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1.
Nano Lett ; 24(18): 5413-5419, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38669591

RESUMEN

Motional narrowing implies narrowing induced by motion; for example, in nuclear magnetic resonance, the thermally induced random motion of the nuclei in an inhomogeneous environment leads to a counterintuitive narrowing of the resonance line. Similarly, the excitons in monolayer semiconductors experience magnetic inhomogeneity: the electron-hole spin-exchange interaction manifests as an in-plane pseudomagnetic field with a periodically varying orientation inside the exciton band. The excitons undergo random momentum scattering and pseudospin precession repeatedly in this inhomogeneous magnetic environment, typically resulting in fast exciton depolarization. On the contrary, we show that such magnetic inhomogeneity averages out at high scattering rates due to motional narrowing. Physically, a faster exciton scattering leads to a narrower pseudospin distribution on the Bloch sphere, implying a nontrivial improvement in exciton polarization. The in-plane nature of the pseudomagnetic field enforces a contrasting scattering dependence between the circularly and linearly polarized excitons, providing a spectroscopic way to gauge the sample quality.

2.
Arch Microbiol ; 206(5): 205, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38573383

RESUMEN

Honeybees are vital for global crop pollination, making indispensable contributions to agricultural productivity. However, these vital insects are currently facing escalating colony losses on a global scale, primarily attributed to parasitic and pathogenic attacks. The prevalent response to combat these infections may involve the use of antibiotics. Nevertheless, the application of antibiotics raises concerns regarding potential adverse effects such as antibiotic resistance and imbalances in the gut microbiota of bees. In response to these challenges, this study reviews the utilization of a probiotic-supplemented pollen substitute diet to promote honeybee gut health, enhance immunity, and overall well-being. We systematically explore various probiotic strains and their impacts on critical parameters, including survival rate, colony strength, honey and royal jelly production, and the immune response of bees. By doing so, we emphasize the significance of maintaining a balanced gut microbial community in honeybees. The review also scrutinizes the factors influencing the gut microbial communities of bees, elucidates the consequences of dysbiosis, and evaluates the potential of probiotics to mitigate these challenges. Additionally, it delineates different delivery mechanisms for probiotic supplementation and elucidates their positive effects on diverse health parameters of honeybees. Given the alarming decline in honeybee populations and the consequential threat to global food security, this study provides valuable insights into sustainable practices aimed at supporting honeybee populations and enhancing agricultural productivity.


Asunto(s)
Apicultura , Probióticos , Abejas , Animales , Agricultura , Antibacterianos , Disbiosis
3.
Int J Gynecol Pathol ; 41(2): 157-160, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33782342

RESUMEN

Mucinous differentiation of the endometrium can occur in a spectrum of changes ranging from benign (metaplasia) to malignant (adenocarcinomas with mucinous differentiation). A rarer differential which is usually not considered is a teratoma. We present a case of a 55-yr-old woman with history of irregular perimenopausal bleeding. Endometrial curetting revealed proliferative mucinous epithelium on histology raising a possibility of low-grade epithelial mucinous malignancy. Hysterectomy was performed and histologic examination revealed a diagnosis of uterine mature teratoma. Mature cystic teratoma of the lower uterine segment is very rare and presence of just one element such as mucinous epithelium can lead to a misdiagnosis of carcinoma on biopsy or curetting.


Asunto(s)
Endometrio , Teratoma , Endometrio/patología , Endometrio/cirugía , Epitelio/patología , Femenino , Humanos , Histerectomía , Teratoma/patología , Útero/patología
4.
Arch Pharm (Weinheim) ; 355(11): e2200081, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35924298

