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1.
J Org Chem ; 89(9): 6085-6099, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38648720

RESUMO

Herein, we disclose a facile synthetic strategy to access an important class of drug molecules that contain chiral 1,2-amino alcohol functionality utilizing highly effective ruthenium-catalyzed asymmetric transfer hydrogenation of unprotected α-ketoamines. Recently, the COVID-19 pandemic has caused a crisis of shortage of many important drugs, especially norepinephrine and epinephrine, for the treatment of anaphylaxis and hypotension because of the increased demand. Unfortunately, the existing technologies are not fulfilling the worldwide requirement due to the existing lengthy synthetic protocols that require additional protection and deprotection steps. We identified a facile synthetic protocol via a highly enantioselective one-step process for epinephrine and a two-step process for norepinephrine starting from unprotected α-ketoamines 1b and 1a, respectively. This newly developed enantioselective ruthenium-catalyzed asymmetric transfer hydrogenation was extended to the synthesis of many 1,2-amino alcohol-containing drug molecules such as phenylephrine, denopamine, norbudrine, and levisoprenaline, with enantioselectivities of >99% ee and high isolated yields.


Assuntos
Amino Álcoois , Rutênio , Hidrogenação , Catálise , Amino Álcoois/química , Amino Álcoois/síntese química , Rutênio/química , Estereoisomerismo , Estrutura Molecular , Aminas/química
2.
J Urol ; 205(4): 1126-1132, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33259269

RESUMO

PURPOSE: Benign prostatic hyperplasia is one of the most common conditions seen by a general urologist. Validated questionnaires provide insight into patient symptoms, however office based uroflow devices are limited by the variability of voiding behavior. Using a home uroflow device, we assessed individual voiding variability, temporal distribution of voiding parameters and the impact of age on voiding. MATERIALS AND METHODS: Between April 2019 and June 2020, 19,824 unique voiding profiles were captured using the Stream Dx Uroflowmeter and retrospectively analyzed. Age and number of voids were summarized by mean±standard deviation. We used mixed effects models to compare average values and intrapatient variability of voiding parameters to time of day and age. The coefficient of variation was used to assess intrapatient variability. RESULTS: A total of 637 patients were identified with 625 meeting inclusion criteria, producing 19,824 voids. Mean age was 67 (±10.2) years old, and each patient provided on average 5 (±3.3) voids a day through 7 days. Average intrapatient voiding parameters showed notable variability, where the coefficient of variation for maximum flow was 27.6% (95% CI 26.6-28.6). Early morning voids were associated with higher volume and lower number of voids. As age progressed, voiding profiles worsened in a linear fashion. Afternoon and evening voids were associated with reduced intrapatient variability relative to early morning voids. CONCLUSIONS: Assessment of 19,824 uroflows using an accurate and precise home uroflow device demonstrates that an individual's voiding parameters vary greatly from day to day, throughout the day, and worsen with age. Multiple measurements performed at home provides a more realistic assessment of true voiding behavior by capturing individual voiding variability and can help urologists make better decisions in patient care.


Assuntos
Hiperplasia Prostática/complicações , Hiperplasia Prostática/fisiopatologia , Transtornos Urinários/etiologia , Transtornos Urinários/fisiopatologia , Urodinâmica , Idoso , Humanos , Masculino , Estudos Retrospectivos , Autocuidado
3.
Environ Microbiol ; 22(6): 2346-2364, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32250010

RESUMO

Microbial reduction of soluble selenium (Se) or tellurium (Te) species results in immobilization as elemental forms and this process has been employed in soil bioremediation. However, little is known of direct and indirect fungal interactions with Se-/Te-bearing ores. In this research, the ability of Phoma glomerata to effect transformation of selenite and tellurite was investigated including interaction with Se and Te present in sulfide ores from the Kisgruva Proterozoic volcanogenic deposit. Phoma glomerata could precipitate elemental Se and Te as nanoparticles, intracellularly and extracellularly, when grown with selenite or tellurite. The nanoparticles possessed various surface capping molecules, with formation being influenced by extracellular polymeric substances. The presence of sulfide ore also affected the production of exopolysaccharide and protein. Although differences were undetectable in gross Se and Te ore levels before and after fungal interaction using X-ray fluorescence, laser ablation inductively coupled plasma mass spectrometry of polished flat ore surfaces revealed that P. glomerata could effect changes in Se/Te distribution and concentration indicating Se/Te enrichment in the biomass. These findings provide further understanding of fungal roles in metalloid transformations and are relevant to the geomicrobiology of environmental metalloid cycling as well as informing applied approaches for Se and Te immobilization, biorecovery or bioremediation.


