Gut Microbes Reveal Pseudomonas Medicates Ingestion Preference via Protein Utilization and Cellular Homeostasis Under Feed Domestication in Freshwater Drum, Aplodinotus grunniens

With strong demand for aquatic products, as well as a rapid decrease in global fishery resources and capture fisheries, domesticating animals to provide more high-quality proteins is meaningful for humans. Freshwater drum (Aplodinotus grunniens) is widely distributed in the wild habitats of North America. However, the research on A. grunniens and the feed domestication with diets composed of artificial compounds remains unclear. In this study, a 4-month feeding domestication experiment was conducted with A. grunniens larvae to evaluate the underlying mechanism and molecular targets responsible for alternations in the ingestion performance. The results indicated that a significant increase in the final body weight was exhibited by the feed domesticated group (DOM, 114.8 g) when compared to the group that did not ingest the feed (WT, 5.3 g) as the latest version we raised From the result, the final body weight exhibited significant increase between unfavorable with the feed (WT, 5.3 g) and feed domesticated group (DOM, 114.8 g). In addition, the enzyme activity of digestive enzymes like amylase, lipase, and trypsin was increased in DOM. Genes related to appetite and perception, such as NPY4R, PYY, and LEPR, were activated in DOM. 16s rRNA gene sequencing analysis revealed that Pseudomonas sp. increased from 58.74% to 89.77% in DOM, which accounts for the dominant upregulated microbial community at the genus level, followed by Plesiomonas. Analogously, Mycobacterium, Methylocystis, and Romboutsia also accounted for the down-regulated microbes in the diversity. Transcriptome and RT-PCR analysis revealed that feed domestication significantly improved protein digestion and absorption, inhibited apoptosis by AGE-RAGE signaling, and activated extracellular matrix remodeling by relaxin signaling. Integrated analysis of the microbiome and host transcriptome revealed that Pseudomonas-mediated ingestion capacity, protein utilization, and cellular homeostasis might be the underlying mechanism under feed domestication. These results indicate Pseudomonas and its key genes relating to food ingestion and digestion could serve as the molecular targets for feed domestication and sustainable development in A. grunniens

Highly toughened polylactide with novel sliding graft copolymer by in situ reactive compatibilization, crosslinking and chain extension

YesThe “sliding graft copolymer” (SGC), in which many linear poly-ε-caprolactone (PCL) side chains are bound to cyclodextrin rings of a polyrotaxane (PR), was prepared and employed to toughen brittle polylactide (PLA) with methylene diphenyl diisocyanate (MDI) by reactive blending. The SGC was in situ crosslinked and therefore transformed from a crystallized plastic into a totally amorphous elastomer during reactive blending. Meanwhile, PLA-co-SGC copolymer was formed at interface to greatly improve the compatibility between PLA and SGC, and the chain extension of PLA also occurred, were confirmed by FTIR, GPC, SEM, and TEM. The resulting PLA/SGC/MDI blends displayed super impact toughness, elongation at break and nice biocompatibility. It was inferred from these results the crosslinked SGC (c-SGC) elastomeric particles with sliding crosslinking points performed as stress concentrators and absorbed considerable energy under impact and tension process.This work was supported by the National Natural Science Foundation of China (50933001, 51221002 and 51320105012)

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Role of NHE3 in the intestine and thick ascending limb of the kidneys

