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1.
J Am Chem Soc ; 146(12): 7905-7914, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38478891

RESUMO

Experimental and computational studies illuminating the factors that guide metal-centered stereogenicity and, therefrom, selectivity in transfer hydrogenative carbonyl additions of alcohol proelectrophiles catalyzed by chiral-at-metal-and-ligand octahedral d6 metal ions, iridium(III) and ruthenium(II), are described. To augment or invert regio-, diastereo-, and enantioselectivity, predominantly one from among as many as 15 diastereomeric-at-metal complexes is required. For iridium(III) catalysts, cyclometalation assists in defining the metal stereocenter, and for ruthenium(II) catalysts, iodide counterions play a key role. Whereas classical strategies to promote selectivity in metal catalysis aim for high-symmetry transition states, well-defined low-symmetry transition states can unlock selectivities that are otherwise difficult to achieve or inaccessible.

2.
Nature ; 562(7728): 569-573, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30356182

RESUMO

The cause of changes in atmospheric carbon dioxide (CO2) during the recent ice ages is yet to be fully explained. Most mechanisms for glacial-interglacial CO2 change have centred on carbon exchange with the deep ocean, owing to its large size and relatively rapid exchange with the atmosphere1. The Southern Ocean is thought to have a key role in this exchange, as much of the deep ocean is ventilated to the atmosphere in this region2. However, it is difficult to reconstruct changes in deep Southern Ocean carbon storage, so few direct tests of this hypothesis have been carried out. Here we present deep-sea coral boron isotope data that track the pH-and thus the CO2 chemistry-of the deep Southern Ocean over the past forty thousand years. At sites closest to the Antarctic continental margin, and most influenced by the deep southern waters that form the ocean's lower overturning cell, we find a close relationship between ocean pH and atmospheric CO2: during intervals of low CO2, ocean pH is low, reflecting enhanced ocean carbon storage; and during intervals of rising CO2, ocean pH rises, reflecting loss of carbon from the ocean to the atmosphere. Correspondingly, at shallower sites we find rapid (millennial- to centennial-scale) decreases in pH during abrupt increases in CO2, reflecting the rapid transfer of carbon from the deep ocean to the upper ocean and atmosphere. Our findings confirm the importance of the deep Southern Ocean in ice-age CO2 change, and show that deep-ocean CO2 release can occur as a dynamic feedback to rapid climate change on centennial timescales.


Assuntos
Atmosfera/química , Dióxido de Carbono/análise , Sequestro de Carbono , Água do Mar/química , Animais , Regiões Antárticas , Antozoários/química , Boro , Dióxido de Carbono/metabolismo , Clima , Groenlândia , História Antiga , Concentração de Íons de Hidrogênio , Gelo/análise , Isótopos , Modelos Teóricos , Oceanos e Mares , Fatores de Tempo
3.
BMC Public Health ; 24(1): 222, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238734

RESUMO

BACKGROUND: Many people suffer from body and breath malodour syndromes. One of these is trimethylaminuria, a condition characterized by excretion in breath and bodily fluids of trimethylamine, a volatile and odorous chemical that has the smell of rotting fish. Trimethylaminuria can be primary, due to mutations in the gene encoding flavin-containing monooxygenase 3, or secondary, due to various causes. To gain a better understanding of problems faced by United Kingdom residents affected by body and breath malodour conditions, we conducted a survey. METHODS: Two anonymous online surveys, one for adults and one for parents/guardians of affected children, were conducted using the Opinio platform. Participants were invited via a trimethylaminuria advisory website. Questions were a mix of dropdown, checkbox and open-ended responses. Forty-four adults and three parents/guardians participated. The dropdown and checkbox responses were analysed using the Opinio platform. RESULTS: All participants reported symptoms of body/breath odour. However, not all answered every question. Twenty-three respondents experienced difficulties in being offered a diagnostic test for trimethylaminuria. Problems encountered included lack of awareness of the disorder by medical professionals and reluctance to recognise symptoms. Of those tested, 52% were diagnosed with trimethylaminuria. The main problems associated with living with body/breath malodours were bullying, harassment and ostracism in either the workplace (90%) or in social settings (88%). All respondents thought their condition had disadvantaged them in their daily lives. Open-ended responses included loss of confidence, stress, exclusion, isolation, loneliness, depression and suicidal thoughts. Respondents thought their lives could be improved by greater awareness and understanding of malodour conditions by medical professionals, employers and the general public, and appreciation that the malodour was due to a medical condition and not their fault. CONCLUSIONS: Breath and body malodour conditions can cause immense hardship and distress, both mentally and socially, having devastating effects on quality of life. It would be advantageous to establish a standardised pathway from primary care to a specialist unit with access to a robust and reliable test and diagnostic criteria. There is a need to recognise malodour disorders as a disability, giving affected individuals the same rights as those with currently recognised disabilities.