Assuntos
Phoma/metabolismo , Selênio/metabolismo , Telúrio/metabolismo , Biodegradação Ambiental , Biotransformação , Nanopartículas , Sulfetos , Erupções Vulcânicas
4.
Oecologia ; 190(3): 679-688, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31250186

RESUMO

Root hemiparasites acquire resources from neighboring plants' vascular systems and can limit host growth, depress community productivity, and exert keystone effects. The strength of these effects is posited to be greater where hosts are nutrient-stressed but studies of annual hemiparasites show effects to be short-lived and variable. We conducted a 10-year experiment testing whether fertilizer addition alters the impact of the clonal, perennial hemiparasite Pedicularis canadensis on a prairie community and examine whether short-term trends reflect longer-term effects on community dynamics. Hemiparasite removal in 1-m2 plots increased productivity over the first three field seasons, but later the difference between removal and non-removal plots diminished as P. canadensis disappeared from 24 of the 48 non-removal plots. Effects of hemiparasite removal were context independent relative to fertilizer and shade treatments, but fertilizer initially increased, and then subsequently suppressed P. canadensis biomass. In non-removal plots, hemiparasite biomass was negatively associated with total community dry mass, which was greater in fertilized plots. Initially, fertilizer promoted graminoids, but after seven more field seasons, non-legume forbs responded most strongly. Measures of biodiversity tended to increase with hemiparasite cover. Demographic data collected at two different times for P. canadensis show high survivorship of established plants, high seed input, with seedling survival greater in taller vegetation. Unlike annual hemiparasite populations, well-established P. canadensis buffer populations against large demographic swings. At the scale of a few square meters, this keystone species produces significant heterogeneity in a prairie, but its presence at that scale is transient over approximately one decade.


Assuntos
Pradaria , Pedicularis , Biodiversidade , Biomassa , Plantas
5.
Bioconjug Chem ; 29(6): 1859-1865, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29893553

RESUMO

An efficient multicomponent orthogonal protocol was developed for post-synthetic oligonucleotide modification using commercially available 2'- O-methyl ester and 2'- O-propargyl nucleoside scaffolds. Amidation of methyl esters with primary amines was achieved in the presence of 2'-propargyl groups which were utilized for subsequent copper catalyzed cycloaddition with GalNAc-azide. The methodology was applied to generate siRNA composed of multiple amide and triazole conjugates. Computational methods were used to illustrate the impact of substitution at the 2'-position. This a powerful post-oligomerization technique for rapidly introducing diversity to oligonucleotide design.


Assuntos
Acetilgalactosamina/química , Amidas/química , Azidas/química , Cobre/química , Reação de Cicloadição/métodos , Oligonucleotídeos/química , RNA Interferente Pequeno/química , Acetilgalactosamina/síntese química , Amidas/síntese química , Azidas/síntese química , Catálise , Química Click/métodos , Esterificação , Células HeLa , Humanos , Modelos Moleculares , Oligonucleotídeos/síntese química , RNA Interferente Pequeno/síntese química , Triazóis/síntese química , Triazóis/química
6.
Curr Urol Rep ; 19(8): 58, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29808325

RESUMO

PURPOSE OF REVIEW: Male factor infertility is a complex and multifaceted problem facing the modern urologist and is identified in 30-40% of infertile couples. This review focuses on the use of ultrasound, as an adjunct screening tool, in the initial evaluation of male infertility. RECENT FINDINGS: Access to male reproductive urologist for assessment of male infertility is limited and about a quarter of infertile couples do not complete the male component in their infertility assessment. Ultrasound evaluation of the infertile male is low-cost and non-invasive and helps uncover underlying pathologies that may be missed during the initial assessment. The addition of ultrasound allows the physician to accurately assess testicular anatomy and dimensions, as well as vascular environments, which may help guide treatment decisions. Scrotal ultrasound evaluation, in conjunction with a semen analysis and as an adjunct to physical exam, can be offered in the initial assessment of men who present for infertility consultation given its low cost, non-invasive nature, and ability to detect and discriminate between various etiologies of male infertility. Further, when directed by physical exam and semen analysis findings, it provides a valuable tool to select men for referral to a reproductive urologist, especially for infertile couples who are only screened by reproductive endocrinologists and female infertility specialists.


