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1.
PLoS One ; 19(3): e0298522, 2024.
Article in English | MEDLINE | ID: mdl-38478522

ABSTRACT

This study explores the capabilities of large language models to replicate the behavior of individuals with underdeveloped cognitive and language skills. Specifically, we investigate whether these models can simulate child-like language and cognitive development while solving false-belief tasks, namely, change-of-location and unexpected-content tasks. GPT-3.5-turbo and GPT-4 models by OpenAI were prompted to simulate children (N = 1296) aged one to six years. This simulation was instantiated through three types of prompts: plain zero-shot, chain-of-thoughts, and primed-by-corpus. We evaluated the correctness of responses to assess the models' capacity to mimic the cognitive skills of the simulated children. Both models displayed a pattern of increasing correctness in their responses and rising language complexity. That is in correspondence with a gradual enhancement in linguistic and cognitive abilities during child development, which is described in the vast body of research literature on child development. GPT-4 generally exhibited a closer alignment with the developmental curve observed in 'real' children. However, it displayed hyper-accuracy under certain conditions, notably in the primed-by-corpus prompt type. Task type, prompt type, and the choice of language model influenced developmental patterns, while temperature and the gender of the simulated parent and child did not consistently impact results. We conducted analyses of linguistic complexity, examining utterance length and Kolmogorov complexity. These analyses revealed a gradual increase in linguistic complexity corresponding to the age of the simulated children, regardless of other variables. These findings show that the language models are capable of downplaying their abilities to achieve a faithful simulation of prompted personas.


Subject(s)
Cognition , Language , Humans , Child Development , Linguistics , Aptitude
2.
Analyst ; 149(4): 1121-1131, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38205618

ABSTRACT

The popularity and rapid spread of new psychoactive substances is why there is an urgent need for their fast monitoring in saliva in the field with electrodes modified with a selective receptor. Oligomers of electrochemically oxidized 3-aminobenzoic acid that are deposited on the surface of a graphite screen-printed electrode (o-3ABA/G/SPE) is proposed as a selector for the analyte of forensic interest. The oligomeric structure and existence of the zwitterionic form of o-3ABA on the G/SPE surface was confirmed using scanning electron microscopy, Raman spectroscopy and cyclic voltammetry techniques. The equilibrium adsorption constants between o-3ABA and 2-aminoindane (primary amine: Kads(2-AI) = 5.31 × 104) and selected synthetic cathinones (secondary amine: Kads(butylone) = 6.12 × 105, tertiary amines: Kads(MDPV) = 3.41 × 104 and Kads(naphyrone) = 1.01 × 104) were estimated using the electrochemical impedance spectroscopy (EIS) technique. The EIS technique was applied for determining a 1.0 µM concentration of 2-AI (RSD 3.5-4.0%) and butylone (RSD 4.9-6.4%) in the model and oral fluid samples.

3.
Phys Rev E ; 102(1-1): 012125, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32795072

ABSTRACT

We consider the symmetric two-state 16-vertex model on the square lattice whose vertex weights are invariant under any permutation of adjacent edge states. The vertex-weight parameters are restricted to a critical manifold which is self-dual under the gauge transformation. The critical properties of the model are studied numerically with the Corner Transfer Matrix Renormalization Group method. Accuracy of the method is tested on two exactly solvable cases: the Ising model and a specific version of the Baxter eight-vertex model in a zero field that belong to different universality classes. Numerical results show that the two exactly solvable cases are connected by a line of critical points with the polarization as the order parameter. There are numerical indications that critical exponents vary continuously along this line in such a way that the weak universality hypothesis is violated.

4.
Acta Pharm ; 69(1): 121-128, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-31259712

ABSTRACT

The present study is designed to find out if sesquiterpenes, α-humulene (HUM), valencene (VAL), ß-caryphyllene-oxide (CAO) and trans-nerolidol (NER), are able to improve the antiproliferative effect of classical cytostatic drugs, 5-fluorouracil (FU) and oxaliplatin (1,2-diaminocyclohexaneoxalato-platinum, OxPt), in colon cancer cell lines Caco-2 and SW-620. In addition, the possible mechanisms of sesquiterpene action are studied. The results show significant ability of HUM and especially of CAO to enhance the anti-proliferative effects of FU and OxPt in cancer cell lines Caco-2 and SW-620. On the other hand, VAL and NER are ineffective. The action of CAO could be partly based on its ability to disrupt the mitochondrial membrane potential and to activate initiator caspases, but other mechanisms are probably also involved. Based on these results, CAO seems to have the potential for combination therapy of colon cancers and deserves further study.


