Evolutionary history influences the microbiomes of a female symbiotic reproductive organ in cephalopods.

Many female squids and cuttlefishes have a symbiotic reproductive organ called the accessory nidamental gland (ANG) that hosts a bacterial consortium involved with egg defense against pathogens and fouling organisms. While the ANG is found in multiple cephalopod families, little is known about the global microbial diversity of these ANG bacterial symbionts. We used 16S rRNA gene community analysis to characterize the ANG microbiome from different cephalopod species and assess the relationship between host and symbiont phylogenies. The ANG microbiome of 11 species of cephalopods from four families (superorder: Decapodiformes) that span seven geographic locations was characterized. Bacteria of class Alphaproteobacteria, Gammaproteobacteria, and Flavobacteriia were found in all species, yet analysis of amplicon sequence variants by multiple distance metrics revealed a significant difference between ANG microbiomes of cephalopod families (weighted/unweighted UniFrac, Bray-Curtis, P = 0.001). Despite being collected from widely disparate geographic locations, members of the family Sepiolidae (bobtail squid) shared many bacterial taxa including (~50%) Opitutae (Verrucomicrobia) and Ruegeria (Alphaproteobacteria) species. Furthermore, we tested for phylosymbiosis and found a positive correlation between host phylogenetic distance and bacterial community dissimilarity (Mantel test r = 0.7). These data suggest that closely related sepiolids select for distinct symbionts from similar bacterial taxa. Overall, the ANGs of different cephalopod species harbor distinct microbiomes and thus offer a diverse symbiont community to explore antimicrobial activity and other functional roles in host fitness.IMPORTANCEMany aquatic organisms recruit microbial symbionts from the environment that provide a variety of functions, including defense from pathogens. Some female cephalopods (squids, bobtail squids, and cuttlefish) have a reproductive organ called the accessory nidamental gland (ANG) that contains a bacterial consortium that protects eggs from pathogens. Despite the wide distribution of these cephalopods, whether they share similar microbiomes is unknown. Here, we studied the microbial diversity of the ANG in 11 species of cephalopods distributed over a broad geographic range and representing 15-120 million years of host divergence. The ANG microbiomes shared some bacterial taxa, but each cephalopod species had unique symbiotic members. Additionally, analysis of host-symbiont phylogenies suggests that the evolutionary histories of the partners have been important in shaping the ANG microbiome. This study advances our knowledge of cephalopod-bacteria relationships and provides a foundation to explore defensive symbionts in other systems.

A Brief Review of Gepants.

PURPOSE OF REVIEW: Gepants are small molecules that antagonize calcitonin gene-related peptide (CGRP) receptors. Due to their favorable side effect profile and versatility in treating headaches acutely and preventively, gepants are preferred over triptans. We will cover the indications for the four FDA-approved gepants in adults: rimegepant, atogepant, ubrogepant, and zavegepant. This review will illustrate how gepants will continue to revolutionize the acute and preventive treatment of headaches. RECENT FINDINGS: Gepants are now available in oral tablet, dissolving tablet, and intra-nasal spray formulations. Recent studies have shown promising utility in treating the pre-headache or prodromal phase. They have favorable tolerability, no evidence for association with medication overuse, and remain a safer alternative in those who have cerebrovascular risk factors. Additional research is needed to explore occurrence of Raynaud's phenomenon in participants treated with gepants, as it has been associated with CGRP monoclonal antibodies, but are not extensively studied in gepants. Gepants are expected to play a significant role in the next generation of migraine treatments.

Hydrodynamic Diversity of Jets Mediated by Giant and Non-Giant Axon Systems in Brief Squid.

