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2.
J Clin Periodontol ; 51(7): 806-817, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38708491

RESUMO

AIM: To qualitatively and quantitatively evaluate the formation and maturation of peri-implant soft tissues around 'immediate' and 'delayed' implants. MATERIALS AND METHODS: Miniaturized titanium implants were placed in either maxillary first molar (mxM1) fresh extraction sockets or healed mxM1 sites in mice. Peri-implant soft tissues were evaluated at multiple timepoints to assess the molecular mechanisms of attachment and the efficacy of the soft tissue as a barrier. A healthy junctional epithelium (JE) served as positive control. RESULTS: No differences were observed in the rate of soft-tissue integration of immediate versus delayed implants; however, overall, mucosal integration took at least twice as long as osseointegration in this model. Qualitative assessment of Vimentin expression over the time course of soft-tissue integration indicated an initially disorganized peri-implant connective tissue envelope that gradually matured with time. Quantitative analyses showed significantly less total collagen in peri-implant connective tissues compared to connective tissue around teeth around implants. Quantitative analyses also showed a gradual increase in expression of hemidesmosomal attachment proteins in the peri-implant epithelium (PIE), which was accompanied by a significant inflammatory marker reduction. CONCLUSIONS: Within the timeframe examined, quantitative analyses showed that connective tissue maturation never reached that observed around teeth. Hemidesmosomal attachment protein expression levels were also significantly reduced compared to those in an intact JE, although quantitative analyses indicated that macrophage density in the peri-implant environment was reduced over time, suggesting an improvement in PIE barrier functions. Perhaps most unexpectedly, maturation of the peri-implant soft tissues was a significantly slower process than osseointegration.


Assuntos
Implantes Dentários , Osseointegração , Animais , Camundongos , Osseointegração/fisiologia , Alvéolo Dental/cirurgia , Inserção Epitelial , Implantação Dentária Endóssea/métodos , Carga Imediata em Implante Dentário , Titânio , Tecido Conjuntivo , Vimentina/análise , Vimentina/metabolismo , Colágeno/metabolismo , Gengiva , Fatores de Tempo
4.
NPJ Parkinsons Dis ; 10(1): 15, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195756

RESUMO

Cognitive studies on Parkinson's disease (PD) reveal abnormal semantic processing. Most research, however, fails to indicate which conceptual properties are most affected and capture patients' neurocognitive profiles. Here, we asked persons with PD, healthy controls, and individuals with behavioral variant frontotemporal dementia (bvFTD, as a disease control group) to read concepts (e.g., 'sun') and list their features (e.g., hot). Responses were analyzed in terms of ten word properties (including concreteness, imageability, and semantic variability), used for group-level comparisons, subject-level classification, and brain-behavior correlations. PD (but not bvFTD) patients produced more concrete and imageable words than controls, both patterns being associated with overall cognitive status. PD and bvFTD patients showed reduced semantic variability, an anomaly which predicted semantic inhibition outcomes. Word-property patterns robustly classified PD (but not bvFTD) patients and correlated with disease-specific hypoconnectivity along the sensorimotor and salience networks. Fine-grained semantic assessments, then, can reveal distinct neurocognitive signatures of PD.

