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1.
Clin Transplant ; 38(7): e15379, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38952196

ABSTRACT

BACKGROUND: Introducing new liver transplantation (LT) practices, like unconventional donor use, incurs higher costs, making evaluation of their prognostic justification crucial. This study reexamines the spread pattern of new LT practices and its prognosis across the United States. METHODS: The study investigated the spread pattern of new practices using the UNOS database (2014-2023). Practices included LT for hepatitis B/C (HBV/HCV) nonviremic recipients with viremic donors, LT for COVID-19-positive recipients, and LT using onsite machine perfusion (OMP). One year post-LT patient and graft survival were also evaluated. RESULTS: LTs using HBV/HCV donors were common in the East, while LTs for COVID-19 recipients and those using OMP started predominantly in California, Arizona, Texas, and the Northeast. K-means cluster analysis identified three adoption groups: facilities with rapid, slow, and minimal adoption rates. Rapid adoption occurred mainly in high-volume centers, followed by a gradual increase in middle-volume centers, with little increase in low-volume centers. The current spread patterns did not significantly affect patient survival. Specifically, for LTs with HCV donors or COVID-19 recipients, patient and graft survivals in the rapid-increasing group was comparable to others. In LTs involving OMP, the rapid- or slow-increasing groups tended to have better patient survival (p = 0.05) and significantly improved graft survival rates (p = 0.02). Facilities adopting new practices often overlap across different practices. DISCUSSION: Our analysis revealed three distinct adoption groups across all practices, correlating the adoption aggressiveness with LT volume in centers. Aggressive adoption of new practices did not compromise patient and graft survivals, supporting the current strategy. Understanding historical trends could predict the rise in future LT cases with new practices, aiding in resource distribution.


Subject(s)
COVID-19 , Graft Survival , Liver Transplantation , SARS-CoV-2 , Humans , Liver Transplantation/statistics & numerical data , United States/epidemiology , COVID-19/epidemiology , Female , Male , Middle Aged , Tissue and Organ Procurement/statistics & numerical data , Tissue Donors/supply & distribution , Tissue Donors/statistics & numerical data , Adult , Survival Rate , Prognosis , Practice Patterns, Physicians'/statistics & numerical data
2.
Physiol Genomics ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38975795

ABSTRACT

Gaining insight into the diversity, structure, and metabolic functions of microbial communities is essential for understanding their roles in host health and ecosystem dynamics. However, research on the seahorse-associated microbiome remains limited, despite these threatened fish facing increasing human pressures worldwide. Here, we explored the microbial diversity and metabolic functions of the skin and gut of the tiger tail seahorse (Hippocampus comes) and its surrounding environment using shotgun metagenomics and bioinformatics. Members of the Pseudomonadota phylum were dominant in the skin microbiome, whereas Bacteroidota was dominant in the gut. Bacillota, Actinomycetota, and Planctomycetota were also detected in the seahorse-associated microbiome. Statistical analysis revealed significant differences (p<0.01) in species diversity between skin and gut microbiomes, with members belonging to the Moraxellaceae family being dominant on the skin and the Bacteroidaceae family in the gut. Moreover, the surrounding environment (water or sediment) did not have a direct effect on the seahorse microbiome composition. The skin microbiome exhibited a higher abundance of functional genes related to energy, lipid, amino acid metabolism, as well as terpenoids and polyketides metabolism, xenobiotics biodegradation and metabolism compared to the gut. Despite differences among classes, the total abundance of bacteriocins was similar in both gut and skin microbiomes, which is significant in shaping microbial communities due to their antimicrobial properties. A better knowledge of seahorse microbiomes benefits conservation and sustainable aquaculture efforts, offering insights into habitat protection, disease management, and optimizing aquaculture environments, thereby promoting seahorse health and welfare while minimizing environmental impact and enhancing aquaculture sustainability.