Assuntos
Erros Inatos do Metabolismo , Metilaminas/urina , Qualidade de Vida , Adulto , Criança , Animais , Humanos , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo/genética , Odorantes , Ansiedade
4.
Syst Parasitol ; 101(3): 36, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700605

RESUMO

The adults of Haemaphysalis (Rhipistoma) adleri Feldman-Muhsam, 1951 (Acari: Ixodidae) are redescribed and the larva of this species is described for the first time here. The adults of H. adleri that we studied were collected from various canid, felid and hyaenid carnivorans (Carnivora: Canidae, Felidae, Hyaenidae) as well as a hedgehog (Erinaceomorpha: Erinaceidae) in Iraq, Israel and West Bank. The males, females and larvae of H. adleri can be differentiated from Haemaphysalis (Rhipistoma) species occurring in the Palearctic portion of West Asia and Egypt as well those in the H. asiatica subgroup by the length of idiosomal setae, development and size of spurs on palpi, dental formula on the hypostome and size of spur on coxae. A lectotype of H. adleri has been designated and the geographic distribution and hosts of this tick species are discussed.


Assuntos
Ixodidae , Larva , Especificidade da Espécie , Animais , Larva/anatomia & histologia , Ixodidae/classificação , Ixodidae/anatomia & histologia , Ixodidae/parasitologia , Feminino , Masculino , Carnívoros/parasitologia , Ásia Ocidental
5.
J Am Chem Soc ; 145(14): 8242-8247, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36996284

RESUMO

The first systematic study of catalytic enantioselective 1,2-additions to acrolein is described. Specifically, using allyl alcohol as a tractable, inexpensive acrolein proelectrophile, iridium-catalyzed acrolein allylation is achieved with high levels of regio-, anti-diastereo-, and enantioselectivity. This process delivers 3-hydroxy-1,5-hexadienes, a useful compound class that is otherwise challenging to access via enantioselective catalysis. Two-fold use of this method unlocks concise total syntheses of amphidinolide R (9 vs 23 steps, LLS) and amphidinolide J (9 vs 23 or 26 steps, LLS), which are prepared in fewer than half the steps previously possible, and the first total synthesis of amphidinolide S (10 steps, LLS).


Assuntos
Álcoois , Compostos Alílicos , Acroleína , Estereoisomerismo
6.
J Vasc Surg ; 77(3): 778-784, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37221895

