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1.
Nature ; 629(8013): 837-842, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38693262

RESUMEN

The record of past human adaptations provides crucial lessons for guiding responses to crises in the future1-3. To date, there have been no systematic global comparisons of humans' ability to absorb and recover from disturbances through time4,5. Here we synthesized resilience across a broad sample of prehistoric population time-frequency data, spanning 30,000 years of human history. Cross-sectional and longitudinal analyses of population decline show that frequent disturbances enhance a population's capacity to resist and recover from later downturns. Land-use patterns are important mediators of the strength of this positive association: farming and herding societies are more vulnerable but also more resilient overall. The results show that important trade-offs exist when adopting new or alternative land-use strategies.


Asunto(s)
Agricultura , Dinámica Poblacional , Cambio Social , Agricultura/historia , Agricultura/estadística & datos numéricos , Estudios Transversales , Historia Antigua , Estudios Longitudinales , Dinámica Poblacional/historia , Dinámica Poblacional/estadística & datos numéricos , Resiliencia Psicológica , Cambio Social/historia , Humanos
2.
EMBO J ; 40(19): e108041, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34431536

RESUMEN

The role of WNT/ß-catenin signalling in mouse neocortex development remains ambiguous. Most studies demonstrate that WNT/ß-catenin regulates progenitor self-renewal but others suggest it can also promote differentiation. Here we explore the role of WNT/STOP signalling, which stabilizes proteins during G2/M by inhibiting glycogen synthase kinase (GSK3)-mediated protein degradation. We show that mice mutant for cyclin Y and cyclin Y-like 1 (Ccny/l1), key regulators of WNT/STOP signalling, display reduced neurogenesis in the developing neocortex. Specifically, basal progenitors, which exhibit delayed cell cycle progression, were drastically decreased. Ccny/l1-deficient apical progenitors show reduced asymmetric division due to an increase in apical-basal astral microtubules. We identify the neurogenic transcription factors Sox4 and Sox11 as direct GSK3 targets that are stabilized by WNT/STOP signalling in basal progenitors during mitosis and that promote neuron generation. Our work reveals that WNT/STOP signalling drives cortical neurogenesis and identifies mitosis as a critical phase for neural progenitor fate.


Asunto(s)
Mitosis , Neocórtex/embriología , Neocórtex/metabolismo , Neurogénesis , Vía de Señalización Wnt , Secuencia de Aminoácidos , Animales , Biomarcadores , Ciclo Celular , Diferenciación Celular/genética , Ciclinas/genética , Ciclinas/metabolismo , Embrión de Mamíferos , Técnica del Anticuerpo Fluorescente , Expresión Génica , Glucógeno Sintasa Quinasa 3/metabolismo , Inmunohistoquímica , Ratones , Ratones Noqueados , Mitosis/genética , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Neurogénesis/genética , Fosforilación , Factores de Transcripción SOXC/genética , Factores de Transcripción SOXC/metabolismo
3.
J Pharmacol Exp Ther ; 390(2): 203-212, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38262744

RESUMEN

Patients with sickle cell disease (SCD) display priapism, a prolonged penile erection in the absence of sexual arousal. The current pharmacological treatments for SCD-associated priapism are limited and focused on acute interventions rather than prevention. Thus, there is an urgent need for new drug targets and preventive pharmacological therapies for this condition. This review focuses on the molecular mechanisms linked to the dysfunction of the NO-cyclic guanosine monophosphate (cGMP)-phosphodiesterase type 5 (PDE5) pathway implicated in SCD-associated priapism. In murine models of SCD, reduced nitric oxide (NO)-cGMP bioavailability in the corpus cavernosum is associated with elevated plasma hemoglobin levels, increased reactive oxygen species levels that inactive NO, and testosterone deficiency that leads to endothelial nitric oxide synthase downregulation. We discuss the consequences of the reduced cGMP-dependent PDE5 activity in response to these molecular changes, highlighting it as the primary pathophysiological mechanism leading to excessive corpus cavernosum relaxation, culminating in priapism. We also further discuss the impact of intravascular hemolysis on therapeutic approaches, present current pharmacological strategies targeting the NO-cGMP-PDE5 pathway in the penis, and identify potential pharmacological targets for future priapism therapies. In men with SCD and priapism, PDE5 inhibitor therapy and testosterone replacement have shown promising results. Recent preclinical research reported the beneficial effect of treatment with haptoglobin and NO donors. SIGNIFICANCE STATEMENT: This review discusses the molecular changes that reduce NO-cGMP bioavailability in the penis in SCD and highlights pharmacological targets and therapeutic strategies for the treatment of priapism, including PDE5 inhibitors, hormonal modulators, NO donors, hydroxyurea, soluble guanylate cyclase stimulators, haptoglobin, hemopexin, and antioxidants.


