Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 256
Filtrar
1.
Thyroid ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717947

RESUMEN

BACKGROUND: Long-term management of intermediate- and high-risk differentiated thyroid cancer (DTC) involves thyrotropin (TSH) suppression with thyroid hormone to prevent potential stimulation of TSH receptors on DTC cells, leading to tumor growth. However, the current guidelines recommending TSH suppression are based on low-to-moderate quality evidence. METHODS: We performed a systematic review and meta-analysis of studies evaluating the role of TSH suppression in intermediate- and high-risk DTC patients (≥18 years) treated as per regional guideline-based therapy with a follow-up duration of 5 years (PROSPERO #252396). TSH suppression was defined as 'below normal reference range' or, when known, <0.5 mIU/L. Primary outcome measures included A. composite of progression-free survival (PFS), disease-free survival (DFS), and relapse-free survival (RLFS), and B. composite of disease-specific survival (DSS), and overall survival (OS). Secondary outcome included a composite of cardiac or skeletal adverse events. All outcomes and comparisons were represented as TSH suppression versus TSH non-suppression. Randomized controlled trials, cohort studies, and case-control studies were included for analysis. Pooled hazard ratio (HR) and 95% confidence interval (CI) were calculated using random-effects model. RESULTS: Abstract screening was performed on 6,369 studies. After the exclusion of irrelevant studies and full-text screening, 9 studies were selected for the final meta-analysis. Based on 7 studies (3,591 patients), the composite outcome of PFS, DFS, and RLFS was not significantly different between TSH suppression and non-suppression groups (HR: 0.75; 95% CI: 0.48 - 1.17; I2=76%). Similarly, a DSS and OS composite outcome assessment based on 4 studies (3,616 patients) did not favor TSH suppression (HR: 0.69; 95% CI: 0.31 - 1.52; I2 = 88%). Even after excluding studies of lower quality, the primary outcomes were not significantly different between the TSH suppression and non-suppression cohorts. The secondary outcome, obtained from 2 studies (1,294 patients), was significantly higher in the TSH-suppressed groups (HR: 1.82; 95% CI: 1.30 - 2.55; I2 = 0%). Significant study heterogeneity was noted for primary outcomes. CONCLUSION: TSH suppression in intermediate- and high-risk DTC may not improve survival outcomes but may increase the risk of secondary complications. However, the limited evidence and study heterogeneity warrant cautious interpretation of our findings.

2.
Hepatol Commun ; 8(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38619432

RESUMEN

BACKGROUND: Alcohol cessation is the only intervention that both prevents and halts the progressions of alcohol-associated liver disease. The aim of this study was to assess the relationship between a return to alcohol use and consultation with hepatology in treatment-seeking patients with alcohol use disorder (AUD). METHODS: Two hundred forty-two patients with AUD were enrolled in an inpatient treatment program, with hepatology consultation provided for 143 (59%) patients at the request of the primary team. Patients not seen by hepatology served as controls. The primary outcome was any alcohol use after discharge assessed using AUDIT-C at 26 weeks after discharge. RESULTS: For the primary endpoint, AUDIT at week 26, 61% of the hepatology group and 28% of the controls completed the questionnaire (p=0.07). For the secondary endpoint at week 52, these numbers were 22% and 11% (p = 0.6). At week 26, 39 (45%) patients in the hepatology group versus 31 (70%) controls (p = 0.006) returned to alcohol use. Patients evaluated by hepatology had decreased rates of hazardous alcohol use compared to controls, with 36 (41%) versus 29 (66%) (p = 0.008) of the patients, respectively, reporting hazardous use. There were no significant differences in baseline characteristics between groups and no difference in rates of prescribing AUD therapy. There was no difference in outcomes at 52 weeks. CONCLUSIONS: Patients evaluated by hepatology had significantly lower rates of return to alcohol use and lower rates of hazardous drinking at 26 weeks but not at 52 weeks. These findings suggest that hepatology evaluation during inpatient treatment of AUD may lead to decreased rates of early return to alcohol use.