Subject(s)
Colonic Neoplasms/drug therapy , Fluorouracil/pharmacology , Monocyclic Sesquiterpenes/pharmacology , Oxaliplatin/pharmacology , Polycyclic Sesquiterpenes/pharmacology , Sesquiterpenes/pharmacology , Caco-2 Cells , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Membrane Potential, Mitochondrial/drug effects
5.
PLoS Pathog ; 8(4): e1002580, 2012.
Article in English | MEDLINE | ID: mdl-22496638

ABSTRACT

Bordetella adenylate cyclase toxin-hemolysin (CyaA) penetrates the cytoplasmic membrane of phagocytes and employs two distinct conformers to exert its multiple activities. One conformer forms cation-selective pores that permeabilize phagocyte membrane for efflux of cytosolic potassium. The other conformer conducts extracellular calcium ions across cytoplasmic membrane of cells, relocates into lipid rafts, translocates the adenylate cyclase enzyme (AC) domain into cells and converts cytosolic ATP to cAMP. We show that the calcium-conducting activity of CyaA controls the path and kinetics of endocytic removal of toxin pores from phagocyte membrane. The enzymatically inactive but calcium-conducting CyaA-AC⁻ toxoid was endocytosed via a clathrin-dependent pathway. In contrast, a doubly mutated (E570K+E581P) toxoid, unable to conduct Ca²âº into cells, was rapidly internalized by membrane macropinocytosis, unless rescued by Ca²âº influx promoted in trans by ionomycin or intact toxoid. Moreover, a fully pore-forming CyaA-ΔAC hemolysin failed to permeabilize phagocytes, unless endocytic removal of its pores from cell membrane was decelerated through Ca²âº influx promoted by molecules locked in a Ca²âº-conducting conformation by the 3D1 antibody. Inhibition of endocytosis also enabled the native B. pertussis-produced CyaA to induce lysis of J774A.1 macrophages at concentrations starting from 100 ng/ml. Hence, by mediating calcium influx into cells, the translocating conformer of CyaA controls the removal of bystander toxin pores from phagocyte membrane. This triggers a positive feedback loop of exacerbated cell permeabilization, where the efflux of cellular potassium yields further decreased toxin pore removal from cell membrane and this further enhances cell permeabilization and potassium efflux.


Subject(s)
Adenylate Cyclase Toxin/pharmacology , Cell Membrane Permeability/drug effects , Macrophages/metabolism , Membrane Microdomains/metabolism , Potassium/metabolism , Animals , Cell Line , Clathrin/metabolism , Endocytosis/drug effects , Ion Transport/drug effects , Macrophages/cytology , Mice
6.
J Immunol ; 185(3): 1711-9, 2010 Aug 01.
Article in English | MEDLINE | ID: mdl-20610650

ABSTRACT

Inflammasome-mediated IL-1beta production is central to the innate immune defects that give rise to certain autoinflammatory diseases and may also be associated with the generation of IL-17-producing CD4(+) T (Th17) cells that mediate autoimmunity. However, the role of the inflammasome in driving adaptive immunity to infection has not been addressed. In this article, we demonstrate that inflammasome-mediated IL-1beta plays a critical role in promoting Ag-specific Th17 cells and in generating protective immunity against Bordetella pertussis infection. Using a murine respiratory challenge model, we demonstrated that the course of B. pertussis infection was significantly exacerbated in IL-1R type I-defective (IL-1RI(-/-)) mice. We found that adenylate cyclase toxin (CyaA), a key virulence factor secreted by B. pertussis, induced robust IL-1beta production by dendritic cells through activation of caspase-1 and the NALP3-containing inflammasome complex. Using mutant toxins, we demonstrate that CyaA-mediated activation of caspase-1 was not dependent on adenylate cyclase enzyme activity but was dependent on the pore-forming capacity of CyaA. In addition, CyaA promoted the induction of Ag-specific Th17 cells in wild-type but not IL-1RI(-/-) mice. Furthermore, the bacterial load was enhanced in IL-17-defective mice. Our findings demonstrate that CyaA, a virulence factor from B. pertussis, promotes innate IL-1beta production via activation of the NALP3 inflammasome and, thereby, polarizes T cell responses toward the Th17 subtype. In addition to its known role in subverting host immunity, our findings suggest that CyaA can promote IL-1beta-mediated Th17 cells, which promote clearance of the bacteria from the respiratory tract.


