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1.
Cell Commun Signal ; 22(1): 235, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643161

RESUMO

BACKGROUND: Antral follicles consist of an oocyte cumulus complex surrounding by somatic cells, including mural granulosa cells as the inner layer and theca cells as the outsider layer. The communications between oocytes and granulosa cells have been extensively explored in in vitro studies, however, the role of oocyte-derived factor GDF9 on in vivo antral follicle development remains elusive due to lack of an appropriate animal model. Clinically, the phenotype of GDF9 variants needs to be determined. METHODS: Whole-exome sequencing (WES) was performed on two unrelated infertile women characterized by an early rise of estradiol level and defect in follicle enlargement. Besides, WES data on 1,039 women undergoing ART treatment were collected. A Gdf9Q308X/S415T mouse model was generated based on the variant found in one of the patients. RESULTS: Two probands with bi-allelic GDF9 variants (GDF9His209GlnfsTer6/S428T, GDF9Q321X/S428T) and eight GDF9S428T heterozygotes with normal ovarian response were identified. In vitro experiments confirmed that these variants caused reduction of GDF9 secretion, and/or alleviation in BMP15 binding. Gdf9Q308X/S415T mouse model was constructed, which recapitulated the phenotypes in probands with abnormal estrogen secretion and defected follicle enlargement. Further experiments in mouse model showed an earlier expression of STAR in small antral follicles and decreased proliferative capacity in large antral follicles. In addition, RNA sequencing of granulosa cells revealed the transcriptomic profiles related to defective follicle enlargement in the Gdf9Q308X/S415T group. One of the downregulated genes, P4HA2 (a collagen related gene), was found to be stimulated by GDF9 protein, which partly explained the phenotype of defective follicle enlargement. CONCLUSIONS: GDF9 bi-allelic variants contributed to the defect in antral follicle development. Oocyte itself participated in the regulation of follicle development through GDF9 paracrine effect, highlighting the essential role of oocyte-derived factors on ovarian response.


Assuntos
Infertilidade Feminina , Camundongos , Animais , Feminino , Humanos , Infertilidade Feminina/metabolismo , Folículo Ovariano/metabolismo , Oócitos/química , Oócitos/metabolismo , Células da Granulosa/metabolismo , Estrogênios/metabolismo , Fator 9 de Diferenciação de Crescimento/genética , Fator 9 de Diferenciação de Crescimento/análise , Fator 9 de Diferenciação de Crescimento/metabolismo
2.
J Pharm Anal ; 14(4): 100898, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38634063

RESUMO

Pathogenic microorganisms produce numerous metabolites, including volatile organic compounds (VOCs). Monitoring these metabolites in biological matrices (e.g., urine, blood, or breath) can reveal the presence of specific microorganisms, enabling the early diagnosis of infections and the timely implementation of targeted therapy. However, complex matrices only contain trace levels of VOCs, and their constituent components can hinder determination of these compounds. Therefore, modern analytical techniques enabling the non-invasive identification and precise quantification of microbial VOCs are needed. In this paper, we discuss bacterial VOC analysis under in vitro conditions, in animal models and disease diagnosis in humans, including techniques for offline and online analysis in clinical settings. We also consider the advantages and limitations of novel microextraction techniques used to prepare biological samples for VOC analysis, in addition to reviewing current clinical studies on bacterial volatilomes that address inter-species interactions, the kinetics of VOC metabolism, and species- and drug-resistance specificity.

