Step-economic total synthesis of melosatin a from eugeno

An efficient and straightforward route toward the isatin-type natural product melosatin A is reported, employing a trisubstituted aniline as a key intermediate. The latter was synthesized in 4 steps and 60% overall yield from eugenol, through its regioselective nitration, sequentially followed by a Williamson methylation, an olefin cross-metathesis with 4-phenyl-1-butene and the simultaneous reduction of olefin and nitro groups. The final step, a Martinet cyclocondensation of the key aniline with diethyl 2-ketomalonate, provided the natural product with 68% yield.Fil: Bolivar Ávila, Santiago J. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario (IQUIR-CONICET); Argentina.Fil: Ledesma, Gabriela N. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario (IQUIR-CONICET); Argentina.Fil: Kaufman, Teodoro Saúl. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario (IQUIR-CONICET); Argentina.Fil: Testero, Sebastián A. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario (IQUIR-CONICET); Argentina.Fil: Larghi, Enrique Leandro. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario (IQUIR-CONICET); Argentina

SARS-CoV2 RNA detection in a pancreatic pseudocyst sample

The involvement of gastrointestinal system in SARS-CoV2 related disease, COVID-19, is increasingly recognized. COVID-19 associated pancreatic injury has been suggested, but its correlation with pancreatic disease is still unclear. In this case report, we describe the detection of SARS-CoV2 RNA in a pancreatic pseudocyst fluid sample collected from a patient with SARS-CoV2 associated pneumonia and a pancreatic pseudocyst developed as a complication of an acute edematous pancreatitis. The detection of SARS-CoV2 within the pancreatic collection arise the question of whether this virus has a tropism for pancreatic tissue and whether it plays a role in pancreatic diseases occurrence

Absolute configuration of clemateol

The present study reports the determination of absolute stereochemistry of clemateol, an irregular monoterpene containing an epoxy group, which was isolated as the main component from the essential oil of Calea clematidea (Asteraceae). Its absolute stereochemistry was unambiguously established on the basis of detailed nuclear magnetic resonance (NMR) spectroscopic evidence (3JH-H analysis, derivatization as Mosher's esters and nuclear Overhauser effect (NOESY) spectrum) and also by resonance scattering effects in the single crystal X-ray diffraction (XRD) resolution of its (R)-mandelic acid ester derivative.Fil: Pedroso, Marcelo. Universidade Federal de Santa Maria; BrasilFil: Gehn, Adriana Z.. Universidade Federal de Santa Maria; BrasilFil: Stivanin, Mateus L.. Universidade Federal de Santa Maria; BrasilFil: Larghi, Enrique Leandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Burrow, Robert A.. Universidade Federal de Santa Maria; BrasilFil: Resende, Jackson A. L. C.. Universidade Federal Fluminense; BrasilFil: Da Silva, Ubiratan F.. Universidade Federal de Santa Maria; BrasilFil: Mostardeiro, Marco A.. Universidade Federal de Santa Maria; BrasilFil: Dalcol, Ionara I.. Universidade Federal de Santa Maria; BrasilFil: Morel, Ademir F.. Universidade Federal de Santa Maria; Brasi

Evaluacion de un conjugado antirrabico por titulacion en diferentes microscopios fluorescentes

En cinco laboratorios se tituló una partida de conjugado antirrábico para inmunofluoresCencia con microscopios de tres marcas distintas, equipados con diferentes accesorios. Los títulos obtenidos variaron entre < 1:4 y 1:64, dependiendo de los accesorios utilizados. Estos resultados ponen de relieve la necesidad de titular los conjugados en cada laboratorio. Se mencionam los inconvenientes que pueden ocasionar la distribución del reactivo diluido de acuerdo con el título obtenido por el productor, o mezclado con suspensiones de cerebro de ratones normales e infectados con virus rábico

Quantitative phosphoproteomics of cytotoxic T cells to reveal Protein Kinase D 2 regulated networks

The focus of the present study was to characterize the phosphoproteome of cytotoxic T cells and to explore the role of the serine threonine kinase PKD2 (Protein Kinase D2) in the phosphorylation networks of this key lymphocyte population. We used Stable Isotope Labeling of Amino acids in Culture (SILAC) combined with phosphopeptide enrichment and quantitative mass-spectrometry to determine the impact of PKD2 loss on the cytotoxic T cells phosphoproteome. We identified 15,871 phosphorylations on 3505 proteins in cytotoxic T cells. 450 phosphosites on 281 proteins were down-regulated and 300 phosphosites on 196 proteins were up-regulated in PKD2 null cytotoxic T cells. These data give valuable new insights about the protein phosphorylation networks operational in effector T cells and reveal that PKD2 regulates directly and indirectly about 5% of the cytotoxic T-cell phosphoproteome. PKD2 candidate substrates identified in this study include proteins involved in two distinct biological functions: regulation of protein sorting and intracellular vesicle trafficking, and control of chromatin structure, transcription, and translation. In other cell types, PKD substrates include class II histone deacetylases such as HDAC7 and actin regulatory proteins such as Slingshot. The current data show these are not PKD substrates in primary T cells revealing that the functional role of PKD isoforms is different in different cell lineages

