Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Pathogens ; 11(11)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36365000

RESUMEN

Despite entering an endemic phase, SARS-CoV-2 remains a significant burden to public health across the global community. Wastewater sampling has consistently proven utility to understanding SARS-CoV-2 prevalence trends and genetic variation as it represents a less biased assessment of the corresponding communities. Here, we report that ongoing monitoring of SARS-CoV-2 genetic variation in samples obtained from the wastewatersheds of the city of Louisville in Jefferson county Kentucky has revealed the periodic reemergence of the Delta strain in the presence of the presumed dominant Omicron strain. Unlike previous SARS-CoV-2 waves/emergence events, the Delta reemergence events were geographically restricted in the community and failed to spread into other areas as determined by wastewater analyses. Moreover, the reemergence of the Delta strain did not correlate with vaccination rates as communities with lower relative vaccination have been, to date, not affected. Importantly, Delta reemergence events correlate with increased public health burdens, as indicated by increased daily case rates and mortality relative to non-Delta wastewatershed communities. While the underlying reasons for the reemergence of the Delta variant remain unclear, these data reaffirm the ongoing importance of wastewater genomic analyses towards understanding SARS-CoV-2 as it enters the endemic phase.

2.
Food Environ Virol ; 14(4): 410-416, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35982363

RESUMEN

This study aimed to develop a framework for combining community wastewater surveillance with state clinical surveillance for the confirmation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants within the community and to provide recommendations on how to expand on such research and apply the findings in public health responses. Wastewater samples were collected weekly from 17 geographically resolved locations in Louisville/Jefferson County, Kentucky (USA), from February 10 to December 13, 2021. Genomic surveillance and quantitative reverse transcription PCR (RT-qPCR) platforms were used to screen for SARS-CoV-2 in wastewater, and state clinical surveillance was used for confirmation. The study results highlighted an increased epidemiological value of combining community wastewater genomic surveillance and RT-qPCR with conventional case-auditing methods. The spatial scale and temporal frequency of wastewater sampling provided promising sensitivity and specificity for gaining public health screening insights about SARS-CoV-2 emergence, seeding, and spread in communities. Improved national surveillance systems are needed against future pathogens and variants, and wastewater-based genomic surveillance exhibits great potential when coupled with clinical testing. This paper presents evidence that complementary wastewater and clinical testing are cost-effectively enhanced when used in combination, as they provide a strong tool for a joint public health framework. Future pathogens of interest may be examined in either a targeted fashion or using a more global approach where all pathogens are monitored. This study has also provided novel insights developed from evidence-based public health practices.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Aguas Residuales , COVID-19/epidemiología , Monitoreo Epidemiológico Basado en Aguas Residuales , Genómica , Práctica de Salud Pública
3.
Matrix Biol ; 109: 49-69, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35346795

RESUMEN

The cardiac extracellular matrix plays essential roles in homeostasis and injury responses. Although the role of fibrillar collagens have been thoroughly documented, the functions of non-fibrillar collagen members remain underexplored. These include a distinct group of non-fibrillar collagens, termed, fibril-associated collagens with interrupted triple helices (FACITs). Recent reports of collagen type XIX (encoded by Col19a1) expression in adult heart and evidence of its enhanced expression in cardiac ischemia suggest important functions for this FACIT in cardiac ECM structure and function. Here, we examined the cellular source of collagen XIX in the adult murine heart and evaluated its involvement in ECM structure and ventricular function. Immunodetection of collagen XIX in fractionated cardiovascular cell lineages revealed fibroblasts and smooth muscle cells as the primary sources of collagen XIX in the heart. Based on echocardiographic and histologic analyses, Col19a1 null (Col19a1N/N) mice exhibited reduced systolic function, thinning of left ventricular walls, and increased cardiomyocyte cross-sectional areas-without gross changes in myocardial collagen content or basement membrane morphology. Col19a1N/N cardiac fibroblasts had augmented expression of several enzymes involved in the synthesis and stability of fibrillar collagens, including PLOD1 and LOX. Furthermore, second harmonic generation-imaged ECM derived from Col19a1N/N cardiac fibroblasts, and transmission electron micrographs of decellularized hearts from Col19a1N/N null animals, showed marked reductions in fibrillar collagen structural organization. Col19a1N/N mice also displayed enhanced phosphorylation of focal adhesion kinase (FAK), signifying de-repression of the FAK pathway-a critical mediator of cardiomyocyte hypertrophy. Collectively, we show that collagen XIX, which had a heretofore unknown role in the mammalian heart, participates in the regulation of cardiac structure and function-potentially through modulation of ECM fibrillar collagen structural organization. Further, these data suggest that this FACIT may modify ECM superstructure via acting at the level of the fibroblast to regulate their expression of collagen synthetic and stabilization enzymes.


