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The paper describes an investigation of phase decomposition of apatite lattice doped with rare earth ions (cerium, samarium, and holmium) at temperatures ranging from 25 to 1200 ºC. The rare-earth ion-doped apatite minerals were synthesized using sol-gel method. In situ high-temperature powder X-ray diffraction (XRD) was used to observe phase changes and the lattice parameters were analyzed to ascertain the crystallographic transformations. The expansion coefficient of the compounds was determined, and it was found that the c-axis was the most expandable due to relatively weak chemical bonds along the c-crystallographic axis. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to examine the decomposition properties of the materials. Due to rare earth ion doping, the produced materials had slightly variable decomposition behaviour. The cerium and samarium ions were present in multiple oxidation states (Ce3+, Ce4+, Sm3+, Sm2+), whereas only Ho3+ ions were observed. Rare earth ion substitution affects tri-calcium phosphate proportion during decomposition by regulating concentrations of vacancies. X-ray photoelectron spectroscopy (XPS) analysis indicated that cerium and samarium ion-doped apatite yielded only 25% tricalcium phosphate during decomposition. This finding advances our understanding of apatite structures, with implications for various high-temperature processes like calcination, sintering, hydrothermal processing, and plasma spraying.
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BACKGROUND & AIMS: Early-onset colorectal cancer (EOCRC) is a distinct clinical and molecular entity with poor survival outcomes compared with late-onset CRC. Although the incidence of EOCRC is rising, current CRC screening strategies have several limitations in diagnostic performance for EOCRC. In view of this clinical challenge, novel and robust biomarkers for detection of EOCRC are necessary. The aim of this study was to develop a circulating micro RNA (miRNA) signature for the diagnosis of patients with EOCRC. METHODS: A systematic discovery approach by analyzing a large, publicly available, noncoding RNA expression profiling dataset (GSE115513) was used. A panel of miRNAs was identified, which was subsequently validated in blood samples from patients with EOCRC in 2 independent cohorts (n = 149) compared with controls (n = 110) and pre/postoperative plasma specimens (n = 22) using quantitative reverse-transcription polymerase chain reaction assays. RESULTS: In the discovery phase, 4 miRNAs were found to be expressed in blood samples. A combination signature of these 4 miRNAs (miR-193a-5p, miR-210, miR-513a-5p, and miR-628-3p) yielded an area under the curve of 0.92 (95% confidence interval, 0.85-0.96) for identification of EOCRC in the training cohort. The miRNA panel performance was then confirmed in an independent validation cohort (area under the curve, 0.88; 95% confidence interval, 0.82-0.93). Moreover, the miRNA panel robustly identified patients with early-stage EOCRC (P < .001). The decreased expression of miRNAs in postsurgery plasma specimens indicated their tumor specificity. CONCLUSIONS: Our novel miRNA signature for the diagnosis of EOCRC has the potential to identify patients with EOCRC with high accuracy for clinical application in the noninvasive diagnosis of EOCRC.
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MicroARN Circulante , Neoplasias Colorrectales , MicroARNs , Humanos , Biomarcadores de Tumor/genética , Curva ROC , MicroARNs/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Biopsia Líquida , Perfilación de la Expresión GénicaRESUMEN
BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) incidence is rising worldwide, and most patients present with an unresectable disease at initial diagnosis. Measurement of carbohydrate antigen 19-9 (CA19-9) levels lacks adequate sensitivity and specificity for early detection; hence, there is an unmet need to develop alternate molecular diagnostic biomarkers for PDAC. Emerging evidence suggests that tumor-derived exosomal cargo, particularly micro RNAs (miRNAs), offer an attractive platform for the development of cancer-specific biomarkers. Herein, genomewide profiling in blood specimens was performed to develop an exosome-based transcriptomic signature for noninvasive and early detection of PDAC. METHODS: Small RNA sequencing was undertaken in a cohort of 44 patients with an early-stage PDAC and 57 nondisease controls. Using machine-learning algorithms, a panel of cell-free (cf) and exosomal (exo) miRNAs were prioritized that discriminated patients with PDAC from control subjects. Subsequently, the performance of the biomarkers was trained and validated in independent cohorts (n = 191) using quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. RESULTS: The sequencing analysis initially identified a panel of 30 overexpressed miRNAs in PDAC. Subsequently using qRT-PCR assays, the panel was reduced to 13 markers (5 cf- and 8 exo-miRNAs), which successfully identified patients with all stages of PDAC (area under the curve [AUC] = 0.98 training cohort; AUC = 0.93 validation cohort); but more importantly, was equally robust for the identification of early-stage PDAC (stages I and II; AUC = 0.93). Furthermore, this transcriptomic signature successfully identified CA19-9 negative cases (<37 U/mL; AUC = 0.96), when analyzed in combination with CA19-9 levels, significantly improved the overall diagnostic accuracy (AUC = 0.99 vs AUC = 0.86 for CA19-9 alone). CONCLUSIONS: In this study, an exosome-based liquid biopsy signature for the noninvasive and robust detection of patients with PDAC was developed.
