Photocatalytic Mechanism Regulation of Bismuth Oxyhalogen via Changing Atomic Assembly Method

Exciton and carrier photocatalytic processes have been proved in bismuth oxyhalogen photocatalysts. But, there are no reports about how to regulate the different mechanisms to improve photocatalytic activity for different reaction. Here, we found that the photocatalytic mechanisms could be regulated by changing the assembly method of bismuth, oxygen, and halogen atoms. Reactive oxygen species (ROS) experimentals results concluded that solid solution BiOBr_0.5I_0.5 showed enhanced exciton photocatalytic process, and coupling 0.5BiOBr/0.5BiOI displayed improved carrier photocatalytic proces. This work promoted the understanding about solid solution and coupling for bismuth oxyhalogen.

Envelope contributions to the representation of interaural time difference in the forebrain of barn owls

Birds and mammals use the interaural time difference (ITD) for azimuthal sound localization. While barn owls can use the ITD of the stimulus carrier frequency over nearly their entire hearing range, mammals have to utilize the ITD of the stimulus envelope to extend the upper frequency limit of ITD-based sound localization. ITD is computed and processed in a dedicated neural circuit that consists of two pathways. In the barn owl, ITD representation is more complex in the forebrain than in the midbrain pathway because of the combination of two inputs that represent different ITDs. We speculated that one of the two inputs includes an envelope contribution. To estimate the envelope contribution, we recorded ITD response functions for correlated and anticorrelated noise stimuli in the barn owl's auditory arcopallium. Our findings indicate that barn owls, like mammals, represent both carrier and envelope ITDs of overlapping frequency ranges, supporting the hypothesis that carrier and envelope ITD-based localization are complementary beyond a mere extension of the upper frequency limit.NEW & NOTEWORTHY The results presented in this study show for the first time that the barn owl is able to extract and represent the interaural time difference (ITD) information conveyed by the envelope of a broadband acoustic signal. Like mammals, the barn owl extracts the ITD of the envelope and the carrier of a signal from the same frequency range. These results are of general interest, since they reinforce a trend found in neural signal processing across different species.

A comparison of enriched culture and Xpert polymerase chain reaction assay of Group B streptococcus carrier status at 35-37-week gestation to labor onset: a prospective controlled study

OBJECTIVES

(1) To compare the accuracy of vagino-rectal enriched culture (EC) and a rapid polymerase chain reaction (PCR) test for the detection of Group B streptococcus (GBS) carrier status at 35-37-week gestation and at onset of labor. (2) To assess the conversion rate of GBS carrier status between 35-37 weeks to the onset of labor according to the EC/PCR tests. A prospective study was performed at a women's health clinic, referred to give birth at one medical center.

STUDY POPULATION

Low risk pregnant women at 35-37-week gestation who did not know their GBS carrier status.

METHODS

Participants were evaluated for GBS status both at 35-37 weeks and at labor onset. Correlation between tests was calculated by Spearman correlation.

RESULTS

One hundred and ten specimens were analyzed. Correlations: EC-PCR: 35-37 weeks - very high (r = 0.8), at labor - high (r = 0.5).

EC-EC

35-37 weeks and at labor - high (r = 0.39); PCR-PCR: 35-37 weeks and at labor- high (r = 0.7).

CONCLUSIONS

Both the EC and Xpert PCR tests are accurate for detecting GBS carrier, both at 35-37 weeks and at labor onset. We did not detect a significant conversion of the GBS status from negative at 35-37 weeks to positive at onset of labor.

Management of asymptomatic gene carriers of transthyretin familial amyloid polyneuropathy

Transthyretin familial amyloid polyneuropathy (TTR‐FAP) is a rare, severe, and irreversible, adult‐onset, hereditary disorder caused by autosomal‐dominant mutations in the TTR gene that increase the intrinsic propensity of transthyretin protein to misfold and deposit systemically as insoluble amyloid fibrils in nerve tissues, the heart, and other organs. TTR‐FAP is characterized by relentless, progressively debilitating polyneuropathy, and leads to death, on average, within 10 years of symptom onset without treatment. With increased availability of disease‐modifying treatment options for a wider spectrum of patients with TTR‐FAP, timely detection of the disease may offer substantial clinical benefits. This review discusses mutation‐specific predictive genetic testing in first‐degree relatives of index patients diagnosed with TTR‐FAP and the structured clinical follow‐up of asymptomatic gene carriers for prompt diagnosis and early therapeutic intervention before accumulation of substantial damage. Muscle Nerve54: 353–360, 2016

