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1.
Nature ; 629(8013): 937-944, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38720067

RESUMO

QS-21 is a potent vaccine adjuvant and remains the only saponin-based adjuvant that has been clinically approved for use in humans1,2. However, owing to the complex structure of QS-21, its availability is limited. Today, the supply depends on laborious extraction from the Chilean soapbark tree or on low-yielding total chemical synthesis3,4. Here we demonstrate the complete biosynthesis of QS-21 and its precursors, as well as structural derivatives, in engineered yeast strains. The successful biosynthesis in yeast requires fine-tuning of the host's native pathway fluxes, as well as the functional and balanced expression of 38 heterologous enzymes. The required biosynthetic pathway spans seven enzyme families-a terpene synthase, P450s, nucleotide sugar synthases, glycosyltransferases, a coenzyme A ligase, acyl transferases and polyketide synthases-from six organisms, and mimics in yeast the subcellular compartmentalization of plants from the endoplasmic reticulum membrane to the cytosol. Finally, by taking advantage of the promiscuity of certain pathway enzymes, we produced structural analogues of QS-21 using this biosynthetic platform. This microbial production scheme will allow for the future establishment of a structure-activity relationship, and will thus enable the rational design of potent vaccine adjuvants.


Assuntos
Adjuvantes Imunológicos , Engenharia Metabólica , Saccharomyces cerevisiae , Saponinas , Adjuvantes Imunológicos/biossíntese , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/genética , Adjuvantes Imunológicos/metabolismo , Vias Biossintéticas/genética , Desenho de Fármacos , Enzimas/genética , Enzimas/metabolismo , Engenharia Metabólica/métodos , Plantas/enzimologia , Plantas/genética , Plantas/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saponinas/biossíntese , Saponinas/química , Saponinas/genética , Saponinas/metabolismo , Relação Estrutura-Atividade
2.
Proc Natl Acad Sci U S A ; 120(50): e2312484120, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38060556

RESUMO

We present a hybrid scheme based on classical density functional theory and machine learning for determining the equilibrium structure and thermodynamics of inhomogeneous fluids. The exact functional map from the density profile to the one-body direct correlation function is represented locally by a deep neural network. We substantiate the general framework for the hard sphere fluid and use grand canonical Monte Carlo simulation data of systems in randomized external environments during training and as reference. Functional calculus is implemented on the basis of the neural network to access higher-order correlation functions via automatic differentiation and the free energy via functional line integration. Thermal Noether sum rules are validated explicitly. We demonstrate the use of the neural functional in the self-consistent calculation of density profiles. The results outperform those from state-of-the-art fundamental measure density functional theory. The low cost of solving an associated Euler-Lagrange equation allows to bridge the gap from the system size of the original training data to macroscopic predictions upon maintaining near-simulation microscopic precision. These results establish the machine learning of functionals as an effective tool in the multiscale description of soft matter.

3.
Nature ; 568(7750): 108-111, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30918404

RESUMO

Ethane is the second most abundant component of natural gas in addition to methane, and-similar to methane-is chemically unreactive. The biological consumption of ethane under anoxic conditions was suggested by geochemical profiles at marine hydrocarbon seeps1-3, and through ethane-dependent sulfate reduction in slurries4-7. Nevertheless, the microorganisms and reactions that catalyse this process have to date remained unknown8. Here we describe ethane-oxidizing archaea that were obtained by specific enrichment over ten years, and analyse these archaea using phylogeny-based fluorescence analyses, proteogenomics and metabolite studies. The co-culture, which oxidized ethane completely while reducing sulfate to sulfide, was dominated by an archaeon that we name 'Candidatus Argoarchaeum ethanivorans'; other members were sulfate-reducing Deltaproteobacteria. The genome of Ca. Argoarchaeum contains all of the genes that are necessary for a functional methyl-coenzyme M reductase, and all subunits were detected in protein extracts. Accordingly, ethyl-coenzyme M (ethyl-CoM) was identified as an intermediate by liquid chromatography-tandem mass spectrometry. This indicated that Ca. Argoarchaeum initiates ethane oxidation by ethyl-CoM formation, analogous to the recently described butane activation by 'Candidatus Syntrophoarchaeum'9. Proteogenomics further suggests that oxidation of intermediary acetyl-CoA to CO2 occurs through the oxidative Wood-Ljungdahl pathway. The identification of an archaeon that uses ethane (C2H6) fills a gap in our knowledge of microorganisms that specifically oxidize members of the homologous alkane series (CnH2n+2) without oxygen. Detection of phylogenetic and functional gene markers related to those of Ca. Argoarchaeum at deep-sea gas seeps10-12 suggests that archaea that are able to oxidize ethane through ethyl-CoM are widespread members of the local communities fostered by venting gaseous alkanes around these seeps.