Assuntos
Doenças dos Genitais Masculinos/diagnóstico por imagem , Infertilidade Masculina/diagnóstico por imagem , Escroto/diagnóstico por imagem , Testículo/diagnóstico por imagem , Análise Custo-Benefício , Humanos , Masculino , Programas de Rastreamento , Tamanho do Órgão , Análise do Sêmen , Testículo/irrigação sanguínea , Ultrassonografia/economia , Resistência Vascular
7.
Med Educ ; 51(7): 708-717, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28418106

RESUMO

BACKGROUND: Barriers hinder medical students from reporting breaches in professional behaviour, which can adversely impact institutional culture. No studies have reported student perspectives on how to address these barriers successfully. Our study (i) evaluated the likelihood of reporting based on violation severity, (ii) assessed barriers to reporting and (iii) elicited students' proposed solutions. METHODS: Four medical students designed a cross-sectional study in 2015. In response to seven scenarios, students rated the likelihood of reporting the violation, indicated perceived barriers and identified solutions. Additional questions investigated the perceived importance of professionalism, confidence in understanding professionalism and trust in administrative protection from negative consequences. RESULTS: Two hundred and seventy-two students in their clinical years (MS2-4) responded to the survey (RR = 50%). Students were 70-90% likely to report major violations, but < 30% likely to report minor or moderate violations. Barriers included concerns about an uncomfortable relationship (41%), potential negative repercussions on grades or opportunities (23%), and addressing by direct discussion rather than reporting (23%). Solutions included simplified reporting, control over report release date, improved feedback to reporters, training for real-time resolution of concerns and a neutral resource to help students triage concerns. No differences existed between classes regarding the importance or understanding of professionalism. In linear regression, only importance of professionalism predicted likelihood of reporting and this did not change with training. CONCLUSIONS: Hindered by common barriers, students are unlikely to report a violation unless it is a serious breach of professionalism. Student-derived solutions should be explored by medical school administrators to encourage reporting of violation of professionalism.


Assuntos
Ética Profissional , Má Conduta Profissional , Estudantes de Medicina , Estudos Transversais , Retroalimentação , Humanos , Faculdades de Medicina , Inquéritos e Questionários
10.
bioRxiv ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38895202

RESUMO

URA3 is frequently used in the yeast community as the mutation target for 5-fluoroorotic acid (5-FOA) resistance. We identified a novel class of ura6 mutants that can grow in the presence of 5-FOA. Unlike ura3 mutants, ura6 mutants remain prototrophic and grow in the absence of uracil. In addition to 5-FOA resistance, we found that mutations to URA6 also confer resistance to 5-fluorocytosine (5-FC) and 5-fluorouracil (5-FU). In total, we identified 50 unique missense mutations across 32 residues of URA6. We found that 28 out of the 32 affected residues are located in regions conserved between Saccharomyces cerevisiae and three clinically relevant pathogenic fungi. These findings suggest that mutations to URA6 present a second target for mutation screens utilizing 5-FOA as a selection marker as well as a potential mode of resistance to the antifungal therapeutic 5-FC.

11.
G3 (Bethesda) ; 14(3)2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38135291

RESUMO

Studying the genetic and molecular characteristics of brewing yeast strains is crucial for understanding their domestication history and adaptations accumulated over time in fermentation environments, and for guiding optimizations to the brewing process itself. Saccharomyces cerevisiae (brewing yeast) is among the most profiled organisms on the planet, yet the temporal molecular changes that underlie industrial fermentation and beer brewing remain understudied. Here, we characterized the genomic makeup of a Saccharomyces cerevisiae ale yeast widely used in the production of Hefeweizen beers, and applied shotgun mass spectrometry to systematically measure the proteomic changes throughout 2 fermentation cycles which were separated by 14 rounds of serial repitching. The resulting brewing yeast proteomics resource includes 64,740 protein abundance measurements. We found that this strain possesses typical genetic characteristics of Saccharomyces cerevisiae ale strains and displayed progressive shifts in molecular processes during fermentation based on protein abundance changes. We observed protein abundance differences between early fermentation batches compared to those separated by 14 rounds of serial repitching. The observed abundance differences occurred mainly in proteins involved in the metabolism of ergosterol and isobutyraldehyde. Our systematic profiling serves as a starting point for deeper characterization of how the yeast proteome changes during commercial fermentations and additionally serves as a resource to guide fermentation protocols, strain handling, and engineering practices in commercial brewing and fermentation environments. Finally, we created a web interface (https://brewing-yeast-proteomics.ccbb.utexas.edu/) to serve as a valuable resource for yeast geneticists, brewers, and biochemists to provide insights into the global trends underlying commercial beer production.