[Effect of Activated Carbon Addition on the Anaerobic Fermentation of Corn Straw in Mesophilic and Thermophilic Conditions]

In order to improve the methane production and concentration, effect of activated carbon addition on the anaerobic fermentation of corn straw under the conditions of mesophilic temperature (38℃) and thermophilic temperature(50℃) was investigated in this study. The results showed that the addition of activated carbon could significantly promote methane production. Compared with the control group in mesophilic and thermophilic conditions, cumulative methane production could be increased by 63% and 96% in test groups. By DGGE analysis, the bacterium enriched by addition of activated carbon was mainly Clostridiales bacterium, compared to Bacillus (without adding activated carbon) in the thermophilic system, while the differences in fermentation with adding activated carbon and without adding activated carbon was not significant in the mesophilic system. With addition of activated carbon, the archaea enriched in the fermentation liquid was mainly Methanosaeta concilii in the mesophilic system, whereas the archaea enriched in the fermentation liquid was mainly Methanosarcina acetivorans in the thermophilic system. The archaea enriched on activated carbon was mainly Methanosaeta concilii at mesophilic temperature, while the archaea enriched on activated carbon was mainly Methanosarcina thermophila at thermophilic temperature.

Functional Properties of the Mitochondrial Carrier System

The mitochondrial carrier system (MCS) transports small molecules between mitochondria and the cytoplasm. It is integral to the core mitochondrial function to regulate cellular chemistry by metabolism. The mammalian MCS comprises the transporters of the 53-member canonical SLC25A family and a lesser number of identified noncanonical transporters. The recent discovery and investigations of the mitochondrial pyruvate carrier (MPC) illustrate the diverse effects a single mitochondrial carrier may exert on cellular function. However, the transport selectivities of many carriers remain unknown, and most have not been functionally investigated in mammalian cells. The mechanisms coordinating their function as a unified system remain undefined. Increased accessibility to molecular genetic and metabolomic technologies now greatly enables investigation of the MCS. Continued investigation of the MCS may reveal how mitochondria encode complex regulatory information within chemical thermodynamic gradients. This understanding may enable precision modulation of cellular chemistry to counteract the dysmetabolism inherent in disease.

Increased Pilus Production Conferred by a Naturally Occurring Mutation Alters Host-Pathogen Interaction in Favor of Carriage in Streptococcus pyogenes

Studies of the human pathogen group A Streptococcus (GAS) define the carrier phenotype to be an increased ability to adhere to and persist on epithelial surfaces and a decreased ability to cause disease. We tested the hypothesis that a single amino acid change (Arg135Gly) in a highly conserved sensor kinase (LiaS) of a poorly defined GAS regulatory system contributes to a carrier phenotype through increased pilus production. When introduced into an emm serotype-matched invasive strain, the carrier allele (the gene encoding the LiaS protein with an arginine-to-glycine change at position 135 [liaS^R135G]) recapitulated a carrier phenotype defined by an increased ability to adhere to mucosal surfaces and a decreased ability to cause disease. Gene transcript analyses revealed that the liaS mutation significantly altered transcription of the genes encoding pilus in the presence of bacitracin. Elimination of pilus production in the isogenic carrier mutant decreased its ability to colonize the mouse nasopharynx and to adhere to and be internalized by cultured human epithelial cells and restored the virulence phenotype in a mouse model of necrotizing fasciitis. We also observed significantly reduced survival of the isogenic carrier mutant compared to that of the parental invasive strain after exposure to human neutrophils. Elimination of pilus in the isogenic carrier mutant increased the level of survival after exposure to human neutrophils to that for the parental invasive strain. Together, our data demonstrate that the carrier mutation (liaS^R135G) affects pilus expression. Our data suggest new mechanisms of pilus gene regulation in GAS and that the invasiveness associated with pilus gene regulation in GAS differs from the enhanced invasiveness associated with increased pilus production in other bacterial pathogens.

