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1.
Nat Commun ; 15(1): 5567, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956087

ABSTRACT

Diabetes involves the death or dysfunction of pancreatic ß-cells. Analysis of bulk sequencing from human samples and studies using in vitro and in vivo models suggest that endoplasmic reticulum and inflammatory signaling play an important role in diabetes progression. To better characterize cell type-specific stress response, we perform multiplexed single-cell RNA sequencing to define the transcriptional signature of primary human islet cells exposed to endoplasmic reticulum and inflammatory stress. Through comprehensive pair-wise analysis of stress responses across pancreatic endocrine and exocrine cell types, we define changes in gene expression for each cell type under different diabetes-associated stressors. We find that ß-, α-, and ductal cells have the greatest transcriptional response. We utilize stem cell-derived islets to study islet health through the candidate gene CIB1, which was upregulated under stress in primary human islets. Our findings provide insights into cell type-specific responses to diabetes-associated stress and establish a resource to identify targets for diabetes therapeutics.


Subject(s)
Endoplasmic Reticulum Stress , Insulin-Secreting Cells , Islets of Langerhans , Humans , Endoplasmic Reticulum Stress/genetics , Islets of Langerhans/metabolism , Insulin-Secreting Cells/metabolism , Calcium-Binding Proteins/metabolism , Calcium-Binding Proteins/genetics , Single-Cell Analysis , Glucagon-Secreting Cells/metabolism , Sequence Analysis, RNA , Transcriptome , Stress, Physiological
2.
Behav Sci (Basel) ; 14(6)2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38920820

ABSTRACT

Sex differences have been a rarely addressed aspect in digital game-based learning (DGBL). Likewise, mixed results have been presented regarding the effects according to sex and the conditions that generate these effects. The present work studied the effects of a drill-and-practice mathematical game on primary students. The study focused on an analysis by sex, measuring motivation and learning in the practice activity. Also, two instructional mechanics were considered regarding the question answering to search for possible differences: a multiple-try feedback (MTF) condition and a single-try feedback (STF) condition. A total of 81 students from four courses and two schools participated in the intervention. The study's main findings were as follows: (a) the girls outperformed the boys in terms of the students' learning gains; (b) the girls presented lower levels of competence and autonomy than the boys; (c) under MTF, the girls presented lower levels of autonomy but no differences in competence contrasted with the boys; (d) under STF, the girls presented lower levels of competence but no differences in autonomy contrasted with the boys; (e) no sex differences existed in interest, effort, and value, in general, as per the instructional condition. This study enhances the knowledge of sex differences under diverse instructional settings, in particular providing insights into the possible differences by sex when varying the number of attempts provided to students.

4.
Sci Rep ; 13(1): 17578, 2023 10 16.
Article in English | MEDLINE | ID: mdl-37845233

ABSTRACT

This work analyzes the implementation of an artificial mechanism inspired by a biological somatic marker that ables a passenger agent to both, react to changes in the service, as well as keep said reactions as a memory for future decisions. An artificial mental model was designed, and the passenger agent was implemented as an autonomous decision-making system, where both, the choice of the transport operator and the evaluation of the received service were fully delegated to the system. The evaluation of the service experience is not only based on rational aspects (such as the cost of the trip) but also on subjective aspects related to the satisfaction level derived from the passenger's experience. The experimental scenario considered 10,000 trip requests simulated within an artificial map that emulates characteristics that are usually present in a city, such as vehicular congestion, the unsafety of certain streets, or the benefits of an area with tourist interest. The results show that the option to travel under a transport operator with a touristic profile is a trend. Unlike current cases in the industry, this research work explores the scenario where the passenger can have as a client a trip profile with memory, differentiated from other clients, and can receive more than one trip proposal for the same trip request, according to the different conditions that the passenger is looking for.