Neural input is critical for establishing behavioral output, but understanding how neuromuscular signals give rise to behaviors remains a challenge. In squid, locomotion through jet propulsion underlies many key behaviors, and the jet is mediated by two parallel neural pathways, the giant and non-giant axon systems. Much work has been done on the impact of these two systems on jet kinematics, such as mantle muscle contraction and pressure-derived jet speed at the funnel aperture. However, little is known about any influence these neural pathways may have on the hydrodynamics of the jet after it leaves the squid and transfers momentum to the surrounding fluid for the animal to swim. To gain a more comprehensive view of squid jet propulsion, we made simultaneous measurements of neural activity, pressure inside the mantle cavity, and wake structure. By computing impulse and time-averaged forces from the wake structures of jets associated with giant or non-giant axon activity, we show that the influence of neural pathways on jet kinematics could extend to hydrodynamic impulse and force production. Specifically, the giant axon system produced jets with, on average, greater impulse magnitude than those of the non-giant system. However, non-giant impulse could exceed that of the giant system, evident by the graded range of its output in contrast to the stereotyped nature of the giant system. Our results suggest that the non-giant system offers flexibility in hydrodynamic output, while recruitment of giant axon activity can provide a reliable boost when necessary.

Impact of specialty pharmacy collaboration with rheumatology clinics to improve the achievement of treat-to-target goals in patients with rheumatoid arthritis: a pilot study.

In rheumatoid arthritis, the use of Routine Assessment of Patient Index Data 3 (RAPID3) assessments to meet treat-to-target goals is endorsed by the 2021 American College of Rheumatology guidelines. In November 2020, the Baylor Scott & White specialty pharmacy implemented a new service that included more frequent collection of RAPID3 scores and standardized provider communication for patients co-managed by a Baylor Scott & White rheumatology clinic. The objective was to evaluate the impact of this new service on rheumatoid arthritis disease activity. Before the new service started, patients followed a protocol of RAPID3 assessments that occurred every 6 months; once the service began, patients were followed using an algorithm in which patients with higher disease activity were contacted more frequently. Eighty-six percent of patients in the pre-intervention group (n = 7) compared with 100% of patients in the post-intervention group (n = 10) had high to moderate disease activity at baseline. Within a 6-month follow-up period in both groups, the percentage of high to moderate disease activity patients decreased by 30% in the post-intervention group and remained the same in the pre-intervention group. These results support the positive impact increased specialty pharmacy services may have on clinical outcomes; therefore, the continued expansion of these services should be considered.

The intestine is a major contributor to circulating succinate in mice.

The tricarboxylic acid (TCA) cycle is the epicenter of cellular aerobic metabolism. TCA cycle intermediates facilitate energy production and provide anabolic precursors, but also function as intra- and extracellular metabolic signals regulating pleiotropic biological processes. Despite the importance of circulating TCA cycle metabolites as signaling molecules, the source of circulating TCA cycle intermediates remains uncertain. We observe that in mice, the concentration of TCA cycle intermediates in the portal blood exceeds that in tail blood indicating that the gut is a major contributor to circulating TCA cycle metabolites. With a focus on succinate as a representative of a TCA cycle intermediate with signaling activities and using a combination of gut microbiota depletion mouse models and isotopomer tracing, we demonstrate that intestinal microbiota is not a major contributor to circulating succinate. Moreover, we demonstrate that endogenous succinate production is markedly higher than intestinal succinate absorption in normal physiological conditions. Altogether, these results indicate that endogenous succinate production within the intestinal tissue is a major physiological source of circulating succinate. These results provide a foundation for an investigation into the role of the intestine in regulating circulating TCA cycle metabolites and their potential signaling effects on health and disease.

Glucagon-receptor-antagonism-mediated ß-cell regeneration as an effective anti-diabetic therapy.

Type 1 diabetes mellitus (T1D) is a chronic disease with potentially severe complications, and ß-cell deficiency underlies this disease. Despite active research, no therapy to date has been able to induce ß-cell regeneration in humans. Here, we discover the ß-cell regenerative effects of glucagon receptor antibody (anti-GcgR). Treatment with anti-GcgR in mouse models of ß-cell deficiency leads to reversal of hyperglycemia, increase in plasma insulin levels, and restoration of ß-cell mass. We demonstrate that both ß-cell proliferation and α- to ß-cell transdifferentiation contribute to anti-GcgR-induced ß-cell regeneration. Interestingly, anti-GcgR-induced α-cell hyperplasia can be uncoupled from ß-cell regeneration after antibody clearance from the body. Importantly, we are able to show that anti-GcgR-induced ß-cell regeneration is also observed in non-human primates. Furthermore, anti-GcgR and anti-CD3 combination therapy reverses diabetes and increases ß-cell mass in a mouse model of autoimmune diabetes.