Asunto(s)
Colágeno , Colágenos Asociados a Fibrillas , Animales , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Colágenos Asociados a Fibrillas/metabolismo , Colágenos Fibrilares/metabolismo , Mamíferos/metabolismo , Ratones , Función Ventricular
4.
Psychol Serv ; 19(1): 46-48, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32673035

RESUMEN

This article is a combined 1st-person narrative of a mental health professional with a mental illness, referred to as a prosumer, and her psychologist friend who stood by her during her 1st manic episode with psychosis. Challenges prosumers face are highlighted. These include stigma, questions about the impact of illness on ability to work in the field, and the choice of whether to disclose about the illness and to whom. Disclosures about lived experience within public settings, outside of the therapy room, are encouraged for several reasons. Visibility can reinforce recovery, promote understanding and accurate empathy, encourage help-seeking behavior, destigmatize mental illness, and reinforce the development of trustworthy and credible supports. This frank and detailed narrative provides an example of a psychologist with bipolar disorder who, with support and active treatment, bravely overcame a mental health crisis and returned to wellness and contribution to the mental health field. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Salud Mental , Trastornos Psicóticos , Femenino , Personal de Salud/psicología , Humanos , Estigma Social
5.
Chem Commun (Camb) ; 47(17): 5028-30, 2011 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-21445418

RESUMEN

Scrambling experiments suggest that the self-assembly of 2D ladders via imine metathesis is kinetically trapped at four or more rungs. Consequently, ladders containing five or more rungs cannot be synthesized in high yield under the conditions used, as misaligned out-of-register byproducts cannot self-correct.

6.
Pharmacogenomics ; 11(10): 1389-402, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21047202

RESUMEN

AIMS: Tacrolimus has a narrow therapeutic window and shows significant interindividual difference in dose requirement. In this study we aim to first identify genetic factors that impact tacrolimus dose using a candidate gene association approach, and then generate a personalized algorithm combining identified genetic and clinical factors to predict individualized tacrolimus dose. MATERIALS & METHODS: We screened 768 SNPs in 15 candidate genes in metabolism, transport and calcineurin inhibition pathways of tacrolimus, for association with tacrolimus dose in a discovery cohort of 96 patients. RESULTS: Four polymorphisms in CYP3A5 and one polymorphism in CYP3A4 were identified to be significantly associated with tacrolimus stable dose (p < 8.46 × 10(-5)). The same SNPs were identified when dose-normalized trough tacrolimus concentration was analyzed. The CYP3A5*1 allele was associated with significantly higher stable dose, bigger dose increase, higher risk of being underdosed and lower incidence of post-transplant hyperlipidemia. ABCB1 polymorphisms were not associated with stable dose. No significant difference was found between CYP3A5 expressers and nonexpressers in incidence of acute rejection and time to first rejection. Age, ethnicity and CYP3A inhibitor use could predict 30% of tacrolimus dosing variability. Adding the identified genetic polymorphisms to the algorithm increased the predictability to 58%. In two validation cohorts of 77 and 64 patients, the algorithm containing both genetic and clinical factors produced correlation coefficients of 0.63 and 0.42, respectively. This algorithm gave a prediction of the stable doses closer to the actual doses when compared with another algorithm based only on the CYP3A5 genotype. CONCLUSION: CYP3A5 genotype is the most significant genetic factor that impacts tacrolimus dose among the genes studied. This study generated the first pharmacogenomics model that predicts tacrolimus stable dose based on age, ethnicity, genotype and comedication use. Our results highlight the importance of incorporating both genetic and clinical, demographic factors into dose prediction.