3.
ACS Sens ; 9(4): 1622-1643, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38587931

RESUMO

Genetically encoded fluorescent metal ion sensors are powerful tools for elucidating metal dynamics in living systems. Over the last 25 years since the first examples of genetically encoded fluorescent protein-based calcium indicators, this toolbox of probes has expanded to include other essential and non-essential metal ions. Collectively, these tools have illuminated fundamental aspects of metal homeostasis and trafficking that are crucial to fields ranging from neurobiology to human nutrition. Despite these advances, much of the application of metal ion sensors remains limited to mammalian cells and tissues and a limited number of essential metals. Applications beyond mammalian systems and in vivo applications in living organisms have primarily used genetically encoded calcium ion sensors. The aim of this Perspective is to provide, with the support of historical and recent literature, an updated and critical view of the design and use of fluorescent protein-based sensors for detecting essential metal ions in various organisms. We highlight the historical progress and achievements with calcium sensors and discuss more recent advances and opportunities for the detection of other essential metal ions. We also discuss outstanding challenges in the field and directions for future studies, including detecting a wider variety of metal ions, developing and implementing a broader spectral range of sensors for multiplexing experiments, and applying sensors to a wider range of single- and multi-species biological systems.


Assuntos
Proteínas Luminescentes , Metais , Humanos , Metais/química , Proteínas Luminescentes/química , Animais , Cálcio/análise , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Íons/química , Íons/análise
4.
Mol Imaging Biol ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594545

RESUMO

PURPOSE: We recently developed an optical instrument to non-invasively detect fluorescently labeled circulating tumor cells (CTCs) in mice called 'Diffuse in vivo Flow Cytometry' (DiFC). OTL38 is a folate receptor (FR) targeted near-infrared (NIR) contrast agent that is FDA approved for use in fluorescence guided surgery of ovarian and lung cancer. In this work, we investigated the use OTL38 for in vivo labeling and detection of FR + CTCs with DiFC. PROCEDURES: We tested OTL38 labeling of FR + cancer cell lines (IGROV-1 and L1210A) as well as FR- MM.1S cells in suspensions of Human Peripheral Blood Mononuclear cells (PBMCs) in vitro. We also tested OTL38 labeling and NIR-DIFC detection of FR + L1210A cells in blood circulation in nude mice in vivo. RESULTS: 62% of IGROV-1 and 83% of L1210A were labeled above non-specific background levels in suspensions of PBMCs in vitro compared to only 2% of FR- MM.1S cells. L1210A cells could be labeled with OTL38 directly in circulation in vivo and externally detected using NIR-DiFC in mice with low false positive detection rates. CONCLUSIONS: This work shows the feasibility of labeling CTCs in vivo with OTL38 and detection with DiFC. Although further refinement of the DiFC instrument and signal processing algorithms and testing with other animal models is needed, this work may eventually pave the way for human use of DiFC.

5.
ACS Sens ; 9(4): 2166-2175, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38625680

RESUMO

Relying on the strong optical absorption of hemoglobin to pulsed laser energy, photoacoustic microscopy provides morphological and functional information on microvasculature label-freely. Here, we propose speckle variance photoacoustic microscopy (SV-PAM), which harnesses intrinsic imaging contrast from temporal-varied photoacoustic signals of moving red blood cells in blood vessels, for recovering three-dimension hemodynamic images down to capillary-level resolution within the microcirculatory tissue beds in vivo. Calculating the speckle variance of consecutive photoacoustic B-scan frames acquired at the same lateral position enables accurate identification of blood perfusion and occlusion, which provides interpretations of dynamic blood flow in the microvasculature, in addition to the microvascular anatomic structures. We demonstrate high-resolution hemodynamic imaging of vascular occlusion and reperfusion in the microvasculature of mice ears in vivo. The results suggest that our SV-PAM is potentially invaluable for biomedical hemodynamic investigations, for example, imaging ischemic stroke and hemorrhagic stroke.


Assuntos
Microscopia , Técnicas Fotoacústicas , Técnicas Fotoacústicas/métodos , Animais , Camundongos , Microscopia/métodos , Hemodinâmica/fisiologia , Orelha/irrigação sanguínea , Orelha/diagnóstico por imagem , Microvasos/diagnóstico por imagem , Eritrócitos , Microcirculação
6.
Biomed Mater ; 19(3)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38626780