Impact of biliary stents on the diagnostic accuracy of EUS-guided fine-needle biopsy of solid pancreatic head lesions: A multicenter study

There is no clear evidence of a negative impact of biliary stents on the diagnostic yield of EUS-guided fine-needle biopsy (EUS-FNB) for diagnosing pancreatic head lesions. We aimed to evaluate the association between the presence of biliary stents and the diagnostic accuracy of EUS-FNB. Materials and Methods: A multicenter retrospective study including all jaundiced patients secondary to pancreatic head masses was performed. Patients were divided into two groups according to the presence of a biliary stent placed before EUS-FNB. Pathological results were classified according to the Papanicolaou classification and compared against the final diagnosis. Diagnostic measures in the two groups were compared. Multivariate logistic regression analyses including potential factors affecting EUS-FNB accuracy were performed. Results: Overall, 842 patients were included, 495 (58.8%) without and 347 (41.2%) with biliary stent. A plastic or a metal stent was placed in 217 (62.5%) and 130 (37.5%) cases, respectively. Diagnostic sensitivity and accuracy were significantly higher in patients without biliary stent than in those with stent (91.9% and 92.1% vs. 85.9% and 86.4%, P = 0.010 At multivariate analyses, lesion size (odds ratio [OR]: 1.05, 95% confidence interval [CI]: 1.02-1.09, P = 0.01) and presence of biliary stent (OR: 0.51, 95% CI: 0.32-0.89, P = 0.01) were independently associated with diagnostic accuracy. In the subgroup of patients with biliary stent, the type of stent (plastic vs. metal) did not impact EUS-FNB yield, whereas the use of larger bore needles enhanced diagnostic accuracy (OR: 2.29, 95% CI: 1.28-4.12, P = 0.005). Conclusions: In this large retrospective study, an indwelling biliary stent negatively impacted the diagnostic accuracy of EUS-FNB. Preferably, EUS-FNB should precede endoscopic retrograde cholangiopancreatography, especially in the case of small tumors

Langmuir-Blodgett monolayers holding a wound healing active compound and its effect in cell culture. A model for the study of surface mediated drug delivery systems

Langmuir and Langmuir-Blodgett films holding a synthetic bioinspired wound healing active compound were used as drug-delivery platforms. Palmitic acid Langmuir monolayers were able to incorporate 2-methyltriclisine, a synthetic Triclisine derivative that showed wound healing activity. The layers proved to be stable and the nanocomposites were transferred to solid substrates. Normal human lung cells (Medical Research Council cell strain 5, MRC-5) were grown over the monomolecular Langmuir-Blodgett films that acted as a drug reservoir and delivery system. The proliferation and migration of the cells were clearly affected by the presence of 2-methyltriclisine in the amphiphilic layers. The methodology is proposed as a simple and reliable model for the study of the effects of bioactive compounds over cellular cultures.EEA Marcos JuárezFil: Fernández, Luciana. Universidad Nacional de Río Cuarto. Departamento de Física y Departamento de Química; ArgentinaFil: Fernández, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Reviglio, Ana Lucía. Universidad Nacional de Río Cuarto. Departamento de Física y Departamento de Química; ArgentinaFil: Reviglio, Ana Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Heredia, Daniel A. Universidad Nacional de Río Cuarto. Departamento de Física y Departamento de Química; Argentina.Fil: Heredia, Daniel A. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Morales, Gustavo M. Universidad Nacional de Río Cuarto. Departamento de Física y Departamento de Química; ArgentinaFil: Morales, Gustavo M. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Santo, Marisa. Universidad Nacional de Río Cuarto. Departamento de Física y Departamento de Química; ArgentinaFil: Santo, Marisa. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Otero, Luis. Universidad Nacional de Río Cuarto. Departamento de Física y Departamento de Química; ArgentinaFil: Otero, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alustiza, Fabrisio Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez; ArgentinaFil: Liaudat, Ana Cecilia. Universidad Nacional de Río Cuarto. Departamento de Biología Molecular; ArgentinaFil: Bosch, Pablo. Universidad Nacional de Río Cuarto. Departamento de Biología Molecular; ArgentinaFil: Larghi, Enrique L. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Bracca, Andrea B.J. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Kaufman, Teodoro S. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; Argentin

Nonnegative rank-preserving operators

AbstractAnalogues of characterizations of rank-preserving operators on field-valued matrices are determined for matrices witheentries in certain structures S contained in the nonnegative reals. For example, if S is the set of nonnegative members of a real unique factorization domain (e.g. the nonnegative reals or the nonnegative integers), M is the set of m×n matrices with entries in S, and min(m,n)⩾4, then a “linear” operator on M preserves the “rank” of each matrix in M if and only if it preserves the ranks of those matrices in M of ranks 1, 2, and 4. Notions of rank and linearity are defined analogously to the field-valued concepts. Other characterizations of rank-preserving operators for matrices over these and other structures S are also given