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Zou, H.

Publications and source records attributed to Zou, H..

At least 55 records · Page 3Linked to original sources

Early microbial intervention reduces diarrhea while improves later milk production in newborn calves

The rumen of neonatal calves is not well-developed and exhibits limited functionality. Therefore, the establishment of intestinal microbiota may play an instrumental role in their health and performance, but it has been rarely explored. Thus, we aim to explore the temporal colonization of the gut microbiome and the potential benefits of early microbial intervention in newborn calves. We followed up on the temporal dynamics of the gut microbiome and plasma metabolome in 36 newborn calves during the first two months of life and established their relationships with their health status and performance. We also evaluated whether microbiota transplantation (MT) could influence their phenotypes by modulating metabolism and its impact on later milk production performance.We showed that the composition and ecological interactions of the gut microbiome are likely to reach maturity one month after birth. Temporal changes in the gut microbiome of newborn calves are widely associated with changes in their physiological statuses, such as growth and fiber digestion. Importantly, we observed that MT reshapes the gut microbiome of newborns by altering the abundance and interaction of Bacteroides species, as well as amino acid pathways, such as arginine biosynthesis. Two-year follow-up of those calves further showed that MT improves their later milk production. Notably, MT improves fiber digestion, antioxidant capacity of newborns while reducing diarrhea. MT also contributes to significant changes in the metabolomic landscape, and with putative causal mediation analysis, we suggest that altered gut microbial composition in newborns may influence physiological status through microbial-derived metabolites. The data from the study may help develop strategies to manipulate the gut microbiota during early life, which may be significantly relevant to the health and production of newborn calves. HIGHLIGHTSO_LIThe gut microbial composition and ecological interaction in newborn calves reach maturity one month after birth C_LIO_LITemporal shifts in the gut microbiome of newborn calves are associated with phenotypic changes, including growth, digestion, and antioxidative capacity C_LIO_LIEarly microbial intervention in newborn calves reduces diarrhea while improving later milk production C_LIO_LIThe gut microbial impact on newborn calves is mediated by plasma metabolites C_LI

microbiology↗

Parasitism and locomotory capacity calibrate the mitogenomic evolutionary rates in Bilateria

The evidence that parasitic lineages exhibit elevated evolutionary rates is limited to Arthropoda and inconsistent. Similarly, the evidence that mitogenomic evolution is faster in species with low locomotory capacity (LC) is limited to a handful of animal lineages. We hypothesised that these two variables are associated and that LC is a major underlying factor driving the elevated evolutionary rates in parasites. We tested this hypothesis by studying mitogenomic evolutionary patterns in 10,911 bilaterian species classified according to their locomotory capacity and parasitic/free-living life history (LH). Evolutionary rates were significantly elevated in endoparasites, ectoparasites with reduced LC, and free-living lineages with reduced LC, but not in ectoparasites and parasitoids with high LC. Nematoda and Arachnida were the only lineages where parasitism was not associated with faster evolution. We propose that LC may also explain these two major outliers. Overall, the LH categorisation explained 35-37%, LC categorisation 26-28%, and together they explained 41-44% of the variance in branch lengths across the Bilateria. Our findings suggest that these two variables play a major role in calibrating the molecular clock in bilaterian animals.

evolutionary biology↗

Development of a human glioblastoma model using humanized DRAG mice for immunotherapy

Glioblastoma (GBM) is the most common and lethal primary brain tumor with high mortality rates and a short median survival rate of about 15 months despite intensive multimodal treatment of maximal surgical resection, radiotherapy, and chemotherapy. Although immunotherapies have been successful in the treatment of various cancers, disappointing results from clinical trials for GBM immunotherapy represent our incomplete understanding. The development of alternative humanized mouse models with fully functional human immune cells will potentially accelerate the progress of GBM immunotherapy. In this study, we developed a humanized DRAG (NOD.Rag1KO.IL2R{gamma}cKO) mouse model, in which the human hematopoietic stem cells (HSCs) were well-engrafted and subsequently differentiated into a full lineage of immune cells. Using this humanized DRAG mouse model, GBM patient-derived tumorsphere lines were successfully engrafted to form xenografted tumors, which can recapitulate the pathological features and the immune cell composition of human GBM. Importantly, the administration of anti-human PD-1 antibodies in these DRAG mice bearing a GBM patient-derived tumorsphere line resulted in decreasing the major tumor-infiltrating immunosuppressive cell populations, including CD4+PD-1+ and CD8+PD-1+ T cells, CD11b+CD14+HLA-DR+ macrophages, CD11b+CD14+HLA-DR-CD15- and CD11b+CD14- CD15+ myeloid-derived suppressor cells, indicating the humanized DRAG mouse model as a useful model to test the efficacy of immune checkpoint inhibitors in GBM immunotherapy. Together, these results suggest that humanized DRAG mouse models are a reliable preclinical platform for brain cancer immunotherapy and beyond.