Subject(s)
Transportation , Travel , Humans , Transportation/methods , Cities , Tourism
5.
PDA J Pharm Sci Technol ; 77(6): 472-484, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-37580129

ABSTRACT

The sterile barrier is one of the most important aspects of the container closure integrity (CCI) for a prefilled syringe (PFS or syringe). This crucial barrier enables the protection of the syringe contents from contamination. The plunger stopper (stopper) is naturally in a stationary position that is controlled by the static friction between the plunger stopper and the syringe barrel wall. When an applied force is greater than the static friction, which is commonly known as the break-loose force, the plunger stopper will move. In such conditions, the stopper movement can further be increased if an air bubble (AB) is introduced between the liquid fill in the syringe and the stopper during the stoppering process. This additional movement can occur when the pressure differential between the gaseous headspace inside the syringe and the external atmosphere is large enough that the force exerted on the stopper exceeds the break-loose force of the syringe. This can occur during altitude or temperature changes incurred during aerial or mountainous transport. This article, therefore, discusses the relationship between stopper movement and initial headspace (air bubble size/ABS) in a 2.25 mL Type I glass syringe using theoretical and empirical approaches. The results showed the maximum initial headspace needed to enable CCI at specified altitudes and plunger stopper movements for the syringe-plunger stopper combination used in the study. Empirical data also indicated that CCI can be maintained for this syringe-plunger stopper combination with up to 9.0 mm initial headspace at altitudes up to 17,000 feet.


Subject(s)
Drug Packaging , Syringes , Drug Packaging/methods , Drug Contamination/prevention & control
7.
Am J Physiol Gastrointest Liver Physiol ; 325(2): G196-G211, 2023 08 01.
Article in English | MEDLINE | ID: mdl-37310750

ABSTRACT

Colorectal cancer (CRC) tumorigenesis and progression are linked to common oncogenic mutations, especially in the tumor suppressor APC, whose loss triggers the deregulation of TCF4/ß-Catenin activity. CRC tumorigenesis is also driven by multiple epimutational modifiers such as transcriptional regulators. We describe the common (and near-universal) activation of the zinc finger transcription factor and Let-7 target PLAGL2 in CRC and find that it is a key driver of intestinal epithelial transformation. PLAGL2 drives proliferation, cell cycle progression, and anchorage-independent growth in CRC cell lines and nontransformed intestinal cells. Investigating effects of PLAGL2 on downstream pathways revealed very modest effects on canonical Wnt signaling. Alternatively, we find pronounced effects on the direct PLAGL2 target genes IGF2, a fetal growth factor, and ASCL2, an intestinal stem cell-specific bHLH transcription factor. Inactivation of PLAGL2 in CRC cell lines has pronounced effects on ASCL2 reporter activity. Furthermore, ASCL2 expression can partially rescue deficits of proliferation and cell cycle progression caused by depletion of PLAGL2 in CRC cell lines. Thus, the oncogenic effects of PLAGL2 appear to be mediated via core stem cell and onco-fetal pathways, with minimal effects on downstream Wnt signaling.NEW & NOTEWORTHY A Let-7 target called PLAGL2 drives oncogenic transformation via Wnt-independent pathways. This work illustrates the robust effects of this zinc finger transcription factor in colorectal cancer (CRC) cell lines and nontransformed intestinal epithelium, with effects mediated, in part, via the direct target genes ASCL2 and IGF2. This has implications for the role of PLAGL2 in activation of onco-fetal and onco-stem cell pathways, contributing to immature and highly proliferative phenotypes in CRC.


Subject(s)
Colorectal Neoplasms , Humans , Colorectal Neoplasms/metabolism , Cell Line, Tumor , Transcription Factors/genetics , Transcription Factors/metabolism , Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , beta Catenin/metabolism , Cell Transformation, Neoplastic/genetics , Wnt Signaling Pathway , Carcinogenesis/genetics , Gene Expression Regulation, Neoplastic , Cell Proliferation/genetics , DNA-Binding Proteins/metabolism , RNA-Binding Proteins/genetics
8.
Nat Cell Biol ; 25(6): 904-916, 2023 06.
Article in English | MEDLINE | ID: mdl-37188763

