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1.
J Hepatol ; 78(3): 513-523, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-38133554

RESUMEN

BACKGROUND & AIMS: Selgantolimod (GS-9688) is a Toll-like receptor 8 (TLR8) agonist that suppresses HBV in vitro. In a phase II study, we evaluated the safety and efficacy of weekly selgantolimod treatment in virally suppressed individuals with chronic HBV taking oral antiviral treatment. METHODS: Forty-eight patients were randomized into two cohorts (hepatitis B e antigen [HBeAg]-positive and -negative [n = 24 each]) to receive oral selgantolimod 3 mg, 1.5 mg, or placebo (2:2:1) once weekly for 24 weeks while maintaining oral antivirals. The primary efficacy endpoint was the percentage of patients with a ≥1 log10 IU/ml decline in hepatitis B surface antigen (HBsAg) from baseline to week 24. Post-treatment, patients continued on oral antivirals for 24 weeks. RESULTS: The primary endpoint was reached by one participant, who was HBeAg-negative and received selgantolimod 1.5 mg. In contrast with placebo-treated patients (n = 9), only selgantolimod-treated patients (n = 39 total) had HBsAg declines greater than 0.1 log10 IU/ml at weeks 24 (18%, 7/39) and 48 (26%, 10/39), HBsAg loss (5%, 2/39 through 48 weeks), or HBeAg loss (16%, 3/19 through 48 weeks). The most common adverse events in selgantolimod-treated groups were nausea (46%), upper respiratory tract infection (23%), and vomiting (23%). Gastrointestinal disorders were mostly mild and transient. Selgantolimod induced transient dose-dependent increases in serum cytokines, including IL-12p40, IFN-γ, and IL-1RA, as well as rapid redistribution of some circulating immune cell subsets. CONCLUSION: Oral selgantolimod up to 3 mg once weekly for 24 weeks was generally safe and well tolerated and led to serologic changes associated with progression to durable cure in two individuals by week 48. GOV IDENTIFIER: NCT03491553. IMPACT AND IMPLICATIONS: The only robust criterion for stopping treatment in chronic hepatitis B is loss of hepatitis B surface antigen (known as functional cure), which is rare during nucleos(t)ide analogue therapy. It is likely that novel antiviral and immunomodulatory therapies will be needed to achieve finite functional cure. Selgantolimod is an oral Toll-like receptor 8 agonist that has shown antiviral activity in vitro as well as safety in a phase I clinical trial with weekly dosing. In this phase II study, selgantolimod therapy was associated with transient increases in serum cytokines, rapid redistribution of circulating immune cell subsets, modest reductions in HBsAg and HBeAg levels, and occasional loss of HBsAg (5%) and HBeAg (16%) among participants with chronic hepatitis B on nucleos(t)ide analogue therapy with viral suppression. Our results support continued development of selgantolimod as a component of a future hepatitis B cure regimen.


Asunto(s)
Antivirales , Hepatitis B Crónica , Receptor Toll-Like 8 , Humanos , Antivirales/uso terapéutico , Citocinas , Antígenos e de la Hepatitis B , Antígenos de Superficie de la Hepatitis B , Hepatitis B Crónica/tratamiento farmacológico , Receptor Toll-Like 8/agonistas , Resultado del Tratamiento
2.
Ultrason Imaging ; 45(3): 136-150, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37052393

RESUMEN

Cardiovascular disease serves as the leading cause of death worldwide. Calcification detection is considered an important factor in cardiovascular diseases. Currently, medical practitioners visually inspect the presence of calcification using intravascular ultrasound (IVUS) images. The study aims to detect the extent of calcification as belonging to class I, II as mild calcification, and class III, IV as dense calcification from IVUS images acquired at 40 MHz. To detect calcification, the features were extracted using improved AlexNet architecture and then were fed into machine learning classifiers. The experiments were carried out using 14 real IVUS pullbacks of 10 patients. Experimental results show that the combination of traditional machine learning with deep learning approaches significantly improves accuracy. The results show that support vector machines outperform all other classifiers. The proposed model is compared with two other pre-trained models GoogLeNet (98.8%), SqueezeNet (99.2%), and exhibits considerable improvement in classification accuracy (99.8%). In the future other models such as Vision Transformers could be explored with additional feature selection methods such as ReliefF, PSO, ACO, etc. to improve the overall accuracy of diagnosis.