RESUMEN

Fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) are the primary catabolic enzymes for endocannabinoids, anandamide (AEA), and 2-arachidonoyl glycerol. Numerous studies have shown that FAAH and MAGL play an important role in modulating various central nervous system activities; hence, the development of small molecule FAAH/MAGL inhibitors is an active area of research. Several small molecules possessing the carbamate scaffold are documented as potential FAAH/MAGL inhibitors. Here, we designed and synthesized a series of open chain and cyclic carbamates and evaluated their dual FAAH-MAGL inhibition properties. Phenyl [4-(piperidin-1-ylmethyl)phenyl]carbamate (2e) emerged as the most potent MAGL inhibitor (IC50 = 19 nM), benzyl (1H-benzo[d]imidazol-2-yl)carbamate (3h) was the most potent FAAH inhibitor (IC50 = 55 nM), and phenyl (6-fluorobenzo[d]thiazol-2-yl)carbamate (2i) egressed as a nonselective dual FAAH-MAGL inhibitor (FAAH: 82 nM, MAGL: 72 nM). The enzyme kinetics experiments revealed that the compounds inhibit FAAH/MAGL in a covalent-reversible manner, with a mixed binding mode of action. Moreover, the lead compounds were found suitable for blood-brain permeation in the parallel artificial membrane permeation assay. Furthermore, docking simulation experiments suggested that the potency of the lead compounds was governed by hydrogen bonds and hydrophobic interactions with the enzyme active sites. In silico drug-likeness and ADMETox prediction studies provided useful information on the compounds' oral absorption, metabolism, and toxicity profiles. In summary, this study afforded potent multifunctional carbamates with appreciable pharmacokinetic profiles meriting further investigation.


Asunto(s)
Carbamatos , Monoacilglicerol Lipasas , Monoacilglicerol Lipasas/metabolismo , Monoglicéridos , Relación Estructura-Actividad , Inhibidores Enzimáticos , Amidohidrolasas
5.
Blood ; 133(17): 1899-1908, 2019 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-30700419

RESUMEN

The metalloprotease ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats member 13) prevents microvascular thrombosis by cleaving von Willebrand factor (VWF) within platelet-rich thrombi, and cleavage depends on allosteric activation of ADAMTS13 by the substrate VWF. Human ADAMTS13 has a short propeptide, metalloprotease (M), disintegrin-like (D), thrombospondin-1 (T), Cys-rich (C), and spacer (S) domains (proximal domains), followed by 7 T and 2 CUB (complement components C1r and C1s, sea urchin protein Uegf, and bone morphogenetic protein-1) domains (distal domains). Distal domains inhibit the catalytic proximal domains; binding of distal T8-CUB domains to the VWF D4 domain relieves autoinhibition and promotes cleavage of the nearby VWF A2 domain. However, the role of specific ADAMTS13 distal domains in this allosteric mechanism is not established. Assays of plasma ADAMTS13 from 20 placental mammals, birds, and amphibians show that allosteric regulation is broadly conserved, and phylogenetic analysis of 264 vertebrates shows the long propeptide, T3, T4, T6, and T6a domains have been deleted several times in placental mammals, birds, and fish. Notably, pigeon ADAMTS13 has only 3 distal T domains but was activated normally by human VWF D4 and cleaved VWF multimers, preferentially under fluid shear stress. Human ADAMTS13 constructed to resemble pigeon ADAMTS13 retained normal allosteric regulation and shear-dependent cleavage of VWF. Thus, the T3-T6 domains of human ADAMTS13 are dispensable. Conversely, deletion of T7 or T8 abolished allosteric activation. For most species, some sequence changes in the VWF substrate can markedly increase the rate of cleavage, suggesting that ADAMTS13 and VWF have not evolved to be optimal enzyme-substrate pairs. These properties may reflect evolutionary pressure to balance the risk for VWF-dependent bleeding and thrombosis.


Asunto(s)
Proteína ADAMTS13/metabolismo , Evolución Molecular , Filogenia , Proteínas Recombinantes/metabolismo , Factor de von Willebrand/metabolismo , Regulación Alostérica , Secuencia de Aminoácidos , Animales , Dominio Catalítico , Humanos , Unión Proteica , Homología de Secuencia , Especificidad por Sustrato
6.
Blood ; 133(17): 1909-1918, 2019 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-30692120