Making sense of mRNA landscapes: Translation control in neurodevelopment.

Like all other parts of the central nervous system, the mammalian neocortex undergoes temporally ordered set of developmental events, including proliferation, differentiation, migration, cellular identity, synaptogenesis, connectivity formation, and plasticity changes. These neurodevelopmental mechanisms have been characterized by studies focused on transcriptional control. Recent findings, however, have shown that the spatiotemporal regulation of post-transcriptional steps like alternative splicing, mRNA traffic/localization, mRNA stability/decay, and finally repression/derepression of protein synthesis (mRNA translation) have become just as central to the neurodevelopment as transcriptional control. A number of dynamic players act post-transcriptionally in the neocortex to regulate these steps, as RNA binding proteins (RBPs), ribosomal proteins (RPs), long non-coding RNAs, and/or microRNA. Remarkably, mutations in these post-transcriptional regulators have been associated with neurodevelopmental, neurodegenerative, inherited, or often co-morbid disorders, such as microcephaly, autism, epilepsy, intellectual disability, white matter diseases, Rett-syndrome like phenotype, spinocerebellar ataxia, and amyotrophic lateral sclerosis. Here, we focus on the current state, advanced methodologies and pitfalls of this exciting and upcoming field of RNA metabolism with vast potential in understanding fundamental neurodevelopmental processes and pathologies. This article is categorized under: Translation > Translation Regulation RNA in Disease and Development > RNA in Disease RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.

Malignancies diagnosed before and after anal squamous cell carcinomas: A SEER registry analysis.

BACKGROUND: Increased risk of a second primary malignancy (SPM) before or after diagnosis of anal squamous cell carcinoma (ASCC) has been reported in a previous single-institution study. We hypothesize that patients diagnosed with ASCC are at increased risk for developing SPMs before or after the diagnosis of ASCC. The primary objective of this study was to identify the diagnoses of cancer most likely to occur as SPMs before or after ASCC. METHODS: This work employs the Surveillance, Epidemiology, and End Results (SEER) Program registry data to conduct a US-population-based study of patients diagnosed with ASCC between 1975 and 2016. In patients diagnosed with ASCC, we evaluated the risk of SPMs and the risk of developing ASCC as an SPM after another cancer using standardized incidence ratios (SIR) for all SPMs by calculating the ratio of observed events in the ASCC cohort compared to expected (O/E) events in a matched reference cohort of the general population. RESULTS: A total of 7,594 patients with primary ASCC were included. Patients with ASCC were at increased risk of the diagnosis of an SPM (SIR = 1.45), particularly cancers of the lung, vulva, oropharynx, or colon. Patients with ASCC had an increased rate of previous malignancy (SIR = 1.23), especially Kaposi sarcoma or vulvar cancer. Overall elevated incidence of SPMs was unrelated to prior radiation treatment. Radiation treatment was associated with increased risk for SPMs in the female genital system but appeared protective against prostate cancer as SPMs. CONCLUSIONS: Our findings support increased surveillance and screening for second malignancies in patients with these diagnoses, as patients with ASCC are often either survivors of a prior cancer diagnosis or are at increased risk of developing later malignancies.

Extrinsic Regulators of mRNA Translation in Developing Brain: Story of WNTs.