Assuntos
Proteômica , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fermentação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Cerveja/análise
12.
Org Lett ; 26(14): 2751-2757, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37486800

RESUMO

We report a new class of highly effective, benzooxaphosphole-based, water-soluble ligands in the application of Suzuki-Miyaura cross-coupling reactions for sterically hindered substrates in aqueous media. The catalytic activities of the coupling reactions were greatly enhanced by the addition of catalytic amounts of organic phase transfer reagents, such as tetraglyme and tetrabutylammonium bromide. The optimized general protocol can be conducted with a low catalyst load, thereby providing a practical solution for these reactions. The viability of this new Suzuki-Miyaura protocol was demonstrated with various substrates to generate important building blocks, including heterocycles, for the synthesis of biologically active compounds.

13.
Geobiology ; 21(1): 28-43, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36168296

RESUMO

Manganese (Mn) oxidation in marine environments requires oxygen (O2 ) or other reactive oxygen species in the water column, and widespread Mn oxide deposition in ancient sedimentary rocks has long been used as a proxy for oxidation. The oxygenation of Earth's atmosphere and oceans across the Archean-Proterozoic boundary are associated with massive Mn deposits, whereas the interval from 1.8-1.0 Ga is generally believed to be a time of low atmospheric oxygen with an apparent hiatus in sedimentary Mn deposition. Here, we report geochemical and mineralogical analyses from 1.1 Ga manganiferous marine-shelf siltstones from the Bangemall Supergroup, Western Australia, which underlie recently discovered economically significant manganese deposits. Layers bearing Mn carbonate microspheres, comparable with major global Mn deposits, reveal that intense periods of sedimentary Mn deposition occurred in the late Mesoproterozoic. Iron geochemical data suggest anoxic-ferruginous seafloor conditions at the onset of Mn deposition, followed by oxic conditions in the water column as Mn deposition persisted and eventually ceased. These data imply there was spatially widespread surface oxygenation ~1.1 Ga with sufficiently oxic conditions in shelf environments to oxidize marine Mn(II). Comparable large stratiform Mn carbonate deposits also occur in ~1.4 Ga marine siltstones hosted in underlying sedimentary units. These deposits are greater or at least commensurate in scale (tonnage) to those that followed the major oxygenation transitions from the Neoproterozoic. Such a period of sedimentary manganogenesis is inconsistent with a model of persistently low O2 throughout the entirety of the Mesoproterozoic and provides robust evidence for dynamic redox changes in the mid to late Mesoproterozoic.


Assuntos
Sedimentos Geológicos , Água do Mar , Sedimentos Geológicos/análise , Manganês , Carbonatos/análise , Oxirredução , Oxigênio/análise , Água
14.
bioRxiv ; 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37790497

RESUMO

Studying the genetic and molecular characteristics of brewing yeast strains is crucial for understanding their domestication history and adaptations accumulated over time in fermentation environments, and for guiding optimizations to the brewing process itself. Saccharomyces cerevisiae (brewing yeast) is amongst the most profiled organisms on the planet, yet the temporal molecular changes that underlie industrial fermentation and beer brewing remain understudied. Here, we characterized the genomic makeup of a Saccharomyces cerevisiae ale yeast widely used in the production of Hefeweizen beers, and applied shotgun mass spectrometry to systematically measure the proteomic changes throughout two fermentation cycles which were separated by 14 rounds of serial repitching. The resulting brewing yeast proteomics resource includes 64,740 protein abundance measurements. We found that this strain possesses typical genetic characteristics of Saccharomyces cerevisiae ale strains and displayed progressive shifts in molecular processes during fermentation based on protein abundance changes. We observed protein abundance differences between early fermentation batches compared to those separated by 14 rounds of serial repitching. The observed abundance differences occurred mainly in proteins involved in the metabolism of ergosterol and isobutyraldehyde. Our systematic profiling serves as a starting point for deeper characterization of how the yeast proteome changes during commercial fermentations and additionally serves as a resource to guide fermentation protocols, strain handling, and engineering practices in commercial brewing and fermentation environments. Finally, we created a web interface (https://brewing-yeast-proteomics.ccbb.utexas.edu/) to serve as a valuable resource for yeast geneticists, brewers, and biochemists to provide insights into the global trends underlying commercial beer production.

