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1.
Curr Diabetes Rev ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747222

RESUMEN

The link between Type 2 Diabetes (T2DM) and Parkinson's Disease (PD) dates back to the early 1960s, and ongoing research is exploring this association. PD is linked to dysregulation of dopaminergic pathways, neuroinflammation, decreased PPAR-γ coactivator 1-α, increased phosphoprotein enriched in diabetes, and accelerated α-Syn amyloid fibril production caused by T2DM. This study aims to comprehensively evaluate the T2DM-PD association and risk factors for PD in T2DM individuals. The study reviews existing literature using reputable sources like Scopus, ScienceDirect, and PubMed, revealing a significant association between T2DM and worsened PD symptoms. Genetic profiles of T2DM-PD individuals show similarities, and potential risk factors include insulin-resistance and dysbiosis of the gut-brain microbiome. Anti-diabetic drugs exhibit neuroprotective effects in PD, and nanoscale delivery systems like exosomes, micelles, and liposomes show promise in enhancing drug efficacy by crossing the Blood-Brain Barrier (BBB). Brain targeting for PD uses exosomes, micelles, liposomes, dendrimers, solid lipid nanoparticles, nano-sized polymers, and niosomes to improve medication and gene therapy efficacy. Surface modification of nanocarriers with bioactive compounds (such as angiopep, lactoferrin, and OX26) enhances α-Syn conjugation and BBB permeability. Natural exosomes, though limited, hold potential for investigating DM-PD pathways in clinical research. The study delves into the underlying mechanisms of T2DM and PD and explores current therapeutic approaches in the field of nano-based targeted drug delivery. Emphasis is placed on resolved and ongoing issues in understanding and managing both conditions.

2.
Biotechnol Prog ; : e3448, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477405

RESUMEN

Host cell proteins (HCPs) are process-related impurities in a therapeutic protein expressed using cell culture technology. This review presents biopharmaceutical industry trends in terms of both HCPs in the bioprocessing of monoclonal antibodies (mAbs) and the capabilities for HCP clearance by downstream unit operations. A comprehensive assessment of currently implemented and emerging technologies in the manufacturing processes with extensive references was performed. Meta-analyses of published downstream data were conducted to identify trends. Improved analytical methods and understanding of "high-risk" HCPs lead to more robust manufacturing processes and higher-quality therapeutics. The trend of higher cell density cultures leads to both higher mAb expression and higher HCP levels. However, HCP levels can be significantly reduced with improvements in operations, resulting in similar concentrations of approx. 10 ppm HCPs. There are no differences in the performance of HCP clearance between recent enhanced downstream operations and traditional batch processing. This review includes best practices for developing improved processes.

3.
Recent Adv Food Nutr Agric ; 15(2): 138-162, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38284698

RESUMEN

Vegetables and fruits are highly perishable agricultural commodities cultivated all over the world. However, inadequate handling practices have led to significant postharvest losses of these agricultural commodities, as well as the wastage of valuable resources, such as time and money. Hence, it can be observed that cultivators often experience significant financial setbacks as a result of inadequate comprehension regarding the nature and origins of these losses, insufficient preservation practices, and ineffective approaches to transportation and marketing. In addition, the utilization of suitable chemical agents during both the pre- and postharvest phases has the potential to prolong the shelf life of agricultural products. This preservation technique safeguards vegetables and fruits from pathogenic organisms and other forms of environmental harm, thereby enabling their availability for an extended duration. Therefore, this review proposes a methodology for managing fruits and vegetables postharvest to minimize losses and optimize returns.