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Adenocarcinoma , Carcinoma Ductal Pancreático , Exosomas , MicroARNs , Neoplasias Pancreáticas , Humanos , Antígeno CA-19-9 , Exosomas/genética , Exosomas/patología , Transcriptoma , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Biomarcadores de Tumor/genética , Estudios de Cohortes , MicroARNs/genética , Carbohidratos , Neoplasias PancreáticasRESUMEN
Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, which is usually diagnosed at an advanced stage. The late disease diagnosis, the limited availability of effective therapeutic interventions and lack of robust diagnostic biomarkers, are some of the primary reasons for the dismal 5-year survival rates (â¼8%) in patients with PDAC. The pancreatic cancer develops through accumulation of a series of genomic and epigenomic alterations which lead to the transformation of normal pancreatic epithelium into an invasive carcinoma - a process that can take up to 15-20 years to develop, from the occurrence of first initiating mutational event. These facts highlight a unique window of opportunity for the earlier detection of PDAC, which could allow timely disease interception and improvement in the overall survival outcomes in patients suffering from this fatal malignancy. Non-coding RNAs (ncRNAs) have been recognized to play a central role in PDAC pathogenesis and are emerging as attractive candidates for biomarker development in various cancers, including PDAC. More specifically, the ncRNAs play a pivotal role in PDAC biology as they affect tumor growth, migration, and invasion by regulating cellular processes including cell cycle, apoptosis, and epithelial-mesenchymal transition. In this review, we focus on three types of well-established ncRNAs - microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) - and discuss their potential as diagnostic, prognostic and predictive biomarkers in PDAC.
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Biomarcadores de Tumor/metabolismo , Carcinoma Ductal Pancreático/patología , Regulación Neoplásica de la Expresión Génica , Neoplasias Pancreáticas/patología , ARN Largo no Codificante/genética , Animales , Biomarcadores de Tumor/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismoRESUMEN
Anaplastic large cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by a hyperactive anaplastic lymphoma kinase (ALK) fusion protein. ALK inhibitors, such as crizotinib, provide alternatives to standard chemotherapy with reduced toxicity and side effects. Children with lymphomas driven by nucleophosmin 1 (NPM1)-ALK fusion proteins achieved an objective response rate to ALK inhibition therapy of 54% to 90% in clinical trials; however, a subset of patients progressed within the first 3 months of treatment. The mechanism for the development of ALK inhibitor resistance is unknown. Through genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) activation and knockout screens in ALCL cell lines, combined with RNA sequencing data derived from ALK inhibitor-relapsed patient tumors, we show that resistance to ALK inhibition by crizotinib in ALCL can be driven by aberrant upregulation of interleukin 10 receptor subunit alpha (IL10RA). Elevated IL10RA expression rewires the STAT3 signaling pathway, bypassing otherwise critical phosphorylation by NPM1-ALK. IL-10RA expression does not correlate with response to standard chemotherapy in pediatric patients, suggesting that a combination of crizotinib and chemotherapy could prevent ALK inhibitor resistance-specific relapse.