RESUMO

OBJECTIVE: The Society for Vascular Surgery published abdominal aortic aneurysm (AAA) practice guidelines in 2003, 2009, and 2018 to improve the management and treatment of AAAs. In 2014, our vascular surgery department implemented a quarterly AAA dashboard (AAAdb) to record the perioperative outcomes and guideline compliance with a focus on intervention appropriateness and procedural follow-up, which supplemented our Vascular Quality Initiative data. From the available reported evidence and expert consensus opinions, nine additional criteria for the appropriate treatment of AAAs <5 cm in women and <5.5 cm in men were noted, when applicable. The purpose of our study was to assess the effects of AAAdb implementation on adherence to society and institutional guidelines, documentation of treatment rationale, and the quality of follow-up. METHODS: We performed a retrospective review of elective open and endovascular AAA repair at a single institution from 2010 to 2018. The AAAdb was implemented in the middle of this period in 2014. The patient demographics, aortic size, repair indication, repair type, 30-day mortality, and postoperative and 1-year follow-up imaging findings were analyzed. The primary outcome was adherence to intervention appropriateness and the follow-up guidelines. The categorical factors were summarized using frequencies and percentages and compared using the Pearson χ2 test or Fisher exact test. Continuous measures were summarized using the mean ± standard deviation and compared between study periods using two-sample t tests. RESULTS: From 2010 to 2018, 1549 patients had undergone elective AAA repair: 657 before and 892 after AAAdb implementation. No differences were found in AAA size after AAAdb (5.6 ± 1.2 cm vs 5.6 ± 1.1 cm; P = .88). However, the proportion of size-appropriate repairs increased (64.1% vs 71.3%; P = .003). The proportion of small AAA repairs with a documented rationale had increased (64.4% vs 80.5%; P < .001), with rapid disease progression cited most often. No difference was found in 30-day mortality (1.2% vs 1.5%; P = .69). Follow-up imaging after endovascular abdominal aortic aneurysm repair increased at <60 days postoperatively (76% vs 84%; P = .004) and at 1 year of follow-up (78% vs 86%; P = .0005). The proportion of patients with endoleak at <60 days postoperatively had increased in the post-AAAdb cohort (21% vs 29%; P = .012). CONCLUSIONS: The AAAdb served as a centerpiece for improving the appropriateness of care and compliance with national and institutional guidelines, including treatment of small AAAs in special circumstances. Its implementation was associated with higher quality follow-up and surveillance in a high-volume, regional aortic center. Consideration should be given to adding additional criteria to the Society for Vascular Surgery guidelines and Vascular Quality Initiative reporting.


Assuntos
Aneurisma da Aorta Abdominal , Masculino , Humanos , Feminino , Aorta , Consenso , Confiabilidade dos Dados
7.
J Org Chem ; 88(8): 4965-4974, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-36449710

RESUMO

In this Perspective, the use of methanol and ethanol as C1 and C2 feedstocks in metal-catalyzed C-C couplings to π-unsaturated pronucleophiles via hydrogen auto-transfer is surveyed. In these processes, alcohol oxidation to form an aldehyde electrophile is balanced by reduction of an π-unsaturated hydrocarbon to form a transient organometallic nucleophile. Mechanistically related reductive couplings of paraformaldehyde mediated by alcohol reductants or formic acid also are described. These processes encompass the first catalytic enantioselective C-C couplings of methanol and ethanol and, more broadly, illustrate how the native reducing ability of alcohols enable the departure from premetalated reagents in carbonyl addition.

