy. The study examined such changes. The effect of using restraint on motor performance was also evaluated in sub acute phase after stroke. MATERIALS AND METHODS: The study was designed as two group pretest and post-test study. The experimental design included a pretest and post test measures of dependent variables fatigue and motor function. All patients were recruited from the Safdurjung Hospital. 20 patients in subacute phase of stroke (3-9 months), (N = 10) mean age±SD 51.90±15.27, MAS score mean ± SD 1.90±.316 and post stroke duration mean ±SD 6.45±2.26 were included in the experimental group and (N = 10) mean age ± SD 54.10±17.42, MAS score mean ±SD 1.52±0.52 and post stroke duration mean±SD score 4.55± 2.52 were included in the control group. The subjects in the experimental group were restrained for six hours every week day with task training for 2 h per day five times a week for three weeks and the subjects in the controlled group received task training for 2 h per day five times a week for three weeks with no restrain. Motor Performance and fatigue were measured on day to day basis by Wolf Motor Function Test Scores (WMFT) and 11th item of Barrow Neurological Institute (BNI) scale in both experimental and controlled group. RESULTS: The restraint group exhibited significant better motor performance than the controlled group. Mean difference between Pre- WMFT scores and Post WMFT scores were (0.533±.362) as compared to controlled group (0.192±.23). No significant statistical difference was observed in the difference of mean Pre- BNI and Post - BNI scores in either of the two groups (p = .57). Difference between the experimental and controlled group in motor performance and fatigue scores were nonsignificant. CONCLUSIONS: Restraint improves motor performance in subacute therapy group and the intensive practice associated with m-CIMT may be administered without the exacerbation of fatigue.


Asunto(s)
Técnicas de Ejercicio con Movimientos , Tolerancia al Ejercicio , Fatiga/fisiopatología , Actividad Motora , Fatiga Muscular , Restricción Física , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/terapia , Extremidad Superior/inervación , Adulto , Anciano , Fatiga/diagnóstico , Fatiga/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuperación de la Función , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo , Resultado del Tratamiento
3.
Indian J Public Health ; 64(4): 362-367, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33318386

RESUMEN

BACKGROUND: Combustion of kerosene and biomass fuel in the kitchen as cooking medium is one of the major sources of indoor air pollution. Such contaminated indoor air quality adversely affects the respiratory health of exposed individuals over a period of time. Homemaker women especially residing in slum areas are always vulnerable to indoor air-pollution-related health hazards. OBJECTIVES: The objective is to assess the relationship between various socio-demographic factors and usage patterns of cooking fuel; and to determine the effect of cooking medium namely biomass, kerosene on pulmonary function parameters. METHODS: A cross-sectional observational study was carried out during April 2012 - April 2016 among 531 nontobacco addicted adult primary homemaker women residing in slums of Ahmedabad city of Gujarat. Basic information-related socio-demographic parameters were collected on a pretested questionnaire. Pulmonary function test (PFT) parameters were evaluated with standard techniques. The statistical analysis was carried out with SPSS software (version 17.0). Statistical tests of significance between groups and mean along with multivariate linear regression analysis were applied. RESULTS: Predominant cooking medium for nearly 40% of slum households were kerosene and biomass. Mean value of forced expiratory volume in the 1st s (FEV1) and FEV1/forced vital capacity (FVC) were significantly lower among Kerosene and biomass users compared to LPG users. Multivariate regression analysis with involvement of PFT parameters, cooking medium, and environmental tobacco smoke exposure (ETS) shows, deprivation of both FEV1 and FEV1/FVC were significantly related with the usage of kerosene and biomass; whereas no relation found with ETS. CONCLUSION: Reduction of pulmonary function parameters among the study participants were related with kerosene and biomass fuel usage in the kitchen.