RESUMEN

Human ADAMTS13 is a multidomain protein with metalloprotease (M), disintegrin-like (D), thrombospondin-1 (T), Cys-rich (C), and spacer (S) domains, followed by 7 additional T domains and 2 CUB (complement components C1r and C1s, sea urchin protein Uegf, and bone morphogenetic protein-1) domains. ADAMTS13 inhibits the growth of von Willebrand factor (VWF)-platelet aggregates by cleaving the cryptic Tyr1605-Met1606 bond in the VWF A2 domain. ADAMTS13 is regulated by substrate-induced allosteric activation; without shear stress, the distal T8-CUB domains markedly inhibit VWF cleavage, and binding of VWF domain D4 or selected monoclonal antibodies (MAbs) to distal ADAMTS13 domains relieves this autoinhibition. By small angle X-ray scattering (SAXS), ADAMTS13 adopts a hairpin-like conformation with distal T7-CUB domains close to the proximal MDTCS domains and a hinge point between T4 and T5. The hairpin projects like a handle away from the core MDTCS and T7-CUB complex and contains distal T domains that are dispensable for allosteric regulation. Truncated constructs that lack the T8-CUB domains are not autoinhibited and cannot be activated by VWF D4 but retain the hairpin fold. Allosteric activation by VWF D4 requires T7, T8, and the 58-amino acid residue linker between T8 and CUB1. Deletion of T3 to T6 produced the smallest construct (delT3-6) examined that could be activated by MAbs and VWF D4. Columba livia (pigeon) ADAMTS13 (pADAMTS13) resembles human delT3-6, retains normal activation by VWF D4, and has a SAXS envelope consistent with amputation of the hairpin containing the dispensable T domains of human ADAMTS13. Our findings suggest that human delT3-6 and pADAMTS13 approach a "minimal" structure for allosterically regulated ADAMTS13.


Asunto(s)
Proteína ADAMTS13/química , Proteína ADAMTS13/metabolismo , Mutación , Estructura Terciaria de Proteína , Dispersión del Ángulo Pequeño , Factor de von Willebrand/metabolismo , Proteína ADAMTS13/genética , Regulación Alostérica , Sitios de Unión , Dominio Catalítico , Humanos , Modelos Moleculares , Mutagénesis , Unión Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
J Stroke Cerebrovasc Dis ; 30(3): 105537, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33338706

RESUMEN

BACKGROUND: Intracerebral hemorrhage (ICH) is associated with high mortality, morbidity, and recurrence. Studies have reported the accuracy of several blood biomarkers in predicting clinical outcomes; however, their independent contribution in prediction remains to be established. AIM: To investigate the incremental accuracy in predicting clinical outcomes in patients with ICH in a north Indian population using blood-based biomarkers. METHODS: In this study, a total of 250 ICH cases were recruited within 72 hours of onset. Baseline clinical and CT scan measurement were recorded. Homocysteine (HCY), C-reactive protein (CRP), matrix metalloproteinase-9 (MMP9), E-selectin (SELE), and P-selectin (SELP) levels were measured through ELISA. Telephonic follow-up was done by using mRS scale at three months. RESULTS: The mean age of cohort was 54.9 (SD±12.8) years with 64.8% patients being male. A total of 109 (43.6%) deaths were observed over three months follow-up. Area under the receiver operating characteristics curve-(AUROC) for 90-day mortality were 0.55 (HCY), 0.62 (CRP), 0.57 (MMP9), 0.60 (SELE) and 0.53 (SELP) and for poor outcome at 90-day (mRS: 3-6) were 0.60 (HCY), 0.62 (CRP), 0.54 (MMP9), 0.67 (SELE) and 0.54 (SELP). In multivariable model including age, ICH volume, IVH and GCS at admission, serum SELE (p=0.004) significant for poor outcome with improved AUROC (0.86) and HCY (p=0.04), CRP (p=0.003) & MMP9 (p=0.02) for mortality with least Akaike's Information Criterion-(AIC) (1060.5). CONCLUSIONS: Our findings suggest that the serum SELE is a significant predictor of poor outcome and HCY, CRP & MMP9 for Mortality in patients with ICH in the north Indian population.