cancer biology↗

Drivers of interlineage variability in mitogenomic evolutionary rates in flatworms (Platyhelminthes) are multifactorial

The forces driving interlineage variability in the evolutionary rates (both sequence and architecture) of mitochondrial genomes are often inconsistent and unpredictable. Herein we studied the impacts of multiple variables using 223 flatworm (Platyhelminthes) species and phylogenetic multilevel regression models. We found that: 1. Mitogenomic sequence evolution is faster in parasites associated with the thermally stable environment of endothermic hosts, but the overall impact of thermic habitat is small; 2. Mitogenome sizes are smaller in parasites of endothermic hosts, but the effects are small and inconsistent; 3. Mitogenomic gene order rearrangements (GORR) are positively correlated with mitogenomic size; 4. The expected positive correlation between GORR and sequence evolution is lineage-specific, and non-parasitic species exhibited a strong negative correlation; 5. Longevity has negligible impacts on mitogenomic evolution; 6. Parasitic (Neodermata) flatworm lineages exhibit higher evolutionary rates than non-parasitic lineages; 7. The effective population size has negligible impacts on mitogenomic evolution; 8. Comparatively, parasitism had by far the greatest impact on the mitogenomic evolution, but due to the monophyletic origin of this life-history strategy, alternative hypotheses cannot be rejected. A large number of factors impact the mitogenomic evolution in flatworms, with lineage-specific relative contributions, which sometimes produces incongruent lineage-specific mitogenomic evolution patterns.

evolutionary biology↗

Ralstonia solanacearum effector RipAF1 ADP-ribosylates host FBN1 to induce resistance against bacterial wilt

Ralstonia solanacearum (Rso) causes destructive bacterial wilt across a broad range of host plants by inducing jasmonic acid (JA) signaling while suppressing salicylic acid (SA) signaling pathways during disease development. In the present study, we show that Rso type III effector RipAF1 exerts a negative effect on bacterial virulence by subverting disease signaling in association with bacterial wilt. The ADP-ribosylation activity of RipAF1 was verified both in vivo and in vitro. Host fibrillin FBN1 was identified as a RipAF1-interacting protein that acted as a susceptible factor for bacterial wilt. In particular, RipAF1 directly ADP-ribosylates FBN1 at the E175/K207 residues, thus interfering with the mediation of disease signaling by FBN1. Together, these results suggest that RipAF1 exerts a role in defense induction by ADP-ribosylation of the susceptible factor FBN1 in the host plant.

plant biology↗

Spatial patterning and immunosuppression of glioblastoma immune contexture in hypoxic niches

