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1.
Cell Stem Cell ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38733993

RESUMO

Enteroendocrine cells (EECs) secrete serotonin (enterochromaffin [EC] cells) or specific peptide hormones (non-EC cells) that serve vital metabolic functions. The basis for terminal EEC diversity remains obscure. By forcing activity of the transcription factor (TF) NEUROG3 in 2D cultures of human intestinal stem cells, we replicated physiologic EEC differentiation and examined transcriptional and cis-regulatory dynamics that culminate in discrete cell types. Abundant EEC precursors expressed stage-specific genes and TFs. Before expressing pre-terminal NEUROD1, post-mitotic precursors oscillated between transcriptionally distinct ASCL1+ and HES6hi cell states. Loss of either factor accelerated EEC differentiation substantially and disrupted EEC individuality; ASCL1 or NEUROD1 deficiency had opposing consequences on EC and non-EC cell features. These TFs mainly bind cis-elements that are accessible in undifferentiated stem cells, and they tailor subsequent expression of TF combinations that underlie discrete EEC identities. Thus, early TF oscillations retard EEC maturation to enable accurate diversity within a medically important cell lineage.

2.
Neuron ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38729150

RESUMO

To investigate which activity patterns in sensory cortex are relevant for perceptual decision-making, we combined two-photon calcium imaging and targeted two-photon optogenetics to interrogate barrel cortex activity during perceptual discrimination. We trained mice to discriminate bilateral whisker deflections and report decisions by licking left or right. Two-photon calcium imaging revealed sparse coding of contralateral and ipsilateral whisker input in layer 2/3, with most neurons remaining silent during the task. Activating pyramidal neurons using two-photon holographic photostimulation evoked a perceptual bias that scaled with the number of neurons photostimulated. This effect was dominated by optogenetic activation of non-coding neurons, which did not show sensory or motor-related activity during task performance. Photostimulation also revealed potent recruitment of cortical inhibition during sensory processing, which strongly and preferentially suppressed non-coding neurons. Our results suggest that a pool of non-coding neurons, selectively suppressed by network inhibition during sensory processing, can be recruited to enhance perception.

3.
Nature ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720074

RESUMO

Phosphoinositide-3-kinase-γ (PI3Kγ) is implicated as a target to repolarize tumour-associated macrophages and promote antitumour immune responses in solid cancers1-4. However, cancer cell-intrinsic roles of PI3Kγ are unclear. Here, by integrating unbiased genome-wide CRISPR interference screening with functional analyses across acute leukaemias, we define a selective dependency on the PI3Kγ complex in a high-risk subset that includes myeloid, lymphoid and dendritic lineages. This dependency is characterized by innate inflammatory signalling and activation of phosphoinositide 3-kinase regulatory subunit 5 (PIK3R5), which encodes a regulatory subunit of PI3Kγ5 and stabilizes the active enzymatic complex. We identify p21 (RAC1)-activated kinase 1 (PAK1) as a noncanonical substrate of PI3Kγ that mediates this cell-intrinsic dependency and find that dephosphorylation of PAK1 by PI3Kγ inhibition impairs mitochondrial oxidative phosphorylation. Treatment with the selective PI3Kγ inhibitor eganelisib is effective in leukaemias with activated PIK3R5. In addition, the combination of eganelisib and cytarabine prolongs survival over either agent alone, even in patient-derived leukaemia xenografts with low baseline PIK3R5 expression, as residual leukaemia cells after cytarabine treatment have elevated G protein-coupled purinergic receptor activity and PAK1 phosphorylation. Together, our study reveals a targetable dependency on PI3Kγ-PAK1 signalling that is amenable to near-term evaluation in patients with acute leukaemia.