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Antineoplásicos/farmacología , Crizotinib/farmacología , Resistencia a Antineoplásicos/genética , Subunidad alfa del Receptor de Interleucina-10/genética , Linfoma Anaplásico de Células Grandes/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/genética , Antineoplásicos/uso terapéutico , Sistemas CRISPR-Cas , Línea Celular , Crizotinib/uso terapéutico , Relación Dosis-Respuesta a Droga , Edición Génica , Expresión Génica , Humanos , Inmunohistoquímica , Subunidad alfa del Receptor de Interleucina-10/metabolismo , Linfoma Anaplásico de Células Grandes/tratamiento farmacológico , Linfoma Anaplásico de Células Grandes/metabolismo , Linfoma Anaplásico de Células Grandes/patología , Modelos Biológicos , Nucleofosmina , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
Palbociclib is a cyclin-dependent kinase (CDK) 4/CDK6 inhibitor approved for breast cancer that is estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-negative. We profiled palbociclib in cells either sensitive or resistant to the drug using an ATP/ADP probe-based chemoproteomics platform. Palbociclib only engaged CDK4 or CDK6 in sensitive cells. In resistant cells, no inhibition of CDK4 or CDK6 was observed, although the off-target profiles were similar in both cell types. Prolonged incubation of sensitive cells with the compound (24 h) resulted in the downregulation of additional kinases, including kinases critical for cell cycle progression. This downregulation is consistent with cell cycle arrest caused by palbociclib treatment. Both the direct and indirect targets were also observed in a human tumor xenograft study using the COLO-205 cell line in which phosphorylation of the retinoblastoma protein was tracked as the pharmacodyanamic marker. Together, these results suggest that this probe-based approach could be an important strategy toward predicting patient responsiveness to palbociclib.
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Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Neoplasias/patología , Piperazinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteómica , Piridinas/farmacología , Animales , Línea Celular Tumoral , Humanos , Ratones , Neoplasias/enzimología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND AND AIMS: Pain of propofol injection has been recalled by many patients as the most painful part of the induction of anesthesia. Tramadol and butorphanol are commonly used analgesics for perioperative analgesia in anesthesia practice. However, their potential to relieve propofol injection pain still needs to be explored. MATERIAL AND METHODS: A randomized, double-blind, placebo-controlled study was conducted on 90 American Society of Anesthesiologists I and II adult patients undergoing elective surgery under general anesthesia with propofol as an induction agent. Consecutive sampling technique with random assignment was used to allocate three groups of 30 patients each. Group I patients received an injection of normal saline 3 ml intravenously (placebo) while Group II and Group III patients received injection of tramadol 50 mg and butorphanol 1 mg intravenously, respectively. Before induction of anesthesia patients were asked about the intensity of pain on propofol injection by using visual analog scale (VAS) before the loss of consciousness. Descriptive statistics and analysis of variance with Chi-square test were used to analyze the data. The value of P < 0.05 was considered as a significant and P < 0.0001 as highly significant. RESULTS: The incidence of pain in Group I was observed in 80% of the patients, while it was observed in 23.33% and 20% of patients in Group II and III, respectively. Mean VAS scores were 2.27 ± 1.51, 1.14 ± 1.74, and 1.03 ± 1.72 in Group I, II, and Group III patients, respectively. The incidence of pruritus was 10% and 6.7% and erythema in 13.2% and 6.7% in Group II and III, respectively. CONCLUSION: Pretreatment with both butorphanol and tramadol significantly reduced pain on propofol injection; however, they exhibited comparable efficacy among each other. Thus, either of these two drugs can be considered for pretreatment to reduce propofol injection pain.
