Lineage-based scaling of germline intercellular bridges during oogenesis.

The size of subcellular structures must be tightly controlled to maintain normal cell function. Despite its importance, few studies have determined how the size of organelles or other structures is maintained during development, when cells are growing, dividing and rearranging. The developing Drosophila egg chamber is a powerful model in which to study the relative growth rates of subcellular structures. The egg chamber contains a cluster of 16 germline cells, which are connected through intercellular bridges called ring canals. As the egg chamber grows, the germline cells and the ring canals that connect them increase in size. Here, we demonstrate that ring canal size scaling is related to lineage; the largest, 'first-born' ring canals increase in size at a relatively slower rate than ring canals derived from subsequent mitotic divisions. This lineage-based scaling relationship is maintained even if directed transport is reduced, ring canal size is altered, or in egg chambers with twice as many germline cells. Analysis of lines that produce larger or smaller mature eggs reveals that different strategies could be used to alter final egg size.

Integrating Genomics into Healthcare: A Global Responsibility.

Genomic sequencing is rapidly transitioning into clinical practice, and implementation into healthcare systems has been supported by substantial government investment, totaling over US$4 billion, in at least 14 countries. These national genomic-medicine initiatives are driving transformative change under real-life conditions while simultaneously addressing barriers to implementation and gathering evidence for wider adoption. We review the diversity of approaches and current progress made by national genomic-medicine initiatives in the UK, France, Australia, and US and provide a roadmap for sharing strategies, standards, and data internationally to accelerate implementation.

Prompt-facilitated learning: The development of unprompted memory integration and subsequent self-derivation.

What are the boundaries that limit expansion of semantic knowledge across development? One striking contender is the necessity of a prompt to integrate and self-generate new information. The present research was an investigation of 7-9-year-olds' and 18-22-year-olds' prompted versus unprompted memory integration and subsequent self-derivation of new knowledge. Children and adults (Experiments 1 and 2, respectively) were exposed to sets of novel, true facts that could be integrated to self-derive new knowledge. On some trials they were prompted to integrate and self-derive and on others they were not. Both children and young adults capitalized more effectively on prompted opportunities to self-derive compared with unprompted opportunities, and the mechanism of this difference in performance likely underlies memory integration. Thus, the current work illustrates the importance of the conditions under which memory integration occurs, regardless of age. Results also offer evidence consistent with developmental change in unprompted integration and self-derivation performance, such that children and adults may engage the process of self-derivation differently. This work is particularly important in highlighting the necessity of appropriate scaffolding to foster successful learning opportunities and understanding the conditions under which semantic knowledge is accumulated.

Weight Loss Strategies Used by Army Reserve Officer Training Corps Cadets: Implication for Student Health and Wellness Services.

Background: Maintaining a healthy weight is a military requirement for the Reserve Officer Training Corps (ROTC) cadets. Male and female soldiers often have different approaches to maintaining a healthy weight and mobile health (m-health) tools can be harnessed and tailored to the needs of individual cadets. Objectives: This study examined gender differences in technology use, weight loss strategies, information needed to maintain a healthy weight, and willingness to participate in m-health research and programs. Materials and Methods: A self-administered survey was completed by 404 cadets from ROTC programs in Florida in 2017. Results: Most owned smartphones and used them as their primary internet access. Women had significantly lower body mass index than men (p = 0.037). Most used healthy weight loss strategies, including increasing physical activity, reducing sweets, and reducing fried foods. Women were more likely than men to reduce fried foods (p < 0.0003) and sweets (p = 0.020). Most reported a willingness to participate in m-health weight management research and programs, with women more willing to do so (p = 0.038). Most were willing to participate in m-health programs that used text messages, food/activity/sleep apps, smart watches/fitness trackers, and stress management/anxiety apps. Women were more willing to participate in programs that used apps for stress/anxiety management (p = 0.004) and to track food/activity/sleep (p < 0.0001). Most needed information on eating healthy on a budget and eating healthy on-the-run. Conclusions: Opportunities exist for college health and wellness professionals to use a variety of m-health tools and apps to promote general health and wellness and to help cadets achieve and maintain a healthy weight.