4.
Proc Natl Acad Sci U S A ; 121(20): e2322688121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38709925

RESUMO

Brain metastatic breast cancer is particularly lethal largely due to therapeutic resistance. Almost half of the patients with metastatic HER2-positive breast cancer develop brain metastases, representing a major clinical challenge. We previously described that cancer-associated fibroblasts are an important source of resistance in primary tumors. Here, we report that breast cancer brain metastasis stromal cell interactions in 3D cocultures induce therapeutic resistance to HER2-targeting agents, particularly to the small molecule inhibitor of HER2/EGFR neratinib. We investigated the underlying mechanisms using a synthetic Notch reporter system enabling the sorting of cancer cells that directly interact with stromal cells. We identified mucins and bulky glycoprotein synthesis as top-up-regulated genes and pathways by comparing the gene expression and chromatin profiles of stroma-contact and no-contact cancer cells before and after neratinib treatment. Glycoprotein gene signatures were also enriched in human brain metastases compared to primary tumors. We confirmed increased glycocalyx surrounding cocultures by immunofluorescence and showed that mucinase treatment increased sensitivity to neratinib by enabling a more efficient inhibition of EGFR/HER2 signaling in cancer cells. Overexpression of truncated MUC1 lacking the intracellular domain as a model of increased glycocalyx-induced resistance to neratinib both in cell culture and in experimental brain metastases in immunodeficient mice. Our results highlight the importance of glycoproteins as a resistance mechanism to HER2-targeting therapies in breast cancer brain metastases.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Glicocálix , Quinolinas , Receptor ErbB-2 , Células Estromais , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Feminino , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-2/genética , Glicocálix/metabolismo , Animais , Linhagem Celular Tumoral , Células Estromais/metabolismo , Células Estromais/patologia , Quinolinas/farmacologia , Camundongos , Comunicação Celular , Técnicas de Cocultura , Mucina-1/metabolismo , Mucina-1/genética , Transdução de Sinais , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inibidores
5.
Ophthalmologica ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38723611

RESUMO

INTRODUCTION: This study aimed to investigate the incidence of and risk factors for epiretinal membrane (ERM) formation following primary rhegmatogenous retinal detachment (RRD) repair. METHODS: This comparative, retrospective, single center cohort study included eyes with primary RRD treated between 2011 and 2023 at Massachusetts Eye and Ear, Boston, Massachusetts, with pars plana vitrectomy (PPV), scleral buckle (SB), PPV+SB, or pneumatic retinopexy (PnR). Demographic, clinical, and surgical parameters were collected from medical records. The primary outcome was the risk of ERM formation, while the secondary outcome was the risk of ERM requiring surgery. Univariable and multivariable Cox regression was performed, and a hazard ratio (HR) and 95% confidence interval (95%CI) were reported. RESULTS: Overall, 394 eyes were included. The mean age was 58.49±12.8 years and most patients were male. There was a significantly lower risk of ERM formation following SB compared to PPV in the univariable analysis (HR=0.22, 95%CI=0.08-0.60, p=0.003); however, there was no significant association between treatment modality and ERM formation on multivariable Cox regression controlling for confounding factors (p=0.24). ERM formation was found more commonly in patients who were older (HR=1.03 per 1 year increase in age, 95%CI=1.01-1.04, p=0.001), those with worse baseline visual acuity (HR=1.36, 95%CI=1.09-1.71, p=0.008), and those with macula-off RRDs (HR=2.16, 95%CI=1.41-3.32, p<0.001). CONCLUSION: Surgical modality does not have a significant impact on the risk of ERM following retinal detachment repair. However, age, baseline visual acuity, and macular status are important predictors of ERM formation after RRD repair.

6.
Phys Rev Lett ; 132(16): 162501, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38701469

RESUMO

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6

7.
Eur J Cancer ; 204: 114074, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38691877

RESUMO

Cancers of the skin are the most commonly occurring cancers in humans. In fair-skinned populations, up to 95% of keratinocyte skin cancers and 70-95% of cutaneous melanomas are caused by ultraviolet radiation and are thus theoretically preventable. Currently, however, there is no comprehensive global advice on practical steps to be taken to reduce the toll of skin cancer. To address this gap, an expert working group comprising clinicians and researchers from Africa, America, Asia, Australia, and Europe, together with learned societies (European Association of Dermato-Oncology, Euromelanoma, Euroskin, European Union of Medical Specialists, and the Melanoma World Society) reviewed the extant evidence and issued the following evidence-based recommendations for photoprotection as a strategy to prevent skin cancer. Fair skinned people, especially children, should minimise their exposure to ultraviolet radiation, and are advised to use protective measures when the UV index is forecast to reach 3 or higher. Protective measures include a combination of seeking shade, physical protection (e.g. clothing, hat, sunglasses), and applying broad-spectrum, SPF 30 + sunscreens to uncovered skin. Intentional exposure to solar ultraviolet radiation for the purpose of sunbathing and tanning is considered an unhealthy behaviour and should be avoided. Similarly, use of solaria and other artificial sources of ultraviolet radiation to encourage tanning should be strongly discouraged, through regulation if necessary. Primary prevention of skin cancer has a positive return on investment. We encourage policymakers to communicate these messages to the general public and promote their wider implementation.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38738687