3.
mBio ; : e0072624, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38847540

ABSTRACT

The modulation of actin polymerization is a common theme among microbial pathogens. Even though microorganisms show a wide repertoire of strategies to subvert the activity of actin, most of them converge in the ones that activate nucleating factors, such as the Arp2/3 complex. Brucella spp. are intracellular pathogens capable of establishing chronic infections in their hosts. The ability to subvert the host cell response is dependent on the capacity of the bacterium to attach, invade, avoid degradation in the phagocytic compartment, replicate in an endoplasmic reticulum-derived compartment and egress. Even though a significant number of mechanisms deployed by Brucella in these different phases have been identified and characterized, none of them have been described to target actin as a cellular component. In this manuscript, we describe the identification of a novel virulence factor (NpeA) that promotes niche formation. NpeA harbors a short linear motif (SLiM) present within an amphipathic alpha helix that has been described to bind the GTPase-binding domain (GBD) of N-WASP and stabilizes the autoinhibited state. Our results show that NpeA is secreted in a Type IV secretion system-dependent manner and that deletion of the gene diminishes the intracellular replication capacity of the bacterium. In vitro and ex vivo experiments demonstrate that NpeA binds N-WASP and that the short linear motif is required for the biological activity of the protein.IMPORTANCEThe modulation of actin-binding effectors that regulate the activity of this fundamental cellular protein is a common theme among bacterial pathogens. The neural Wiskott-Aldrich syndrome protein (N-WASP) is a protein that several pathogens target to hijack actin dynamics. The highly adapted intracellular bacterium Brucella has evolved a wide repertoire of virulence factors that modulate many activities of the host cell to establish successful intracellular replication niches, but, to date, no effector proteins have been implicated in the modulation of actin dynamics. We present here the identification of a virulence factor that harbors a short linear motif (SLiM) present within an amphipathic alpha helix that has been described to bind the GTPase-binding domain (GBD) of N-WASP stabilizing its autoinhibited state. We demonstrate that this protein is a Type IV secretion effector that targets N-WASP-promoting intracellular survival and niche formation.

4.
Mar Biotechnol (NY) ; 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38864950

ABSTRACT

This study aimed to investigate the taxonomic and functional patterns of the microbiome associated with Barbour's seahorse (Hippocampus barbouri) using a combination of shotgun metagenomics and bioinformatics. The analyses revealed that Pseudomonadota and Bacillota were the dominant phyla in the seahorse skin microbiome, whereas Pseudomonadota and, to a lesser extent, Bacillota and Bacteroidota were the dominant phyla in the seahorse gut microbiome. Several metabolic pathway categories were found to be enriched in the skin microbiome, including amino acid metabolism, carbohydrate metabolism, cofactor and vitamin metabolism, energy metabolism, nucleotide metabolism, as well as membrane transport, signal transduction, and cellular community-prokaryotes. In contrast, the gut microbiome exhibited enrichment in metabolic pathways associated with the metabolism of terpenoids and polyketides, biosynthesis of other secondary metabolites, xenobiotics biodegradation and metabolism, and quorum sensing. Additionally, although the relative abundance of bacteriocins in the skin and gut was slightly similar, notable differences were observed at the class level. Specifically, class I bacteriocins were found to be more abundant in the skin microbiome, whereas class III bacteriocins were more abundant in the gut microbiome. To the best of our knowledge, this study represents the first comprehensive examination of the taxonomic and functional patterns of the skin and gut microbiome in Barbour's seahorse. These findings can greatly contribute to a deeper understanding of the seahorse-associated microbiome, which can play a pivotal role in predicting and controlling bacterial infections, thereby contributing to the success of aquaculture and health-promoting initiatives.

5.
Am J Transplant ; 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38866110

ABSTRACT

Medical literature highlights differences in liver transplantation (LT) waitlist experiences among ABO blood types. Type AB candidates reportedly have higher LT rates and reduced mortality. Despite liver offering guidelines, ABO disparities persist. This study examines LT access discrepancies among blood types, focusing on type AB, and seeks equitable strategies. Using the United Network for Organ Sharing database (2003-2022), 170 276 waitlist candidates were retrospectively analyzed. Dual predictive analyses (LT opportunity and survival studies) evaluated 1-year recipient pool survival, considering waitlist and post-LT survival, alongside anticipated allocation value per recipient, under 6 scenarios. Of the cohort, 97 670 patients (57.2%) underwent LT. Type AB recipients had the highest LT rate (73.7% vs 55.2% for O), shortest median waiting time (90 vs 198 days for A), and lowest waitlist mortality (12.9% vs 23.9% for O), with the lowest median model for end-stage liver disease-sodium (MELD-Na) score (20 vs 25 for A/O). The LT opportunity study revealed that reallocating type A (or A and O) donors originally for AB recipients to A recipients yielded the greatest reduction in disparities in anticipated value per recipient, from 0.19 (before modification) to 0.08. Meanwhile, the survival study showed that ABO-identical LTs reduced disparity the most (3.5% to 2.8%). Sensitivity analysis confirmed these findings were specific to the MELD-Na score < 30 population, indicating current LT allocation may favor certain blood types. Prioritizing ABO-identical LTs for MELD-Na score < 30 recipients could ensure uniform survival outcomes and mitigate disparities.