Extrinsic molecules such as morphogens can regulate timed mRNA translation events in developing neurons. In particular, Wingless-type MMTV integration site family, member 3 (Wnt3), was shown to regulate the translation of Foxp2 mRNA encoding a Forkhead transcription factor P2 in the neocortex. However, the Wnt receptor that possibly mediates these translation events remains unknown. Here, we report Frizzled member 7 (Fzd7) as the Wnt3 receptor that lays downstream in Wnt3-regulated mRNA translation. Fzd7 proteins co-localize with Wnt3 ligands in developing neocortices. In addition, the Fzd7 proteins overlap in layer-specific neuronal subpopulations expressing different transcription factors, Foxp1 and Foxp2. When Fzd7 was silenced, we found decreased Foxp2 protein expression and increased Foxp1 protein expression, respectively. The Fzd7 silencing also disrupted the migration of neocortical glutamatergic neurons. In contrast, Fzd7 overexpression reversed the pattern of migratory defects and Foxp protein expression that we found in the Fzd7 silencing. We further discovered that Fzd7 is required for Wnt3-induced Foxp2 mRNA translation. Surprisingly, we also determined that the Fzd7 suppression of Foxp1 protein expression is not Wnt3 dependent. In conclusion, it is exhibited that the interaction between Wnt3 and Fzd7 regulates neuronal identity and the Fzd7 receptor functions as a downstream factor in ligand Wnt3 signaling for mRNA translation. In particular, the Wnt3-Fzd7 signaling axis determines the deep layer Foxp2-expressing neurons of developing neocortices. Our findings also suggest that Fzd7 controls the balance of the expression for Foxp transcription factors in developing neocortical neurons. These discoveries are presented in our manuscript within a larger framework of this review on the role of extrinsic factors in regulating mRNA translation.

A phytic acid analogue INS-3001 prevents ectopic calcification in an Abcc6-/- mouse model of pseudoxanthoma elasticum.

Pseudoxanthoma elasticum (PXE), a prototype of heritable ectopic calcification disorders, affects the skin, eyes and the cardiovascular system due to inactivating mutations in the ABCC6 gene. There is no effective treatment for the systemic manifestations of PXE. In this study, the efficacy of INS-3001, an analogue of phytic acid, was tested for inhibition of ectopic calcification in an Abcc6-/- mouse model of PXE. In prevention study, Abcc6-/- mice, at 6 weeks of age, the time of onset of ectopic calcification, were treated with INS-3001 with 0.16, 0.8, 4, 20 or 100 mg/kg/day administered by subcutaneous implantation of osmotic pumps, as well as 4 mg/kg/day by subcutaneous injection thrice weekly or 14, 4 and 0.8 mg/kg/day once weekly subcutaneous injection. Mice were necropsied at 12 weeks of age. Histologic examination and quantitative calcium assay revealed that mice receiving 6 weeks of continuous INS-3001 administration via osmotic pumps showed dose-dependent inhibition of muzzle skin calcification with complete response at 4 mg/kg/day and a minimum effective dose at 0.8 mg/kg/day. INS-3001 plasma concentrations were dose-dependent and largely consistent during treatment for each dose. thrice weekly and once weekly subcutaneous injections of INS-3001 also prevented calcification. In established disease study, 12-week-old Abcc6-/- mice with extensive calcification were continuously administered INS-3001 at 4 mg/kg/day for a follow-up of 12 weeks. INS-3001 treatment was found to stabilize existing calcification that had developed at start of treatment. These results suggest that INS-3001 may provide a promising preventive treatment strategy for PXE, a currently intractable ectopic calcification disorder.

Antibody-mediated inhibition of GDF15-GFRAL activity reverses cancer cachexia in mice.