α/ß-Peptide Foldamers Targeting Intracellular Protein-Protein Interactions with Activity in Living Cells.

Peptides can be developed as effective antagonists of protein-protein interactions, but conventional peptides (i.e., oligomers of l-α-amino acids) suffer from significant limitations in vivo. Short half-lives due to rapid proteolytic degradation and an inability to cross cell membranes often preclude biological applications of peptides. Oligomers that contain both α- and ß-amino acid residues ("α/ß-peptides") manifest decreased susceptibility to proteolytic degradation, and when properly designed these unnatural oligomers can mimic the protein-recognition properties of analogous "α-peptides". This report documents an extension of the α/ß-peptide approach to target intracellular protein-protein interactions. Specifically, we have generated α/ß-peptides based on a "stapled" Bim BH3 α-peptide, which contains a hydrocarbon cross-link to enhance α-helix stability. We show that a stapled α/ß-peptide can structurally and functionally mimic the parent stapled α-peptide in its ability to enter certain types of cells and block protein-protein interactions associated with apoptotic signaling. However, the α/ß-peptide is nearly 100-fold more resistant to proteolysis than is the parent stapled α-peptide. These results show that backbone modification, a strategy that has received relatively little attention in terms of peptide engineering for biomedical applications, can be combined with more commonly deployed peripheral modifications such as side chain cross-linking to produce synergistic benefits.

Generative and active engagement in learning neuroscience: A comparison of self-derivation and rephrase.

It is crucial to identify cognitive mechanisms that support knowledge growth. One such mechanism that is known to improve learning outcomes is generative processing: the construction of novel information beyond what is directly taught. In this study of college students, we investigate the learning outcomes associated with the generative process of self-derivation through integration, the integration of multiple related facts to generate novel information. We compare the effects of self-derivation versus an active rephrase control condition on retrieval, application, and organization of neuroscience classroom content. In the self-derivation condition, learners were prompted to generate inferences based on integration of two explicitly-taught facts. In the rephrase condition, learners were explicitly provided these inferences and asked to rephrase them. We found few overall differences between learning manipulation conditions. However, we found that, regardless of the learning manipulation condition to which learners were exposed, learners generated their own information on some trials. This generation predicted success on retrieval and application of learned information. Further, self-derivation, when successful, led to particularly high rates of retrieval when compared with active rephrase. These findings inform theory on generative processing, and demonstrate that self-derivation is a mechanism of knowledge growth that may be useful for retrieval.

Individual differences diminish the pretest effect under productive memory conditions.

Pretesting, or asking a test question prior to the onset of learning, is a well-established means of enhancing learning. Research on pretesting has focused primarily on direct factual learning outcomes. Yet building a coherent knowledge base also depends on productive memory processes that permit going beyond the information directly given. In the specific productive process of self-derivation through memory integration, individual differences are prominent; verbal comprehension is a consistent predictor. In the current work, we integrated these research trends by testing the extent to which pretesting enhances learning through productive memory processes and the role played by individual differences in verbal comprehension. Across four within-subjects experiments, we assessed the pretest effect after accounting for variability associated with verbal comprehension. In Experiments 1-3, we assessed the productive memory process of self-derivation through memory integration. Adults were more successful on pretest trials compared to control (i.e., no pretest) trials, but this effect was no longer significant after controlling for verbal comprehension. This pattern emerged when we used stem-fact pretests (Experiment 1) and integration-fact pretests (Experiment 2) to probe self-derivation across single-sentence stimuli and replicated when we used stimuli more akin to everyday learning materials (i.e., text passages and photographs; Experiment 3). In Experiment 4, we shifted the test target from productive processes to fact recall and found the pretest effect held even after controlling for verbal comprehension. This research bridges the pretest and productive process literature to provide novel insight into ways of maximizing learning. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Small molecule drug metabolite synthesis and identification: why, when and how?