Asunto(s)
Queroseno , Áreas de Pobreza , Adulto , Biomasa , Culinaria , Estudios Transversales , Femenino , Humanos , India/epidemiología
4.
Protein Expr Purif ; 156: 1-7, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30562573

RESUMEN

Protein engineering is an emerging field for developing novel therapeutic proteins and commercial enzymes, along with a major impact on the global market. In recent decades, advanced methods employing protein modification through expansion of the genetic code have led to the development of proteins with new biochemical and physical properties. These techniques have produced engineered proteins with improved attribute comprising substrate relaxation, protein drug conjugation and high stability under extreme conditions of high temperatures, pH and organic solvents. Furthermore, residue specific incorporation is the simplest method for the global incorporation of non-canonical amino acid (NCAA) for protein modification; however it has the major drawbacks of high production cost and manpower requirement. In the present study, we developed a method for the incorporation of single NCAA in two different proteins by using Escherichia coli (E. coli) expression system. For that, the dual protein expressing Escherichia coli JW2581 strain was constructed by transforming pQE80L and pD881-PpiBT vectors with different promoters, selectable markers and AnnexinV, GFPHS gene. To modify the protein, the 3,4 dihydroxy phenyl alanine (DOPA) was globally incorporated into the GFPHS and Annexin V protein using dual protein expression system. The incorporation efficiency during the dual protein expression was achieved through optimized concentrations of amino acids, carbohydrate and inducers in minimal medium. This method for the incorporation of single NCAA into two different proteins using a single expression host system saves the production cost, manpower and time substantially.


Asunto(s)
Ingeniería de Proteínas/métodos , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes , Escherichia coli , Expresión Génica , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
5.
J Obstet Gynaecol ; 38(3): 305-309, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28974124

RESUMEN

Optimum dose, route and duration of use of prophylactic magnesium sulphate in women with severe pre-eclampsia is still controversial. We compared the efficacy and safety of 'low-dose Dhaka' regime with 'Loading dose only' regime for seizure prophylaxis in severe preeclampsia using a randomised controlled trial in 402 women. The incidence of eclampsia in the 'low-dose Dhaka' regime group was 1.49% and that in the 'Loading dose only regime' was 2.98% (p = .321). In the low-dose Dhaka regime, injection site abscess and respiratory depression occurred in one woman each. Neonatal outcomes such as Apgar score at 5 minutes (5.0% vs. 8.05% p = .251) and perinatal mortality (20.4% vs. 21.9%, p = .724) were similar in both groups. Loading dose only regime may be considered an effective alternative regime for the prevention of eclampsia in women with severe preeclampsia. Impact statement What is already known on this subject: Efficacy of therapeutic short regime magnesium sulphate in eclampsia has already been reported. Data regarding prophylactic short regime in women with preeclampsia is sparse. What the results of this study add: We have shown that short regime of magnesium sulphate using only the loading dose in the prevention of seizure in preeclampsia is an effective alternative to the low-dose Dhaka regime. What the implications are of these findings for clinical practice and/or further research: The short regime is less resource-intensive. Further larger studies are needed to confirm the efficacy of this short regime and to establish its cost-effectiveness.


Asunto(s)
Eclampsia/prevención & control , Sulfato de Magnesio/administración & dosificación , Preeclampsia , Resultado del Embarazo , Adulto , Puntaje de Apgar , Peso al Nacer , Relación Dosis-Respuesta a Droga , Femenino , Humanos , India/epidemiología , Recién Nacido , Trabajo de Parto Inducido , Sulfato de Magnesio/efectos adversos , Muerte Perinatal , Embarazo , Mortinato/epidemiología
6.
Niger J Clin Pract ; 21(3): 318-326, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29519980