Glioblastoma (GBM), a highly lethal brain cancer, is notorious for its immunosuppressive microenvironment, yet current immunotherapies are ineffective. Thus, understanding the immune contexture and governing factors of immunosuppression is crucial. Here, we identified a highly dynamic temporospatial patterning of tumor-associated macrophages (TAMs) corresponding to vascular changes in GBM: as tumor vessels transition from an initial dense regular network to later scant engorged vasculature, CD68+ TAMs shift away from perivascular regions to poorly vascularized areas. Remarkably, this process is heavily influenced by the immunocompetency of host animal, as tumor vessels in immunodeficient hosts remained dense and regular while TAMs evenly distributed. Utilizing a sensitive fluorescent reporter to track tumor hypoxia, we revealed that hypoxic niche controls immunosuppression by at least two mechanisms: first, attracting and sequestering activated TAMs in hypoxic zones, and second, reprograming entrapped TAMs towards an immunotolerant state. Indeed, entrapped TAMs also experience hypoxia and upregulate phagocytic marker Cd68 and immunotolerant genes Mrc1 and Arg1, thereby facilitating debris clearing, inflammatory containment, and immunosuppression in hypoxic zones. Mechanistically, we identified Ccl8 and IL-1{beta} as two hypoxic niche factors released by TAMs in response to cues from hypoxic GBM cells, functioning to reinforce TAM retainment. Reciprocally, niche factors also shape the transcriptional responses of hypoxic tumor cells that exhibit quiescence and mesenchymal shift. Moreover, hypoxic niche factors are highly enriched in human GBMs, particularly mesenchymal subtype, and predict poor survival. Importantly, perturbing hypoxic niches resulted in reduced TAM sequestration and better tumor control. Together, understanding the mutual influence of immune contexture and metabolic landscape has important ramifications for improving efficacy of immunotherapies against GBM.

cancer biology↗

Functional stemness-related genes revealed by single-cell profiling of naïve and stimulated human CD34+ cells from CB and mPB

Hematopoietic stem cells (HSCs) from different sources show varied repopulating capacity, and HSCs lose their stemness after long-time ex vivo culture. However, the underlying mechanisms of the stemness differences because of the cell sources and the culture stimulation are not fully understood. Here, we applied single-cell RNA-seq (scRNA-seq) to analyze the naive and stimulated human CD34+ cells from cord blood (CB) and mobilized peripheral blood (mPB). We collected over 16,000 single-cell data to construct a comprehensive trajectory inference map and characterized the HSCs population on the hierarchy top, which is under quiescent state. Then we compared HSCs in CB to those in mPB and HSCs of naive samples to those of cultured samples, and identified stemness-related genes (SRGs) associated with culture time (CT-SRGs) and cell source (CS-SRGs), respectively. Interestingly, CT-SRGs and CS-SRGs share genes enriched in the signaling pathways such as mRNA catabolic process, Translational initiation, Ribonucleoprotein complex biogenesis and Cotranslational protein targeting to membrane, suggesting dynamic protein translation and processing may be a common requirement for stemness maintenance. Meanwhile, CT-SRGs are enriched in pathways involved in glucocorticoid and corticosteroid response that affect HSCs homing and engraftment. In contrast, CS-SRGs specifically contain genes related purine and ATP metabolic process which is important to initiate hematopoiesis. Finally, we presented an application through a small-scale drug screening using Connectivity Map (CMap) against CT-SRGs and found a small molecule cucurbitacin I, targeting STAT3/JAK2, can efficiently expand HSCs ex vivo while maintaining its stemness. These results indicate SRGs revealed by scRNA-seq can provide helpful insights to understand the stemness differences under diverse circumstances, and CT-SRGs can be a valuable database to identify candidates enhancing functional HSCs expansion during ex vivo culture.

cell biology↗

A Neuropsin-based Optogenetic Tool for Precise Control of Gq signaling

Gq-coupled receptors regulate numerous physiological processes by activating enzymes and inducing intracellular Ca2+ signals. There is a strong need for an optogenetic tool that enables powerful experimental control over Gq signaling. Here, we present chicken opsin 5 (cOpn5) as the long sought-after, single-component optogenetic tool that mediates ultra-sensitive optical control of intracellular Gq signaling with high temporal and spatial resolution. Expressing cOpn5 in mammalian cells enables blue light-triggered, Gq-dependent Ca2+ release from intracellular stores and protein kinase C activation. Strong Ca2+ transients were evoked by brief light pulses of merely 10 ms duration and at 3 orders lower light intensity of that for common optogenetic tools. Photostimulation of cOpn5-expressing cells at the subcellular and single-cell levels generated intracellular and intercellular Ca2+ wave propagation, respectively, thus demonstrating the high spatial precision of cOpn5 optogenetics. The cOpn5-mediated optogenetics could also be applied to activate neurons and control animal behavior in a circuit-dependent manner. We further revealed that optogenetic activation of cOpn5-expressing astrocytes induced massive ATP release and modulation neuronal activation in the brain of awake, behaving mice. cOpn5 optogenetics may find broad applications in studying the mechanisms and functional relevance of Gq signaling in both non-excitable cells and excitable cells in all major organ systems.