Asunto(s)
Anemia de Células Falciformes , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5 , Óxido Nítrico , Priapismo , Priapismo/etiología , Priapismo/tratamiento farmacológico , Priapismo/metabolismo , Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/metabolismo , Humanos , Óxido Nítrico/metabolismo , Masculino , Animales , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/metabolismo , GMP Cíclico/metabolismo , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Inhibidores de Fosfodiesterasa 5/farmacología
4.
Mol Phylogenet Evol ; 194: 108025, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38342160

RESUMEN

Labrundinia is a highly recognizable lineage in the Pentaneurini tribe (Diptera, Chironomidae). The distinct predatory free-swimming larvae of this genus are typically present in unpolluted aquatic environments, such as small streams, ponds, lakes, and bays. They can be found on the bottom mud, clinging to rocks and wood, and dwelling among aquatic vegetation. Labrundinia has been extensively studied in ecological research and comprises 39 species, all but one of which has been described from regions outside the Palearctic. Earlier phylogenetic studies have suggested that the initial diversification of the genus likely occurred in the Neotropical Region, with its current presence in the Nearctic Region and southern South America being the result of subsequent dispersal events. Through the integration of molecular and morphological data in a calibrated phylogeny, we reveal a complex and nuanced evolutionary history for Labrundinia, providing insights into its biogeographical and diversification patterns. In this comprehensive study, we analyze a dataset containing 46 Labrundinia species, totaling 10,662 characters, consisting of 10,616 nucleotide sites and 46 morphological characters. The molecular data was generated mainly by anchored enrichment hybrid methods. Using this comprehensive dataset, we inferred the phylogeny of the group based on a total evidence matrix. Subsequently, we employed the generated tree for time calibration and further analysis of biogeography and diversification patterns. Our findings reveal multiple dispersal events out of the Neotropics, where the group originated in the late Cretaceous approximately 72 million years ago (69-78 Ma). We further reveal that the genus experienced an early burst of diversification rates during the Paleocene, which gradually decelerated towards the present-day. We also find that the Neotropics have played a pivotal role in the evolution of Labrundinia by serving as both a cradle and a museum. By "cradle," we mean that the region has been a hotspot for the origin and diversification of new Labrundinia lineages, while "museum" refers to the region's ability to preserve ancestral lineages over extended periods. In summary, our findings indicate that the Neotropics have been a key source of genetic diversity for Labrundinia, resulting in the development of distinctive adaptations and characteristics within the genus. This evidence highlights the crucial role that these regions have played in shaping the evolutionary trajectory of Labrundinia.


Asunto(s)
Chironomidae , Animales , Filogenia , Filogeografía , América del Sur , Larva
5.
Cancer Cell Int ; 24(1): 243, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38997742

RESUMEN

Histone methyltransferases (HMTs) are enzymes that regulate histone methylation and play an important role in controlling transcription by altering the chromatin structure. Aberrant activation of HMTs has been widely reported in certain types of neoplastic cells. Among them, G9a/EHMT2 and GLP/EHMT1 are crucial for H3K9 methylation, and their dysregulation has been associated with tumor initiation and progression in different types of cancer. More recently, it has been shown that G9a and GLP appear to play a critical role in several lymphoid hematologic malignancies. Importantly, the key roles played by both enzymes in various diseases made them attractive targets for drug development. In fact, in recent years, several groups have tried to develop small molecule inhibitors targeting their epigenetic activities as potential anticancer therapeutic tools. In this review, we discuss the physiological role of GLP and G9a, their oncogenic functions in hematologic malignancies of the lymphoid lineage, and the therapeutic potential of epigenetic drugs targeting G9a/GLP for cancer treatment.

