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1.
J Chem Theory Comput ; 20(15): 6695-6705, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-38978185

RESUMO

Antibiotic resistance, particularly among Gram-negative bacteria, poses a significant healthcare challenge due to their ability to evade antibiotic action through various mechanisms. In this study, we explore the prediction of small molecule accumulation in Gram-negative bacteria by using machine learning techniques enhanced with statistical descriptors derived from molecular dynamics simulations. We begin by identifying a minimal set of molecular descriptors that maximize the model's predictive power while preserving human interpretability. We optimize model accuracy, precision, and the area under the receiver operating characteristic curve through an iterative process. We demonstrate that the inclusion of statistical descriptors significantly improves model performance across various prediction metrics. Particularly, the addition of statistical descriptors related to dipole moment and minimum projection radius enhances the model's predictive capabilities, shedding light on the physicochemical properties crucial for small molecule accumulation. Our findings highlight the importance of considering statistical moments beyond mean values in predictive modeling and suggest avenues for future research. Overall, our study provides insights into the complex dynamics of antibiotic accumulation in Escherichia coli bacterial cells, generalizable to other Gram-negative species, offering a promising approach for the discovery of effective antibacterial agents, identifying new hits, and improving them to define effective lead agents.


Assuntos
Antibacterianos , Escherichia coli , Aprendizado de Máquina , Simulação de Dinâmica Molecular , Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia
2.
Sleep Med ; 85: 191-195, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34343769

RESUMO

OBJECTIVE: To evaluate the relation between systemic iron parameters (SIP) and substantia nigra (SN) iron deposits, as assessed by transcranial sonography (TCS) in restless legs syndrome (RLS). METHODS: We conducted a cross-sectional study in RLS patients, from whom blood samples with SIP were obtained, consisting of total iron-binding capacity (TIBC), serum ferritin, hemoglobin, transferrin saturation (TSAT), serum iron, and serum transferrin. TCS was performed over the SN, and the substantia nigra echogenicity index (SNEI) was determined according to established methods. Symptom severity was evaluated using the international restless legs scale (IRLS). A Spearman correlation was performed. RESULTS: A total of 167 patients were studied. Correlations between SNEI and SIP were as follows: serum ferritin (R = 0.0422; n.s.), TSAT (R = 0.0883; n.s.), TIBC (R = -0.1091; n.s.), serum transferrin (R = -0.0420; n.s.), hemoglobin (R = 0.0185; n.s.), serum iron (R = 0.0389; n.s.). No correlation was found with age and IRLS (R = 0.1375; n.s. and R = 0.0880, n.s., respectively). CONCLUSIONS: SIP are not correlated with SN iron content in RLS, quantified by means of TCS. TCS of the SN might be a more valid estimate and could be useful in the evaluation of RLS patients.


Assuntos
Síndrome das Pernas Inquietas , Estudos Transversais , Humanos , Ferro , Síndrome das Pernas Inquietas/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana
4.
Inorg Chem ; 60(10): 7351-7363, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33913705

RESUMO

Straightforward palladium(II) catalyzed direct cross-coupling reaction between decyl, (S)-2-methyl-butyl, and dodecyl N-substituted diketopyrrolopyrrole thiophene (DPPT), including a 3-methoxy-thiophene derivative, and 6-bromo-2,2'-bipyridine afforded a series of mono- and bis-bipyridine substituted DPPT ligands 1-3. Complexation reactions with PtCl2(DMSO)2 provided ortho-metalated platinum(II) complexes 1-Pt and 2-Pt, together with the N^N^O complex 3d-Pt(N^N^O) resulted from the O-Me activation of the intermediary complex 3d-Pt(N^N). The ligand 1b and the mononuclear complexes 1a-Pt and 1b-Pt have been structurally characterized by single crystal X-ray structure, evidencing the establishment of numerous intermolecular π-π interactions in the solid state. Moreover, in the crystal structure of the model complex DMTB-Pt(N^N^O) (DMTB = 3,4-dimethoxy-(2,2'-bipyridine)) the chelating tridentate N^N^O mode is clearly evidenced. The chiral ligand 1b and its mononuclear complex 1b-Pt do not show any CD signal in solution, but they are CD active in the solid state with bisignate bands in the low energy region, opposite in sign between the ligand and the complex, suggesting helical supramolecular arrangement of the dpp chromophore in the solid state. Photophysical investigations demonstrate that all of the ligands are fluorescent with high quantum yields, while the emission is quenched for the complexes, except partially in 3d-Pt(N^N), very likely through an intersystem crossing mechanism promoted by the heavy metal. Density functional theory calculations support the differences observed between the absorption properties of the ligands, ortho- and non-ortho-metalated complexes. The highly fluorescent bipyridine ligands reported herein open the way toward multifunctional transition metal complexes and their use in organic electronics.

5.
Sleep Med ; 74: 48-55, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32841843

RESUMO

OBJECTIVE: To evaluate the incidence of iron overload and anaphylaxis following intravenous (IV) iron treatment of restless legs syndrome (RLS). METHODS: A total of 58 consecutive RLS patients, meeting clinical requirements for IV iron treatment according to current IRLSSG guidelines were recruited. IV iron treatment consisted of two 500 mg infusions of ferric carboxymaltose (FCM) administered five days apart. During each of the three follow-up visits we obtained blood samples, substantia nigra echogenity index (SNEI) by means of transcranial sonography (TCS), and assessed the severity of RLS symptoms (IRLS scale). "Iron overload risk" was defined as transferrin saturation (TSAT) > 45% on two consecutive follow-up visits. In patients who had a reduction in systemic iron levels following treatment, an additional 500 mg of FCM was administered when feasible. In such cases an additional two follow-up visits were performed. RESULTS: Among the total sample, only 2/58 participants met criteria for iron overload risk. They had no evidence of liver damage and did not require additional treatment. Among the 21 patients receiving an additional 500 mg infusion after, only one patient was diagnosed with iron overload risk. Among these three patients, only one was a hemochromatosis gene carrier. No anaphylaxis or other side-effects were reported. CONCLUSIONS: In real-life clinical conditions, the risk of iron overload is low when IV FCM is administered according to the safety limits defined in the current RLS treatment guidelines. However, a close clinical follow-up with periodic blood sampling for iron status, is needed.


Assuntos
Anafilaxia , Sobrecarga de Ferro , Síndrome das Pernas Inquietas , Anafilaxia/induzido quimicamente , Anafilaxia/tratamento farmacológico , Humanos , Ferro , Sobrecarga de Ferro/tratamento farmacológico , Síndrome das Pernas Inquietas/tratamento farmacológico , Resultado do Tratamento
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