RESUMO

BACKGROUND: As exposure to UV radiation is the primary modifiable environmental risk factor associated with skin cancer, it remains the principal focus of most prevention strategies. Numerous sun protection campaigns have been implemented worldwide; however, their impact on the actual incidence and mortality rates of skin cancer seems to be limited. To create successful skin cancer prevention campaigns, it is important to have a comprehensive understanding of individuals' attitudes and behaviours regarding sun protection. The aim of the current study was to determine and report on the prevalence of self-reported attitudes, knowledge and behaviours regarding two of the major sun protection recommendations-avoidance of sun exposure and use of sunscreens-in an international representative sample across five continents. METHODS: This cross-sectional study was conducted in 20 countries using a web-based online survey. FINDINGS: A total of 50,552 individuals, comprising 25,388 men (50.22%) and 25,164 women (49.78%), participated in the survey. Among them, 83.2% reported having been voluntarily exposed to the sun (for sun-basking reasons) at least once in the last 12 months, and 47.96% acknowledged being exposed to the sun between the hours of 10 AM and 4 PM. The primary reason for non-adherence was that these hours were the most convenient times (32.28%). Only 24.05% reported applying sunscreen every 2 h when outdoors. Forgetfulness was the primary reason as provided by 27.79% of participants. Males and older age groups were less likely to adopt sun-protective behaviours around the world. Forgetfulness and the challenges posed by time constraints seem to be the biggest barriers to proper adherence. INTERPRETATION: These findings should prompt the collaboration with health authorities and the manufacturers to enhance adherence by setting reasonable sunscreen prices and creating formulations that make their application less burdensome.

9.
Clin Cancer Res ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652676

RESUMO

Expansion of cDC cells via FLT3 agonism has promising therapeutic potential in the treatment of advanced solid tumors. Here, we discuss the results of a clinical trial using GS-3583, an FLT3 agonist, that was stopped after a patient in the study developed acute myeloid leukemia.

12.
J Neurosurg Case Lessons ; 7(16)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621308

RESUMO

BACKGROUND: Primary hemifacial spasm (HFS) is usually caused by arterial compression of the facial nerve at the root exit zone at the brainstem. Rarely, a purely venous compression is seen. However, arachnoid bands strangulating the facial nerve have not been recognized as a cause of hemifacial spasm. OBSERVATIONS: The authors present a case of a 24-year-old female who had experienced HFS for 9 years. Endoscopic inspection of the root exit zone revealed no vascular compression but an arachnoid band strangulating the facial nerve. After cutting the band, the lateral spread response disappeared, and the patient was immediately spasm free after the surgery. Two years later, she was still doing well without any spasms. LESSONS: This is the third patient in the authors' series of 535 patients who had no vascular conflict but rather a strangulation of the nerve by arachnoid bands. All patients have remained spasm free. To the authors' knowledge, no other group has reported arachnoid bands as an etiological factor of HFS so far.

13.
Photodermatol Photoimmunol Photomed ; 40(3): e12967, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38616500

RESUMO

BACKGROUND/PURPOSE: Nowadays, there are emerging trends in customized and personalized photoprotection, focusing on the innovative approaches to enhance sun protection efficacy tailored to individual needs. METHODS: We conducted an electronic search of the following databases: MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Skin Group Specialised Skin Register, and TESEO. Specific search terms related to personalized photoprotection and the variables of age, genetic predisposition, skin phototype, photodermatosis, and physiological conditions such as pregnancy, as well as lifestyle habits were used. RESULTS/CONCLUSION: The article highlights the challenges and opportunities in adopting personalized photoprotection strategies, aiming to promote skin health and prevent the harmful effects of UV radiation in the era of precision medicine.


Assuntos
Predisposição Genética para Doença , Protetores Solares , Feminino , Gravidez , Humanos , Protetores Solares/uso terapêutico , Revisões Sistemáticas como Assunto , Hábitos , Estilo de Vida
14.
J Neurosci ; 44(16)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38499360

