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1.
Paediatr Int Child Health ; 44(1): 24-29, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38482867

RESUMEN

INTRODUCTION: Raised serum bilirubin levels can cause kernicterus, and premature infants are at increased risk owing to metabolic immaturity. The standard treatment for neonatal jaundice is phototherapy, but probiotics alone can reduce the duration of phototherapy and hospitalisation. OBJECTIVES: To determine the effectiveness of phototherapy with and without probiotics for the treatment of indirect hyperbilirubinaemia in preterm neonates. PATIENTS AND METHODS: The open-labelled randomised controlled trial was conducted from January 2022 to January 2023 in the neonatal unit of the University of Lahore Teaching Hospital, Pakistan. A total of 76 preterm neonates who fulfilled the selection criteria were included and divided into two groups. Both groups received standard phototherapy. In Group B, a probiotic (Saccharomyces boulardii) 125 mg, twice daily, orally (in 5 cc of whichever milk the infant was receiving) was given until discharge from hospital. The primary outcome measurements were the duration of phototherapy and the length of hospitalisation. RESULTS: The mean (SD) duration of phototherapy was 36.55 (14.25) hours in Group A and 24.61 (9.25) hours in Group B (p <0.05). The mean (SD) duration of hospital stay was 47.36 (16.51) hours in Group A and 33.13 (8.93) hours in Group B (p <0.05). CONCLUSION: Oral probiotics (Saccharomyces boulardii) have a significant effect on the duration of phototherapy for neonatal hyperbilirubinaemia, and they decrease the chances of nosocomial infection. Exploration of clinical outcomes by investigating faecal flora and undertaking large randomised controlled trials of various probiotics are needed. ABBREVIATIONS: ABE: acute bilirubin encephalopathy; CNS: central nervous system; GA: gestational age; IVIG: intravenous immunoglobulin; KSD: kernicterus; NNU: neonatal unit; RCT: randomised controlled trial; S. boulardii: Saccharomyces boulardii.


Asunto(s)
Hiperbilirrubinemia Neonatal , Recien Nacido Prematuro , Fototerapia , Probióticos , Humanos , Probióticos/administración & dosificación , Probióticos/uso terapéutico , Recién Nacido , Fototerapia/métodos , Femenino , Masculino , Hiperbilirrubinemia Neonatal/terapia , Resultado del Tratamiento , Pakistán
2.
Front Mol Biosci ; 8: 716735, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34765641

RESUMEN

V-domain Ig suppressor of T cell activation (VISTA) is an immune checkpoint and is a type I transmembrane protein. VISTA is linked to immunotherapy resistance, and it is a potential immune therapeutic target, especially for triple-negative breast cancer. It expresses at a high concentration in regulatory T cells and myeloid-derived suppressor cells, and its functional blockade is found to delay tumor growth. A useful medicinal plant database for drug designing (MPD3), which is a collection of phytochemicals from diverse plant families, was employed in virtual screening against VISTA to prioritize natural inhibitors against VISTA. Three compounds, Paratocarpin K (PubChem ID: 14187087), 3-(1H-Indol-3-yl)-2-(trimethylazaniumyl)propanoate (PubChem ID: 3861164), and 2-[(5-Benzyl-4-ethyl-1,2,4-triazol-3-yl)sulfanylmethyl]-5-methyl-1,3,4-oxadiazole (PubChem ID: 6494266), having binding energies stronger than -6 kcal/mol were found to have two common hydrogen bond interactions with VISTA active site residues: Arg54 and Arg127. The dynamics of the compound-VISTA complexes were further explored to infer binding stability of the systems. Results revealed that the compound 14187087 and 6494266 systems are highly stable with an average RMSD of 1.31 Å. Further affirmation on the results was achieved by running MM-GBSA on the MD simulation trajectories, which re-ranked 14187087 as the top-binder with a net binding energy value of -33.33 kcal/mol. In conclusion, the present study successfully predicted natural compounds that have the potential to block the function of VISTA and therefore can be utilized further in experimental studies to validate their real anti-VISTA activity.