Asunto(s)
Calcinosis , Aprendizaje Automático , Humanos , Ultrasonografía , Ultrasonografía Intervencional/métodos
3.
Hepatology ; 74(4): 1737-1749, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33704806

RESUMEN

BACKGROUND AND AIMS: In patients with chronic hepatitis B (CHB) infection, activation of toll-like receptor 8 may induce antiviral immunity and drive functional cure. Selgantolimod, a toll-like receptor 8 agonist, was evaluated in patients with CHB who were virally suppressed on oral antiviral treatment or viremic and not on oral antiviral treatment. APPROACH AND RESULTS: In this phase 1b study, patients were randomized 4:1 to receive either selgantolimod or placebo once weekly. Virally suppressed patients received either 1.5 mg (for 2 weeks) or 3 mg (for 2 weeks or 4 weeks). Viremic patients received 3 mg for 2 weeks. The primary endpoint was safety, as assessed by adverse events (AEs), laboratory abnormalities, and vital sign examination. Pharmacokinetic and pharmacodynamic parameters were assessed by plasma analysis. A total of 38 patients (28 virally suppressed, 10 viremic) were enrolled from six sites in Australia, New Zealand, and South Korea. Twenty patients (53%) experienced an AE and 32 (84%) had laboratory abnormalities, all of which were mild or moderate in severity. The most common AEs were headache (32%), nausea (24%), and dizziness (13%). With a half-life of 5 hours, no accumulation of selgantolimod was observed with multiple dosing. Selgantolimod induced transient dose-dependent increases in serum cytokines, including IL-12p40 and IL-1RA, which are important for the expansion and activity of multiple T- cell subsets and innate immunity. CONCLUSION: Selgantolimod was safe and well-tolerated in virally suppressed and viremic patients with CHB and elicited cytokine responses consistent with target engagement. Further studies with longer durations of selgantolimod treatment are required to evaluate efficacy.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B Crónica/tratamiento farmacológico , Hexanoles/uso terapéutico , Pirimidinas/uso terapéutico , Receptor Toll-Like 8/agonistas , Adulto , Mareo/inducido químicamente , Relación Dosis-Respuesta a Droga , Femenino , Cefalea/inducido químicamente , Hepatitis B Crónica/sangre , Hexanoles/farmacología , Humanos , Proteína Antagonista del Receptor de Interleucina 1/sangre , Subunidad p40 de la Interleucina-12/sangre , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Pirimidinas/farmacología , Respuesta Virológica Sostenida
4.
Int Orthop ; 44(4): 693-698, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31451848

RESUMEN

INTRODUCTION: Sternoclavicular joint tuberculosis is rare and has been presented in literature with few sporadic case reports or small case series. Rarity of the condition, nonspecific symptoms, difficulty to visualise the area on X-rays, and minimal clinical signs make diagnosis of sternoclavicular tuberculosis extremely difficult. Delay in diagnosis is therefore the common feature of all presented reports in literature. We here present our experience of treating 19 cases of sternoclavicular tuberculosis at our centre. MATERIALS AND METHOD: This is an observational study from 2010 to 2017 in a tertiary care referral hospital. All patients with clinical tenderness of sternoclavicular joint and shoulder joint pain of over three week duration were subjected to MRI. Patients who showed radiological lesions (radiography/MRI) were subjected to core biopsy under image guidance. A total of 26 patients had biopsy confirmed sternoclavicular tuberculosis (TB) during this period. RESULTS: All patients had improvement in shoulder function after treatment completion. Mean CSS pre-treatment was 29 which improved to mean of 8 after 18 months of ATT. Eight patients had excellent results, seven good, three fair, and one patient poor result. High initial ESR, late commencement of ATT from initial symptoms, and surgery of the involved joint were considered poor prognostic factors. DISCUSSION: Sternoclavicular tuberculosis is a rare disease with controversial etiology. Both haematogenous spread through suprascapular artery and contiguous spread through latent disease in apical lungs has been postulated. Delay in diagnosis is common to most reports in literature. Early MRI is useful in diagnosis of the lesion. The treatment for sternoclavicular joint in literature is controversial with proponents of both surgery and conservative management. CONCLUSION: Primary sternoclavicular tuberculosis is rare condition and requires a high index of suspicion for an early diagnosis. A focused sternoclavicular MRI and early biopsy may help in timely diagnosis. Early commencement of ATT has overall good clinical and functional results.


