A tracer model nowcast/forecast study of the Tampa Bay, Piney Point effluent plume: Rapid response to an environmental hazard.

An emergency discharge of nutrient-rich effluent from the defunct Piney Point fertilizer stack into Tampa Bay at Port Manatee occurred from 30 March-8 April 2021. This resulted in a pollutant plume that evolved over time and space across the entire bay, including its environmentally sensitive marine preserves, and out onto the adjacent continental shelf. As a rapid response to environmental concerns, the plume evolution was simulated using the high resolution, unstructured grid, Tampa Bay Coastal Ocean Model (TBCOM) nowcast/forecast system, with an embedded tracer module that included realistic point discharge rates. Normalized tracer distributions were automatically updated each day, providing 1-day hindcasts and 3.5-day forecasts. Due to mixing and advection, tracer concentration was quickly reduced by two or more orders of magnitude as the plume spread out. Highest tracer concentrations hugged the southeastern Tampa Bay shoreline during the first week. Lower tracer concentrations were gradually advected to the western side of Tampa Bay, and the tracer was slowly flushed out of the bay to be transported primarily northward along the coast. The modeled plume evolution served as principal guidance for coordinating environmental monitoring by state, local and academic personnel. The model results also provide a basis for future multidisciplinary studies.

Expeditious assembly of biuret-guanidine derivatives via the catalyst-free transformation.

We disclose a mild and practical catalyst-free transformation for the expeditious construction of biuret-guanidine derivatives using aromatic isocyanates. This synthetic transformation is featured with mild reaction conditions and high efficiency.

Zeylenone synergizes with cisplatin in osteosarcoma by enhancing DNA damage, apoptosis, and necrosis via the Hsp90/AKT/GSK3ß and Fanconi anaemia pathway.

A safer and more effective combination strategy designed to enhance the efficacy and minimize the toxicity of cisplatin in osteosarcoma (OS) is urgently needed. Zeylenone (zey), a cyclohexene oxide compound, exerted an obvious inhibitory effect on several cancer cell lines and exhibited little cytotoxicity towards normal cells, enabling zey to play a unique role in combination therapy. Thus, the study aimed to determine whether the combination of zey and cisplatin produces synergistic antitumour effects on OS and to further explore molecular mechanisms. Initially, we found that zey potentiated the anti-osteosarcoma efficacy of cisplatin and exhibited synergistic interactions with cisplatin in vitro, which also were confirmed in vivo by using xenograft model. Mechanistically, zey and cisplatin synergistically induced DNA damage, cell cycle arrest, necrosis, and apoptosis in OS cells. Importantly, zey had a high binding affinity for Hsp90 and reduced the expression of Hsp90, which further induced the suppression of AKT/GSK3ß signalling axis and the degradation of Fanconi anaemia (FA) pathway proteins. Thus, the Hsp90/AKT/GSK3ß and FA pathway are the key to the synergism between zey and cisplatin. Overall, zey shows promise for development as a cisplatin chemosensitizer with clinical utility in restoring cisplatin sensitivity of cancer cells.

Fabrication of chitin nanofiber-PDMS composite aerogels from Pickering emulsion templates with potential application in hydrophobic organic contaminant removal.

Natural polymers have aroused increasing attention in water treatment but their application in removing hydrophobic organic contaminants (HOCs) was limited due to their hydrophilicity. Herein, hydrophobic aerogels were successfully fabricated from Pickering emulsions stabilized by chitin nanofibers (ChNF) with polydimethylsiloxane (PDMS) as dispersed phase and glutaraldehyde as a crosslinking agent, and their performance in HOCs removal were evaluated. The Pickering emulsions with PDMS ratios of 2.5-20% v/v showed high stability, demonstrating great potential as aerogel templates. The solidified PDMS droplets were evenly distributed within the matrix, contributing to homogeneous and permanent hydrophobicity. The composite aerogels with water contact angles of over 130° could selectively remove non-aqueous phase HOCs from water. The CCl4 adsorption capacity was 521-2820 wt%, depending on PDMS contents. Meanwhile, the mechanical resilience of the composite aerogels was significantly improved, facilitating the adsorbent regeneration by simple mechanical squeezing. The adsorption capacity remained above 85% for 24 cycles. Moreover, the aerogels could also remove dissolved HOCs from water with a maximum adsorption capacity of 1.34 mg/g for 10 mg/L TCE. This work reveals the potential of Pickering emulsions in the fabrication of composite hydrophobic materials from natural biopolymers with promising application in HOCs related water treatment.