7.
Transplant Direct ; 10(7): e1657, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38881743

ABSTRACT

Background: The role of donor age in liver transplantation (LT) outcomes for hepatocellular carcinoma (HCC) is controversial. Given the significant risk of HCC recurrence post-LT, optimizing donor/recipient matching is crucial. This study reassesses the impact of young donors on LT outcomes in patients with HCC. Methods: A retrospective review of 11 704 LT cases from the United Network for Organ Sharing database (2012-2021) was conducted. The study focused on the effect of donor age on recurrence-free survival, using hazard associated with LT for HCC (HALT-HCC) and Metroticket 2.0 scores to evaluate post-LT survival in patients with HCC. Results: Of 4706 cases with young donors, 11.0% had HCC recurrence or death within 2 y, and 18.3% within 5 y. These outcomes were comparable with those of non-young donors. A significant correlation between donor age and post-LT recurrence or mortality (P = 0.04) was observed, which became statistically insignificant after tumor-related adjustments (P = 0.32). The Kaplan-Meier curve showed that recipients with lower HALT-HCC scores (<9) and Metroticket 2.0 scores (<2.2) significantly benefited from young donors, unlike those exceeding these score thresholds. Cox regression analysis showed that donor age significantly influenced outcomes in recipients below certain score thresholds but was less impactful for higher scores. Conclusions: Young donors are particularly beneficial for LT recipients with less aggressive HCC, as indicated by their HALT-HCC and Metroticket 2.0 scores. These findings suggest strategically allocating young donors to recipients with less aggressive tumor profiles, which could foster more efficient use of the scarce donor supply and potentially enhance post-LT outcomes.

8.
HPB (Oxford) ; 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38879433

ABSTRACT

BACKGROUND: Cause of death (COD) is a predictor of liver transplant (LT) outcomes independent of donor age, yet has not been recently reappraised. METHODS: Analyzing UNOS database (2013-2022), the study explored COD trends and impacts on one-year post-LT graft survival (GS) and hazard ratios (HR) for graft failure. RESULTS: Of 80,282 brain-death donors, 55,413(69.0%) underwent initial LT. Anoxia became the predominant COD in 2015, increasing from 29.0% in 2013 to 45.1% in 2021, with notable increases in drug intoxication. Survival differences between anoxia and cerebrovascular accidents (CVA) recently became insignificant (P=0.95). Further analysis showed improved GS from intracranial hemorrhage/stroke (previously worse; P<0.01) (P=0.70). HRs for post-1-year graft failure showed reduced significance of CVA (vs.Anoxia) and intracranial hemorrhage/stroke (vs.any other COD) recently. Donors with intracranial hemorrhage/stroke, showing improved survival and HR, were allocated to recipients with lower MELD-Na, contrasting the trend for drug intoxication CODs. DISCUSSION: CVA, traditionally linked with poorer outcomes, shows improved GS and HRs (vs.Anoxia). This could be due to rising drug intoxication cases and the allocation of donors with drug intoxication to recipients with higher MELD-Na, and those with CVA to recipients with lower scores. While COD remains crucial in donor selection, proper matching can mitigate differences among CODs.