Asunto(s)
Mycobacterium tuberculosis/genética , Articulación del Hombro/diagnóstico por imagen , Dolor de Hombro/diagnóstico , Articulación Esternoclavicular/diagnóstico por imagen , Tuberculosis Osteoarticular/diagnóstico , Adulto , Antituberculosos/uso terapéutico , Biopsia , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Mycobacterium tuberculosis/aislamiento & purificación , Estudios Prospectivos , Radiografía , Enfermedades Raras/diagnóstico , Enfermedades Raras/patología , Resultado del Tratamiento , Tuberculosis Osteoarticular/tratamiento farmacológico , Tuberculosis Osteoarticular/patología
6.
Langmuir ; 33(51): 14709-14717, 2017 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-29211482

RESUMEN

Here, we present a controlled synthesis of Mn-doped ZnO nanoparticles (NPs) with predominantly nail-like shapes, whose formation occurs via tip-to-base-oriented attachment of initially formed nanopyramids, followed by leveling of sharp edges that lead to smooth single-crystalline "nails". This shape is prevalent in noncoordinating solvents such as octadecene and octadecane. Yet, the double bond in the former promotes oriented attachment. By contrast, Mn-doped ZnO NP synthesis in a weakly coordinating solvent, benzyl ether, results in dendritic structures because of random attachment of initial NPs. Mn-doped ZnO NPs possess a hexagonal wurtzite structure, and in the majority of cases, the NP surface is enriched with Mn, indicating a migration of Mn2+ ions to the NP surface during the NP formation. When the NP formation is carried out without the addition of octadecyl alcohol, which serves as a surfactant and a reaction initiator, large, concave pyramid dimers are formed whose attachment takes place via basal planes. UV-vis and photoluminescence spectra of these NPs confirm the utility of controlling the NP shape to tune electro-optical properties.

7.
BMC Plant Biol ; 15: 9, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25604693

RESUMEN

BACKGROUND: Brassica juncea var. Varuna is an economically important oilseed crop of family Brassicaceae which is vulnerable to abiotic stresses at specific stages in its life cycle. Till date no attempts have been made to elucidate genome-wide changes in its transcriptome against high temperature or drought stress. To gain global insights into genes, transcription factors and kinases regulated by these stresses and to explore information on coding transcripts that are associated with traits of agronomic importance, we utilized a combinatorial approach of next generation sequencing and de-novo assembly to discover B. juncea transcriptome associated with high temperature and drought stresses. RESULTS: We constructed and sequenced three transcriptome libraries namely Brassica control (BC), Brassica high temperature stress (BHS) and Brassica drought stress (BDS). More than 180 million purity filtered reads were generated which were processed through quality parameters and high quality reads were assembled de-novo using SOAPdenovo assembler. A total of 77750 unique transcripts were identified out of which 69,245 (89%) were annotated with high confidence. We established a subset of 19110 transcripts, which were differentially regulated by either high temperature and/or drought stress. Furthermore, 886 and 2834 transcripts that code for transcription factors and kinases, respectively, were also identified. Many of these were responsive to high temperature, drought or both stresses. Maximum number of up-regulated transcription factors in high temperature and drought stress belonged to heat shock factors (HSFs) and dehydration responsive element-binding (DREB) families, respectively. We also identified 239 metabolic pathways, which were perturbed during high temperature and drought treatments. Analysis of gene ontologies associated with differentially regulated genes forecasted their involvement in diverse biological processes. CONCLUSIONS: Our study provides first comprehensive discovery of B. juncea transcriptome under high temperature and drought stress conditions. Transcriptome resource generated in this study will enhance our understanding on the molecular mechanisms involved in defining the response of B. juncea against two important abiotic stresses. Furthermore this information would benefit designing of efficient crop improvement strategies for tolerance against conditions of high temperature regimes and water scarcity.