Bacteremia and other body site infection caused by hypervirulent and classic Klebsiella pneumoniae.

OBJECTIVES: To investigate bacteremia and other body site infection caused by hypervirulent Klebsiella pneumoniae (hvKP), a recently recognized pathogen of invasive infection, and classic Klebsiella pneumoniae (cKP), a very common organism associated with many kinds of nosocomial infection. METHODS: Clinical information obtained from patients with both bacteremia and other body site infections caused by hvKP and/or cKP was retrospectively reviewed. Homo-hvKP (or homo-cKP) was defined as homologous hvKP (or cKP) strains from different body sites in each individual patient according to string test, virulence gene amplification and PFGE pattern. MLST was carried on to understand the correlation of sequence type with capsular polysaccharide type for Klebsiella pneumoniae from blood. RESULTS: Sixty-four hvKP and 101 cKP strains were isolated from blood and other body sites of 76 patients who had bacteremia accompanied by other site infection. Among these patients, 27 were infected with homo-hvKP, 32 were with homo-cKP, 12 were with heterogeneous cKP, and five were with both hvKP and cKP. Patients with bacteremia and liver abscesses caused by homo-hvKP accounted for 51.9%, and 92.6% of homo-hvKP infected patients did not receive any invasive procedures before bacteremia. However, patients with bacteremia and biliary tract infection caused by homo-cKP accounted for 34.4%, and 78.1% of homo-cKP infected patients had history of invasive procedures before bacteremia. More homo-hvKP strains (59.3%) than homo-cKP strains (34.4%) were isolated from blood earlier than other sites. HvKP strains were statistically more susceptible to the tested antimicrobials than cKP strains. An outbreak of carbapenem-resistant cKP infection and possible gene transfer of KPC-2 from cKP to hvKP were brought to notice. CONCLUSIONS: Both hvKP and cKP could cause bacteremia and other body site infection. But patients with hvKP bacteremia usually suffered from liver abscess without previous invasive procedures, most patients with cKP bacteremia had history of invasive medical procedures.

Clinical and Molecular Analysis of Klebsiella pneumoniae Causing Liver Abscess in China.

OBJECTIVE: Hypervirulent Klebsiella pneumoniae (hvKP) has been characterized as the major pathogen associated with the development of liver abscesses. Although the prevalence of K. pneumoniae in liver abscesses in Chinese patients is on the rise, methods for the early laboratory identification and recognition of hvKP are lacking, and hvKP detection and surveillance are thus limited. METHODS: A retrospective study was conducted in 240 patients with cultures that were positive for K. pneumoniae, who were hospitalized in the Hospital of Beijing area from May 2013 to August 2014. The clinical and molecular characteristics of K. pneumoniae strains that cause liver abscesses were studied. Thirty-eight (16.7%) of 240 patients positive for K. pneumoniae cultures had liver abscesses. RESULTS: Among these K. pneumoniae isolates, 92.1% (35/38) and 84.2% (32/38) were rmpA and aerobactin (abc) positive, respectively, as indicated by multiplex PCR, while 81.6% (31/38) were string test positive. Intriguingly, K. pneumoniae isolates that were positive for rmpA, abc, or string test accounted for almost all isolates (97.3%; n = 37/38) and thus were defined as hvKP in this study. Based on the new criteria for hvKP, none of these hvKP strains were positive for extended spectrum ß-lactamases. CONCLUSIONS: Compared to the string test alone, integrating rmpA and abc detection with the string test is robuster and more extensive in the identification of liver abscess-causing hvKP strains. Multiplex PCR assays may therefore accelerate the early laboratory detection of hvKP.