Assuntos
Organismos Aquáticos/metabolismo , Archaea/metabolismo , Etano/metabolismo , Anaerobiose , Archaea/classificação , Archaea/enzimologia , Archaea/genética , Deltaproteobacteria/metabolismo , Etano/química , Gases/química , Gases/metabolismo , Golfo do México , Metano/biossíntese , Oxirredução , Oxirredutases/genética , Oxirredutases/isolamento & purificação , Oxirredutases/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Sulfatos/metabolismo , Sulfetos/metabolismo
4.
Phys Rev Lett ; 133(9): 098201, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39270167

RESUMO

We present a scheme for investigating arbitrary thermal observables in spatially inhomogeneous equilibrium many-body systems. Extending the grand canonical ensemble yields any given observable as an explicit hyperdensity functional. Associated local fluctuation profiles follow from an exact hyper-Ornstein-Zernike equation. While the local compressibility and simple observables permit analytic treatment, complex order parameters are accessible via simulation-based supervised machine learning of neural hyperdirect correlation functionals. We exemplify efficient and accurate neural predictions for the cluster statistics of hard rods, square-well rods, and hard spheres. The theory allows one to treat complex observables, as is impossible in standard density functional theory.

5.
Bioorg Chem ; 153: 107887, 2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39423771

RESUMO

Class I HDACs are considered promising targets for cancer due to their role in epigenetic modifications. The main challenges in developing a new, potent and non-toxic class I HDAC inhibitor are selectivity and appropriate pharmacokinetics. The PROTAC technique (Proteolysis Targeting Chimera) is a new method in drug development for the production of active substances that can degrade a protein of interest (POI) instead of inhibiting it. This technique will open the era to produce selective and potent drugs with a high margin of safety. Previously, we reported different inhibitors targeting class I HDACs functionalized with aminobenzamide or hydroxamate groups. In the current research work, we will employ PROTAC technique to develop class I HDAC degraders based on our previously reported inhibitors. We synthesized two series of aminobenzamide-based PROTACs and hydroxamate-based PROTACs and tested them in vitro against class I HDACs. To ensure their degradation, all of them were screened against HDAC2 as representative example of class I. The best candidates were evaluated at different concentrations at various HDAC subtypes. This resulted in the PROTAC (32a) (HI31.1) that degrades HDAC8 with a DC50 of 8.9 nM with a proper margin of selectivity against other isozymes. Moreover, PROTAC 32a is able to degrade HDAC6 with DC50 = 14.3 nM. Apoptotic study on leukemic cells (MV-4-11) displayed more than 50 % apoptosis took place at 100 nM. PROTAC 32a (HI31.1) showed a good margin of safety against normal cell line and proper chemical stability.

6.
Arch Pharm (Weinheim) ; : e2400437, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39291901

RESUMO

Class I histone deacetylases (HDACs) are considered promising targets in current cancer research. To obtain subtype-selective and potent HDAC inhibitors, we used the aminobenzamide scaffold as the zinc-binding group and prepared new derivatives with a pyrazole ring as the linking group. The synthesized compounds were analyzed in vitro using an enzymatic assay against HDAC1, -2, and -3. Compounds 12b, 15b, and 15i were found to be potent HDAC1 inhibitors, also in comparison to the reference compounds entinostat and tacedinaline, with IC50 values of 0.93, 0.22, and 0.68 µM, respectively. The best compounds were measured for their cellular effect and target engagement in acute myeloid leukemia (AML) cells. In addition, we studied the interaction of the compounds with HDAC subtypes using docking and molecular dynamic simulations. In summary, we have developed a new chemotype of HDAC1 inhibitors that can be used for further structure-based optimization.