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Quinasa de Linfoma Anaplásico/antagonistas & inhibidores , Crizotinib/administración & dosificación , Resistencia a Antineoplásicos/efectos de los fármacos , Linfoma Anaplásico de Células Grandes , Inhibidores de Proteínas Quinasas/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Humanos , Linfoma Anaplásico de Células Grandes/tratamiento farmacológico , Linfoma Anaplásico de Células Grandes/enzimología , Linfoma Anaplásico de Células Grandes/mortalidad , Masculino , Persona de Mediana Edad , Recurrencia , Tasa de SupervivenciaRESUMEN
A co-crystal structure of amide-containing compound (4) in complex with the nicotinamide phosphoribosyltransferase (Nampt) protein and molecular modeling were utilized to design and discover a potent novel cyanoguanidine-containing inhibitor bearing a sulfone moiety (5, Nampt Biochemical IC50=2.5nM, A2780 cell proliferation IC50=9.7nM). Further SAR exploration identified several additional cyanoguanidine-containing compounds with high potency and good microsomal stability. Among these, compound 15 was selected for in vivo profiling and demonstrated good oral exposure in mice. It also exhibited excellent in vivo antitumor efficacy when dosed orally in an A2780 ovarian tumor xenograft model. The co-crystal structure of this compound in complex with the NAMPT protein was also determined.
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Antineoplásicos/farmacología , Citocinas/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Guanidinas/farmacología , Neoplasias Experimentales/tratamiento farmacológico , Nicotinamida Fosforribosiltransferasa/antagonistas & inhibidores , Neoplasias Ováricas/tratamiento farmacológico , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Femenino , Guanidinas/administración & dosificación , Guanidinas/química , Humanos , Ratones , Modelos Moleculares , Estructura Molecular , Nicotinamida Fosforribosiltransferasa/metabolismo , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
The heightened awareness of ethnic dermatology aligns with the growing prevalence of skin of color communities globally, where hyperpigmentation disorders pose a common dermatological challenge. Effectively addressing dermal pigmentation is challenging due to its resistance to conventional therapies and its association with impaired quality of life. This underscores the need for effective treatments and a thorough grasp of laser advancements. A relevant literature search spanning the last 7 years across the PubMed database reveals core studies, challenges, and the evolution of laser technologies tailored for various forms of congenital and acquired dermal hyperpigmentation in skin of color. This comprehensive review explores the mechanisms, applications, and recommendations for pigmentary laser technologies, highlighting the key role of Q-switched lasers in their established millisecond/ nanosecond forms and emerging picosecond lasers, fractional non-ablative and ablative lasers, Intense Pulsed Light, etc. The summary of evidence includes studies on dermal melanocytosis (nevus of Ota and Hori's nevus), tattoos, acquired dermal macular hyperpigmentation, etc., and also entities with mixed epidermal-dermal components, such as melasma and post-inflammatory hyperpigmentation. The review offers valuable insights for clinicians to make informed decisions based on diagnosis, skin type, and the latest technologies to optimize results and minimize complications, especially in darker Fitzpatrick skin types. In their five-year study with 122 Indian patients, the authors applied specific laser combinations for diverse dermal melanoses, including tattoos, dermal/mixed melasma, acquired dermal macular hyperpigmentation, and dermal nevi. Substantial pigmentation reduction, subjectively assessed by both physicians and patients, was observed across all groups. A one-way ANOVA indicated a significant difference in mean improvement scores across various pigmentary conditions (F = 3.39, p = 0.02), with melasma patients exhibiting a significantly higher improvement score than tattoos (p = 0.03). The results affirmed the safety and efficacy of sequential laser therapy for dermal pigmentation in skin of color, advocating for flexibility in approach while maintaining the rationale behind the laser sequences. Despite advancements, challenges persist, and gaps in the current literature are identified. In conclusion, this summary highlights the ongoing pursuit of optimal protocols in dermatological laser treatments for dermal melanoses, offering valuable insights for future research and clinical practice.
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ALK and ROS1 fusions are effectively targeted by tyrosine kinase inhibitors (TKIs), however patients inevitably relapse after an initial response, often due to kinase domain mutations. We investigated circulating DNA from TKI-relapsed NSCLC patients by deep-sequencing. New EML4::ALK substitutions, L1198R, C1237Y and L1196P, were identified in the plasma of NSCLC ALK patients and characterized in a Ba/F3 cell model. Variants C1237Y and L1196P demonstrated pan-inhibitor resistance across 5 clinical and 2 investigational TKIs.
