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1.
Cell ; 186(9): 1950-1967.e25, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36996814

RESUMO

Little is known about the critical metabolic changes that neural cells have to undergo during development and how temporary shifts in this program can influence brain circuitries and behavior. Inspired by the discovery that mutations in SLC7A5, a transporter of metabolically essential large neutral amino acids (LNAAs), lead to autism, we employed metabolomic profiling to study the metabolic states of the cerebral cortex across different developmental stages. We found that the forebrain undergoes significant metabolic remodeling throughout development, with certain groups of metabolites showing stage-specific changes, but what are the consequences of perturbing this metabolic program? By manipulating Slc7a5 expression in neural cells, we found that the metabolism of LNAAs and lipids are interconnected in the cortex. Deletion of Slc7a5 in neurons affects the postnatal metabolic state, leading to a shift in lipid metabolism. Additionally, it causes stage- and cell-type-specific alterations in neuronal activity patterns, resulting in a long-term circuit dysfunction.


Assuntos
Aminoácidos Neutros , Transportador 1 de Aminoácidos Neutros Grandes , Feminino , Humanos , Gravidez , Aminoácidos Neutros/genética , Aminoácidos Neutros/metabolismo , Encéfalo/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/genética , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Mutação , Neurônios/metabolismo , Animais , Camundongos
2.
Cell ; 168(1-2): 86-100.e15, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-27916275

RESUMO

Type 1 diabetes is characterized by the destruction of pancreatic ß cells, and generating new insulin-producing cells from other cell types is a major aim of regenerative medicine. One promising approach is transdifferentiation of developmentally related pancreatic cell types, including glucagon-producing α cells. In a genetic model, loss of the master regulatory transcription factor Arx is sufficient to induce the conversion of α cells to functional ß-like cells. Here, we identify artemisinins as small molecules that functionally repress Arx by causing its translocation to the cytoplasm. We show that the protein gephyrin is the mammalian target of these antimalarial drugs and that the mechanism of action of these molecules depends on the enhancement of GABAA receptor signaling. Our results in zebrafish, rodents, and primary human pancreatic islets identify gephyrin as a druggable target for the regeneration of pancreatic ß cell mass from α cells.


Assuntos
Artemisininas/farmacologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Modelos Animais de Doenças , Receptores de GABA-A/metabolismo , Transdução de Sinais , Animais , Artemeter , Artemisininas/administração & dosagem , Proteínas de Transporte/metabolismo , Transdiferenciação Celular/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus Tipo 1/patologia , Perfilação da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Insulina/genética , Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Camundongos , Estabilidade Proteica/efeitos dos fármacos , Ratos , Análise de Célula Única , Fatores de Transcrição/metabolismo , Peixe-Zebra , Ácido gama-Aminobutírico/metabolismo
3.
N Engl J Med ; 390(7): 611-622, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354140

RESUMO

BACKGROUND: Carbapenem-resistant Enterobacterales species and multidrug-resistant Pseudomonas aeruginosa are global health threats. Cefepime-taniborbactam is an investigational ß-lactam and ß-lactamase inhibitor combination with activity against Enterobacterales species and P. aeruginosa expressing serine and metallo-ß-lactamases. METHODS: In this phase 3, double-blind, randomized trial, we assigned hospitalized adults with complicated urinary tract infection (UTI), including acute pyelonephritis, in a 2:1 ratio to receive intravenous cefepime-taniborbactam (2.5 g) or meropenem (1 g) every 8 hours for 7 days; this duration could be extended up to 14 days in case of bacteremia. The primary outcome was both microbiologic and clinical success (composite success) on trial days 19 to 23 in the microbiologic intention-to-treat (microITT) population (patients who had a qualifying gram-negative pathogen against which both study drugs were active). A prespecified superiority analysis of the primary outcome was performed after confirmation of noninferiority. RESULTS: Of the 661 patients who underwent randomization, 436 (66.0%) were included in the microITT population. The mean age of the patients was 56.2 years, and 38.1% were 65 years of age or older. In the microITT population, 57.8% of the patients had complicated UTI, 42.2% had acute pyelonephritis, and 13.1% had bacteremia. Composite success occurred in 207 of 293 patients (70.6%) in the cefepime-taniborbactam group and in 83 of 143 patients (58.0%) in the meropenem group. Cefepime-taniborbactam was superior to meropenem regarding the primary outcome (treatment difference, 12.6 percentage points; 95% confidence interval, 3.1 to 22.2; P = 0.009). Differences in treatment response were sustained at late follow-up (trial days 28 to 35), when cefepime-taniborbactam had higher composite success and clinical success. Adverse events occurred in 35.5% and 29.0% of patients in the cefepime-taniborbactam group and the meropenem group, respectively, with headache, diarrhea, constipation, hypertension, and nausea the most frequently reported; the frequency of serious adverse events was similar in the two groups. CONCLUSIONS: Cefepime-taniborbactam was superior to meropenem for the treatment of complicated UTI that included acute pyelonephritis, with a safety profile similar to that of meropenem. (Funded by Venatorx Pharmaceuticals and others; CERTAIN-1 ClinicalTrials.gov number, NCT03840148.).


