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1.
Int J Mol Sci ; 25(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39000425

RESUMO

This study investigated the impact of adding hydroxyapatite nanoparticles to implant surfaces treated with zirconia blasting and acid etching (ZiHa), focusing on structural changes and bone healing parameters in low-density bone sites. The topographical characterization of titanium discs with a ZiHa surface and a commercially modified zirconia-blasted and acid-etched surface (Zi) was performed using scanning electron microscopy, profilometry, and surface-free energy. For the in vivo assessment, 22 female rats were ovariectomized and kept for 90 days, after which one implant from each group was randomly placed in each tibial metaphysis of the animals. Histological and immunohistochemical analyses were performed at 14 and 28 days postoperatively (decalcified lab processing), reverse torque testing was performed at 28 days, and histometry from calcified lab processing was performed at 60 days The group ZiHa promoted changes in surface morphology, forming evenly distributed pores. For bone healing, ZiHa showed a greater reverse torque, newly formed bone area, and bone/implant contact values compared to group Zi (p < 0.05; t-test). Qualitative histological and immunohistochemical analyses showed higher features of bone maturation for ZiHa on days 14 and 28. This preclinical study demonstrated that adding hydroxyapatite to zirconia-blasted and acid-etched surfaces enhanced peri-implant bone healing in ovariectomized rats. These findings support the potential for improving osseointegration of dental implants, especially in patients with compromised bone metabolism.


Assuntos
Durapatita , Nanopartículas , Osseointegração , Propriedades de Superfície , Zircônio , Zircônio/química , Animais , Durapatita/química , Durapatita/farmacologia , Feminino , Ratos , Nanopartículas/química , Osseointegração/efeitos dos fármacos , Implantes Dentários , Titânio/química , Tíbia/efeitos dos fármacos , Tíbia/cirurgia , Condicionamento Ácido do Dente
4.
Food Chem ; 456: 139948, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38852444

RESUMO

The natural vanilla market, which generates millions annually, is predominantly dependent on Vanilla planifolia, a species characterized by low genetic variability and susceptibility to pathogens. There is an increasing demand for natural vanilla, prized for its complex, authentic, and superior quality compared to artificial counterparts. Therefore, there is a necessity for innovative production alternatives to ensure a consistent and stable supply of vanilla flavors. In this context, vanilla crop wild relatives (WRs) emerge as promising natural sources of the spice. However, these novel species must undergo toxicity assessments to evaluate potential risks and ensure safety for consumption. This study aimed to assess the non-mutagenic and non-carcinogenic properties of ethanolic extracts from V. bahiana, V. chamissonis, V. cribbiana, and V. planifolia through integrated metabolomic profiling, in vitro toxicity assays, and in silico analyses. The integrated approach of metabolomics, in vitro assays, and in silico analyses has highlighted the need for further safety assessments of Vanilla cribbiana ethanolic extract. While the extracts of V. bahiana, V. chamissonis, and V. planifolia generally demonstrated non-mutagenic properties in the Ames assay, V. cribbiana exhibited mutagenicity at high concentrations (5000 µg/plate) in the TA98 strain without metabolic activation. This finding, coupled with the dose-dependent cytotoxicity observed in WST-1 (Water Soluble Tetrazolium) assays, a colorimetric method that assesses the viability of cells exposed to a test substance, underscores the importance of concentration in the safety evaluation of these extracts. Kaempferol and pyrogallol, identified with higher intensity in V. cribbiana, are potential candidates for in vitro mutagenicity. Although the results are not conclusive, they suggest the safety of these extracts at low concentrations. This study emphasizes the value of an integrated approach in providing a nuanced understanding of the safety profiles of natural products, advocating for cautious use and further research into V. cribbiana mutagenicity.