15.
Oecologia ; 169(3): 783-92, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22215230

RESUMO

Hemiparasitic plants tend to thrive in and significantly affect plant communities in low-nutrient, high-light environments. Hemiparasites are assumed to be weak competitors for light but strong parasites, leading to the prediction that effects on hosts and communities should be a function of resource supply. We investigated the effects of light and mineral nutrients on hemiparasite-host relations in two experiments. Removal of the hemiparasite, addition of fertilizer, and full sun significantly increased total aboveground dry mass in small plots on a restored tallgrass prairie. After 3 years, removal of Pedicularis canadensis almost doubled the mass of grasses and had smaller effects on forb species, but the impact of the parasite was independent of resource level. Fertilizer increased grass growth only in full sun, increased non-legume forb growth only when shade was applied, and tended to depress legume growth when shaded. Light manipulation did not affect the hemiparasite across 4 years of manipulation but fertilizer increased P. canadensis shoot mass. A complementary greenhouse experiment with Andropogon gerardii as host produced qualitatively similar effects and showed that shade reduced root growth of both the host and the parasite. These results do not support common assumptions regarding hemiparasite-host relations under field conditions but indicate that a small hemiparasite can significantly affect prairie productivity regardless of resource supply.


Assuntos
Andropogon/parasitologia , Ecossistema , Interações Hospedeiro-Parasita , Pedicularis/fisiologia , Poaceae/parasitologia , Andropogon/crescimento & desenvolvimento , Fertilizantes , Illinois , Poaceae/crescimento & desenvolvimento , Luz Solar
16.
Zoonoses Public Health ; 69(7): 888-895, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35799333

RESUMO

Interactions between humans and pets are increasingly valued in western countries, leading to more extensive contact between humans and their pets within households. Although the magnitude of the risk of transfer of Escherichia coli between humans and their companion animals is undefined, that such transmission occurs has been established and warrants attention. This study examined 186 fresh faecal samples from companion dogs visiting 22 municipal dog parks in the Minneapolis/Saint Paul metropolitan area, Minnesota, USA. Samples were processed to isolate 3rd-generation cephalosporin-resistant E. coli, which were further characterized using PCR-based virulence genotyping, antimicrobial susceptibility profiling and whole-genome sequencing. Of the 186 faecal samples, 29% yielded cephalosporin-resistant E. coli, and 2.2% yielded extended-spectrum beta-lactamase producers. Co-resistance to sulfonamides was typical (77.3% of isolates), and multidrug resistance (i.e. to ≥3 antimicrobial classes), including to combinations of tetracyclines, phenicols, quinolones and aminoglycosides, was substantial (18.9% of isolates). Identified beta-lactamase genes included blaCMY-2 , blaTEM-1B , blaTEM-1 , blaCTX-M-24 , blaCTX-M-15 and blaOXA-1 . Genome sequencing of 14 isolates identified genes typical of extraintestinal pathogenic E. coli or enteropathogenic E. coli. In three instances, closely related isolates were recovered from different dogs, within either the same park-suggesting transfer of E. coli between dogs within the park-or different parks-suggesting that dogs may be pre-disposed to carry certain E. coli types, such as those from serogroups O4, O71 and O157. This study adds to the existing evidence that companion dogs can harbour and share antimicrobial-resistant E. coli with presumed intestinal or extraintestinal pathogenic potential.


Assuntos
Doenças do Cão , Escherichia coli Enteropatogênica , Infecções por Escherichia coli , Quinolonas , Aminoglicosídeos , Animais , Antibacterianos/farmacologia , Cefalosporinas , Doenças do Cão/epidemiologia , Cães , Escherichia coli Enteropatogênica/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Fezes , Humanos , Minnesota/epidemiologia , Animais de Estimação , Sulfonamidas , Tetraciclinas , beta-Lactamases/genética
17.
Org Process Res Dev ; 26(1): 82-90, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35095258

RESUMO

Pyrrolo[2,1-f][1,2,4]triazine (1) is an important regulatory starting material in the production of the antiviral drug remdesivir. Compound 1 was produced through a newly developed synthetic methodology utilizing simple building blocks such as pyrrole, chloramine, and formamidine acetate by examining the mechanistic pathway for the process optimization exercise. Triazine 1 was obtained in 55% overall yield in a two-vessel-operated process. This work describes the safety of the process, impurity profiles and control, and efforts toward the scale-up of triazine for the preparation of kilogram quantity.