RESUMEN

OBJECTIVES (BACKGROUND): Risk of dental injury from contact sports can be prevented by the use of mouthguards. Dentists provide excellent information regarding mouthguards. Thus, the aim was to assess the awareness among dentists regarding the same, the level of training in fabricating a mouthguard and whether they regularly recommend one for their athletically active patients. MATERIALS AND METHODS: This institutional cross-sectional survey was conducted in the Department of Orthodontics, Government Dental College, Kottayam, and Kerala, India. An online form was sent out to 1500 offices and departments in dental institutions through email with a time period of 1 month given to fill responses and was analyzed using descriptive statistics. RESULTS: A response from 640 was recorded; most of them had not received or had fabricated a mouthguard during their dental training or private practice, even though one-third recommended one to their athletically active patients with a lack of formal training being the reason for not routinely advocating mouthguard usage. Most were aware of more than one type of mouthguards and recommended customized one for the same, however, more than half were not aware of a different type intended for orthodontic patients. CONCLUSION: It is not a routine practice currently, among general dentists and specialists alike, in our country, to prescribe a mouthguard. It is time that the dental fraternity spread awareness for the prevention of injuries. A relook into the academic curriculum while advocating the use of customized mouthguards to patients due to contact sports is required.


Asunto(s)
Traumatismos en Atletas/prevención & control , Odontólogos/psicología , Conocimientos, Actitudes y Práctica en Salud , Protectores Bucales/estadística & datos numéricos , Traumatismos de los Dientes/prevención & control , Actitud del Personal de Salud , Concienciación , Estudios Transversales , Femenino , Humanos , India , Masculino , Nigeria , Percepción , Encuestas y Cuestionarios , Universidades
7.
Diabet Med ; 34(12): 1696-1700, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29048747

RESUMEN

AIM: To examine the extent to which offspring obesity-associated genetic risk explains the association between gestational diabetes mellitus and childhood adiposity. METHODS: We studied 282 children aged 7-12 years who were enrolled in the Exploring Perinatal Outcomes in Children Study. A genetic risk score for BMI was calculated as the count of 91 established BMI-raising risk alleles. Multivariable linear and logistic regression models were used to estimate associations between the offspring genetic risk score and exposure to gestational diabetes and childhood adiposity (BMI and waist circumference), adjusting for clinical and demographic covariates. The contribution of offspring genetic risk to associations between maternal gestational diabetes and childhood outcomes was estimated by comparing the regression coefficients for the gestational diabetes variable in models with and without the genetic risk score. RESULTS: The offspring BMI genetic risk score was associated with childhood BMI (P = 0.006) and waist circumference (P = 0.02), and marginally with gestational diabetes (P = 0.05). Offspring BMI genetic risk did not contribute significantly to associations between gestational diabetes and childhood BMI [7.7% (95% CI -3.3, 18.8)] or waist circumference [5.8% (95% CI -3.1, 14.8); P = 0.2 for both]. CONCLUSIONS: Offspring obesity genetic risk does not explain a significant proportion of the association between gestational diabetes exposure and childhood adiposity. The association between gestational diabetes and childhood adiposity is probably explained through alternative pathways, including direct intrauterine effects or a shared postnatal environment.


Asunto(s)
Adiposidad/genética , Diabetes Gestacional/epidemiología , Obesidad Infantil/epidemiología , Obesidad Infantil/genética , Efectos Tardíos de la Exposición Prenatal/epidemiología , Adulto , Peso al Nacer/fisiología , Niño , Estudios de Cohortes , Diabetes Gestacional/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Recién Nacido , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal/genética , Factores de Riesgo
8.
BMC Womens Health ; 17(1): 78, 2017 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-28893234

RESUMEN

BACKGROUND: Traditional practice after vaginal hysterectomy was to keep the vaginal pack and urinary catheter for 24 hours post operatively. But there were studies that prolonged cathterisation was associated with urinary infection. So this study was conducted to compare the post operative outcome when the urinary catheter and vaginal pack were removed after 3 hours and after 24 hours after surgery. METHODS: The study was done in the Department of Obstetrics and Gynecology, in a tertiary teaching institute of South India from September 2008 to March 2010. It was a randomised controlled trial involving 200 women undergoing vaginal surgery, who were randomly assigned to 2 groups - catheter and vaginal pack were removed either in 3 h in study group or were removed in 24 h in control group. The outcome of the study were vaginal bleeding, urinary retention, febrile morbidity, and urinary infection. RESULTS: There was no significant difference between the study and control groups with respect to vaginal bleeding (0 and 1%, p = 1), urinary retention (9 and 4%, p = 0.15), febrile morbidity (7 and 4%, p = 0.35), and urinary infection (26% in each group, p = 1.0). CONCLUSION: Keeping the urinary catheter and vaginal pack for 24 h following vaginal surgery does not offer any additional benefit against removing them after 3 h.