6.
Genome ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38722237

RESUMEN

Avian genomes are characterized as being more compact than other amniotes, with less diversity and density of transposable elements (TEs). In addition, birds usually show bimodal karyotypes, exhibiting a great variation in diploid numbers. Some species present unusually large sex chromosomes, possibly due to the accumulation of repetitive sequences. Avian retrotransposon-like element (AviRTE) is a long interspersed nuclear element (LINE) recently discovered in the genomes of birds and nematodes, and it is still poorly characterized in terms of chromosomal mapping and phylogenetic relationships. In this study, we mapped AviRTE isolated from the Trogon surrucura genome into the T. surrucura (TSU) karyotype. Furthermore, we analyzed the phylogenetic relationships of this LINE in birds and other vertebrates. Our results showed that the distribution pattern of AviRTE is not restricted to heterochromatic regions, with accumulation on the W chromosome of TSU, yet another species with an atypical sex chromosome and TE hybridization. The phylogenetic analysis of AviRTE sequences in birds agreed with the proposed phylogeny of species in most clades, and allowed the detection of this sequence in other species, expanding the distribution of the element.

7.
Oral Dis ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923624

RESUMEN

BACKGROUND: Oral mucositis (OM) is considered one of the most common side effects of patients undergoing cancer therapy. OM prevention plays a crucial role in the effectiveness of cancer treatment and the patient's quality of life. Different preventive treatments have been proposed in clinical trials, however with inconclusive results. MATERIALS AND METHODS: A systematic review search was conducted in PubMed, Scopus, Web of Science, and Cochrane Database to answer the PICO question: in cancer patients, do specific topical agents compared to standard treatments or placebo reduce the onset and severity of oral mucositis? The risk of bias was assessed, and a network meta-analysis was conducted. RESULTS: Of 2913 results, 30 randomized clinical trials were considered suitable for inclusion. A total of 2564 patients were analyzed, of which 1284 belonged to the test group and 1280 belonged to the control group. Natural products were the most used, followed mainly by antimicrobial agents, coating agents, and basic oral care measures. Topical sucralfate resulted in the most powerful intervention for the OM prevention (OR = 0.04, 95%C.I. = 0.01-0.25, p-value = 0.001). CONCLUSION: Due to its cytoprotective action, low cost, ease of administration, and safety, sucralfate could become a potential ally to prevent the onset of OM during cancer therapy.

8.
Cogn Emot ; 38(1): 71-89, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37847269

RESUMEN

Recently, approach-avoidance tendencies and visual perception biases have been increasingly studied using bistable point-light walkers (PLWs). Prior studies have found a facing-the-viewer bias when one is primed with general threat stimuli (e.g. angry faces), explained by the "error management theory", as failing to detect a threat as approaching is riskier than the opposite. Importantly, no study has explored how disease threat - linked to the behavioural immune system - might affect this bias. This study aimed to explore whether disease-signalling cues can alter how we perceive the motion direction of ambiguous PLWs. Throughout 3 experiments, participants indicated the motion direction of a bistable PLW previously primed with a control or disease-signalling stimuli - that is, face with a surgical mask (Experiment 1), sickness sound (Experiment 2), or face with a disease cue (Experiment 3). Results showed that sickness cues do not significantly modulate the perception of approach-avoidance behaviours. However, a pattern emerged in Experiments 2 and 3, suggesting that sickness stimuli led to more facing away percepts. Unlike other types of threat, this implies that disease-related threat stimuli might trigger a distinct perceptual bias, indicating a preference to avoid a possible infection source. Nonetheless, this finding warrants future investigations.