Pre-natal diagnosis of thalassaemia in Sri Lanka: A ten year review

Thalassaemia is the commonest monogenic disease in Sri Lanka, affecting over 3500 children and half-a-million thalassaemia carriers. This is a review of 82 amniocenteses performed from 2006 to 2016, in the largest prenatal diagnoses study for thalassaemia carried out in Sri Lanka. Amniocenteses were performed between 11 and 12 weeks of ultrasonically confirmed gestation, on mothers with previous thalassaemia major children pregnant for the second time and nulliparous thalassaemia trait women married to trait partners. The Consultant Radiologist, using local analgesia, under ultrasound cover, performed these as an outpatient procedure, at the Teaching Hospital Kandy & Suwasevana Hospital Kandy. The amniotic fluid was analysed by the team of Senior Geneticists, at the Genetech Molecular Diagnostics and School of Gene Technology, Colombo, via the polymerase-chain-reaction based ARMS (Amplification Refractory Mutation Systems) assay. The genetic results indicated the presence of 21% thalassaemia major foetuses, 53% thalassaemia traits and 26% foetuses without thalassaemia mutations. The predominance of the IVS1-5(G-C) mutation in the Sri Lankan population is exemplified, with a low prevalence of HbE thalassaemia. Impact statement Thalassaemia is the commonest monogenic disease in Sri Lanka affecting over 3500 children and half-a-million thalassaemia carriers. Although pre-natal diagnosis by amniocentesis was practised universally for many years, this could not be performed in Sri Lanka as genetic diagnostic facilities were not available until 2005. Therefore, parents with a thalassaemia major child limited their families to one child, by choice or by termination. The results of this study point to a 21% probability of thalassaemia major in the next child, giving the parents a guarded optimism to conceive another child without thalassaemia disease. With siblings being the highest HLA compatibility for Bone Marrow Transplant, that is now being established in Sri Lanka as a permanent cure for thalassaemia, this will bring a ray of hope for these desperate parents to finally cure their previous sick child. Although, 95% of the Sri Lankan mutated genetic sites for thalassaemia are known, more research will be needed to identify the other rare sites. The publication of this paper, with its novelty for pre-natal diagnosis, would encourage clinicians to practice it in other centres and to extend it to families with other genetic disorders.

[Feasibility of an injectable and in situ gelling gelatin hydrogel for demineralized bone matrix powder delivery]

Objective

To introduce an injectable and in situ gelling gelatin hydrogel, and to explore the possibility as a carrier for demineralized bone matrix (DBM) powder delivery.

Methods

First, thiolated gelatin was prepared and the thiol content was determined by Ellman method, and then the injectable and in situ gelling gelatin hydrogel (Gel) was formed by crosslinking of the thiolated gelatin and poly (ethylene oxide) diacrylate and the gelation time was determined by inverted method. Finally, the DBM-Gel composite was prepared by mixing Gel and DBM powder. The cytotoxicity was tested by live/dead staining and Alamar blue assay of the encapsulated cells in the DBM-Gel. For in vitro cell induction, C2C12 cells were firstly incubated onto the surface of the DBM and then the composite was prepared. The experiment included two groups: DBM-Gel and DBM. The alkaline phosphatase (ALP) activity was determined at 1, 3, 5, and 7 days after culture. In vivo osteoinductivity was evaluated using ectopic bone formation model of nude rats. Histological observation and the ALP activity was measured in DBM-Gel and DBM groups at 4 weeks after implantation.

Results

The thiol content in the thiolated gelatin was (0.51±0.03) mmol/g determined by Ellman method. The gelation time of the hydrogel was (6±1) minutes. DBM powder can be mixed with the hydrogel and injected into the implantation site within the gelation time. The cells in the DBM-Gel exhibited spreading morphology and connected each other in part with increasing culture time. The viability of the cells was 95.4%±1.9%, 97.3%±1.3%, and 96.1%±1.6% at 1, 3, and 7 days after culture, respectively. The relative proliferation was 1.0±0.0, 1.1±0.1, 1.5±0.1, and 1.6±0.1 at 1, 3, 5, and 7 days after culture respectively. In vitro induction showed that the ALP activity of the DBM-Gel group was similar to that of the DBM group, showing no significant difference ( P>0.05). With increasing culture time, the ALP activities in both groups increased gradually and the activity at 5 and 7 days was significantly higher than that at 1 and 3 days ( P<0.05), while there was no significant difference between at 1 and 3 days, and between 5 and 7 days ( P>0.05). At 4 weeks after implantation in vivo, new bone and cartilage were observed, but no bone marrow formation in DBM-Gel group; in DBM group, new bone, new cartilage, and bone marrow formation were observed. The histological osteoinduction scores of DBM-Gel and DBM groups were 4.0 and 4.5, respectively. The ALP activities of DBM-Gel and DBM groups were respectively (119.4±22.7) and (146.7±13.0) μmol/mg protein/min, showing no significant difference ( t=-2.085, P=0.082).