The sodium-hydrogen exchanger isoform 3 (NHE3, SLC9A3) mediates most Na+/H+ exchange in the gastrointestinal tract and the kidney, where it plays crucial roles in Na+ and fluid absorption as well as acid-base homeostasis. Whole body NHE3 knockout (NHE3-/-) mice show overt absorptive defects in both the intestine and kidneys. Genetic mutations of NHE3 gene in humans are associated with congenital sodium diarrhea (CSD). In the kidneys, NHE3 is expressed in the proximal tubule (PT) and the thick ascending limb (TAL). Whole kidney-specific (PT and TAL) NHE3 knockout (NHE3Pax8cre) mice and PT-specific NHE3 knockout (PT-NHE3-/-) mice have shown the importance of renal NHE3 in Na+ homeostasis and blood pressure regulation. To date, the relative contribution of NHE3 in the intestine versus the kidneys and the role of NHE3 in the TAL for Na+, fluid and acid-base homeostasis not been selectively investigated due to a lack of suitable animal models. To fill these two knowledge gaps, two series of experiment were conducted by using novel tamoxifen inducible intestinal epithelial cell specific (NHE3IEC-KO) and TAL-specific NHE3 knockout (NHE3TAL-KO) mouse models. 1) No difference was found in blood parameters or other phenotypes between NHE3IEC-KO and control (NHE3loxlox) mice before tamoxifen administration. After tamoxifen administration, NHE3 was completely deleted in the intestine of NHE3IEC-KO mice. Loss of NHE3 causes defective intestinal absorption, indicated by watery, alkaline diarrhea and dilated intestine associated with a compensatory higher fluid intake in HE3IEC-KO mice. Three weeks after tamoxifen, ~25% mortality rate is found in NHE3IEC-KO mice. NHE3IEC-KO mice also show metabolic acidosis, lower blood bicarbonate levels, hyponatremia and hyperkalemia in combination with drastically elevated plasma aldosterone levels. These results indicate that intestinal NHE3 plays a significant role in acid-base, Na+ and volume homeostasis. This NHE3IEC-KO mouse model provides a suitable tool for studying the role of intestinal NHE3 and explains the phenotype of individuals with CSD carrying SLC9A3 mutations. 2) After tamoxifen administration, deletion of NHE3 in the TAL was confirmed by mRNA expression and immunofluorescent staining. Two weeks after tamoxifen administration, NHE3TAL-KO mice showed a ~25% lower urine osmolality associated with ~20% higher water intake compared to Con mice. No differences were found in blood pH, urinary pH, urinary Na+ or Cl-/creatinine ratios or glomerular filtration rate. Of note, NHE3TAL-KO mice have a higher K+/creatinine ratio compared to control mice. To test for a role of the TAL in urinary acidification we used furosemide which stimulates urinary acidification. In response to furosemide no dose-dependent differences were observed in Cl- excretion or urinary flow rate. Of note, NHE3TAL-KO mice showed an acute decrease in urinary pH similar to control mice followed by an immediate recovery of urinary pH, the latter completely absent in control mice. Taken together, the results indicate that NHE3 in the TAL contributes to urinary concentrating ability and the sustained response of the TAL to furosemide-induced urinary acidification. The new NHE3TAL-KO mouse model provides a useful tool to delineate the specific role of NHE3 in the TAL for renal functions. This thesis provides unprecedent insights into the functions of NHE3 in the intestine and TAL of the kidneys