RESUMO

Wool derived keratin, due to its demonstrated ability to promote bone formation, has been suggested as a potential bioactive material for implant surfaces. The aim of this study was to assess the effects of keratin-coated titanium on osteoblast functionin vitroand bone healingin vivo. Keratin-coated titanium surfaces were fabricated via solvent casting and molecular grafting. The effect of these surfaces on the attachment, osteogenic gene, and osteogenic protein expression of MG-63 osteoblast-like cells were quantifiedin vitro. The effect of these keratin-modified surfaces on bone healing over three weeks using an intraosseous calvaria defect was assessed in rodents. Keratin coating did not affect MG-63 proliferation or viability, but enhanced osteopontin, osteocalcin and bone morphogenetic expressionin vitro. Histological analysis of recovered calvaria specimens showed osseous defects covered with keratin-coated titanium had a higher percentage of new bone area two weeks after implantation compared to that in defects covered with titanium alone. The keratin-coated surfaces were biocompatible and stimulated osteogenic expression in adherent MG-63 osteoblasts. Furthermore, a pilot preclinical study in rodents suggested keratin may stimulate earlier intraosseous calvaria bone healing.


Assuntos
Regeneração Óssea , Proliferação de Células , Materiais Revestidos Biocompatíveis , Queratinas , Osteoblastos , Osteogênese , Crânio , Titânio , Titânio/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/metabolismo , Regeneração Óssea/efeitos dos fármacos , Animais , Queratinas/química , Queratinas/metabolismo , Humanos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Crânio/efeitos dos fármacos , Crânio/lesões , Osteogênese/efeitos dos fármacos , Ratos , Propriedades de Superfície , Masculino , Linhagem Celular , Adesão Celular/efeitos dos fármacos , Teste de Materiais , Sobrevivência Celular/efeitos dos fármacos , Ratos Sprague-Dawley
7.
Int J Pharm ; 657: 124130, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38631484

RESUMO

The interest in Pickering emulsions is based on the possibility of replacing classical emulsifiers with solid particles. These emulsions are very attractive in the pharmaceutical field for their stability virtues and as a vehicle to deliver active ingredients. The study aimed to analyze the properties of the residual film of the Pickering emulsions on the human skin compared to conventional systems. For this project, three types of solid particles were used: titanium dioxide, zinc oxide and silicon dioxide. All of them are capable of stabilizing the oil/water interface and thus forming totally emulsified systems. To create an emulsion of reference, a classical surfactant was used as an excipient. Complementary systems containing both particles and the emulsifier were also analyzed. Then, a combined approach between physicochemical and biometrological in vivo analysis was employed. The study proved that Pickering emulsions stabilized by the metal oxides were distinct from the reference emulsion in terms of droplet sizes and organization, rheological and textural responses. Consequently, it impacted the properties of the residual film once the product was applied to the skin. The particle-stabilized emulsions formed a hydrophobic film counter to conventional excipients. Also, the Friction parameter (or the roughness of the film) was directly linked to the quantity of the particles used in the formulation and their perception on the skin surface. The use of the particles blurs the glossy effect of the oil phase. Finally, it was observed that the appearance of the residual film was impacted by the type of the particle, namely TiO2 and ZnO particles.

8.
Sleep Adv ; 5(1): zpae022, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638581

RESUMO

Sleep-wake scoring is a time-consuming, tedious but essential component of clinical and preclinical sleep research. Sleep scoring is even more laborious and challenging in rodents due to the smaller EEG amplitude differences between states and the rapid state transitions which necessitate scoring in shorter epochs. Although many automated rodent sleep scoring methods exist, they do not perform as well when scoring new datasets, especially those which involve changes in the EEG/EMG profile. Thus, manual scoring by expert scorers remains the gold standard. Here we take a different approach to this problem by using a neural network to accelerate the scoring of expert scorers. Sleep-Deep-Learner creates a bespoke deep convolution neural network model for individual electroencephalographic or local-field-potential (LFP) records via transfer learning of GoogLeNet, by learning from a small subset of manual scores of each EEG/LFP record as provided by the end-user. Sleep-Deep-Learner then automates scoring of the remainder of the EEG/LFP record. A novel REM sleep scoring correction procedure further enhanced accuracy. Sleep-Deep-Learner reliably scores EEG and LFP data and retains sleep-wake architecture in wild-type mice, in sleep induced by the hypnotic zolpidem, in a mouse model of Alzheimer's disease and in a genetic knock-down study, when compared to manual scoring. Sleep-Deep-Learner reduced manual scoring time to 1/12. Since Sleep-Deep-Learner uses transfer learning on each independent recording, it is not biased by previously scored existing datasets. Thus, we find Sleep-Deep-Learner performs well when used on signals altered by a drug, disease model, or genetic modification.