8.
Ann Vasc Surg ; 96: 166-175, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37169247

RESUMO

BACKGROUND: Cardiovascular complications are a major cause of morbidity and mortality in the postoperative period after major vascular surgery. Depending on the study population, up to 25% of patients have troponin elevation after noncardiac surgery, yet many do not meet the diagnosis of myocardial infarction (MI). Although outcomes of routine troponin elevation in patients undergoing mixed major vascular surgery have been evaluated, this has not been studied exclusively in elective, open abdominal aortic aneurysm repair (oAAA), especially regarding perioperative and overall mortality. METHODS: We conducted a single-center, retrospective review of routine troponin surveillance for consecutive, oAAA from 2014 to 2019. A total of 319 patients were identified and analyzed for management patterns and interventions. The cohort was stratified into groups for comparison based on those in whom troponin was routinely checked (RC) as part of a care strategy during the study period, not routinely checked (NRC), elevated troponin (ET) >0.001 ng/mL, and not elevated. The median follow-up was 21.5 ± 23.8 months. Groups were compared on demographic data, cardiac comorbidities, 30-day and 3-year outcomes for MI and death using two-sample t-tests, Wilcoxon rank sum tests, Pearson chi-square tests, and Fisher exact tests when appropriate. RESULTS: Troponin was measured in 83.7% (267/319) of patients who underwent elective oAAA repair. Routine troponin checks were obtained in 79.9% (255/319) of patients. ET was identified in 16.5% of those with RC (42/255) and 4.7% of those with NRC (3/64). Of patients with ET, 37.8% (17/45) had a cardiology consultation, 4.4% (2/45) had a percutaneous coronary intervention (PCI), and 4.4% (2/45) had another cardiac intervention. All 4 patients undergoing PCI or other cardiac intervention had received routine troponin checks. Patients with ET were older (71.2 vs. 68.6; P = 0.04), more likely to receive intraoperative blood products (P = 0.003), had longer operative times (P = 0.011), higher length of stay (9 vs. 7 days; P < 0.01), and higher 30-day MI rate (3 vs. 0; P = 0.04). They had neither longer aortic clamp times nor worse preoperative cardiac function, and the proximal clamp position during oAAA repair did not impact troponin detection. Additionally, 3-year overall mortality was increased in patients who had ET but there was not a significant difference in 3-year mortality between groups receiving routine troponin checks versus not. CONCLUSIONS: ET, identified after elective oAAA repair, was associated with a higher risk of 30-day MI and lower overall survival. However, it was not demonstrated that routine assessment of troponin levels postoperatively leads to decreased 3-year mortality in this setting.


Assuntos
Aneurisma da Aorta Abdominal , Infarto do Miocárdio , Intervenção Coronária Percutânea , Procedimentos de Cirurgia Plástica , Humanos , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia
9.
J Strength Cond Res ; 37(12): 2381-2388, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37535935

RESUMO

ABSTRACT: Hammert, WB, Moreno, EN, Martin, CC, Jessee, MB, and Buckner, SL. Skeletal muscle adaptations to high-load resistance training with pre-exercise blood flow restriction. J Strength Cond Res 37(12): 2381-2388, 2023-This study aimed to determine if blood flow restriction (BFR) could augment adaptations to a high-load training protocol that was inadequate for muscle growth. Forty nontrained individuals had each arm assigned to 1 of 3 elbow flexion protocols: (a) high-load resistance training [TRAD; 4 sets to muscular failure at 70% 1 repetition maximum (1RM)], (b) low repetition high-load resistance training with pre-exercise BFR (PreBFR; 4 sets of 3 repetitions at 70% 1RM + 3 min of pre-exercise BFR), and (c) low repetition high-load resistance training (LRTRAD); 4 sets of 3 repetitions at 70% 1RM). Muscle thickness (MT), 1RM strength, and local muscular endurance (LME) of the elbow flexors were measured before and after 8 weeks. An alpha level of 0.05 was used for all comparisons. For the 50% site, MT increased for TRAD (0.211 cm, 95% confidence interval [95% CI]: 0.143-0.280), PreBFR (0.105 cm, 95% CI: 0.034-0.175), and LRTRAD (0.073 cm, 95% CI: 0.000-0.146). The change for TRAD was greater than PreBFR and LRTRAD. For the 60% site, MT increased for TRAD (0.235 cm, 95% CI: 0.153-0.317), PreBFR (0.097 cm, 95% CI: 0.014-0.180), and LRTRAD (0.082 cm, 95% CI: 0.000-0.164). The change for TRAD was greater than PreBFR and LRTRAD. For the 70% site MT increased for TRAD (0.308 cm, 95% CI: 0.247-0.369), PreBFR (0.103 cm, 95% CI: 0.041-0.166), and LRTRAD (0.070 cm, 95% CI: 0.004-0.137). The change for TRAD was greater than PreBFR and LRTRAD. One repetition maximum and LME significantly increased for each condition, with no differences between conditions. Collapsed across conditions 1RM strength increased 2.094 kg (95% CI: 1.771-2.416) and LME increased 7.0 repetitions (95% CI: 5.7-8.3). In conclusion, the application of BFR to low-repetition, high-load training did not enhance the adaptative response.