Assuntos
Antibacterianos , Ácidos Borínicos , Ácidos Carboxílicos , Cefepima , Meropeném , Infecções Urinárias , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Administração Intravenosa , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , beta-Lactamases/administração & dosagem , beta-Lactamases/efeitos adversos , beta-Lactamases/uso terapêutico , Ácidos Borínicos/administração & dosagem , Ácidos Borínicos/efeitos adversos , Ácidos Borínicos/uso terapêutico , Ácidos Carboxílicos/administração & dosagem , Ácidos Carboxílicos/efeitos adversos , Ácidos Carboxílicos/uso terapêutico , Cefepima/administração & dosagem , Cefepima/efeitos adversos , Cefepima/uso terapêutico , Quimioterapia Combinada , Hospitalização , Meropeném/administração & dosagem , Meropeném/efeitos adversos , Meropeném/uso terapêutico , Testes de Sensibilidade Microbiana , Pielonefrite/tratamento farmacológico , Pielonefrite/microbiologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia , Farmacorresistência Bacteriana
4.
N Engl J Med ; 391(2): 109-121, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38785209

RESUMO

BACKGROUND: Patients with type 2 diabetes and chronic kidney disease are at high risk for kidney failure, cardiovascular events, and death. Whether treatment with semaglutide would mitigate these risks is unknown. METHODS: We randomly assigned patients with type 2 diabetes and chronic kidney disease (defined by an estimated glomerular filtration rate [eGFR] of 50 to 75 ml per minute per 1.73 m2 of body-surface area and a urinary albumin-to-creatinine ratio [with albumin measured in milligrams and creatinine measured in grams] of >300 and <5000 or an eGFR of 25 to <50 ml per minute per 1.73 m2 and a urinary albumin-to-creatinine ratio of >100 and <5000) to receive subcutaneous semaglutide at a dose of 1.0 mg weekly or placebo. The primary outcome was major kidney disease events, a composite of the onset of kidney failure (dialysis, transplantation, or an eGFR of <15 ml per minute per 1.73 m2), at least a 50% reduction in the eGFR from baseline, or death from kidney-related or cardiovascular causes. Prespecified confirmatory secondary outcomes were tested hierarchically. RESULTS: Among the 3533 participants who underwent randomization (1767 in the semaglutide group and 1766 in the placebo group), median follow-up was 3.4 years, after early trial cessation was recommended at a prespecified interim analysis. The risk of a primary-outcome event was 24% lower in the semaglutide group than in the placebo group (331 vs. 410 first events; hazard ratio, 0.76; 95% confidence interval [CI], 0.66 to 0.88; P = 0.0003). Results were similar for a composite of the kidney-specific components of the primary outcome (hazard ratio, 0.79; 95% CI, 0.66 to 0.94) and for death from cardiovascular causes (hazard ratio, 0.71; 95% CI, 0.56 to 0.89). The results for all confirmatory secondary outcomes favored semaglutide: the mean annual eGFR slope was less steep (indicating a slower decrease) by 1.16 ml per minute per 1.73 m2 in the semaglutide group (P<0.001), the risk of major cardiovascular events 18% lower (hazard ratio, 0.82; 95% CI, 0.68 to 0.98; P = 0.029), and the risk of death from any cause 20% lower (hazard ratio, 0.80; 95% CI, 0.67 to 0.95, P = 0.01). Serious adverse events were reported in a lower percentage of participants in the semaglutide group than in the placebo group (49.6% vs. 53.8%). CONCLUSIONS: Semaglutide reduced the risk of clinically important kidney outcomes and death from cardiovascular causes in patients with type 2 diabetes and chronic kidney disease. (Funded by Novo Nordisk; FLOW ClinicalTrials.gov number, NCT03819153.).