Conclusion

The injectable and in situ gelling gelatin hydrogel for delivery of DBM is feasible.

The complex of PAMAM-OH dendrimer with Angiotensin (1-7) prevented the disuse-induced skeletal muscle atrophy in mice

Angiotensin (1–7) (Ang-(1–7)) is a bioactive heptapeptide with a short half-life and has beneficial effects in several tissues – among them, skeletal muscle – by preventing muscle atrophy. Dendrimers are promising vehicles for the protection and transport of numerous bioactive molecules. This work explored the use of a neutral, non-cytotoxic hydroxyl-terminated poly(amidoamine) (PAMAM-OH) dendrimer as an Ang-(1–7) carrier. Bioinformatics analysis showed that the Ang-(1–7)-binding capacity of the dendrimer presented a 2:1 molar ratio. Molecular dynamics simulation analysis revealed the capacity of neutral PAMAM-OH to protect Ang-(1–7) and form stable complexes. The peptide coverage ability of the dendrimer was between ~50% and 65%. Furthermore, an electrophoretic mobility shift assay demonstrated that neutral PAMAM-OH effectively bonded peptides. Experimental results showed that the Ang-(1–7)/PAMAM-OH complex, but not Ang-(1–7) alone, had an anti-atrophic effect when administered intraperitoneally, as evaluated by muscle strength, fiber diameter, myofibrillar protein levels, and atrogin-1 and MuRF-1 expressions. The results of the Ang-(1–7)/PAMAM-OH complex being intraperitoneally injected were similar to the results obtained when Ang-(1–7) was systemically administered through mini-osmotic pumps. Together, the results suggest that Ang-(1–7) can be protected for PAMAM-OH when this complex is intraperitoneally injected. Therefore, the Ang-(1–7)/PAMAM-OH complex is an efficient delivery method for Ang-(1–7), since it improves the anti-atrophic activity of this peptide in skeletal muscle.

Quantitative characteristics of the foot-and-mouth disease carrier state under natural conditions in India

The goal of this study was to characterize the properties and duration of the foot-and-mouth disease (FMD) carrier state and associated serological responses subsequent to vaccination and naturally occurring infection at two farms in northern India. Despite previous vaccination of cattle in these herds, clinical signs of FMD occurred in October 2013 within a subset of animals at the farms containing juvenile-yearling heifers and steers (Farm A) and adult dairy cattle (Farm B). Subsequent to the outbreak, FMD virus (FMDV) asymptomatic carriers were identified in both herds by seroreactivity to FMDV non-structural proteins and detection of FMDV genomic RNA in oropharyngeal fluid. Carriers' seroreactivity and FMDV genome detection status were subsequently monitored monthly for 23 months. The mean extinction time of the carrier state was 13.1 ± 0.2 months, with extinction having occurred significantly faster amongst adult dairy cattle at Farm B compared to younger animals at Farm A. The rate of decrease in the proportion of carrier animals was calculated to be 0.07 per month. Seroprevalence against FMDV non-structural proteins decreased over the course of the study period, but was found to increase transiently following repeated vaccinations. These data provide novel insights into viral and host factors associated with the FMDV carrier state under natural conditions. The findings reported herein may be relevant to field veterinarians and governmental regulatory entities engaged in FMD response and control measures.

Polypyrrole-Grafted Coconut Shell Biological Carbon as a Potential Adsorbent for Methyl Tert-Butyl Ether Removal: Characterization and Adsorption Capability

Methyl tert-butyl ether (MTBE) has been used as a common gasoline additive worldwide since the late twentieth century, and it has become the most frequently detected groundwater pollutant in many countries. This study aimed to synthesize a novel microbial carrier to improve its adsorptive capacity for MTBE and biofilm formation, compared to the traditional granular activated carbon (GAC). A polypyrrole (PPy)-modified GAC composite (PPy/GAC) was synthesized, and characterized by Fourier transform infrared spectroscopy (FT-IR) and Brunauer-Emmett-Teller (BET) surface area analysis. The adsorption behaviors of MTBE were well described by the pseudo-second-order and Langmuir isotherm models. Furthermore, three biofilm reactors were established with PPy/GAC, PPy, and GAC as the carriers, respectively, and the degradation of MTBE under continuous flow was investigated. Compared to the biofilm reactors with PPy or GAC (which both broke after a period of operation), the PPy/GAC biofilm column produced stable effluents under variable treatment conditions with a long-term effluent MTBE concentration <20 μg/L. Pseudomonas aeruginosa and Acinetobacter pittii may be the predominant bacteria responsible for MTBE degradation in these biofilm reactors.

