35 research outputs found
MAPK pathway control of stem cell proliferation and differentiation in the embryonic pituitary provides insights into the pathogenesis of papillary craniopharyngioma
Despite the importance of the RAS-RAF-MAPK pathway in normal physiology and disease of numerous organs, its role during pituitary development and tumourigenesis remains largely unknown. Here we show that the over-activation of the MAPK pathway, through conditional expression of the gain-of-function alleles BrafV600E and KrasG12D in the developing mouse pituitary, results in severe hyperplasia and abnormal morphogenesis of the gland by the end of gestation. Cell-lineage commitment and terminal differentiation are disrupted, leading to a significant reduction in numbers of most of the hormone-producing cells before birth, with the exception of corticotrophs. Of note, Sox2+ve stem cells and clonogenic potential are drastically increased in the mutant pituitaries. Finally, we reveal that papillary craniopharyngioma (PCP), a benign human pituitary tumour harbouring BRAF p.V600E also contains Sox2+ve cells with sustained proliferative capacity and disrupted pituitary differentiation. Together, our data demonstrate a critical function of the MAPK pathway in controlling the balance between proliferation and differentiation of Sox2+ve cells and suggest that persistent proliferative capacity of Sox2+ve cells may underlie the pathogenesis of PCP.</p
Safety, immunogenicity, and reactogenicity of BNT162b2 and mRNA-1273 COVID-19 vaccines given as fourth-dose boosters following two doses of ChAdOx1 nCoV-19 or BNT162b2 and a third dose of BNT162b2 (COV-BOOST): a multicentre, blinded, phase 2, randomised trial
Functional diversity and co-operativity between subclonal populations of paediatric glioblastoma and diffuse intrinsic pontine glioma cells
The failure to develop effective therapies for pediatric glioblastoma (pGBM) and diffuse intrinsic pontine glioma (DIPG) is in part due to their intrinsic heterogeneity. We aimed to quantitatively assess the extent to which this was present in these tumors through subclonal genomic analyses and to determine whether distinct tumor subpopulations may interact to promote tumorigenesis by generating subclonal patient-derived models in vitro and in vivo. Analysis of 142 sequenced tumors revealed multiple tumor subclones, spatially and temporally coexisting in a stable manner as observed by multiple sampling strategies. We isolated genotypically and phenotypically distinct subpopulations that we propose cooperate to enhance tumorigenicity and resistance to therapy. Inactivating mutations in the H4K20 histone methyltransferase KMT5B (SUV420H1), present in <1% of cells, abrogate DNA repair and confer increased invasion and migration on neighboring cells, in vitro and in vivo, through chemokine signaling and modulation of integrins. These data indicate that even rare tumor subpopulations may exert profound effects on tumorigenesis as a whole and may represent a new avenue for therapeutic development. Unraveling the mechanisms of subclonal diversity and communication in pGBM and DIPG will be an important step toward overcoming barriers to effective treatments
Safety, immunogenicity, and reactogenicity of BNT162b2 and mRNA-1273 COVID-19 vaccines given as fourth-dose boosters following two doses of ChAdOx1 nCoV-19 or BNT162b2 and a third dose of BNT162b2 (COV-BOOST): a multicentre, blinded, phase 2, randomised trial
Background Some high-income countries have deployed fourth doses of COVID-19 vaccines, but the clinical need, effectiveness, timing, and dose of a fourth dose remain uncertain. We aimed to investigate the safety, reactogenicity, and immunogenicity of fourth-dose boosters against COVID-19.Methods The COV-BOOST trial is a multicentre, blinded, phase 2, randomised controlled trial of seven COVID-19 vaccines given as third-dose boosters at 18 sites in the UK. This sub-study enrolled participants who had received BNT162b2 (Pfizer-BioNTech) as their third dose in COV-BOOST and randomly assigned them (1:1) to receive a fourth dose of either BNT162b2 (30 µg in 0·30 mL; full dose) or mRNA-1273 (Moderna; 50 µg in 0·25 mL; half dose) via intramuscular injection into the upper arm. The computer-generated randomisation list was created by the study statisticians with random block sizes of two or four. Participants and all study staff not delivering the vaccines were masked to treatment allocation. The coprimary outcomes were safety and reactogenicity, and immunogenicity (antispike protein IgG titres by ELISA and cellular immune response by ELISpot). We compared immunogenicity at 28 days after the third dose versus 14 days after the fourth dose and at day 0 versus day 14 relative to the fourth dose. Safety and reactogenicity were assessed in the per-protocol population, which comprised all participants who received a fourth-dose booster regardless of their SARS-CoV-2 serostatus. Immunogenicity was primarily analysed in a modified intention-to-treat population comprising seronegative participants who had received a fourth-dose booster and had available endpoint data. This trial is registered with ISRCTN, 73765130, and is ongoing.Findings Between Jan 11 and Jan 25, 2022, 166 participants were screened, randomly assigned, and received either full-dose BNT162b2 (n=83) or half-dose mRNA-1273 (n=83) as a fourth dose. The median age of these participants was 70·1 years (IQR 51·6–77·5) and 86 (52%) of 166 participants were female and 80 (48%) were male. The median interval between the third and fourth doses was 208·5 days (IQR 203·3–214·8). Pain was the most common local solicited adverse event and fatigue was the most common systemic solicited adverse event after BNT162b2 or mRNA-1273 booster doses. None of three serious adverse events reported after a fourth dose with BNT162b2 were related to the study vaccine. In the BNT162b2 group, geometric mean anti-spike protein IgG