RESUMO

Social experiences carry tremendous weight in our decision-making, even when social partners are not present. To determine mechanisms, we trained female mice to respond for two food reinforcers. Then, one food was paired with a novel conspecific. Mice later favored the conspecific-associated food, even in the absence of the conspecific. Chemogenetically silencing projections from the prelimbic subregion (PL) of the medial prefrontal cortex to the basolateral amygdala (BLA) obstructed this preference while leaving social discrimination intact, indicating that these projections are necessary for socially driven choice. Further, mice that performed the task had greater densities of dendritic spines on excitatory BLA neurons relative to mice that did not. We next induced chemogenetic receptors in cells active during social interactions-when mice were encoding information that impacted later behavior. BLA neurons stimulated by social experience were necessary for mice to later favor rewards associated with social conspecifics but not make other choices. This profile contrasted with that of PL neurons stimulated by social experience, which were necessary for choice behavior in social and nonsocial contexts alike. The PL may convey a generalized signal allowing mice to favor particular rewards, while units in the BLA process more specialized information, together supporting choice motivated by social information.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Córtex Pré-Frontal , Feminino , Camundongos , Animais , Córtex Pré-Frontal/fisiologia , Tonsila do Cerebelo/fisiologia , Neurônios/fisiologia , Complexo Nuclear Basolateral da Amígdala/fisiologia
15.
Nat Commun ; 15(1): 2456, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503769

RESUMO

The mechanistic link between neural circuit activity and behavior remains unclear. While manipulating cortical activity can bias certain behaviors and elicit artificial percepts, some tasks can still be solved when cortex is silenced or removed. Here, mice were trained to perform a visual detection task during which we selectively targeted groups of visually responsive and co-tuned neurons in L2/3 of primary visual cortex (V1) for two-photon photostimulation. The influence of photostimulation was conditional on two key factors: the behavioral state of the animal and the contrast of the visual stimulus. The detection of low-contrast stimuli was enhanced by photostimulation, while the detection of high-contrast stimuli was suppressed, but crucially, only when mice were highly engaged in the task. When mice were less engaged, our manipulations of cortical activity had no effect on behavior. The behavioral changes were linked to specific changes in neuronal activity. The responses of non-photostimulated neurons in the local network were also conditional on two factors: their functional similarity to the photostimulated neurons and the contrast of the visual stimulus. Functionally similar neurons were increasingly suppressed by photostimulation with increasing visual stimulus contrast, correlating with the change in behavior. Our results show that the influence of cortical activity on perception is not fixed, but dynamically and contextually modulated by behavioral state, ongoing activity and the routing of information through specific circuits.


Assuntos
Córtex Visual , Animais , Camundongos , Estimulação Luminosa/métodos , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Neurônios/fisiologia
18.
Cancer Med ; 13(6): e7124, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38529687

RESUMO

INTRODUCTION: Increased moderate to vigorous physical activity (MVPA) can improve clinical and psychosocial outcomes for people living with and beyond cancer (LWBC). This study aimed to assess the feasibility and acceptability of trial procedures in a pilot randomised controlled trial (RCT) of a theory-driven app-based intervention with behavioural support focused on promoting brisk walking (a form of MVPA) in people LWBC (APPROACH). METHODS: Participants diagnosed with breast, prostate or colorectal cancer were recruited from a single UK hospital site. Assessments at baseline and 3 months included online questionnaires, device-measured brisk walking (activPAL accelerometer) and self-reported weight and height. Participants were randomised to intervention or control (care as usual). The intervention comprised a non-cancer-specific app to promote brisk walking (National Health Service 'Active 10') augmented with print information about habit formation, a walking planner and two behavioural support telephone calls. Feasibility and acceptability of trial procedures were explored. Initial estimates for physical activity informed a power calculation for a phase III RCT. A preliminary health economics analysis was conducted. RESULTS: Of those medically eligible, 369/577 (64%) were willing to answer further eligibility questions and 90/148 (61%) of those eligible were enrolled. Feasibility outcomes, including retention (97%), assessment completion rates (>86%) and app download rates in the intervention group (96%), suggest that the trial procedures are acceptable and that the intervention is feasible. The phase III RCT will require 472 participants to be randomised. As expected, the preliminary health economic analyses indicate a high level of uncertainty around the cost-effectiveness of the intervention. CONCLUSIONS: This pilot study demonstrates that a large trial of the brisk walking intervention with behavioural support is both feasible and acceptable to people LWBC. The results support progression onto a confirmatory phase III trial to determine the efficacy and cost-effectiveness of the intervention.