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An in-depth multi-omic molecular characterisation of poly(adenosine 5'-diphosphate [ADP]-ribose) polymerase (PARP) inhibitors revealed a distinct poly-pharmacology of niraparib (Zejula®) mediated by its interaction with lanosterol synthase (LSS), which is not observed with other PARP inhibitors. Niraparib, in a similar way to the LSS inhibitor Ro-48-8071, induced activation of the 24,25-epoxysterol shunt pathway, which is a regulatory signalling branch of the cholesterol biosynthesis pathway. Interestingly, the combination of a LSS inhibitor with a PARP inhibitor that does not bind to LSS, such as olaparib, had an additive effect on killing of cancer cells to levels comparable to Niraparib as single agent. In addition, the combination of PARP inhibitors and statins, inhibitors of HMGCR, an enzyme catalysing the rate-limiting step in the mevalonate pathway, had a synergistic effect on tumor cell killing in cell lines and patient-derived ovarian tumor organoids. These observations suggest that concomitant inhibition of cholesterol biosynthesis pathway and PARP activity might result in stronger efficacy of these inhibitors against tumor types highly dependent on cholesterol metabolism.
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Microsatellite-unstable (MSI) cancers require WRN helicase to resolve replication stress due to expanded DNA (TA)n dinucleotide repeats. WRN is a promising synthetic lethal target for MSI tumors, and WRN inhibitors are in development. In this study, we used CRISPR-Cas9 base editing to map WRN residues critical for MSI cells, validating the helicase domain as the primary drug target. Fragment-based screening led to the development of potent and highly selective WRN helicase covalent inhibitors. These compounds selectively suppressed MSI model growth in vitro and in vivo by mimicking WRN loss, inducing DNA double-strand breaks at expanded TA repeats and DNA damage. Assessment of biomarkers in preclinical models linked TA-repeat expansions and mismatch repair alterations to compound activity. Efficacy was confirmed in immunotherapy-resistant organoids and patient-derived xenograft models. The discovery of potent, selective covalent WRN inhibitors provides proof of concept for synthetic lethal targeting of WRN in MSI cancer and tools to dissect WRN biology. Significance: We report the discovery and characterization of potent, selective WRN helicase inhibitors for MSI cancer treatment, with biomarker analysis and evaluation of efficacy in vivo and in immunotherapy-refractory preclinical models. These findings pave the way to translate WRN inhibition into MSI cancer therapies and provide tools to investigate WRN biology. See related commentary by Wainberg, p. 1369.
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Helicasa del Síndrome de Werner , Humanos , Helicasa del Síndrome de Werner/genética , Ratones , Animales , Inestabilidad de Microsatélites , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/patología , Línea Celular Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéuticoRESUMEN
Addition of newly generated neurons into mature neural circuits in the adult CNS responds to changes in neurotransmitter levels and is tightly coupled to the activity of specific brain regions. This postnatal neurogenesis contributes to plasticity of the olfactory bulb and hippocampus and is thought to play a role in learning and memory, context and odor discrimination, as well as perceptual learning. While acetylcholine plays an important role in odor discrimination and perceptual learning, its role in adult neurogenesis in the olfactory bulb has not been elucidated. In this study, I have examined the functional expression of nAChRs in progenitor cells of the rostral migratory stream (RMS) in the adult olfactory bulb of mice. I show that most of these cells in the RMS exhibit large nAChR-mediated calcium transients upon application of acetylcholine (ACh). Unlike in the hippocampus, the predominant functional nAChRs on progenitor cells are of α3ß4 subtype. Interestingly, functional receptor expression is lost once progenitor cells mature, and are incorporated into the granule cell layer. Instead, nAChRs are now expressed on some presynaptic terminals and modulate glutamate release onto granule cells. My results imply that ACh is a part of the permissive niche and likely plays a role in development of progenitor cells.