Asunto(s)
Conservación de Alimentos , Frutas , Verduras , Frutas/microbiología , Conservación de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Humanos , Manipulación de Alimentos/métodos
4.
Dalton Trans ; 51(45): 17263-17276, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36317406

RESUMEN

In recent years, Ru(II) complexes have gained high importance in medicinal chemistry due to their significant anti-cancer activities, which are directly related to their DNA binding ability. In this report, the chemistry and cytotoxicity of two new Ru(II) complexes containing imidazole pyridine (Ru-1) and imidazole quinoline (Ru-2) have been studied. The prepared compounds were characterized using infrared (IR), nuclear magnetic resonance (NMR), mass spectrometry (MS), isothermal titration calorimetry (ITC), UV-Vis, and fluorescence spectral techniques. The structural analyses show that the Ru(II) complexes exhibit a 'piano stool' coordination geometry and they are composed of one bound arene, two sigma bonded benzil nitrogen atoms, and labile chlorine linked to Ru(II). The photo-physical properties of these complexes were examined, and they exhibit absorption peaks at 260 nm and 380 nm, which are due to the involvement of intra-ligand charge transitions (ILCT) and metal-to-ligand charge transitions (MLCT), respectively. The binding process of the Ru(II) complexes with DNA and BSA is non-covalent in nature and the binding constants of Ru-1 and Ru-2 complexes with DNA and BSA were found to be 1 × 105 M-1 and 1 × 103 M-1, respectively. In the presence of the Ru(II) complexes, ethidium bromide (EtBr) is competitively displaced from DNA by intercalation of the Ru(II) complexes in DNA and it is well corroborated by viscosity and in silico studies. Both the ligands and Ru(II) complexes were carefully investigated in vitro for cytotoxicity against HeLa, MCF-7, and MDA-MB-231 cells. Surprisingly, both Ru(II) complexes exhibit superior cytotoxicity to cisplatin with a low LD50 value against the examined cancer cells. Besides, an insignificant effect on HEK normal cells (LD50 > 140 µM) was observed.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Quinolinas , Rutenio , Humanos , Rutenio/química , Ligandos , Complejos de Coordinación/química , Estructura Molecular , Antineoplásicos/farmacología , Antineoplásicos/química , ADN/química , Imidazoles/farmacología , Quinolinas/farmacología , Piridinas/farmacología , Línea Celular Tumoral
5.
RSC Adv ; 12(24): 15385-15406, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35693235

RESUMEN

The nitrogen-bearing heterocycle pyridine in its several analogous forms occupies an important position as a precious source of clinically useful agents in the field of medicinal chemistry research. This privileged scaffold has been consistently incorporated in a diverse range of drug candidates approved by the FDA (Food and Drug Administration). This moiety has attracted increasing attention from several disease states owing to its ease of parallelization and testing potential pertaining to the chemical space. In the next few years, a larger share of novel pyridine-based drug candidates is expected. This review unifies the current advances in novel pyridine-based molecular frameworks and their unique clinical relevance as reported over the last two decades. It highlights an inclination to the use of pyridine-based molecules in drug crafting and the subsequent emergence of several potent and eligible candidates against a range of diversified diseases.

6.
Anticancer Agents Med Chem ; 22(15): 2684-2707, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35362388

RESUMEN

Metal based therapy is no new in biomedical research. In early days, the biggest limitation was the inequality among therapeutical and toxicological dosages. Ever since, Barnett Rosenberg discovered cisplatin, a new era has begun to treat cancer with metal complexes. Platinum complexes such as oxaliplatin, cisplatin, and carboplatin, seem to be the foundation of metal/s-based components to challenge malignancies. With advancement in the biomolemoecular mechanism, researchers have started developing non-classical platinum-based complexes, where a different mechanistic approach of the complexes is observed towards the biomolecular target. Till date, larger numbers of metal/s-based complexes were synthesized by overhauling the present structures chemically by substituting the ligand or preparing the whole novel component with improved cytotoxic and safety profiles. Howsoever, due to elevated accentuation upon the therapeutic importance of metal/s-based components, a couple of those agents are at present in clinical trials and several other are in anticipating regulatory endorsement to enter the trial. This literature highlights the detailed heterometallic multinuclear components, primarily focusing on platinum, ruthenium, gold and remarks on possible stability, synergism, mechanistic studies and structure activity relationships.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Neoplasias , Rutenio , Antineoplásicos/química , Cisplatino/uso terapéutico , Complejos de Coordinación/química , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Platino (Metal)/química , Rutenio/química
7.
Mini Rev Med Chem ; 21(9): 1096-1112, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33238872