5.
J Oral Implantol ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38826061

RESUMO

The purpose of the present study was to evaluate the Morse effect of different internal tapered implant-abutment connections (ITCs) using a pullout test. Implants with different ITCs were selected: Short (Bicon, USA), G1; Novo Colosso (Medens, Brazil), G2; Epkut (SIN, Brazil), G3; Strong SW (SIN, Brazil), G4; Flash (Conexão, Brazil), G5 and Bone Level (Straumann, Switzerland), G6. The respective CAD files were loaded into the analysis software to measure each ITC's taper angle and implant-abutment contact area. Six implants from each group were embedded in acrylic resin blocks, and the respective universal abutments were fixed using a mallet (G1) or by applying 20 Ncm of torque (G2 to G6). After ten minutes, each abutment's retention screw was removed, and the force necessary for abutment rupture was recorded using a universal testing machine at a crosshead speed of 0.5 mm/min. The groups were compared using a one-way ANOVA and Tukey's test. Spearman's correlation was used to check the correlation of the taper angle and contacting area with the pullout strength. G1, a no-screw abutment with a 3° taper, and G2, a 10°tapered abutment tightened by 20 Ncm, presented the highest pullout strength (p<.05). The increased taper angle of G4, compared to G3, reduced the Morse effect despite their similar implant-abutment contacting areas (p<0.05). The G5 and G6 abutments loosened after screw removal and did not exhibit pullout resistance. The closer the tapered angle (r=-.958) and the higher the implant-abutment contact area (r=.880), the higher the pullout strength (p<.001). Within the limits of this study, the Morse effect is different among tapered implant-abutment connections. The closer the tapered angle and the higher the interface area, the higher the Morse effect between the abutment and the implant.

6.
Dent J (Basel) ; 12(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38920882

RESUMO

The present short-term retrospective study evaluated the implant survival rate and peri-implant bone loss around additive-manufactured titanium implants placed in sinuses grafted with Plenum Osshp (Plenum Bioengenharia, Jundia, SP, Brazil) (70HA:30ß-TCP) material. A total of 39 implants were inserted after 23 sinus floor elevation procedures in 16 consecutive patients. Prosthetic rehabilitation included fixed partial prostheses (three units), single crowns (eleven units), and fixed full arches (three units). Clinical and radiographic parameters of implant-supported restorations were evaluated after at least one year of occlusal loading. The implant-crown success criteria included the absence of pain, suppuration, and clinical mobility, an average distance between the implant shoulder and the first visible bone contact (DIB) < 1.0 mm from the initial surgery, and the absence of prosthetic complications at the implant-abutment interface. The overall cumulative implant survival rate was 97.43%. No prosthetic complications at the implant-abutment interface were reported. After one year, the mean DIB was 0.23 mm ± 0.14. Within the limits of this retrospective study, it can be concluded that 70 HA:30 ß-TCP allowed stable and reliable bone support to maintain healthy conditions around titanium dental implants produced by additive manufacturing.

8.
Int J Crit Illn Inj Sci ; 14(1): 62-65, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38715755

RESUMO

Wunderlich syndrome is characterized by the presence of abdominal pain, hematuria, and hypovolemic shock. We report a rare case of a 25-year-old pregnant woman, who came to the emergency department due to the sudden onset of low back pain and diaphoresis. The patient, during medical evaluation, experienced an altered state of consciousness. Diagnosed with hypovolemic shock, she was admitted to the operating room, where examination of the abdominal cavity revealed a left retroperitoneal hematoma. Damage control surgery was performed, but given the postoperative clinical deterioration, computerized tomography angiography of the abdomen was performed, showing a mass-like lesion arising from the upper pole of the left kidney, consistent with Wunderlich syndrome. Left nephrectomy was the definitive treatment for the 10-cm renal angiomyolipoma. Since Wunderlich syndrome is a potentially lethal entity, CT is usually the preferred diagnostic approach, and supra-selective vascular embolization is the first-line treatment.

9.
Eur Spine J ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717495

RESUMO

PURPOSE: To conduct an independent assessment of inter- and intraobserver agreement for the META score as a tool for differentiating osteoporotic vertebral fractures and multiple myeloma vertebral fractures. METHODS: This is a retrospective observational study. The magnetic resonance imaging analysis was made by two independent spinal surgeons. We designated a Subjective assessment, in which the surgeon should establish a diagnostic classification for each vertebral fracture based on personal experience: secondary to osteoporosis, categorized as a benign vertebral fracture (BVF), or attributed to multiple myeloma, categorized a malign vertebral fracture (MVF). After a 90-day interval, both surgeons repeated the evaluations. For the next step, the observers should establish a diagnosis between BVF and MVF according to the META score system, and both observers repeated the evaluations after a 90-day interval. The intra and interobserver reliability of the Subjective evaluation was studied using the kappa (κ) test. Then, the META evaluations were paralleled using the intraclass correlation coefficient (ICC). RESULTS: A total of 220 patients who had the potential to participate in the study were initially enrolled, but after applying the exclusion criteria, 44 patients were included. Thirty-three patients had BVF, and 12 patients presented MVF. Interobserver agreement for both Subjective evaluations moments (initial and 90-days interval) found a slight agreement for both moments (0.35 and 0.40 respectively). Kappa test for both META evaluations moments (initial and 90-days interval) found a moderate interobserver agreement for both moments (0.54 and 0.48 respectively). It was observed that the ICC calculated for the Initial evaluation using META score was 0.680 and that in the 90-days interval was 0.726, indicating regular to good agreement. Kappa test for intraobserver agreements for the Subjective evaluation presented moderate agreement for both Surgeons. On the other side, Kappa test for intraobserver agreements for the META evaluation presented substantial agreement for both Surgeons. The Intraclass Correlation Coefficient of the META score found presented an almost perfect agreement for both Surgeons. CONCLUSION: Intra and interobserver agreement for both surgeons were unsatisfactory. The lack of consistent reproducibility by the same observer discourages and disfavors the routine use of the META score in clinical decision making, when potentially cases of multiple myeloma may be present.