9.
Front Oncol ; 14: 1373453, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655137

RESUMO

FLASH-radiotherapy delivers a radiation beam a thousand times faster compared to conventional radiotherapy, reducing radiation damage in healthy tissues with an equivalent tumor response. Although not completely understood, this radiobiological phenomenon has been proved in several animal models with a spectrum of all kinds of particles currently used in contemporary radiotherapy, especially electrons. However, all the research teams have performed FLASH preclinical studies using industrial linear accelerator or LINAC commonly employed in conventional radiotherapy and modified for the delivery of ultra-high-dose-rate (UHDRs). Unfortunately, the delivering and measuring of UHDR beams have been proved not to be completely reliable with such devices. Concerns arise regarding the accuracy of beam monitoring and dosimetry systems. Additionally, this LINAC totally lacks an integrated and dedicated Treatment Planning System (TPS) able to evaluate the internal dose distribution in the case of in vivo experiments. Finally, these devices cannot modify dose-time parameters of the beam relevant to the flash effect, such as average dose rate; dose per pulse; and instantaneous dose rate. This aspect also precludes the exploration of the quantitative relationship with biological phenomena. The dependence on these parameters need to be further investigated. A promising advancement is represented by a new generation of electron LINAC that has successfully overcome some of these technological challenges. In this review, we aim to provide a comprehensive summary of the existing literature on in vivo experiments using electron FLASH radiotherapy and explore the promising clinical perspectives associated with this technology.

10.
Front Microbiol ; 15: 1381051, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659985

RESUMO

Finding strategies for decolonizing gut carriers of multidrug-resistant Escherichia coli (MDR-Ec) is a public-health priority. In this context, novel approaches should be validated in preclinical in vivo gut colonization models before being translated to humans. However, the use of mice presents limitations. Here, we used for the first time Zophobas morio larvae to design a new model of intestinal colonization (28-days duration, T28). Three hyperepidemic MDR-Ec producing extended-spectrum ß-lactamases (ESBLs) or carbapenemases were administered via contaminated food to larvae for the first 7 days (T7): Ec-4901.28 (ST131, CTX-M-15), Ec-042 (ST410, OXA-181) and Ec-050 (ST167, NDM-5). Growth curve analyses showed that larvae became rapidly colonized with all strains (T7, ~106-7 CFU/mL), but bacterial load remained high after the removal of contaminated food only in Ec-4901.28 and Ec-042 (T28, ~103-4 CFU/mL). Moreover, larvae receiving a force-feeding treatment with INTESTI bacteriophage cocktail (on T7 and T10 via gauge needle) were decolonized by Ec-4901.28 (INTESTI-susceptible); however, Ec-042 and Ec-050 (INTESTI-resistant) did not. Initial microbiota (before administering contaminated food) was very rich of bacterial genera (e.g., Lactococcus, Enterococcus, Spiroplasma), but patterns were heterogeneous (Shannon diversity index: range 1.1-2.7) and diverse to each other (Bray-Curtis dissimilarity index ≥30%). However, when larvae were challenged with the MDR-Ec with or without administering bacteriophages the microbiota showed a non-significant reduction of the diversity during the 28-day experiments. In conclusion, the Z. morio larvae model promises to be a feasible and high-throughput approach to study novel gut decolonization strategies for MDR-Ec reducing the number of subsequent confirmatory mammalian experiments.