Asunto(s)
Citocromo P-450 CYP3A/genética , Trasplante de Riñón/fisiología , Farmacogenética/métodos , Polimorfismo de Nucleótido Simple/genética , Tacrolimus/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Trasplante de Riñón/rehabilitación , Trasplante de Riñón/tendencias , Masculino , Persona de Mediana Edad , Farmacogenética/tendencias , Valor Predictivo de las Pruebas , Adulto Joven
7.
Expert Opin Drug Saf ; 8(4): 421-34, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19522662

RESUMEN

Sirolimus is an antiproliferative immunosuppressive agent that inhibits the mammalian target of rapamycin. It is highly effective in preventing acute renal allograft rejection and can be used with either calcineurin inhibitors, antimetabolites or corticosteroids. Early studies in renal transplantation have provided insight into optimal dosing strategies of sirolimus and of concomitant immunosuppressive agents. Familiarity with the adverse effect profile of sirolimus and pharmacokinetic and dynamic interactions with other immunosuppressive agents allows for earlier recognition and better management of sirolimus-related complications. The role of sirolimus in preserving long-term renal function, post-transplant malignancies and in prevention of atherosclerosis is currently being considered.


Asunto(s)
Inmunosupresores/uso terapéutico , Enfermedades Renales/prevención & control , Sirolimus/uso terapéutico , Ensayos Clínicos como Asunto , Ciclosporina/administración & dosificación , Quimioterapia Combinada , Rechazo de Injerto/prevención & control , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/farmacocinética , Trasplante de Riñón/efectos adversos , Periodo Posoperatorio , Sirolimus/administración & dosificación , Sirolimus/efectos adversos , Sirolimus/farmacocinética , Tacrolimus/administración & dosificación , Factores de Tiempo
9.
J Org Chem ; 71(14): 5282-90, 2006 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-16808517

RESUMEN

Both homo- and heterosequence m-phenylene ethynylene oligomers are synthesized using a conceptually simple iterative solid-phase strategy. Oligomers are attached to Merrifield's resin through a known triazene-type linkage. The phenylene ethynylene molecular backbone is constructed through a series of palladium-mediated cross-coupling reactions. The strategy employs two types of monomers that bear orthogonal reactivity, one being a monoprotected bisethynyl arene and the other being a 3-bromo-5-iodo arene. The catalyst conditions are tailored to the requirements of each monomer type. The monoprotected bisethynyl arene is coupled to the growing chain in 2 h at room temperature using a Pd(I) dimer precatalyst ((t)Bu3P(Pd(mu-Cl)(mu-2-methyl allyl)Pd)P(t)Bu3) in conjunction with ZnBr2 and diisopropylamine. In alternate steps, the resin is deprotected in situ with TBAF and coupled to the 3-bromo-5-iodo arene using the iodo selective Pd(tri-2-furylphosphine)4 catalyst in conjunction with CuI and piperidine; this reaction is also completed in 2 h at room temperature. These cross-coupling events are alternated until an oligomer of the desired length is achieved. The oligomer is then cleaved from the resin using CH(2)I(2)/I(2) at 110 degrees C and purified using preparatory GPC. Using this method, a series of homo- and heterosequence oligomers up to 12 units in length in excellent yield and purity were synthesized on the 100 mg scale. Longer oligomers were attempted; however, deletion sequences were found in oligomers longer than 12 units.