Asunto(s)
Productos Agrícolas/economía , Productos Agrícolas/genética , Sequías , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Planta de la Mostaza/genética , Estrés Fisiológico/genética , Temperatura , Perfilación de la Expresión Génica , Ontología de Genes , Anotación de Secuencia Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Control de Calidad , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Análisis de Secuencia de ARN , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transcriptoma
8.
Orig Life Evol Biosph ; 45(4): 411-26, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25952510

RESUMEN

Earth is the only known planet bestowed with life. Several attempts have been made to explore the pathways of the origin of life on planet Earth. The search for the chemistry which gave rise to life has given answers related to the formation of biomonomers, and their adsorption on solid surfaces has gained much attention for the catalysis and stabilization processes related to the abiotic chemical evolution of the complex molecules of life. In this communication, surface interactions of L-leucine (Leu) on smectite (SMT) group of clay (viz. bentonite and montmorillonite) and their divalent metal ion (Mg(2+), Ca(2+) and Cu(2+)) incorporated on SMT has been studied to find the optimal conditions of time, pH, and concentration at ambient temperature (298 K). The progress of adsorption was followed spectrophotometrically and further characterized by FTIR, SEM/EDS and XRD. Leu, a neutral/non polar amino acid, was found to have more affinity in its zwitterionic form towards Cu(2+)- exchanged SMT and minimal affinity for Mg(2+)- exchanged SMT. The vibrational frequency shifts of -NH3 (+) and -COO(-) favor Van der Waal's forces during the course of surface interaction. Quantum calculations using density functional theory (DFT) have been applied to investigate the absolute value of metal ion affinities of Leu (Leu-M(2+) complex, M = Mg(2+), Ca(2+), Cu(2+)) with the help of their physico-chemical parameters. The hydration effect on the relative stability and geometry of the individual species of Leu-M(2+) × (H2O)n, (n =2 and 4) has also been evaluated within the supermolecule approach. Evidence gathered from investigations of surface interactions, divalent metal ions affinities and hydration effects with biomolecules may be important for better understanding of chemical evolution, the stabilization of biomolecules on solid surfaces and biomolecular-metal interactions. These results may have implications for understanding the origin of life and the preservation of biomarkers.


Asunto(s)
Evolución Química , Leucina/química , Metales/química , Modelos Teóricos , Silicatos/química , Adsorción , Cationes Bivalentes/química , Exobiología
9.
Photochem Photobiol Sci ; 13(6): 929-38, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24727943

RESUMEN

In the present work we report the spectral and photophysical properties of 3-hydroxyisoquinoline in various protic/aprotic solvents. Our steady state and time resolved fluorescence data indicates that in the monomer form of 3HIQ phototautomerization can take place in the excited state through excited state intramolecular proton, while as per earlier suggestions phototautomerization in 3HIQ occurs in dimer or complex (in the presence of acetic acid) form. Moreover, we find rather slow tautomerization (occurring on the nanosecond scale). It is found that proton transfer occurs both in the ground as well as excited states and is controlled by the polarity of the solvent.