Assuntos
Músculo Esquelético , Treinamento Resistido , Humanos , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Força Muscular/fisiologia , Hemodinâmica , Cotovelo , Fluxo Sanguíneo Regional/fisiologia
10.
J Am Chem Soc ; 144(19): 8487-8492, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35510915

RESUMO

Helical polymers with a defined main-chain atropoisomeric conformation are important materials in high value applications such as nonlinear optics and chiral separations. Currently, no methods exist for the cationic helix-sense-selective polymerization of prochiral vinyl monomers, which limits access to a number of potentially valuable optically active helical polymers. Here, we demonstrate the first stereoselective cationic helix-sense-selective polymerization of a prochiral vinyl monomer, which provides access to optically active helices of poly(N-vinylcarbazole). Chiral bis(oxazoline)-scandium Lewis acids serve as chiral counterions to polymerize N-vinylcarbazole into highly isotactic (up to 94% meso triads) polymers. Mechanistic investigations uncovered the distinct phenomenon that are responsible for independent control of conformational (i.e., helicity) and configurational (i.e., tacticity) stereochemistry. Polymer helicity was strongly influenced by the stereoselectivity of the first monomer propagation, whereas polymer tacticity was dictated by the thermodynamically controlled conformation of the growing polymer chain end. Overall, this method expands the suite of accessible helical polymers through helix-sense-selective polymerization and provides mechanistic insight into how polymer tacticity and helicity can be controlled independently.


Assuntos
Ácidos de Lewis , Polímeros , Catálise , Cátions , Polimerização , Polímeros/química , Estereoisomerismo
11.
J Vasc Surg ; 76(3): 733-740.e2, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35278651

RESUMO

OBJECTIVE: The Gore Excluder iliac branch endoprosthesis (IBE; W.L. Gore & Associates, Flagstaff, AZ) is the only iliac branch device approved in the United States to preserve blood flow to the external and internal iliac arteries (IIAs). Some surgeons have used the Gore Viabahn VBX balloon expandable endoprosthesis (VBX; W.L. Gore & Associates) in the IIA rather than the self-expanding endograft designed for the IBE, the internal iliac component (IIC). The objective of the present study was to examine the outcomes for patients treated for aortoiliac artery aneurysms using the IBE with either the IIC or VBX stent. METHODS: We performed a retrospective, single-center review of patients treated for aortoiliac artery aneurysms using the Gore IBE device, with either the IIC or VBX stent into the IIA, from February 2016 to March 2021. The patient demographics, procedure details, 30-day morbidity and mortality, and 6-month and 1-year outcomes and mortality were analyzed. The categorical factors are summarized using frequencies and proportions. Continuous measures are summarized as the mean ± standard deviation. A significance level of P = .05 was assumed for all test results. The analyses were performed using SAS software, version 9.4 (SAS Institute, Cary, NC). RESULTS: A total of 62 patients (64 arteries) had undergone elective aortoiliac artery aneurysm repair with the IBE. The IIC was used exclusively in 35 cases (55%) and the VBX in 29 (45%). The patients who had received the VBX had had a higher American Society of Anesthesiologists class (P = .006). Upper extremity access was used for VBX delivery in 24.1% of the procedures. No return to the operating room was required in either group. No differences were found in technical success (IIC, 97.1%; VBX, 93.1%; P = .59), the presence of endoleak on completion (20.0% vs 6.9%; P = .17), readmission (97.1% vs 93.1%; P = .59), or mortality (1.6% vs 0%; P = .45) at 30 days. No differences were found in the requirement for any IBE reintervention after 30 days. No type Ia, Ib, or III endoleaks had occurred in either group at any follow-up point. No significant difference was found in internal iliac limb primary patency (IIC, 100%; VBX, 96.3%) between groups. A nonstatistically significant trend was found toward fewer trunk-ipsilateral leg type II endoleaks in the VBX group during follow-up. CONCLUSIONS: These data suggest that the VBX is a reasonable substitute for the IIC, with a comparable safety and efficacy profile. Given its inherent conformability, greater range of diameters, and longer working length, the VBX stent offers expanded IIA branch options with the IBE.