Asunto(s)
Histerectomía Vaginal/métodos , Vejiga Urinaria/fisiología , Cateterismo Urinario/normas , Retención Urinaria/fisiopatología , Infecciones Urinarias/prevención & control , Vagina/cirugía , Femenino , Humanos , India , Persona de Mediana Edad , Periodo Posoperatorio , Factores de Tiempo
9.
Arch Gynecol Obstet ; 296(1): 63-68, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28536812

RESUMEN

BACKGROUND: Preeclampsia is a multi-systemic, multi-organ dysfunction associated with increased maternal and perinatal complications. The presence of maternal ascites, a manifestation of endothelial dysfunction and increased capillary permeability, is shown to be associated with adverse outcomes. We aim to investigate the impact of maternal ascites on pregnancy outcome in women with severe preeclampsia. METHODS: A matched cohort study was conducted in a tertiary care teaching hospital in South India between March 2014 and March 2015. One hundred and twenty-one severe preeclamptic women with ascites formed the study cohort while age-, parity-, and gestational age-matched group of 121 severe preeclamptic women without ascites formed the control. Primary outcome was the composite maternal adverse outcome defined as the development of any of eclampsia, pulmonary edema, renal failure, or disseminated intravascular coagulation (DIC). Secondary outcome was the composite perinatal outcome defined as the occurrence of any of still birth, hypoxic ischemic encephalopathy or early neonatal death. RESULTS: Four maternal deaths occurred in the study group. The rates of pregnancies with composite maternal adverse outcome [42 vs 9% RR 4.6 (95% CI 2.5-8.4)] and composite perinatal adverse outcome [36 vs 17% RR 2.1, (95% CI 1.3-3.3)] were significantly more in ascites group than in control group. After adjusting for other confounding variables, ascites was independently associated with adverse maternal events [adjusted OR 16.40 (95% CI 2.88-93.31)] but not adverse perinatal outcome. CONCLUSION: In women with severe preeclampsia, maternal ascites is an independent risk factor for adverse maternal outcome.


Asunto(s)
Ascitis/complicaciones , Preeclampsia/diagnóstico , Adulto , Factores de Edad , Estudios de Cohortes , Femenino , Edad Gestacional , Humanos , India , Edad Materna , Paridad , Preeclampsia/patología , Embarazo , Resultado del Embarazo , Pronóstico , Factores de Riesgo
10.
Ann Oncol ; 27(8): 1546-56, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27117533

RESUMEN

BACKGROUND: Therapeutic resistance to gemcitabine in pancreatic ductal adenocarcinoma (PDAC) is attributed to various cellular mechanisms and signaling molecules that influence as a single factor or in combination. DESIGN: In this study, utilizing in vitro p21-activated kinase 1 (Pak1) overexpression and knockdown cell line models along with in vivo athymic mouse tumor xenograft models and clinical samples, we demonstrate that Pak1 is a crucial signaling kinase in gemcitabine resistance. RESULTS: Pak1 kindles resistance via modulation of epithelial-mesenchymal transition and activation of pancreatic stellate cells. Our results from gemcitabine-resistant and -sensitive cell line models showed that elevated Pak1 kinase activity is required to confer gemcitabine resistance. This was substantiated by elevated levels of phosphorylated Pak1 and ribonucleotide reductase M1 levels in the majority of human PDAC tumors when compared with normal. Delineation of the signaling pathway revealed that Pak1 confers resistance to gemcitabine by preventing DNA damage, inhibiting apoptosis and regulating survival signals via NF-κB. Furthermore, we found that Pak1 is an upstream interacting substrate of transforming growth factor ß-activated kinase 1-a molecule implicated in gemcitabine resistance. Molecular mechanistic studies revealed that gemcitabine docks with the active site of Pak1; furthermore, gemcitabine treatment induces Pak1 kinase activity both in vivo and in cell-free system. Finally, results from athymic mouse tumor models illustrated that Pak1 inhibition by IPA-3 enhances the cytotoxicity of gemcitabine and brings about pancreatic tumor regression. CONCLUSION: To our knowledge, this is the first study illustrating the mechanistic role of Pak1 in causing gemcitabine resistance via multiple signaling crosstalks, and hence Pak1-specific inhibitors will prove to be a better adjuvant with existing chemotherapy modality for PDAC.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Desoxicitidina/análogos & derivados , Quinasas p21 Activadas/genética , Adenocarcinoma/genética , Adenocarcinoma/patología , Animales , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Resistencia a Antineoplásicos/genética , Transición Epitelial-Mesenquimal/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Células Estrelladas Pancreáticas/efectos de los fármacos , Células Estrelladas Pancreáticas/patología , Ensayos Antitumor por Modelo de Xenoinjerto , Gemcitabina
11.
BJOG ; 123(1): 120-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26333044