Asunto(s)
Percepción de Movimiento , Humanos , Percepción Visual , Movimiento (Física) , Señales (Psicología)
9.
Plant Dis ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982674

RESUMEN

A survey of Diaporthe/Phomopsis Complex (DPC) species was carried out on 479 asymptomatic soybean (Glycine max (L.) Merrill) seed samples collected from commercial soybean fields in the states of Santa Catarina (20 counties) and Rio Grande do Sul (41 counties), in the 2020/21 (n=186), 2021/22 (n=138) and 2022/23 (n=155) seasons from 120 cultivars. The seeds were provided by seed producers who collected according to the sampling standard of the Ministry of Agriculture, Livestock and Food Supply. From each sample received, 200 symptomless seeds were randomly sorted out. The seeds were surface disinfected by immersion in a sodium hypochlorite solution (1%) for two minutes and placed on Potato Dextrose Agar (PDA). The plates were incubated for 7 days at 23°C with a photoperiod of 12-h. The average prevalence of 73.7% of DPC-infected seeds. Colonies were isolated by transferring mycelial tips to PDA and incubating for 14 days at 25ºC in a 12-h photoperiod. One colony (isolate MEMR0500) had morphological characteristics similar to those reported in Lopez-Cardona (2021). This isolate had a floccose, dense colony ranging from grayish beige to brown with greenish regions and black globose pycnidia (3 to 4 pycnidia/cm²). Alpha-conidia, 5.1 to 7.0 µm x 1.5 to 2.8 µm, were observed after 30 days and were hyaline, aseptate and fusiform (Figure S1). No beta-conidia were observed. Soybean plants of cultivars BMX Cromo IPRO, BMX Zeus IPRO, BRS 5804 RR, FPS 1867 IPRO and NEO 750 IPRO were tested for pathogenicity using the toothpick inoculation method (Siviero and Menten 1995). Non-colonized toothpicks served as a negative control. Plants were incubated for four days at 25°C and 90% relative humidity. Elongated 1.0 to 2.5 cm x 0.5 to 0.9 cm lesions gray-brown/reddish-brown with a depressed center were observed in all inoculated cultivars. The fungus was reisolated and the characteristics of the colonies were identical to those previously isolated. For molecular characterization, DNA was extracted from the mycelia using the CTAB method (Doyle and Doyle 1990). End-point PCR was performed using GoTaq® Flexi DNA Polymerase (Promega, USA) and primer pairs, ITS-4F/ITS-5, T2/Bt2b and EF1-728F/EF1-986R to amplify the internal transcribed spacer (ITS) (Costamilan et al. 2008), ß-tubulin (TUB2) (Glass and Donaldson 1995), and translation elongation factor 1-α (TEF1) (Carbone and Kohn 1999) genes, respectively. The amplified fragments were sequenced and submitted to blast search (https://blast.ncbi.nlm.nih.gov/Blast.cgi) with the sequences available in GenBank. The fragment from ITS (accession number OR912979) showed 99.8% (549/582 bp) identity with Diaporthe ueckeri Udayanga & Castl. [as 'ueckerae'] [syn. D. miriciae R.G. Shivas, S.M. Thomps. & Y.P. Tan] isolate FAU656 (Ac. N. KJ590726). The sequence of TEF (Ac. N. PP372869) showed 99.7% (339/355 bp) identity with D. ueckeri FAU656 (Ac. N. KJ590747), and of TUB (Ac. N. PP372870) showed 98.9% (436/536 bp) identity with D. ueckeri FAU656 (Ac. N. KJ610881). A phylogenetic tree with amplified sequences of each gene and the corresponding representative sequences from the DPC was constructed in MEGA X (Kumar et al. 2018). The MEMR0500 isolate was clustered only with the D. ueckeri clade, confirming the identity of the fungus (Figure S2). In Brazil, this is the first report of the association of this pathogen with soybean seeds. In other countries, this pathogen has been identified as the causal agent of stem canker (Mena et al. 2020; Lopez-Cardona et al. 2021). Further research is needed to analyze the risk of this seed-associated pathogen.

10.
Genes Dev ; 30(12): 1389-94, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27313319

RESUMEN

Adrenal glands are zonated endocrine organs that are essential in controlling body homeostasis. How zonation is induced and maintained and how renewal of the adrenal cortex is ensured remain a mystery. Here we show that capsular RSPO3 signals to the underlying steroidogenic compartment to induce ß-catenin signaling and imprint glomerulosa cell fate. Deletion of RSPO3 leads to loss of SHH signaling and impaired organ growth. Importantly, Rspo3 function remains essential in adult life to ensure replenishment of lost cells and maintain the properties of the zona glomerulosa. Thus, the adrenal capsule acts as a central signaling center that ensures replacement of damaged cells and is required to maintain zonation throughout life.