RESUMEN

Isatin is an endogenous and a significant category of fused heterocyclic components and has widely been a part of several potential biologically useful synthetics. Since its discovery, tons of research work has been conducted with respect to the synthesis, chemical properties, and biological and industrial applications. It contains an indole nucleus having both lactam and keto moiety, which, while being a part of a molecular framework, exerted several biological effects, viz.; anti-microbial, anti-tubercular, anticonvulsant, anti-cancer, etc. Isatin derivatives are synthetically significant substrates, which can be utilized for the synthesis of huge diversified chemical entities of which few members emerged as drugs. The reason for this review is to provide extensive information pertaining to the chemistry and its significance in altering several pathological states of isatin and its derivatives. A Structure-Activity Relationship study thus developed through a gamut of scientific information indicates the importance of mostly electron-withdrawing groups, halogens, nitro, alkoxy, and, to a minor extent, groups with positive inductive effects, such as methyl at position 1, 5, 6 and 7 of isatin in alleviating several clinical conditions. It is also observed from the survey that the presence of two oxo groups at positions 2 and 3 sometimes becomes insignificant as a fusion with a heterocycle at these positions resulted in a biologically relevant compound.


Asunto(s)
Antiinfecciosos/farmacología , Anticonvulsivantes/farmacología , Antineoplásicos/farmacología , Antituberculosos/farmacología , Isatina/farmacología , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Anticonvulsivantes/síntesis química , Anticonvulsivantes/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Antituberculosos/síntesis química , Antituberculosos/química , Biodiversidad , Humanos , Isatina/análogos & derivados , Isatina/química , Estructura Molecular
8.
Reprod Biomed Online ; 38(2): 159-168, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30598377

RESUMEN

RESEARCH QUESTION: Circulating soluble LH-HCG receptor (sLHCGR) is a first-trimester marker for screening pregnancy pathologies and predicts premature or multiple births before fertility treatment. Oestradiol per oocyte at ovulation induction predicts IVF treatment outcomes. We asked whether sLHCGR levels are stable during fertility treatment and whether, alone or with oestradiol, they could improve prediction of fertility treatment outcomes. DESIGN: Serum sLHCGR, anti-Müllerian hormone [AMH] and oestradiol were measured in patients undergoing IVF. Antral follicle count before ovarian stimulation and oocyte yield were used to establish sLHCGR- oocyte ratio (SOR), sLHCGR- antral follicle ratio (SAR), oestradiol at trigger per oocyte (oestradiol-oocyte ratio [EOR]) and oestradiol at trigger per antral follicle (oestradiol-antral follicle ratio [EAR]). RESULTS: The relatively stable sLHCGR was negatively related to AMH when oocyte yield was high. The sLHCGR levels were proportional (r = 0.49) to oestradiol at early cycle (day-3). Pregnancy and live birth were highest at low sLHCGR (≤1.0 pmol/ml) and SOR (≤ 0.1 pmol/ml/oocyte). A total of 86-89% of live births in IVF treatment were within the cut-off parameters of SAR and SOR (0.5 pmol/ml) and EAR and EOR (380 pg/ml). For failed pregnancy, age, SOR and EOR together had positive and negative predictive values of 0.841 and 0.703, respectively. CONCLUSIONS: sLHCGR levels are negatively related to AMH when oocyte yield is high. High early cycle sLHCGR is associated with elevated day-3 oestradiol. Low sLHCGR and SOR are indicators of increased clinical pregnancy and live birth rates. Patient age and SOR, combined with EOR, might improve prediction of IVF treatment outcomes.