10.
Curr Pharm Des ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38874046

RESUMEN

Over the period of the preceding decade, artificial intelligence (AI) has proved an outstanding performance in entire dimensions of science including pharmaceutical sciences. AI uses the concept of machine learning (ML), deep learning (DL), and neural networks (NNs) approaches for novel algorithm and hypothesis development by training the machines in multiple ways. AI-based drug development from molecule identification to clinical approval tremendously reduces the cost of development and the time over conventional methods. The COVID-19 vaccine development and approval by regulatory agencies within 1-2 years is the finest example of drug development. Hence, AI is fast becoming a boon for scientific researchers to streamline their advanced discoveries. AI-based FDA-approved nanomedicines perform well as target selective, synergistic therapies, recolonize the theragnostic pharmaceutical stream, and significantly improve drug research outcomes. This comprehensive review delves into the fundamental aspects of AI along with its applications in the realm of pharmaceutical life sciences. It explores AI's role in crucial areas such as drug designing, drug discovery and development, traditional Chinese medicine, integration of multi-omics data, as well as investigations into drug repurposing and polypharmacology studies.

11.
AIDS ; 38(1): F1-F9, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37939141

RESUMEN

OBJECTIVE: The objective of this study was to assess the pharmacokinetics, safety, and efficacy and confirm the dose of once-daily bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF; B/F/TAF) during pregnancy. DESIGN: An open-label, multicenter, single-arm, phase 1b study (NCT03960645) was conducted in 33 virologically suppressed pregnant women with HIV-1. METHODS: Participants received B/F/TAF (50/200/25 mg) from the second or third trimester through ∼16 weeks postpartum. Steady-state maternal plasma pharmacokinetic samples were collected at the second and third trimesters and 6 and 12 weeks postpartum for BIC, FTC, and TAF. Neonates ( n  = 29) were followed from birth to 4-8 weeks with sparse washout pharmacokinetic sampling for BIC and TAF. The proportion of participants with HIV-1 RNA less than 50 copies/ml at delivery (missing = excluded) was evaluated. RESULTS: Mean areas under the concentration-time curve over the dosing interval (AUC tau ) for BIC, FTC, and TAF were lower during pregnancy versus postpartum but were closer to AUC tau values for nonpregnant adults with HIV reported in other studies. Geometric least-squares mean ratios for BIC, FTC, and TAF AUC tau during pregnancy versus postpartum ranged from 41 to 45%, 64 to 69% and 57 to 78%, respectively. Mean BIC trough concentrations during pregnancy were more than 6.5-fold greater than the protein-adjusted 95% effective concentration. In neonates, the median BIC half-life was 43 h. Virologic suppression was maintained in all adult participants throughout the study, with no virologic failure or treatment-emergent resistance to HIV-1, no discontinuations because of adverse events, and no perinatal transmission. CONCLUSION: Exposures to BIC, FTC, and TAF were lower during pregnancy than postpartum. However, mean BIC trough concentrations were maintained at levels indicative of efficacious exposure, and FTC/TAF data were concordant with published literature in this population. Pharmacokinetic and safety data, combined with maintenance of robust virologic suppression, suggest that once-daily B/F/TAF without dose adjustment is appropriate during pregnancy.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Seropositividad para VIH , Adulto , Femenino , Humanos , Recién Nacido , Embarazo , Fármacos Anti-VIH/efectos adversos , Combinación de Medicamentos , Emtricitabina , Compuestos Heterocíclicos con 3 Anillos/efectos adversos , Infecciones por VIH/tratamiento farmacológico , Seropositividad para VIH/tratamiento farmacológico , Mujeres Embarazadas
12.
Cancer Res ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38885087

RESUMEN

The genetic landscape of cancer cells can lead to specific metabolic dependencies for tumor growth. Dietary interventions represent an attractive strategy to restrict the availability of key nutrients to tumors. In this study, we identified that growth of a subset of melanoma was severely restricted by a rationally designed combination therapy of a stearoyl-CoA desaturase (SCD) inhibitor with an isocaloric low-oleic acid diet. Despite its importance in oncogenesis, SCD underwent monoallelic co-deletion along with PTEN on chromosome 10q in about 47.5% of melanoma, and the other SCD allele was methylated, resulting in very low SCD expression. While this SCD deficient subset was refractory to SCD inhibitors, the subset of PTEN wildtype melanoma that retained SCD was sensitive. As dietary oleic acid could potentially blunt the effect of SCD inhibitors, a low-oleic acid custom diet was combined with SCD inhibitor. The combination reduced monounsaturated fatty acids and increased saturated fatty acids, inducing robust apoptosis and growth suppression and inhibiting lung metastasis with minimal toxicity in preclinical mouse models of PTEN wildtype melanoma. When combined with anti-PD1 immunotherapy, the SCD inhibitor improved T cell functionality and further constrained melanoma growth in mice. Collectively, these results suggest that optimizing SCD inhibitors with diets low in oleic acid may offer a viable and efficacious therapeutic approach for improving melanoma treatment.