10.
Animals (Basel) ; 14(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38731383

RESUMO

This study compared the effects of butorphanol-medetomidine and butorphanol-dexmedetomidine combinations on echocardiographic parameters during propofol anaesthesia in dogs. The dogs were randomly divided into two groups. In the butorphanol-medetomidine (BM) group, butorphanol (0.2 mg/kg) and medetomidine (15 µg/kg) were intravenously administered; in the butorphanol-dexmedetomidine (BD) group, butorphanol (0.2 mg/kg) and dexmedetomidine (7.5 µg/kg) was used. Anaesthesia was induced with propofol and maintained with a constant-rate infusion of propofol (0.2 mg/kg/min). The echocardiographic parameters were assessed in conscious dogs (T0). Echocardiography was conducted again at 10 min post premedication (T1), followed by assessments at 30 (T2), 60 (T3), and 90 (T4) mins. The dogs were subjected to diagnostic procedures (radiography, computed tomography) under anaesthesia. A significant reduction in heart rate and cardiac output was noted in both groups at T1. There was no significant difference in the stroke volume between the BM and BD groups. The application of butorphanol-dexmedetomidine caused a significant increase in the left ventricular internal diameter in diastole and the diameter of the left atrium compared to that caused by butorphanol-medetomidine. This study documented that butorphanol-medetomidine and butorphanol-dexmedetomidine combinations caused similar reductions in heart rate and cardiac output in both groups. 'New´ valvular regurgitation occurred following their administration.

11.
Environ Pollut ; 355: 124219, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38797347

RESUMO

Atmospheric pollution is a major public health issue and has become increasingly critical for human health. Urban atmospheric pollution is typically assessed through physicochemical indicators aligned with environmental legislation parameters, providing data on air quality levels. While the effects of pollution on sensitive organisms serve as a warning for public health decision-makers, there remains a need to explore the interpretation of environmental data on pollutants. The use of species adapted to urban environments as sentinels enables continuous and integrated monitoring of environmental pollution implications on biological systems. In this study, we investigated the use of the plant species Tradescantia pallida as a biomonitor to evaluate the genotoxic effects of atmospheric pollution under diverse vehicular traffic conditions. T. pallida was strategically planted at the leading urban intersections in Uberlândia, Brazil. During COVID-19 pandemic lockdowns, we compared indicators such as physical, biological, and traffic data at different intersections in residential and commercial zones. The reduction in vehicular traffic highlighted the sensitivity of plant species to changes in air and soil pollutants. T. pallida showed bioaccumulation of heavy metals Cd and Cr in monitored areas with higher traffic levels. Additionally, we established a multiple linear regression model to estimate genotoxicity using the micronucleus test, with chromium concentration in the soil (X1) and particulate matter (PM) in the atmosphere (X2) identified as the primary independent variables. Our findings provide a comprehensive portrait of the impact of vehicular traffic changes on PM and offer valuable insights for refining parameters and models of Environmental Health Surveillance.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Tradescantia , Tradescantia/efeitos dos fármacos , Tradescantia/genética , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Monitoramento Biológico/métodos , Brasil , Material Particulado/análise , Material Particulado/toxicidade , Cidades , Testes para Micronúcleos , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Metais Pesados/análise , Metais Pesados/toxicidade , Humanos , COVID-19
12.
Biomimetics (Basel) ; 9(5)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38786494