Asunto(s)
Corteza Suprarrenal/fisiología , Diferenciación Celular/genética , Transducción de Señal/genética , Trombospondinas/metabolismo , Corteza Suprarrenal/citología , Animales , Proliferación Celular , Embrión de Mamíferos , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica/genética , Homeostasis/genética , Masculino , Ratones , Trombospondinas/genética , Zona Glomerular/citología , Zona Glomerular/metabolismo , beta Catenina/metabolismo
11.
Odontology ; 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38305943

RESUMEN

This study analyzed and compared the physicochemical and mechanical properties of preheated resin composite with light-cured resin cement for luting indirect restorations. 210 specimens of resin cement/resin composite were prepared according to preheating treatment heated (Htd) or not (NHtd). Light-cured resin cement (Variolink Veneer, Ivoclar), and resin composite (Microhybrid-Z100, 3 M; Nanohybrid-Empress direct, Ivoclar; and Bulk fill-Filtek One, 3 M) were used (n = 10). Resin cement specimens were not preheated. The response variables were (n = 10): film thickness, microhardness, liquid sorption and solubility. Data were analyzed by 2-way ANOVA and Tukey HSD post-test (α = 0.05). Bulk fill NHtd resin had the highest film thickness values (p < 0.001). Microhybrid and nanohybrid Htd resins had the smallest thicknesses and did not differ from the cement (p > 0.05). The highest microhardness values were found for Bulk fill NHtd and Bulk fill Htd resins. The nanohybrid and microhybrid Htd resins showed the lowest microhardness values, with no difference in cement (p > 0.05). For liquid sorption, there was no significant difference between the groups (p = 0.1941). The microhybrid Htd resin showed higher solubility values than the other materials (p = 0.0023), but it did not differ statistically from resin cement (p > 0.05). Preheating composite resins reduced the film thickness. After heating, nanohybrid and Bulk fill resins retained stable microhardness, sorption, and solubility values.

12.
Odontology ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771493

RESUMEN

One of the most promising approaches to correct periodontal bone defects and achieve periodontal regeneration is platelet-rich fibrin (PRF). This systematic review and meta-analysis aimed to evaluate the regeneration of periodontal bone defects using PRF compared to other regenerative treatments. The data search and retrieval process followed the PRISMA guidelines. An electronic search of MEDLINE, Cochrane, and PubMed databases was performed, selecting exclusively randomized clinical trials where the following were measured: probing depth reduction (PD), clinical attachment level gain (CAL), and radiographic bone fill (RBF). Out of 284 selected articles, 32 were chosen based on inclusion criteria. The use of platelet-rich fibrin (PRF) + open flap debridement (OFD), PRF + metformin, PRF + platelet-rich plasma (PRP), and PRF + OFD/bone graft (BG) significantly reduced PD and improved CAL and RBF. However, the combination of PRF + BG, PRF + metformin, and PRF + STATINS reduced CAL. The intervention of PRF combined with different treatments such as metformin, OFD, PRP, BG, and STATINS has a significant impact on improving PD and CAL. The use of PRF significantly improved the regeneration of periodontal bone defects compared to other treatments.

13.
Int J Mol Sci ; 25(1)2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38203783

RESUMEN

The O-6-methylguanine-DNA methyltransferase (MGMT) gene is a critical guardian of genomic integrity. MGMT methylation in diffuse gliomas serves as an important determinant of patients' prognostic outcomes, more specifically in glioblastomas (GBMs). In GBMs, the absence of MGMT methylation, known as MGMT promoter unmethylation, often translates into a more challenging clinical scenario, tending to present resistance to chemotherapy and a worse prognosis. A pyrosequencing (PSQ) technique was used to analyze MGMT methylation status at different cut-offs (5%, 9%, and 11%) in a sample of 78 patients diagnosed with IDH-wildtype grade 4 GBM. A retrospective analysis was provided to collect clinicopathological and prognostic data. A statistical analysis was used to establish an association between methylation status and treatment response (TR) and disease-specific survival (DSS). The patients with methylated MGMT status experienced progressive disease rates of 84.6%, 80%, and 78.4% at the respective cut-offs of 5%, 9%, and 11%. The number was considerably higher when considering unmethylated patients, as all patients (100%), regardless of the cut-off, presented progressive disease. Regarding disease-specific survival (DSS), the Hazard Ratio (HR) was HR = 0.74 (0.45-1.24; p = 0.251); HR = 0.82 (0.51-1.33; p = 0.425); and HR = 0.79 (0.49-1.29; p = 0.350), respectively. Our study concludes that there is an association between MGMT unmethylation and worse TR and DSS. The 9% cut-off demonstrated a greater potential for patient survival as a function of time, which may shed light on the future need for standardization of MGMT methylation positivity parameters in PSQ.


