'Is it painful'? A qualitative study on experiences of patients before prostate needle biopsy.

OBJECTIVE: To assess the experiences and emotional reactions of men prior to receiving a prostate needle biopsy (PNB). DESIGN: This was a qualitative study involving (1) material research and filter, (2) interviewer training, (3) cognitive semistructured interviews with open-ended questions, (4) data analysis, including translation and back translation and (5) group discussions to determine common themes in the data. All interviews were digitally audio-recorded. The thematic analysis was conducted by repeatedly reading the data manuscript and engaging in group discussion. SETTING AND PARTICIPANTS: A total of 30 participants with suspected prostate cancer (PC) who were scheduled to receive a PNB were interviewed. Eligible participants were Chinese native men aged 51-77 years, and the study was conducted in China between September and December 2020. All participants were informed about the purpose of the study and provided written informed consent. RESULTS: Four main themes were identified based on the interview content: (1) fear (of pain, adverse effects and bad results), (2) impact of lower urinary tract symptoms (on emotional impact, work and sleeping), (3) inner struggles (relating to hesitation, regret and embarrassment) and (4) lifestyle change (including diet, exercise and receipt of traditional Chinese medicine). CONCLUSIONS: This patient cohort had a low level of knowledge about PC and PNB. Providing additional education about these topics would help to reduce patient fear and anxiety and improve experiences of the procedure.

Arbuscular Mycorrhizal Fungi Compete Asymmetrically for Amino Acids with Native and Invasive Solidago.

Arbuscular mycorrhizal fungi (AMF) and soil amino acids both affect plant performance. However, little is known about how AMF compete for amino acids with native and invasive congeners. We conducted a factorial experiment (inoculation, native and invasive species, and amino acids) to examine the competition for amino acids between soil microbes and both native and invasive congeners. The competition for amino acids between AMF and invasive Solidago canadensis was weaker than that observed between AMF and native S. decurrens. This asymmetric competition increased the growth advantage of S. canadensis over S. decurrens. The efficacy (biomass production per unit of nitrogen supply) of amino acids compared to ammonium was smaller in S. canadensis than in S. decurrens when both species were grown without inoculation, but the opposite was the case when both species were grown with AMF. AMF and all microbes differentially altered four phenotypic traits (plant height, leaf chlorophyll content, leaf number, and root biomass allocation) and the pathways determining the effects of amino acids on growth advantages. These findings suggest that AMF could enhance plant invasiveness through asymmetric competition for amino acids and that amino acid-driven invasiveness might be differentially regulated by different microbial guilds.

Application of the Nursing Model Based on Acceptance and Commitment Therapy (ACT) in Improving Mental Health and Quality of Life after Colorectal Cancer Drug Chemotherapy.

According to the most current cancer impact statistics, third most commonly diagnosed cancer worldwide is colorectal cancer. Colon cancer, in addition to its physical symptoms, has been linked to mental health issues in patients, according to the study. Dealing with colorectal cancer drug chemotherapy may lead to depression and anxiety in some people. Others are affected by the physical and mental condition of undergoing many therapies at the same time. Throughout the process of diagnosis, a large number of colorectal cancer patients report clinically relevant degrees as well as a decline in overall mental wellness. In the majority of cases, colon cancer patients are cured following therapy, but those who have survived the disease confront a medical range, physical, and challenges in society, for a variety of mental and physical problems such as anxiety and depression. First, meditation therapy is to urge patients to address their issues and feelings instead of dismissing them, but in the dispassionate and unbiased manner that defines the attentive state. Both the patient and the treating professional may benefit from this treatment method, since it appears to be a very effective therapeutic strategy. After colorectal cancer treatment, in studies, it has been demonstrated that ACT improves mental health, and Internet search engines such as Web of Science and Google Scholar as well as Dialnet were utilized to conduct a systematic literature There were 19 articles that fit the criteria. This includes a discussion of the ACT's philosophical and theoretical basis, as well as the treatment itself. On the other hand, the study on ACT for enhancing mental health and quality of life is examined. Several of the available trials had serious flaws, making it impossible to establish reliable conclusions about the effectiveness of ACT for improving mental health and quality of life. The study determined that there is only a small amount of data supporting the use of ACT for improving mental health. The aim of this study is the application of the nursing model on improving the mental health of the colorectal patients. In addition, the limits of the current empirical state of ACT are acknowledged, and the importance of further research is highlighted.