Asunto(s)
Estradiol/sangre , Fertilización In Vitro , Nacimiento Vivo , Índice de Embarazo , Receptores de HL/sangre , Adulto , Hormona Antimülleriana/sangre , Femenino , Humanos , Folículo Ovárico , Inducción de la Ovulación , Embarazo , Resultado del Embarazo
9.
Mini Rev Med Chem ; 19(2): 88-97, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29692250

RESUMEN

Diabetes mellitus is an emerging predator and affecting around 422 million adults worldwide. Higher levels of circulating insulin and increased pressure on the pancreas to produce insulin have been inferred as possible etiology for diabetes leading to a higher risk of pancreatic cancer. Out of several drug targets in hypoglycemic discovery, Dipeptidyl peptidase-IV (DPP-IV) has been considered an emerging target. It is a protease enzyme which inactivates incretin hormones i.e., Glucagonlike peptide 1 (GLP-1) and glucose-dependent insulin tropic polypeptide (GIP). Inhibition of DPP-4 results in the longer action of GLP-1 and GIP, therefore, DPP-4 inhibitors play an important role in maintaining glucose homeostasis. In comparison to early oral hypoglycemic, DPP-IV inhibitors are well tolerated and provide a better glycemic control over a longer period. These enzymes are expressed in a dimeric form on the surface of different cells such as prostate, liver and small intestinal epithelium cells. Disruption of the local signaling environment is an emerging factor in cancer development. Till date, not even a single DPP-IV inhibitor as anticancer has been developed. This review focuses on various features of the enzyme and their suitable inhibitors for target disease.


Asunto(s)
Antineoplásicos/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Dipeptidil Peptidasa 4/metabolismo , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Hipoglucemiantes/uso terapéutico , Neoplasias/tratamiento farmacológico , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Diabetes Mellitus/metabolismo , Dipeptidil Peptidasa 4/química , Inhibidores de la Dipeptidil-Peptidasa IV/química , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Modelos Moleculares , Terapia Molecular Dirigida/métodos , Neoplasias/metabolismo , Transducción de Señal/efectos de los fármacos
10.
Hum Fertil (Camb) ; 20(4): 279-284, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27900886

RESUMEN

The luteinizing hormone (LH) and pregnancy hormone, human chorionic gonadotrophin (hCG), share a common receptor: LH/hCG-R or LHCGR. In this prospective study involving 290 patients undergoing in vitro fertilization (IVF) and embryo transfer, we have examined whether pretreatment circulating LHCGR (sLHCGR) influences the course of pregnancy and perinatal outcome after embryo transfer. The blood samples were collected before the fertility treatment began and sLHCGR concentrations were measured using an enzyme-linked immunosorbent assay (ELISA) test. We demonstrate that extreme pretreatment sLHCGR concentrations (low & high) were linked to abnormal birth weights for singleton births, while very low concentrations of sLHCGR were associated with premature delivery (≤34 weeks) of singletons and multiple births following transfer of ≥2 embryos.


Asunto(s)
Progenie de Nacimiento Múltiple , Resultado del Embarazo , Nacimiento Prematuro/sangre , Receptores de HL/sangre , Transferencia de Embrión , Femenino , Fertilización In Vitro , Humanos , Recién Nacido , Embarazo , Embarazo Múltiple , Estudios Prospectivos
11.
Fetal Diagn Ther ; 38(2): 94-102, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25676660

RESUMEN

OBJECTIVE: To explore the value of circulating luteinizing human chorionic gonadotropin receptor (LHCGR) forms for the prediction of preeclampsia (PE) in the first trimester of pregnancy. METHODS: Case-control study, based on a cohort of 5,759 pregnancies, including 20 early PE, 20 late PE, and 300 controls. We recorded/measured maternal characteristics, mean arterial pressure (MAP), uterine artery (UtA) Doppler, placental growth factor (PlGF), soluble Fms-like tyrosine kinase-1 (sFtl-1), and LHCGR forms (hCG-LHCGR and soluble LHCGR), and their independent predictive values were analyzed by logistic regression. RESULTS: For early PE, the model included black ethnicity, chronic hypertension, previous PE, MAP, UtA Doppler, PlGF, sFlt-1, and LHCGR forms, achieving detection rates (DR) of 83% at 10% of false-positive rates (FPR) [AUC: 0.961 (95% CI: 0.921-1)]. For late PE, the model included body mass index, previous PE, UtA Doppler, PlGF, sFlt-1, and LHCGR forms, with DR of 75% at 10% of FPR [AUC: 0.923 (95% CI: 0.871-0.976)]. In both early and late PE, LHCGR forms improved DR by 6-15%. CONCLUSIONS: LHCGR forms improved the prediction for early and late PE. These results should be confirmed in larger prospective studies.