11.
Heliyon ; 10(8): e29543, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38660288

RESUMO

Tadalafil (TDL) has poor bioavailability due to the less aqueous solubility and bitter taste. Oral solid dosage forms, especially tablets, have a broad market worldwide. Constraints of tablets are a long process, pollution, high processing cost, and requiring more excipient. The research was performed to optimize an eco-friendly immediate-acting pastille of TDL to put forward an alternate formulation to a tablet using advanced data mining tools. Another objective is to assess the taste masking of TDL using the Brief Access Taste Aversion (BATA) model. The amount of PEG-4000, Polyox N-10, and Kyron T-314 were chosen as critical material attributes from failure mode effect analysis. Box-Behnken design (BBD) was utilized to optimize the pastilles and ascertained the significant impact of chosen variables on disintegration time and % CDR at 10 min. The control strategy and optimal region were located using an overlay plot. The pastilles were able to release the drug within 15 min due to faster disintegration. The formulated pastilles were of uniform size, shape, and mechanical strength. The bitter taste of TDL was masked and confirmed by the BATA model. The newer formulation may be helpful in the industry due to its eco-friendly, single-step, and economical process. It unlocks a new direction in the field of oral solid dosage form as an alternative to tablets.

12.
bioRxiv ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38645166

RESUMO

Islet transplantation for treatment of diabetes is limited by availability of donor islets and requirements for immunosuppression. Stem cell-derived islets might circumvent these issues. SC-islets effectively control glucose metabolism post transplantation, but do not yet achieve full function in vitro with current published differentiation protocols. We aimed to identify markers of mature subpopulations of SC-ß cells by studying transcriptional changes associated with in vivo maturation of SC-ß cells using RNA-seq and co-expression network analysis. The ß cell-specific hormone islet amyloid polypeptide (IAPP) emerged as the top candidate to be such a marker. IAPP+ cells had more mature ß cell gene expression and higher cellular insulin content than IAPP- cells in vitro. IAPP+ INS+ cells were more stable in long-term culture than IAPP- INS+ cells and retained insulin expression after transplantation into mice. Finally, we conducted a small molecule screen to identify compounds that enhance IAPP expression. Aconitine up-regulated IAPP and could help to optimize differentiation protocols.

13.
Front Pharmacol ; 15: 1352045, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645558

RESUMO

The bioactive extracts of traditional medicinal plants are rich in polyphenols and help to rejuvenate skin. The study was designed to assess the skin rejuvenating effects of a stable cream enriched with 4% I. argentea (IaMe) extract. The quantity of polyphenols by spectrophotometric methods was TPC, 101.55 ± 0.03 mg GAE/g and total flavonoid content; 77.14 ± 0.13 mg QE/g, while HPLC-PDA revealed gallic acid; 4.91, chlorogenic acid 48.12, p-coumaric acid 0.43, and rutin 14.23 µg/g. The significant results of biological activities were observed as DPPH; 81.81% ± 0.05%, tyrosinase; 72% ± 0.23% compared to ascorbic acid (92.43% ± 0.03%), and kojic acid (78.80% ± 0.19%) respectively. Moreover, the promising sun protection effects Sun protection factor of extract (20.53) and formulation (10.59) were observed. The active cream formulation (w/o emulsion) was developed with liquid paraffin, beeswax, IaMe extract, and ABIL EM 90, which was stable for 90 days as shown by various stability parameters. The rheological results demonstrated the active formulation's non-Newtonian and pseudo-plastic characteristics and nearly spherical globules by SEM. The IaMe loaded cream was further investigated on human trial subjects for skin rejuvenating effects and visualized in 3D skin images. Herein, the results were significant compared to placebo. IaMe formulation causes a substantial drop in skin melanin from -1.70% (2 weeks) to -10.8% (12 weeks). Furthermore, it showed a significant increase in skin moisture and elasticity index from 7.7% to 39.15% and 2%-30%, respectively. According to the findings, Indigofera argentea extract has promising bioactivities and skin rejuvenating properties, rationalizing the traditional use and encouraging its exploitation for effective and economical cosmeceuticals.