Cancer cachexia is a highly prevalent condition associated with poor quality of life and reduced survival1. Tumor-induced perturbations in the endocrine, immune and nervous systems drive anorexia and catabolic changes in adipose tissue and skeletal muscle, hallmarks of cancer cachexia2-4. However, the molecular mechanisms driving cachexia remain poorly defined, and there are currently no approved drugs for the condition. Elevation in circulating growth differentiation factor 15 (GDF15) correlates with cachexia and reduced survival in patients with cancer5-8, and a GDNF family receptor alpha like (GFRAL)-Ret proto-oncogene (RET) signaling complex in brainstem neurons that mediates GDF15-induced weight loss in mice has recently been described9-12. Here we report a therapeutic antagonistic monoclonal antibody, 3P10, that targets GFRAL and inhibits RET signaling by preventing the GDF15-driven interaction of RET with GFRAL on the cell surface. Treatment with 3P10 reverses excessive lipid oxidation in tumor-bearing mice and prevents cancer cachexia, even under calorie-restricted conditions. Mechanistically, activation of the GFRAL-RET pathway induces expression of genes involved in lipid metabolism in adipose tissues, and both peripheral chemical sympathectomy and loss of adipose triglyceride lipase protect mice from GDF15-induced weight loss. These data uncover a peripheral sympathetic axis by which GDF15 elicits a lipolytic response in adipose tissue independently of anorexia, leading to reduced adipose and muscle mass and function in tumor-bearing mice.

Translational derepression of Elavl4 isoforms at their alternative 5' UTRs determines neuronal development.

Neurodevelopment requires precise regulation of gene expression, including post-transcriptional regulatory events such as alternative splicing and mRNA translation. However, translational regulation of specific isoforms during neurodevelopment and the mechanisms behind it remain unknown. Using RNA-seq analysis of mouse neocortical polysomes, here we report translationally repressed and derepressed mRNA isoforms during neocortical neurogenesis whose orthologs include risk genes for neurodevelopmental disorders. We demonstrate that the translation of distinct mRNA isoforms of the RNA binding protein (RBP), Elavl4, in radial glia progenitors and early neurons depends on its alternative 5' UTRs. Furthermore, 5' UTR-driven Elavl4 isoform-specific translation depends on upstream control by another RBP, Celf1. Celf1 regulation of Elavl4 translation dictates development of glutamatergic neurons. Our findings reveal a dynamic interplay between distinct RBPs and alternative 5' UTRs in neuronal development and underscore the risk of post-transcriptional dysregulation in co-occurring neurodevelopmental disorders.

Patient and provider characteristics and outcomes associated with outpatient antibiotic overuse in acute adult bronchitis.

Nonbacterial acute bronchitis leads to many outpatient clinic visits in the US that result in an antibiotic prescription. Understanding antibiotic prescribing patterns and their clinical consequences will help improve antimicrobial stewardship efforts. A retrospective chart review was conducted to identify any correlations between patient and provider characteristics with antibiotic use in adult acute bronchitis (AAB) and to compare the clinical outcomes and rates of health care utilization between those who did and did not receive antibiotics. Study participants included adults with uncomplicated AAB seen by family medicine or internal medicine, specialty, and mid-level practitioners in a Baylor Scott & White Health outpatient facility. Phase 1 investigated whether prescribing rates varied by provider- or patient-level characteristics. Phase 2 compared clinical outcomes and health care utilization between patients who received an antibiotic versus those who did not receive an antibiotic for AAB. Among 35,383 visits for AAB, 81.4% resulted in a prescription for an antibiotic. Physicians >35 years of age and internal and family medicine physicians were more likely to prescribe antibiotics. Health care utilization rates did not differ between cohorts. The number of Clostridium difficile events was negligible.

Prevalence and Longevity of PTSD Symptoms Among Parents of NICU Infants Analyzed Across Gestational Age Categories.

Objective. This study aims to investigate whether posttraumatic stress disorder (PTSD) symptoms exist >1 year after neonatal intensive care unit (NICU) experience and whether PTSD symptomatology differs across parents of infants of different gestational age categories. Methods. A survey was given to parents at routine NICU follow-up visits. Parents completed the PTSD CheckList-Civilian (PCL-C), a standardized scale comprising 17 key symptoms of PTSD. Parents also rated how traumatic their birth experience, first day in the NICU, and first week in the NICU were from "Not Traumatic at All" to "Most Traumatic." Fisher's exact test was used to compare PCL-C responses across gestational age categories (Extremely Preterm, Very Preterm, Moderate to Late preterm, and Full Term). Results. Eighty parents participated. In total, 15% of parents had "Moderate to High Severity" PTSD symptoms. There were no statistical differences in PTSD prevalence between parents of children <1 year old and parents of children >1 year old (P = .51). There was also no statistical difference in prevalence of "Moderate to High Severity" level of PTSD symptoms across gestational age (P = .16). Overall, 38% of parents rated at least one experience as "Most traumatic." Conclusion. A high percentage of parents who had a recent NICU experience and parents who had a NICU experience more than a year ago demonstrated PTSD symptoms. In light of these results, many parents of NICU graduates-both mothers and fathers-would benefit from access to long-term counseling services.