Asunto(s)
Preeclampsia/sangre , Preeclampsia/diagnóstico por imagen , Primer Trimestre del Embarazo/sangre , Receptores de HL/sangre , Adulto , Biomarcadores/sangre , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Ultrasonografía
12.
Pharmacogn Mag ; 10(Suppl 2): S288-93, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24991105

RESUMEN

BACKGROUND: Garlic (Allium sativum L.) has been accepted universally to be applied in food, spice and traditional medicine. The medicinal and other beneficial properties of garlic are attributed to organosulfur compounds. OBJECTIVE: As of today no simultaneous analysis has been performed; hence the transformation of allicin to its degraded products during cultivation and storage is open into doubt. MATERIALS AND METHODS: In our present work, we have tried to develop a sensitive and reproducible analytical method to measure allicin by high performance liquid chromatography-ultraviolet analysis with effect of post-acoustic waves and microwave radiation on fresh garlic cloves. RESULTS: The process revealed the effect of different radiation techniques on fresh garlic retains the principle component, allicin in its pure form and generated higher yield than the conventional way of extraction. CONCLUSION: Therefore, materializing these techniques in the pharmaceutical industry will definitely be proved beneficial in term of time as well as money. Most interestingly, the methods ruled out possibilities of degradation of organosulfur compounds as well.

13.
BMC Pregnancy Childbirth ; 14: 197, 2014 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-24906955

RESUMEN

BACKGROUND: Previous studies showed that soluble LHCGR/hCG-sLHCGR concentrations in serum or plasma combined with PAPP-A and free ßhCG significantly increased the sensitivity of Down's syndrome screen at early pregnancy without altering the false positive rate. The goal of the present study was to further examine the role of sLHCGR forms as combinatorial markers and to investigate whether sLHCGR could serve as an independent biomarker for Down's syndrome in first trimester pregnancy screens. METHODS: The PAPP-A, free ßhCG, and hCG-sLHCGR concentrations together with nuchal translucency (NT) were measured in 40 Down's and 300 control pregnancies. The sLHCGR concentration was analysed in 40 Down's and 206 control pregnancies. RESULTS: The hCG-LHCGR in combination with PAPP-A and free ßhCG increased the detection rate (DR) by 35% without altering the false positive rate (FPR). The sLHCGR: hCG-sLHCGR ratio alone detected 80% of Down's pregnancies in first trimester screening, with a false positive rate of 0.5%. CONCLUSIONS: While measurement of sLHCGR forms in combination with PAPP-A and free ßhCG significantly increases the detection rate of Down's syndrome at first trimester, the ratio of sLHCGR: hCG-sLHCGR acts as an independent marker with a detection rate that is significantly higher than the existing biochemical markers individually for prenatal first trimester screening of Down's syndrome.


Asunto(s)
Gonadotropina Coriónica Humana de Subunidad beta/sangre , Síndrome de Down/diagnóstico , Diagnóstico Prenatal/métodos , Receptores de HL/sangre , Área Bajo la Curva , Biomarcadores/sangre , Estudios de Casos y Controles , Reacciones Falso Positivas , Femenino , Humanos , Medida de Translucencia Nucal , Valor Predictivo de las Pruebas , Embarazo , Primer Trimestre del Embarazo/sangre , Proteína Plasmática A Asociada al Embarazo/metabolismo , Curva ROC , Estudios Retrospectivos
14.
Reprod Biol Endocrinol ; 10: 113, 2012 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-23245345