3.
Comput Biol Med ; 138: 104929, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34655900

RESUMEN

Cholera is a severe small intestine bacterial disease caused by consumption of water and food contaminated with Vibrio cholera. The disease causes watery diarrhea leading to severe dehydration and even death if left untreated. In the past few decades, V. cholerae has emerged as multidrug-resistant enteric pathogen due to its rapid ability to adapt in detrimental environmental conditions. This research study aimed to design inhibitors of a master virulence gene expression regulator, HapR. HapR is critical in regulating the expression of several set of V. cholera virulence genes, quorum-sensing circuits and biofilm formation. A blind docking strategy was employed to infer the natural binding tendency of diverse phytochemicals extracted from medicinal plants by exposing the whole HapR structure to the screening library. Scoring function criteria was applied to prioritize molecules with strong binding affinity (binding energy < -11 kcal/mol) and as such two compounds: Strychnogucine A and Galluflavanone were filtered. Both the compounds were found favourably binding to the conserved dimerization interface of HapR. One rare binding conformation of Strychnogucine A was noticed docked at the elongated cavity formed by α1, α4 and α6 (binding energy of -12.5 kcal/mol). The binding stability of both top leads at dimer interface and elongated cavity was further estimated using long run of molecular dynamics simulations, followed by MMGB/PBSA binding free energy calculations to define the dominance of different binding energies. In a nutshell, this study presents computational evidence on antibacterial potential of phytochemicals capable of directly targeting bacterial virulence and highlight their great capacity to be utilized in the future experimental studies to stop the evolution of antibiotic resistance evolution.


Asunto(s)
Vibrio cholerae , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Fitoquímicos , Percepción de Quorum , Vibrio cholerae/genética , Vibrio cholerae/metabolismo
4.
Drug Dev Res ; 82(8): 1169-1181, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33983647

RESUMEN

Urease plays a significant role in the pathogenesis of urolithiasis pyelonephritis, urinary catheter encrustation, hepatic coma, hepatic encephalopathy, and peptic acid duodenal ulcers. Salvinia molesta was explored to identify new bioactive compounds with particular emphasis on urease inhibitors. The aqueous methanol extract was fractionated using solvents of increasing polarity. A series of column chromatography and later HPLC were performed on butanol extract. The structures of the resulting pure compounds were resolved using NMR (1D and 2D), infrared, and mass spectroscopy. The novel isolate was evaluated for antioxidant activity (using DPPH, superoxide anion radical scavenging, oxidative burst, and Fe+2 chelation assays), anti-glycation behavior, anticancer activity, carbonic anhydrase inhibition, phosphodiesterase inhibition, and urease inhibition. One new glucopyranose derivative 6'-O-(3,4-dihydroxybenzoyl)-4'-O-(4-hydroxybenzoyl)-α/ß-D-glucopyranoside (1) and four known glycosides were identified. Glycoside 1 demonstrated promising antioxidant potential with IC50 values of 48.2 ± 0.3, 60.3 ± 0.6, and 42.1 ± 1.8 µM against DPPH, superoxide radical, and oxidative burst, respectively. Its IC50 in the Jack bean urease inhibition assay was 99.1 ± 0.8 µM. The mechanism-based kinetic studies presented that compound 1 is a mixed-type inhibitor of urease with a Ki value of 91.8 ± 0.1 µM. Finally, molecular dynamic simulations exploring the binding mode of compound 1 with urease provided quantitative agreement between estimated binding free energies and the experimental results. The studies corroborate the use of compound 1 as a lead for QSAR studies as an antioxidant and urease inhibitor. Moreover, it needs to be further evaluated through the animal model, that is, in vivo or tissue culture-based ex-vivo studies, to establish their therapeutic potential against oxidative stress phosphodiesterase-II and urease-induced pathologies.