Renal targeting potential of a polymeric drug carrier, poly-l-glutamic acid, in normal and diabetic rats

BACKGROUND AND PURPOSE

Poly-l-glutamic acid (PG) has been used widely as a carrier to deliver anticancer chemotherapeutics. This study evaluates PG as a selective renal drug carrier.

EXPERIMENTAL APPROACH

3H-deoxycytidine-labeled PGs (17 or 41 kDa) and 3H-deoxycytidine were administered intravenously to normal rats and streptozotocin-induced diabetic rats. The biodistribution of these compounds was determined over 24 h. Accumulation of PG in normal kidneys was also tracked using 5-(aminoacetamido) fluorescein (fluoresceinyl glycine amide)-labeled PG (PG-AF). To evaluate the potential of PGs in ferrying renal protective anti-oxidative stress compounds, the model drug 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF) was conjugated to 41 kDa PG to form PG-AEBSF. PG-AEBSF was then characterized and evaluated for intracellular anti-oxidative stress efficacy (relative to free AEBSF).

RESULTS

In the normal rat kidneys, 17 kDa radiolabeled PG (PG-Tr) presents a 7-fold higher, while 41 kDa PG-Tr shows a 15-fold higher renal accumulation than the free radiolabel after 24 h post injection. The accumulation of PG-AF was primarily found in the renal tubular tissues at 2 and 6 h after an intravenous administration. In the diabetic (oxidative stress-induced) kidneys, 41 kDa PG-Tr showed the greatest renal accumulation of 8-fold higher than the free compound 24 h post dose. Meanwhile, the synthesized PG-AEBSF was found to inhibit intracellular nicotinamide adenine dinucleotide phosphate oxidase (a reactive oxygen species generator) at an efficiency that is comparable to that of free AEBSF. This indicates the preservation of the anti-oxidative stress properties of AEBSF in the conjugated state.

CONCLUSION/IMPLICATIONS

The favorable accumulation property of 41 kDa PG in normal and oxidative stress-induced kidneys, along with its capabilities in conserving the pharmacological properties of the conjugated renal protective drugs, supports its role as a potential renal targeting drug carrier.

Polyethylene glycol as a promising synthetic material for repair of spinal cord injury

Polyethylene glycol is a synthetic, biodegradable, and water-soluble polyether. Owing to its good biological and material properties, polyethylene glycol shows promise in spinal cord tissue engineering applications. Although studies have examined repairing spinal cord injury with polyethylene glycol, these compelling findings have not been recently reviewed or evaluated as a whole. Thus, we herein review and summarize the findings of studies conducted both within and beyond China that have examined the repair of spinal cord injury using polyethylene glycol. The following summarizes the results of studies using polyethylene glycol alone as well as coupled with polymers or hydrogels: (1) polyethylene glycol as an adjustable biomolecule carrier resists nerve fiber degeneration, reduces the inflammatory response, inhibits vacuole and scar formation, and protects nerve membranes in the acute stage of spinal cord injury. (2) Polyethylene glycol-coupled polymers not only promote angiogenesis but also carry drugs or bioactive molecules to the injury site. Because such polymers cross both the blood-spinal cord and blood-brain barriers, they have been widely used as drug carriers. (3) Polyethylene glycol hydrogels have been used as supporting substrates for the growth of stem cells after injury, inducing cell migration, proliferation, and differentiation. Simultaneously, polyethylene glycol hydrogels isolate or reduce local glial scar invasion, promote and guide axonal regeneration, cross the transplanted area, and re-establish synaptic connections with target tissue, thereby promoting spinal cord repair. On the basis of the reviewed studies, we conclude that polyethylene glycol is a promising synthetic material for use in the repair of spinal cord injury.

Prevalence of Salmonella Excretion in Stool: A Community Survey in 2 Sites, Guinea-Bissau and Senegal

BACKGROUND

Chronic and convalescent carriers play an important role in the transmission and endemicity of many communicable diseases. A high incidence of Salmonella enterica serovar Typhi and invasive nontyphoidal Salmonella (NTS) infection has been reported in parts of sub-Saharan Africa, yet the prevalence of Salmonella excretion in the general population is unknown.

METHODS

Stool specimens were collected from a random sample of households in 2 populations in West Africa: Bissau, Guinea-Bissau, and Dakar, Senegal. Stool was cultured to detect presence of Salmonella, and antimicrobial susceptibility testing was performed on the isolated organisms.