Asunto(s)
Alcoholismo , Gastroenterología , Hepatopatías Alcohólicas , Humanos , Alcoholismo/epidemiología , Alcoholismo/terapia , Alta del Paciente , Pacientes Internos , Hepatopatías Alcohólicas/terapia , Derivación y Consulta
3.
Elife ; 132024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38591541

RESUMEN

Collective cell migration is fundamental for the development of organisms and in the adult for tissue regeneration and in pathological conditions such as cancer. Migration as a coherent group requires the maintenance of cell-cell interactions, while contact inhibition of locomotion (CIL), a local repulsive force, can propel the group forward. Here we show that the cell-cell interaction molecule, N-cadherin, regulates both adhesion and repulsion processes during Schwann cell (SC) collective migration, which is required for peripheral nerve regeneration. However, distinct from its role in cell-cell adhesion, the repulsion process is independent of N-cadherin trans-homodimerisation and the associated adherens junction complex. Rather, the extracellular domain of N-cadherin is required to present the repulsive Slit2/Slit3 signal at the cell surface. Inhibiting Slit2/Slit3 signalling inhibits CIL and subsequently collective SC migration, resulting in adherent, nonmigratory cell clusters. Moreover, analysis of ex vivo explants from mice following sciatic nerve injury showed that inhibition of Slit2 decreased SC collective migration and increased clustering of SCs within the nerve bridge. These findings provide insight into how opposing signals can mediate collective cell migration and how CIL pathways are promising targets for inhibiting pathological cell migration.


Asunto(s)
Cadherinas , Movimiento Celular , Inhibición de Contacto , Péptidos y Proteínas de Señalización Intercelular , Proteínas de la Membrana , Regeneración Nerviosa , Proteínas del Tejido Nervioso , Células de Schwann , Células de Schwann/metabolismo , Células de Schwann/fisiología , Animales , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Ratones , Cadherinas/metabolismo , Cadherinas/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/genética , Regeneración Nerviosa/fisiología , Locomoción/fisiología , Adhesión Celular , Transducción de Señal
4.
Aliment Pharmacol Ther ; 59(9): 1020-1032, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38497159

RESUMEN

BACKGROUND AND AIMS: The Fontan palliation is the final stage of surgery for many children born with univentricular physiology. Almost all Fontan patients develop liver fibrosis which may eventually lead to cirrhosis and hepatocellular carcinoma (HCC). These are important causes of morbidity and mortality in these patients. We performed a systematic review and meta-analysis to assess the incidence of cirrhosis and HCC in Fontan patients and stratify it based on time since surgery. METHODS: A literature search of seven databases identified 1158 records. Studies reporting the number of cirrhosis and HCC cases in Fontan patients and time since Fontan surgery were included. In the cirrhosis cohort, we included only those studies where all patients underwent liver biopsy. RESULTS: A total of 23 studies were included: 12 and 13 studies in the cirrhosis and HCC cohorts, respectively, with two studies included in both cohorts. The incidence of cirrhosis was 0.97 per 100 patient-years (95% CI 0.57-1.63), with the incidence and cumulative incidence ≥20 years post Fontan surgery being 1.61 per 100 patient-years (95% CI 1.24-2.08) and 32.2% (95% CI 25.8%-39.4%), respectively. The incidence of HCC was 0.12 per 100 patient-years (95% CI 0.07-0.21), with the incidence and cumulative incidence ≥20 years post Fontan surgery being 0.20 per 100 patient-years (95% CI 0.12-0.35) and 3.9% (95% CI 2.2%-6.8%), respectively. Only about 70% of patients with HCC (20/28) had underlying cirrhosis. CONCLUSION: The incidence of cirrhosis and HCC increases over time, especially at ≥20 years post Fontan surgery. Studies are needed to further identify at-risk patients in order to streamline surveillance for these highly morbid conditions.


Asunto(s)
Carcinoma Hepatocelular , Procedimiento de Fontan , Neoplasias Hepáticas , Niño , Humanos , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/cirugía , Incidencia , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/cirugía , Procedimiento de Fontan/efectos adversos , Cirrosis Hepática/etiología , Cirrosis Hepática/complicaciones , Factores de Riesgo
5.
Nat Commun ; 15(1): 1284, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38346966

RESUMEN

The 2002 SARS outbreak, the 2019 emergence of COVID-19, and the continuing evolution of immune-evading SARS-CoV-2 variants together highlight the need for a broadly protective vaccine against ACE2-utilizing sarbecoviruses. While updated variant-matched formulations are a step in the right direction, protection needs to extend beyond SARS-CoV-2 and its variants to include SARS-like viruses. Here, we introduce bivalent and trivalent vaccine formulations using our spike protein nanoparticle platform that completely protect female hamsters against BA.5 and XBB.1 challenges with no detectable virus in the lungs. The trivalent cocktails elicit highly neutralizing responses against all tested Omicron variants and the bat sarbecoviruses SHC014 and WIV1. Finally, our 614D/SHC014/XBB trivalent spike formulation completely protects human ACE2-transgenic female hamsters against challenges with WIV1 and SHC014 with no detectable virus in the lungs. Collectively, these results illustrate that our trivalent protein-nanoparticle cocktail can provide broad protection against SARS-CoV-2-like and SARS-CoV-1-like sarbecoviruses.