Asunto(s)
Antioxidantes/aislamiento & purificación , Extractos Vegetales/análisis , Tracheophyta/química , Ureasa/antagonistas & inhibidores , Antioxidantes/farmacología , Inhibidores Enzimáticos/aislamiento & purificación , Mediciones Luminiscentes , Simulación del Acoplamiento Molecular , Inhibidores de Fosfodiesterasa/aislamiento & purificación , Ureasa/química
5.
Sci Rep ; 11(1): 1708, 2021 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-33462261

RESUMEN

Ifosfamide is a widely used chemotherapeutic agent having broad-spectrum efficacy against several tumors. However, nephro, hepato, neuro cardio, and hematological toxicities associated with ifosfamide render its use limited. These side effects could range from organ failure to life-threatening situations. The present study aimed to evaluate the attenuating efficiency of Berberis vulgaris root extract (BvRE), a potent nephroprotective, hepatoprotective, and lipid-lowering agent, against ifosfamide-induced toxicities. The study design comprised eight groups of Swiss albino rats to assess different dose regimes of BvRE and ifosfamide. Biochemical analysis of serum (serum albumin, blood urea nitrogen, creatinine, alanine transaminase, aspartate transaminase, alkaline phosphatase, lactate dehydrogenase, total cholesterol, and triglycerides) along with complete blood count was performed. Kidney, liver, brain, and heart tissue homogenates were used to find malondialdehyde, catalase, and glutathione S-transferase levels in addition to the acetylcholinesterase of brain tissue. The results were further validated with the help of the histopathology of the selected organs. HeLa cells were used to assess the effect of BvRE on ifosfamide cytotoxicity in MTT assay. The results revealed that pre- and post-treatment regimens of BvRE, as well as the combination therapy exhibited marked protective effects against ifosfamide-induced nephro, hepato, neuro, and cardiotoxicity. Moreover, ifosfamide depicted a synergistic in vitro cytotoxic effect on HeLa cells in the presence of BvRE. These results corroborate that the combination therapy of ifosfamide with BvRE in cancer treatment can potentiate the anticancer effects of ifosfamide along with the amelioration of its conspicuous side effects.


Asunto(s)
Berberis/química , Encéfalo/efectos de los fármacos , Ifosfamida/farmacología , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Berberis/metabolismo , Recuento de Células Sanguíneas , Encéfalo/metabolismo , Encéfalo/patología , Supervivencia Celular/efectos de los fármacos , Células HeLa , Humanos , Riñón/metabolismo , Riñón/patología , Hígado/metabolismo , Hígado/patología , Masculino , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Ratas
6.
Comput Biol Chem ; 89: 107376, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32979815

RESUMEN

Human ubiquitin carboxyl-terminal hydrolase-2 (USP2) inhibitors, such as thiopurine analogs, have been reported to inhibit SARS-CoV papain-like proteases (PLpro). The PLpro have significant functional implications in the innate immune response during SARS-CoV-2 infection and considered an important antiviral target. Both proteases share strikingly similar USP fold with right-handed thumb-palm-fingers structural scaffold and conserved catalytic triad Cys-His-Asp/Asn. In this urgency situation of COVID-19 outbreak, there is a lack of in-vitro facilities readily available to test SARS-CoV-2 inhibitors in whole-cell assays. Therefore, we adopted an alternate route to identify potential USP2 inhibitor through integrated in-silico efforts. After an extensive virtual screening protocol, the best compounds were selected and tested. The compound Z93 showed significant IC50 value against Jurkat (9.67 µM) and MOTL-4 cells (11.8 µM). The binding mode of Z93 was extensively analyzed through molecular docking, followed by MD simulations, and molecular interactions were compared with SARS-CoV-2. The relative binding poses of Z93 fitted well in the binding site of both proteases and showed consensus π-π stacking and H-bond interactions with histidine and aspartate/asparagine residues of the catalytic triad. These results led us to speculate that compound Z93 might be the first potential chemical lead against SARS-CoV-2 PLpro, which warrants in-vitro evaluations.


Asunto(s)
Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Inhibidores de Proteasa de Coronavirus/farmacología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/enzimología , Ubiquitina Tiolesterasa/antagonistas & inhibidores , Antivirales/química , COVID-19/virología , Línea Celular Tumoral , Proteasas 3C de Coronavirus/metabolismo , Inhibidores de Proteasa de Coronavirus/química , Evaluación Preclínica de Medicamentos , Humanos , Células Jurkat , Modelos Moleculares , Estructura Molecular , Ubiquitina Tiolesterasa/metabolismo
7.
Mol Cell Biochem ; 472(1-2): 67-78, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32524320