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Células Madre Adultas/metabolismo , Células-Madre Neurales/metabolismo , Bulbo Olfatorio/metabolismo , Subunidades de Proteína/metabolismo , Receptores Nicotínicos/metabolismo , Acetilcolina/metabolismo , Animales , Calcio/metabolismo , Señalización del Calcio , Ratones , Ratones Endogámicos C57BL , Bulbo Olfatorio/citología , Terminales Presinápticos/metabolismo , Subunidades de Proteína/química , Receptores Nicotínicos/químicaRESUMEN
The catalytic activity of porous platinum nanostructures, viz. platinum nanonets (PtNNs) and platinum nanoballs (PtNBs), synthesized by radiolysis were studied using two model reactions (i) electron transfer reaction between hexacyanoferrate (III) and sodium thiosulfate and (ii) the reduction of p-nitrophenol by sodium borohydride to p-aminophenol. The kinetic investigations were carried out for the platinum nanostructure-catalyzed reactions at different temperatures. The pseudofirst-order rate constant for the electron transfer reaction between hexacyanoferrate (III) and sodium thiosulfate catalyzed by PtNNs and PtNBs at 293 K are (9.1 ± 0.7) × 10(-3) min(-1) and (16.9 ± 0.6) × 10(-3) min(-1), respectively. For the PtNN- and PtNB-catalyzed reduction of p-nitrophenol to p-aminophenol by sodium borohydride, the pseudofirst-order rate constant was (8.4 ± 0.3) × 10(-2) min(-1) and (12.6 ± 2.5) × 10(-2) min(-1), respectively. The accessible surface area of the PtNNs and PtNBs determined before the reaction are 99 and 110 m(2)/g, respectively. These nanostructures exhibit significantly higher catalytic activity, consistent with the largest accessible surface area reported so far for the solid platinum nanoparticles. The equilibrium of the reactants on the surface of the platinum nanostructures played an important role in the induction time (t0) observed in the reaction. A possible role of structural modifications of PtNBs catalyzed the reaction leading to change in the accessible surface area of PtNBs is being explored to explain the nonlinear behavior in the kinetic curve. The activation energy of the PtNN- and PtNB-catalyzed reduction of p-nitrophenol are 26 and 6.4 kJ/mol, respectively. These observations open up new challenges in the field of material science to design and synthesize platinum nanostructures which could withstand such reaction conditions.
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Potent, reversible inhibition of the cytochrome P450 CYP2C9 isoform was observed in a series of urea-containing nicotinamide phosphoribosyltransferase (NAMPT) inhibitors. This unwanted property was successfully removed from the described inhibitors through a combination of structure-based design and medicinal chemistry activities. An optimized compound which did not inhibit CYP2C9 exhibited potent anti-NAMPT activity (17; BC NAMPT IC50=3 nM; A2780 antiproliferative IC50=70 nM), good mouse PK properties, and was efficacious in an A2780 mouse xenograft model. The crystal structure of this compound in complex with the NAMPT protein is also described.
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Hidrocarburo de Aril Hidroxilasas/antagonistas & inhibidores , Nicotinamida Fosforribosiltransferasa/antagonistas & inhibidores , Urea/análogos & derivados , Urea/farmacología , Animales , Hidrocarburo de Aril Hidroxilasas/química , Hidrocarburo de Aril Hidroxilasas/metabolismo , Citocromo P-450 CYP2C9 , Humanos , Ratones , Ratones Endogámicos BALB C , Nicotinamida Fosforribosiltransferasa/química , Nicotinamida Fosforribosiltransferasa/metabolismo , Urea/síntesis químicaRESUMEN
Potent, 1H-pyrazolo[3,4-b]pyridine-containing inhibitors of the human nicotinamide phosphoribosyltransferase (NAMPT) enzyme were identified using structure-based design techniques. Many of these compounds exhibited nanomolar antiproliferation activities against human tumor lines in in vitro cell culture experiments, and a representative example (compound 26) demonstrated encouraging in vivo efficacy in a mouse xenograft tumor model derived from the A2780 cell line. This molecule also exhibited reduced rat retinal exposures relative to a previously studied imidazo-pyridine-containing NAMPT inhibitor. Somewhat surprisingly, compound 26 was only weakly active in vitro against mouse and monkey tumor cell lines even though it was a potent inhibitor of NAMPT enzymes derived from these species. The compound also exhibited only minimal effects on in vivo NAD levels in mice, and these changes were considerably less profound than those produced by an imidazo-pyridine-containing NAMPT inhibitor. The crystal structures of compound 26 and the corresponding PRPP-derived ribose adduct in complex with NAMPT were also obtained.