Assuntos
Implante de Prótese Vascular , Procedimentos Endovasculares , Aneurisma Ilíaco , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Endoleak/etiologia , Procedimentos Endovasculares/efeitos adversos , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Aneurisma Ilíaco/etiologia , Aneurisma Ilíaco/cirurgia , Desenho de Prótese , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
12.
Value Health ; 25(12): 1929-1938, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35525833

RESUMO

OBJECTIVES: Striking disparities in access to radiation therapy (RT) exist, especially among racial and ethnic-minority patients. We analyzed census block group data to evaluate differences in travel distance to RT as a function of race and ethnicity, socioeconomic status, and rurality. METHODS: The Directory of Radiotherapy Centers provided the addresses of facilities containing linear accelerators for RT. We classified block groups as majority (≥ 50%) American Indian/Alaska Native (AI/AN), black, white, Asian, no single racial majority, or Hispanic regardless of race. We used the Area Deprivation Index to classify deprivation and Rural-Urban Commuting Area codes to classify rurality. Generalized linear mixed models tested associations between these factors and distance to nearest RT facility. RESULTS: Median distance to nearest RT facility was 72 miles in AI/AN-majority block groups, but 4 to 7 miles in block groups with non-AI/AN majorities. Multivariable models estimated that travel distances in AI/AN-majority block groups were 39 to 41 miles longer than in areas with non-AI/AN majorities. Travel distance was 1.3 miles longer in the more deprived areas versus less deprived areas and 16 to 32 miles longer in micropolitan, small town, and rural areas versus metropolitan areas. CONCLUSIONS: Cancer patients in block groups with AI/AN-majority populations, nonmetropolitan location, and low socioeconomic status experience substantial travel disparities in access to RT. Future research with more granular community- and individual-level data should explore the many other known barriers to access to cancer care and their relationship to the barriers posed by distance to RT care.


Assuntos
Etnicidade , Humanos , Estados Unidos , Disparidades em Assistência à Saúde , Acessibilidade aos Serviços de Saúde , População Rural
13.
Chem Rev ; 120(8): 3721-3748, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32191438

RESUMO

Catalytic reductive coupling of enone, acrylate, or vinyl heteroaromatic pronucleophiles with carbonyl or imine partners offers an alternative to base-mediated enolization in aldol- and Mannich-type reactions. In this review, direct catalytic reductive aldol and Mannich reactions are exhaustively catalogued on the basis of metal or organocatalyst. Stepwise processes involving enone conjugate reduction to form discrete enol or (metallo)enolate derivatives followed by introduction of carbonyl or imine electrophiles and aldol reactions initiated via enone conjugate addition are not covered.


Assuntos
Acrilatos/química , Alcenos/química , Cetonas/química , Compostos de Vinila/química , Catálise , Complexos de Coordenação/química , Iminas/química , Metais Pesados/química , Oxirredução
14.
Angew Chem Int Ed Engl ; 61(14): e202115959, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35119714

RESUMO

Cyclometallated iridium-PhanePhos complexes generated in situ from [Ir(cod)Cl]2 and (R)-PhanePhos catalyze 2-propanol-mediated reductive couplings of 2-substituted dienes with oxetanone and N-acyl-azetidinones to form branched homoallylic oxetanols and azetidinols with excellent control of regio- and enantioselectivity without C-C cleavage of the strained ring via enantiotopic π-facial selection of transient allyliridium nucleophiles. This work represents the first systematic study of enantioselective additions to symmetric ketones.