Subject(s)
Adenylate Cyclase Toxin/physiology , Bordetella pertussis/immunology , CD4-Positive T-Lymphocytes/immunology , Inflammation Mediators/metabolism , Interleukin-17/biosynthesis , Respiratory Tract Infections/prevention & control , Adenylate Cyclase Toxin/toxicity , Animals , CD4-Positive T-Lymphocytes/enzymology , CD4-Positive T-Lymphocytes/microbiology , Carrier Proteins/metabolism , Caspase 1/metabolism , Cell Polarity/immunology , Cells, Cultured , Epitopes, T-Lymphocyte/immunology , Inflammation/enzymology , Inflammation/microbiology , Inflammation/prevention & control , Inflammation Mediators/physiology , Interleukin-17/deficiency , Interleukin-17/physiology , Interleukin-1beta/biosynthesis , Interleukin-1beta/physiology , Intubation, Intratracheal , Mice , Mice, Inbred C57BL , Mice, Knockout , NLR Family, Pyrin Domain-Containing 3 Protein , Respiratory Tract Infections/enzymology , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/pathology
7.
Mol Microbiol ; 75(6): 1550-62, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20199594

ABSTRACT

The adenylate cyclase toxin-haemolysin of Bordetella (CyaA) targets CD11b(+) myeloid phagocytes and translocates across their cytoplasmic membrane an adenylate cyclase (AC) enzyme that catalyses conversion of cytosolic ATP into cAMP. In parallel, CyaA acts as a cytolysin forming cation-selective pores, which permeabilize cell membrane and eventually provoke cell lysis. Using cytolytic activity, potassium efflux and patch-clamp assays, we show that a combination of substitutions within the pore-forming (E570Q) and acylation-bearing domain (K860R) ablates selectively the cell-permeabilizing activity of CyaA. At the same time, however, the capacity of such mutant CyaA to translocate the AC domain across cytoplasmic membrane into cytosol of macrophage cells and to elevate cellular cAMP concentrations remained intact. Moreover, the combination of E570Q+K860R substitutions suppressed the residual cytolytic activity of the enzymatically inactive CyaA/OVA/AC(-) toxoid on CD11b-expressing monocytes, while leaving unaffected the capacity of the mutant toxoid to deliver in vitro a reporter CD8(+) T cell epitope from ovalbumin (OVA) to the cytosolic pathway of dendritic cells for MHC class I-restricted presentation and induce in vivo an OVA-specific cytotoxic T cell response. CyaA, hence, employs a mechanism of AC enzyme domain translocation across cellular membrane that avoids passage across the cytolytic pore formed by toxin oligomers.


Subject(s)
Adenylate Cyclase Toxin/metabolism , Cell Membrane/metabolism , Adenylate Cyclase Toxin/genetics , Amino Acid Substitution , Animals , Cells, Cultured , Dendritic Cells/immunology , Epitopes, T-Lymphocyte/immunology , Macrophages/immunology , Mice , Models, Biological , Monocytes/immunology , Mutagenesis, Site-Directed , Mutant Proteins/genetics , Mutant Proteins/metabolism , Ovalbumin/immunology , Protein Transport , T-Lymphocytes, Cytotoxic/immunology
8.
Pain ; 125(3): 233-243, 2006 Dec 05.
Article in English | MEDLINE | ID: mdl-16797124

ABSTRACT

Surgical procedures associated with tissue injury are often followed by increased sensitivity to innocuous and noxious stimuli in the vicinity of the surgical wound. The aim of this study was to evaluate the role of transient receptor potential vanilloid 1 receptor (TRPV1) containing nociceptors in this process, by their functional inactivation using a high-concentration intradermal injection of capsaicin in a rat plantar incision model. Paw withdrawal responses to mechanical stimuli (von Frey filaments 10-367mN) and to radiant heat applied on plantar skin were tested in animals treated with capsaicin or the vehicle 6 days and 24h before or 2h after the incision was made. In the vehicle-treated animals, mechanical and thermal sensitivity increased significantly 1-96h following the incision. Capsaicin applied 24h before the surgery was most effective and significantly diminished the development of post-incisional mechanical allodynia and hyperalgesia. Thermal hypoalgesia was present in the incised paw after the capsaicin treatment. Capsaicin application 6 days before the incision induced thermal hypoalgesia before the incision but did not prevent completely the thermal hyperalgesia after the incision, while there was also a reduction of mechanical hypersensitivity. Application of the capsaicin injection after the incision showed its first effect at 2h after the injection and at 24h the effect was comparable with the 6 days pretreatment. Our results show an important role of TRPV1-containing nociceptors in the development of post-surgical hypersensitivity and suggest that local, high-concentration capsaicin treatment could be used to reduce it.