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Amidas/química , Ácidos Carboxílicos/química , Citocinas/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Niacinamida/análogos & derivados , Nicotinamida Fosforribosiltransferasa/antagonistas & inhibidores , Pirazoles/química , Piridinas/química , Sulfonas/química , Amidas/síntesis química , Amidas/farmacocinética , Animales , Sitios de Unión , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Citocinas/metabolismo , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacocinética , Femenino , Semivida , Haplorrinos , Humanos , Ratones , Ratones Desnudos , NAD/metabolismo , Niacinamida/sangre , Niacinamida/química , Niacinamida/farmacocinética , Nicotinamida Fosforribosiltransferasa/metabolismo , Estructura Terciaria de Proteína , Pirazoles/sangre , Pirazoles/farmacocinética , Ratas , Retina/efectos de los fármacos , Retina/metabolismo , Relación Estructura-Actividad , Sulfonas/sangre , Sulfonas/farmacocinética , Trasplante HeterólogoRESUMEN
The nine Viola pilosa Blume populations studied from Pir Panjal contained 20 chromosomes. This count is not reported so far in Indian populations. Currently, comparison of tapetal and meiotic cells revealed the existence of synchrony in different developmental phases. Young tapetal cells at prometaphase co-occurred with the pollen mother cells (PMCs) at diakinesis to metaphase, mature tapetal cells with disintegrated chromatin material co-occurred with tetrads and no tapetal cells were found at mature pollen stage. Cytological studies in young tapetal cells revealed most of these to be endopolyploid, with each having 40 chromosomes. While outnumbering somatic cells contained clear 40 chromosomes which seemed to be the outcome of endomitosis, a sizeable number of cells possessed 40 sticky chromosomes at metaphase. Later chromosomes are likely to form restitution nucleus. Mature tapetal cells, occurring singly/cytomictically connected (3.2-26.31%) or showing coalescence (10.5-22.8%), did not contain recognizable chromosomes. Instead, they were characterized by disintegrated nuclear content. Further, meiotic studies revealed that the present population contained all/outnumbering euploid cells (2n=20); many of which exhibited nearly regular behaviour. However, 6.5-26.9% meiocytes of eight populations and 47% cells of P-Khe population depicted aneuploidy/contained quadri-octavalents, with per cent pollen viabilities of these ranging from 38.6 to 49.9. Going by the normal tapetal development in V. pilosa, existence of various chromosomal anomalies seems to have accounted for the reduction in gametic fertility of this taxon.
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Trastornos de los Cromosomas , Viola , Metafase , Diploidia , Reproducción , MeiosisRESUMEN
We studied the caring, parenting, and support services for children with special needs in Ghana. Many of the study participants reported re-adjusting their lives in virtually every domain-social, economic, and emotional to deal with and manage the new realities. How parents navigate this space varied considerably from setting to setting. Regardless of individual and interpersonal resources, community, institutional, and policy circumstances seemed to exacerbate notions of disability. In many instances, parents had a low depth of suspicion about the precursors to disabling events in their children. Parents are constantly pursuing health care, including a cure for their children with disabilities. Views about "otherness" were noted, and these tended to undermine medical interpretations/explanations of disability generally, which in turn affected formal education and health-seeking for children. Institutional arrangements exist to encourage parents to invest in their children regardless of their perceived abilities. However, these do not seem to be sufficient, particularly for health and formal education. Programming and policy implications are highlighted.