Asunto(s)
Nanovacunas , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Cricetinae , Humanos , Femenino , Enzima Convertidora de Angiotensina 2 , Vacunación , Inmunización , Anticuerpos Neutralizantes , Anticuerpos Antivirales
6.
Sci Rep ; 14(1): 2221, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38278973

RESUMEN

Social recognition is crucial for survival in social species, and necessary for group living, selective reproduction, pair bonding, and dominance hierarchies. Mice and rats are the most commonly used animal models in social memory research, however current paradigms do not account for the complex social dynamics they exhibit in the wild. To assess the range of social memories being studied, we conducted a systematic analysis of neuroscience articles testing the social memory of mice and rats published within the past two decades and analyzed their methods. Our results show that despite these rodent's rich social memory capabilities, the majority of social recognition papers explore short-term memories and short-term familiarity levels with minimal exposure between subject and familiar stimuli-a narrow type of social memory. We have identified several key areas currently understudied or underrepresented: kin relationships, mates, social ranks, sex variabilities, and the effects of aging. Additionally, reporting on social stimulus variables such as housing history, strain, and age, is limited, which may impede reproducibility. Overall, our data highlight large gaps in the diversity of social memories studied and the effects social variables have on social memory mechanisms.


Asunto(s)
Memoria a Corto Plazo , Reconocimiento en Psicología , Conducta Social , Animales , Ratas , Reproducibilidad de los Resultados , Predominio Social , Ratones
7.
mBio ; 15(1): e0285723, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38051116

RESUMEN

IMPORTANCE: Bacteria are constantly exchanging DNA, which constitutes horizontal gene transfer. While some of these occurs by a non-specific process called natural transformation, some occurs by a specific mating between a donor and a recipient cell. In specific conjugation, the mating pilus is extended from the donor cell to make contact with the recipient cell, but whether DNA is actually transferred through this pilus or by another mechanism involving the type IV secretion system complex without the pilus has been an open question. Using Escherichia coli, we show that DNA can be transferred through this pilus between a donor and a recipient cell that has not established a tight mating junction, providing a new picture for the role of this pilus.


Asunto(s)
Escherichia coli , Transferencia de Gen Horizontal , Escherichia coli/genética , Escherichia coli/metabolismo , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Conjugación Genética , Fimbrias Bacterianas/genética , Fimbrias Bacterianas/metabolismo , Plásmidos
8.
Pract Neurol ; 24(2): 129-133, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-37875347

RESUMEN

A 54-year-old man developed altered mental state and generalised tonic-clonic seizures after 1 week of upper respiratory tract symptoms and diarrhoea, having been previously well. His MR scan of brain showed multifocal progressive T2 cortical signal changes. He was diagnosed with new-onset refractory status epilepticus (NORSE), initially treated as being secondary to autoimmune/paraneoplastic limbic encephalitis, although subsequent investigations were negative. His seizures and electrographic epileptiform activity continued despite escalating doses of antiseizure medications, immunosuppression with corticosteroids, immunoglobulins, plasma exchange and rituximab, and thereafter anaesthetic agents. A vagus nerve stimulator (VNS) was implanted 6 weeks after admission and its voltage rapidly increased over 4 days; his seizure activity resolved in the third week after VNS implantation. This case highlights the role of VNS in the early management of NORSE.


Asunto(s)
Estado Epiléptico , Estimulación del Nervio Vago , Masculino , Humanos , Persona de Mediana Edad , Estado Epiléptico/terapia , Estado Epiléptico/diagnóstico , Convulsiones , Encéfalo , Terapia de Inmunosupresión , Resultado del Tratamiento
9.
Microsc Microanal ; 29(6): 2127-2148, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-37966978

RESUMEN

Cellular neurobiology has benefited from recent advances in the field of cryo-electron tomography (cryo-ET). Numerous structural and ultrastructural insights have been obtained from plunge-frozen primary neurons cultured on electron microscopy grids. With most primary neurons having been derived from rodent sources, we sought to expand the breadth of sample availability by using primary neurons derived from 3rd instar Drosophila melanogaster larval brains. Ultrastructural abnormalities were encountered while establishing this model system for cryo-ET, which were exemplified by excessive membrane blebbing and cellular fragmentation. To optimize neuronal samples, we integrated substrate selection, micropatterning, montage data collection, and chemical fixation. Efforts to address difficulties in establishing Drosophila neurons for future cryo-ET studies in cellular neurobiology also provided insights that future practitioners can use when attempting to establish other cell-based model systems.