7.
Int J Mol Sci ; 25(19)2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39409066

RESUMO

Preliminary studies on a radioactive antibody against the neural cell adhesion molecule (NCAM) demonstrated a significant accumulation of [131I]I-ERIC1 in neuroblastoma tumor cells in mice. This study aims to validate the therapeutic efficacy and potential adverse effects of these radioactive immunoconjugates (RICs) in neuroblastoma-bearing mice. To determine the highest tolerated dose, healthy SCID mice received 1 to 22 MBq of [131I]I-ERIC1, with the survival time measured. Tumor response was evaluated by administering 0.8 to 22 MBq of [131I]I-ERIC1 to neuroblastoma-bearing mice and assessing tumor size and systemic toxicity through body weight, blood counts, and survival. It was observed that doses up to approximately 3 MBq per animal (150 MBq/kg) were well tolerated, whereas higher doses resulted in systemic toxicity and death. The neuroblastomas exhibited a dose-dependent response, with optimal therapeutic efficacy achieved at 1.8-2.5 MBq per animal (90-125 MBq/kg), significantly extending survival by a factor of five. The antibody ERIC1 is a promising vehicle for the transport of beta emitters into NCAM-positive tumor tissue. An optimal dosage of the [131I]I-ERIC1 antibody can be established with a balance of tumor-static effects and adverse effects, resulting in a marked extension of survival time.


Assuntos
Radioisótopos do Iodo , Neuroblastoma , Animais , Neuroblastoma/patologia , Neuroblastoma/metabolismo , Neuroblastoma/tratamento farmacológico , Camundongos , Radioisótopos do Iodo/efeitos adversos , Linhagem Celular Tumoral , Moléculas de Adesão de Célula Nervosa/metabolismo , Humanos , Camundongos SCID , Ensaios Antitumorais Modelo de Xenoenxerto , Imunoconjugados/farmacologia , Feminino , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/farmacologia
8.
Can Assoc Radiol J ; : 8465371241290762, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39437341

RESUMO

The Canadian Association of Radiologists (CAR) Spine Expert Panel is made up of physicians from the disciplines of radiology, emergency medicine, neurology, neurosurgery, physiatry, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 10 clinical/diagnostic scenarios, a rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for one or more of these clinical/diagnostic scenarios. Recommendations from 23 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) for guidelines framework were used to develop 22 recommendation statements across the 8 scenarios (one scenario points to the CAR Trauma Referral Guideline and one scenario points to the CAR Musculoskeletal Guideline). This guideline presents the methods of development and the referral recommendations for myelopathy, suspected spinal infection, possible atlanto-axial instability (non-traumatic), axial pain (non-traumatic), radicular pain (non-traumatic), cauda equina syndrome, suspected spinal tumour, and suspected compression fracture. Spondyloarthropathies and spine trauma point to other CAR Diagnostic Imaging Referral Guidelines, Musculoskeletal and Trauma, respectively.

9.
J Am Chem Soc ; 145(16): 8822-8832, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37057992

RESUMO

Modular polyketide synthases (PKSs) are polymerases that employ α-carboxyacyl-CoAs as extender substrates. This enzyme family contains several catalytic modules, where each module is responsible for a single round of polyketide chain extension. Although PKS modules typically use malonyl-CoA or methylmalonyl-CoA for chain elongation, many other malonyl-CoA analogues are used to diversify polyketide structures in nature. Previously, we developed a method to alter an extension substrate of a given module by exchanging an acyltransferase (AT) domain while maintaining protein folding. Here, we report in vitro polyketide biosynthesis by 13 PKSs (the wild-type PKS and 12 AT-exchanged PKSs with unusual ATs) and 14 extender substrates. Our ∼200 in vitro reactions resulted in 13 structurally different polyketides, including several polyketides that have not been reported. In some cases, AT-exchanged PKSs produced target polyketides by >100-fold compared to the wild-type PKS. These data also indicate that most unusual AT domains do not incorporate malonyl-CoA and methylmalonyl-CoA but incorporate various rare extender substrates that are equal to in size or slightly larger than natural substrates. We developed a computational workflow to predict the approximate AT substrate range based on active site volumes to support the selection of ATs. These results greatly enhance our understanding of rare AT domains and demonstrate the benefit of using the proposed PKS engineering strategy to produce novel chemicals in vitro.


