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An ecologically and economically disruptive harmful algal bloom (HAB) affected much of the northeast Pacific margin in 2015, during a prolonged oceanic warm anomaly. Caused by diatoms of the genus Pseudo-nitzschia, this HAB produced the highest particulate concentrations of the biotoxin domoic acid (DA) ever recorded in Monterey Bay, California. Bloom inception followed strong upwelling during the spring transition, which introduced nutrients and eliminated the warm anomaly locally. Subsequently, moderate and intermittent upwelling created favorable conditions for growth and accumulation of HAB biomass, which was dominated by a highly toxigenic species, P. australis. High cellular DA concentrations were associated with available nitrogen for DA synthesis coincident with silicate exhaustion. This nutrient influence resulted from two factors: (1) disproportionate depletion of silicate in upwelling source waters during the warm anomaly, the most severe depletion observed in 24 years, and (2) silicate uptake by the dense diatom bloom.

The purpose of this study was to determine if pre-exercise glucose ingestion would improve distance swimming performance. Additionally, pre-exercise glucose was provided at 2 different feeding intervals to investigate the affects of the timing of administration. Ten male triathletes (X +/- SD: age, 29.5 +/- 5.0 years; VO2peak, 48.8 +/- 3.2 ml x kg[-1] x min[-1]) swam 4000 m on 3 occasions following the consumption of either a 10% glucose solution 5 min prior to exercise (G[5]), a 10% glucose solution 35 min prior to exercise (G[35]), or a similar volume of placebo (PL). Despite a significant difference (p < .01) in blood glucose concentration prior to exercise (X +/- SD in mmol x L[-1]: G[35] 8.4 +/- 1.1 vs. G[5] 5.2 +/- 0.5 or PL 5.3 +/- 0.4), no significant differences were observed in total time (X +/- SD in minutes: G[35] 70.7 +/- 7.6, G[5] 70.1 +/- 7.6, PL 71.9 +/- 8.4), post-exercise blood glucose (X +/- SD in mmol x L[-1]: G[35] 5.1 +/- 1.1, G[5] 5.1 +/- 0.9, PL 5.3 +/- 0.4), and average heart rate (X +/- SD in bpm: G[35] 155.8 +/- 10.8, G[5] 153.6 +/- 12.6, PL 152.0 +/- 12.5; p > .05). While not reaching statistical significance, glucose feedings did result in improved individual performance times, ranging from 24 s to 5 min in 8 of the 10 subjects compared to the placebo. These results were found despite significant differences in blood glucose between trials immediately prior to exercise. [ABSTRACT FROM AUTHOR]

The Dunning H rat prostate tumor (R3327H) is a widely used experimental model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been characterized as androgen-sensitive, androgen-receptor (AR) positive, prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To date, the tumor has been maintained by serial passage in vivo because of the lack of an in vitro cell line that retains the characteristics of the in vivo tumor. The objective of the present study was to establish a propagable cell line from R3327H adenocarcinoma that maintained androgen sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in vivo R3327H tumor was dissociated with collagenase and placed into Richter's improved media (with supplements). A cytokeratin-positive epithelial cell line (HUNC-E) and a vimentin-positive stromal cell line (HUNC-S) were generated from the primary culture, subcultured continuously for >300 days, and passaged >50 times. Survival of the HUNC-E cell line in vitro depended on several media supplements, including nicotinamide, insulin, transferrin, selenium and epidermal growth factor (EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the culture period, as confirmed by immunocytochemistry and Western blot analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT) to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent growth and PSA production, which demonstrated the androgen-sensitive nature of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1 ratio and introduced subcutaneously into syngeneic male hosts, tumors formed in 2/3 animals with an average latency of 7 months. RT-PCR and immunocytochemical characterization of the HUNC cell lines revealed that the cells expressed several growth factors and their cognate receptors, including HGF, TGF-α and the TGF-βs, indicating the establishment of potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S CaP cell lines, which retain the characteristics of the epithelial and stromal components of the in vivo R3327H tumor, will allow a more thorough and informative molecular and biological analysis of prostatic adenocarcinoma. [ABSTRACT FROM PUBLISHER]