10.
J Neurosci ; 26(14): 3713-20, 2006 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-16597725

RESUMEN

A fundamental objective of anesthesia research is to identify the receptors and brain regions that mediate the various behavioral components of the anesthetic state, including amnesia, immobility, and unconsciousness. Using complementary in vivo and in vitro approaches, we found that GABAA receptors that contain the alpha5 subunit (alpha5GABAARs) play a critical role in amnesia caused by the prototypic intravenous anesthetic etomidate. Whole-cell recordings from hippocampal pyramidal neurons showed that etomidate markedly increased a tonic inhibitory conductance generated by alpha5GABAARs, whereas synaptic transmission was only slightly enhanced. Long-term potentiation (LTP) of field EPSPs recorded in CA1 stratum radiatum was reduced by etomidate in wild-type (WT) but not alpha5 null mutant (alpha5-/-) mice. In addition, etomidate impaired memory performance of WT but not alpha5-/- mice for spatial and nonspatial hippocampal-dependent learning tasks. The brain concentration of etomidate associated with memory impairment in vivo was comparable with that which increased the tonic inhibitory conductance and blocked LTP in vitro. The alpha5-/- mice did not exhibit a generalized resistance to etomidate, in that the sedative-hypnotic effects measured with the rotarod, loss of righting reflex, and spontaneous motor activity were similar in WT and alpha5-/- mice. Deletion of the alpha5 subunit of the GABAARs reduced the amnestic but not the sedative-hypnotic properties of etomidate. Thus, the amnestic and sedative-hypnotic properties of etomidate can be dissociated on the basis of GABAAR subtype pharmacology.


Asunto(s)
Etomidato/administración & dosificación , Hipnosis Anestésica/métodos , Potenciación a Largo Plazo/fisiología , Memoria/efectos de los fármacos , Memoria/fisiología , Células Piramidales/fisiología , Receptores de GABA-A/metabolismo , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Amnesia/inducido químicamente , Amnesia/metabolismo , Anestésicos Generales/administración & dosificación , Animales , Células Cultivadas , Hipnóticos y Sedantes/administración & dosificación , Potenciación a Largo Plazo/efectos de los fármacos , Ratones , Células Piramidales/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología
11.
J Am Chem Soc ; 127(8): 2666-76, 2005 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-15725024

RESUMEN

With the Fritsch-Buttenberg-Wiechell rearrangement as a primary synthetic route, a series of conjugated, triisopropylsilyl end-capped polyynes containing 2-10 acetylene units has been assembled. In a few steps, significant quantities of the polyynes are made available, which allow for a thorough analysis of their structural, physical, and optical properties. Molecules in the series have been characterized in detail using (13)C NMR spectroscopy, differential scanning calorimetry, mass spectrometry, and, for four derivatives including octayne 6, X-ray crystallography. UV-vis spectroscopy of the polyynes 1-7 shows a consistent lowering of the HOMO-LUMO gap (E(g)) as a function of the number of acetylene units (n), fitting a power-law relationship of E(g) approximately n(-)(0.379)(+/-)(0.002). The third-order nonlinear optical (NLO) properties of the polyyne series have been examined, and the nonresonant molecular second hyperpolarizabilities (gamma) increase as a function of length according to the power-law gamma approximately n(4.28)(+/-)(0.13). This result exhibits an exponent that is larger than theoretically predicted for polyynes and higher than is observed for polyenes and polyenynes. The combined linear and nonlinear optical results confirm recent theoretical studies that suggest polyynes as model 1-D conjugated systems. On the basis of UV-vis spectroscopic analysis, the effective conjugation length for this series of polyynes is estimated to be ca. n = 32, providing insight into characteristics of carbyne.

12.
Org Lett ; 7(1): 51-4, 2005 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-15624975

RESUMEN

A series of alpha,omega-diarylpolyynes has been synthesized. In addition to the synthesis of three hexaynes (3a-c), a notably improved synthesis of 1,16-diphenylhexadecaoctayne (5) is described. The third-order nonlinear optical characteristics for these molecules have been studied and show a substantial increase in molecular hyperpolarizability (gamma) as a function of increasing length. The unusual solid-state structures of compounds 3a and 3b are reported.