RESUMEN

BACKGROUND: Soluble LH/hCG receptor (sLHCGR) released from placental explants and transfected cells can be detected in sera from pregnant women. To determine whether sLHCGR has diagnostic potential, quantitative ELISAs were developed and tested to examine the correlation between pregnancy outcome and levels of serum sLHCGR and hCG-sLHCGR complex. METHODS: Anti-LHCGR poly- and monoclonal antibodies recognizing defined LHCGR epitopes, commerical anti-hCGbeta antibody, together with recombinant LHCGR and yoked hCGbeta-LHCGR standard calibrators were used to develop two ELISAs. These assays were employed to quantify serum sLHCGR and hCG-sLHCGR at first trimester human pregnancy. RESULTS: Two ELISAs were developed and validated. Unlike any known biomarker, sLHCGR and hCG-sLHCGR are unique because Down's syndrome (DS), preeclampsia and preterm delivery are linked to both low (less than or equal to 5 pmol/mL), and high (equal to or greater than 170 pmol/mL) concentrations. At these cut-off values, serum hCG-sLHCGR together with PAPP-A detected additional DS pregnancies (21%) which were negative by free hCGbeta plus PAPP-A screening procedure. Therefore, sLHCGR/hCG-sLHCGR has an additive effect on the current primary biochemical screening of aneuploid pregnancies. More than 88% of pregnancies destined to end in fetal demise (stillbirth) exhibited very low serum hCG-sLHCGR(less than or equal to 5 pmol/mL) compared to controls (median 16.15 pmol/mL, n = 390). The frequency of high hCG-sLHCGR concentrations (equal to or greater than 170 pmol/mL) in pathological pregnancies was at least 3-6-fold higher than that of the control, suggesting possible modulation of the thyrotropic effect of hCG by sLHCGR. CONCLUSIONS: Serum sLHCGR/hCG-sLHCGR together with PAPP-A, have significant potential as first trimester screening markers for predicting pathological outcomes in pregnancy.


Asunto(s)
Síndrome de Down/diagnóstico , Preeclampsia/diagnóstico , Primer Trimestre del Embarazo/sangre , Nacimiento Prematuro/diagnóstico , Receptores de HL/sangre , Adulto , Anticuerpos Monoclonales , Gonadotropina Coriónica Humana de Subunidad beta/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Enfermedades Fetales/diagnóstico , Humanos , Embarazo , Resultado del Embarazo , Proteína Plasmática A Asociada al Embarazo , Diagnóstico Prenatal/métodos , Estudios Prospectivos , Receptores de HL/inmunología , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Mortinato
15.
Reprod Biol Endocrinol ; 9: 161, 2011 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-22195987

RESUMEN

BACKGROUND: Successful pregnancy via in vitro fertilization (IVF) depends on the recovery of an adequate number of healthy oocytes and on blastocyst implantation following uterine transfer. Two hormones, LH and hCG, utilize a common LH/hCG receptor (LHCGR), variations in which have profound implications in human reproduction. Soluble LHCGR (sLHCGR) is released from experimental cell lines and placental explants and it can be detected in the follicular fluid and serum. METHODS: To evaluate the impact of circulating soluble LHCGR (sLHCGR) in fertility treatment, we measured sLHCGR and LH-sLHCGR complex in serum from women seeking IVF using specifically developed quantitative enzyme-linked immunosorbent assays (ELISA). Following an IVF cycle of treatment, patients were grouped according to oocyte yield into low (lower than or equal to 7 oocytes), intermediate (8-14 oocytes) and high (greater than or equal to 15 oocytes) responders and pregnancy outcome noted. RESULTS: Pre-treatment sLHCGR identified many women at risk of ovarian hyperstimulation. Low levels of sLHCGR were associated with pregnancy in both high and low responders but sLHCGR did not significantly affect the treatment outcome of intermediate responders. Low responders who failed to become pregnant had high levels of circulating sLHCGR bound to LH (LH-sLHCGR). CONCLUSIONS: Pre-treatment measurement of sLHCGR could be used to tailor individual fertility treatment programs and improve outcomes by avoiding ovarian hyperstimulation and poor embryo implantation.