Assuntos
Diabetes Mellitus Tipo 2 , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon , Hipoglicemiantes , Insuficiência Renal Crônica , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/mortalidade , Método Duplo-Cego , Taxa de Filtração Glomerular/efeitos dos fármacos , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Peptídeos Semelhantes ao Glucagon/farmacologia , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Injeções Subcutâneas , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/mortalidade , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/efeitos adversos , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon/uso terapêutico
5.
Cell ; 150(5): 948-60, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22939622

RESUMO

Heterochromatin serves important functions, protecting genome integrity and stabilizing gene expression programs. Although the Suv39h methyltransferases (KMTs) are known to ensure pericentric H3K9me3 methylation, the mechanisms that initiate and maintain mammalian heterochromatin organization remain elusive. We developed a biochemical assay and used in vivo analyses in mouse embryonic fibroblasts to identify Prdm3 and Prdm16 as redundant H3K9me1-specific KMTs that direct cytoplasmic H3K9me1 methylation. The H3K9me1 is converted in the nucleus to H3K9me3 by the Suv39h enzymes to reinforce heterochromatin. Simultaneous depletion of Prdm3 and Prdm16 abrogates H3K9me1 methylation, prevents Suv39h-dependent H3K9me3 trimethylation, and derepresses major satellite transcription. Most strikingly, DNA-FISH and electron microscopy reveal that combined impairment of Prdm3 and Prdm16 results in disintegration of heterochromatic foci and disruption of the nuclear lamina. Our data identify Prdm3 and Prdm16 as H3K9me1 methyltransferases and expose a functional framework in which anchoring to the nuclear periphery helps maintain the integrity of mammalian heterochromatin.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Heterocromatina , Histona-Lisina N-Metiltransferase/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Fibroblastos/metabolismo , Técnicas de Inativação de Genes , Células HeLa , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Humanos , Proteína do Locus do Complexo MDS1 e EVI1 , Camundongos , Lâmina Nuclear/metabolismo , Proto-Oncogenes , Fatores de Transcrição/genética
7.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35042812

RESUMO

Time efficiency of self-assembly is crucial for many biological processes. Moreover, with the advances of nanotechnology, time efficiency in artificial self-assembly becomes ever more important. While structural determinants and the final assembly yield are increasingly well understood, kinetic aspects concerning the time efficiency, however, remain much more elusive. In computer science, the concept of time complexity is used to characterize the efficiency of an algorithm and describes how the algorithm's runtime depends on the size of the input data. Here we characterize the time complexity of nonequilibrium self-assembly processes by exploring how the time required to realize a certain, substantial yield of a given target structure scales with its size. We identify distinct classes of assembly scenarios, i.e., "algorithms" to accomplish this task, and show that they exhibit drastically different degrees of complexity. Our analysis enables us to identify optimal control strategies for nonequilibrium self-assembly processes. Furthermore, we suggest an efficient irreversible scheme for the artificial self-assembly of nanostructures, which complements the state-of-the-art approach using reversible binding reactions and requires no fine-tuning of binding energies.


Assuntos
Nanoestruturas/química , Nanotecnologia/métodos , Polímeros/química , Algoritmos , Simulação por Computador , Cinética , Modelos Teóricos , Análise de Sistemas , Fatores de Tempo
8.
Eur Heart J ; 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39211948

RESUMO

BACKGROUND AND AIMS: In the FLOW trial, semaglutide reduced the risks of kidney and cardiovascular (CV) outcomes and death in participants with type 2 diabetes mellitus (T2D) and chronic kidney disease (CKD). These prespecified analyses assessed the effects of semaglutide on CV outcomes and death by CKD severity. METHODS: Participants were randomised to subcutaneous semaglutide 1 mg or placebo weekly. The main outcome was a composite of CV death, non-fatal myocardial infarction (MI) ornon-fatal stroke (CV death/MI/stroke) as well as death due to any cause by baseline CKD severity. CKD was categorised by eGFR < or ≥60 mL/min/1.73 m2, UACR < or ≥300 mg/g or KDIGO risk classification. RESULTS: 3533 participants were randomised with a median follow-up of 3.4 years. Low/moderate KDIGO risk was present in 242 (6.9%), while 878 (24.9%) had high and 2412 (68.3%) had very high KDIGO risk. Semaglutide reduced CV death/MI/stroke by 18% (HR 0.82 [95% CI 0.68-0.98]; P = .03), with consistency across eGFR categories, UACR levels and KDIGO risk classification (all P-interaction >.13). Death due to any cause was reduced by 20% (HR 0.80 [0.67-0.95]; P = .01), with consistency across eGFR categories and KDIGO risk class (P-interaction .21 and .23, respectively). The P-interaction treatment effect for death due to any cause by UACR was .01 (<300 mg/g HR 1.17 [0.83-1.65]; ≥300 mg/g HR 0.70 [0.57-0.85]). CONCLUSIONS: Semaglutide significantly reduced the risk of CV death/MI/stroke regardless of baseline CKD severity in participants with T2D.