Asunto(s)
Glioblastoma , Guanina , Isocitrato Deshidrogenasa , Humanos , ADN , Glioblastoma/genética , Guanina/análogos & derivados , Secuenciación de Nucleótidos de Alto Rendimiento , Isocitrato Deshidrogenasa/genética , Metilación , O(6)-Metilguanina-ADN Metiltransferasa/genética , Estudios Retrospectivos
14.
Int J Mol Sci ; 25(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38892284

RESUMEN

SMYD4 is a member of the SMYD family that has lysine methyltransferase function. Little is known about the roles of SMYD4 in cancer. The aim of this study is to investigate genetic alterations in the SMYD4 gene across the most prevalent solid tumors and determine its potential as a biomarker. We performed an integrative multi-platform analysis of the most common mutations, copy number alterations (CNAs), and mRNA expression levels of the SMYD family genes using cohorts available at the Cancer Genome Atlas (TCGA), cBioPortal, and the Catalogue of Somatic Mutations in Cancer (COSMIC). SMYD genes displayed a lower frequency of mutations across the studied tumors, with none of the SMYD4 mutations detected demonstrating sufficient discriminatory power to serve as a biomarker. In terms of CNAs, SMYD4 consistently exhibited heterozygous loss and downregulation across all tumors evaluated. Moreover, SMYD4 showed low expression in tumor samples compared to normal samples, except for stomach adenocarcinoma. SMYD4 demonstrated a frequent negative correlation with other members of the SMYD family and a positive correlation between CNAs and mRNA expression. Additionally, patients with low SMYD4 expression in STAD and LUAD tumors exhibited significantly poorer overall survival. SMYD4 demonstrated its role as a tumor suppressor in the majority of tumors evaluated. The consistent downregulation of SMYD4, coupled with its association with cancer progression, underscores its potential usefulness as a biomarker.


Asunto(s)
Mutación , Neoplasias , Humanos , Neoplasias/genética , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Variaciones en el Número de Copia de ADN , N-Metiltransferasa de Histona-Lisina/genética
15.
J Cancer Educ ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38698290

RESUMEN

Angola, a country grappling with prevalent tropical diseases such as malaria, is witnessing an alarming rise in cancer-related deaths. Despite the escalating significance of cancer globally and in Angola, the nation's medical schools lack compulsory oncology disciplines in their curricula. This absence compromises the comprehensive training of medical students, preventing the development of integrated perspectives and skills crucial for addressing the growing cancer burden. This article, authored by the Angolan Oncology Research Group (AORG), proposes an oncology program for undergraduate medical students in Angola, aiming to bridge the educational gap. The program outlines discipline objectives, topics to be covered, class formats, and workload considerations.