Assuntos
Policetídeo Sintases , Policetídeos , Policetídeo Sintases/metabolismo , Aciltransferases/química , Domínio Catalítico , Policetídeos/metabolismo , Especificidade por Substrato
10.
Phys Rev Lett ; 130(26): 268203, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37450808

RESUMO

Liquid structure carries deep imprints of an inherent thermal invariance against a spatial transformation of the underlying classical many-body Hamiltonian. At first order in the transformation field Noether's theorem yields the local force balance. Three distinct two-body correlation functions emerge at second order, namely the standard two-body density, the localized force-force correlation function, and the localized force gradient. An exact Noether sum rule interrelates these correlators. Simulations of Lennard-Jones, Yukawa, soft-sphere dipolar, Stockmayer, Gay-Berne and Weeks-Chandler-Andersen liquids, of monatomic water and of a colloidal gel former demonstrate the fundamental role in the characterization of spatial structure.

11.
Horm Metab Res ; 55(11): 765-770, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37903497

RESUMO

COVID-19 has severely affected the delivery of surgical care worldwide. The aim of the present study was to evaluate its impact on adrenal surgery at our academic endocrine center. All primary adrenal surgeries performed at the University Hospital of Cologne, Germany between 01.01.2019 and 31.07.2022 were included. This time frame was divided into pre-Covid (before 02/20), acute Covid (until 05/21), and post acute period (after 05/2021). Demographics, clinic-pathologic characteristics and treatment of these patients were analyzed. One hundred adrenalectomies were included: 22 before, 30 during, and 48 after the acute phase. The percentage of Conn adenomas and pheochromocytomas decreased during the acute phase (from 45.4 to 26.6% and from 18 to 10%, respectively) in favor of Cushing adenomas and suspicious tumors (from 4.5 to 20% and from 31.8 to 36.6%). About 90.9% of tumors resected for suspicion of malignancy were confirmed malignant by final histopathology, as opposed to 71.4% and 52.6% before and after the acute phase. The operative technique was similar during the three phases (63% retroperitoneoscopic, 34% laparoscopic and 2% open resections), with a significantly shorter operative time for retroperitoneoscopy (p=0.04). ICU monitoring demand increased during the acute phase (from 13.6% to 43.3%), according to the increase in Cushing adenomas and malignant tumors. During the acute phase of COVID-19 pandemic adrenal surgery for Cushing and malignant tumors increased, while a delay in pheochromocytoma surgery to the post acute phase was observed. The suspicion of malignancy formulated by the endocrine tumor board was accurate in 90.9% of cases.


Assuntos
Adenoma , Neoplasias das Glândulas Suprarrenais , COVID-19 , Laparoscopia , Feocromocitoma , Humanos , Pandemias , COVID-19/epidemiologia , Neoplasias das Glândulas Suprarrenais/epidemiologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/patologia , Adrenalectomia , Feocromocitoma/epidemiologia , Feocromocitoma/cirurgia , Feocromocitoma/patologia , Adenoma/epidemiologia , Adenoma/cirurgia , Laparoscopia/métodos
12.
Soft Matter ; 19(12): 2214-2223, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36883340

RESUMO

We study theoretically the effect of a gravitational field on the equilibrium behaviour of a colloidal suspension of rods with different length-to-width aspect ratios. The bulk phases of the system are described with analytical equations of state. The gravitational field is then incorporated via sedimentation path theory, which assumes a local equilibrium condition at each altitude of the sample. The bulk phenomenology is significantly enriched by the presence of the gravitational field. In a suspension of elongated rods with five stable phases in bulk, the gravitational field stabilizes up to fifteen different stacking sequences. The sample height has a non-trivial effect on the stable stacking sequence. New layers of distinct bulk phases appear either at the top, at the bottom, or simultaneously at the top and the bottom when increasing the sample height at constant colloidal concentration. We also study sedimentation in a mass-polydisperse suspension in which all rods have the same shape but different buoyant masses.