Global epigenomic analysis indicates that epialleles contribute to Allele-specific expression via Allele-specific histone modifications in hybrid rice.

BACKGROUND: For heterozygous genes, alleles on the chromatin from two different parents exhibit histone modification variations known as allele-specific histone modifications (ASHMs). The regulation of allele-specific gene expression (ASE) by ASHMs has been reported in animals. However, to date, the regulation of ASE by ASHM genes remains poorly understood in higher plants. RESULTS: We used chromatin immunoprecipitation followed by next-generation sequencing (ChIP-seq) to investigate the global ASHM profiles of trimethylation on histone H3 lysine 27 (H3K27me3) and histone H3 lysine 36 (H3K36me3) in two rice F1 hybrids. A total of 522 to 550 allele-specific H3K27me3 genes and 428 to 494 allele-specific H3K36me3 genes were detected in GL × 93-11 and GL × TQ, accounting for 11.09% and 26.13% of the total analyzed genes, respectively. The epialleles between parents were highly related to ASHMs. Further analysis indicated that 52.48% to 70.40% of the epialleles were faithfully inherited by the F1 hybrid and contributed to 33.18% to 46.55% of the ASHM genes. Importantly, 66.67% to 82.69% of monoallelic expression genes contained the H3K36me3 modification. Further studies demonstrated a significant positive correlation of ASE with allele-specific H3K36me3 but not with H3K27me3, indicating that ASHM-H3K36me3 primarily regulates ASE in this study. CONCLUSIONS: Our results demonstrate that epialleles from parents can be inherited by the F1 to produce ASHMs in the F1 hybrid. Our findings indicate that ASHM-H3K36me3, rather than H3K27me3, mainly regulates ASE in hybrid rice.

The OsSec18 complex interacts with P0(P1-P2)2 to regulate vacuolar morphology in rice endosperm cell.

BACKGROUND: Sec18p/N-ethylmaleimide-sensitive factor (NSF) is a conserved eukaryotic ATPase, which primarily functions in vesicle membrane fusion from yeast to human. However, the function of the OsSec18 gene, a homologue of NSF in rice, remains unknown. RESULTS: In the present study, we investigated the function of OsSec18 in rice and found that OsSec18 complements the temperature-sensitive phenotype and interferes with vacuolar morphogenesis in yeast. Overexpression of OsSec18 in rice decreased the plant height and 1000-grain weight and altered the morphology of the protein bodies. Further examination revealed that OsSec18 presented as a 290-kDa complex in rice endosperm cells. Moreover, Os60sP0 was identified a component of this complex, demonstrating that the OsSec18 complex contains another complex of P0(P1-P2)2 in rice endosperm cells. Furthermore, we determined that the N-terminus of OsSec18 can interact with the N- and C-termini of Os60sP0, whereas the C-terminus of OsSec18 can only interact with the C-terminus of Os60sP0. CONCLUSION: Our results revealed that the OsSec18 regulates vacuolar morphology in both yeast and rice endosperm cell and the OsSec18 interacts with P0(P1-P2)2 complex in rice endosperm cell.

A SNP in OsMCA1 responding for a plant architecture defect by deactivation of bioactive GA in rice.

Plant architecture directly affects biomass in higher plants, especially grain yields in agricultural crops. In this study, we characterized a recessive mutant, plant architecture determinant (pad), derived from the Oryza sativa ssp. indica cultivar MH86. The mutant exhibited severe dwarf phenotypes, including shorter and stunted leaves, fewer secondary branches during both the vegetative and reproductive growth stages. Cytological studies revealed that pad mutant growth defects are primarily due to the inhibition of cell expansion. The PAD gene was isolated using a map-based cloning strategy. It encodes a plasma membrane protein OsMCA1 and a SNP responsible for a single amino acid change was found in the mutant. PAD was universally expressed in rice tissues from the vegetative to reproductive growth stages, especially in seedlings, nodes and rachillae. Quantitative real-time PCR analysis revealed that the most of the genes responding to gibberellin (GA) metabolism were up-regulated in pad mutant internodes. The endogenous GA content measurement revealed that the levels of GA1 were significantly decreased in the third internode of pad mutants. Moreover, a GA response assay suggested that OsMCA1/PAD might be involved in the regulation of GA metabolism and signal transduction. Our results revealed the pad is a loss-of-function mutant of the OsMCA1/PAD, leading to upregulation of genes related to GA deactivation, which decreased bioactive GA levels.