RESUMO

The purpose of this study was to evaluate the repair process in rat calvaria filled with synthetic biphasic bioceramics (Plenum® Osshp-70:30, HA:ßTCP) or autogenous bone, covered with a polydioxanone membrane (PDO). A total of 48 rats were divided into two groups (n = 24): particulate autogenous bone + Plenum® Guide (AUTOPT+PG) or Plenum® Osshp + Plenum® Guide (PO+PG). A defect was created in the calvaria, filled with the grafts, and covered with a PDO membrane, and euthanasia took place at 7, 30, and 60 days. Micro-CT showed no statistical difference between the groups, but there was an increase in bone volume (56.26%), the number of trabeculae (2.76 mm), and intersection surface (26.76 mm2) and a decrease in total porosity (43.79%) in the PO+PG group, as well as higher values for the daily mineral apposition rate (7.16 µm/day). Histometric analysis presented material replacement and increased bone formation at 30 days compared to 7 days in both groups. Immunostaining showed a similar pattern between the groups, with an increase in proteins related to bone remodeling and formation. In conclusion, Plenum® Osshp + Plenum® Guide showed similar and sometimes superior results when compared to autogenous bone, making it a competent option as a bone substitute.

13.
BMC Med Educ ; 24(1): 555, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773470

RESUMO

BACKGROUND: The Progress Test is an individual assessment applied to all students at the same time and on a regular basis. The test was structured in the medical undergraduate education of a conglomerate of schools to structure a programmatic assessment integrated into teaching. This paper presents the results of four serial applications of the progress test and the feedback method to students. METHODS: This assessment comprises 120 items offered online by means of a personal password. Items are authored by faculty, peer-reviewed, and approved by a committee of experts. The items are classified by five major areas, by topics used by the National Board of Medical Examiners and by medical specialties related to a national Unified Health System. The correction uses the Item Response Theory with analysis by the "Rasch" model that considers the difficulty of the item. RESULTS: Student participation increased along the four editions of the tests, considering the number of enrollments. The median performances increased in the comparisons among the sequential years in all tests, except for test1 - the first test offered to schools. Between subsequent years of education, 2nd-1st; 4th-3rd and 5th-4th there was an increase in median scores from progress tests 2 through 4. The final year of undergraduate showed a limited increase compared to the 5th year. There is a consistent increase in the median, although with fluctuations between the observed intervals. CONCLUSION: The progress test promoted the establishment of regular feedback among students, teachers and coordinators and paved the road to engagement much needed to construct an institutional programmatic assessment.


Assuntos
Educação de Graduação em Medicina , Avaliação Educacional , Humanos , Avaliação Educacional/métodos , Estudantes de Medicina
14.
J Funct Biomater ; 15(4)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38667555

RESUMO

Plasma gel (PG) is a protein matrix prepared from platelet-poor plasma and can be utilized as a drug carrier for controlled release. We previously demonstrated its applicability as a carrier of polyphosphate. Epigallocatechin-3-gallate (EGCG) is the main flavonoid found in green tea and functions as a strong antioxidant. To explore the applicability of PG as an EGCG carrier, we examined the release of EGCG from the PG matrix using an in vitro system. Pooled platelet-poor plasma (PPP) was prepared from four healthy adult male donors, mixed with EGCG, and heated at 75 °C for 10 or 20 min to prepare the PG matrix. The PG-EGCG matrix was incubated in PBS at 37 °C, and the EGCG released into PBS was determined using spectrophotometry. The antioxidant capacity was determined based on the principle of the iodine decolorization reaction. EGCG precipitated and incorporated into the PG matrix during thermal preparation. Trypsin, used to simulate the in vivo degradation of PG, released EGCG from the PG matrix over time. The released EGCG maintained its antioxidant capacity during incubation. These results indicate that thermally prepared PG matrices can be utilized as a promising EGCG carrier in the fields of tissue engineering and regenerative medicine.