9.
Pediatr Surg Int ; 40(1): 120, 2024 May 04.
Article in English | MEDLINE | ID: mdl-38702423

ABSTRACT

PURPOSE: To assess the neurodevelopment outcomes of children younger than 42 months of age with intestinal failure (IF) using prolonged parenteral nutrition (PN) followed by a Pediatric Multidisciplinary Intestinal Rehabilitation Program from a public tertiary hospital in Brazil. METHODS: Bayley III scale was administered in children aged 2 to 42 months with IF and receiving PN for more than 60 days. Composite scores in cognitive, motor, and language domains were analyzed. Developmental delay was defined as a performance 2 standard deviations (SD) below the average at the 3 domains. Association between Bayley III composite scores and clinical variables related to IF were tested. RESULTS: Twenty-four children with median (IQR) age of 17.5 months (9-28.5) were studied, 58.3% were male. Developmental delay was found in 34%, 33% and 27% of the patients in cognitive, motor, and language domains, respectively. There was no significant association between the Bayley-III composite scores and length of hospitalization, prematurity, and number of surgical procedures with anesthesia. CONCLUSION: The study demonstrated impairments in the cognitive, motor and language domains in approximately one-third of young patients with IF on prolonged PN.


Subject(s)
Intestinal Failure , Parenteral Nutrition , Humans , Male , Female , Brazil/epidemiology , Infant , Parenteral Nutrition/methods , Parenteral Nutrition/statistics & numerical data , Child, Preschool , Developmental Disabilities/etiology , Neurodevelopmental Disorders/epidemiology , Neurodevelopmental Disorders/etiology
10.
Pediatr Transplant ; 28(5): e14781, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38808744

ABSTRACT

The International Pediatric Transplant Association convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorders (PTLD) after pediatric solid organ transplantation. This report addresses the outcomes of deliberations by the PTLD Management Working Group. A strong recommendation was made for reduction in immunosuppression as the first step in management. Similarly, strong recommendations were made for the use of the anti-CD20 monoclonal antibody (rituximab) as was the case for chemotherapy in selected scenarios. In some scenarios, there is uncoupling of the strength of the recommendations from the available evidence in situations where such evidence is lacking but collective clinical experiences drive decision-making. Of note, there are no large, randomized phase III trials of any treatment for PTLD in the pediatric age group. Current gaps and future research priorities are highlighted.


Subject(s)
Lymphoproliferative Disorders , Organ Transplantation , Postoperative Complications , Rituximab , Humans , Lymphoproliferative Disorders/etiology , Lymphoproliferative Disorders/diagnosis , Lymphoproliferative Disorders/therapy , Child , Adolescent , Rituximab/therapeutic use , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Postoperative Complications/diagnosis , Immunosuppressive Agents/therapeutic use , Child, Preschool
11.
Liver Transpl ; 2024 May 13.
Article in English | MEDLINE | ID: mdl-38727618

ABSTRACT

There is no recent update on the clinical course of retransplantation (re-LT) after living donor liver transplantation (LDLT) in the US using recent national data. The UNOS database (2002-2023) was used to explore patient characteristics in initial LT, comparing deceased donor liver transplantation (DDLT) and LDLT for graft survival (GS), reasons for graft failure, and GS after re-LT. It assesses waitlist dropout and re-LT likelihood, categorizing re-LT cohort based on time to re-listing as acute or chronic (≤ or > 1 mo). Of 132,323 DDLT and 5955 LDLT initial transplants, 3848 DDLT and 302 LDLT recipients underwent re-LT. Of the 302 re-LT following LDLT, 156 were acute and 146 chronic. Primary nonfunction (PNF) was more common in DDLT, although the difference was not statistically significant (17.4% vs. 14.8% for LDLT; p = 0.52). Vascular complications were significantly higher in LDLT (12.5% vs. 8.3% for DDLT; p < 0.01). Acute re-LT showed a larger difference in primary nonfunction between DDLT and LDLT (49.7% vs. 32.0%; p < 0.01). Status 1 patients were more common in DDLT (51.3% vs. 34.0% in LDLT; p < 0.01). In the acute cohort, Kaplan-Meier curves indicated superior GS after re-LT for initial LDLT recipients in both short-term and long-term ( p = 0.02 and < 0.01, respectively), with no significant difference in the chronic cohort. No significant differences in waitlist dropout were observed, but the initial LDLT group had a higher re-LT likelihood in the acute cohort (sHR 1.40, p < 0.01). A sensitivity analysis focusing on the most recent 10-year cohort revealed trends consistent with the overall study findings. LDLT recipients had better GS in re-LT than DDLT. Despite a higher severity of illness, the DDLT cohort was less likely to undergo re-LT.