9.
Clin Infect Dis ; 78(1): 154-163, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-37623745

RESUMO

INTRODUCTION: In high-burden settings, low-complexity screening tests for tuberculosis (TB) could expand the reach of community-based case-finding efforts. The potential costs and cost-effectiveness of approaches incorporating these tests are poorly understood. METHODS: We developed a microsimulation model assessing 3 approaches to community-based case-finding in hypothetical populations (India-, South Africa-, The Philippines-, Uganda-, and Vietnam-like settings) with TB prevalence 4 times that of national estimates: (1) screening with a point-of-care C-reactive protein (CRP) test, (2) screening with a more sensitive "Hypothetical Screening test" (95% sensitive for Xpert Ultra-positive TB, 70% specificity; equipment/labor costs similar to Xpert Ultra, but using a $2 cartridge) followed by sputum Xpert Ultra if positive, or (3) testing all individuals with sputum Xpert Ultra. Costs are expressed in 2023 US dollars and include treatment costs. RESULTS: Universal Xpert Ultra was estimated to cost a mean $4.0 million (95% uncertainty range: $3.5 to $4.6 million) and avert 3200 (2600 to 3900) TB-related disability-adjusted life years (DALYs) per 100 000 people screened ($670 [The Philippines] to $2000 [Vietnam] per DALY averted). CRP was projected to cost $550 (The Philippines) to $1500 (Vietnam) per DALY averted but with 44% fewer DALYs averted. The Hypothetical Screening test showed minimal benefit compared to universal Xpert Ultra, but if specificity were improved to 95% and per-test cost to $4.5 (all-inclusive), this strategy could cost $390 (The Philippines) to $940 (Vietnam) per DALY averted. CONCLUSIONS: Screening tests can meaningfully improve the cost-effectiveness of community-based case-finding for TB but only if they are sensitive, specific, and inexpensive.


Assuntos
Tuberculose , Humanos , Análise Custo-Benefício , Tuberculose/diagnóstico , Tuberculose/epidemiologia , África do Sul , Custos de Cuidados de Saúde , Escarro , Sensibilidade e Especificidade
10.
Kidney Int ; 106(1): 67-84, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38428734

RESUMO

Parietal epithelial cells (PECs) are kidney progenitor cells with similarities to a bone marrow stem cell niche. In focal segmental glomerulosclerosis (FSGS) PECs become activated and contribute to extracellular matrix deposition. Colony stimulating factor-1 (CSF-1), a hematopoietic growth factor, acts via its specific receptor, CSF-1R, and has been implicated in several glomerular diseases, although its role on PEC activation is unknown. Here, we found that CSF-1R was upregulated in PECs and podocytes in biopsies from patients with FSGS. Through in vitro studies, PECs were found to constitutively express CSF-1R. Incubation with CSF-1 induced CSF-1R upregulation and significant transcriptional regulation of genes involved in pathways associated with PEC activation. Specifically, CSF-1/CSF-1R activated the ERK1/2 signaling pathway and upregulated CD44 in PECs, while both ERK and CSF-1R inhibitors reduced CD44 expression. Functional studies showed that CSF-1 induced PEC proliferation and migration, while reducing the differentiation of PECs into podocytes. These results were validated in the Adriamycin-induced FSGS experimental mouse model. Importantly, treatment with either the CSF-1R-specific inhibitor GW2580 or Ki20227 provided a robust therapeutic effect. Thus, we provide evidence of the role of the CSF-1/CSF-1R pathway in PEC activation in FSGS, paving the way for future clinical studies investigating the therapeutic effect of CSF-1R inhibitors on patients with FSGS.


Assuntos
Glomerulosclerose Segmentar e Focal , Receptores de Hialuronatos , Fator Estimulador de Colônias de Macrófagos , Podócitos , Glomerulosclerose Segmentar e Focal/patologia , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/genética , Animais , Humanos , Podócitos/metabolismo , Podócitos/patologia , Fator Estimulador de Colônias de Macrófagos/metabolismo , Fator Estimulador de Colônias de Macrófagos/genética , Receptores de Hialuronatos/metabolismo , Receptores de Hialuronatos/genética , Camundongos , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Epiteliais/efeitos dos fármacos , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Glomérulos Renais/patologia , Glomérulos Renais/metabolismo , Masculino , Modelos Animais de Doenças , Células Cultivadas , Feminino , Regulação para Cima , Movimento Celular/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Transdução de Sinais , Camundongos Endogâmicos C57BL , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos
11.
Antimicrob Agents Chemother ; 68(7): e0023624, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38780262