RESULTS

Stool was cultured from 1077 and 1359 individuals from Guinea-Bissau and Senegal, respectively. Salmonella Typhi was not isolated from stool samples at either site. Prevalence of NTS in stool samples was 24.1 (95% confidence interval [CI], 16.5-35.1; n = 26/1077) per 1000 population in Guinea-Bissau and 10.3 (95% CI, 6.1-17.2; n = 14/1359) per 1000 population in Senegal.

CONCLUSIONS

Evidence of NTS excretion in stool in both study populations indicates a possible NTS transmission route in these settings.

Detection of Clostridium difficile in Feces of Asymptomatic Patients Admitted to the Hospital

Recent evidence shows that patients asymptomatically colonized with Clostridium difficile may contribute to the transmission of C. difficile in health care facilities. Additionally, these patients may have a higher risk of developing C. difficile infection. The aim of this study was to compare a commercially available PCR directed to both toxin A and B (artus C. difficile QS-RGQ kit CE; Qiagen), an enzyme-linked fluorescent assay to glutamate dehydrogenase (GDH ELFA) (Vidas, bioMérieux), and an in-house-developed PCR to tcdB, with (toxigenic) culture of C. difficile as the gold standard to detect asymptomatic colonization. Test performances were evaluated in a collection of 765 stool samples obtained from asymptomatic patients at admission to the hospital. The C. difficile prevalence in this collection was 5.1%, and 3.1% contained toxigenic C. difficile Compared to C. difficile culture, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the C. difficile GDH ELFA were 87.2%, 91.2%, 34.7%, and 99.3%, respectively. Compared with results of toxigenic culture, the sensitivity, specificity, PPV, and NPV of the commercially available PCR and the in-house PCR were 95.8%, 93.4%, 31.9%, 99.9%, and 87.5%, 98.8%, 70%, and 99.6%, respectively. We conclude that in a low-prevalence setting of asymptomatically colonized patients, both GDH ELFA and a nucleic acid amplification test can be applied as a first screening test, as they both display a high NPV. However, the low PPV of the tests hinders the use of these assays as stand-alone tests.

A Facile Strategy to Prepare Hyperbranched Hydroxyl-Rich Polycations for Effective Gene Therapy

For effective gene therapy, nonviral gene carriers with low toxicity and high transfection efficiency are of much importance. In this work, we developed a facile strategy to prepare hyperbranched hydroxyl-rich polycations (denoted by TE) by the one-pot method involving ring-opening reactions between two commonly used reagents, ethylenediamine (ED) with two amino groups and 1,3,5-triglycidyl isocyanurate (TGIC) with three epoxy groups. The hyperbranched TEs with different molecular weights were investigated on their DNA condensation ability, protein absorption property, biocompatibility, transfection efficiency, and in vivo cancer therapy and toxicity. TE exhibited low cytotoxicity and protein absorption property due to the plentiful hydroxyl groups. The optimal transfection efficiency of TE was significantly higher than that of the gold standard polycationic gene carrier branched polyethylenimine (PEI, 25 kDa). Furthermore, TE was applied for in vivo tumor inhibition by the delivery of antioncogene p53, which showed good antitumor efficiency with low adverse effects. The present work provides a new concept for the facile preparation of hyperbranched hydroxyl-rich polycationic carriers with good transfection performances.

New formulation and delivery method of Cryphonectria parasitica for biological control of chestnut blight

AIMS

This study aimed to develop a new formulation of Cryphonectria parasitica hypovirulent mycelium suitable for inoculations of tall trees from the ground. Cryphonectria parasitica hypovirulent strains are widely used for biological control of chestnut blight. However, it is often inconsistent and ineffective not only for biological reasons but also because the current manual application of hypovirulent strains on adult plants is difficult, time-consuming and expensive. Here, we propose an improved formulation and more effective mode of application of hypovirulent strains, which could boost chestnut blight biocontrol.

METHODS AND RESULTS

The Cp 4.2H hypovirulent strain was formulated as mycelium discs with polyethylene glycol and hydroxypropyl methylcellulose, loaded into lead-free pellets that are used as carriers to inoculate cankers on chestnut stems by shooting. The formulation of mycelium did not hamper its viability which was stable, with an estimated shelf life of 72 days at 6 ± 1°C. The inoculum effectiveness was confirmed ex planta and in planta in a small-scale pilot study in field, where formulated mycelium discs of hypovirulent strain Cp 4.2H were inoculated by airgun shot method into the chestnut bark. In planta, Cp 4.2H was recovered in 37% of bark samples taken around the inoculated points 1 year after the treatment.