Bisphenol A inhibits autophagosome-lysosome fusion and lipid droplet degradation.

Bisphenol A (BPA) is an artificial xenoestrogen widely used in consumer products containing polycarbonate plastics and epoxy resins. Exposure to BPA occurs through various channels, including ingestion of contaminated food and water. Autophagy is an important catabolic pathway that plays an important role in liver lipid metabolism. Evidence suggests that BPA exposure causes abnormal lipid droplet accumulation in liver, but the mechanism remains unknown. Here, we investigate the function of BPA in lipid metabolism and autophagy. BPA exposure increases lipid droplet and ROS accumulation which is accompanied by a defect in the fusion of the autophagosome to the lysosome. BPA exposure decreases the translocation of Stx17 to lysosome resulting in the autophagogome-lysosome fusion defect. There is no defect in the formation of the autophagosome indicated by increased LC3-II, p62 level, GFP/mRFP-LC3 ratios and decreased colocalization between LAMP2 with LC3. Mechanistically, BPA exposure reduces autophagy SNARE complex formation. Promoting autophagy by autophagy inducer (Torin2) partially reverses lipid droplet accumulation caused by BPA exposure. In summary, our results demonstrate BPA exposure inhibits autophagy resulting in decreased lipid droplet degradation and increased ROS levels. These results also provide a novel implication between autophagosome-lysosome fusion.

Synchronous Oligometastatic Non-small Cell Lung Cancer Managed With Curative-Intent Chemoradiation Therapy: Long-term Outcomes From a Single Institution.

PURPOSE: We examined long-term clinical outcomes among patients with synchronous oligometastatic non-small cell lung cancer (NSCLC) treated at our institution with definitive thoracic chemoradiation therapy (CRT) and local therapy to all oligometastatic lesions. METHODS AND MATERIALS: A retrospective review identified 38 patients with synchronous oligometastatic NSCLC (≤3 metastatic lesions) who were treated with definitive CRT to the primary tumor and regional lymph nodes between 1999 and 2017 at our institution. Of the 38 patients, 27 patients (71%) received induction chemotherapy, all of whom responded or stabilized with initial systemic therapy before consideration of CRT. Most patients received chemotherapy concurrently with radiation therapy (n = 32; 84%) and local therapy to the metastatic disease site(s) (n = 34; 89%). We assessed patterns of progression or failure, overall survival (OS), progression-free survival (PFS), and toxicities. RESULTS: The median follow-up duration was 54.9 months. Most patients (84%) presented with N2 to N3 disease. The brain or central nervous system was the most common site of disease progression and occurred in 16 of 28 patients (57%) experiencing any progression and 10 of 16 patients (63%) who initially presented with brain oligometastases. Median OS was 21.1 months (95% confidence interval [CI], 15.6-49.0 months), and median PFS 9.7 months (95% CI, 8.2-14.4 months). The 1-, 2-, and 4-year OS rates were 75.7%, 45.0%, and 33.7%, respectively. On multivariate analysis, both locoregional progression (hazard ratio: 5.8; 95% CI, 2.2-15.0; P = .0003) and distant progression (hazard ratio: 6.0; 95% CI, 2.3-15.4; P = .0002), when treated as time-dependent covariates, were associated with inferior OS. Grade ≥3 esophagitis occurred in 9% and grade ≥3 pneumonitis in 5% of patients with evaluable data. CONCLUSIONS: Patients with synchronous oligometastatic NSCLC and a high regional nodal burden treated with definitive thoracic CRT experienced favorable survival outcomes and low toxicity. At our institution, treating oligometastatic disease with CRT after systemic therapy is incorporated into the treatment plan from the onset of therapy, and we monitor the neuraxis closely for progression during and after treatment. Future research should focus on novel treatment combinations, such as immunotherapy or targeted systemic therapy as appropriate to further improve tumor control and survival.

