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1.
Cell ; 186(13): 2911-2928.e20, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37269832

RESUMO

Animals with complex nervous systems demand sleep for memory consolidation and synaptic remodeling. Here, we show that, although the Caenorhabditis elegans nervous system has a limited number of neurons, sleep is necessary for both processes. In addition, it is unclear if, in any system, sleep collaborates with experience to alter synapses between specific neurons and whether this ultimately affects behavior. C. elegans neurons have defined connections and well-described contributions to behavior. We show that spaced odor-training and post-training sleep induce long-term memory. Memory consolidation, but not acquisition, requires a pair of interneurons, the AIYs, which play a role in odor-seeking behavior. In worms that consolidate memory, both sleep and odor conditioning are required to diminish inhibitory synaptic connections between the AWC chemosensory neurons and the AIYs. Thus, we demonstrate in a living organism that sleep is required for events immediately after training that drive memory consolidation and alter synaptic structures.


Assuntos
Caenorhabditis elegans , Odorantes , Animais , Caenorhabditis elegans/fisiologia , Olfato , Sono/fisiologia , Sinapses/fisiologia
2.
Emerg Med Australas ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39021286

RESUMO

OBJECTIVE: To profile the initial 6-month experience at the Victorian Heart Hospital (VHH) cardiac emergency (CE). The primary objective was to describe VHH CE patient characteristics, including presenting complaint, final diagnosis and disposition. Secondary objectives were to report on patient numbers, patient source and quality indicator performance including ambulance off-load by 40 min, waiting time and length of stay (LOS). METHODS: A retrospective review included all patients who presented to the VHH CE from 9 March 2023 to 8 September 2023. Patient reports containing the relevant clinical information were generated from the CE electronic medical record system. Diagnoses of MI were checked for accuracy by full record review. RESULTS: There were 3303 CE presentations in the first 6 months of operation, of which 6% were transferred from other sites. Median age was 65 years (interquartile range [IQR]: 53-77), 56% were males; the most common presenting complaints were presumed cardiac chest pain (67%) and arrhythmia (17%). The admission, discharge and transfer rates were 38%, 54% and 8%, respectively. In total, 15% were diagnosed with MI. The most common diagnoses for discharged and admitted patients were non-specific chest pain (57%) and ST-elevation MI (22%), respectively. Ambulance off-load by 40 min was met for 96%. Median waiting time was 6 min (IQR: 3-10). Median CE LOS for discharged and admitted patients was 3.2 h (IQR: 2.5-4.0) and 3.7 h (IQR: 1.8-6.0), with 75% and 56% being <4 h, respectively. CONCLUSIONS: The population predominantly had cardiovascular disease as expected. Some performance indicators, including ED LOS, were identified as requiring intervention.

3.
Cancers (Basel) ; 15(12)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37370789

RESUMO

Breast cancer alone accounts for the majority of cancer deaths among women, with the most commonly diagnosed subtype being estrogen receptor positive (ER+). Survival has greatly improved for patients with ER+ breast cancer, due in part to the development of antiestrogen compounds, such as tamoxifen. While treatment of the primary disease is often successful, as many as 30% of patients will experience recurrence and metastasis, mainly due to developed endocrine therapy resistance. In this study, we discovered two tamoxifen combination therapies, with simeprevir and VX-680, that reduce the tumor burden in animal models of ER+ breast cancer more than either compound or tamoxifen alone. Additionally, these tamoxifen combinations reduced the expression of HER2, a hallmark of tamoxifen treatment, which can facilitate acquisition of a treatment-resistant phenotype. These combinations could provide clinical benefit by potentiating tamoxifen treatment in ER+ breast cancer.

4.
Sci Rep ; 12(1): 21248, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482068

RESUMO

The goals of this study were to identify transcriptomic changes that arise in basal-like breast cancer cells during the development of resistance to epidermal growth factor receptor inhibitors (EGFRi) and to identify drugs that are cytotoxic once EGFRi resistance occurs. Human patient-derived xenografts (PDXs) were grown in immunodeficient mice and treated with a set of EGFRi; the EGFRi erlotinib was selected for more expansive in vivo studies. Single-cell RNA sequencing was performed on mammary tumors from the basal-like PDX WHIM2 that was treated with vehicle or erlotinib for 9 weeks. The PDX was then subjected to long-term erlotinib treatment in vivo. Through serial passaging, an erlotinib-resistant subline of WHIM2 was generated. Bulk RNA-sequencing was performed on parental and erlotinib-resistant tumors. In vitro high-throughput drug screening with > 500 clinically used compounds was performed on parental and erlotinib-resistant cells. Previously published bulk gene expression microarray data from MMTV-Wnt1 tumors were contrasted with the WHIM2 PDX data. Erlotinib effectively inhibited WHIM2 tumor growth for approximately 4 weeks. Compared to untreated cells, single-cell RNA sequencing revealed that a greater proportion of erlotinib-treated cells were in the G1 phase of the cell cycle. Comparison of WHIM2 and MMTV-Wnt1 gene expression data revealed a set of 38 overlapping genes that were differentially expressed in the erlotinib-resistant WHIM2 and MMTV-Wnt1 tumors. Comparison of all three data types revealed five genes that were upregulated across all erlotinib-resistant samples: IL19, KLK7, LCN2, SAA1, and SAA2. Of these five genes, LCN2 was most abundantly expressed in triple-negative breast cancers, and its knockdown restored erlotinib sensitivity in vitro. Despite transcriptomic differences, parental and erlotinib-resistant WHIM2 displayed similar responses to the majority of drugs assessed for cytotoxicity in vitro. This study identified transcriptomic changes arising in erlotinib-resistant basal-like breast cancer. These data could be used to identify a biomarker or develop a gene signature predictive of patient response to EGFRi. Future studies should explore the predictive capacity of these gene signatures as well as how LCN2 contributes to the development of EGFRi resistance.