neuroscience↗

Comprehensive RNA-Seq Reveals Molecular Changes in Kidney Malignancy Among People Living with HIV

BackgroundMalignancy of the kidney is a rapidly progressive kidney disease and a major source of morbidity and mortality among people living with HIV (PLWH). Patients with HIV-associated kidey cancer experience higher cancer-specific mortality than the general population, and its mechanism remains poorly understood. MethodsTo heighten the awareness of kidney malignancy in patients with HIV infection to facilitate the early diagnosis of kidney cancer, we identified 2460 protein-coding transcripts in HIV-associated kidney cancer using comprehensive RNA sequencing (RNA-seq). ResultsKISS1R, CAIX, and NPTX2 mRNA expression levels were specifically increased in HIV-associated kidney cancer, and UMOD and TMEM213 mRNA were decreased in most cases based on real-time PCR analyses. These findings were similar to those noted for the general population with renal cell carcinoma. Immunohistochemical staining analysis also showed that a total of 16 of 18 kidney malignant cases among PLWH exhibited positive staining for KISS1R and CAIX. ConclusionPathway analysis of the differentially expressed mRNAs in HIV-associated kidney cancer revealed that several key pathways were involved, including voltage-gated chloride channel activity, distal tubule development, collecting duct development, fructose metabolic processes, and negative regulation of lipase activity. The identified molecular changes in kidney malignancy may offer a helpful explanation for cancer progression and open up new therapeutic avenues that may decrease mortality after a cancer diagnosis among PLWH.

cancer biology↗

tiRNA-Val promotes angiogenesis via Sirt1-Hif-1α axis in mice with diabetic retinopathy

Diabetic retinopathy (DR) is a specific microvascular complication arising from diabetes, and its pathogenesis is notcompletely understood. tRNA-derived stress-induced RNAs (tiRNAs), a new type of small noncoding RNA generated by specific cleavage of tRNAs, has become a promising target forseveral diseases. However, the regulatory function of tiRNAs in DR and its detailed mechanism remain unknown. Here, we analyzed the tiRNA profiles of normal and DR retinal tissues. The expression level of tiRNA-Val was significantly upregulated in DR retinal tissues. Consistently, tiRNA-Val was upregulated in human retinal microvascular endothelial cells (HRMECs) under high glucose conditions. The overexpression of tiRNA-Val enhanced cell proliferation and inhibited cell apoptosis in HRMECs, but the knockdown of tiRNA-Val decreased cell proliferation and promoted cell apoptosis. Mechanistically, tiRNA-Val, derived from mature tRNA-Val with Ang cleavage, decreased Sirt1 expression level by interacting with sirt1 3UTR, leading to the accumulation of Hif-1, a key target for DR. In addition, subretinal injection of adeno-associated virus to knock down tiRNA-Val in DR mice ameliorated the symptoms of DR. Therefore, these data suggest that tiRNA-Val is a potential target in treating diabetic retinopathy.

molecular biology↗

Genetically Determined Strength of Natural Killer Cells is Enhanced by Adaptive HLA class I Admixture in East Asians

Human natural killer (NK) cells are essential for controlling infection, cancer and fetal development. NK cell functions are modulated by interactions between polymorphic inhibitory killer cell immunoglobulin-like receptors (KIR) and polymorphic HLA-A, -B and -C ligands expressed on tissue cells. All HLA-C alleles encode a KIR ligand and contribute to reproduction and immunity. In contrast, only some HLA-A and -B alleles encode KIR ligands and they focus on immunity. By high-resolution analysis of KIR and HLA-A, -B and -C genes, we show that the Chinese Southern Han are significantly enriched for interactions between inhibitory KIR and HLA-A and -B. This enrichment has had substantial input through population admixture with neighboring populations, who contributed HLA class I haplotypes expressing the KIR ligands B*46:01 and B*58:01, which subsequently rose to high frequency by natural selection. Consequently, over 80% of Southern Han HLA haplotypes encode more than one KIR ligand. Complementing the high number of KIR ligands, the Chinese Southern Han KIR locus combines a high frequency of genes expressing potent inhibitory KIR, with a low frequency of those expressing activating KIR. The Southern Han centromeric KIR region encodes strong, conserved, inhibitory HLA-C specific receptors, and the telomeric region provides a high number and diversity of inhibitory HLA-A and -B specific receptors. In all these characteristics, the Southern Han represent other East Asians, whose NK cell repertoires are thus enhanced in quantity, diversity and effector strength, likely through natural selection for resistance to endemic viral infections.