Asunto(s)
Síndrome de Hiperestimulación Ovárica/sangre , Receptores de HL/sangre , Factores de Edad , Hormona Antimülleriana/sangre , Implantación del Embrión , Ensayo de Inmunoadsorción Enzimática , Femenino , Fertilización In Vitro , Humanos , Hormona Luteinizante/sangre , Inducción de la Ovulación , Embarazo , Resultado del Embarazo , Estudios Prospectivos , Factores de Riesgo
16.
Reprod Biol Endocrinol ; 9: 64, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21575145

RESUMEN

Placental hCG and pitutary LH transduce signals in target tissues through a common receptor (LHCGR). We demonstrate that recombinant LHCGR proteins which include the hormone-binding domain are secreted from transfected cells and that natural LHCGR is also secreted from human placental explants. LHCGR recombinant proteins representing varying lengths of the N-terminal extracellular domain were expressed in Chinese Hamster Ovary cells in suspension culture. Secretion was minimal up to 72h but by 96h 24-37% of the LHCGR had been released into the culture medium. The secreted proteins were folded and sensitive to glycosidases suggesting N-linked glycosylation. Secretion was independent of recombinant size and was mediated via structurally defined membrane vesicles (50-150nm). Similarly cultured human early pregnancy placental explants also released LHCGR via microvesicles. These studies provide the first experimental evidence of the possible mechanistic basis of the secretion of LHCGR.


Asunto(s)
Placenta/metabolismo , Receptores de HL/metabolismo , Vesículas Secretoras/metabolismo , Animales , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Femenino , Humanos , Técnicas de Cultivo de Órganos , Embarazo , Receptores de HL/genética , Solubilidad , Transfección
17.
J Theor Biol ; 273(1): 188-96, 2011 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-21194534

RESUMEN

The jasmonate (JA) signaling pathway in plants is activated as defense response to a number of stresses like attacks by pests or pathogens and wounding by animals. Some recent experiments provide significant new knowledge on the molecular detail and connectivity of the pathway. The pathway has two major components in the form of feedback loops, one negative and the other positive. We construct a minimal mathematical model, incorporating the feedback loops, to study the dynamics of the JA signaling pathway. The model exhibits transient gene expression activity in the form of JA pulses in agreement with experimental observations. The dependence of the pulse amplitude, duration and peak time on the key parameters of the model is determined computationally. The deterministic and stochastic aspects of the pathway dynamics are investigated using both the full mathematical model and a reduced version of it. We also compare the mechanism of pulse formation with the known mechanisms of pulse generation in some bacterial and viral systems.


Asunto(s)
Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Transducción de Señal , Modelos Biológicos , Plantas/metabolismo , Procesos Estocásticos , Factores de Tiempo
18.
Reprod Biol Endocrinol ; 7: 4, 2009 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-19146669

RESUMEN

The concept that oxidative stress contributes to the development of human preeclampsia has never been tested in genetically-defined animal models. Homozygous deletion of catechol-O-methyl transferase (Comt-/-) in pregnant mice leads to human preeclampsia-like symptoms (high blood pressure, albuminurea and preterm birth) resulting from extensive vasculo-endothelial pathology, primarily at the utero-fetal interface where maternal cardiac output is dramatically increased during pregnancy. Comt converts estradiol to 2-methoxyestradiol 2 (2ME2) which counters angiogenesis by depleting hypoxia inducible factor-1 alpha (HIF-1 alpha) at late pregnancy. We propose that in wild type (Comt++) pregnant mice, 2ME2 destabilizes HIF-1 alpha by inhibiting mitochondrial superoxide dismutase (MnSOD). Thus, 2ME2 acts as a pro-oxidant, disrupting redox-regulated signaling which blocks angiogenesis in wild type (WT) animals in physiological pregnancy. Further, we suggest that a lack of this inhibition under normoxic conditions in mutant animals (Comt-/-) stabilises HIF-1 alpha by inactivating prolyl hydroxlases (PHD). We predict that a lack of inhibition of MnSOD, leading to persistent accumulation of HIF-1 alpha, would trigger inflammatory infiltration and endothelial damage in mutant animals. Critical tests of this hypothesis would be to recreate preeclampsia symptoms by inducing oxidative stress in WT animals or to ameliorate by treating mutant mice with Mn-SOD-catalase mimetics or activators of PHD.