ABSTRACT

Insulin-producing ß cells created from human pluripotent stem cells have potential as a therapy for insulin-dependent diabetes, but human pluripotent stem cell-derived islets (SC-islets) still differ from their in vivo counterparts. To better understand the state of cell types within SC-islets and identify lineage specification deficiencies, we used single-nucleus multi-omic sequencing to analyse chromatin accessibility and transcriptional profiles of SC-islets and primary human islets. Here we provide an analysis that enabled the derivation of gene lists and activity for identifying each SC-islet cell type compared with primary islets. Within SC-islets, we found that the difference between ß cells and awry enterochromaffin-like cells is a gradient of cell states rather than a stark difference in identity. Furthermore, transplantation of SC-islets in vivo improved cellular identities overtime, while long-term in vitro culture did not. Collectively, our results highlight the importance of chromatin and transcriptional landscapes during islet cell specification and maturation.


Subject(s)
Insulins , Islets of Langerhans , Pluripotent Stem Cells , Humans , Multiomics , Cell Differentiation/genetics , Pluripotent Stem Cells/metabolism , Chromatin/genetics , Chromatin/metabolism , Insulins/metabolism
9.
Genes (Basel) ; 14(3)2023 03 03.
Article in English | MEDLINE | ID: mdl-36980915

ABSTRACT

Genetic analysis of historical museum collections presents an opportunity to clarify the evolutionary history of understudied primate groups, improve taxonomic inferences, and inform conservation efforts. Among the most understudied primate groups, slow and pygmy lorises (genera Nycticebus and Xanthonycticebus) are nocturnal strepsirrhines found in South and Southeast Asia. Previous molecular studies have supported five species, but studies using morphological data suggest the existence of at least nine species. We sequenced four mitochondrial loci, CO1, cytb, d-loop, and ND4, for a total of 3324 aligned characters per sample from 41 historical museum specimens for the most comprehensive geographic coverage to date for these genera. We then combined these sequences with a larger dataset composed of samples collected in Vietnam as well as previously published sequences (total sample size N = 62). We inferred phylogenetic relationships using Bayesian inference and maximum likelihood methods based on data from each locus and on concatenated sequences. We also inferred divergence dates for the most recent common ancestors of major lineages using a BEAST analysis. Consistent with previous studies, we found support for Xanthonycticebus pygmaeus as a basal taxon to the others in the group. We also confirmed the separation between lineages of X. pygmaeus from northern Vietnam/Laos/China and southern Vietnam/Cambodia and included a taxonomic revision recognizing a second taxon of pygmy loris, X. intermedius. Our results found support for multiple reciprocally monophyletic taxa within Borneo and possibly Java. The study will help inform conservation management of these trade-targeted animals as part of a genetic reference database for determining the taxonomic unit and provenance of slow and pygmy lorises confiscated from illegal wildlife trade activities.


Subject(s)
Lorisidae , Animals , Phylogeny , Lorisidae/anatomy & histology , Lorisidae/genetics , Bayes Theorem , Asia, Southeastern , Genetic Variation/genetics
10.
PDA J Pharm Sci Technol ; 77(1): 45-52, 2023.
Article in English | MEDLINE | ID: mdl-35987519

ABSTRACT

As the complexities of the pharmaceuticals needed to prevail over serious diseases continue to grow, the need for technologies to enable their efficient storage and delivery are as essential as ever. Lately, drugs such as vaccines, proteins, and stem cells are increasingly requiring frozen storage to maintain their efficacies before use. Notably, the advent of cellular therapy products has invariably elevated the need for cryopreservation and frozen storage of cellular starting materials, intermediates, and/or final product. The container closure integrity (CCI)-which is a major requirement for aseptic or sterile packaging systems-at these extremely low temperatures has not been fully understood. For vial-based systems particularly, the commonly used rubber stoppers are expected to lose their elastic properties below their glass transition temperatures, suggesting a potential temporary loss of sealability under frozen storage conditions and posing a risk to CCI. The measurement of the CCI at these conditions such as -80°C is therefore critical; a process that can be very challenging. Previous works had explored the use of Oxygen Headspace Analysis to measure CCI at low temperatures. Here, we present the evaluation of the CCI of rubber-stoppered aluminosilicate glass vials (Valor®) and plastic vials (Crystal Zenith®) using the helium leak CCI test method at -80°C, with correlation to residual seal force (RSF). The results and their implications are then discussed with regard to the suitability of certain packaging components as frozen storage container closure systems.