5.
Mov Disord ; 39(1): 6-16, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37921246

RESUMO

BACKGROUND: Identifying hereditary parkinsonism is valuable for diagnosis, genetic counseling, patient prioritization in trials, and studying the disease for personalized therapies. However, most studies were conducted in Europeans, and limited data exist on admixed populations like those from Latin America. OBJECTIVES: This study aims to assess the frequency and distribution of genetic parkinsonism in Latin America. METHODS: We conducted a systematic review and meta-analysis of the frequency of parkinsonian syndromes associated with genetic pathogenic variants in Latin America. We defined hereditary parkinsonism as those caused by the genes outlined by the MDS Nomenclature of Genetic Movement Disorders and heterozygous carriers of GBA1 pathogenic variants. A systematic search was conducted in PubMed, Web of Science, Embase, and LILACS in August 2022. Researchers reviewed titles and abstracts, and disagreements were resolved by a third researcher. After this screening, five researchers reanalyzed the selection criteria and extracted information based on the full paper. The frequency for each parkinsonism-related gene was determined by the presence of pathogenic/likely pathogenic variants among screened patients. Cochran's Q and I2 tests were used to quantify heterogeneity. Meta-regression, publication bias tests, and sensitivity analysis regarding study quality were also used for LRRK2-, PRKN-, and GBA1-related papers. RESULTS: We included 73 studies involving 3014 screened studies from 16 countries. Among 7668 Latin American patients, pathogenic variants were found in 19 different genes. The frequency of the pathogenic variants in LRRK2 was 1.38% (95% confidence interval [CI]: 0.52-2.57), PRKN was 1.16% (95% CI: 0.08-3.05), and GBA1 was 4.17% (95% CI: 2.57-6.08). For all meta-analysis, heterogeneity was high and publication bias tests were negative, except for PRKN, which was contradictory. Information on the number of pathogenic variants in the other genes is further presented in the text. CONCLUSIONS: This study provides insights into hereditary and GBA1-related parkinsonism in Latin America. Lower GBA1 frequencies compared to European/North American cohorts may result from limited access to gene sequencing. Further research is vital for regional prevalence understanding, enabling personalized care and therapies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Transtornos Parkinsonianos , Humanos , América Latina/epidemiologia , Transtornos Parkinsonianos/epidemiologia , Transtornos Parkinsonianos/genética
6.
Mov Disord ; 38(9): 1625-1635, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37469269

RESUMO

BACKGROUND: Sex differences in Parkinson's disease (PD) risk are well-known. However, the role of sex chromosomes in the development and progression of PD is still unclear. OBJECTIVE: The objective of this study was to perform the first X-chromosome-wide association study for PD risk in a Latin American cohort. METHODS: We used data from three admixed cohorts: (1) Latin American Research consortium on the Genetics of Parkinson's Disease (n = 1504) as discover cohort, and (2) Latino cohort from International Parkinson Disease Genomics Consortium (n = 155) and (3) Bambui Aging cohort (n = 1442) as replication cohorts. We also developed an X-chromosome framework specifically designed for admixed populations. RESULTS: We identified eight linkage disequilibrium regions associated with PD. We replicated one of these regions (top variant rs525496; discovery odds ratio [95% confidence interval]: 0.60 [0.478-0.77], P = 3.13 × 10-5 replication odds ratio: 0.60 [0.37-0.98], P = 0.04). rs5525496 is associated with multiple expression quantitative trait loci in brain and non-brain tissues, including RAB9B, H2BFM, TSMB15B, and GLRA4, but colocalization analysis suggests that rs5525496 may not mediate risk by expression of these genes. We also replicated a previous X-chromosome-wide association study finding (rs28602900), showing that this variant is associated with PD in non-European populations. CONCLUSIONS: Our results reinforce the importance of including X-chromosome and diverse populations in genetic studies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Cromossomos Humanos X , Doença de Parkinson , Feminino , Humanos , Masculino , Estudo de Associação Genômica Ampla , Hispânico ou Latino , América Latina , Doença de Parkinson/genética , Fatores Sexuais , Cromossomos Humanos X/genética , Desequilíbrio de Ligação/genética
7.
Life (Basel) ; 13(7)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37511809

RESUMO

The present work studies the influence of pH on the stability of thiosulfinates, compounds responsible for the bacteriostatic properties shown by ethanolic and acetonic garlic extracts (EGE and AGE) against the in vitro growth of Helicobacter pylori (Hp), a bacterium which is implicated in the etiology of diverse gastrointestinal diseases. The influence of pH and time on the stability of thiosulfinates and the microbiological activities of EGE and AGE has been evaluated at human body temperature (37 °C) and in a pH range of 0.9-4.7. A marked decrease in thiosulfinate concentration was observed in a relatively short time at pH values below 2.0. However, at pH values over 2.0, the samples maintained 70% of thiosulfinate concentration for 12 h. The inhibition halo diameters showed a maximum value at pH 2.50, with an inhibition halo of 28.94 ± 0.61 mm. The reduction in the activity at pH values below 2.0 was particularly remarkable. These results suggest that, for medical application, the pH of the selected extracts must only be maintained above 2 to maintain a high level of antibacterial activity. This fact would overcome the need for proton pump inhibitors and/or antibiotics during the treatment of Hp infections in human patients.