Intestinal basolateral lipid substrate transport is linked to chylomicron secretion and is regulated by apoC-III.

Chylomicron metabolism is critical for determining plasma levels of triacylglycerols (TAGs) and cholesterol, both of which are risk factors for CVD. The rates of chylomicron secretion and remnant clearance are controlled by intracellular and extracellular factors, including apoC-III. We have previously shown that human apoC-III overexpression in mice (apoC-IIITg mice) decreases the rate of chylomicron secretion into lymph, as well as the TAG composition in chylomicrons. We now find that this decrease in chylomicron secretion is not due to the intracellular effects of apoC-III, but instead that primary murine enteroids are capable of taking up TAG from TAG-rich lipoproteins (TRLs) on their basolateral surface; and via Seahorse analyses, we find that mitochondrial respiration is induced by basolateral TRLs. Furthermore, TAG uptake into the enterocyte is inhibited when excess apoC-III is present on TRLs. In vivo, we find that dietary TAG is diverted from the cytosolic lipid droplets and driven toward mitochondrial FA oxidation when plasma apoC-III is high (or when basolateral substrates are absent). We propose that this pathway of basolateral lipid substrate transport (BLST) plays a physiologically relevant role in the maintenance of dietary lipid absorption and chylomicron secretion. Further, when apoC-III is in excess, it inhibits BLST and chylomicron secretion.

Hypoxia tolerance of giant axon-mediated escape jetting in California market squid (Doryteuthis opalescens).

Squids display a wide range of swimming behaviors, including powerful escape jets mediated by the giant axon system. For California market squid (Doryteuthis opalescens), maintaining essential behaviors like the escape response during environmental variations poses a major challenge as this species often encounters intrusions of cold, hypoxic offshore waters in its coastal spawning habitats. To explore the effects of hypoxia on locomotion and the underlying neural mechanisms, we made in vivo recordings of giant axon activity and simultaneous pressure inside the mantle cavity during escape jets in squid exposed to acute progressive hypoxia followed by return to normal dissolved oxygen (DO) concentration (normoxia). Compared with those in normoxia (>8 mg l-1 DO), escape jets were unchanged in moderate hypoxia (4 and 2 mg l-1 DO), but giant axon activity and associated mantle contractions significantly decreased while neuromuscular latency increased under severe hypoxia (0.5 mg l-1 DO). Animals that survived exposure to severe hypoxia reliably produced escape jets under such conditions and fully recovered as more oxygen became available. The reduction in neuromuscular output under hypoxia suggests that market squid may suppress metabolic activity to maintain sufficient behavioral output, a common strategy in many hypoxia-tolerant species. The ability to recover from the deleterious effects of hypoxia suggests that this species is well adapted to cope with coastal hypoxic events that commonly occur in Monterey Bay, unless these events become more severe in the future as climate change progresses.

The Isolation, Culture, and Propagation of Murine Intestinal Enteroids for the Study of Dietary Lipid Metabolism.

Since the initial report in 2009 by Sato and Clevers, primary enteroids have been of major interest in the fields of stem cell biology and gastrointestinal (GI) tract biology. More recently, we and others have made major inroads into the physiological relevance of these enteroid models and have shown that enteroids derived from the stomach, intestine, or colon recapitulate major functions of these tissues, namely, gastric acid secretion, lipid absorption and lipoprotein secretion, and ion transport. Here, we detail the isolation of stem cells from the small intestine and the culture and propagation of those stem cells into mature three-dimensional enteroids. We will also detail how we use enteroids to determine intestinal mechanisms behind dietary lipid absorption and lipoprotein secretion. The primary enteroid model is a powerful tool that significantly expands our ability to model GI tract function in vitro.