13.
J Neurosci ; 24(39): 8454-8, 2004 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-15456818

RESUMEN

Volatile (inhaled) anesthetics cause amnesia at concentrations well below those that cause loss of consciousness and immobility; however, the underlying neuronal mechanisms are unknown. Although many anesthetics increase inhibitory GABAergic synaptic transmission, this effect occurs only at high concentrations (>100 microm). Molecular targets for low concentrations of inhaled anesthetics have not been identified. Here, we report that a tonic inhibitory conductance in hippocampal pyramidal neurons generated by alpha5 subunit-containing GABA(A) receptors is highly sensitive to low concentrations of the volatile anesthetic isoflurane (ISO) (25 and 83.3 microm). The alpha5 subunit is necessary for enhancement of the tonic current by these low concentrations of isoflurane because potentiation is absent in neurons from alpha5-/- mice. Furthermore, ISO (25 microm) potentiated recombinant human alpha5beta3gamma2L GABA(A) receptors, whereas this effect was not seen with alpha1beta3gamma2L GABA(A) receptors. These studies suggest that an increased tonic inhibition in the hippocampus may contribute to amnestic properties of volatile anesthetics.


Asunto(s)
Anestésicos por Inhalación/farmacología , Hipocampo/efectos de los fármacos , Isoflurano/farmacología , Inhibición Neural/efectos de los fármacos , Receptores de GABA-A/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Animales , Células Cultivadas , Corteza Cerebral/citología , Relación Dosis-Respuesta a Droga , Potenciales Evocados/efectos de los fármacos , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Hipocampo/citología , Hipocampo/fisiología , Ratones , Ratones Noqueados , Células Piramidales/efectos de los fármacos , Células Piramidales/fisiología , Receptores de GABA-A/genética , Receptores de GABA-A/fisiología , Proteínas Recombinantes
14.
J Chem Phys ; 120(15): 6807-10, 2004 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15267578

RESUMEN

Polyynes represent a unique class of conjugated organic compounds. The third-order nonlinear optical response of polyynes has been extensively modeled theoretically, and it is generally believed that the increase in molecular second hyperpolarizability (gamma) as a function of length for polyynes should be lower than that for polyenes. Experimental evidence to test this prediction, however, has been absent. We have synthesized conjugated polyynes that contain up to 20 consecutive sp-hybridized carbons, and we have determined their nonresonant gamma-values as a function of the number of acetylene repeat units (n). These gamma-values demonstrate a power-law behavior versus n(gamma approximately n(4.28+/-0.13)), with an exponent that is both larger than theoretically predicted for polyynes and substantially higher than that observed for polyenes or polyenynes. Furthermore, no saturation of the linear or nonlinear optical properties is observed.

15.
Proc Natl Acad Sci U S A ; 101(10): 3662-7, 2004 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-14993607

RESUMEN

The principal inhibitory neurotransmitter in the mammalian brain, gamma-aminobutyric acid (GABA), is thought to regulate memory processes by activating transient inhibitory postsynaptic currents. Here we describe a nonsynaptic, tonic form of inhibition in mouse CA1 pyramidal neurons that is generated by a distinct subpopulation of GABA type A receptors (GABA(A)Rs). This tonic inhibitory conductance is predominantly mediated by alpha5 subunit-containing GABA(A)Rs (alpha5GABA(A)Rs) that have different pharmacological and kinetic properties compared to postsynaptic receptors. GABA(A)Rs that mediate the tonic conductance are well suited to detect low, persistent, ambient concentrations of GABA in the extracellular space because they are highly sensitive to GABA and desensitize slowly. Moreover, the tonic current is highly sensitive to enhancement by amnestic drugs. Given the restricted expression of alpha5GABA(A)Rs to the hippocampus and the association between reduced alpha5GABA(A)R function and improved memory performance in behavioral studies, our results suggest that tonic inhibition mediated by alpha5GABA(A)Rs in hippocampal pyramidal neurons plays a key role in cognitive processes.


Asunto(s)
Células Piramidales/fisiología , Receptores de GABA-A/fisiología , Animales , Línea Celular , Cognición/fisiología , Electrofisiología , Agonistas del GABA/farmacología , Humanos , Imidazoles/farmacología , Técnicas In Vitro , Memoria/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Conducción Nerviosa/efectos de los fármacos , Conducción Nerviosa/fisiología , Subunidades de Proteína , Células Piramidales/efectos de los fármacos , Piridinas/farmacología , Receptores de GABA-A/química , Receptores de GABA-A/deficiencia , Receptores de GABA-A/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transfección , Zolpidem
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...