Assuntos
Compostos Alílicos , Irídio , 2-Propanol , Catálise , Polienos , Estereoisomerismo
15.
Clin Infect Dis ; 72(8): 1369-1378, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-32150603

RESUMO

BACKGROUND: The optimal dosing of antibiotics in critically ill patients receiving renal replacement therapy (RRT) remains unclear. In this study, we describe the variability in RRT techniques and antibiotic dosing in critically ill patients receiving RRT and relate observed trough antibiotic concentrations to optimal targets. METHODS: We performed a prospective, observational, multinational, pharmacokinetic study in 29 intensive care units from 14 countries. We collected demographic, clinical, and RRT data. We measured trough antibiotic concentrations of meropenem, piperacillin-tazobactam, and vancomycin and related them to high- and low-target trough concentrations. RESULTS: We studied 381 patients and obtained 508 trough antibiotic concentrations. There was wide variability (4-8-fold) in antibiotic dosing regimens, RRT prescription, and estimated endogenous renal function. The overall median estimated total renal clearance (eTRCL) was 50 mL/minute (interquartile range [IQR], 35-65) and higher eTRCL was associated with lower trough concentrations for all antibiotics (P < .05). The median (IQR) trough concentration for meropenem was 12.1 mg/L (7.9-18.8), piperacillin was 78.6 mg/L (49.5-127.3), tazobactam was 9.5 mg/L (6.3-14.2), and vancomycin was 14.3 mg/L (11.6-21.8). Trough concentrations failed to meet optimal higher limits in 26%, 36%, and 72% and optimal lower limits in 4%, 4%, and 55% of patients for meropenem, piperacillin, and vancomycin, respectively. CONCLUSIONS: In critically ill patients treated with RRT, antibiotic dosing regimens, RRT prescription, and eTRCL varied markedly and resulted in highly variable antibiotic concentrations that failed to meet therapeutic targets in many patients.


Assuntos
Antibacterianos , Estado Terminal , Antibacterianos/uso terapêutico , Humanos , Meropeném , Piperacilina , Estudos Prospectivos , Terapia de Substituição Renal
16.
Angew Chem Int Ed Engl ; 60(19): 10542-10546, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33689214

RESUMO

With annual production at >85 million tons/year, ethanol is the world's largest-volume renewable small molecule carbon source, yet its use as a C2 -feedstock in enantioselective C-C coupling is unknown. Here, the first catalytic enantioselective C-C couplings of ethanol are demonstrated in reactions with structurally complex, nitrogen-rich allylic acetates incorporating the top 10 N-heterocycles found in FDA-approved drugs.


Assuntos
Alcenos/química , Etanol/síntese química , Irídio/química , Catálise , Etanol/química , Estrutura Molecular , Estereoisomerismo
17.
Angew Chem Int Ed Engl ; 58(40): 14055-14064, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31162793

RESUMO

Use of abundant feedstock pronucleophiles in catalytic carbonyl reductive coupling enhances efficiency in target-oriented synthesis. For such reactions, equally inexpensive reductants are desired or, ideally, corresponding hydrogen autotransfer processes may be enacted wherein alcohols serve dually as reductant and carbonyl proelectrophile. As described in this Minireview, these concepts allow reactions that traditionally require preformed organometallic reagents to be conducted catalytically in a byproduct-free manner from inexpensive π-unsaturated precursors.