13.
Microb Biotechnol ; 17(4): e14464, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38635123

ABSTRACT

In this opinion, we discuss the role of tRNAs in phage biology and their importance in DNA replication and phage-host interactions. Phages are a diverse group of obligate bacterial viruses that possess genomes with a wide range of sizes. Among them, we find phages with few genes that depend entirely on their host's translational machinery for replication. However, some phages carry genes for all replication steps and even contain genes for their own translational synthesis. In these cases, the integration of tRNA genes in their genomes is not completely understood, generating different theories about their presence and function during the replication cycle. Although different studies have attempted to elucidate their role, additional studies are needed to clarify the presence and significance of tRNA genes in phages. Moreover, we highlight the importance of tRNA genes in phages from both ecological and therapeutic perspectives.


Subject(s)
Bacteriophages , RNA, Transfer
14.
Sci Rep ; 14(1): 8062, 2024 04 05.
Article in English | MEDLINE | ID: mdl-38580720

ABSTRACT

In this randomised, placebo-controlled trial, adults with impaired sleep (Pittsburgh Sleep Quality Index ≥ 5) were randomly assigned using a minimization algorithm to receive a formulation containing L-theanine plus lemon balm, valerian, and saffron extracts, or placebo, during 6 weeks. Objective sleep quality parameters were measured using an actigraphy device. We enrolled and randomised 64 individuals, 31 from the active group and 27 from the placebo group completed the 6 week follow-up. Mean sleep efficiency remained unmodified in the active group, and increased by 3% in the placebo group, the between-group difference in the change was not statistically significant (p = 0.49). Total sleep time also improved more with placebo (13.0 vs. 1.33 min, p = 0.66). Time wake after sleep onset (WASO) decreased more in the active group (4.6% vs. 2.4%), but the difference was not significant (p = 0.33). Mean PSQI decreased by 3.11 points (32.3%) in the active group, and by 3.86 points (39.5%) in the placebo group (p = 0.41). SF-36 increased more with placebo (+ 18.3 in active, + 32.1 in placebo, p = 0.68). Salivary cortisol remained unchanged in both groups. No serious adverse events were reported. Among adults with impaired sleep, a nutraceutical combination did not improve objective or subjective sleep parameters more than a placebo infusion.


Subject(s)
Sleep Initiation and Maintenance Disorders , Sleep Quality , Adult , Humans , Sleep , Polysomnography , Actigraphy , Dietary Supplements , Double-Blind Method
15.
Nanomaterials (Basel) ; 14(8)2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38668173

ABSTRACT

This work reports on the design, development, and characterization of novel magneto-plasmonic elastic liposomes (MPELs) of DPPC:SP80 (85:15) containing Mg0.75Ca0.25Fe2O4 nanoparticles coupled with gold nanorods, for topical application of photothermal therapy (PTT). Both magnetic and plasmonic components were characterized regarding their structural, morphological, magnetic and photothermal properties. The magnetic nanoparticles display a cubic shape and a size (major axis) of 37 ± 3 nm, while the longitudinal and transverse sizes of the nanorods are 46 ± 7 nm and 12 ± 1.6 nm, respectively. A new methodology was employed to couple the magnetic and plasmonic nanostructures, using cysteine as bridge. The potential for photothermia was evaluated for the magnetic nanoparticles, gold nanorods and the coupled magnetic/plasmonic nanoparticles, which demonstrated a maximum temperature variation of 28.9 °C, 33.6 °C and 37.2 °C, respectively, during a 30 min NIR-laser irradiation of 1 mg/mL dispersions. Using fluorescence anisotropy studies, a phase transition temperature (Tm) of 35 °C was estimated for MPELs, which ensures an enhanced fluidity crucial for effective crossing of the skin layers. The photothermal potential of this novel nanostructure corresponds to a specific absorption rate (SAR) of 616.9 W/g and a maximum temperature increase of 33.5 °C. These findings point to the development of thermoelastic nanocarriers with suitable features to act as photothermal hyperthermia agents.