RESUMO

CERTAIN-1 was a Phase 3, double-blind, randomized, parallel group study of the efficacy and safety of cefepime-taniborbactam versus meropenem in the treatment of adults with complicated urinary tract infection (cUTI), including acute pyelonephritis. We determined susceptibility of Enterobacterales and Pseudomonas aeruginosa baseline pathogens to cefepime-taniborbactam and comparators and characterized ß-lactam resistance mechanisms. Microbiologic response and clinical response were assessed in patient subsets defined by baseline pathogens that were of cefepime-, multidrug-, or carbapenem-resistant phenotype or that carried ß-lactamase genes. Among Enterobacterales baseline pathogens, 26.8%, 4.1%, and 3.0% carried genes for extended-spectrum ß-lactamases (ESBLs), AmpC, and carbapenemases, respectively. Within each treatment group, while composite success rates at Test of Cure in resistant subsets by pathogen species were similar to those by pathogen overall, composite success rates in meropenem patients were numerically lower for cefepime-resistant Escherichia coli (9/19; 47.4%) and ESBL E. coli (13/25; 52.0%) compared with E. coli overall (62/100; 62.0%). Cefepime-taniborbactam achieved composite success in 7/8 (87.5%) patients with carbapenem-resistant Enterobacterales and 8/9 (88.9%) patients with Enterobacterales with a carbapenemase gene (5 OXA-48-group; 2 KPC-3; 2 NDM-1). Cefepime-taniborbactam also achieved composite success in 8/16 (50.0%) patients and clinical success in 13/16 (81.3%) patients with P. aeruginosa; corresponding rates were 4/7 (57.1%) and 6/7 (85.7%) for meropenem. Cefepime-taniborbactam demonstrated efficacy in adult cUTI patients with cefepime-, multidrug-, and carbapenem-resistant pathogens including pathogens with ESBL, AmpC, and carbapenemase genes. CLINICAL TRIALS: This study is registered with ClinicalTrials.gov as NCT03840148.


Assuntos
Antibacterianos , Cefepima , Cefalosporinas , Meropeném , Testes de Sensibilidade Microbiana , Infecções Urinárias , beta-Lactamases , Humanos , Meropeném/uso terapêutico , Meropeném/farmacologia , Cefepima/uso terapêutico , Cefepima/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia , Cefalosporinas/uso terapêutico , Cefalosporinas/farmacologia , beta-Lactamases/genética , Adulto , Feminino , Masculino , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Pessoa de Meia-Idade , Método Duplo-Cego , Proteínas de Bactérias/genética , Genótipo , Fenótipo , Idoso , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Resultado do Tratamento , Ácidos Borínicos , Ácidos Carboxílicos
12.
Chemistry ; 30(36): e202401238, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38655832

RESUMO

The imidonitridosilicate Rb3Si6N5(NH)6, being only the second representative of this compound class, was synthesized ammonothermally at 870 K and 230 MPa. Its crystal structure was solved from single-crystal X-ray diffraction data. The imidonitridosilicate crystallizes isotypically with the respective potassium compound in space group P4132 with the lattice parameter a=10.9422(4) Šforming a three-dimensional imidonitridosilicate tetrahedra network with voids for the rubidium ions. The structure model and the presence of the imide groups were verified by Fourier-Transform infrared (FTIR) and magic-angle spinning (MAS) NMR spectroscopy, using cross polarization 15N{1H} and 29Si{1H} MAS NMR experiments. Rb3Si6N5(NH)6 represents a possible intermediate during the ammonothermal synthesis of nitridosilicates. The characterization of such intermediates improves the understanding of the reaction pathway from ammonothermal solutions to nitrides. Thus, the ammonothermal synthesis is an alternative approach to the well-established high-temperature synthesis leading to the compound class of nitridosilicates.