Asunto(s)
Proteína C-Reactiva/análisis , Hemorragia Cerebral/sangre , Selectina E/sangre , Homocisteína/sangre , Metaloproteinasa 9 de la Matriz/sangre , Adulto , Anciano , Biomarcadores/sangre , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/mortalidad , Hemorragia Cerebral/cirugía , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
8.
Proc Natl Acad Sci U S A ; 114(32): 8649-8654, 2017 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-28739898

RESUMEN

Human brown adipose tissue (BAT) can be activated to increase glucose uptake and energy expenditure, making it a potential target for treating obesity and metabolic disease. Data on the functional and anatomic characteristics of BAT are limited, however. In 20 healthy young men [12 lean, mean body mass index (BMI) 23.2 ± 1.9 kg/m2; 8 obese, BMI 34.8 ± 3.3 kg/m2] after 5 h of tolerable cold exposure, we measured BAT volume and activity by 18F-labeled fluorodeoxyglucose positron emission tomography/computerized tomography (PET/CT). Obese men had less activated BAT than lean men (mean, 130 vs. 334 mL) but more fat in BAT-containing depots (mean, 1,646 vs. 855 mL) with a wide range (0.1-71%) in the ratio of activated BAT to inactive fat between individuals. Six anatomic regions had activated BAT-cervical, supraclavicular, axillary, mediastinal, paraspinal, and abdominal-with 67 ± 20% of all activated BAT concentrated in a continuous fascial layer comprising the first three depots in the upper torso. These nonsubcutaneous fat depots amounted to 1.5% of total body mass (4.3% of total fat mass), and up to 90% of each depot could be activated BAT. The amount and activity of BAT was significantly influenced by region of interest selection methods, PET threshold criteria, and PET resolutions. The present study suggests that active BAT can be found in specific adipose depots in adult humans, but less than one-half of the fat in these depots is stimulated by acute cold exposure, demonstrating a previously underappreciated thermogenic potential.


Asunto(s)
Tejido Adiposo Pardo/diagnóstico por imagen , Adiposidad , Índice de Masa Corporal , Obesidad/diagnóstico por imagen , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Tejido Adiposo Pardo/metabolismo , Adulto , Glucosa-6-Fosfato/administración & dosificación , Glucosa-6-Fosfato/análogos & derivados , Humanos , Masculino , Obesidad/metabolismo
9.
J Indian Assoc Pediatr Surg ; 25(1): 52-54, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31896902

RESUMEN

Priapism is an uncommon presentation in children and adults with a chronic myeloid type of leukemia. Its association is rarely found in an acute lymphoblastic type of leukemia (ALL). Timely management is important to prevent irreversible complications. We report a case of ALL with presenting complaint of priapism.

10.
Cancer ; 125(8): 1258-1266, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30644531

RESUMEN

BACKGROUND: Somatic mutations in hypoxia-inducible factor 2α (HIF2A) are associated with polycythemia-paraganglioma syndrome. Specifically, the classic presentation of female patients with recurrent paragangliomas (PGLs), polycythemia (at birth or in early childhood), and duodenal somatostatinomas has been described. Studies have demonstrated that somatic HIF2A mutations occur as postzygotic events and some to be associated with somatic mosaicism affecting hematopoietic and other tissue precursors. This phenomenon could explain the development of early onset of polycythemia in the absence of erythropoietin-secreting tumors. METHODS: Correlation analysis was performed between mosaicism of HIF2A mutant patients and clinical presentations. RESULTS: Somatic HIF2A mutations (p.A530V, p.P531S, and p.D539N) were identified in DNA extracted from PGLs of 3 patients. No somatic mosaicism was detected through deep sequencing of blood genomic DNA. Compared with classic syndrome, both polycythemia and PGL in all 3 patients developed at an advanced age with polycythemia at age 30, 30, and 17 years and PGLs at age 34, 30, and 55 years, respectively. Somatostatinomas were not detected, and 2 patients had ophthalmic findings. The biochemical phenotype in all 3 patients was noradrenergic with 18 F-fluorodopa PET/CT as the most sensitive imaging modality. All patients demonstrated multiplicity, and none developed metastatic disease. CONCLUSION: These findings suggest that newer techniques need to be developed to detect somatic mosaicism in patients with this syndrome. Absence of HIF2A mosaicism in patients with somatic HIF2A mutations supports association with late onset of the disease, milder clinical phenotype, and an improved prognosis compared with patients who have HIF2A mosaicism.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Paraganglioma/clasificación , Mutación Puntual , Policitemia/clasificación , Adolescente , Adulto , Edad de Inicio , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Persona de Mediana Edad , Mosaicismo , Paraganglioma/diagnóstico por imagen , Paraganglioma/genética , Policitemia/diagnóstico por imagen , Policitemia/genética , Tomografía Computarizada por Tomografía de Emisión de Positrones , Análisis de Secuencia de ADN
11.
Eur J Nucl Med Mol Imaging ; 45(5): 787-797, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29204718