RESUMEN

We evaluated the effects of Rubus tereticaulis in healing process by determining the total carbonyl content, collagen synthesis, and total protein level on rat wounded tissues. Wounds were performed in the back of 54 Wistar rats, using a biopsy punch instrument with 0.6 mm in diameter. Rats were randomly divided into three groups: (i) un-treatment wounds group served as "controls", (ii) Madecassol® used as "positive control" group, and (iii) the application of topical cream of R. tereticaulis served as "treatment" group of wound healing. The animals were killed at the end of experiment under anesthesia with ketamine, and tissue samples were collected for the evaluation at three times intervals (3rd, 7th, and 14th day). The wounded areas were analyzed for total carbonyl content, collagen, and total protein levels by HPLC, ELISA, and spectrophotometric methods, respectively. Total carbonyl content in the treatment group was significantly lower in comparison with control group on 3rd day (2.839 ± 0.438 vs. 3.216 ± 0.216 nmol carbonyl/mol protein; p < 0.5) and 14th days (4.222 ± 0.128 vs. 4.784 ± 0.077 nmol carbonyl/mol protein; p < 0.05), respectively. New collagen formation on the wound sites after the initial injury was noted in the treated and positive control groups (5.310 ± 0.331 vs. 5.164 ± 0.377 mg collagen/g wet tissue) at the 3rd day than control group (2.180 ± 0.718 mg collagen/g wet tissue, p < 0.01), and in treated and positive control groups at 7th day (9.654 ± 0.201, 9.053 ± 1.062 mg collagen/g wet tissue, p < 0.01); and in treated and positive control groups at 14th day (8.469 ± 0.236, 5.631 ± 0.531 mg collagen/g wet tissue, respectively; p < 0.05) in comparison with the control group. Total protein level of samples did not change significantly between the groups. Thus, application of R. tereticaulis ameliorated the wound healing process in rats as it facilitated collagen formation through healing of the wound. Evaluating total carbonyl content by HPLC could be useful as an advance procedure for quantification of healing.


Asunto(s)
Colágeno/metabolismo , Extractos Vegetales/farmacología , Carbonilación Proteica/efectos de los fármacos , Proteínas/metabolismo , Rubus/química , Cicatrización de Heridas/efectos de los fármacos , Animales , Femenino , Masculino , Ratas , Ratas Wistar
8.
Antioxidants (Basel) ; 8(7)2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31331076

RESUMEN

Members of genus Pteris have their established role in the traditional herbal medicine system. In the pursuit to identify its biologically active constituents, the specie Pteris cretica L. (P. cretica) was selected for the bioassay-guided isolation. Two new maleates (F9 and CB18) were identified from the chloroform extract and the structures of the isolates were elucidated through their spectroscopic data. The putative targets, that potentially interact with both of these isolates, were identified through reverse docking by using in silico tools PharmMapper and ReverseScreen3D. On the basis of reverse docking results, both isolates were screened for their antioxidant, acetylcholinesterase (AChE) inhibition, α-glucosidase (GluE) inhibition and antibacterial activities. Both isolates depicted moderate potential for the selected activities. Furthermore, docking studies of both isolates were also studied to investigate the binding mode with respective targets followed by molecular dynamics simulations and binding free energies. Thereby, the current study embodies the poly-pharmacological potential of P. cretica.

9.
Biomolecules ; 9(4)2019 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-30925835

RESUMEN

Tumorigenesis in humans is a multistep progression that imitates genetic changes leading to cell transformation and malignancy. Oncogenic kinases play a central role in cancer progression, rendering them putative targets for the design of anti-cancer drugs. The presented work aims to identify the potential multi-target inhibitors of oncogenic receptor tyrosine kinases (RTKs) and serine/threonine kinases (STKs). For this, chemoinformatics and structure-based virtual screening approaches were combined with an in vitro validation of lead hits on both cancerous and non-cancerous cell lines. A total of 16 different kinase structures were screened against ~739,000 prefiltered compounds using diversity selection, after which the top hits were filtered for promising pharmacokinetic properties. This led to the identification of 12 and 9 compounds against RTKs and STKs, respectively. Molecular dynamics (MD) simulations were carried out to better comprehend the stability of the predicted hit kinase-compound complexes. Two top-ranked compounds against each kinase class were tested in vitro for cytotoxicity, with compound F34 showing the most promising inhibitory activity in HeLa, HepG2, and Vero cell lines with IC50 values of 145.46 µM, 175.48 µM, and 130.52 µM, respectively. Additional docking of F34 against various RTKs was carried out to support potential multi-target inhibition. Together with reliable MD simulations, these results suggest the promising potential of identified multi-target STK and RTK scaffolds for further kinase-specific anti-cancer drug development toward combinatorial therapies.