Assuntos
Neoplasias da Mama , Receptores ErbB , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , Ensaios de Triagem em Larga Escala , Resistencia a Medicamentos Antineoplásicos
5.
Ann Gastroenterol ; 33(3): 293-298, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32382233

RESUMO

BACKGROUND: Studies investigating the association between direct-acting antivirals (DAAs) and the recurrence of hepatocellular carcinoma (HCC) related to hepatitis C (HCV) have yielded conflicting results. The objective of this meta-analysis was to define the short- and long-term recurrence rates of HCC after DAA treatment. METHODS: A search of multiple databases was performed, including Scopus, Cochrane, MEDLINE/PubMed and abstracts from gastroenterology meetings. Only studies reporting the recurrence of HCC in patients receiving DAA treatment, compared to HCV controls without DAA treatment, were evaluated. A meta-analysis was completed using the Mantel-Haenszel model. RESULTS: A comprehensive literature search resulted in 32 abstracts and papers. Six papers met our inclusion criteria and were included in the analysis. Follow up ranged from 1.25-4 years. Analysis of these 6 studies found a >60% lower risk of HCC recurrence in patients exposed to DAA compared to controls (odds ratio [OR] 0.36, 95% confidence interval [CI] 0.27-0.47; P<0.001; I 2=88%). A sensitivity analysis, which excluded studies showing the lowest recurrence rate to reduce heterogeneity, showed that patients receiving DAA still had a 60% lower risk of developing HCC (OR 0.4, 95%CI 0.26-0.61; P<0.0001; I 2=39%) and a 66% lower risk of developing HCC beyond 1 year (OR 0.34, 95%CI 0.22-0.54; P<0.00001; I 2=0%) compared to controls. CONCLUSIONS: The use of DAA is associated with a significantly lower risk of HCC development compared to DAA-untreated patients, both overall and beyond 1 year of treatment. Further studies are needed to assess the impact of DAAs on early recurrence.

6.
Elife ; 62017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28873053

RESUMO

Predators and prey co-evolve, each maximizing their own fitness, but the effects of predator-prey interactions on cellular and molecular machinery are poorly understood. Here, we study this process using the predator Caenorhabditis elegans and the bacterial prey Streptomyces, which have evolved a powerful defense: the production of nematicides. We demonstrate that upon exposure to Streptomyces at their head or tail, nematodes display an escape response that is mediated by bacterially produced cues. Avoidance requires a predicted G-protein-coupled receptor, SRB-6, which is expressed in five types of amphid and phasmid chemosensory neurons. We establish that species of Streptomyces secrete dodecanoic acid, which is sensed by SRB-6. This behavioral adaptation represents an important strategy for the nematode, which utilizes specialized sensory organs and a chemoreceptor that is tuned to recognize the bacteria. These findings provide a window into the molecules and organs used in the coevolutionary arms race between predator and potential prey.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Células Quimiorreceptoras/fisiologia , Neurônios/fisiologia , Streptomyces/patogenicidade , Adaptação Fisiológica , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/microbiologia , Quimiotaxia , Neurônios/citologia , Neurônios/microbiologia , Filogenia , Transdução de Sinais
7.
BMC Bioinformatics ; 7: 365, 2006 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-16872538

RESUMO

BACKGROUND: Identification of protein interaction networks has received considerable attention in the post-genomic era. The currently available biochemical approaches used to detect protein-protein interactions are all time and labour intensive. Consequently there is a growing need for the development of computational tools that are capable of effectively identifying such interactions. RESULTS: Here we explain the development and implementation of a novel Protein-Protein Interaction Prediction Engine termed PIPE. This tool is capable of predicting protein-protein interactions for any target pair of the yeast Saccharomyces cerevisiae proteins from their primary structure and without the need for any additional information or predictions about the proteins. PIPE showed a sensitivity of 61% for detecting any yeast protein interaction with 89% specificity and an overall accuracy of 75%. This rate of success is comparable to those associated with the most commonly used biochemical techniques. Using PIPE, we identified a novel interaction between YGL227W (vid30) and YMR135C (gid8) yeast proteins. This lead us to the identification of a novel yeast complex that here we term vid30 complex (vid30c). The observed interaction was confirmed by tandem affinity purification (TAP tag), verifying the ability of PIPE to predict novel protein-protein interactions. We then used PIPE analysis to investigate the internal architecture of vid30c. It appeared from PIPE analysis that vid30c may consist of a core and a secondary component. Generation of yeast gene deletion strains combined with TAP tagging analysis indicated that the deletion of a member of the core component interfered with the formation of vid30c, however, deletion of a member of the secondary component had little effect (if any) on the formation of vid30c. Also, PIPE can be used to analyse yeast proteins for which TAP tagging fails, thereby allowing us to predict protein interactions that are not included in genome-wide yeast TAP tagging projects. CONCLUSION: PIPE analysis can predict yeast protein-protein interactions. Also, PIPE analysis can be used to study the internal architecture of yeast protein complexes. The data also suggests that a finite set of short polypeptide signals seem to be responsible for the majority of the yeast protein-protein interactions.


Assuntos
Biologia Computacional/métodos , Peptídeos/química , Mapeamento de Interação de Proteínas/métodos , Proteínas/química , Proteômica/métodos , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Algoritmos , Sequência de Bases , Dados de Sequência Molecular , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Sensibilidade e Especificidade , Software , Técnicas do Sistema de Duplo-Híbrido
9.
Cleve Clin J Med ; 83(1): 15, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26760514
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