[The clinical and bacterial features of Klebsiella pnuemoniae liver abscess].

OBJECTIVE: To summarize the clinical and bacterial features of Klebsiella pnuemoniae liver abscess (KPLA) in order to provide the basis for the diagnosis and treatment of KPLA. METHODS: Retrospective study was conducted. One hundred and fifty-two medical records, from 3 teaching hospitals in Beijing, between January 2010 and December 2014, were collected. Among which 137 complete medical records were analyzed. String test was carried out to detect the hypermucoviscosity phenotype. PCR was performed to check the capsular serotype and the virulent genes. Disk diffusion method was operated to obtain the antimicrobial resistance rates. The results were analyzed by chi-square test. RESULTS: KPLA occurred mostly in middle-aged, male and diabetes mellitus patients. 92.7% (127/137) patients had fever. 80.3% (110/137) of the KLPA were single abscess, among which 80.9% (89/110) were in the right lobe and 33.6% (46/137) had air cavities.74.5% (102/137) of the white blood cell count, 83.2% (114/137) of the neutrophils' percentage, 78.1% (107/137) of alanine aminotransferase and 51.8% (71/137) of the total billrubin were elevated. 87.5% (133/152) of the Klebsiella pnuemoniae (Kpn) appeared to be hypermucoviscous, K1 was the most popular serotype, the second was K2, and the positive rates of virulent genes rmpA and aerobactin were 82.9% (126/152) and 88.2% (134/152), respectively. Among the isolates from the KPLA without other hepatobiliary diseases, the portion of K1 serotype, the positive rates of rmpA and aerobactin were 65.7%, 94.9% and 96.0%, respectively, higher than those of the 28.9%, 50.0% and 68.4% from the KPLA with other hepatobiliary diseases, while the undefined serotype potion was lower (5.1% vs 26.3%), the differences were statistically significant (χ(2)=14.98, 38.40, 17.61, 10.65, all P<0.01). Most of Kpn were susceptible to antimicrobials. CONCLUSIONS: KPLA has certain clinical features, and are mostly caused by hypervirulent isolates that are hypermucoviscous with rmpA and aerobactin genes. Most of the isolates are susceptible to antimicrobials.

Global RNA sequencing reveals that genotype-dependent allele-specific expression contributes to differential expression in rice F1 hybrids.

BACKGROUND: Extensive studies on heterosis in plants using transcriptome analysis have identified differentially expressed genes (DEGs) in F1 hybrids. However, it is not clear why yield in heterozygotes is superior to that of the homozygous parents or how DEGs are produced. Global allele-specific expression analysis in hybrid rice has the potential to answer these questions. RESULTS: We report a genome-wide allele-specific expression analysis using RNA-sequencing technology of 3,637-3,824 genes from three rice F1 hybrids. Of the expressed genes, 3.7% exhibited an unexpected type of monoallelic expression and 23.8% showed preferential allelic expression that was genotype-dependent in reciprocal crosses. Those genes exhibiting allele-specific expression comprised 42.4% of the genes differentially expressed between F1 hybrids and their parents. Allele-specific expression accounted for 79.8% of the genes displaying more than a 10-fold expression level difference between an F1 and its parents, and almost all (97.3%) of the genes expressed in F1, but non-expressed in one parent. Significant allelic complementary effects were detected in the F1 hybrids of rice. CONCLUSIONS: Analysis of the allelic expression profiles of genes at the critical stage for highest biomass production from the leaves of three different rice F1 hybrids identified genotype-dependent allele-specific expression genes. A cis-regulatory mechanism was identified that contributes to allele-specific expression, leading to differential gene expression and allelic complementary effects in F1 hybrids.