13.
J Chem Phys ; 158(5): 054908, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36754804

RESUMO

We investigate the stationary flow of a colloidal gel under an inhomogeneous external shear force using adaptive Brownian dynamics simulations. The interparticle forces are derived from the Stillinger-Weber potential, where the three-body term is tuned to enable network formation and gelation in equilibrium. When subjected to the shear force field, the system develops remarkable modulations in the one-body density profile. Depending on the shear magnitude, particles accumulate either in quiescent regions or in the vicinity of maximum net flow, and we deduce this strong non-equilibrium response to be characteristic of the gel state. Studying the components of the internal force parallel and perpendicular to the flow direction reveals that the emerging flow and structure of the stationary state are driven by significant viscous and structural superadiabatic forces. Thereby, the magnitude and nature of the observed non-equilibrium phenomena differ from the corresponding behavior of simple fluids. We demonstrate that a simple power functional theory reproduces accurately the viscous force profile, giving a rationale of the complex dynamical behavior of the system.

14.
Environ Microbiol ; 24(2): 583-595, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34190386

RESUMO

Carbon and hydrogen stable isotope effects associated with methane formation by the corrosive archaeon Methanobacterium strain IM1 were determined during growth with hydrogen and iron. Isotope analyses were complemented by structural, elemental and molecular composition analyses of corrosion crusts. During growth with H2 , strain IM1 formed methane with average δ13 C of -43.5‰ and δ2 H of -370‰. Corrosive growth led to methane more depleted in 13 C, with average δ13 C ranging from -56‰ to -64‰ during the early and the late growth phase respectively. The corresponding δ2 H were less impacted by the growth phase, with average values ranging from -316 to -329‰. The stable isotope fractionation factors, α 13 C CO 2 / CH 4 , were 1.026 and 1.042 for hydrogenotrophic and corrosive growth respectively. Corrosion crusts formed by strain IM1 have a domed structure, appeared electrically conductive and were composed of siderite, calcite and iron sulfide, the latter formed by precipitation of sulfide (from culture medium) with ferrous iron generated during corrosion. Strain IM1 cells were found attached to crust surfaces and encrusted deep inside crust domes. Our results may assist to diagnose methanogens-induced corrosion in the field and suggest that intrusion of sulfide in anoxic settings may stimulate corrosion by methanogenic archaea via formation of semiconductive crusts.


Assuntos
Archaea , Euryarchaeota , Isótopos de Carbono/análise , Corrosão , Ferro , Isótopos , Metano
15.
Appl Environ Microbiol ; 88(7): e0243021, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35285712

RESUMO

Pseudomonas putida KT2440 has long been studied for its diverse and robust metabolisms, yet many genes and proteins imparting these growth capacities remain uncharacterized. Using pooled mutant fitness assays, we identified genes and proteins involved in the assimilation of 52 different nitrogen containing compounds. To assay amino acid biosynthesis, 19 amino acid drop-out conditions were also tested. From these 71 conditions, significant fitness phenotypes were elicited in 672 different genes including 100 transcriptional regulators and 112 transport-related proteins. We divide these conditions into 6 classes, and propose assimilatory pathways for the compounds based on this wealth of genetic data. To complement these data, we characterize the substrate range of three promiscuous aminotransferases relevant to metabolic engineering efforts in vitro. Furthermore, we examine the specificity of five transcriptional regulators, explaining some fitness data results and exploring their potential to be developed into useful synthetic biology tools. In addition, we use manifold learning to create an interactive visualization tool for interpreting our BarSeq data, which will improve the accessibility and utility of this work to other researchers. IMPORTANCE Understanding the genetic basis of P. putida's diverse metabolism is imperative for us to reach its full potential as a host for metabolic engineering. Many target molecules of the bioeconomy and their precursors contain nitrogen. This study provides functional evidence linking hundreds of genes to their roles in the metabolism of nitrogenous compounds, and provides an interactive tool for visualizing these data. We further characterize several aminotransferases, lactamases, and regulators, which are of particular interest for metabolic engineering.