The drug discovery and development process encompasses the interrogation of metabolites arising from the biotransformation of drugs. Here we look at why, when and how metabolites of small-molecule drugs are synthesised from the perspective of a specialist contract research organisation, with particular attention paid to projects for which regulatory oversight is relevant during this journey. To illustrate important aspects, we look at recent case studies, trends and learnings from our experience of making and identifying metabolites over the past ten years, along with with selected examples from the literature.

Impact of a Health Coach-Led, Text-Based Digital Behavior Change Intervention on Weight Loss and Psychological Well-Being in Patients Receiving a Procedureless Intragastric Balloon Program: Prospective Single-Arm Study.

BACKGROUND: Digital health interventions show promise for weight management. However, few text-based behavior change interventions have been designed to support patients receiving intragastric balloons, and none have simultaneously evaluated weight loss, psychological well-being, and behavior change despite the crucial interplay of these factors in weight management. OBJECTIVE: This study aims to assess whether a health coach-led, asynchronous, text-based digital behavior change coaching intervention (DBCCI) delivered to participants receiving an intragastric balloon and its aftercare program was feasible and acceptable to participants and supported improved outcomes, including weight loss, psychological well-being, and lifestyle behavior change conducive to weight loss maintenance. METHODS: This 12-month, single-arm prospective study enrolled adults aged 21 to 65 years with BMI ≥27 kg/m2 receiving a procedureless intragastric balloon (PIGB) at 5 bariatric clinics in the United Kingdom and the Netherlands. Participants received the DBCCI and the clinic-led PIGB aftercare program (remotely delivered) for 6 months after PIGB placement and then no intervention for an additional 6 months. The DBCCI was an evidence-based, personalized intervention wherein health coaches supported participants via exchanged asynchronous in-app text-based messages. Over the 12-month study, we assessed percentage of total body weight loss and psychological well-being via self-administered validated questionnaires (Warwick-Edinburgh Mental Wellbeing Scale, Generalized Anxiety Disorder Scale, Impact of Weight on Quality of Life-Lite-Clinical Trials Version, Loss of Control Over Eating Scale-Brief, Weight Efficacy Lifestyle Questionnaire-Short Form, and Barriers to Being Active Quiz). Participant engagement with and acceptability of the intervention were assessed via self-reported surveys. RESULTS: Overall, 107 participants (n=96, 89.7% female; mean baseline BMI 35.4, SD 5.4 kg/m2) were included in the analysis. Mean total body weight loss was 13.5% (SEM 2.3%) at the end of the DBCCI and 11.22% (SEM 2.3%) at the 12-month follow-up (P<.001). Improvements were observed for all psychological well-being measures throughout the 12 months except for the Generalized Anxiety Disorder Scale (improvement at month 1) and Barriers to Being Active Quiz (improvements at months 3 and 6). Surveys showed high levels of engagement with and acceptability of the DBCCI. CONCLUSIONS: This study provides evidence that the health coach-led, asynchronous, text-based DBCCI was engaging and acceptable to participants with overweight and obesity. The DBCCI, delivered alongside the PIGB and its aftercare program, supported improved weight loss outcomes and psychological well-being versus baseline and was associated with lifestyle behavior changes known to help achieve and maintain long-term weight loss and improved health outcomes. Follow-up findings suggest a potential need for longer-term, more intense coaching to focus on weight loss maintenance and support ongoing self-coaching. This could be achieved by leveraging generative artificial intelligence to provide ongoing automated behavior change coaching support to augment human-led care. TRIAL REGISTRATION: ClinicalTrials.gov NCT05884606; https://clinicaltrials.gov/study/NCT05884606.

Dendritic spine head diameter predicts episodic memory performance in older adults.