15.
Front Pediatr ; 12: 1352260, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606369

RESUMO

Background: Limited data are available on the clinical impact and economic burden of COVID-19 in the pediatric population in Argentina. We aimed to estimate the disease and economic burden of COVID-19 on children and adolescents. Methods: We analyzed official national databases and conducted a supplemental systematic review of the published literature with meta-analysis in children aged 0-18. The period of interest was from March 2020 to August 2021, before the introduction of vaccination in this age group as a national strategic plan. In addition, we used a cost of illness analysis to estimate the direct medical costs associated with COVID-19. All costs are reported in US dollars 2023. Results: A total of 450,503 confirmed COVID-19 cases and 180 multisystem inflammatory syndrome (MIS-C) were reported in Argentina in the study period. Fourteen observational clinical studies were identified. The meta-analyses of severity level from hospital patients showed that according to different studies 15%-28% of cases were asymptomatic, 68%-88% were mild or moderate, and 3%-10% were severe or critical. About 28% of children had an underlying disease. In addition, the estimated economic burden associated with COVID-19 was 80 million dollars and 4 million dollars corresponded to MISC. Conclusion: Significant impact of COVID-19 on the healthcare system and substantial economic implications for the pediatric population in Argentina were identified. The findings should help policymakers to make informed decisions and allocate resources effectively.

16.
Pathogens ; 13(4)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38668297

RESUMO

The control of infectious diseases caused by biofilms is a continuing challenge for researchers due to the complexity of their microbial structures and therapeutic implications. Photodynamic therapy as an adjunctive anti-infective treatment has been described as a possible valid approach but has not been tested in polymicrobial biofilm models. This study evaluated the effect of photodynamic therapy in vitro with methylene blue (MB) 0.01% and red LEDs (λ = 660 nm, power density ≈ 330 mW/cm2, 2 mm distance from culture) on the metabolic activity and composition of a multispecies subgingival biofilm. Test Groups LED and MB + LED showed a more significant reduction in metabolic activity than the non-LED application group (~50 and 55%, respectively). Groups LED and MB equally affected (more than 80%) the total bacterial count in biofilms. No differences were noted in the bacterial biofilm composition between the groups. In vitro LED alone or the MB + LED combination reduced the metabolic activity of bacteria in polymicrobial biofilms and the total subgingival biofilm count.

17.
Int J Mol Sci ; 25(8)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38674127

RESUMO

Platelet-rich fibrin (PRF) is a widely used autologous blood concentrate in regenerative medicine. This study aimed to characterize the cellular composition and distribution of different PRF matrices generated by high (710 g) and low (44 g) relative centrifugal forces (RCFs) and to analyze their bioactivity on human primary osteoblasts (pOBs). PRF was separated into upper layer (UL) and buffy coat (BC) fractions, and their cellular contents were assessed using histological and immunohistochemical staining. The release of platelet-derived growth factor (PDGF) and transforming growth factor (TGF-ß) was quantified using an ELISA. Indirect PRF treatment on pOBs was performed to evaluate cell viability and morphology. A histological analysis revealed higher quantities of leukocytes and platelets in the low-RCF PRF. TGF-ß release was significantly higher in the low-RCF PRF compared to the high-RCF PRF. All PRF fractions promoted pOB proliferation regardless of the centrifugation protocol used. The low-RCF PRF showed higher TGF-ß levels than the high-RCF PRF. These findings contribute to understanding the cellular mechanisms of PRF and provide insights into optimizing PRF protocols for bone regeneration, advancing regenerative medicine, and improving patient outcomes.


Assuntos
Proliferação de Células , Leucócitos , Osteoblastos , Fibrina Rica em Plaquetas , Humanos , Osteoblastos/citologia , Osteoblastos/metabolismo , Fibrina Rica em Plaquetas/metabolismo , Leucócitos/metabolismo , Leucócitos/citologia , Células Cultivadas , Fator de Crescimento Transformador beta/metabolismo , Sobrevivência Celular , Fator de Crescimento Derivado de Plaquetas/metabolismo
18.
ChemMedChem ; : e202400054, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669597

RESUMO

A series of new metal complexes, [Cu(ITZ)2Cl2] ⋅ 5H2O (1), [Cu(NO3)2(ITZ)2] ⋅ 3H2O ⋅ C4H10O (2) and [Cu(ITZ)2)(PPh3)2]NO3 ⋅ 5H2O (3) were synthesized by a reaction of itraconazole (ITZ) with the respective copper salts under reflux. The metal complexes were characterized by elemental analyses, molar conductivity, 1H and 13C{1H} nuclear magnetic resonance, UV-Vis, infrared and EPR spectroscopies. The antifungal activity of these metal complexes was evaluated against the main sporotrichosis agents: Sporothrix brasiliensis, Sporothrix schenkii, and Sporothrix globosa. All three new compounds inhibited the growth of S. brasiliensis and S. schenckii at lower concentrations than the free azole, with complex 2 able to kill all species at 4 µM and induce more pronounced alterations in fungal cells. Complexes 2 and 3 exhibited higher selectivity and no mutagenic effect at the concentration that inhibited fungal growth and affected fungal cells. The strategy of coordinating itraconazole (ITZ) to copper was successful, since the corresponding metal complexes were more effective than the parent drug. Particularly, the promising antifungal activity of the Cu-ITZ complexes makes them potential candidates for the development of an alternative drug to treat mycoses.