16.
Molecules ; 29(12)2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38930825

RESUMEN

The current article reports the investigation of three new Ni(II) complexes with ONS-donor dithiocarbazate ligands: [Ni(L1)PPh3] (1), [Ni(L2)PPh3] (2), and [Ni(L2)Py] (3). Single-crystal X-ray analyses revealed mononuclear complexes with a distorted square planar geometry and the metal centers coordinated with a doubly deprotonated dithiocarbazate ligand and coligand pyridine or triphenylphosphine. The non-covalent interactions were investigated by the Hirshfeld surface and the results revealed that the strongest interactions were π⋅⋅⋅π stacking interactions and non-classical hydrogen bonds C-H···H and C-H···N. Physicochemical and spectroscopic methods indicate the same structures in the solid state and solution. The toxicity effects of the free ligands and Ni(II) complexes were tested on the human breast cancer cell line MCF-7 and non-malignant breast epithelial cell line MCF-10A. The half-maximal inhibitory concentration (IC50) values, indicating that the compounds were potent in inhibiting cell growth, were obtained for both cell lines at three distinct time points. While inhibitory effects were evident in both malignant and non-malignant cells, all three complexes demonstrated lower IC50 values for malignant breast cell lines than their non-malignant counterparts, suggesting a stronger impact on cancerous cell lines. Furthermore, molecular docking studies were performed showing the complex (2) as a promising candidate for further therapeutic exploration.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Simulación del Acoplamiento Molecular , Níquel , Humanos , Níquel/química , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Ligandos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , Línea Celular Tumoral , Cristalografía por Rayos X , Células MCF-7 , Estructura Molecular , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos
17.
J Evid Based Dent Pract ; 24(2): 101983, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38821660

RESUMEN

OBJECTIVES: The extraction of third molars is one of the most performed surgical procedures in oral and maxillofacial surgery. Pain, oedema, and trismus are the most frequently complications related in the surgical postoperative period. The literature has indicated PBM as a potential adjuvant method to reduce these complications. The aim of this review and meta-analysis is evaluate the PBM, as an optimal method to improve patient experience and minimize postoperative morbidity. Additionally, we seek to determine which wavelength, site, and frequency of application are most effective. METHODS: This review was registered in PROSPERO (CRD42023429966) and followed PRISMA guidelines. The search was carried out in the main databases, PubMed/MEDLINE, Cochrane Library, Embase, Scopus, and Lilacs, including reviews in the most important journals in the area of oral surgery and laser applied to oral surgery. In addition, all article references and also gray literature were reviewed. After the studies selection, the relevant data was collected. All the studies were randomized controlled trials and the patients were allocated into two groups: active PBM and inactive PBM. The statistical analysis was carried out using Stata v.16, and the methodological quality and risk of bias were assessed by the Jadad scale and RoB 2.0, respectively. RESULTS: Where included 22 studies and 989 subjects, to all with a minimum follow-up of 7 days. Pain and oedema showed statistically significant results in favor to the active PBM group. Especially when laser applied in infrared mode, for pain and oedema at 48 h, MD = -1.80 (CI95% -2.88, -0.72) I²â€¯= 92.13% and MD = -1.45 (CI95% -2.42, -0.48) I²â€¯= 65.01%, respectively. The same is not true for trismus at 48 h, MD = 0.07 (CI95% -0.06, 0.21) I²â€¯= 3.26%. The meta-analysis also presented results in respect of laser site of application and number of PBM sessions. CONCLUSIONS: PBM with infrared laser, in a combination intraoral and extraoral application, in one session in the immediate postoperative period, has been shown to be effective to achieve the objectives of reducing pain and oedema after third molar extraction.


Asunto(s)
Edema , Terapia por Luz de Baja Intensidad , Tercer Molar , Dolor Postoperatorio , Complicaciones Posoperatorias , Extracción Dental , Humanos , Tercer Molar/cirugía , Terapia por Luz de Baja Intensidad/métodos , Dolor Postoperatorio/prevención & control , Dolor Postoperatorio/etiología , Edema/prevención & control , Edema/etiología , Complicaciones Posoperatorias/prevención & control , Mandíbula/cirugía , Trismo/prevención & control , Trismo/etiología
18.
FASEB J ; 36(10): e22535, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36070139