RESUMEN

OBJECTIVE: To assess whether secondary prevention, which preemptively treats women with above-average postpartum bleeding, is non-inferior to universal prophylaxis. DESIGN: A cluster-randomised non-inferiority community trial. SETTING: Health sub-centres and home deliveries in the Bijapur district of Karnataka, India. POPULATION: Women with low-risk pregnancies who were eligible for delivery with an Auxiliary Nurse Midwife at home or sub-centre and who consented to be part of the study. METHODS: Auxiliary Nurse Midwifes were randomised to secondary prevention using 800 mcg sublingual misoprostol administered to women with postpartum blood loss ≥350 ml or to universal prophylaxis using 600 mcg oral misoprostol administered to all women during the third stage of labour. MAIN OUTCOME MEASURES: Postpartum haemoglobin ≤7.8 g/dl, mean postpartum blood loss and postpartum haemoglobin, postpartum haemorrhage rate, transfer to higher-level facilities, acceptability and feasibility of the intervention. RESULTS: Misoprostol was administered to 99.7% of women as primary prevention. In secondary prevention, 92 (4.7%) women had postpartum bleeding ≥350 ml, of which 90 (97.8%) received misoprostol. The proportion of women with postpartum haemoglobin ≤7.8 g/dl was 5.9 and 8.8% in secondary and primary prevention clusters, respectively [difference -2.9%, one-sided 95% confidence interval (CI) <1.3%]. Postpartum transfer and haemorrhage rates were low (<1%) in both groups. Shivering was more common in primary prevention clusters (P = 0.013). CONCLUSION: Secondary prevention of postpartum haemorrhage with misoprostol is non-inferior to universal prophylaxis based on the primary outcome of postpartum haemoglobin. Secondary prevention could be a good alternative to universal prophylaxis as it medicates fewer women and is an acceptable and feasible strategy at the community level. TWEETABLE ABSTRACT: Secondary prevention of postpartum haemorrhage with misoprostol is non-inferior to universal prophylaxis.


Asunto(s)
Misoprostol/administración & dosificación , Oxitócicos/administración & dosificación , Hemorragia Posparto/prevención & control , Prevención Primaria/métodos , Prevención Secundaria/métodos , Administración Oral , Adulto , Análisis por Conglomerados , Estudios de Factibilidad , Femenino , Parto Domiciliario , Humanos , India/epidemiología , Partería/educación , Embarazo
12.
Phys Chem Chem Phys ; 18(22): 14918-26, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27188211

RESUMEN

A detailed thermodynamic analysis of the solid and gas phases of the Mo-S-C-O-H system used for large area chemical vapor deposition (CVD) of MoS2 is presented and compared with experimental results. Given the multivariable nature of the problem, excellent agreement is observed. Deviations, observed from thermodynamic predictions, mainly at low temperatures and high flow rates have been highlighted and discussed. CVD phase diagrams which predict parameter windows in which pure MoS2 can be synthesized have been provided for important gas phase chemistries. Pure H2 as a carrier gas is shown to facilitate the largest contamination free process window. CO presence is shown to significantly reduce the nucleation rate and enable large island sizes but at the cost of carbon contamination. Oxygen leaks are shown to result in sulphur contamination. The absence of H2S during cooling is shown to yield Mo due to the reduction of MoS2 by hydrogen. Oxidation of Mo causes oxide contamination.