Asunto(s)
Antineoplásicos/farmacología , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/metabolismo , Animales , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Evaluación Preclínica de Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Células HeLa , Células Hep G2 , Humanos , Estructura Molecular , Inhibidores de Proteínas Quinasas/química , Células Vero
10.
Artículo en Inglés | MEDLINE | ID: mdl-28533155

RESUMEN

Robotic-assisted laparoscopic surgery is the most common approach for the treatment of early-stage endometrial and cervical cancers in the US. Surgical staging requires pelvic and often aortic lymphadenectomy, depending on the primary tumor characteristics. Pelvic and aortic lymphadenectomy procedures may also be indicated for debulking of larger metastases to improve disease control. The infra-renal basin is an important anatomic site of metastasis from pelvic tumors, and robotic dissection techniques for this site have been described. In recent years, sentinel lymph node (SLN) mapping has been adopted into the National Comprehensive Cancer Network guidelines' surgical algorithm for uterine and cervical cancers. SLN mapping has higher sensitivity for the detection of nodal metastasis, despite removing fewer lymph nodes, and potentially reduces morbidities such as lower extremity lymphedema. This article reviews current robotic pelvic and para-aortic lymphadenectomy dissection techniques for endometrial and cervical cancers and discusses the recent integration of pelvic SLN mapping in the surgical algorithm.


Asunto(s)
Neoplasias de los Genitales Femeninos/cirugía , Laparoscopía/métodos , Escisión del Ganglio Linfático/métodos , Metástasis Linfática/diagnóstico , Procedimientos Quirúrgicos Robotizados/métodos , Femenino , Neoplasias de los Genitales Femeninos/patología , Humanos , Estadificación de Neoplasias/métodos , Pelvis/patología , Pelvis/cirugía , Ganglio Linfático Centinela/patología , Ganglio Linfático Centinela/cirugía , Biopsia del Ganglio Linfático Centinela/métodos
11.
Crit Rev Food Sci Nutr ; 55(7): 919-29, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24915375

RESUMEN

Tomato (Solanum lycopersicum) is one of the most essential herbaceous plants that have been probed against various life sight related disorders owing to array of phytochemicals. It is important source of vitamin C, potassium, folic acid, and carotenoids, such as lycopene. Carotenoids are the pigments synthesized during fruit ripening and responsible for the final red color of the tomato. Consumption of tomato and tomato-based products contribute to the absorption of carotenoids and lycopenes in human serum. Lycopene is chemically acyclic carotene with 11 conjugated double bonds, normally in transconfiguration while isomerization occur in blood plasma for its better absorption. It has ability for adenosine deaminase inhibition that plays important role in the regression of tumor. Tomato also contain other active compounds, namely, neoxanthin, lutein, α-cryptoxanthin, α-carotene, ß-carotene, cyclolycopene, and ß-carotene 5, 6-epoxide. These components provide synergistic effect against various threats but still need further attention of the researchers. Both in vitro and in vivo studies have elucidated the potential of tomato against variety of metabolic syndromes. Latest research highlights the relationship between consuming tomato and its products with reduced risk of various maladies like obesity, hyperglycemic and hypercholesterolemic attributes, cardiovascular disorders, and cancer insurgences. Moreover, tomato and its bioactive components hold potential to become effective modules in diet-based regimens; however, integrated research and meta-analysis are still required to enhance meticulousness.