immunology↗

Evolutionary history of inversions in the direction of architecture-driven mutational pressures in crustacean mitochondrial genomes

Inversions of the origin of replication (ORI) of mitochondrial genomes produce asymmetrical mutational pressures that can cause artefactual clustering in phylogenetic analyses. It is therefore an absolute prerequisite for all molecular evolution studies that use mitochondrial data to account for ORI events in the evolutionary history of their dataset. The number of ORI events in crustaceans remains unknown; several studies reported ORI events in some crustacean lineages on the basis of fully inversed (e.g. negative vs. positive) GC skew patterns, but studies of isolated lineages could have easily overlooked ORI events that produced merely a reduction in the skew magnitude. In this study, we used a comprehensive taxonomic approach to systematically study the evolutionary history of ORI events in crustaceans using all available mitogenomes and combining signals from lineage-specific skew magnitude and direction (+ or -), cumulative skew diagrams, and gene rearrangements. We inferred 24 putative ORI events (14 of which have not been proposed before): 17 with relative confidence, and 7 speculative. Most of these were located at lower taxonomic levels, but there are indications of ORIs that occurred at or above the order-level: Copepoda, Isopoda, and putatively in Branchiopoda and Poecilostomatida+Cyclopoida. Several putative ORI events did not result in fully inversed skews. In many lineages skew plots were not informative for the prediction of replication origin and direction of mutational pressures, but inversions of the mitogenome fragment comprising the ancestral CR (rrnS-CR-trnI) were rather good predictors of skew inversions. We also found that skew plots can be a useful tool to indirectly infer the relative strengths of mutational/purifying pressures in some crustacean lineages: when purifying pressures outweigh mutational, GC skew plots are strongly affected by the strand distribution of genes, and when mutational > purifying, GC skew plots can be even completely (apparently) unaffected by the strand distribution of genes. This observation has very important repercussions for phylogenetic and evolutionary studies, as it implies that not only the relatively rare ORI events, but also much more common gene strand switches and same-strand rearrangements can produce mutational bursts, which in turn affect phylogenetic and evolutionary analyses. We argue that such compositional biases may produce misleading signals not only in phylogenetic but also in other types of evolutionary analyses (dN/dS ratios, codon usage bias, base composition, branch length comparison, etc.), and discuss several such examples. Therefore, all studies aiming to study the evolution of mtDNA sequences should pay close attention to architectural rearrangements.

evolutionary biology↗

High glucose attenuates Ca2+ influx in cytotoxic T lymphocytes upon target recognition

The killing efficiency of cytotoxic T lymphocytes (CTLs) is tightly regulated by intracellular Ca2+ concentration. Glucose is the key energy source for CTLs, lack of which significantly impairs CTL activation, proliferation and effector functions. The impact of high glucose on Ca2+ influx in CTLs remains largely elusive. In this work, we stimulated primary human CD8+ T cells in medium containing either 25 mM (high glucose, HG) or 5.6 mM glucose (normal glucose, NG). We found that store-operated calcium entry (SOCE) induced by thapsigargin (Tg) is elevated in HG-cultured CTLs compared to their counterparts in NG. Unexpectedly, the Ca2+ influx elicited by recognition of target cells is reduced in HG-cultured CTLs. Under HG condition, STIM1 and STIM2, the calcium sensors in the endoplasmic reticulum (ER), were down-regulated; ORAI1, the main structural component of calcium-release activated channels, remained unchanged, whereas ORAI2 and ORAI3 were up-regulated. The fraction of necrosis of HG-cultured CTLs was enhanced after killing without affecting glucose uptake. Thus, our findings reveal that HG has a distinctive impact on Tg-evoked SOCE and target recognition-induced Ca2+ influx in CTLs and causes more CTL death after killing, suggesting a novel regulatory role of high glucose on modulating CTL functions.