18.
Ann Bot ; 108(5): 835-45, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21821626

RESUMO

Background and Aims Anaxagorea is the phylogenetically basalmost genus in the large tropical Annonaceae (custard apple family) of Magnoliales, but its floral structure is unknown in many respects. The aim of this study is to analyse evolutionarily interesting floral features in comparison with other genera of the Annonaceae and the sister family Eupomatiaceae. Methods Live flowers of Anaxagorea crassipetala were examined in the field with vital staining, liquid-fixed material was studied with scanning electron microscopy, and microtome section series were studied with light microscopy. In addition, herbarium material of two other Anaxagorea species was cursorily studied with the dissecting microscope. Key Results Floral phyllotaxis in Anaxagorea is regularly whorled (with complex whorls) as in all other Annonaceae with a low or medium number of floral organs studied so far (in those with numerous stamens and carpels, phyllotaxis becoming irregular in the androecium and gynoecium). The carpels are completely plicate as in almost all other Annonaceae. In these features Anaxagorea differs sharply from the sister family Eupomatiaceae, which has spiral floral phyllotaxis and ascidiate carpels. Flat stamens and the presence of inner staminodes differ from most other Annonaceae and may be plesiomorphic in Anaxagorea. However, the inner staminodes appear to be non-secretory in most Anaxagorea species, which differs from inner staminodes in other families of Magnoliales (Eupomatiaceae, Degeneriacae, Himantandraceae), which are secretory. Conclusions Floral phyllotaxis in Anaxagorea shows that there is no signature of a basal spiral pattern in Annonaceae and that complex whorls are an apomorphy not just for a part of the family but for the family in its entirety, and irregular phyllotaxis is derived. This and the presence of completely plicate carpels in Anaxagorea makes the family homogeneous and distinguishes it from the closest relatives in Magnoliales.


Assuntos
Annonaceae/anatomia & histologia , Annonaceae/crescimento & desenvolvimento , Flores/anatomia & histologia , Flores/crescimento & desenvolvimento , Annonaceae/ultraestrutura , Movimento Celular/fisiologia , Costa Rica , Flores/genética , Flores/ultraestrutura
19.
ACS Omega ; 6(15): 10396-10402, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-34056192

RESUMO

Molnupiravir (MK-4482, EIDD-2801) is a promising orally bioavailable drug candidate for the treatment of COVID-19. Herein, we describe a supply-centered and chromatography-free synthesis of molnupiravir from cytidine, consisting of two steps: a selective enzymatic acylation followed by transamination to yield the final drug product. Both steps have been successfully performed on a decagram scale: the first step at 200 g and the second step at 80 g. Overall, molnupiravir has been obtained in a 41% overall isolated yield compared to a maximum 17% isolated yield in the patented route. This route provides many advantages to the initial route described in the patent literature and would decrease the cost of this pharmaceutical should it prove safe and efficacious in ongoing clinical trials.

20.
Urology ; 139: 168-170, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32057790

RESUMO

Turner syndrome is a chromosomal disorder that occurs in an estimated 1 in 2500 female live births. It is estimated that 6%-12% of all Turner syndrome patients will be a mosaic with Y-chromosomal elements putting them at risk for gonadoblastoma and subsequent dysgerminoma. While 30%-50% of this population demonstrate gonadoblastoma, we only found 23 reported cases of dysgerminoma in the literature, and no reported cases of seminoma. We present the first case of seminoma in a phenotypic Turner 15-year-old female after prophylactic gonadectomy.


Assuntos
Castração/métodos , Gonadoblastoma , Hipogonadismo , Seminoma , Síndrome de Turner , Adolescente , Cromossomos Humanos Y/genética , Feminino , Gonadoblastoma/patologia , Gonadoblastoma/cirurgia , Terapia de Reposição Hormonal/métodos , Humanos , Hipogonadismo/diagnóstico , Hipogonadismo/terapia , Mosaicismo , Estadiamento de Neoplasias/métodos , Procedimentos Cirúrgicos Profiláticos/métodos , Risco Ajustado/métodos , Seminoma/patologia , Seminoma/cirurgia , Síndrome de Turner/diagnóstico , Síndrome de Turner/genética , Síndrome de Turner/fisiopatologia , Síndrome de Turner/terapia , Conduta Expectante
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