Recent Insights Into the Protective Mechanisms of Paeoniflorin in Neurological, Cardiovascular, and Renal Diseases.

ABSTRACT: The monoterpene glycoside paeoniflorin (PF) is the principal active constituent of the traditional Chinese herbal medicines, Radix Paeoniae Alba and Radix Paeoniae Rubra, which have been used for millennia to treat cardiovascular diseases (eg, hypertension, bleeding, and atherosclerosis) and neurological ailments (eg, headaches, vertigo, dementia, and pain). Recent evidence has revealed that PF exerts inhibitory effects on inflammation, fibrosis, and apoptosis by targeting several intracellular signaling cascades. In this review, we address the current knowledge about the pharmacokinetic properties of PF and its molecular mechanisms of action. We also present results from recent preclinical studies supporting the utility of PF for the treatment of pain, cerebral ischemic injury, and neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases. Moreover, new evidence suggests a general protective role of PF in heart attack, diabetic kidney, and atherosclerosis. Mechanistically, PF exerts multiple anti-inflammatory actions by targeting toll-like receptor-mediated signaling in both parenchymal and immune cells (in particular, macrophages and dendritic cells). A better understanding of the molecular actions of PF may lead to the expansion of its therapeutic uses.

Submerged macrophytes successfully restored a subtropical aquacultural lake by controlling its internal phosphorus loading.

Intensive aquaculture has largely changed the global phosphorus (P) flow and become one of the main reasons for the eutrophication of global aquatic ecosystem. Artificial planting submerged macrophytes has attracted enormous interest regarding the restoration of eutrophic lakes. However, few large-scale (>80 km2) studies have focused on the restoration of aquatic vegetation in the subtropical lakes, and the mechanism underlying the restrain of sediment P release by macrophytes remains unknown. In this study, field surveys and the diffusive gradients in thin films (DGT) technique were used to elucidate the effects of macrophytes on internal P loading control in a typical eutrophic aquacultural lake. Results showed that half of the P content in overlying water and sediments, particularly dissolved P in overlying water and calcium bound P (Ca-P) in sediment, were removed after restoration. Temperature, as well as dissolved oxygen (DO) and P concentration gradients near the sediment-water interface (SWI) jointly controlled the release of labile P from surface sediments. Submerged macrophytes can effectively inhibit the release of sediment P into the overlying water, which depended on DO concentration in the bottom water. Future restoration projects should focus on the temperature response of submerged macrophytes of different growth forms (especially canopy-forming species) to avoid undesirable restoration effects. Our results complement existing knowledge about submerged macrophytes repairing subtropical P-contaminated lakes and have positive significance for lake restoration by in situ phytoremediation.

Fermentative production of Vitamin E tocotrienols in Saccharomyces cerevisiae under cold-shock-triggered temperature control.

The diverse physiological functions of tocotrienols have listed them as valuable supplementations to α-tocopherol-dominated Vitamin E products. To make tocotrienols more readily available, tocotrienols-producing S. cerevisiae has been constructed by combining the heterologous genes from photosynthetic organisms with the endogenous shikimate pathway and mevalonate pathway. After identification and elimination of metabolic bottlenecks and enhancement of precursors supply, the engineered yeast can produce tocotrienols at yield of up to 7.6 mg/g dry cell weight (DCW). In particular, proper truncation of the N-terminal transit peptide from the plant-sourced enzymes is crucial. To further solve the conflict between cell growth and tocotrienols accumulation so as to enable high-density fermentation, a cold-shock-triggered temperature control system is designed for efficient control of two-stage fermentation, leading to production of 320 mg/L tocotrienols. The success in high-density fermentation of tocotrienols by engineered yeast sheds light on the potential of fermentative production of vitamin E tocochromanols.

Culture of Small Colony Variant of Pseudomonas aeruginosa and Quantitation of its Alginate.