14.
Theranostics ; 14(6): 2526-2543, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646640

RESUMO

Rationale: A mature tissue resident macrophage (TRM) population residing in the peritoneal cavity has been known for its unique ability to migrate to peritoneally located injured tissues and impart wound healing properties. Here, we sought to expand on this unique ability of large peritoneal macrophages (LPMs) by investigating whether these GATA6+ LPMs could also intravasate into systemic circulation and migrate to extra-peritoneally located lungs upon ablating lung-resident alveolar macrophages (AMs) by intranasally administered clodronate liposomes in mice. Methods: C12-200 cationic lipidoid-based nanoparticles were employed to selectively deliver a small interfering RNA (siRNA)-targeting CD-45 labeled with a cyanine 5.5 (Cy5.5) dye to LPMs in vivo via intraperitoneal injection. We utilized a non-invasive optical technique called Diffuse In Vivo Flow Cytometry (DiFC) to then systemically track these LPMs in real time and paired it with more conventional techniques like flow cytometry and immunocytochemistry to initially confirm uptake of C12-200 encapsulated siRNA-Cy5.5 (siRNA-Cy5.5 (C12-200)) into LPMs, and further track them from the peritoneal cavity to the lungs in a mouse model of AM depletion incited by intranasally administered clodronate liposomes. Also, we stained for LPM-specific marker zinc-finger transcription factor GATA6 in harvested cells from biofluids like broncho-alveolar lavage as well as whole blood to probe for Cy5.5-labeled LPMs in the lungs as well as in systemic circulation. Results: siRNA-Cy5.5 (C12-200) was robustly taken up by LPMs. Upon depletion of lung-resident AMs, these siRNA-Cy5.5 (C12-200) labeled LPMs rapidly migrated to the lungs via systemic circulation within 12-24 h. DiFC results showed that these LPMs intravasated from the peritoneal cavity and utilized a systemic route of migration. Moreover, immunocytochemical staining of zinc-finger transcription factor GATA6 further confirmed results from DiFC and flow cytometry, confirming the presence of siRNA-Cy5.5 (C12-200)-labeled LPMs in the peritoneum, whole blood and BALF only upon clodronate-administration. Conclusion: Our results indicate for the very first time that selective tropism, migration, and infiltration of LPMs into extra-peritoneally located lungs was dependent on clodronate-mediated AM depletion. These results further open the possibility of therapeutically utilizing LPMs as delivery vehicles to carry nanoparticle-encapsulated oligonucleotide modalities to potentially address inflammatory diseases, infectious diseases and even cancer.


Assuntos
Ácido Clodrônico , Pulmão , Macrófagos Peritoneais , Nanopartículas , Animais , Ácido Clodrônico/farmacologia , Ácido Clodrônico/administração & dosagem , Nanopartículas/química , Nanopartículas/administração & dosagem , Camundongos , Pulmão/metabolismo , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , RNA Interferente Pequeno/administração & dosagem , Fator de Transcrição GATA6/metabolismo , Lipossomos , Camundongos Endogâmicos C57BL , Carbocianinas/química , Movimento Celular/efeitos dos fármacos , Citometria de Fluxo
15.
Regul Toxicol Pharmacol ; 150: 105631, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38648873

RESUMO

Advanced therapy medicinal products (ATMPs) are among the most complex pharmaceuticals with high human specificity. Species differences severely limit the clinical relevance of in vivo data. We conducted interviews with stakeholders involved in ATMP development about their perspective on the use of in vivo studies, the perceived hurdles and associated potential solutions regarding non-clinical development of ATMPs. In total, 17 stakeholders from 9 different countries were interviewed. A workshop was held with key stakeholders to further discuss major topics identified from the interviews. Conducting in vivo studies remains the status quo for ATMPs development. The hurdles identified included determining the amount of information required before clinical entry and effective use of limited human samples to understand a treatment or for clinical monitoring. A number of key points defined the need for future in vivo studies as well as improved application and implementation of New Approach Methodology (NAM)-based approach for products within a well-known modality or technology platform. These included data transparency, understanding of the added value of in vivo studies, and continuous advancement, evaluation, and qualification of NAMs. Based on the outcome of the discussions, a roadmap with practical steps towards a human-centric safety assessment of ATMPs was established.