Episodic memory in older adults is varied and perceived to rely on numbers of synapses or dendritic spines. We analyzed 2157 neurons among 128 older individuals from the Religious Orders Study and Rush Memory and Aging Project. Analysis of 55,521 individual dendritic spines by least absolute shrinkage and selection operator regression and nested model cross-validation revealed that the dendritic spine head diameter in the temporal cortex, but not the premotor cortex, improved the prediction of episodic memory performance in models containing ß amyloid plaque scores, neurofibrillary tangle pathology, and sex. These findings support the emerging hypothesis that, in the temporal cortex, synapse strength is more critical than quantity for memory in old age.

Areal specializations in the morpho-electric and transcriptomic properties of primate layer 5 extratelencephalic projection neurons.

Large-scale analysis of single-cell gene expression has revealed transcriptomically defined cell subclasses present throughout the primate neocortex with gene expression profiles that differ depending upon neocortical region. Here, we test whether the interareal differences in gene expression translate to regional specializations in the physiology and morphology of infragranular glutamatergic neurons by performing Patch-seq experiments in brain slices from the temporal cortex (TCx) and motor cortex (MCx) of the macaque. We confirm that transcriptomically defined extratelencephalically projecting neurons of layer 5 (L5 ET neurons) include retrogradely labeled corticospinal neurons in the MCx and find multiple physiological properties and ion channel genes that distinguish L5 ET from non-ET neurons in both areas. Additionally, while infragranular ET and non-ET neurons retain distinct neuronal properties across multiple regions, there are regional morpho-electric and gene expression specializations in the L5 ET subclass, providing mechanistic insights into the specialized functional architecture of the primate neocortex.

Lineage-based scaling of germline intercellular bridges during oogenesis.

The size of subcellular structures must be tightly controlled to maintain normal cell function; this is especially important when cells are part of developing tissues or organs. Despite its importance, few studies have determined how the size of organelles or other structures is maintained during tissue growth, when cells are growing, dividing, and rearranging. The developing egg chamber is a powerful model in which to study the relative growth rates of subcellular structures. The egg chamber contains a cluster of sixteen germ cells, which are connected through intercellular bridges called ring canals. Ring canals are formed following incomplete cytokinesis after each of four germ cell divisions. As the egg chamber grows, the nurse cells and the ring canals that connect them increase in size. Here, we demonstrate that ring canal size scaling is related to their lineage; the largest, "first born" ring canals grow at a relatively slower rate than ring canals derived from subsequent mitotic divisions. This lineage-based scaling relationship is maintained even if directed transport is reduced, ring canal size is altered, or if the germ cells go through an additional mitotic division. Further, we propose that changes in ring canal scaling could provide a mechanism to alter egg size.

Open Source Antibiotics: Simple Diarylimidazoles Are Potent against Methicillin-Resistant Staphylococcus aureus.

Antimicrobial resistance (AMR) is widely acknowledged as one of the most serious public health threats facing the world, yet the private sector finds it challenging to generate much-needed medicines. As an alternative discovery approach, a small array of diarylimidazoles was screened against the ESKAPE pathogens, and the results were made publicly available through the Open Source Antibiotics (OSA) consortium (https://github.com/opensourceantibiotics). Of the 18 compounds tested (at 32 µg/mL), 15 showed >90% growth inhibition activity against methicillin-resistant Staphylococcus aureus (MRSA) alone. In the subsequent hit-to-lead optimization of this chemotype, 147 new heterocyclic compounds containing the diarylimidazole and other core motifs were synthesized and tested against MRSA, and their structure-activity relationships were identified. While potent, these compounds have moderate to high intrinsic clearance and some associated toxicity. The best overall balance of parameters was found with OSA_975, a compound with good potency, good solubility, and reduced intrinsic clearance in rat hepatocytes. We have progressed toward the knowledge of the molecular target of these phenotypically active compounds, with proteomic techniques suggesting TGFBR1 is potentially involved in the mechanism of action. Further development of these compounds toward antimicrobial medicines is available to anyone under the licensing terms of the project.

ADHD and Substance Use Disorders in Young People: Considerations for Evaluation, Diagnosis, and Pharmacotherapy.