8.
iScience ; 26(7): 107085, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37361875

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) Omicron variant sub-lineages spread rapidly worldwide, mostly due to their immune-evasive properties. This has put a significant part of the population at risk for severe disease and underscores the need for effective anti-SARS-CoV-2 agents against emergent strains in vulnerable patients. Camelid nanobodies are attractive therapeutic candidates due to their high stability, ease of large-scale production, and potential for delivery via inhalation. Here, we characterize the receptor binding domain (RBD)-specific nanobody W25 and show superior neutralization activity toward Omicron sub-lineages in comparison to all other SARS-CoV2 variants. Structure analysis of W25 in complex with the SARS-CoV2 spike glycoprotein shows that W25 engages an RBD epitope not covered by any of the antibodies previously approved for emergency use. In vivo evaluation of W25 prophylactic and therapeutic treatments across multiple SARS-CoV-2 variant infection models, together with W25 biodistribution analysis in mice, demonstrates favorable pre-clinical properties. Together, these data endorse W25 for further clinical development.

10.
Front Robot AI ; 10: 1127496, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37064576

RESUMO

Space resource utilisation is opening a new space era. The scientific proof of the presence of water ice on the south pole of the Moon, the recent advances in oxygen extraction from lunar regolith, and its use as a material to build shelters are positioning the Moon, again, at the centre of important space programs. These worldwide programs, led by ARTEMIS, expect robotics to be the disrupting technology enabling humankind's next giant leap. However, Moon robots require a high level of autonomy to perform lunar exploration tasks more efficiently without being constantly controlled from Earth. Furthermore, having more than one robotic system will increase the resilience and robustness of the global system, improving its success rate, as well as providing additional redundancy. This paper introduces the Resilient Exploration and Lunar Mapping System, developed with a scalable architecture for semi-autonomous lunar mapping. It leverages Visual Simultaneous Localization and Mapping techniques on multiple rovers to map large lunar environments. Several resilience mechanisms are implemented, such as two-agent redundancy, delay invariant communications, a multi-master architecture different control modes. This study presents the experimental results of REALMS with two robots and its potential to be scaled to a larger number of robots, increasing the map coverage and system redundancy. The system's performance is verified and validated in a lunar analogue facility, and a larger lunar environment during the European Space Agency (ESA)-European Space Resources Innovation Centre Space Resources Challenge. The results of the different experiments show the efficiency of REALMS and the benefits of using semi-autonomous systems.

11.
Neuroepidemiology ; 57(3): 176-184, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37121230

RESUMO

INTRODUCTION: Huntington's disease (HD) is a neurodegenerative, autosomal dominant disabling condition due to an expansion of the CAG trinucleotide in the HTT gene. Motor, psychiatric, and cognitive disorders characterize it. Chilean reports on HD in the era of molecular diagnosis were wanted. METHODS: This is a retrospective analysis of a prospective cohort of patients with HD seen at the Center for Movement Disorders (CETRAM) in Chile between 2013 and 2019. Sociodemographic, genotype, and neuropsychiatric features were investigated. RESULTS: One hundred three probands with HD were identified. The majority (63.1%) were born in the metropolitan region, followed by the VIII and V regions with 8.73% and 7.76%, respectively. When pedigrees were analyzed, ninety unrelated families encompassing 1,007 individuals were identified; among relatives, other 35 manifested HD, and 106 died of HD. Besides, five hundred seventy-nine individuals were at genetic risk. The minimum estimated prevalence of HD in Chile in 2019 was 0.72 × 100,000 inhabitants. The mean CAG repeats (CAGR) of 47.2 ± 10.74 for the expanded allele and 17.93 ± 2.05 for the normal allele. The mean age of onset was 41.39 ± 13.47 years. Juvenile cases represented 7.8% of this cohort, and 4.9% had a late onset. There was a negative correlation between the age of onset and the CAGR of the expanded allele (r =-0.84 p < 0.0001). Besides, 79.6% had a family history of HD. CONCLUSIONS: This is the first report characterizing genetics, motor, and neuropsychiatric features in patients with HD in Chile. The mean length of CAGR expansion of the abnormal allele was similar to previous reports in North America (i.e., Mexico and Canada) and higher than that reported in the neighboring country of Argentina. According to previous estimations, the minimal prevalence of HD in Chile may be lower than expected.