19.
Evid Based Dent ; 25(2): 77-78, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38589578

RESUMO

DESIGN: An umbrella review of systematic reviews and meta-analyses on dental autotransplantation (DAT). AIM: To provide a comprehensive overview of the current state of knowledge on prognostic factors, outcomes, and complications of DAT by synthesizing the evidence. METHODS: A comprehensive search of six databases was conducted for systematic reviews and meta-analyses published up to June 30, 2022. Two authors independently performed study selection, data extraction, and quality assessment using the AMSTAR 2 tool. Raw data from primary studies were analyzed using a random effects meta-analysis, and meta-regression was performed to investigate the effect of open and closed apices on the outcomes. RESULTS: Ten systematic reviews, of which nine included meta-analyses, were examined. The overall success rate of the studies was 89.4%, and the survival rate was 96.1%. The main complications were ankylosis (4.6%) and root resorption (7.4%). The analysis showed that a closed apex increased the proportion of ankylosis, resorption, and reduced survival but had no effect on success. The quality of the systematic reviews included varied, with 20% scoring moderate, 60% scoring low, and 20% scoring critically low on the AMSTAR 2 scale. CONCLUSIONS: Dental implant therapy is a reliable solution for replacing lost or damaged teeth, with high success and survival rates. However, it is a procedure that requires precision and attention to detail, along with careful selection of suitable candidates, comprehensive planning, and consideration of factors that may impact outcomes. To improve results and reduce potential complications, it is essential to establish standard clinical guidelines and conduct further extensive research.


Assuntos
Saúde Bucal , Transplante Autólogo , Humanos , Transplante Autólogo/métodos , Dente/transplante , Revisões Sistemáticas como Assunto
20.
Pharmacol Biochem Behav ; 240: 173774, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38648866

RESUMO

Memory consolidation is associated with the regulation of protein kinases, which impact synaptic functions and promote synaptogenesis. The administration of spermidine (SPD) has been shown to modulate major protein kinases associated with memory improvement, including the Ca2+-dependent protein kinase (PKC) and cAMP-dependent protein kinase (PKA), key players in the cAMP response element-binding protein (CREB) activation. Nevertheless, the initial mechanism underlying SPD-mediated memory consolidation remains unknown, as we hypothesize a potential involvement of the memory consolidation precursor, Ca2+/calmodulin-dependent protein kinase II-α (CaMKIIα), in this process. Based on this, our study aimed to investigate potential interactions among PKC, PKA, and CREB activation, mediated by CaMKIIα activation, in order to elucidate the SPD memory consolidation pathway. Our findings suggest that the post-training administration of the CaMKII inhibitor, KN-62 (0.25 nmol, intrahippocampal), prevented the memory enhancement induced by SPD (0.2 nmol, intrahippocampal) in the inhibitory avoidance task. Through western immunoblotting, we observed that phosphorylation of CaMKIIα in the hippocampus was facilitated 15 min after intrahippocampal SPD administration, resulting in the activation of PKA and CREB, 180 min after infusion, suggesting a possible sequential mechanism, since SPD with KN-62 infusion leads to a downregulation in CaMKIIα/PKA/CREB pathway. However, KN-62 does not alter the memory-facilitating effect of SPD on PKC, possibly demonstrating a parallel cascade in memory acquisition via PKA, without modulating CAMKIIα. These results suggest that memory enhancement induced by SPD administration involves crosstalk between CaMKIIα and PKA/CREB, with no PKC interaction.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico , Memória , Ratos Wistar , Transdução de Sinais , Espermidina , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ratos , Espermidina/farmacologia , Masculino , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Memória/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Fosforilação/efeitos dos fármacos , Sulfonamidas/farmacologia , Benzilaminas/farmacologia , Benzilaminas/administração & dosagem , Aprendizagem da Esquiva/efeitos dos fármacos , Proteína Quinase C/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados
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