RESUMEN

PURPOSE: To evaluate and compare diagnostic performance of 68Ga-DOTA(0)-Tyr(3)-octreotate (68Ga-DOTATATE) with 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography-computed tomography (PET/CT) and anatomic imaging using computed tomography and/or magnetic resonance (CT/MR) imaging in detection of SDHx-related pheochromocytomas and paragangliomas (PPGLs) in pediatric patients. METHODS: Nine pediatric patients (5:4, girls:boys; 14.6 ± 2.0 years) with an SDHx-related mutation (SDHB:SDHA:SDHD, n = 7:1:1) were included in this retrospective study. At the time of initial diagnosis, 7/9 patients had metastatic disease. They underwent CT/MR imaging along with PET/CT using 68Ga-DOTATATE (n = 9), 18F-FDG (n = 8), and positron emission tomography-magnetic resonance imaging (PET/MR) using 18F-FDG (n = 1). In this manuscript, 18F-FDG PET/CT refers to both 18F-FDG PET/CT and 18F-FDG PET/MR. The per-lesion, per-region, and per-patient detection rates were compared and calculated for each of the imaging modalities. A composite of all functional and anatomic imaging studies served as the imaging comparator. RESULTS: Eight out of nine patients were positive for PPGLs on the imaging studies that demonstrated 107 lesions in 22 anatomic regions on the imaging comparator. The per-lesion detection rates for 68Ga-DOTATATE PET/CT, 18F-FDG PET/CT, and CT/MR imaging were 93.5% (95%CI, 87.0% to 97.3%); 79.4% (95%CI, 70.5% to 86.6%); and 73.8% (95%CI, 64.5% to 81.9%), respectively. The per-lesion detection rate for 68Ga-DOTATATE PET/CT was significantly higher than that of 18F-FDG PET/CT (p = 0.001) or CT/MR imaging (p < 0.001). In all of the anatomic regions except abdomen, the per-lesion detection rates for 68Ga-DOTATATE PET/CT was found to be equal or superior to 18F-FDG PET/CT, and CT/MR imaging. The per-region detection rate was 100% (95%CI, 84.6% to 100%) for 68Ga-DOTATATE PET/CT and 90.9% (95%CI, 70.8% to 98.9%) for both 18F-FDG PET/CT and CT/MR imaging. The per-patient detection rates for 68Ga-DOTATATE PET/CT, 18FDG PET/CT, and CT/MR imaging were all 100% (95%CI, 63.1% to 100%). CONCLUSION: Our preliminary study demonstrates the superiority of 68Ga-DOTATATE PET/CT in localization of SDHx-related PPGLs in pediatric population compared to 18F-FDG PET/CT and CT/MR imaging with the exception of abdominal (excluding adrenal and liver) lesions, and suggests that it might be considered as a first-line imaging modality in pediatric patients with SDHx-related PPGLs.