RESUMEN

Patients with sickle cell disease (SCD) display priapism. Clinical studies have shown a strong positive correlation between priapism and high levels of intravascular hemolysis in men with SCD. However, there are no experimental studies that show that intravascular hemolysis promotes alterations in erectile function. Therefore, we aimed to evaluate the corpus cavernosum smooth muscle relaxant function in a murine model that displays intravascular hemolysis induced by phenylhydrazine (PHZ), as well as the role of intravascular hemolysis in increasing the stress oxidative in the penis. Corpus cavernosum strips were dissected free and placed in organ baths. Acetylcholine and electrical field stimulation (EFS)-induced corpus cavernosum relaxations in vitro were obtained. Increased corpus cavernosum relaxant responses to acetylcholine and EFS were observed in the PHZ group. Protein expression of heme oxygenase-1 increased in the corpus cavernosum of the PHZ group, but PDE5 protein expression was not modified. Preincubation with the heme oxygenase inhibitor 1 J completely reversed the increased relaxant responses to acetylcholine and EFS in PHZ mice. Protein expression of NADPH oxidase subunit gp91phox, 3-nitrotyrosine, and 4-hydroxynonenal increased in the corpus cavernosum of the PHZ group, suggesting a state of oxidative stress. Basal cGMP production was lower in the PHZ group. Our results show that intravascular hemolysis promotes increased corpus cavernosum smooth muscle relaxation associated with increased HO-1 expression, as well as increased oxidative stress associated with upregulation of gp91phox expression. Moreover, our study supports clinical studies that point to a strong positive correlation between priapism and high levels of intravascular hemolysis in men with SCD.


Asunto(s)
Anemia de Células Falciformes , Priapismo , Acetilcolina/farmacología , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/metabolismo , Animales , Hemólisis , Humanos , Masculino , Ratones , Pene , Priapismo/complicaciones
19.
PLoS Biol ; 18(11): e3000902, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33201874

RESUMEN

Coordinated development of muscles, tendons, and their attachment sites ensures emergence of functional musculoskeletal units that are adapted to diverse anatomical demands among different species. How these different tissues are patterned and functionally assembled during embryogenesis is poorly understood. Here, we investigated the morphogenesis of extraocular muscles (EOMs), an evolutionary conserved cranial muscle group that is crucial for the coordinated movement of the eyeballs and for visual acuity. By means of lineage analysis, we redefined the cellular origins of periocular connective tissues interacting with the EOMs, which do not arise exclusively from neural crest mesenchyme as previously thought. Using 3D imaging approaches, we established an integrative blueprint for the EOM functional unit. By doing so, we identified a developmental time window in which individual EOMs emerge from a unique muscle anlage and establish insertions in the sclera, which sets these muscles apart from classical muscle-to-bone type of insertions. Further, we demonstrate that the eyeballs are a source of diffusible all-trans retinoic acid (ATRA) that allow their targeting by the EOMs in a temporal and dose-dependent manner. Using genetically modified mice and inhibitor treatments, we find that endogenous local variations in the concentration of retinoids contribute to the establishment of tendon condensations and attachment sites that precede the initiation of muscle patterning. Collectively, our results highlight how global and site-specific programs are deployed for the assembly of muscle functional units with precise definition of muscle shapes and topographical wiring of their tendon attachments.


Asunto(s)
Músculos Oculomotores/embriología , Músculos Oculomotores/crecimiento & desarrollo , Tretinoina/metabolismo , Animales , Tejido Conectivo/fisiología , Desarrollo Embrionario , Ojo , Imagenología Tridimensional/métodos , Ratones/embriología , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Morfogénesis , Transducción de Señal , Tendones/fisiología , Tretinoina/fisiología
20.
Crit Rev Food Sci Nutr ; : 1-25, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37585699

RESUMEN

Plant-derived polyphenols are naturally occurring compounds widely distributed in plants. They have received greater attention in the food and pharmaceutical industries due to their potential health benefits, reducing the risk of some chronic diseases due to their antioxidant, anti-inflammatory, anticancer, cardioprotective, and neuro-action properties. Polyphenolic compounds orally administered can be used as adjuvants in several treatments but with restricted uses due to chemical instability. The review discusses the different structural compositions of polyphenols and their influence on chemical stability. Despite the potential and wide applications, there is a need to improve the delivery of polyphenolics to target the human intestine without massive chemical modifications. Oral administration of polyphenols is unfeasible due to instability, low bioaccessibility, and limited bioavailability. Nano-delivery systems based on polysaccharides (starch, pectin, chitosan, and cellulose) have been identified as a viable option for oral ingestion, potentiate biological effects, and direct-controlled delivery in specific tissues. The time and dose can be individualized for specific diseases, such as intestinal cancer. This review will address the mechanisms by which polysaccharides-based nanostructured systems can protect against degradation and enhance intestinal permeation, oral bioavailability, and the potential application of polysaccharides as nanocarriers for the controlled and targeted delivery of polyphenolic compounds.

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