immunology↗

Three criteria of intrinsically theoretical categories in biological system and classification of some medical plants

In classical biology, different taxonomic categories are all decided based on empirical rules established on learning knowledge. In taxonomy, different classification systems are of diversified rules. One biology is often in different categories, although the concepts related to taxonomic categories are the same to each other. Whether there exist some absolute standards to classify biology, and to give unalterable results. This is of greatly scientific meaning. Common and variation, that is heredity and variation are the most elemental information in biology, and exist at multiply biology material levels. In this paper a generalized biological heredity and variation information theory was proposed based on previous works. Three typical heredity and variation models were analyzed by using this theory. They are unique asymmetric variation model, symmetric two variation model and extreme radial variation model. In the maximum information states, two biological constants Pg1 = 0.69 and Pg2=0.61 and a boundary similarity function were obtained. These Pg and Pg function can be defined as the three theoretically taxonomic category criteria of biological system. For 29 samples belonging to four kind plants, their chemical fingerprint -- infrared (IR) fingerprint spectra (FPS) were analyzed depending on the theoretical criteria. The correct classification ratio was 96.6%. The results showed these samples could be ideally classified. A suggestion was proposed that biology should be absolutely classified relying on the three intrinsic theoretical criteria.

plant biology↗

Plexin-B2 is a key regulator of cell mechanics during multicellular organization

During multicellular organization, individual cells need to constantly respond to environmental cues and adjust contractile and adhesive forces in order to maintain tissue integrity. The signaling pathways linking biochemical cues and tissue mechanics are unclear. Here, we show that Plexin-B2 regulates mechanochemical integration during multicellular organization. In human embryonic stem cells (hESCs), Plexin-B2 controls cell shape and tissue geometry in both 2D epithelial colony and 3D spheroid aggregates by regulating actomyosin contractility and junctional/cell-matrix adhesive properties. Atomic force microscopy (AFM) directly demonstrates that Plexin-B2 modulates cell stiffness in hESC colonies, which in turn impacts cell proliferation and cell fate specification through {beta}-catenin signaling and YAP mechanosensing. YAP also functions as a mechanoregulator downstream of Plexin-B2, thus forming a mechanochemical integrative loop. In human neuroprogenitor cells (hNPCs), Plexin-B2 similarly controls cell stiffness and tensile forces, as revealed by AFM and FRET tension sensor studies. Strikingly, Plexin-B2-deficient hNPCs display accelerated neuronal differentiation. From an organogenesis perspective, Plexin-B2 maintains cytoarchitectural integrity of neuroepithelium, as modeled in cerebral organoids. On a signaling level, Plexin-B2 engages extracellular as well as intracellular Ras-GAP and RBD domains for mechanoregulation through Rap and Rac GTPases. Our data unveil a fundamental function of Plexin-B2 for mechanochemical integration during multicellular organization, and shed light on the principle of force-mediated regulation of stem cell biology and tissue morphogenesis.

developmental biology↗

Effects of active dry yeast on growth performance, rumen fermentation characteristics and slaughter performance in beef cattle

This study aimed to investigate the effects of active dry yeast (ADY) on rumen microbial composition and slaughter performance of beef cattle. Thirty-two finishing beef cattle (simmental crossbred cattle [male] x cattle-yaks [female]), with an average body weight of 110 {+/-} 12.85 kg, were randomly assigned to one of four treatments: the low plane of nutrition group (Control), low plane of nutrition group + ADY 2 g/head/d (ADY2), low plane of nutrition group + ADY 4 g/head/d (ADY4) and high plane of nutrition group (HPN). ADY supplementation increased average daily gain (P<0.001), and the carcass weight of ADY4 group had no significant difference with HPN group (P>0.05). The serum glutamic-pyruvic transaminase activity in control and ADY4 group was higher than HPN group (P=0.001). The neutral detergent fiber (P=0.022) and acid detergent fiber (P=0.043) digestibility in HPN group was greater than control, but no difference was obtained among ADY2, ADY4 and HPN group (P>0.05). The rumen ammonium nitrogen content in control was greater than ADY2 and ADY4 group (P=0.003), and no difference was obtained ADY2, ADY4 and HPN group (P>0.05). The propionic acid content in the rumen in ADY2, ADY4, and HPN group were greater than control group (P<0.001). The simpson (P=0.014) and shannon (P=0.045) indexes in control and HPN group were greater than ADY4 group. At the phylum level, the relative abundance of Firmicutes in the HPN group was higher than ADY4 group (P=0.015). At the genus level, HPN and ADY4 were clustered together, and the relative abundance of Ruminococcaceae UCG-002 in ADY4 group was higher than control and HPN group (P=0.004). In conclusion, supplementation ADY 4 g/head/d shift the rumen microbial composition of beef cattle fed low plane of nutrition to a more similar level with cattle fed with HPN diet, produced comparable carcass weight with HPN diet.