Asunto(s)
Mutación , Compuestos Organometálicos , Paraganglioma/genética , Feocromocitoma/genética , Tomografía Computarizada por Tomografía de Emisión de Positrones , Succinato Deshidrogenasa/genética , Adolescente , Niño , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Paraganglioma/diagnóstico por imagen , Feocromocitoma/diagnóstico por imagen , Tomografía de Emisión de Positrones , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
12.
BMC Cancer ; 18(1): 286, 2018 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-29534684

RESUMEN

BACKGROUND: The role of the hypoxia signaling pathway in the pathogenesis of pheochromocytoma/paraganglioma (PPGL)-polycythemia syndrome has been elucidated. Novel somatic mutations in hypoxia-inducible factor type 2A (HIF2A) and germline mutations in prolyl hydroxylase type 1 and type 2 (PHD1 and PHD2) have been identified to cause upregulation of the hypoxia signaling pathway and its target genes including erythropoietin (EPO) and its receptor (EPOR). However, in a minority of patients presenting with this syndrome, the genetics and molecular pathogenesis remain unexplained. The aim of the present study was to uncover novel genetic causes of PPGL-polycythemia syndrome. CASE PRESENTATION: A female presented with a history of JAK2V617F positive PV, diagnosed in 2007, and right adrenal pheochromocytoma diagnosed and resected in 2011. Her polycythemia symptoms and hematocrit levels continued to worsen from 2007 to 2011, with an increased frequency of phlebotomies. Postoperatively, until early 2013, her hematocrit levels remained normalized. Following this, the hematocrit levels ranged between 46.4 and 48.9% [35-45%]. Tumor tissue from the patient was further tested for mutations in genes related to upregulation of the hypoxia signaling pathway including iron regulatory protein 1 (IRP1), which is a known regulator of HIF-2α mRNA translation. Functional studies were performed to investigate the consequences of these mutations, especially their effect on the HIF signaling pathway and EPO. Indel mutations (c.267-1_267delGGinsTA) were discovered at the exon 3 splicing site of IRP1. Minigene construct and splicing site analysis showed that the mutation led to a new splicing site and a frameshift mutation of IRP1, which caused a truncated protein. Fluorescence in situ hybridization analysis demonstrated heterozygous IRP1 deletions in tumor cells. Immunohistochemistry results confirmed the truncated IRP1 and overexpressed HIF-2α, EPO and EPOR in tumor cells. CONCLUSIONS: This is the first report which provides direct molecular genetic evidence of association between a somatic IRP1 loss-of-function mutation and PHEO and secondary polycythemia. In patients diagnosed with PHEO/PGL and polycythemia with negative genetic testing for mutations in HIF2A, PHD1/2, and VHL, IRP1 should be considered as a candidate gene.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Mutación de Línea Germinal , Proteína 1 Reguladora de Hierro/genética , Janus Quinasa 2/genética , Feocromocitoma/genética , Policitemia Vera/genética , Empalme del ARN , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasias de las Glándulas Suprarrenales/patología , Adulto , Femenino , Humanos , Feocromocitoma/complicaciones , Feocromocitoma/patología , Policitemia Vera/complicaciones , Policitemia Vera/patología , Pronóstico
13.
Endocr Pract ; 23(6): 690-704, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28332883

RESUMEN

OBJECTIVE: Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors known to produce and secrete high levels of circulating catecholamines and their metabolites. The biochemical characteristics of these tumors can be used to divide them into three major phenotypes. The adrenergic, noradrenergic and dopaminergic phenotypes are defined by predominant elevations in epinephrine and metanephrine, norepinephrine and normetanephrine, and dopamine and 3-methoxytyramine, respectively. There are over 15 well-identified tumor-susceptibility genes responsible for approximately 40% of the cases. The objective of this review article is to outline specific genotype/biochemical phenotype relationships. METHODS: Literature review. RESULTS: None. CONCLUSION: Biochemical phenotype of PPGL is determined by the underlying genetic mutation and the associated molecular pathway. Identification of genotype/biochemical relationships is valuable in prioritizing testing for specific genes, making treatment decisions and monitoring disease progression. ABBREVIATIONS: 3-MT = 3-methoxytyramine; EPAS1 = endothelial pas domain protein 1; FH = fumarate hydratase; HIF2A = hypoxia inducible factor type 2A; MEN2 = multiple endocrine neoplasia type 2; NF1 = neurofibromatosis type 1; PNMT = phenylethanolamine N-methyltransferase; PPGL = pheochromocytoma and paraganglioma; RET = rearranged during transfection; SDH = succinate dehydrogenase; SDHAF2 = succinate dehydrogenase complex assembly factor 2; TCA = tricarboxylic acid; TH = tyrosine hydroxylase; TMEM127 = transmembrane protein 127; VHL = von Hippel-Lindau.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Feocromocitoma/genética , Neoplasias de las Glándulas Suprarrenales/metabolismo , Dopamina/metabolismo , Epinefrina/metabolismo , Genotipo , Humanos , Norepinefrina/metabolismo , Paraganglioma/genética , Paraganglioma/metabolismo , Fenotipo , Feocromocitoma/metabolismo , Medicina de Precisión
14.
Proc Natl Acad Sci U S A ; 111(52): 18584-9, 2014 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-25512528