13.
Chem Soc Rev ; 44(17): 6035-58, 2015 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-25941907

RESUMEN

Rational design of small molecular gelators is an elusive and herculean task, despite the rapidly growing body of literature devoted to such gels over the past decade. The process of self-assembly, in molecular gels, is intricate and must balance parameters influencing solubility and those contrasting forces that govern epitaxial growth into axially symmetric elongated aggregates. Although the gelator-gelator interactions are of paramount importance in understanding gelation, the solvent-gelator specific (i.e., H-bonding) and nonspecific (dipole-dipole, dipole-induced and instantaneous dipole induced forces) intermolecular interactions are equally important. Solvent properties mediate the self-assembly of molecular gelators into their self-assembled fibrillar networks. Herein, solubility parameters of solvents, ranging from partition coefficients (log P), to Henry's law constants (HLC), to solvatochromic parameters (ET(30)), and Kamlet-Taft parameters (ß, α and π), and to Hansen solubility parameters (δp, δd, δh), are correlated with the gelation ability of numerous classes of molecular gelators. Advanced solvent clustering techniques have led to the development of a priori tools that can identify the solvents that will be gelled and not gelled by molecular gelators. These tools will greatly aid in the development of novel gelators without solely relying on serendipitous discoveries. These tools illustrate that the quest for the universal gelator should be left in the hands of Don Quixote and as researchers we must focus on identifying gelators capable of gelling classes of solvents as there is likely no one gelator capable of gelling all solvents.


Asunto(s)
Geles/química , Solventes/química , Modelos Químicos , Solubilidad , Termodinámica
14.
Soft Matter ; 11(26): 5188-91, 2015 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26021456

RESUMEN

This work describes a new method to selectively capture liposomes and other vesicle entities in the patterned pores of breath-figure polymer films. The process involves the deposition of a hydrophobe containing biopolymer in the pores of the breath figure, and the tethering of vesicles to the biopolymer through hydrophobic interactions. The process is versatile, can be scaled up and extended to the deposition of other functional materials in the pores of breath figures.


Asunto(s)
Liposomas/química , Polímeros/química , Aminas/química , Animales , Quitosano/química , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Conformación Molecular , Porosidad , alfa-Ciclodextrinas/química
15.
Analyst ; 140(16): 5724-31, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26160546

RESUMEN

Porous volumetric capture elements in microfluidic sensors are advantageous compared to planar capture surfaces due to higher reaction site density and decreased diffusion lengths that can reduce detection limits and total assay time. However a mismatch in refractive indices between the capture matrix and fluid within the porous interstices results in scattering of incident, reflected, or emitted light, significantly reducing the signal for optical detection. Here we demonstrate that perfusion of an index-matching fluid within a porous matrix minimizes scattering, thus enhancing optical signal by enabling the entire capture element volume to be probed. Signal enhancement is demonstrated for both fluorescence and absorbance detection, using porous polymer monoliths in a silica capillary and packed beds of glass beads within thermoplastic microchannels, respectively. Fluorescence signal was improved by a factor of 3.5× when measuring emission from a fluorescent compound attached directly to the polymer monolith, and up to 2.6× for a rapid 10 min direct immunoassay. When combining index matching with a silver enhancement step, a detection limit of 0.1 ng mL(-1) human IgG and a 5 log dynamic range was achieved. The demonstrated technique provides a simple method for enhancing optical sensitivity for a wide range of assays, enabling the full benefits of porous detection elements in miniaturized analytical systems to be realized.