Co-occurring ADHD and substance use disorder (SUD) is a common clinical presentation associated with significant impairment requiring careful evaluation, diagnosis, and treatment. Treatment with medication, along with cognitive behavioral therapy, is generally regarded as effective in addressing symptoms and impairments associated with both disorders. Options for pharmacotherapy include stimulant and nonstimulant therapies administered with careful monitoring of dosage and compliance to optimize efficacy. In high-risk groups such as college students and/or those with SUD, prescribers should address risks of stimulant misuse and diversion through patient and family education, medication monitoring, and other risk-reducing practices.

Invasion, isolation and evolution shape population genetic structure in Campanula rotundifolia.

The distribution and genetic structure of most plant species in Britain and Ireland bear the imprint of the last ice age. These patterns were largely shaped by random processes during recolonization but, in angiosperms, whole-genome duplication may also have been important. We investigate the distribution of cytotypes of Campanula rotundifolia, considering DNA variation, postglacial colonization, environmental partitioning and reproductive barriers. Cytotypes and genome size variation from across the species' range were determined by flow cytometry and genetic variation was assessed using cpDNA markers. A common garden study examined growth and flowering phenology of tetraploid, pentaploid and hexaploid cytotypes and simulated a contact zone for investigation of reproductive barriers. Irish populations were entirely hexaploid. In Britain, hexaploids occurred mostly in western coastal populations which were allopatric with tetraploids, and in occasional sympatric inland populations. Chloroplast markers resolved distinct genetic groups, related to cytotype and geographically segregated; allopatric hexaploids were distinct from tetraploids, whereas sympatric hexaploids were not. Genome downsizing occurred between cytotypes. Progeny of open-pollinated clones from the contact zone showed that maternal tetraploids rarely produced progeny of other cytotypes, whereas the progeny of maternal hexaploids varied, with frequent pentaploids and aneuploids. The presence of distinctive hexaploid chloroplast types in Ireland, Scottish islands and western mainland Britain indicates that its establishment preceded separation of these land masses by sea-level rise c. 16 000 years BP. This group did not originate from British tetraploids and probably diverged before postglacial invasion from mainland Europe. The combination of cytotype, molecular, contact zone and common garden data shows an overall pattern reflecting postglacial colonization events, now maintained by geographic separation, together with more recent occasional local in situ polyploidisation. Reproductive barriers favour the persistence of the tetraploid to the detriment of the hexaploid.

Biotransformation: Impact and Application of Metabolism in Drug Discovery.

Biotransformation has a huge impact on the efficacy and safety of drugs. Ultimately the effects of metabolism can be the lynchpin in the discovery and development cycle of a new drug. This article discusses the impact and application of biotransformation of drugs by mammalian systems, microorganisms, and recombinant enzymes, covering active and reactive metabolites, the impact of the gut microbiome on metabolism, and how insights gained from biotransformation studies can influence drug design from the combined perspectives of a CRO specializing in a range of biotransformation techniques and pharma biotransformation scientists. We include a commentary on how biology-driven approaches can complement medicinal chemistry strategies in drug optimization and the in vitro and surrogate systems available to explore and exploit biotransformation.

The inflammatory cytokine tumor necrosis factor-alpha generates an autocrine tumor-promoting network in epithelial ovarian cancer cells.