RESUMEN

The metalloprotease ADAMTS13 cleaves von Willebrand factor (VWF) within endovascular platelet aggregates, and ADAMTS13 deficiency causes fatal microvascular thrombosis. The proximal metalloprotease (M), disintegrin-like (D), thrombospondin-1 (T), Cys-rich (C), and spacer (S) domains of ADAMTS13 recognize a cryptic site in VWF that is exposed by tensile force. Another seven T and two complement C1r/C1s, sea urchin epidermal growth factor, and bone morphogenetic protein (CUB) domains of uncertain function are C-terminal to the MDTCS domains. We find that the distal T8-CUB2 domains markedly inhibit substrate cleavage, and binding of VWF or monoclonal antibodies to distal ADAMTS13 domains relieves this autoinhibition. Small angle X-ray scattering data indicate that distal T-CUB domains interact with proximal MDTCS domains. Thus, ADAMTS13 is regulated by substrate-induced allosteric activation, which may optimize VWF cleavage under fluid shear stress in vivo. Distal domains of other ADAMTS proteases may have similar allosteric properties.


Asunto(s)
Proteínas ADAM/química , Factor de von Willebrand/química , Proteínas ADAM/sangre , Proteínas ADAM/genética , Proteína ADAMTS13 , Regulación Alostérica/fisiología , Activación Enzimática/fisiología , Humanos , Unión Proteica , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Factor de von Willebrand/genética , Factor de von Willebrand/metabolismo
15.
Bioorg Med Chem ; 23(4): 839-48, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25618595

RESUMEN

We report herein the design and synthesis of bioisosteres of spirooxindole (MI-63/219), a small-molecule inhibitors of the MDM2-p53 interaction as anti-breast cancer agents. Compound 5b has been exhibiting significant anti-proliferative activity in nude mice bearing MCF-7 xenograft tumor. The compound 5b was found to act via modulation of MDM2 and p53 expression in breast cancer cells expressing wild type p53. Compound 5b stimulated p53 activation, caused modulation of downstream effectors p21, pRb, and cyclin D1 which regulate cell cycle. Thus, compound triggered G1-S phase cell cycle arrest, which was evident by flow cytometric analysis of treated breast cancer cells. Thus, compound 5b restores the p53 function, which triggers molecular events consistent with cell cycle arrest at G1/S phase.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Indoles/química , Indoles/uso terapéutico , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Antineoplásicos/farmacología , Mama/efectos de los fármacos , Mama/metabolismo , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Diseño de Fármacos , Femenino , Humanos , Indoles/farmacología , Ratones Desnudos , Oxindoles , Mapas de Interacción de Proteínas/efectos de los fármacos , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , Compuestos de Espiro/uso terapéutico , Proteína p53 Supresora de Tumor/antagonistas & inhibidores
17.
Bioorg Chem ; 56: 8-15, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24893208