18.
Br J Dermatol ; 176(5): 1345-1350, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27534273

RESUMO

The inherited palmoplantar keratodermas (PPKs) are a heterogeneous group of genodermatoses, characterized by thickening of the epidermis of the palms and soles. No classification system satisfactorily unites clinical presentation, pathology and molecular pathogenesis. There are four patterns of hyperkeratosis - striate, focal, diffuse and punctate. Mutations in the desmoglein 1 gene (DSG1), a transmembrane glycoprotein, have been reported primarily in striate, but also in focal and diffuse PPKs. We report seven unrelated pedigrees with dominantly inherited PPK owing to mutations in the DSG1 gene, with marked phenotypic variation. Genomic DNA from each family was isolated, and individual exons amplified by polymerase chain reaction. Sanger sequencing was employed to identify mutations. Mutation analysis identified novel mutations in five families (p.Tyr126Hisfs*2, p.Ser521Tyrfs*2, p.Trp3*, p.Asp591Phefs*9 and p.Met249Ilefs*6) with striate palmar involvement and varying focal or diffuse plantar disease, and the recurrent mutation c.76C>T, p.Arg26*, in two families with variable PPK patterns. We report one recurrent and five novel DSG1 mutations, causing varying patterns of PPK, highlighting the clinical heterogeneity arising from mutations in this gene.


Assuntos
Desmogleína 1/genética , Ceratodermia Palmar e Plantar/genética , Mutação/genética , África/etnologia , América/etnologia , Europa (Continente)/etnologia , Feminino , Testes Genéticos , Humanos , Masculino , Linhagem , Fenótipo , Adulto Jovem
19.
Clin Exp Dermatol ; 41(8): 884-889, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27786367

RESUMO

Congenital abnormalities of the nail are rare conditions that are most frequently associated with congenital ectodermal syndromes involving several of the epidermal appendages including the skin, teeth, hair and nails. Isolated recessive nail dysplasia (IRND) is much rarer but has recently been recognized as a condition resulting in 20-nail dystrophy in the absence of other cutaneous or extracutaneous findings. A few case reports have identified mutations in the Frizzled 6 (FZD6) gene in families presenting with abnormal nails consistent with IRND. These reports have highlighted the role of Wnt-FZD signalling in the process of nail formation. We report three families presenting with features of IRND, in whom we identified mutations in FZD6, including one previously unreported mutation.


Assuntos
Receptores Frizzled/genética , Mutação , Doenças da Unha/congênito , Unhas Malformadas/genética , Pré-Escolar , Feminino , Humanos , Masculino , Doenças da Unha/complicações , Doenças da Unha/etiologia , Doenças da Unha/genética , Unhas Malformadas/etiologia
20.
Br J Cancer ; 110(5): 1189-98, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24518598

RESUMO

BACKGROUND: The NUT midline carcinoma (NMC) is a rare but fatal cancer for which systematic testing of therapy options has never been performed. METHODS: On the basis of disease biology, we compared the efficacy of the CDK9 inhibitor flavopiridol (FP) with a panel of anticancer agents in NMC cell lines and mouse xenografts. RESULTS: In vitro anthracyclines, topoisomerase inhibitors, and microtubule poisons were among the most cytotoxic drug classes for NMC cells, while efficacy of the bromodomain inhibitor JQ1 varied considerably between lines carrying different BRD4 (bromodomain-containing protein 4)-NUT (nuclear protein in testis) translocations. Efficacy of FP was comparable to vincristine and doxorubicin, drugs that have been previously used in NMC patients. All three compounds showed significantly better activity than etoposide and vorinostat, agents that have also been used in NMC patients. Statins and antimetabolites demonstrated intermediate single-agent efficacy. In vivo, vincristine significantly inhibited tumour growth in two different NMC xenografts. Flavopiridol in vivo was significantly effective in one of the two NMC xenograft lines, demonstrating the biological heterogeneity of this disease. CONCLUSIONS: These results demonstrate that FP may be of benefit to a subset of patients with NMC, and warrant a continued emphasis on microtubule inhibitors, anthracyclines, and topoisomerase inhibitors as effective drug classes in this disease.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Flavonoides/farmacologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Piperidinas/farmacologia , Animais , Antraciclinas/farmacologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Inibidores da Topoisomerase/farmacologia , Moduladores de Tubulina/farmacologia , Vincristina/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
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