Asunto(s)
Drosophila melanogaster , Neuronas , Animales , Neuronas/ultraestructura , Tomografía con Microscopio Electrónico/métodos , Microscopía por Crioelectrón/métodos
10.
Proc Natl Acad Sci U S A ; 120(49): e2316668120, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38011558

RESUMEN

Type IV pili (T4P) are ubiquitous in both bacteria and archaea. They are polymers of the major pilin protein, which has an extended and protruding N-terminal helix, α1, and a globular C-terminal domain. Cryo-EM structures have revealed key differences between the bacterial and archaeal T4P in their C-terminal domain structure and in the packing and continuity of α1. This segment forms a continuous α-helix in archaeal T4P but is partially melted in all published bacterial T4P structures due to a conserved helix breaking proline at position 22. The tad (tight adhesion) T4P are found in both bacteria and archaea and are thought to have been acquired by bacteria through horizontal transfer from archaea. Tad pilins are unique among the T4 pilins, being only 40 to 60 residues in length and entirely lacking a C-terminal domain. They also lack the Pro22 found in all high-resolution bacterial T4P structures. We show using cryo-EM that the bacterial tad pilus from Caulobacter crescentus is composed of continuous helical subunits that, like the archaeal pilins, lack the melted portion seen in other bacterial T4P and share the packing arrangement of the archaeal T4P. We further show that a bacterial T4P, the Vibrio cholerae toxin coregulated pilus, which lacks Pro22 but is not in the tad family, has a continuous N-terminal α-helix, yet its α1 s are arranged similar to those in other bacterial T4P. Our results highlight the role of Pro22 in helix melting and support an evolutionary relationship between tad and archaeal T4P.


Asunto(s)
Proteínas Fimbrias , Fimbrias Bacterianas , Proteínas Fimbrias/genética , Proteínas Fimbrias/química , Fimbrias Bacterianas/metabolismo , Archaea/genética , Archaea/metabolismo , Bacterias/metabolismo
11.
BMC Genomics ; 24(1): 559, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37730546

RESUMEN

In Alzheimer's Disease (AD) and other dementias, hippocampal synaptic dysfunction and loss contribute to the progression of memory impairment. Recent analysis of human AD transcriptomes has provided a list of gene candidates that may serve as drivers of disease. One such candidate is the membrane protein TMEM184B. To evaluate whether TMEM184B contributes to neurological impairment, we asked whether loss of TMEM184B in mice causes gene expression or behavior alterations, focusing on the hippocampus. Because one major risk factor for AD is age, we compared young adult (5-month-old) and aged (15-month-old) wild type and Tmem184b-mutant mice to assess the dual contributions of age and genotype. TMEM184B loss altered expression of pre- and post-synaptic transcripts by 5 months and continued through 15 months, specifically affecting genes involved in synapse assembly and neural development. Wnt-activated enhancer elements were enriched among differentially expressed genes, suggesting an intersection with this pathway. Few differences existed between young adult and aged mutants, suggesting that transcriptional effects of TMEM184B loss are relatively constant. To understand how TMEM184B disruption may impact behaviors, we evaluated memory using the novel object recognition test and anxiety using the elevated plus maze. Young adult Tmem184b-mutant mice show normal object discrimination, suggesting a lack of memory impairment at this age. However, mutant mice showed decreased anxiety, a phenotype seen in some neurodevelopmental disorders. Taken together, our data suggest that TMEM184B is required for proper synaptic gene expression and anxiety-related behavior and is more likely to be linked to neurodevelopmental disorders than to dementia.


Asunto(s)
Enfermedad de Alzheimer , Redes Reguladoras de Genes , Humanos , Adulto Joven , Animales , Ratones , Lactante , Genotipo , Hipocampo , Proteínas de la Membrana/genética
12.
Nat Methods ; 20(10): 1537-1543, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37723245

RESUMEN

Imaging large fields of view while preserving high-resolution structural information remains a challenge in low-dose cryo-electron tomography. Here we present robust tools for montage parallel array cryo-tomography (MPACT) tailored for vitrified specimens. The combination of correlative cryo-fluorescence microscopy, focused-ion-beam milling, substrate micropatterning, and MPACT supports studies that contextually define the three-dimensional architecture of cells. To further extend the flexibility of MPACT, tilt series may be processed in their entirety or as individual tiles suitable for sub-tomogram averaging, enabling efficient data processing and analysis.


Asunto(s)
Tomografía con Microscopio Electrónico , Microscopía por Crioelectrón/métodos , Tomografía con Microscopio Electrónico/métodos , Microscopía Fluorescente/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...