Subject(s)
Rubber , Technology, Pharmaceutical , Technology, Pharmaceutical/methods , Rubber/chemistry , Drug Packaging/methods , Freezing , Cold Temperature , Pharmaceutical Preparations , Glass
11.
Stem Cell Reports ; 11(2): 410-424, 2018 08 14.
Article in English | MEDLINE | ID: mdl-30017821

ABSTRACT

Intestinal epithelial stem cell (IESC) fate is promoted by two major transcriptional regulators, the TCF4/ß-catenin complex and ASCL2, which drive expression of IESC-specific factors, including Lgr5, Ephb2, and Rnf43. Canonical Wnt signaling via TCF4/ß-catenin directly transactivates Ascl2, which in turn auto-regulates its own expression. Conversely, Let-7 microRNAs antagonize the IESC lineage by repressing specific mRNA targets. Here, we identify the zinc finger transcription factor PLAGL2 as a Let-7 target that regulates IESC fate. PLAGL2 drives an IESC expression signature, activates Wnt gene expression, and enhances a TCF/LEF reporter in intestinal organoids. In parallel, via cell-autonomous mechanisms, PLAGL2 is required for lineage clonal expansion and directly enhances expression of ASCL2. PLAGL2 also supports enteroid growth and survival in the context of Wnt ligand depletion. PLAGL2 expression is strongly associated with an IESC signature in colorectal cancer and may be responsible for contributing to the aberrant activation of an immature phenotype.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/genetics , DNA-Binding Proteins/metabolism , Epithelial Cells/metabolism , Intestinal Mucosa/metabolism , RNA-Binding Proteins/metabolism , Stem Cells/cytology , Stem Cells/metabolism , Transcription Factors/metabolism , Transcriptional Activation , Animals , Biomarkers , Cell Culture Techniques , Cell Line, Tumor , DNA-Binding Proteins/genetics , Humans , Mice , RNA, Small Interfering/genetics , RNA-Binding Proteins/genetics , Signal Transduction , Transcription Factors/genetics
12.
Int J Paediatr Dent ; 23(5): 346-51, 2013 Sep.
Article in English | MEDLINE | ID: mdl-22738251

ABSTRACT

BACKGROUND: There is only limited information available in Chile regarding the frequency of biopsied oral lesions in paediatric patients. AIM: To determine the frequency of histologically diagnosed lesions in oral pathology specimens from paediatric patients in a Chilean population over a 15-year period. DESIGN: Oral and maxillofacial biopsy records of patients aged 16 years or under were retrieved by visual inspection from the archives of public and private Oral Pathology Health Services in Valdivia, Chile, during the period 1995-2010. Records that contained anatomical site and histopathological diagnoses of the specimen were included. The study population was divided into three age groups according to dentition stage. Oral lesions were classified as inflammatory/reactive, cystic, or tumour/tumour-like. RESULTS: A total of 542 biopsy specimens from children were found. These represented 20.6% of all oral biopsies. The average age was 11.1 years, with female predilection. The most common category of oral lesions was inflammatory/reactive (75.8%), followed by tumour/tumour-like (16.8%) and cystic (7.4%) lesions. The mucocele was the most commonly found lesion, followed by pyogenic granuloma and irritation fibroma, which taken together accounted for 63.8% of all paediatric oral biopsies. The most common localisation for lesions was the lower lip (50.3%). CONCLUSIONS: The vast majority of oral lesions found were predominantly inflammatory/reactive and benign types, although malignant lesions can present themselves in children.


Subject(s)
Stomatognathic Diseases/epidemiology , Adolescent , Biopsy , Child , Child, Preschool , Chile/epidemiology , Female , Humans , Infant , Male , Stomatognathic Diseases/pathology
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