Pseudomonas aeruginosa, an opportunistic Gram-negative bacterial pathogen, can overproduce an exopolysaccharide alginate resulting in a unique phenotype called mucoidy. Alginate is linked to chronic lung infections resulting in poor prognosis in patients with cystic fibrosis (CF). Understanding the pathways that regulate the production of alginate can aid in the development of novel therapeutic strategies targeting the alginate formation. Another disease-related phenotype is the small colony variant (SCV). SCV is due to the slow growth of bacteria and often associated with increased resistance to antimicrobials. In this paper, we first show a method of culturing a genetically defined form of P. aeruginosa SCV due to pyrimidine biosynthesis mutations. Supplementation of nitrogenous bases, uracil or cytosine, returns the normal growth to these mutants, demonstrating the presence of a salvage pathway that scavenges free bases from the environment. Next, we discuss two methods for the measurement of bacterial alginate. The first method relies on the hydrolysis of the polysaccharide to its uronic acid monomer followed by derivatization with a chromogenic reagent, carbazole, while the second method uses an ELISA based on a commercially available, alginate-specific mAb. Both methods require a standard curve for quantitation. We also show that the immunological method is specific for alginate quantification and may be used for the measurement of alginate in the clinical specimens.

Efficacy of Aerosolized Rifaximin versus Tobramycin for Treatment of Pseudomonas aeruginosa Pneumonia in Mice.

Pseudomonas aeruginosa is a Gram-negative opportunistic bacterial pathogen that can cause chronic lung infections in patients with cystic fibrosis (CF). The current preferred treatment for CF lung infections includes inhaled tobramycin (TOB); however, studies suggest TOB cannot effectively inhibit biofilm formation. Using an NIH small compounds drug library approved for safe use in humans, we identified rifaximin (RFX), a semisynthetic, rifamycin family, nonsystemic antibiotic that inhibits alginate production and growth in P. aeruginosa Inhibition of alginate production was further analyzed using the uronic acid carbazole assay and a promoter reporter assay that measures the transcription of the alginate biosynthetic operon. Compared to TOB, RFX significantly reduced alginate production in laboratory and CF sputum isolates of P. aeruginosa In addition, RFX showed a narrow range of MICs when measured with multidrug-resistant bacterial species of clinical relevance, synergistic activities with TOB or amikacin against clinical isolates, as well as reduction toward in vitro preformed biofilms. In C57BL/6 mice, penetration of nebulized TOB into the lungs was shown at a higher level than that of RFX. Further, in vivo assessment using a DBA/2 mouse lung infection model found increased survival rates with a single-dose treatment of nebulized RFX and decreased P. aeruginosa PAO1 bioburden with a multiple-dose treatment of RFX plus TOB. In addition, mice treated with a single exposure to dimethyl sulfoxide (DMSO), a solvent that dissolves RFX, showed no apparent toxicity. In summary, RFX may be used to supplement TOB inhalation therapy to increase efficacy against P. aeruginosa biofilm infections.

Pyrimidine Biosynthesis Regulates the Small-Colony Variant and Mucoidy in Pseudomonas aeruginosa through Sigma Factor Competition.