13.
Clin Cancer Res ; 30(10): 2068-2077, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38530160

RESUMEN

PURPOSE: High-grade gliomas (HGG) carry a poor prognosis, with glioblastoma accounting for almost 50% of primary brain malignancies in the elderly. Unfortunately, despite the use of multiple treatment modalities, the prognosis remains poor in this population. Our preclinical studies suggest that the presence of aromatase expression, encoded by CYP19A1, is significantly upregulated in HGGs. Remarkably, we find that letrozole (LTZ), an FDA-approved aromatase inhibitor, has marked activity against HGGs. PATIENTS AND METHODS: We conducted a phase 0/I single-center clinical trial (NCT03122197) to assess the tumoral availability, pharmacokinetics (PK), safety, and tolerability of LTZ in recurrent patients with HGG. Planned dose cohorts included 2.5, 5, 10, 12.5, 15, 17.5, and 20 mg of LTZ administered daily pre- and postsurgery or biopsy. Tumor samples were assayed for LTZ content and relevant biomarkers. The recommended phase 2 dose (R2PD) was determined as the dose that resulted in predicted steady-state tumoral extracellular fluid (ECF; Css,ecf) >2 µmol/L and did not result in ≥33% dose-limiting adverse events (AE) assessed using CTCAE v5.0. RESULTS: Twenty-one patients were enrolled. Common LTZ-related AEs included fatigue, nausea, musculoskeletal, anxiety, and dysphoric mood. No DLTs were observed. The 15 mg dose achieved a Css,ecf of 3.6 ± 0.59 µmol/L. LTZ caused dose-dependent inhibition of estradiol synthesis and modulated DNA damage pathways in tumor tissues as evident using RNA-sequencing analysis. CONCLUSIONS: On the basis of safety, brain tumoral PK, and mechanistic data, 15 mg daily is identified as the RP2D for future trials.


Asunto(s)
Neoplasias Encefálicas , Glioma , Letrozol , Clasificación del Tumor , Recurrencia Local de Neoplasia , Humanos , Letrozol/administración & dosificación , Letrozol/farmacocinética , Letrozol/uso terapéutico , Letrozol/efectos adversos , Femenino , Glioma/tratamiento farmacológico , Glioma/patología , Persona de Mediana Edad , Masculino , Anciano , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética
14.
Orig Life Evol Biosph ; 43(4-5): 331-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24402033

RESUMEN

In the present work, surface interaction of L-alanine (L-ala) has been investigated on hematite (α-Fe2O3), an abundant mineral on Mars, as a function of time (5 min-48 h), pH (4.0 and 6.20 ± 0.10) and concentration (1 × 10(-3) M-10 × 10(-3) M) with optical absorbance and energy-dispersive spectroscopy (EDS). Adsorption parameters (XM and KL) were calculated from Langmuir adsorption isotherms. L-alanine has maximum affinity (65.31 %) in its zwitterionic form at pH 6.20, while it is only 29.86 % adsorbed at pH 4.0. Possible astrobiological implications are discussed.