16.
Curr Issues Mol Biol ; 46(4): 3294-3312, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38666936

RESUMO

Heterosynaptic plasticity, along with Hebbian homosynaptic plasticity, is an important mechanism ensuring the stable operation of learning neuronal networks. However, whether heterosynaptic plasticity occurs in the whole brain in vivo, and what role(s) in brain function in vivo it could play, remains unclear. Here, we used an optogenetics approach to apply a model of intracellular tetanization, which was established and employed to study heterosynaptic plasticity in brain slices, to study the plasticity of response properties of neurons in the mouse visual cortex in vivo. We show that optogenetically evoked high-frequency bursts of action potentials (optogenetic tetanization) in the principal neurons of the visual cortex induce long-term changes in the responses to visual stimuli. Optogenetic tetanization had distinct effects on responses to different stimuli, as follows: responses to optimal and orthogonal orientations decreased, responses to null direction did not change, and responses to oblique orientations increased. As a result, direction selectivity of the neurons decreased and orientation tuning became broader. Since optogenetic tetanization was a postsynaptic protocol, applied in the absence of sensory stimulation, and, thus, without association of presynaptic activity with bursts of action potentials, the observed changes were mediated by mechanisms of heterosynaptic plasticity. We conclude that heterosynaptic plasticity can be induced in vivo and propose that it may play important homeostatic roles in operation of neural networks by helping to prevent runaway dynamics of responses to visual stimuli and to keep the tuning of neuronal responses within the range optimized for the encoding of multiple features in population activity.

17.
J Funct Biomater ; 15(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38667540

RESUMO

Dental implants and bone augmentation are among dentistry's most prevalent surgical treatments; hence, many dental implant surfaces and bone grafts have been researched to improve bone response. Such new materials were radiologically, histologically, and histomorphometrically evaluated on animals before being used on humans. As a result, several studies used animals to evaluate novel implant technologies, biocompatibility, surgical techniques, and osseointegration strategies, as preclinical research on animal models is essential to evaluate bioactive principles (on cells, compounds, and implants) that can act through multiple mechanisms and to predict animal behavior, which is difficult to predict from in vitro studies alone. In this study, we critically reviewed all research on different animal models investigating the osseointegration degree of new implant surfaces, reporting different species used in the osseointegration research over the last 30 years. Moreover, this is the first study to summarize reviews on the main animal models used in the translational research of osseointegration, including the advantages and limitations of each model and determining the ideal location for investigating osseointegration in small and large animal models. Overall, each model has advantages and disadvantages; hence, animal selection should be based on the cost of acquisition, animal care, acceptability to society, availability, tolerance to captivity, and housing convenience. Among small animal models, rabbits are an ideal model for biological observations around implants, and it is worth noting that osseointegration was discovered in the rabbit model and successfully applied to humans.