concentration at day 28 after the third dose was 23 325 ELISA laboratory units (ELU)/mL (95% CI 20 030–27 162), which increased to 37 460 ELU/mL (31 996–43 857) at day 14 after the fourth dose, representing a significant fold change (geometric mean 1·59, 95% CI 1·41–1·78). There was a significant increase in geometric mean anti-spike protein IgG concentration from 28 days after the third dose (25 317 ELU/mL, 95% CI 20 996–30 528) to 14 days after a fourth dose of mRNA-1273 (54 936 ELU/mL, 46 826–64 452), with a geometric mean fold change of 2·19 (1·90–2·52). The fold changes in anti-spike protein IgG titres from before (day 0) to after (day 14) the fourth dose were 12·19 (95% CI 10·37–14·32) and 15·90 (12·92–19·58) in the BNT162b2 and mRNA-1273 groups, respectively. T-cell responses were also boosted after the fourth dose (eg, the fold changes for the wild-type variant from before to after the fourth dose were 7·32 [95% CI 3·24–16·54] in the BNT162b2 group and 6·22 [3·90–9·92] in the mRNA-1273 group).Interpretation Fourth-dose COVID-19 mRNA booster vaccines are well tolerated and boost cellular and humoral immunity. Peak responses after the fourth dose were similar to, and possibly better than, peak responses after the third dose
Bridging pre-surgical endocrine therapy for breast cancer during the COVID-19 pandemic: outcomes from the B-MaP-C study
Purpose:
The B-MaP-C study investigated changes to breast cancer care that were necessitated by the COVID-19 pandemic. Here we present a follow-up analysis of those patients commenced on bridging endocrine therapy (BrET), whilst they were awaiting surgery due to reprioritisation of resources.
Methods:
This multicentre, multinational cohort study recruited 6045 patients from the UK, Spain and Portugal during the peak pandemic period (Feb–July 2020). Patients on BrET were followed up to investigate the duration of, and response to, BrET. This included changes in tumour size to reflect downstaging potential, and changes in cellular proliferation (Ki67), as a marker of prognosis.
Results:
1094 patients were prescribed BrET, over a median period of 53 days (IQR 32–81 days). The majority of patients (95.6%) had strong ER expression (Allred score 7–8/8). Very few patients required expedited surgery, due to lack of response (1.2%) or due to lack of tolerance/compliance (0.8%). There were small reductions in median tumour size after 3 months’ treatment duration; median of 4 mm [IQR − 20, 4]. In a small subset of patients ( n = 47), a drop in cellular proliferation (Ki67) occurred in 26 patients (55%), from high (Ki67 ≥ 10%) to low (< 10%), with at least one month’s duration of BrET.
Discussion:
This study describes real-world usage of pre-operative endocrine therapy as necessitated by the pandemic. BrET was found to be tolerable and safe. The data support short-term (≤ 3 months) usage of pre-operative endocrine therapy. Longer-term use should be investigated in future trials
Dislipidemia and oxidative stress in mild and in severe psoriasis as a risk for cardiovascular disease
Psoriasis is a common chronic and recurrent inflammatory skin disorder that has been associated with oxidative stress, abnormal plasma lipid metabolism and with high frequency of cardiovascular events. This prevalence seems to be related to the severity of psoriasis, as it occurs more frequently in patients presenting large areas of the body affected with psoriasis lesions. The aim of our work was to evaluate the development of oxidative stress and of dislipidemia in psoriasis, and to look for a correlation between their levels and worsening of psoriasis. We evaluated lipid profile, total antioxidant capacity, antioxidant vitamins A and E, and lipoperoxidation products. The study was performed in controls and in patients presenting mild and severe psoriasis. Patients presented risk changes in lipid profile (a rise in cholesterol (P<0.01), triglycerides (P<0.001), low density lipoprotein cholesterol (P<0.01), very low density lipoprotein cholesterol (P<0.01), apolipoprotein B (P<0.001) and lipoprotein(a) (P<0.001); and a reduction in high density lipoprotein cholesterol (P<0.001)), a rise in lipoperoxidation products (P<0.001) and a reduction in total antioxidant capacity (P<0.001) and in antioxidant vitamins A (P<0.001) and E (P<0.05). Moreover, we found that the worsening of psoriasis was associated with the enhancement of oxidative stress and of the lipid risk changes. Our data suggest that psoriasis patients must be considered as a group at risk for cardiovascular disease and that this risk seems to be higher in severe psoriasis. In addition, a possible benefit of an enriched diet or of a supplement of vitamins A and E in psoriasis patients should be further studied.http://www.sciencedirect.com/science/article/B6T57-4239801-4/1/5dce64d938dedc90c152b16534adbff
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Dogs' responses to remote interactions with humans: an exploratory analysis
Pet owners are increasingly using devices to monitor and communicate with their pet dogs remotely. These technologies are developed in an effort to address separation anxiety, boredom, and safety concerns of dogs left alone in the home. However, it is unclear how dogs respond to each of the interaction modalities featured in these devices, and also whether dogs perceive such interactions as an interaction with their owner. This work provides an initial exploration of dogs' experiences when exposed to the individual stimuli frequently used in such devices. Preliminary results, focusing on five common distress behaviours, demonstrated an increase in distress behaviours in all trials containing a stimulus when compared to a control with no stimuli. These results offer an initial insight into dogs' responses to remote-interaction devices and provide potential implications for the design and advised usage of any remote pet-monitoring devices that incorporate these functionalities.</p