Mucoidy due to alginate overproduction by the Gram-negative bacterium Pseudomonas aeruginosa facilitates chronic lung infections in patients with cystic fibrosis (CF). We previously reported that disruption in de novo synthesis of pyrimidines resulted in conversion to a nonmucoid small-colony variant (SCV) in the mucoid P. aeruginosa strain (PAO581), which has a truncated anti-sigma factor, MucA25, that cannot sequester sigma factor AlgU (AlgT). Here, we showed that supplementation with the nitrogenous bases uracil or cytosine in growth medium complemented the SCV to normal growth, and nonmucoidy to mucoidy, in these mucA25 mutants. This conversion was associated with an increase in intracellular levels of UMP and UTP suggesting that nucleotide restoration occurred via a salvage pathway. In addition, supplemented pyrimidines caused an increase in activity of the alginate biosynthesis promoter (P algD ), but had no effect on P algU , which controls transcription of algU Cytosolic levels of AlgU were not influenced by uracil supplementation, yet levels of RpoN, a sigma factor that regulates nitrogen metabolism, increased with disruption of pyrimidine synthesis and decreased after supplementation of uracil. This suggested that an elevated level of RpoN in SCV may block alginate biosynthesis. To support this, we observed that overexpressing rpoN resulted in a phenotypic switch to nonmucoidy in PAO581 and in mucoid clinical isolates. Furthermore, transcription of an RpoN-regulated promoter increased in the mutants and decreased after uracil supplementation. These results suggest that the balance of RpoN and AlgU levels may regulate growth from SCV to mucoidy through sigma factor competition for P algDIMPORTANCE Chronic lung infections with P. aeruginosa are the main cause of morbidity and mortality in patients with cystic fibrosis. This bacterium overproduces a capsular polysaccharide called alginate (also known as mucoidy), which aids in bacterial persistence in the lungs and in resistance to therapeutic regimens and host immune responses. The current study explores a previously unknown link between pyrimidine biosynthesis and mucoidy at the level of transcriptional regulation. Identifying/characterizing this link could provide novel targets for the control of bacterial growth and mucoidy. Inhibiting mucoidy may improve antimicrobial efficacy and facilitate host defenses to clear the noncapsulated P. aeruginosa bacteria, leading to improved prognosis for patients with cystic fibrosis.

The assessment of multipotent cell transplantation in acute-on-chronic liver failure: a systematic review and meta-analysis.

Acute-on-chronic liver failure (ACLF) is a serious life-threatening disease with high prevalence. Liver transplantation is the only efficient clinical treatment for ACLF. Because of the rapid progression and lack of liver donors, it is urgent to find an effective and safe therapeutic approach to ACLF. Recent studies showed that multipotent cell transplantation could improve the patients' liver function and enhance their preoperative condition. Cells such as mesenchymal stem cells, bone marrow mononuclear cells and autologous peripheral blood stem cells, which addressed in this study have all been used in multipotent cell transplantation for liver diseases. However, its clinical efficiency is still debatable. This systematic review and meta-analysis explored the clinical efficiency of multipotent cell transplantation as a therapeutic approach for patients with ACLF. A detailed search of the Cochrane Library, MEDLINE, and Embase databases was conducted from inception to November 2017. The outcome measures were serum albumin, prothrombin time, alanine aminotransferase, total bilirubin, platelets, hemoglobin, white blood cells, and survival time. The quality of evidence was assessed using GRADEpro and Jaded scores. A literature search resulted in 537 citations. Of these, 9 articles met the inclusion criteria. It was found that multipotent cell transplantation was able to alleviate liver damage and improve liver function. Multipotent cell transplantation can also enhance the short-term and medium-term survival rates of ACLF. All 9 research articles included in this analysis reported no statistically significant adverse events, side effects, or complications. In conclusions, this study suggested that multipotent cell transplantation could be recommended as a potential therapeutic supplementary tool in clinical practice. However, clinical trials in large-volume centers still needed.

Ischemic or toxic injury: A challenging diagnosis and treatment of drug-induced stenosis of the sigmoid colon.

A 48-year-old woman was admitted with 15-mo history of abdominal pain, diarrhea and hematochezia, and 5-mo history of defecation difficulty. She had been successively admitted to nine hospitals, with an initial diagnosis of inflammatory bowel disease with stenotic sigmoid colon. Findings from computed tomography virtual colonoscopy, radiography with meglumine diatrizoate, endoscopic balloon dilatation, metallic stent implantation and later overall colonoscopy, coupled with the newfound knowledge of compound Qingdai pill-taking, led to a subsequent diagnosis of ischemic or toxic bowel disease with sigmoid colon stenosis. The patient was successfully treated by laparoscopic sigmoid colectomy, and postoperative pathological examination revealed ischemic or toxic injury of the sigmoid colon, providing a final diagnosis of drug-induced sigmoid colon stenosis. This case highlights that adequate awareness of drug-induced colon stenosis has a decisive role in avoiding misdiagnosis and mistreatment. The diagnostic and therapeutic experiences learnt from this case suggest that endoscopic balloon expansion and colonic metallic stent implantation as bridge treatments were demonstrated as crucial for the differential diagnosis of benign colonic stenosis. Skillful surgical technique and appropriate perioperative management helped to ensure the safety of our patient in subsequent surgery after long-term use of glucocorticoids.