Constitutive expression of the inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) is characteristic of malignant ovarian surface epithelium. We investigated the hypothesis that this autocrine action of TNF-alpha generates and sustains a network of other mediators that promote peritoneal cancer growth and spread. When compared with two ovarian cancer cell lines that did not make TNF-alpha, constitutive production of TNF-alpha was associated with greater release of the chemokines CCL2 and CXCL12, the cytokines interleukin-6 (IL-6) and macrophage migration-inhibitory factor (MIF), and the angiogenic factor vascular endothelial growth factor (VEGF). TNF-alpha production was associated also with increased peritoneal dissemination when the ovarian cancer cells were xenografted. We next used RNA interference to generate stable knockdown of TNF-alpha in ovarian cancer cells. Production of CCL2, CXCL12, VEGF, IL-6, and MIF was decreased significantly in these cells compared with wild-type or mock-transfected cells, but in vitro growth rates were unaltered. Tumor growth and dissemination in vivo were significantly reduced when stable knockdown of TNF-alpha was achieved. Tumors derived from TNF-alpha knockdown cells were noninvasive and well circumscribed and showed high levels of apoptosis, even in the smallest deposits. This was reflected in reduced vascularization of TNF-alpha knockdown tumors. Furthermore, culture supernatants from such cells failed to stimulate endothelial cell growth in vitro. We conclude that autocrine production of TNF-alpha by ovarian cancer cells stimulates a constitutive network of other cytokines, angiogenic factors, and chemokines that may act in an autocrine/paracrine manner to promote colonization of the peritoneum and neovascularization of developing tumor deposits.

Tree growth and management in Ugandan agroforestry systems: effects of root pruning on tree growth and crop yield.

Tree root pruning is a potential tool for managing belowground competition when trees and crops are grown together in agroforestry systems. We investigated the effects of tree root pruning on shoot growth and root distribution of Alnus acuminata (H.B. & K.), Casuarina equisetifolia L., Grevillea robusta A. Cunn. ex R. Br., Maesopsis eminii Engl. and Markhamia lutea (Benth.) K. Schum. and on yield of adjacent crops in sub-humid Uganda. The trees were 3 years old at the commencement of the study, and most species were competing strongly with crops. Tree roots were pruned 41 months after planting by cutting and back-filling a trench to a depth of 0.3 m, at a distance of 0.3 m from the trees, on one side of the tree row. The trench was reopened and roots recut at 50 and 62 months after planting. We assessed the effects on tree growth and root distribution over a 3 year period, and crop yield after the third root pruning at 62 months. Overall, root pruning had only a slight effect on aboveground tree growth: height growth was unaffected and diameter growth was reduced by only 4%. A substantial amount of root regrowth was observed by 11 months after pruning. Tree species varied in the number and distribution of roots, and C. equisetifolia and M. lutea had considerably more roots per unit of trunk volume than the other species, especially in the surface soil layers. Casuarina equisetifolia and M. eminii were the tree species most competitive with crops and G. robusta and M. lutea the least competitive. Crop yield data provided strong evidence of the redistribution of root activity following root pruning, with competition increasing on the unpruned side of tree rows. Thus, one-sided root pruning will be useful in only a few circumstances.

Endothelins induce CCR7 expression by breast tumor cells via endothelin receptor A and hypoxia-inducible factor-1.

Endothelin expression is increased in breast tumors and is associated with invasion and metastasis, whereas CCR7 expression by breast tumor cells may have a role in the organ specificity of breast cancer spread. In this article, we have analyzed whether endothelins influence breast tumor cell expression of the chemokine receptor CCR7. Stimulation of human breast tumor cell lines with endothelins increased cell surface expression of CCR7 via endothelin receptor A. The iron chelators desferrioxamine and cobalt chloride, which induce hypoxia-inducible factor (HIF)-mediated transcription, also increased CCR7 expression; transfection of a dominant-negative version of the HIF regulatory subunit, HIF-1alpha, into MCF-7 cells abolished CCR7 induction by endothelins, indicating that increased expression is due to HIF-1 stabilization. Endothelin stimulation promoted invasion toward the CCR7 ligands CCL19 and CCL21. Endothelin-mediated chemokine-independent invasion itself is dependent on CCR7 activity and could be abolished using a CCR7-neutralizing monoclonal antibody. In human breast carcinomas, mRNA expression of endothelins correlated with the level of CCR7 expression, both of which were associated with the presence of lymph node metastases. Expression of the CCR7 ligands CCL19 and CCL21 was also higher in breast cancer patients with lymph node involvement compared with those without, but expression of these chemokines did not correlate with endothelin expression. These data show that CCR7 may be regulated by the breast tumor microenvironment and further support the use of endothelin receptor antagonists in the treatment of invasive and metastatic breast cancer.