Asunto(s)
Microfluídica/métodos , Refractometría , Humanos , Inmunoglobulina G/sangre , Límite de Detección , Porosidad
16.
Soft Matter ; 10(46): 9226-9, 2014 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-25315119

RESUMEN

Liposomal coatings are formed on films of a biopolymer, hydrophobically modified chitosan (hm-chitosan), containing dodecyl groups as hydrophobes along the polymer backbone. The alkyl groups insert themselves into the liposome bilayer through hydrophobic interactions and thus tether liposomes, leading to a densely packed liposome layer on the film surface. Such liposomal surfaces exhibit effective lubrication properties due to their high degree of hydration, and reduce the coefficient of friction to the biologically-relevant range. The compliancy and robustness of these tethered liposomes allow retention on the film surface upon repeated applications of shear. Such liposome coated films have potential applications in biolubrication.


Asunto(s)
Biopolímeros/química , Liposomas/química , 1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , 1,2-Dipalmitoilfosfatidilcolina/química , Quitosano/química , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Rastreo , Propiedades de Superficie
17.
Scand J Immunol ; 78(3): 275-84, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23713660

RESUMEN

Many patients with inflammatory bowel disease (IBD) are undergoing therapy with infliximab, an antibody specific for TNF. However, the exact mechanisms of action of infliximab are not completely understood. The aim of this study was to determine the in vitro effects of infliximab on blood T cells derived from anti-TNF therapy-naïve ulcerative colitis (UC) patients with clinically active disease. Peripheral blood mononuclear cells were stimulated polyclonally or by antigen in the presence or absence of infliximab. The T cell phenotype was investigated by flow cytometry, cytokine secretion was determined by ELISA, and cell proliferation was determined by thymidine assay or CFSE dye. Presence of infliximab resulted in reduced expression of CD25 in CD4(+) and CD8(+) T cell populations and inhibited secretion of IFN-γ, IL-13, IL-17A, TNF as well as granzyme A. Infliximab also suppressed CD4(+) and CD8(+) T cell proliferation. These effects of infliximab were recorded both in T cells activated by polyclonal and antigen-specific stimulation. The effects of infliximab on T cell apoptosis and induction of FOXP3(+) CD4(+) T regulatory cells were ambiguous and depended on the originating cellular source and/or the stimulation mode and strength. In conclusion, infliximab is able to reduce T cell activation as measured by CD25, proliferation and cytokine secretion in vitro from UC patients with clinically active disease. These data suggest that suppression of T cell activity may be important for infliximab-mediated disease remission in patients with UC.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD8-positivos/efectos de los fármacos , Colitis Ulcerosa/tratamiento farmacológico , Adulto , Anciano , Antiinflamatorios no Esteroideos/farmacología , Anticuerpos Monoclonales/farmacología , Apoptosis/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Proliferación Celular/efectos de los fármacos , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/metabolismo , Femenino , Factores de Transcripción Forkhead/metabolismo , Granzimas/metabolismo , Humanos , Infliximab , Interferón gamma/metabolismo , Interleucina-13/metabolismo , Interleucina-17/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Activación de Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Factores de Necrosis Tumoral/metabolismo , Adulto Joven
18.
Biomarkers ; 18(3): 196-203, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23557128

RESUMEN

CONTEXT: Endothelial function is abnormal in chronic obstructive pulmonary disease (COPD); whether endothelial dysfunction causes COPD is unknown. OBJECTIVE: Test associations of endothelial biomarkers with FEV1 using instrumental variables. METHODS: Among 26 907 participants with spirometry, ICAM-1, P-selectin, E-selectin and endothelin-1 were measured in subsets. RESULTS: ICAM-1 and P-selectin were inversely associated with FEV1 among European-Americans (-29 mL and -34 mL per standard deviation of log-transformed biomarker, p < 0.001), as was endothelin-1 among African-Americans (-22 mL, p = 0.008). Genetically-estimated ICAM-1 and P-selectin were not significantly associated with FEV1. The instrumental variable for endothelin-1 was non-informative. CONCLUSION: Although ICAM-1, P-selectin and endothelin-1 were inversely associated with FEV1, associations for ICAM-1 and P-selectin do not appear causal.