Role of NHE3 in the intestine and thick ascending limb of the kidneys

The sodium-hydrogen exchanger isoform 3 (NHE3, SLC9A3) mediates most Na+/H+ exchange in the gastrointestinal tract and the kidney, where it plays crucial roles in Na+ and fluid absorption as well as acid-base homeostasis. Whole body NHE3 knockout (NHE3-/-) mice show overt absorptive defects in both the intestine and kidneys. Genetic mutations of NHE3 gene in humans are associated with congenital sodium diarrhea (CSD). In the kidneys, NHE3 is expressed in the proximal tubule (PT) and the thick ascending limb (TAL). Whole kidney-specific (PT and TAL) NHE3 knockout (NHE3Pax8cre) mice and PT-specific NHE3 knockout (PT-NHE3-/-) mice have shown the importance of renal NHE3 in Na+ homeostasis and blood pressure regulation. To date, the relative contribution of NHE3 in the intestine versus the kidneys and the role of NHE3 in the TAL for Na+, fluid and acid-base homeostasis not been selectively investigated due to a lack of suitable animal models. To fill these two knowledge gaps, two series of experiment were conducted by using novel tamoxifen inducible intestinal epithelial cell specific (NHE3IEC-KO) and TAL-specific NHE3 knockout (NHE3TAL-KO) mouse models. 1) No difference was found in blood parameters or other phenotypes between NHE3IEC-KO and control (NHE3loxlox) mice before tamoxifen administration. After tamoxifen administration, NHE3 was completely deleted in the intestine of NHE3IEC-KO mice. Loss of NHE3 causes defective intestinal absorption, indicated by watery, alkaline diarrhea and dilated intestine associated with a compensatory higher fluid intake in HE3IEC-KO mice. Three weeks after tamoxifen, ~25% mortality rate is found in NHE3IEC-KO mice. NHE3IEC-KO mice also show metabolic acidosis, lower blood bicarbonate levels, hyponatremia and hyperkalemia in combination with drastically elevated plasma aldosterone levels. These results indicate that intestinal NHE3 plays a significant role in acid-base, Na+ and volume homeostasis. This NHE3IEC-KO mouse model provides a suitable tool for studying the role of intestinal NHE3 and explains the phenotype of individuals with CSD carrying SLC9A3 mutations. 2) After tamoxifen administration, deletion of NHE3 in the TAL was confirmed by mRNA expression and immunofluorescent staining. Two weeks after tamoxifen administration, NHE3TAL-KO mice showed a ~25% lower urine osmolality associated with ~20% higher water intake compared to Con mice. No differences were found in blood pH, urinary pH, urinary Na+ or Cl-/creatinine ratios or glomerular filtration rate. Of note, NHE3TAL-KO mice have a higher K+/creatinine ratio compared to control mice. To test for a role of the TAL in urinary acidification we used furosemide which stimulates urinary acidification. In response to furosemide no dose-dependent differences were observed in Cl- excretion or urinary flow rate. Of note, NHE3TAL-KO mice showed an acute decrease in urinary pH similar to control mice followed by an immediate recovery of urinary pH, the latter completely absent in control mice. Taken together, the results indicate that NHE3 in the TAL contributes to urinary concentrating ability and the sustained response of the TAL to furosemide-induced urinary acidification. The new NHE3TAL-KO mouse model provides a useful tool to delineate the specific role of NHE3 in the TAL for renal functions. This thesis provides unprecedent insights into the functions of NHE3 in the intestine and TAL of the kidneys

Precision therapy for acute myeloid leukemia

Abstract Acute myeloid leukemia (AML) is a molecularly and clinically heterogeneous disease. Despite advances in understanding the pathogenesis of AML, the standard therapy remained nearly unchanged over the past three decades. With the poor survival for older patients and high relapse rate, multiple studies are ongoing to address this important issue. Novel therapies for AML, including the refinements of conventional cytotoxic chemotherapies and genetic and epigenetic targeted drugs, as well as immunotherapies, have been developed in recent years. Here, we present a mechanism-based review of some promising new drugs with clinical efficacy, focus on targeted drugs that are most potential to pave the road to success, and put forward the major challenges in promoting the precision therapy for AML

An Alignment Method for Strapdown Inertial Navigation Systems Assisted by Doppler Radar on a Vehicle-Borne Moving Base

In this study, we investigated a novel method for high-accuracy autonomous alignment of a strapdown inertial navigation system assisted by Doppler radar on a vehicle-borne moving base, which effectively avoids the measurement errors caused by wheel-slip or vehicle-sliding. Using the gyroscopes in a strapdown inertial navigation system and Doppler radar, we calculated the dead reckoning, analyzed the error sources of the dead reckoning system, and established an error model. Then the errors of the strapdown inertial navigation system and dead reckoning system were treated as the states. Besides velocity information, attitude information was cleverly introduced into the alignment measurement to improve alignment accuracy and reduce alignment time. Therefore, the first measurement was the difference between the output attitude and velocity of the strapdown inertial navigation system and the corresponding signals from the dead reckoning system. In order to further improve the alignment accuracy, more measurement information was introduced by using the vehicle motion constraint, that is, the velocity output projection of strapdown inertial navigation system along the transverse and vertical direction of the vehicle body was also used as the second measurement. Then the corresponding state and measurement equations were established, and the Kalman filter algorithm was used for assisted alignment filtering. The simulation results showed that, with a moving base, the misalignment angle estimation accuracy was better than 0.5’ in the east direction, 0.4’ in the north direction, and 3.2’ in the vertical direction