Asunto(s)
Alanina/química , Evolución Química , Compuestos Férricos/química , Minerales/química , Tensoactivos/química , Adsorción , Exobiología , Espectrometría por Rayos X
15.
Med J Armed Forces India ; 69(2): 151-5, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24600089

RESUMEN

BACKGROUND: Use of conjunctival autograft following excision of primary pterygium has reduced the recurrence rate. This study evaluates the efficiency of fibrin glue as compared to sutures in attaching the conjunctival autograft with reference to surgical time, post operative comfort and recurrence during follow up. METHODS: 60 patients with primary pterygium were included and divided into two groups. In the first group autograft was secured in place with help of 10-0 polyamide monofilament suture while in second group fibrin glue was used. Both the groups were compared in terms of operative time, post op comfort and recurrence. RESULTS: The average surgical time taken was 50.93 ± 4.96 min with suture group and 34.43 ± 4.94 min with fibrin glue group. Pain and foreign body sensation was markedly less with fibrin glue group. At the end of final follow up at 6 months, 3 cases (10%) from suture group and 1 case (3.33%) from fibrin group had recurrence. CONCLUSION: Fibrin glue is effective and safe for attaching conjunctival autograft during pterygium surgery. Although more number of recurrences were observed in suture group as compared to fibrin glue group the difference was not statistically significant (p 0.612).

16.
Eur J Obstet Gynecol Reprod Biol X ; 20: 100258, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37942027

RESUMEN

Background and objective: With increase in prevalence of obesity and an increasing trend in the birth of macrosomic infants, Institute of Medicine (IOM) guidelines pertaining to optimal gestational weight gain (GWG) required for positive pregnancy outcome were revised in 1990 and 2009. Since, in the Indian scenario, no recommendations exist for optimum GWG for obese (OB) and overweight (OW) women, we assessed the pattern of GWG w.r.t Institute of Medicine (IOM), 2009 among the subjects with different body mass index (BMI). Study design: Present data were a part of a longitudinal observational study wherein, 312 pregnant women (≤12th week of gestation) attending private antenatal clinics were followed till term and their weight was monitored regularly at pre-determined intervals i.e., 12th-14th, 18th-20th, 24th-26th, 30th-32nd, 36th + week of gestation and compared w.r.t IOM guidelines 2009. Results: 66.37 %, 57.89 % and 11.69 % of OB, OW and normal weight (NW) subjects respectively had weight gain exceeding their GWG limits. About 5 %,10.53 %, 33.77 % of OB, OW and NW subjects respectively had gained weight less than GWG limits (p = 0.000***). Conclusion: An increase in GWG inadequacy with increase in BMI and pronounced variations in GWG among OB and OW subjects underscore the necessity to monitor GWG especially among the subjects with high BMI.

17.
J Pharm Bioallied Sci ; 15(Suppl 2): S1266-S1269, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37694017

RESUMEN

Objective: To analyze the incidence of retinopathy of prematurity (ROP) among preterm neonates who were born small for gestational age (SGA) and appropriate for gestational age (AGA). Materials and Methods: A prospective cohort study among preterm neonates born <34 weeks of gestational age (GA) and <2000 grams birth weight (BW) was conducted. The neonates were divided into AGA and SGA group. Incidence of ROP and risk factors was compared among the groups. Result: 290 neonates were screened [AGA: 240 (82.8%); SGA: 50 (17.2%)]. The mean birth-weight and gestational age were 1510.7 ± 390.64 grams and 31.4 ± 4.8 weeks, respectively. The incidence of ROP in AGA and SGA was 30.2% and 33%, respectively (P = 0.58), whereas the incidence of type 1 ROP in AGA and SGA was 14% and 19% (P = 0.41). Male sex, anemia, oxygen administration, surfactant administration, sepsis, and PIH were independent significant risk factors for ROP on multivariate analysis. Conclusion: This study showed that both AGA and SGA premature infants have similar incidence of ROP. SGA is not an independent risk factor for ROP.

18.
Cardiovasc Eng Technol ; 14(2): 264-295, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36650320

RESUMEN

Intravascular Ultrasound images (IVUS) is a useful guide for medical practitioners to identify the vascular status of coronary arteries in human beings. IVUS is a unique intracoronary imaging modality that is used as an adjunct to angioplasty to view vessel structures using a catheter with high resolutions. Segmentation of IVUS images has always remained a challenging task due to various impediments, for example, similar tissue components, vessel structures, and artifacts imposed during the acquisition process. Many researchers have applied various techniques to develop standard methods of image interpretation, however, the ultimate goal is still elusive to most researchers. This challenge was presented at the MICCAI- Computing and Visualization for (Intra)Vascular Imaging (CVII) workshop in 2011. This paper presents a major review of recently reported work in the field, with a detailed analysis of various segmentation techniques applied in IVUS, and highlights the directions for future research. The findings recommend a reference database with a larger number of samples acquired at varied transducer frequencies with special consideration towards complex lesions, suitable validation metrics, and ground-truth definition as a standard against which to compare new and current algorithms.