Asunto(s)
Carotenoides/química , Carotenoides/metabolismo , Terapia Nutricional/métodos , Valor Nutritivo , Solanum lycopersicum/química , Humanos , Absorción Intestinal/fisiología , Licopeno , Solanum lycopersicum/metabolismo , Síndrome Metabólico/dietoterapia , Neoplasias/dietoterapia
12.
Drug Discov Today ; 20(1): 65-75, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25205348

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a debilitating disease characterized by progressive loss of voluntary motor neurons leading to muscle atrophy, weight loss and respiratory failure. Evidence suggests that inflammation, oxidative stress, mitochondrial dysfunction, apoptosis, glutamate excitotoxicity and proteasomal dysfunction are all responsible for ALS pathogenesis. We review neuroprotective agents with the ability to reduce ALS-related bodyweight loss, summarize the various therapies tested on animal models targeting the proposed molecular mechanisms, compare their effects on bodyweight loss, muscle damage, disease onset, duration and survival, and analyze their structure-activity relationships, with the overall goal of creating a screening strategy for further clinical application.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Atrofia Muscular/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Animales , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Humanos , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Relación Estructura-Actividad , Pérdida de Peso/efectos de los fármacos
13.
Postgrad Med ; 122(3): 166-80, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20463426

RESUMEN

Cancer remains a leading cause of morbidity and mortality. Despite advances in understanding, detection, and treatment, it accounts for almost one-fourth of all deaths per year in Western countries. Prostate cancer is currently the most commonly diagnosed noncutaneous cancer in men in Europe and the United States, accounting for 15% of all cancers in men. As life expectancy of individuals increases, it is expected that there will also be an increase in the incidence and mortality of prostate cancer. Prostate cancer may be inoperable at initial presentation, unresponsive to chemotherapy and radiotherapy, or recur following appropriate treatment. At the time of presentation, patients may already have metastases in their tissues. Preventing tumor recurrence requires systemic therapy; however, current modalities are limited by toxicity or lack of efficacy. For patients with such metastatic cancers, the development of alternative therapies is essential. Gene therapy is a realistic prospect for the treatment of prostate and other cancers, and involves the delivery of genetic information to the patient to facilitate the production of therapeutic proteins. Therapeutics can act directly (eg, by inducing tumor cells to produce cytotoxic agents) or indirectly by upregulating the immune system to efficiently target tumor cells or by destroying the tumor's vasculature. However, technological difficulties must be addressed before an efficient and safe gene medicine is achieved (primarily by developing a means of delivering genes to the target cells or tissue safely and efficiently). A wealth of research has been carried out over the past 20 years, involving various strategies for the treatment of prostate cancer at preclinical and clinical trial levels. The therapeutic efficacy observed with many of these approaches in patients indicates that these treatment modalities will serve as an important component of urological malignancy treatment in the clinic, either in isolation or in combination with current approaches.


Asunto(s)
Terapia Genética , Neoplasias de la Próstata/terapia , Animales , Vectores Genéticos , Humanos , Inmunoterapia , Masculino , Ratones
14.
Thromb Res ; 106(2): 149-56, 2002 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-12182915

RESUMEN

The purpose of this study was to characterize the responses of human and non-human primate (Macaca mulatta) platelets to anti-heparin-platelet factor 4 (AHPF4) antibodies. Due to the variations observed in the functionality and immunoglobulin isotypes in patients with heparin-induced thrombocytopenia (HIT), we used highly characterized human AHPF4 antibodies to study platelet activation responses. Using ELISA and 14C-serotonin release assay (SRA) systems, three patients' plasmapheresis fluid with similar responses to these assays were pooled. This pool was then used to study the platelet activation responses of human and primate platelets in the HIT platelet aggregation assay, a flow cytometry assay, and a variation of the aggregation assay in which glycoprotein IIb/IIIa inhibitors were supplemented. In the plasmapheresis fluid from three patients, the most significant AHPF4 immunoglobulin isotype present (based on optical density readings) was IgG, with less IgM (p < 0.001) and IgA (p < 0.001). The SRA yielded equivalent platelet activation results in all three patients. Using this pool in the platelet aggregation assay, without any heparin present, there was less percent aggregation (p < 0.001) with human platelets (11.8 +/- 2.35, n = 5) compared to the primate platelets (54.3 +/- 10.2, n = 9). In presence of 0.4 U/ml heparin, both platelet types had similar percent aggregations (p > 0.05). Three glycoprotein IIb/IIIa receptor inhibitors were used to evaluate the similarities in platelet activation. Eptifibatide was found to be a strong inhibitor of both species' platelet types at concentrations greater than 0.01 microg/ml. This was not the case with tirofiban which inhibited both human and monkey platelets at concentrations greater than 0.025 microg/ml. Abciximab inhibited aggregation at concentrations greater than 6.25 microg/ml. These data indicate that phylogenetic similarities in platelets of humans and primates may be used to further characterize the pathophysiology of HIT syndrome.