Assuntos
Doença de Huntington , Humanos , Adulto , Pessoa de Meia-Idade , Doença de Huntington/epidemiologia , Doença de Huntington/genética , Chile/epidemiologia , Estudos Retrospectivos , Repetições de Trinucleotídeos , Estudos Prospectivos
12.
medRxiv ; 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36778409

RESUMO

Sex differences in Parkinson Disease (PD) risk are well-known. However, it is still unclear the role of sex chromosomes in the development and progression of PD. We performed the first X-chromosome Wide Association Study (XWAS) for PD risk in Latin American individuals. We used data from three admixed cohorts: (i) Latin American Research consortium on the GEnetics of Parkinson's Disease (n=1,504) as discover cohort and (ii) Latino cohort from International Parkinson Disease Genomics Consortium (n = 155) and (iii) Bambui Aging cohort (n= 1,442) as replication cohorts. After developing a X-chromosome framework specifically designed for admixed populations, we identified eight linkage disequilibrium regions associated with PD. We fully replicated one of these regions (top variant rs525496; discovery OR [95%CI]: 0.60 [0.478 - 0.77], p = 3.13 × 10 -5 ; replication OR: 0.60 [0.37-0.98], p = 0.04). rs525496 is an expression quantitative trait loci for several genes expressed in brain tissues, including RAB9B, H2BFM, TSMB15B and GLRA4 . We also replicated a previous XWAS finding (rs28602900), showing that this variant is associated with PD in non-European populations. Our results reinforce the importance of including X-chromosome and diverse populations in genetic studies.

13.
Curr Osteoporos Rep ; 21(2): 228-240, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36807035

RESUMO

PURPOSE OF REVIEW: There is a growing appreciation within the scientific community that cells exhibit regional variation. Whether the variation is attributable to differences in embryonic origin or anatomical location and mechanical loading has not been elucidated; what is clear, however, is that adult cells carry positional information that ultimately affects their functions. The purpose of this review is to highlight the functions of osteocytes in the craniomaxillofacial (CMF) skeleton as opposed to elsewhere in the body, and in doing so gain mechanistic insights into genetic conditions and chemically-induced diseases that particularly affect this region of our anatomy. RECENT FINDINGS: In the CMF skeleton, elevated Wnt/ß-catenin signaling affects not only bone mass and volume, but also mineralization of the canalicular network and osteocyte lacunae. Aberrant elevation in the Wnt/ß-catenin pathway can also produce micropetrosis and osteonecrosis of CMF bone, presumably due to a disruption in the signaling network that connects osteocytes to one another, and to osteoblasts on the bone surface.


Assuntos
Osteócitos , Via de Sinalização Wnt , beta Catenina , Humanos , beta Catenina/metabolismo , Osso e Ossos/metabolismo , Osteoblastos/metabolismo , Osteócitos/metabolismo
16.
Parkinsonism Relat Disord ; 102: 7-15, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35917738

RESUMO

BACKGROUND: Large-scale Parkinson's disease (PD) genome-wide association studies (GWAS) have, until recently, only been conducted on subjects with European-ancestry. Consequently, polygenic risk scores (PRS) constructed using PD GWAS data are likely to be less predictive when applied to non-European cohorts. METHODS: Using GWAS data from the largest study to date, we constructed a PD PRS for a Latino PD cohort (1497 subjects from LARGE-PD) and tested it for association with PD status and age at onset. We validated the PRS performance by testing it in an independent Latino cohort (448 subjects) and by repeating the analysis in LARGE-PD with the addition of 440 external Peruvian controls. We also tested SNCA haplotypes for association with PD risk in LARGE-PD and a European-ancestry PD cohort. RESULTS: The GWAS-significant PD PRS had an area under the receiver-operator curve (AUC) of 0.668 (95% CI: 0.640-0.695) in LARGE-PD. The inclusion of external Peruvian controls mitigated this result, dropping the AUC 0.632 (95% CI: 0.607-0.657). At the SNCA locus, haplotypes differ by ancestry. Ancestry-specific SNCA haplotypes were associated with PD status in both LARGE-PD and the European-ancestry cohort (p-value < 0.05). These haplotypes both include the rs356182 G-allele, but only share 14% of their variants overall. CONCLUSION: The PD PRS has potential for PD risk prediction in Latinos, but variability caused by admixture patterns and bias in a European-ancestry PD PRS data limits its utility. The inclusion of diverse subjects can help elucidate PD risk loci and improve risk prediction in non-European cohorts.