13.
Chemistry ; : e202402743, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39355989

RESUMO

The structural variability of a compound class is an important criterion for the research into phosphor host lattices for phosphor-converted light-emitting diodes (pc-LEDs). Especially, nitridophosphates and the related class of imidonitridophosphates are promising candidates. Recently, the ammonothermal approach has opened a systematic access to this substance class with larger sample quantities. We present the successful ammonothermal synthesis of the imidonitridophosphate Ba4P4N8(NH)2:Eu2+. Its crystal structure is solved by X-ray diffraction and it crystallizes in space group Cc (no. 9) with lattice parameters a = 12.5250(3), b = 12.5566(4), c = 7.3882(2) Å and ß = 102.9793(10)°. For the first time, adamantane-type (imido)nitridophosphate anions [P4N8(NH)2]8- are observed next to metal ions other than alkali metals in a compound. The presence of imide groups in the structure and the identification of preferred positions for the hydrogen atoms are performed using a combination of quantum chemical calculations, Fourier-transform infrared, and solid-state NMR spectroscopy. Eu2+ doped samples exhibit cyan emission (λmax = 498 nm, fwhm = 50 nm/1981 cm-1) when excited with ultraviolet light with an impressive internal quantum efficiency (IQE) of 41 %, which represents the first benchmark for imidonitridophosphates and is promising for potential industrial application of this compound class.

14.
FEMS Yeast Res ; 242024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38140959

RESUMO

Pulcherrimin is an iron (III) chelate of pulcherriminic acid that plays a role in antagonistic microbial interactions, iron metabolism, and stress responses. Some bacteria and yeasts produce pulcherriminic acid, but so far, pulcherrimin could not be produced in Saccharomyces cerevisiae. Here, multiple integrations of the Metschnikowia pulcherrima PUL1 and PUL2 genes in the S. cerevisiae genome resulted in red colonies, which indicated pulcherrimin formation. The coloration correlated positively and significantly with the number of PUL1 and PUL2 genes. The presence of pulcherriminic acid was confirmed by mass spectrometry. In vitro competition assays with the plant pathogenic fungus Botrytis caroliana revealed inhibitory activity on conidiation by an engineered, strong pulcherrimin-producing S. cerevisiae strain. We demonstrate that the PUL1 and PUL2 genes from M. pulcherrima, in multiple copies, are sufficient to transfer pulcherrimin production to S. cerevisiae and represent the starting point for engineering and optimizing this biosynthetic pathway in the future.


Assuntos
Metschnikowia , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Botrytis/genética , Botrytis/metabolismo , Metschnikowia/genética , Metschnikowia/metabolismo , Ferro/metabolismo
15.
Eur J Haematol ; 113(5): 704-715, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39101601

RESUMO

OBJECTIVES: There is limited data on the incidence, prevalence, and treatments for myelofibrosis (MF) in Germany. This retrospective study examined claims data from 3.3 million insured individuals, spanning from 2010 to 2021. METHODS: Four sensitivity scenarios were explored to identify cases of MF. Point prevalence and cumulative incidence of MF were determined as of December 31, 2021, and within 2021, respectively. A cross-sectional analysis used the main scenario definition of MF to identify cases and evaluate the period prevalence of patients receiving treatment for symptoms and/or splenomegaly, including first-line (1L) Janus kinase inhibitor (JAKi), second-line, or further (2L+) MF-related treatment therapies during 2021. The prevalence of anemia treatment was also reported. RESULTS: The estimated standardized point prevalence of MF on December 31, 2021, was 9.9-12.4 cases per 100 000 persons, and cumulative incidence in 2021 was 1.2-1.8 cases per 100 000 persons. Standardized period prevalence in 2021 for MF patients receiving 1L JAKi and/or 2L+ MF-related treatment was 4.0 cases per 100 000. Among these patients, 47.1%-53.7% required treatment for anemia, resulting in a period prevalence of 1.9-2.2 cases per 100 000 individuals. CONCLUSION: The data reveal gaps in MF treatments and the need to improve patient quality of life.


Assuntos
Anemia , Mielofibrose Primária , Humanos , Mielofibrose Primária/epidemiologia , Mielofibrose Primária/tratamento farmacológico , Mielofibrose Primária/diagnóstico , Alemanha/epidemiologia , Anemia/epidemiologia , Anemia/etiologia , Anemia/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Incidência , Prevalência , Adulto , Idoso de 80 Anos ou mais , Gerenciamento Clínico , Estudos Retrospectivos , Estudos Transversais , Revisão da Utilização de Seguros , Análise de Dados , Adulto Jovem , Adolescente
16.
Chemotherapy ; 69(1): 27-34, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37336201