16.
Liver Transpl ; 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38625836

ABSTRACT

The use of older donors after circulatory death (DCD) for liver transplantation (LT) has increased over the past decade. This study examined whether outcomes of LT using older DCD (≥50 y) have improved with advancements in surgical/perioperative care and normothermic machine perfusion (NMP) technology. A total of 7602 DCD LT cases from the United Network for Organ Sharing database (2003-2022) were reviewed. The impact of older DCD donors on graft survival was assessed using the Kaplan-Meier and HR analyses. In all, 1447 LT cases (19.0%) involved older DCD donors. Although there was a decrease in their use from 2003 to 2014, a resurgence was noted after 2015 and reached 21.9% of all LTs in the last 4 years (2019-2022). Initially, 90-day and 1-year graft survivals for older DCDs were worse than younger DCDs, but this difference decreased over time and there was no statistical difference after 2015. Similarly, HRs for graft loss in older DCD have recently become insignificant. In older DCD LT, NMP usage has increased recently, especially in cases with extended donor-recipient distances, while the median time from asystole to aortic cross-clamp has decreased. Multivariable Cox regression analyses revealed that in the early phase, asystole to cross-clamp time had the highest HR for graft loss in older DCD LT without NMP, while in the later phases, the cold ischemic time (>5.5 h) was a significant predictor. LT outcomes using older DCD donors have become comparable to those from young DCD donors, with recent HRs for graft loss becoming insignificant. The strategic approach in the recent period could mitigate risks, including managing cold ischemic time (≤5.5 h), reducing asystole to cross-clamp time, and adopting NMP for longer distances. Optimal use of older DCD donors may alleviate the donor shortage.

17.
Pediatr Transplant ; 28(4): e14763, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38682750

ABSTRACT

BACKGROUND: Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disorders (PTLD) is the most common malignancy in children after transplant; however, difficulties for early detection may worsen the prognosis. METHODS: The prospective, multicenter, study enrolled 944 children (≤21 years of age). Of these, 872 received liver, heart, kidney, intestinal, or multivisceral transplants in seven US centers between 2014 and 2019 (NCT02182986). In total, 34 pediatric EBV+ PTLD (3.9%) were identified by biopsy. Variables included sex, age, race, ethnicity, transplanted organ, EBV viral load, pre-transplant EBV serology, immunosuppression, response to chemotherapy and rituximab, and histopathological diagnosis. RESULTS: The uni-/multivariable competing risk analyses revealed the combination of EBV-seropositive donor and EBV-naïve recipient (D+R-) was a significant risk factor for PTLD development (sub-hazard ratio: 2.79 [1.34-5.78], p = .006) and EBV DNAemia (2.65 [1.72-4.09], p < .001). Patients with D+R- were significantly more associated with monomorphic/polymorphic PTLD than those with the other combinations (p = .02). Patients with monomorphic/polymorphic PTLD (n = 21) had significantly more EBV DNAemia than non-PTLD patients (p < .001) and an earlier clinical presentation of PTLD than patients with hyperplasias (p < .001), within 6-month post-transplant. Among non-liver transplant recipients, monomorphic/polymorphic PTLD were significantly more frequent than hyperplasias in patients ≥5 years of age at transplant (p = .01). CONCLUSIONS: D+R- is a risk factor for PTLD and EBV DNAemia and associated with the incidence of monomorphic/polymorphic PTLD. Intensive follow-up of EBV viral load within 6-month post-transplant, especially for patients with D+R- and/or non-liver transplant recipients ≥5 years of age at transplant, may help detect monomorphic/polymorphic PTLD early in pediatric transplant.


Subject(s)
Epstein-Barr Virus Infections , Lymphoproliferative Disorders , Organ Transplantation , Postoperative Complications , Humans , Lymphoproliferative Disorders/etiology , Lymphoproliferative Disorders/epidemiology , Lymphoproliferative Disorders/virology , Epstein-Barr Virus Infections/epidemiology , Male , Prospective Studies , Child , Female , United States/epidemiology , Child, Preschool , Adolescent , Infant , Organ Transplantation/adverse effects , Postoperative Complications/epidemiology , Postoperative Complications/virology , Postoperative Complications/etiology , Risk Factors , Herpesvirus 4, Human , Young Adult
18.
Nat Cell Biol ; 26(4): 519-529, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38570617