Recent research progress with phospholipase C from Bacillus cereus.

Phospholipase C (PLC) catalyzes the hydrolysis of phospholipids to produce phosphate monoesters and diacylglycerol. It has many applications in the enzymatic degumming of plant oils. PLC Bc , a bacterial PLC from Bacillus cereus, is an optimal choice for this activity in terms of its wide substrate spectrum, high activity, and approved safety. Unfortunately, its large-scale production and reliable high-throughput screening of PLC Bc remain challenging. Herein, we summarize the research progress regarding PLC Bc with emphasis on the screening methods, expression systems, catalytic mechanisms and inhibitor of PLC Bc . This review hopefully will inspire new achievements in related areas, to promote the sustainable development of PLC Bc and its application.

What determines positive, neutral, and negative impacts of Solidago canadensis invasion on native plant species richness?

Whether plant invasions pose a great threat to native plant diversity is still hotly debated due to conflicting findings. More importantly, we know little about the mechanisms of invasion impacts on native plant richness. We examined how Solidago canadensis invasion influenced native plants using data from 291 pairs of invaded and uninvaded plots covering an entire invaded range, and quantified the relative contributions of climate, recipient communities, and S. canadensis to invasion impacts. There were three types of invasion consequences for native plant species richness (i.e., positive, neutral, and negative impacts). Overall, the relative contributions of recipient communities, S. canadensis and climate to invasion impacts were 71.39%, 21.46% and 7.15%, respectively; furthermore, the roles of recipient communities, S. canadensis and climate were largely ascribed to plant diversity, density and cover, and precipitation. In terms of direct effects, invasion impacts were negatively linked to temperature and native plant communities, and positively to precipitation and soil microbes. Soil microbes were crucial in the network of indirect effects on invasion impacts. These findings suggest that the characteristics of recipient communities are the most important determinants of invasion impacts and that invasion impacts may be a continuum across an entire invaded range.

A novel "dual-potential" electrochemiluminescence aptasensor array using CdS quantum dots and luminol-gold nanoparticles as labels for simultaneous detection of malachite green and chloramphenicol.

A novel type of "dual-potential" electrochemiluminescence (ECL) aptasensor array was fabricated on a homemade screen-printed carbon electrode (SPCE) for simultaneous detection of malachite green (MG) and chloramphenicol (CAP) in one single assay. The SPCE substrate consisted of a common Ag/AgCl reference electrode, carbon counter electrode and two carbon working electrodes (WE1 and WE2). In the system, CdS quantum dots (QDs) were modified on WE1 as cathode ECL emitters and luminol-gold nanoparticles (L-Au NPs) were modified on WE2 as anode ECL emitters. Then the MG aptamer complementary strand (MG cDNA) and CAP aptamer complementary strand (CAP cDNA) were attached on CdS QDs and L-Au NPs, respectively. The cDNA would hybridize with corresponding aptamer that was respectively tagged with cyanine dye (Cy5) (as quenchers of CdS QDs) and chlorogenic acid (CA) (as quenchers of l-Au NPs) using poly(ethylenimine) (PEI) as a bridging agent. PEI could lead to a large number of quenchers on the aptamer, which increased the quenching efficiency. Upon MG and CAP adding, the targets could induce strand release due to the highly affinity of analytes toward aptamers. Meanwhile, it could release the Cy5 and CA, which recovered cathode ECL of CdS QDs and anode ECL of L-Au NPs simultaneously. This "dual-potential" ECL strategy could be used to detect MG and CAP with the linear ranges of 0.1-100 nM and 0.2-150 nM, with detection limits of 0.03 nM and 0.07 nM (at 3sB), respectively. More importantly, this designed method was successfully applied to determine MG and CAP in real fish samples and held great potential in the food analysis.

Highly efficient biosynthesis of astaxanthin in Saccharomyces cerevisiae by integration and tuning of algal crtZ and bkt.