CONCLUSIONS

We demonstrated that the proposed airgun shooting inoculation method of C. parasitica hypovirulent strain formulated as mycelium discs is suitable for treatment of adult chestnut trees.

SIGNIFICANCE AND IMPACT OF THE STUDY

The proposed method could be a valid alternative to the traditional manual technique of chestnut biocontrol. The main advantages are the cost-effectiveness and the ease to treat high-positioned, otherwise unreachable cankers both in orchards and forests.

Biomaterials to Facilitate Delivery of RNA Agents in Bone Regeneration and Repair

Bone healing after traumatic injuries or pathological diseases remains an important worldwide problem. In search of safer and more effective approaches to bone regeneration and repair, RNA-based therapeutic agents, specifically microRNAs (miRNAs) and short interfering RNA (siRNA), are beginning to be actively explored. In this review, we summarize current attempts to employ miRNAs and siRNAs in preclinical models of bone repair. We provide a summary of current limitations when attempting to utilize bioactive nucleic acids for therapeutic purposes and position the unique aspects of RNA reagents for clinical bone repair. Delivery strategies for RNA reagents are emphasized and nonviral carriers (biomaterial-based) employed to deliver such reagents are reviewed. Critical features of biomaterial carriers and various delivery technologies centered around nanoparticulate systems are highlighted. We conclude with the authors' perspectives on the future of the field, outlining main critical issues important to address as RNA reagents are explored for clinical applications.

Carbon nanotubes as cancer therapeutic carriers and mediators

Carbon nanotubes (CNTs) have received increasing attention in biomedical fields because of their unique structures and properties, including high aspect ratios, large surface areas, rich surface chemical functionalities, and size stability on the nanoscale. Particularly, they are attractive as carriers and mediators for cancer therapy. Through appropriate functionalization, CNTs have been used as nanocarriers for anticancer drugs including doxorubicin, camptothecin, carboplatin, cisplatin, paclitaxel, Pt(II), and Pt(IV), and genes including plasmid DNA, small-interfering RNA, oligonucleotides, and RNA/DNA aptamers. CNTs can also deliver proteins and immunotherapy components. Using combinations of light energy, they have also been applied as mediators for photothermal therapy and photodynamic therapy to directly destroy cancer cells without severely damaging normal tissue. If limitations such as a long-term cytotoxicity in the body, lack of size uniformity during the synthetic process, loading deviations for drug–CNT complexes, and release controllability at the target point are overcome, CNTs will become one of the strongest tools that are available for various other biomedical fields as well as for cancer therapy.

An Evaluation of Quantitative PCR Assays (TaqMan® and SYBR Green) for the Detection of Babesia bigemina and Babesia bovis, and a Novel Fluorescent-ITS1-PCR Capillary Electrophoresis Method for Genotyping B. bovis Isolates

Babesia spp. are tick-transmitted haemoparasites causing tick fever in cattle. In Australia, economic losses to the cattle industry from tick fever are estimated at AUD$26 Million per annum. If animals recover from these infections, they become immune carriers. Here we describe a novel multiplex TaqMan qPCR targeting cytochrome b genes for the identification of Babesia spp. The assay shows high sensitivity, specificity and reproducibility, and allows quantification of parasite DNA from Babesia bovis and B. bigemina compared to standard PCR assays. A previously published cytochrome b SYBR Green qPCR was also tested in this study, showing slightly higher sensitivity than the Taqman qPCRs but requires melting curve analysis post-PCR to confirm specificity. The SYBR Green assays were further evaluated using both diagnostic submissions and vaccinated cattle (at 7, 9, 11 and 14 days post-inoculation) showed that B. bigemina can be detected more frequently than B. bovis. Due to fewer circulating parasites, B. bovis detection in carrier animals requires higher DNA input. Preliminary data for a novel fluorescent PCR genotyping based on the Internal Transcribed Spacer 1 region to detect vaccine and field alleles of B. bovis are described. This assay is capable of detecting vaccine and novel field isolate alleles in a single sample.