RESUMEN

A novel series of pyrazole derivatives were synthesized and evaluated in vivo for their anti-inflammatory activity in carrageenan-induced rat paw edema model. Among all compounds, 5a, and 5b showed comparable anti-inflammatory activity to Nimesulide, the standard drug taken for the studies. In silico (docking) studies were carried out to investigate the theoretical binding mode of the compounds to target the cyclooxygenase (COX-2) using Autodock 4.2.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Edema/tratamiento farmacológico , Pirazoles/farmacología , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa/síntesis química , Inhibidores de la Ciclooxigenasa/química , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Estructura Molecular , Pirazoles/síntesis química , Pirazoles/química , Ratas , Ratas Wistar , Relación Estructura-Actividad
18.
Clin Case Rep ; 12(2): e8361, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38314184

RESUMEN

Monoclonal gammopathy of uncertain significance associated acquired von Willebrand syndrome is a serious bleeding condition driven by immunological clearance of von Willebrand factor and has limited treatment options. We present a patient who achieved durable remission through eradication of the monoclonal paraprotein with clonal directed therapy with bortezomib.

19.
Waste Manag ; 182: 164-174, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38653044

RESUMEN

The current study introduces an innovative methodology by utilizing treated wastewater (TWW) from an effluent treatment plant as a washing agent to enhance the characteristics of incineration bottom ash (IBA). This approach addresses sustainability concerns and promotes the circular economy by reusing wastewater generated in municipal solid waste incineration facilities. Previous research has underscored the challenges of open IBA reuse due to elevated leaching of chlorides, sulfates, and trace metal(loid)s. Thus, the experimental setup explores various combinations of washing, with or without screening, to optimize the properties of soil-like material (SLM < 4.75 mm) and overall material (OM < 31.5 mm) fractions of IBA for unrestricted applications. Batch leaching tests were conducted on treated samples, and leaching characteristics were evaluated in accordance with regulatory standards, primarily the Dutch standard for unrestricted IBA reuse. The findings reveal that washing in isolation proves insufficient to enhance IBA properties; however, washing followed by screening, specifically for removing fines (<0.15 mm), proves effective in reducing contamination. The study identifies that multiple steps of washing and screening (with recirculation) process render OM and SLM fractions suitable for unrestricted reuse with a cumulative liquid-to-solid ratio of 6 L/kg and a total washing time of 15 min. The multi-step treatment was found effective in reducing sulfate contamination by 65-74 % and chloride contamination by 83-89 % in IBA fractions. This approach offers a promising solution for overcoming the limitations associated with IBA leaching, thereby promoting sustainable waste reuse practices.


Asunto(s)
Incineración , Aguas Residuales , Incineración/métodos , Aguas Residuales/química , Residuos Sólidos/análisis , Reciclaje/métodos , Ceniza del Carbón/análisis , Ceniza del Carbón/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis
20.
Prog Mol Biol Transl Sci ; 204: 219-248, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38458739

RESUMEN

RNA therapeutics have emerged as potential treatments for genetic disorders, infectious diseases, and cancer. RNA delivery to target cells for efficient therapeutic applications remains challenging due to instability and poor uptake. Polymeric nanoparticulate delivery systems offer stability, protection, and controlled release. These systems shield RNA from degradation, enabling efficient uptake and extended circulation. Various polymeric nanoparticle platforms have been explored, including lipid-based nanoparticles, polymeric micelles, dendrimers, and polymer-drug conjugates. This review outlines recent breakthroughs of recent advances, design principles, characterization techniques, and performance evaluation of these delivery systems. It highlights their potential in translating preclinical studies into clinical applications. Additionally, the review discusses the application of polymeric nanoparticles in ophthalmic drug delivery, particularly for medications that dissolve poorly in water, and the progress made in siRNA-based therapies for viral infections, autoimmune diseases, and cancers. SiRNA holds great promise for precision medicine and therapeutic intervention, with the ability to target specific genes and modulate disease-associated pathways. The versatility and potency of siRNA-based drugs offer a broader scope for therapeutic intervention compared to traditional biological drugs. As research in RNA therapeutics continues to advance, these technologies hold tremendous potential to revolutionize the treatment of various diseases and improve patient outcomes.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Neoplasias/terapia , Sistemas de Liberación de Medicamentos , ARN Interferente Pequeño/uso terapéutico , ARN Interferente Pequeño/genética , Polímeros
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