Astaxanthin is a highly valued carotenoid with strong antioxidant activity and has wide applications in aquaculture, food, cosmetic, and pharmaceutical industries. The market demand for natural astaxanthin promotes research in metabolic engineering of heterologous hosts for astaxanthin production. In this study, an astaxanthin-producing Saccharomyces cerevisiae strain was created by successively introducing the Haematococcus pluvialis ß-carotenoid hydroxylase (crtZ) and ketolase (bkt) genes into a previously constructed ß-carotene hyperproducer. Further integration of strategies including codon optimization, gene copy number adjustment, and iron cofactor supplementation led to significant increase in the astaxanthin production, reaching up to 4.7 mg/g DCW in the shake-flask cultures which is the highest astaxanthin content in S. cerevisiae reported to date. Besides, the substrate specificity of H. pluvialis CrtZ and BKT and the probable formation route of astaxanthin from ß-carotene in S. cerevisiae were figured out by expressing the genes separately and in combination. The yeast strains engineered in this work provide a basis for further improving biotechnological production of astaxanthin and might offer a useful general approach to the construction of heterologous biosynthetic pathways for other natural products.

Identification of novel genes associated with alginate production in Pseudomonas aeruginosa using mini-himar1 mariner transposon-mediated mutagenesis.

Pseudomonas aeruginosa is a Gram-negative, environmental bacterium with versatile metabolic capabilities. P. aeruginosa is an opportunistic bacterial pathogen which establishes chronic pulmonary infections in patients with cystic fibrosis (CF). The overproduction of a capsular polysaccharide called alginate, also known as mucoidy, promotes the formation of mucoid biofilms which are more resistant than planktonic cells to antibiotic chemotherapy and host defenses. Additionally, the conversion from the nonmucoid to mucoid phenotype is a clinical marker for the onset of chronic infection in CF. Alginate overproduction by P. aeruginosa is an endergonic process which heavily taxes cellular energy. Therefore, alginate production is highly regulated in P. aeruginosa. To better understand alginate regulation, we describe a protocol using the mini-himar1 transposon mutagenesis for the identification of novel alginate regulators in a prototypic strain PAO1. The procedure consists of two basic steps. First, we transferred the mini-himar1 transposon (pFAC) from host E. coli SM10/λpir into recipient P. aeruginosa PAO1 via biparental conjugation to create a high-density insertion mutant library, which were selected on Pseudomonas isolation agar plates supplemented with gentamycin. Secondly, we screened and isolated the mucoid colonies to map the insertion site through inverse PCR using DNA primers pointing outward from the gentamycin cassette and DNA sequencing. Using this protocol, we have identified two novel alginate regulators, mucE (PA4033) and kinB (PA5484), in strain PAO1 with a wild-type mucA encoding the anti-sigma factor MucA for the master alginate regulator AlgU (AlgT, σ(22)). This high-throughput mutagenesis protocol can be modified for the identification of other virulence-related genes causing change in colony morphology.

Enhanced production of coenzyme Q10 by self-regulating the engineered MEP pathway in Rhodobacter sphaeroides.

Fine-tuning the expression level of an engineered pathway is crucial for the metabolic engineering of a host toward a desired phenotype. However, most engineered hosts suffer from nonfunctional protein expression, metabolic imbalance, cellular burden or toxicity from intermediates when an engineered pathway is first introduced, which can decrease production of the desired product. To circumvent these obstacles, we developed a self-regulation system utilizing the trc/tac promoter, LacI(q) protein and ribosomal binding sites (RBS). With the purpose of improving coenzyme Q10 (CoQ10 ) production by increasing the decaprenyl diphosphate supplement, enzymes DXS, DXR, IDI, and IspD were constitutively overexpressed under the control of the trc promoter in Rhodobacter sphaeroides. Then, a self-regulation system combining a set of RBSs for adjusting the expression of the LacI(q) protein was applied to tune the expression of the four genes, resulting in improved CoQ10 production. Finally, another copy of the tac promoter with the UbiG gene (involved in the ubiquinone pathway of CoQ10 biosynthesis) was introduced into the engineered pathway. By optimizing the expression level of both the upstream and downstream pathway, CoQ10 production in the mutants was improved up to 93.34 mg/L (7.16 mg/g DCW), about twofold of the wild-type (48.25 mg/L, 3.24 mg/g DCW).