Asunto(s)
Vasos Coronarios , Ultrasonografía Intervencional , Humanos , Vasos Coronarios/diagnóstico por imagen , Ultrasonografía Intervencional/métodos , Ultrasonografía/métodos , Algoritmos
19.
Phys Eng Sci Med ; 46(2): 773-786, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37039978

RESUMEN

Intravascular Ultrasound (IVUS) is a medical imaging modality widely used for the detection and treatment of coronary heart disease. The detection of vascular structures is extremely important for accurate treatment procedures. Manual detection of lumen and calcification is very time-consuming and requires technical experience. Ultrasound imaging suffers from the generation of artifacts which obstructs the clear delineation among structures. Considering, the need, to provide special attention to crucial areas, convolutional block attention modules (CBAM) is integrated into an encoder-decoder-based U-Net architecture along with Atrous Spatial Pyramid Pooling (ASPP) to detect vessel components: lumen, calcification and shadow borders. The attention modules prove effective in dealing with areas of special attention by assigning additional weights to crucial channels and preserving spatial features. The IVUS data of 12 patients undergoing the treatment is taken for this study. The novelty of the model design is such that it is able to detect the lumen area in the presence/absence of calcification and bifurcation artifacts too. Also, the model efficiently detects the calcification area even in case of severely complex lesions with shadows behind them. The main contribution of the work is that IVUS images of varying degrees of calcification till 360° are also considered in this work, which is usually neglected in previous studies. The experimental results of 1097 IVUS images of 12 patients resulted in meanIoU (0.7894 ± 0.011), Dice Coefficient (0.8763 ± 0.070), precision (0.8768 ± 0.069) and recall (0.8774 ± 0.071) of the proposed model CADNet which show the model's effectiveness relative to other state-of-the art methods.


Asunto(s)
Enfermedad de la Arteria Coronaria , Ultrasonografía Intervencional , Humanos , Ultrasonografía Intervencional/métodos , Ultrasonografía/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen
20.
J Pharm Bioallied Sci ; 15(Suppl 2): S1257-S1261, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37694002

RESUMEN

Aims and Objectives: To determine the choroidal thickness (mainly subfoveal) using spectral domain optical coherence tomography (SD-OCT) in amblyopic eyes and to compare it with the choroidal thickness (CT) of healthy fellow eyes. Materials and Methods: In this prospective study, 140 eyes of 70 patients (aged 5-40 years) with strabismic and anisometropic amblyopia were examined using enhanced depth imaging (EDI) mode in SD-OCT. The CT was measured directly below the fovea and six other locations: 500 µ, 1000 µ, and 1500 µ from fovea in both nasal and temporal quadrants. Results: The mean age of the patients was 22.5 ± 11.2 years. The mean Best Corrected Visual Acuity (BCVA) in the amblyopic eyes was 0.87 ± 0.47 logMAR and 0 ± 0.02 logMAR in control eyes. The average subfoveal CT was 341.73 ± 60.39 µm in the amblyopic eyes and 314.77 ± 48.12 µm in the fellow eyes. Subgroup analysis showed that the patients with anisometropic amblyopia had a significantly thicker choroid as compared to the fellow healthy eyes (P = 0.00), whereas in strabismic amblyopic eyes, this difference was not significantly significant (P = 0.064). Conclusion: Significant choroidal thickening was observed in subjects with amblyopia, which may contribute to the amblyopia pathogenesis and this could be used as a diagnostic parameter for amblyopia. These changes were more pronounced in patients with anisometropic amblyopia than strabismic amblyopia.

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