RESUMO

Trifluridine/tipiracil is approved for the use in later or last-line setting in previously treated metastatic colorectal cancer (mCRC) patients who progressed on standard anti-tumor drugs including 5-fluorouracil (5-FU), irinotecan, oxaliplatin, anti-VEGF and anti-EGFR antibodies, or who are not considered candidates for those standard therapies. In this report, we describe a 67-year-old male patient with KRAS-mutated mCRC and metachronous liver and lung metastasis who failed prior 5-FU- and irinotecan-containing regimens, but then showed long-term disease control for 31 months on single-agent trifluridine/tipiracil given as second-line treatment. According to our experience, trifluridine/tipiracil is a feasible and effective treatment option in earlier but not necessarily last-line therapy in mCRC patients who are not considered candidates for doublet or triplet chemotherapy. Besides its efficacy, it is associated with maintained quality of life and a manageable toxicity profile. Considering increasing age of mCRC patients and their wish for maintaining an independent lifestyle, further research on the use of trifluridine/tipiracil in earlier lines of systemic mCRC therapy is warranted.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Pirrolidinas , Timina , Masculino , Humanos , Idoso , Intervalo Livre de Progressão , Uracila/uso terapêutico , Neoplasias Colorretais/patologia , Trifluridina/uso terapêutico , Trifluridina/efeitos adversos , Irinotecano/uso terapêutico , Qualidade de Vida , Neoplasias do Colo/tratamento farmacológico , Fluoruracila/uso terapêutico , Combinação de Medicamentos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
17.
BMC Ophthalmol ; 24(1): 391, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227854

RESUMO

BACKGROUND: Regional anaesthesia education, especially for ocular procedures, necessitates reliable surgical training models. While cadaveric models offer anatomical fidelity, conventional embalming methods may compromise tissue integrity. We aimed to assess the effectiveness of Thiel cadavers for training in sub-Tenon's blocks by evaluating ocular tissues and measuring insertion forces. METHODS: Experimental design, using twenty eyes from ten Thiel cadaver heads. These cadavers were specifically prepared to test the administration of sub-Tenon's blocks. The research was conducted in a controlled laboratory setting appropriate for handling cadaveric materials and conducting precise measurements. Each cadaver eye underwent an initial ultrasound examination, and its axial length was noted. An intravitreal injection of heptastarch solution followed, to re-establish the eye's sphericity. After this volume injection, the axial length and intraocular pressure were measured again. Mock sub-Tenon's blocks were administered in 2 separate quadrants of the eye, with insertion forces measured using a pressure gauge. These were compared to a data set of insertion forces measured in a series of isolated pig's eyes on which STBs had been performed. Main outcome measurements were macroscopic assessment of the ocular tissue layers and the insertion forces required for the sub-Tenon's blocks. In a second set of 10 Thiel cadaver heads, 5 ml of sodium chloride were injected as sub-Tenon's blocks and the emergence of a periocular "T-sign" ascertained and measured by ultrasound. RESULTS: Four of twenty eyes (20%) retained near-natural sphericity, with the remaining requiring volume injection to approximate physiological shape and pressure. The conjunctiva and Tenon's layer were intact, and correct cannula placement was achieved in all cases. In 16 of 20 eyes where T-signs could be measured, the median thickness of the T-sign amounted to 2.72 mm (range 1.34 mm-5.28 mm). The average maximum cannula insertion force was 2.92 Newtons. Insertion forces in intact Thiel cadaver heads were consistently higher than in isolated pig's eyes (3.6 N vs 2.0 N). CONCLUSION: These findings suggest that Thiel cadavers are a promising model for training in sub-Tenon'sblocks, despite the challenge of often desiccated and involuted eyes.


Assuntos
Cadáver , Estudos de Viabilidade , Humanos , Animais , Suínos , Cápsula de Tenon , Bloqueio Nervoso/métodos , Oftalmologia/educação , Pressão Intraocular/fisiologia
18.
World J Surg Oncol ; 22(1): 246, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267062

RESUMO

BACKGROUND: Intraosseous myofibroma of the jaw is a rare neoplasm of mesenchymal origin with limited comprehensive understanding. It typically affects patients in the first two decades of life with a male predilection. CASE PRESENTATION: This study presents a rare case of myofibroma mimicking an odontogenic lesion in a 2-year-old boy. The patient presented with an incidental finding of a painless swelling of the right mandibular ramus of unknown etiology. Imaging analysis revealed a solid, expansile lesion adjacent to the germinal zone of the right mandibular first molar. Histopathologic analysis and immunohistochemistry after incisional biopsy suggested a possible central odontogenic fibroma, and the patient underwent total enucleation, leading to the final diagnosis of intraosseous myofibroma. Follow-up examinations showed no evidence of recurrence. CONCLUSIONS: This report contributes to the understanding of myofibroma in pediatric patients and underscores the critical role of meticulous histopathologic examination for effective surgical planning and optimal patient outcomes.