Preclinical evaluation of a clinical candidate AAV8 vector for ornithine transcarbamylase (OTC) deficiency reveals functional enzyme from each persisting vector genome.

Ornithine transcarbamylase deficiency (OTCD), the most common and severe urea cycle disorder, is an excellent model for developing liver-directed gene therapy. No curative therapy exists except for liver transplantation which is limited by available donors and carries significant risk of mortality and morbidity. Adeno-associated virus 8 (AAV8) has been shown to be the most efficient vector for liver-directed gene transfer and is currently being evaluated in a clinical trial for treating hemophilia B. In this study, we generated a clinical candidate vector for a proposed OTC gene therapy trial in humans based on a self-complementary AAV8 vector expressing codon-optimized human OTC (hOTCco) under the control of a liver-specific promoter. Codon-optimization dramatically improved the efficacy of OTC gene therapy. Supraphysiological expression levels and activity of hOTC were achieved in adult spf(ash) mice following a single intravenous injection of hOTCco vector. Vector doses as low as 1×10(10) genome copies (GC) achieved robust and sustained correction of the OTCD biomarker orotic aciduria and clinical protection against an ammonia challenge. Functional expression of hOTC in 40% of liver areas was found in mice treated with a low vector dose of 1×10(9) GC. We suggest that the clinical candidate vector we have developed has the potential to achieve therapeutic effects in OTCD patients.

The roles of serum selenium and selenoproteins on mercury toxicity in environmental and occupational exposure.

Many studies have found that mercury (Hg) exposure is associated with selenium (Se) accumulation in vivo. However, human studies are limited. To study the interaction between Se and Hg, we investigated the total Se and Hg concentrations in body fluids and serum Se-containing proteins in individuals exposed to high concentrations of Hg. Our objective was to elucidate the possible roles of serum Se and selenoproteins in transporting and binding Hg in human populations. We collected data from 72 subjects: 35 had very low Hg exposure as evidenced by mean Hg concentrations of 0.91 and 1.25 ng/mL measured in serum and urine, respectively; 37 had high exposure (mean Hg concentrations of 38.5 and 86.8 ng/mL measured in serum and urine, respectively). An association between Se and Hg was found in urine (r = 0.625; p < 0.001) but not in serum. Hg exposure may affect Se concentrations and selenoprotein distribution in human serum. Expression of both selenoprotein P and glutathione peroxidase (GSH-Px) was greatly increased in Hg miners. These increases were accompanied by elevated Se concentrations in serum. In addition, selenoprotein P bound more Hg at higher Hg exposure concentrations. Biochemical observations revealed that both GSH-Px activity and malondialdehyde concentrations increased in serum of the Hg-exposed group. This study aids in the understanding of the interaction between Se and Hg. Selenoproteins play two important roles in protecting against Hg toxicity. First, they may bind more Hg through their highly reactive selenol group, and second, their antioxidative properties help eliminate the reactive oxygen species induced by Hg in vivo.

Molecular cloning, genomic organization, genetic variations, and characterization of murine sterolin genes Abcg5 and Abcg8.

Mammalian physiological processes can distinguish between dietary cholesterol and non-cholesterol, retaining very little of the non-cholesterol in their bodies. We have recently identified two genes, ABCG5 and ABCG8, encoding sterolin-1 and -2 respectively, mutations of which cause the human disease sitosterolemia. We report here the mouse cDNAs and genomic organization of Abcg5 and Abcg8. Both genes are arranged in an unusual head-to-head configuration, and only 140 bases separate their two respective start-transcription sites. A single TATA motif was identified, with no canonical CCAT box present between the two genes. The genes are located on mouse chromosome 17 and this complex spans no more than 40 kb. Expression of both genes is confined to the liver and intestine. For both genes, two different sizes of transcripts were identified which differ in the lengths of their 3' UTRs. Additionally, alternatively spliced forms for Abcg8 were identified, resulting from a CAG repeat at the intron 1 splice-acceptor site, causing a deletion of a glutamine. We screened 20 different mouse strains for polymorphic variants. Although a large number of polymorphic variants were identified, strains reported to show significant differences in cholesterol absorption rates did not show significant genomic variations in Abcg5 or Abcg8.