Therapeutic effect of recombinant plasmid-encoded human interleukin-12 in tumor-bearing mice.

The aim of this study was to investigate the effects of gene therapy using a recombinant plasmid encoding human interleukin-12 (rIL-12, pcDNA6-p70) on transplanted tumors in mice. Tumor-bearing mice were transplanted with sarcoma­180 (S-180) cells and randomly divided into three groups of 10 mice with each group receiving a separate treatment. Following this, pcDNA6-p70 (dissolved in purified water; 100 µg/mouse), cyclophosphamide (dissolved in 0.9% saline; 40 mg/kg) or 0.9% saline (100 µl/mouse) was directly injected into the tumors on the 4th, 7th, 10th, 14th and 17th days following transplantation of the S-180 cells. Mice survival time was monitored and surviving mice were sacrificed on the 21st day. In addition to survival time, tumor volume, NK cell activity, spleen lymphocyte proliferation and IFN-γ production were investigated. The mice were also monitored for any adverse effects regarding the administration of pcDNA6-p70. Our results demonstrated that pcDNA6-p70 prolongs the survival time of tumor-bearing mice, decreases tumor size (P<0.01) and increases the proliferative response of spleen cells, the activity of NK cells and the serum level of IFN-γ. There were no significant adverse effects caused by the administration of pcDNA6-p70. The results of the present study support the hypothesis that gene therapy using the rIL-12 plasmid exerts a therapeutic effect in tumor models by triggering antitumor cellular immunity.

Large-scale production of functional human serum albumin from transgenic rice seeds.

Human serum albumin (HSA) is widely used in clinical and cell culture applications. Conventional production of HSA from human blood is limited by the availability of blood donation and the high risk of viral transmission from donors. Here, we report the production of Oryza sativa recombinant HSA (OsrHSA) from transgenic rice seeds. The level of OsrHSA reached 10.58% of the total soluble protein of the rice grain. Large-scale production of OsrHSA generated protein with a purity >99% and a productivity rate of 2.75 g/kg brown rice. Physical and biochemical characterization of OsrHSA revealed it to be equivalent to plasma-derived HSA (pHSA). The efficiency of OsrHSA in promoting cell growth and treating liver cirrhosis in rats was similar to that of pHSA. Furthermore, OsrHSA displays similar in vitro and in vivo immunogenicity as pHSA. Our results suggest that a rice seed bioreactor produces cost-effective recombinant HSA that is safe and can help to satisfy an increasing worldwide demand for human serum albumin.

Proteomic analysis of rice endosperm cells in response to expression of hGM-CSF.

The accumulation of significant levels of transgenic products in plant cells is required not only for crop improvement, but also for molecular pharming. However, knowledge about the fate of transgenic products and endogenous proteins in grain cells is lacking. Here, we utilized a quantitative mass spectrometry-based proteomic approach for comparative analysis of expression profiles of transgenic rice endosperm cells in response to expression of a recombinant pharmaceutical protein, human granulocyte-macrophage colony stimulation factor (hGM-CSF). This study provided the first available evidence concerning the fate of exogenous and endogenous proteins in grain cells. Among 1883 identified proteins with a false positive rate of 5%, 103 displayed significant changes (p-value < 0.05) between the transgenic and the wild-type endosperm cells. Notably, endogenous storage proteins and most carbohydrate metabolism-related proteins were down-regulated, while 26S proteasome-related proteins and chaperones were up-regulated in the transgenic rice endosperm. Furthermore, it was observed that expression of hGM-CSF induced endoplasmic reticulum stress and activated the ubiquitin/26S-proteasome pathway, which led to ubiquitination of this foreign gene product in the transgenic rice endosperm.