Assuntos
Pseudomonas putida , Aminoácidos/metabolismo , Nitrogênio/metabolismo , Fenótipo , Pseudomonas putida/metabolismo , Transaminases/genética , Transaminases/metabolismo
16.
Phys Rev Lett ; 128(9): 094502, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302832

RESUMO

Inhomogeneities in the velocity field of a moving fluid are dampened by the inherent viscous behavior of the system. Both bulk and shear effects, related to the divergence and the curl of the velocity field, are relevant. On molecular time scales, beyond the Navier-Stokes description, memory plays an important role. Using molecular and overdamped Brownian dynamics many-body simulations, we demonstrate that analogous viscous effects act on the acceleration field. This acceleration viscous behavior is associated with the divergence and the curl of the acceleration field, and it can be quantitatively described using simple exponentially decaying memory kernels. The simultaneous use of velocity and acceleration fields enables the description of fast dynamics on molecular scales.

17.
Horm Metab Res ; 54(5): 294-299, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35533674

RESUMO

Work up of adrenal masses includes assessment of endocrine activity and malignancy risk. There is no indication for surgical removal of nonfunctional adrenal adenomas, according to the guidelines. In the present study, we aimed at evaluating the impact of a university endocrine tumor board on the quality of the indications for adrenal surgery at our institution. One hundred consecutive patients receiving primary adrenal surgery at the University Hospital of Cologne, Germany were included. Their demographics, clinic-pathologic characteristics, treatment and outcome were analyzed. In 55 (55%) cases, indication for surgery consisted in functional benign tumors, including Conn, Cushing adenomas and pheochromocytomas. Forty (40%) tumors were referred to surgery for malignancy suspicion and 5 (5%) myelolipomas were removed due to their size. Eighty-nine percent of surgeries were performed as minimally invasive procedures. Overall morbidity included two (2%) self-limiting pancreatic fistulas after left laparoscopic adrenalectomy for pheochromocytoma. All functional tumors were confirmed benign by final histology. Only 33 (82.5%) of 40 suspicious cases turned out to be malignant. Consequently, nonfunctional benign adenomas were "unnecessarily" removed in only 7 (7%) patients, with 6 (85.7%) of them having a history of extra-adrenal cancer and all of them fulfilling criteria for surgery, according to the international guidelines. In conclusion, the endocrine tumor board provided an excellent adherence to the guidelines with most surgeries being performed either for functional or malignant tumors. In nonfunctional tumors with history of extra adrenal cancer, CT guided biopsy might be considered for obviating surgery.


Assuntos
Adenoma , Neoplasias das Glândulas Suprarrenais , Laparoscopia , Feocromocitoma , Adenoma/patologia , Neoplasias das Glândulas Suprarrenais/patologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia , Humanos , Laparoscopia/métodos , Feocromocitoma/patologia , Feocromocitoma/cirurgia
18.
J Chem Phys ; 157(23): 234901, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36550036

RESUMO

Both polydispersity and the presence of a gravitational field are inherent to essentially any colloidal experiment. While several theoretical works have focused on the effect of polydispersity on the bulk phase behavior of a colloidal system, little is known about the effect of a gravitational field on a polydisperse colloidal suspension. We extend here the sedimentation path theory to study sedimentation-diffusion-equilibrium of a mass-polydisperse colloidal system: the particles possess different buoyant masses but they are otherwise identical. The model helps to understand the interplay between gravity and polydispersity on sedimentation experiments. Since the theory can be applied to any parent distribution of buoyant masses, it can also be used to study the sedimentation of monodisperse colloidal systems. We find that mass-polydispersity has a strong influence in colloidal systems near density matching for which the bare density of the colloidal particles equals the solvent density. To illustrate the theory, we study crystallization in sedimentation-diffusion-equilibrium of a suspension of mass-polydisperse hard spheres.