Assuntos
Neoplasias Colorretais , Aplicativos Móveis , Masculino , Humanos , Próstata , Estudos de Viabilidade , Caminhada , Reino Unido , Neoplasias Colorretais/terapia
19.
Neurosurgery ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456708

RESUMO

BACKGROUND AND OBJECTIVES: Despite a 90% success rate, microvascular decompression occasionally fails to resolve hemifacial spasm (HFS), necessitating revision surgery. We investigated recurrent cases to identify underlying causes. METHODS: We evaluated patients at our institution who underwent revision microvascular decompression because of recurrent or persistent HFS, assessing recurrence causes, decompression techniques, complications, and outcomes. Data considered included demographics, preoperative symptoms, disease duration, offending vessel, and magnetic resonance findings. Surgical notes and intraoperative videos were reviewed, and telephone interviews were conducted for recent outcomes. RESULTS: Out of our ongoing series of 493 patients, 43 patients (8.7%) required revision surgery with a patient cohort of 33 females and 10 males. The average symptom duration was 10 years. The median time between primary and revision surgery was 14 months. Thirteen patients (30.2%) underwent initial surgery elsewhere. Adhesions of Teflon pledgets to the facial nerve were the primary cause of nonresolution in 23 patients (53.5%), while in 13 (30.2%), a missed vascular compression was identified. Sixteen patients (37.2%) had sufficient decompression by removing the conflicting pledgets. During 10 revisions (23.3%), additional Teflon pledgets were necessary. After a median follow-up of 67 months after revision surgery, 27 patients (62.8%) reported complete spasm resolution. Six patients (14.0%) had a good outcome with over 90% reduction of their spasms, 3 patients (7.0%) stated a fair outcome (50% improvement), while 7 patients (16.3%) had no improvement. CONCLUSION: According to our results, adhesions of Teflon to the facial nerve may cause HFS recurrence. Therefore, whenever possible, Teflon should be placed without nerve contact between the brainstem and the offending vessel. Using a sling or bridge technique seems to be beneficial because it leaves the facial nerve completely free. Persistent symptoms often result from missed offending vessels in the pontomedullary sulcus indicating the benefit of endoscopic inspection of this area with an endoscope.

20.
Front Oncol ; 14: 1344798, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38434681

RESUMO

Background: Portal vein tumor thrombus (PVTT) is a common complication and an obstacle to treatment, with a high recurrence rate and poor prognosis. There is still no global consensus or standard guidelines on the management of hepatocellular carcinoma (HCC) with PVTT. Increasing evidence suggests that more aggressive treatment modalities, including transarterial chemoembolization, radiotherapy, targeted therapy, and various combination therapies, may improve the prognosis and prolong the survival of advanced hepatocellular carcinoma (aHCC) patients with PVTT. We aim to comprehensively review and compare the efficacy and safety of these advanced options for aHCC with PVTT. Methods: A comprehensive literature search was conducted on PubMed and EMBASE for phase II or III randomized controlled trials (RCTs) investigating multimodality treatments for aHCC with PVTT. Kaplan-Meier curves for overall survival (OS) and progression-free survival were constructed to retrieve individual patient-level data to strengthen the comparison of the benefits of all multimodality treatments of interest. Each study was pooled in a fixed-effects network meta-analysis (NMA). We also conducted subgroup analyses using risk ratios extracted from each study, including viral etiology, Barcelona Clinic Liver Cancer (BCLC) staging, alpha-fetoprotein (AFP) levels, macrovascular invasion or portal vein tumor thrombosis, and extrahepatic spread. Multimodality treatments were ranked using SUCRA scores. Results: We identified 15 randomized controlled trials with 16 multimodality regimens that met the inclusion criteria. Among them, 5,236 patients with OS results and 5,160 patients with PFS results were included in the analysis. The hepatic arterial infusion chemotherapy of fluorouracil, leucovorin, and oxaliplatin (HAIC-FO) showed OS and PFS benefits over all the other therapies. In terms of OS, HAIC-FO, nivolumab, and TACE+Len were superior to sorafenib, lenvatinib, and donatinib monotherapies, as well as HAIC-FO+Sor. In terms of PFS, TACE+Len showed better benefits than lenvatinib, donatinib, and tremelimumab+durvalumab. A low heterogeneity (I 2 < 50%) and consistency were observed. The SUCRA score for OS ranked HAIC-FO+sorafenib as the best treatment option among all multimodality treatments in hepatitis B, MVI, or PVTT with EHS and AFP 400 µg/L subgroups. Conclusion: HAIC-FO and HAIC-FO+sorafenib are statistically better options for unresectable hepatocellular carcinoma with PVTT among the multimodality treatments, and their effective and safe implementation may provide the best outcomes for HCC-PVTT patients.

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