ABSTRACT

Localized sources of morphogens, called signalling centres, play a fundamental role in coordinating tissue growth and cell fate specification during organogenesis. However, how these signalling centres are established in tissues during embryonic development is still unclear. Here we show that the main signalling centre orchestrating development of rodent incisors, the enamel knot (EK), is specified by a cell proliferation-driven buildup in compressive stresses (mechanical pressure) in the tissue. Direct mechanical measurements indicate that the stresses generated by cell proliferation are resisted by the surrounding tissue, creating a circular pattern of mechanical anisotropy with a region of high compressive stress at its centre that becomes the EK. Pharmacological inhibition of proliferation reduces stresses and suppresses EK formation, and application of external pressure in proliferation-inhibited conditions rescues the formation of the EK. Mechanical information is relayed intracellularly through YAP protein localization, which is cytoplasmic in the region of compressive stress that establishes the EK and nuclear in the stretched anisotropic cells that resist the pressure buildup around the EK. Together, our data identify a new role for proliferation-driven mechanical compression in the specification of a model signalling centre during mammalian organ development.


Subject(s)
Incisor , Signal Transduction , Animals , Female , Pregnancy , Cell Differentiation , Mammals , Cell Proliferation , Stress, Mechanical
19.
Cient. dent. (Ed. impr.) ; 21(1): 1-8, abr.-2024. ilus
Article in Spanish | IBECS | ID: ibc-232709

ABSTRACT

Introducción: la patología sinusal puede comprometer el éxito del tratamiento de implantes. Existe una elevada incidencia de patología sinusal. El tratamiento de esta patología puede implicar a otros profesionales, lo que supone un mayor coste sanitarios y demora en la realización de los tratamientos de implantes. El objetivo del presente artículo es presentar un caso clínico representativo de la patología pseudoquística del seno maxilar y una alternativa de su manejo quirúrgico simultáneo a la regeneración ósea requerida para su posterior rehabilitación mediante implantes, así como actualizar la evidencia científica disponible. Caso clínico: se presenta una paciente de 46 años con una lesión pseudoquística sinusal que es remitida para rehabilitar mediante implantes en 1.4 y 1.7, por movilidad y dolor en relación a prótesis fija dentosoportada en maxilar derecho. Se realiza el tratamiento quirúrgico de exodoncias, elevación de seno maxilar y eliminación de la lesión pseudoquística de manera simultánea. Discusión: existe controversia sobre el momento idóneo para realizar el tratamiento sinusal. Algunos estudios muestran éxito de la cirugía endoscópica simultáneamente a la eliminación de la fuente odontogénica. Otros han demostrado que realizar primero la cirugía sinusal tiene el mismo porcentaje de curación que realizar primero el tratamiento odontológico. Conclusión: el diagnóstico de la patología y la planificación quirúrgica deben tener en cuenta el tipo de patología, la extensión y las necesidades de tratamiento del paciente. El manejo quirúrgico de la patología sinusal de manera simultánea a la regeneración ósea es una alternativa segura y beneficiosa para el paciente. (AU)


Introduction: Sinus pathology can compromise the success of implant treatment. There is a high incidence of sinus pathology. The treatment of this pathology may involve other professionals, which means higher healthcare costs and delays in carrying out implant treatments. Besides updating available scientific evidence, the objective of this article is to present a representative clinical case of pseudocystic pathology of the maxillary sinus and an alternative to its simultaneous surgical management in the bone regeneration required for subsequent rehabilitation using implants. Clinical case: A 46-year-old patient with a pseudocystic sinus lesion, referred for rehabilitation using implants in 1.4 and 1.7, due to mobility and pain in relation to a tooth-supported fixed prosthesis in the right maxilla. The surgical treatment, consisting of extractions, maxillary sinus elevation and removal of the pseudocystic lesion, was performed simultaneously. Discussion: There is controversy about the ideal time to perform sinus treatment. Some studies show success of endoscopic surgery simultaneously with removal of the odontogenic source. Others have shown that performing sinus surgery first has the same cure rate as performing dental treatment first. Conclusion: Pathology diagnosis and surgical planning must take into account the type and extent of the pathology and the treatment needs of the patient. Surgical management of sinus pathology simultaneously with bone regeneration is a safe and beneficial alternative for the patient. (AU)


Subject(s)
Humans , Female , Adult , Cysts , Maxillary Sinus , Sinoatrial Node , Dental Implants , Pathology, Oral
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