Assuntos
Estudo de Associação Genômica Ampla , Doença de Parkinson , Predisposição Genética para Doença/genética , Haplótipos , Hispânico ou Latino/genética , Humanos , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , alfa-Sinucleína/genética
17.
Biochim Biophys Acta Mol Basis Dis ; 1868(9): 166449, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35618183

RESUMO

There is an inverse relationship between the differentiation of mesenchymal stem cells (MSCs) along either an adipocyte or osteoblast lineage, with lineage differentiation known to be mediated by transcription factors PPARγ and Runx2, respectively. Endogenous ligands for PPARγ are generated during the hydrolysis of triacylglycerols to fatty acids through the actions of lipases such as hormone sensitive lipase (HSL). To examine whether reduced production of endogenous PPARγ ligands would influence bone regeneration, we examined the effects of HSL knockout on fracture repair in mice using a tibial mono-cortical defect as a model. We found an improved rate of fracture repair in HSL-ko mice documented by serial µCT and bone histomorphometry compared to wild-type (WT) mice. Similarly, accelerated rates of bone regeneration were observed with a calvarial model where implantation of bone grafts from HSL-ko mice accelerated bone regeneration at the injury site. Further analysis revealed improved MSC differentiation down osteoblast and chondrocyte lineage with inhibition of HSL. MSC recruitment to the injury site was greater in HSL-ko mice than WT. Finally, we used single cell RNAseq to understand the osteoimmunological differences between WT and HSL-ko mice and found changes in the pre-osteoclast population. Our study shows HSL-ko mice as an interesting model to study improvements to bone injury repair. Furthermore, our study highlights the potential importance of pre-osteoclasts and osteoclasts in bone repair.


Assuntos
PPAR gama , Esterol Esterase , Animais , Regeneração Óssea/genética , Ligantes , Camundongos , Camundongos Knockout , Esterol Esterase/genética
19.
Rev. méd. Chile ; 149(12): 1699-1706, dic. 2021. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-1389419

RESUMO

BACKGROUND: The progression of Parkinson's disease is associated with complications, most of them preventable. AIM: To analyze hospitalizations with a diagnosis of Parkinson's disease in Chile, comparing the different health subsystems. MATERIAL AND METHODS: Analysis of hospital discharge database available at the website of the Chilean Ministry of Health. Discharges that incorporated the diagnosis of Parkinson's disease (ICD 10 code G20), between the years 2001 and 2018 were analyzed. RESULTS: The rate of discharges with the diagnosis of Parkinson's disease was 34.5 per 100,000 hospitalizations. The figures were 55.2 and 29.8 discharges per 100,000 in 2001 and 2018, respectively. Sixty seven percent of hospital admissions for Parkinson's occurred in the public sector and corresponded to beneficiaries of the public health insurance system (FONASA). Beneficiaries of private insurance systems accounted for 12% of hospital admissions. The mean hospital stay was 13.4 days. CONCLUSIONS: There is a decrease over time in the rate of hospitalizations with Parkinson's disease. This trend may be related with the incorporation of this disease in a special governmental program that guarantees a timely access to diagnosis and treatment.


Assuntos
Humanos , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia , Doença de Parkinson/epidemiologia , Chile/epidemiologia , Hospitalização , Hospitais , Tempo de Internação
20.
Front Genet ; 12: 671079, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630506

RESUMO

In adulthood, the ability to digest lactose, the main sugar present in milk of mammals, is a phenotype (lactase persistence) observed in historically herder populations, mainly Northern Europeans, Eastern Africans, and Middle Eastern nomads. As the -13910∗T allele in the MCM6 gene is the most well-characterized allele responsible for the lactase persistence phenotype, the -13910C > T (rs4988235) polymorphism is commonly evaluated in lactase persistence studies. Lactase non-persistent adults may develop symptoms of lactose intolerance when consuming dairy products. In the Americas, there is no evidence of the consumption of these products until the arrival of Europeans. However, several American countries' dietary guidelines recommend consuming dairy for adequate human nutrition and health promotion. Considering the extensive use of dairy and the complex ancestry of Pan-American admixed populations, we studied the distribution of -13910C > T lactase persistence genotypes and its flanking haplotypes of European origin in 7,428 individuals from several Pan-American admixed populations. We found that the -13910∗T allele frequency in Pan-American admixed populations is directly correlated with allele frequency of the European sources. Moreover, we did not observe any overrepresentation of European haplotypes in the -13910C > T flanking region, suggesting no selective pressure after admixture in the Americas. Finally, considering the dominant effect of the -13910∗T allele, our results indicate that Pan-American admixed populations are likely to have higher frequency of lactose intolerance, suggesting that general dietary guidelines deserve further evaluation across the continent.

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