Subject(s)
Capsaicin/administration & dosage , Nociceptors/metabolism , Pain Measurement/drug effects , Pain Threshold/drug effects , Pain, Postoperative/metabolism , Pain, Postoperative/prevention & control , TRPV Cation Channels/metabolism , Animals , Behavior, Animal/drug effects , Disease Models, Animal , Male , Nociceptors/drug effects , Rats , Rats, Wistar
9.
Anesthesiology ; 103(1): 113-25, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15983463

ABSTRACT

BACKGROUND: An incision of hairy skin of the rat's back provides a new model for postincisional pain to determine the importance of cutaneous anesthesia. METHODS: Male Sprague-Dawley rats were anesthetized with sevoflurane and given a 0.6-ml subcutaneous injection of bupivacaine (0.25%) under the incision site or the medial lumbar dorsum or at the nuchal midline, 30 min before a 1.0-cm skin incision. Mechanical stimuli (von Frey hairs, 18-250 mN) were applied to measure nociception, indicated by twitching of local subcutaneous muscles, the cutaneus trunci muscle reflex. A graded response score, averaging the twitches weighted by their vigor, or a population response score, measuring the fraction of rats that showed any response, was assessed for 3 days before and over 7 days after incision. von Frey hairs were applied 0.5 cm from the incision to test primary hyperalgesia and 2.0 cm contralateral to the incision for secondary hyperalgesia. RESULTS: Incision induced responses to stimuli that had no effect on intact skin (allodynia) and also enhanced responses to forces that normally gave less than the full reflex (hyperalgesia). Hyperalgesia was present 30 min after surgery, peaked at 3-6 h, and persisted through the week; allodynia had a similar onset but was briefer. Both changes were transiently reversed by subcutaneous morphine (2.5 mg/kg intraperitoneal). Subcutaneous bupivacaine (0.25%), injected preoperatively at the incision site and anesthetizing skin for 2-3 h, suppressed primary allodynia for 1 week but had no effect on hyperalgesia. Secondary allodynia was obliterated, and secondary hyperalgesia attenuated by this treatment. Bupivacaine injected subcutaneously at the nuchal midline before surgery was also effective in abbreviating primary and secondary allodynia, with no signs of sedation, ataxia, or preconvulsive behavior. CONCLUSIONS: Incision of rat hairy skin changes pain responses, similar to pain in humans. Preincisional subcutaneous bupivacaine selectively suppresses and shortens allodynia for times far outlasting its local anesthesia, an effect largely from systemic actions.


Subject(s)
Bupivacaine/administration & dosage , Hair Follicle/innervation , Hyperalgesia/drug therapy , Pain Measurement/drug effects , Skin/drug effects , Animals , Hyperalgesia/physiopathology , Injections, Subcutaneous , Male , Pain Measurement/methods , Pain, Postoperative/drug therapy , Pain, Postoperative/physiopathology , Rats , Rats, Sprague-Dawley , Skin/innervation , Time Factors
10.
Article in English | MEDLINE | ID: mdl-15744376

ABSTRACT

We studied p53, p63, p73 protein expression in the orofacial region of five human embryos aged 7-18 weeks of intrauterine development using a three-step immunohistochemical method. Expression of proteins in various locations was evaluated semiquantitatively. A decrease in p53, p63 and p73 proteins occurred in the 13-week-old material with the exception of the tooth germ where a drop in p73 appeared in the ninth week.


Subject(s)
DNA-Binding Proteins/analysis , Embryo, Mammalian/chemistry , Face/embryology , Mouth/embryology , Nuclear Proteins/analysis , Phosphoproteins/analysis , Trans-Activators/analysis , Tumor Suppressor Protein p53/analysis , Genes, Tumor Suppressor , Humans , Immunohistochemistry , Transcription Factors , Tumor Protein p73 , Tumor Suppressor Proteins
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