In 2015, the largest recorded harmful algal bloom (HAB) occurred in the Northeast Pacific, causing nearly 100 million dollars in damages to fisheries and killing many protected marine mammals. Dominated by the toxic diatom Pseudo-nitzschia australis , this bloom produced high levels of the neurotoxin domoic acid (DA). Through molecular and transcriptional characterization of 52 near-weekly phytoplankton net-tow samples collected at a bloom hotspot in Monterey Bay, California, we identified active transcription of known DA biosynthesis ( dab ) genes from the three identified toxigenic species, including P. australis as the primary origin of toxicity. Elevated expression of silicon transporters ( sit1 ) during the bloom supports the previously hypothesized role of dissolved silica (Si) exhaustion in contributing to bloom physiology and toxicity. We find that coexpression of the dabA and sit1 genes serves as a robust predictor of DA one week in advance, potentially enabling the forecasting of DA-producing HABs. We additionally present evidence that low levels of iron could have colimited the diatom population along with low Si. Iron limitation represents an overlooked driver of both toxin production and ecological success of the low-iron-adapted Pseudo-nitzschia genus during the 2015 bloom, and increasing pervasiveness of iron limitation may fuel the escalating magnitude and frequency of toxic Pseudo-nitzschia blooms globally. Our results advance understanding of bloom physiology underlying toxin production, bloom prediction, and the impact of global change on toxic blooms., Competing Interests: Competing interests statement:The authors declare no competing interest.

Objective: Continuous glucose monitoring (CGM) can detect early dysglycemia in older children and adults with presymptomatic type 1 diabetes (T1D) and predict risk of progression to clinical onset. However, CGM data for very young children at greatest risk of disease progression are lacking. This study aimed to investigate the use of CGM data measured in children being longitudinally observed in the Australian Environmental Determinants of Islet Autoimmunity (ENDIA) study from birth to age 10 years., Research Design and Methods: Between January 2021 and June 2023, 31 ENDIA children with persistent multiple islet autoimmunity (PM Ab+) and 24 age-matched control children underwent CGM assessment alongside standard clinical monitoring. The CGM metrics of glucose SD (SDSGL), coefficient of variation (CEV), mean sensor glucose (SGL), and percentage of time >7.8 mmol/L (>140 mg/dL) were determined and examined for between-group differences., Results: The mean (SD) ages of PM Ab+ and Ab- children were 4.4 (1.8) and 4.7 (1.9) years, respectively. Eighty-six percent of eligible PM Ab+ children consented to CGM wear, achieving a median (quartile 1 [Q1], Q3) sensor wear period of 12.5 (9.0, 15.0) days. PM Ab+ children had higher median (Q1, Q3) SDSGL (1.1 [0.9, 1.3] vs. 0.9 [0.8, 1.0] mmol/L; P < 0.001) and CEV (17.3% [16.0, 20.9] vs. 14.7% [12.9, 16.6]; P < 0.001). Percentage of time >7.8 mmol/L was greater in PM Ab+ children (median [Q1, Q3] 8.0% [4.4, 13.0] compared with 3.3% [1.4, 5.3] in Ab- children; P = 0.005). Mean SGL did not differ significantly between groups (P = 0.10)., Conclusions: CGM is feasible and well tolerated in very young children at risk of T1D. Very young PM Ab+ children have increased SDSGL, CEV, and percentage of time >7.8 mmol/L, consistent with prior studies involving older participants., (© 2024 by the American Diabetes Association.)

Objective: To determine the efficacy of advanced hybrid closed loop (AHCL) therapy in a high-risk cohort of youth on continuous subcutaneous insulin infusion (CSII) ± continuous glucose monitoring (CGM) with suboptimal glycemia., Research Design and Methods: In a 6-month multicenter clinical trial, youth with type 1 diabetes with mean and most recent HbA1c > 8.5% (65 mmol/mol) were randomly assigned 1:1 to AHCL or treatment as usual (CSII ± CGM). The primary outcome was the 24-week between-group difference in HbA1c. Secondary outcomes included CGM metrics from masked CGM and psychological measures (youth-reported problem areas in diabetes [PAID], quality of life, anxiety, depression, and hypoglycemia fear) assessed using validated questionnaires., Results: A total of 42 participants were randomized (mean [SD] age 16.2 [2.5] years, HbA1c 9.8 [1.1]% or 84 [12] mmol/mol, PAID score 50.3 [19.8]). At study end, the mean (SD) HbA1c was 8.8 (1.1)% or 73 (12) mmol/mol with AHCL and 9.9 (1.2)% or 85 (13.1) mmol/mol with CSII ± CGM, with mean adjusted group difference of -0.77% (95% CI -1.45 to -0.09) or -8.4 mmol/mol (-15.8 to -1.0); P = 0.027. AHCL increased time in range 70-180 mg/dL (difference 19.1%; 95% CI 11.1 to 27.1), reduced time >180 mg/dL (difference -17.7%; 95% CI -26.6 to -8.8), with no increase in time spent <70 mg/dL (difference -0.8%; 95% CI -2.7 to 0.6). There was no evidence for difference in psychosocial outcomes between the two groups at study end., Conclusions: AHCL should be encouraged in youth with suboptimal glycemia, as AHCL improves glycemia. However, psychological support remains vital, as technology alone may not be able to reduce the burden of diabetes care in this subgroup., (© 2024 by the American Diabetes Association.)