Asunto(s)
Modelos Animales de Enfermedad , Ratones , Preeclampsia/metabolismo , Transducción de Señal , 2-Metoxiestradiol , Animales , Catecol O-Metiltransferasa/genética , Estradiol/análogos & derivados , Estradiol/metabolismo , Femenino , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Proteínas Mitocondriales/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Preeclampsia/genética , Embarazo , Superóxido Dismutasa/metabolismo
19.
Phys Biol ; 5(4): 046008, 2008 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-19098361

RESUMEN

We study the functional characteristics of a two-gene motif consisting of a double positive feedback loop and an autoregulatory negative feedback loop. The motif appears in the gene regulatory network controlling the functional activity of pancreatic beta-cells. The model exhibits bistability and hysteresis in appropriate parameter regions. The two stable steady states correspond to low (OFF state) and high (ON state) protein levels, respectively. Using a deterministic approach, we show that the region of bistability increases in extent when the copy number of one of the genes is reduced from 2 to 1. The negative feedback loop has the effect of reducing the size of the bistable region. Loss of a gene copy, brought about by mutations, hampers the normal functioning of the beta-cells giving rise to the genetic disorder, maturity-onset diabetes of the young (MODY). The diabetic phenotype makes its appearance when a sizable fraction of the beta-cells is in the OFF state. Using stochastic simulation techniques we show that, on reduction of the gene copy number, there is a transition from the monostable ON to the ON state in the bistable region of the parameter space. Fluctuations in the protein levels, arising due to the stochastic nature of gene expression, can give rise to transitions between the ON and OFF states. We show that as the strength of autorepression increases, the ON --> OFF state transitions become less probable whereas the reverse transitions are more probable. The implications of the results in the context of the occurrence of MODY are pointed out.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Regulación hacia Abajo/genética , Retroalimentación Fisiológica/genética , Redes Reguladoras de Genes/genética , Modelos Genéticos , Simulación por Computador , Factor Nuclear 4 del Hepatocito/biosíntesis , Factor Nuclear 4 del Hepatocito/genética , Fenotipo , Procesos Estocásticos
20.
Artículo en Inglés | MEDLINE | ID: mdl-19008160

RESUMEN

The antibody fragments generated from hyperimmune equine IgG is widely used as anti-snake venom, anti-scorpion venom, anti-diphtheria, anti-tetanus, anti-gangrene and anti-rabies agents. Antibody fragments, F(ab)(2), because of their specificity and absence of undesired reactivity are preferred over complete IgG. This paper discusses a novel purification technique for chromatographic purification of anti-rabies immunoglobulin G (IgG) fragment F(ab)(2) from horse serum. F(ab)(2) was purified by two successive chromatography steps using Cellufine A-200 and ProSep-vA Ultra media. The purified F(ab)(2) was characterized using biochemical and biophysical methods and shown to be pure and homogeneous. The purified F(ab)(2) was reactive to rabies antigen in immuno-electrophoresis and diffusion tests. The purified F(ab)(2) was biologically functional and was found to show a potency of 1500 IU ml(-1). Comparative analysis of the purity with commercially available F(ab)(2) by HPLC analysis and SDS-PAGE indicated that the present product is better in purity. To our knowledge, this is the first report providing evidence on purification of equine antibody fragment using controlled pore glass based protein A chromatography media.


Asunto(s)
Cromatografía de Afinidad/métodos , Cromatografía por Intercambio Iónico/métodos , Caballos/sangre , Fragmentos Fab de Inmunoglobulinas/aislamiento & purificación , Inmunoglobulina G/aislamiento & purificación , Animales , Vacunas Antirrábicas/inmunología , Proteína Estafilocócica A/inmunología
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