19.
Endocr Regul ; 56(3): 227-231, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35843718

RESUMO

Objective. The present study evaluates the occurrence of subacute thyroiditis in temporal connection with SARS-Cov2 vaccinations described in the literature last year and confirmed by our clinical routine. Methods. Systematic literature search in Medline for studies reporting diagnosis of subacute thyroiditis in temporal connection with vaccinations against Covid 19. Results. The literature search yielded 24 relevant references out of which 22 were "case reports" and two "Letters to the Editor" and encompassed 37 patient cases, in total. They had received a SARS-Cov2 vaccination shortly before the diagnosis (median interval to vaccination six days). In none of these cases, infection of the upper respiratory tract had previously been identified as a classic trigger of the disease. Newly occurring hyperthyroidism and increased laboratory signs of inflammation were described in 78% and 74% of cases, respectively. Atypical clinical pictures (asymptomatic, euthyroid, no inflammation marks) have been observed in both the literature and our patients suspected of thyroid cancer referred to surgery. Conclusions. In times of pandemics and the resulting vaccination, new rapidly occurring sonographic changes in the thyroid gland should be revaluated after 2-3 weeks, or recommended to undergo a fine-needle biopsy, in order to avoid unnecessary surgical interventions.


Assuntos
COVID-19 , Tireoidite Subaguda , COVID-19/prevenção & controle , Humanos , RNA Viral , SARS-CoV-2 , Tireoidite Subaguda/diagnóstico , Tireoidite Subaguda/etiologia , Tireoidite Subaguda/patologia , Vacinação/efeitos adversos
20.
Urol Int ; 106(1): 44-50, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33827096

RESUMO

BACKGROUND: To demonstrate the feasibility of resecting isolated locally relapsing seminal vesicle remnants after primary radical prostatectomy and radiotherapy. Early oncologic outcomes and prognostic risk factors for relapse are demonstrated. OBJECTIVES AND METHODS: A total of 32 patients underwent open resection of locoregional prostate cancer recurrence in seminal vesicles, as documented on either MRI, 11C-choline, or 68Ga-PSMA PET/CT scans. Age, PSA-DT, PSA, and time to recurrence after primary treatment resection status were used in a uni- and multivariate Cox regression analysis for biochemical relapse after surgery. RESULTS: Median patient age at time of salvage surgery was 70 (57-77) years. Median PSA and PSA-DT was 2.79 (0.4-61.54) ng/mL and 5.4 (1.6-20.1) months, respectively. Median surgical time and hospital stay was 132 (75-313) min and 5.5 (4-13) days, respectively. After a mean follow-up of 29 (2-92) months, 3 patients died at 8, 14, and 40 months after salvage surgery, and 6 (18.75%) patients remain without biochemical relapse and further treatment. Median progression-free survival was 12 (1-81) months. In the univariable Cox regression analysis, age at time of surgery, preoperative PSA, and the time from primary treatment to salvage surgery were identified as significant parameters for biochemical relapse. Only the interval from primary to salvage surgery was significant in the multivariate analysis with a hazard ratio of 1.008 (95% CI: 1.001-1.015, p = 0.018). In the entire cohort, 4 adjunctive surgeries (3 ureteroneocystostomies and 1 nephrectomy) were needed due to local progressive disease. CONCLUSION: Seminal vesicle resection is feasible with no significant intra- or postoperative complications. Almost all patients progressed to biochemical or systemic relapse. Salvage surgery must be seen as a preventive for local symptoms, in our experience most often postrenal ipsilateral obstruction.


Assuntos
Recidiva Local de Neoplasia/cirurgia , Prostatectomia , Neoplasias da Próstata/cirurgia , Glândulas Seminais/cirurgia , Idoso , Estudos de Viabilidade , Humanos , Masculino , Recidiva Local de Neoplasia/epidemiologia , Prostatectomia/métodos , Neoplasias da Próstata/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Terapia de Salvação , Resultado do Tratamento
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