Asunto(s)
Autoanticuerpos/farmacología , Plaquetas/efectos de los fármacos , Heparina/toxicidad , Modelos Animales , Activación Plaquetaria/efectos de los fármacos , Factor Plaquetario 4/inmunología , Púrpura Trombocitopénica Idiopática/inducido químicamente , Abciximab , Animales , Anticuerpos Monoclonales/farmacología , Especificidad de Anticuerpos , Autoanticuerpos/inmunología , Plaquetas/metabolismo , Eptifibatida , Heparina/inmunología , Heparina/metabolismo , Humanos , Fragmentos Fab de Inmunoglobulinas/farmacología , Macaca mulatta , Péptidos/farmacología , Filogenia , Plasmaféresis , Inhibidores de Agregación Plaquetaria/farmacología , Factor Plaquetario 4/metabolismo , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Púrpura Trombocitopénica Idiopática/sangre , Púrpura Trombocitopénica Idiopática/inmunología , Púrpura Trombocitopénica Idiopática/terapia , Serotonina/metabolismo , Especificidad de la Especie , Tirofibán , Tirosina/análogos & derivados , Tirosina/farmacología
15.
Thromb Res ; 105(5): 401-5, 2002 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-12062541

RESUMEN

Heparin-induced thrombocytopenia (HIT) is an immune-mediated syndrome that can lead to limb- and life-threatening thrombosis. Argatroban, a small synthetic molecule (Argatroban; GlaxoSmithKline, Philadelphia, PA), and lepirudin, a protein of non-human origin (Refludan; Aventis, Bridgewater, NJ), are direct thrombin inhibitors that have been used successfully for anticoagulant therapy in HIT patients. It has been reported that between 44-74% of lepirudin-treated HIT patients develop drug-specific antibodies that either enhance or suppress the anticoagulant activity of lepirudin. By contrast, there have been no reported patient experiences suggestive of unexpected loss or enhancement of argatroban's anticoagulant effect in clinical trials, including those in HIT patients, or in postmarketing safety surveillance of over 4,800 patients treated in Japan. To confirm the lack of antibodies in argatroban-treated patients with HIT, we examined plasma for anticoagulant-altering activity and reviewed dosing patterns of re-exposed patients. Paired, pre-therapy and post-therapy (> or =7 days) plasma pools exhibited comparable in vitro anticoagulant responses (aPTT and antithrombin activity) to argatroban supplementation. Argatroban at 5 microg/mL similarly prolonged aPTTs of normal plasma pretreated with IgG isolated from pre-therapy versus post-therapy plasma (P>0.6). In trials, mean argatroban doses during initial therapy versus re-exposure were not different among individuals anticoagulated for the treatment or prophylaxis of thrombosis (P=0.60) or during percutaneous coronary interventions (P=0.79), with no discernable pattern of suppression or enhancement of argatroban anticoagulation. Consistent with the lack of reported patient experiences suggestive of unexpected loss or enhancement of argatroban's anticoagulant effect across clinical trials and post-marketing safety surveillance, these data support the lack of anti-argatroban antibodies that affect drug activity in argatroban-treated HIT patients.


Asunto(s)
Anticuerpos/sangre , Anticoagulantes/administración & dosificación , Heparina/efectos adversos , Ácidos Pipecólicos/administración & dosificación , Trombocitopenia/inducido químicamente , Anticoagulantes/inmunología , Anticoagulantes/farmacología , Arginina/análogos & derivados , Relación Dosis-Respuesta a Droga , Heparina/inmunología , Humanos , Tiempo de Tromboplastina Parcial , Ácidos Pipecólicos/inmunología , Ácidos Pipecólicos/farmacología , Sulfonamidas , Trombocitopenia/inmunología , Trombosis/tratamiento farmacológico , Trombosis/prevención & control
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