Asunto(s)
Endotelio Vascular/metabolismo , Expresión Génica , Pulmón/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/genética , Biomarcadores/metabolismo , Población Negra , Estudios de Cohortes , Selectina E/genética , Selectina E/metabolismo , Endotelina-1/genética , Endotelina-1/metabolismo , Endotelio Vascular/fisiopatología , Femenino , Humanos , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Selectina-P/genética , Selectina-P/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/etnología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Pruebas de Función Respiratoria , Espirometría , Población Blanca
19.
Biomed Res Int ; 2022: 8616535, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35993045

RESUMEN

The second largest cause of mortality worldwide is breast cancer, and it mostly occurs in women. Early diagnosis has improved further treatments and reduced the level of mortality. A unique deep learning algorithm is presented for predicting breast cancer in its early stages. This method utilizes numerous layers to retrieve significantly greater amounts of information from the source inputs. It could perform automatic quantitative evaluation of complicated image properties in the medical field and give greater precision and reliability during the diagnosis. The dataset of axillary lymph nodes from the breast cancer patients was collected from Erasmus Medical Center. A total of 1050 images were studied from the 850 patients during the years 2018 to 2021. For the independent test, data samples were collected for 100 images from 95 patients at national cancer institute. The existence of axillary lymph nodes was confirmed by pathologic examination. The feed forward, radial basis function, and Kohonen self-organizing are the artificial neural networks (ANNs) which are used to train 84% of the Erasmus Medical Center dataset and test the remaining 16% of the independent dataset. The proposed model performance was determined in terms of accuracy (Ac), sensitivity (Sn), specificity (Sf), and the outcome of the receiver operating curve (Roc), which was compared to the other four radiologists' mechanism. The result of the study shows that the proposed mechanism achieves 95% sensitivity, 96% specificity, and 98% accuracy, which is higher than the radiologists' models (90% sensitivity, 92% specificity, and 94% accuracy). Deep learning algorithms could accurately predict the clinical negativity of axillary lymph node metastases by utilizing images of initial breast cancer patients. This method provides an earlier diagnostic technique for axillary lymph node metastases in patients with medically negative changes in axillary lymph nodes.


Asunto(s)
Neoplasias de la Mama , Aprendizaje Profundo , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Femenino , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Biomed Res Int ; 2022: 3163496, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35711528

RESUMEN

Diabetic patients can also be identified immediately utilizing retinopathy photos, but it is a challenging task. The blood veins visible in fundus photographs are used in several disease diagnosis approaches. We sought to replicate the findings published in implementation and verification of a deep learning approach for diabetic retinopathy identification in retinal fundus pictures. To address this issue, the suggested investigative study uses recurrent neural networks (RNN) to retrieve characteristics from deep networks. As a result, using computational approaches to identify certain disorders automatically might be a fantastic solution. We developed and tested several iterations of a deep learning framework to forecast the progression of diabetic retinopathy in diabetic individuals who have undergone teleretinal diabetic retinopathy assessment in a basic healthcare environment. A collection of one-field or three-field colour fundus pictures served as the input for both iterations. Utilizing the proposed DRNN methodology, advanced identification of the diabetic state was performed utilizing HE detected in an eye's blood vessel. This research demonstrates the difficulties in duplicating deep learning approach findings, as well as the necessity for more reproduction and replication research to verify deep learning techniques, particularly in the field of healthcare picture processing. This development investigates the utilization of several other Deep Neural Network Frameworks on photographs from the dataset after they have been treated to suitable image computation methods such as local average colour subtraction to assist in highlighting the germane characteristics from a fundoscopy, thus, also enhancing the identification and assessment procedure of diabetic retinopathy and serving as a skilled guidelines framework for practitioners all over the globe.


Asunto(s)
Aprendizaje Profundo , Diabetes Mellitus , Retinopatía Diabética , Retinopatía Diabética/diagnóstico por imagen , Fondo de Ojo , Humanos , Redes Neurales de la Computación , Fotograbar/métodos
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