18.
J Fungi (Basel) ; 10(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38667924

RESUMO

The Candida auris species is a multidrug-resistant yeast capable of causing systemic and lethal infections. Its virulence and increase in outbreaks are a global concern, especially in hospitals where outbreaks are more recurrent. In many cases, monotherapy is not effective, and drug combinations are opted for. However, resistance to antifungals has increased over the years. In view of this, nanoemulsions (NEs) may represent a nanotechnology strategy in the development of new therapeutic alternatives. Therefore, this study developed a co-encapsulated nanoemulsion with amphotericin B (AmB) and micafungin (MICA) (NEMA) for the control of infections caused by C. auris. NEs were developed in previous studies. Briefly, the NEs were composed of a mixture of 10% sunflower oil and cholesterol as the oil phase (5:1), 10% Polyoxyethylene (20) cetyl ether (Brij® 58) and soy phosphatidylcholine as surfactant/co-surfactant (2:1), and 80% PBS as the aqueous phase. The in vivo assay used BALB/c mice weighing between 25 and 28 g that were immunosuppressed (CEUA/FCF/CAr n° 29/2021) and infected with Candida auris CDC B11903. The in vivo results show the surprising potentiate of the antifungal activity of the co-encapsulated drugs in NE, preventing yeast from causing infection in the lung and thymus. Biochemical assays showed a higher concentration of liver and kidney enzymes under treatment with AmB and MICAmB. In conclusion, this combination of drugs to combat the infection caused by C. auris can be considered an efficient therapeutic option, and nanoemulsions contribute to therapeutic potentiate, proving to be a promising new alternative.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38668841

RESUMO

Cedrol is a major bioactive compound present in the Cedrus atlantica with numerous biological properties. In this study, we elucidated the neuroprotective properties of cedrol against ischemic infarction in animal and in vitro studies. A cerebral ischemic/reperfusion model was induced in adult Wistar rats, and oxygen-glucose deprivation/reperfusion was induced in SH-SY5Y neuronal cells and treated with different concentrations of cedrol. The percentage of water content, cerebral  infarct, and neurological deficit score was assessed in experimental rats. The acetylcholinesterase activity and inflammatory cytokines were quantified to analyze the anti-inflammatory potency of cedrol. Oxidative stress marker malondialdehyde and antioxidants were quantified to evaluate the antioxidant potency of cedrol in an ischemic condition. The neuroprotective potency of cedrol was confirmed by histopathological analysis of the brain tissue of cedrol-treated I/R-induced rats. In in vitro studies, the MTT and LDH assays were performed in cedrol-treated OGD/R SH-SY5Y cells to analyze the cytoprotective effect of cedrol. The anti-inflammatory property of cedrol was confirmed by quantifying the pro-inflammatory cytokine levels in OGD/R-induced cedrol-treated SH-SY5Y cells. The results obtained prove that cedrol significantly prevents brain edema, neurological deficits, acetylcholinesterase activity, and oxidative damage in ischemic-induced rats. It inhibited neuroinflammation in ischemic-induced rats and also in in vitro models. The neuroprotective effect of cedrol during an ischemic condition was authentically established with histological analysis in an animal model and cell survival assays in an in vitro model. Overall, our results confirm that cedrol is a potent alternative drug to treat cerebral ischemia in the future.

20.
Arch Toxicol ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668861

RESUMO

2-Phenoxyethanol (PhE) is an aromatic glycol ether and is used in a variety of functions and applications, e.g., as preservative in pharmaceuticals, cosmetic and personal care products, as biocide in disinfectants (e.g. human hygiene), or as a solvent in formulations (e.g. coatings, functional fluids). Despite its widespread use, little is yet known on its biotransformation and toxicokinetics in humans. Therefore, a pilot study was conducted with oral administration of PhE (5 mg/kg body weight) to five volunteers. Blood and urine samples were collected and analyzed for PhE and three of its presumed metabolites up to 48 h post-exposure. Additionally, one volunteer was dermally exposed to PhE and monitored until 72 h post-exposure. PhE was rapidly resorbed following both oral and dermal application with tmax-levels in blood of about 1 h and 3 h, respectively. Metabolism of PhE was observed to be rather extensive with phenoxyacetic acid (PhAA) and 4-hydroxyphenoxyacetic acid (4-OH-PhAA) as the main metabolites found in blood and urine following oral and dermal exposure. PhE was excreted rapidly and efficiently via urine mostly in metabolized form: following oral exposure, on average 77% and 12% of the applied dose was excreted within 48 h as PhAA and 4-OH-PhAA, respectively. A similar metabolism pattern was observed following the single dermal exposure experiment. The obtained data on biotransformation and toxicokinetics of PhE in humans provide valuable information on this important chemical and will be highly useful for pharmacokinetic modelling and evaluation of human PhE exposure.

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