Assuntos
Neoplasias Mandibulares , Miofibroma , Tumores Odontogênicos , Humanos , Masculino , Miofibroma/diagnóstico , Miofibroma/cirurgia , Miofibroma/patologia , Miofibroma/diagnóstico por imagem , Diagnóstico Diferencial , Pré-Escolar , Tumores Odontogênicos/diagnóstico , Tumores Odontogênicos/cirurgia , Tumores Odontogênicos/patologia , Tumores Odontogênicos/diagnóstico por imagem , Neoplasias Mandibulares/cirurgia , Neoplasias Mandibulares/patologia , Neoplasias Mandibulares/diagnóstico , Neoplasias Mandibulares/diagnóstico por imagem , Prognóstico
19.
Urol Int ; 108(3): 175-182, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38316122

RESUMO

INTRODUCTION: Symptomatic lymphocele remains a relevant complication after pelvic tumor surgery. This study aims to investigate how the number of lymph nodes removed may influence postoperative outcomes and if it increases the probability of detecting lymph node metastasis. METHODS: The study included 500 patients who underwent RARP including lymphadenectomy performed by a single surgeon. Patients were divided into two groups: group 1 consisted of 308 patients with 20 or fewer lymph nodes removed (mean 15), while group 2 had 192 patients with over 20 nodes removed (mean 27). Perioperative data were analyzed, and postoperative outcomes were compared between groups. RESULTS: Overall, lymph node metastasis was detected in 17.8% of men. In detail, out of 19.6 lymph nodes removed, an average of 3.14 lymph nodes per patient showed metastasis, with a slightly higher incidence of 19.7% in group 2 compared to 16.5% in group 1, though not statistically significant (p = 0.175). The number of lymph node metastases was significantly higher in group 2 patients (3.47) versus group 1 (2.37) (p = 0.048). All complications except symptomatic lymphoceles (p = 0.004) were not significantly different between groups. Univariate linear regression analysis revealed no correlation between the number of removed lymph nodes and symptomatic lymphocele. However, it did correlate with catheter days and readmissions. CONCLUSION: A correlation may exist between the number of lymph nodes removed during RARP and an increased incidence of complications, particularly symptomatic lymphocele. A more extensive PLND may result in prolonged catheter days and increased readmissions. With the increased extent of pelvic lymphadenectomy, the probability of detecting lymphogenic metastasis rises. The diagnostic value of PLND is well established. Further randomized trials are needed to weigh its necessity and extent.


Assuntos
Excisão de Linfonodo , Metástase Linfática , Linfocele , Humanos , Masculino , Excisão de Linfonodo/efeitos adversos , Pessoa de Meia-Idade , Linfocele/etiologia , Linfocele/epidemiologia , Idoso , Resultado do Tratamento , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Linfonodos/patologia , Linfonodos/cirurgia , Prostatectomia/métodos , Prostatectomia/efeitos adversos , Estudos Retrospectivos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Adulto , Feminino
20.
Skeletal Radiol ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042200

RESUMO

PURPOSE: To elaborate an optimized scheme for the Dejour classification of trochlear dysplasia based on axial and sagittal MR images and to evaluate its intra- and inter-reader reliability. MATERIAL AND METHODS: Over a period of 20 months patients with a knee MRI and the diagnosis of trochlear dysplasia were retrospectively included. Exclusion criteria were incomplete examination, qualitatively non-diagnostic examination, post trochlear surgery, missing informed consent for research purposes. Three independent evaluations were performed by two radiologists: first using an established description of the Dejour classification (types A-D) and then two evaluations using a new adapted scheme (types A-D). The adapted scheme includes a shallow trochlea, in type A no spur/no cliff, in type B with spur/no cliff, in type C no spur/with cliff, and in type D with spur/with cliff. RESULTS: One hundred seventy-one knee MRIs (female:65.5%; left side:52.6%) were included with a median age of 34.3 years (range:11.3-79.2). Inter-reader reliability using the established description was fair for the four-type-classification (kappa(k) = 0.23; 95%CI:0.11-0.34), fair for differentiation low-grade versus high-grade dysplasia (k = 0.28;0.13-0.43), slight for differentiation spur versus no-spur types (k = 0.20;0.05-0.34). Inter-reader reliability using the adapted scheme was substantial (k = 0.79;0.75-0.83) for the four-type-classification, substantial for differentiation low-grade versus high-grade dysplasia (k = 0.80;0.75-0.85), substantial for differentiation spur versus no-spur presence (k = 0.76;0.71-0.81). Intra-reader reliability was almost perfect for the adapted scheme (k-values: 0.88-0.95; 95%CIs: 0.84-0.98). CONCLUSION: The novel adapted scheme for Dejour classification shows an almost perfect intra-reader reliability and a substantially higher inter-reader reliability. It may become a helpful tool in the daily diagnostic work of radiologists.

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