zoology↗

High-Resolution Tomographic Analysis of in vitro 3D Glioblastoma Tumor Model under Long-Term Drug Treatment

Glioblastoma multiforme (GBM) is an extremely lethal type of brain tumor as it frequently develops therapeutic resistance over months of chemotherapy cycles. Hence, there is a critical need to provide relevant biological systems to guide the development of new potent personalized drugs but also efficient methodologies that enable personalized prediction of various therapeutic regimens for enhanced patient prognosis. Towards this goal, we report on the development of i) an appropriate in vitro model that mimics the 3D tumor microenvironment and ii) a companion imaging modality that enables to assess this in vitro model in its entirety. More precisely, we developed an integrated platform of bio-printing in vitro 3D GBM models and mesoscopic imaging to monitor tumor growth and invasion along with long-term drug treatment. The newly-developed in vitro 3D model contains tumor spheroids made of patient-derived glioma stem cells with a fluorescent reporter and vascular channels for drug perfusion. The imaging of these thick tissue constructs was performed using our second-Generation Mesoscopic Fluorescence Molecular Tomography (2GMFMT) imaging system which delivered 3D reconstruction of the fluidic channels and the GBM spheroids over the course of pre- and post-drug treatment (up to 70 days). The 2D measurements collected via 2GMFMT was comparable to existing imaging modalities, but 2GMFMT enabled non-sacrificial volumetric monitoring that provided a unique insgiht into the GBM spheroid growth and drug response. Overall, our integrated platform provides customizable in vitro model systems combined with an efficient long-term non-sacrificial imaging for the volumetric change of tumor mass, thus has a great potential in profoundly affecting the drug pipeline for a vast array of pathologies as well as for guiding personalized therapeutic regimen.

bioengineering↗

Distinct gut metagenomics and metaproteomics signatures in prediabetics and treatment-naïve type 2 diabetics

BackgroundThe gut microbiota plays important roles in modulating host metabolism. Previous studies have demonstrated differences in the gut microbiome of T2D and prediabetic individuals compared to healthy individuals, with distinct disease-related microbial profiles being reported in groups of different age and ethnicity. However, confounding factors such as anti-diabetic medication hamper identification of the gut microbial changes in disease development.\n\nMethodWe used a combination of in-depth metagenomics and metaproteomics analyses of faecal samples from treatment-naive type 2 diabetic (TN-T2D, n=77), pre-diabetic (Pre-DM, n=80), and normal glucose tolerant (NGT, n=97) individuals to investigate compositional and functional changes of the gut microbiota and the faecal content of microbial and host proteins in Pre-DM and treatment-naive T2D individuals to elucidate possible host-microbial interplays characterising different disease stages.\n\nFindingsWe observed distinct differences characterizing the gut microbiota of these three groups and validated several key features in an independent TN-T2D cohort. We also demonstrated that the content of several human antimicrobial peptides and pancreatic enzymes differed in faecal samples between three groups, such as reduced faecal level of antimicrobial peptides and pancreatic enzymes in TN-T2D.\n\nInterpretationOur findings suggest a complex, disease stage-dependent interplay between the gut microbiota and the host and emphasize the value of metaproteomics to gain further insight into interplays between the gut microbiota and the host.\n\nFundingNational Key Research and Development Program of China, No. 2017YFC0909703, Shenzhen Municipal Government of China, No. JCYJ20170817145809215, and National Natural Science Foundation of China, No. 31601073.

microbiology↗