Core-Shell Soy Protein-Soy Polysaccharide Complex (Nano)particles as Carriers for Improved Stability and Sustained Release of Curcumin

Using soy protein isolate (SPI) and soy-soluble polysaccharides (SSPS) as polymer matrixes, this study reported a novel process to fabricate unique core-shell complex (nano)particles to perform as carriers for curcumin (a typical poorly soluble bioactive). In the process, curcumin-SPI nanocomplexes were first formed at pH 7.0 and then coated by SSPS. At this pH, the core-shell complex was formed in a way the SPI nanoparticles might be incorporated into the interior of SSPS molecules without distinctly affecting the size and morphology of particles. The core-shell structure was distinctly changed by adjusting pH from 7.0 to 4.0. At pH 4.0, SSPS was strongly bound to the surface of highly aggregated SPI nanoparticles, and as a consequence, much larger complexes were formed. The bioaccessibility of curcumin in the SPI-curcumin complexes was unaffected by the SSPS coating. However, the core-shell complex formation greatly improved the thermal stability and controlled release properties of encapsulated curcumin. The improvement was much better at pH 4.0 than that at pH 7.0. All of the freeze-dried core-shell complex preparations exhibited good redispersion behavior. The findings provide a simple approach to fabricate food-grade delivery systems for improved water dispersion, heat stability, and even controlled release of poorly soluble bioactives.

Targeted sequencing of BRCA1 and BRCA2 across a large unselected breast cancer cohort suggests that one-third of mutations are somatic

We carried out targeted sequencing of BRCA1/2 in an unselected cohort of patients diagnosed with primary breast cancer within a population without strong founder mutations. Eleven percent of cases harbored a germline or somatic BRCA1/2 mutation, and the ratio of germline versus somatic mutation was 2 : 1. This has implications for treatment, genetic counseling, and interpretation of tumor-only testing.

Background

A mutation found in the BRCA1 or BRCA2 gene of a breast tumor could be either germline or somatically acquired. The prevalence of somatic BRCA1/2 mutations and the ratio between somatic and germline BRCA1/2 mutations in unselected breast cancer patients are currently unclear.

Patients and methods

Paired normal and tumor DNA was analyzed for BRCA1/2 mutations by massively parallel sequencing in an unselected cohort of 273 breast cancer patients from south Sweden.

Results

Deleterious germline mutations in BRCA1 (n = 10) or BRCA2 (n = 10) were detected in 20 patients (7%). Deleterious somatic mutations in BRCA1 (n = 4) or BRCA2 (n = 5) were detected in 9 patients (3%). Accordingly, about 1 in 9 breast carcinomas (11%) in our cohort harbor a BRCA1/2 mutation. For each gene, the tumor phenotypes were very similar regardless of the mutation being germline or somatically acquired, whereas the tumor phenotypes differed significantly between wild-type and mutated cases. For age at diagnosis, the patients with somatic BRCA1/2 mutations resembled the wild-type patients (median age at diagnosis, germline BRCA1: 41.5 years; germline BRCA2: 49.5 years; somatic BRCA1/2: 65 years; wild-type BRCA1/2: 62.5 years).

Conclusions

In a population without strong germline founder mutations, the likelihood of a BRCA1/2 mutation found in a breast carcinoma being somatic was ∼1/3 and germline 2/3. This may have implications for treatment and genetic counseling.

Genetic Diversity among Group A Streptococcus Isolated from Throats of Healthy and Symptomatic Children

BACKGROUND

Group A streptococcus (GAS) is the commonest bacterial cause of pharyngitis. Children in the age group of 5-15 years are most commonly affected. It can also colonize throats of healthy children in this age group. Both cases and carriers can transmit it in the community.

METHODS

Throat swab samples were collected from 1849 asymptomatic and 371 symptomatic children.

RESULTS

The rate of isolation of GAS was 1.41% among the asymptomatic group and 7.55% among the symptomatic group. Nine different emm types were encountered in the asymptomatic children and 14 among the symptomatic children.

CONCLUSION

Throat swab cultures must be used in all cases of pharyngitis. Early and appropriate antibiotic therapy will prevent complications. Asymptomatic throat carriage of GAS in children was low in our study. However, they can still act as reservoirs. Emm typing helps in understanding epidemiology and finding new types.

Surveillance for Pasteurella multocida in Ring-Necked Pheasants (Phasianus colchicus) After an Outbreak of Avian Cholera and Apparently Successful Antibiotic Treatment

Avian cholera is a significant disease of domestic and wild birds caused by the bacterium Pasteurella multocida (PM). In poultry, a major source of PM infection is chronic carriers, domestic birds that have become infected and recovered or had subclinical infections. Although outbreaks of avian cholera in ring-necked pheasants (Phasianus colchicus) have been reported, the potential for chronic carriers is unknown. To address this, we conducted surveillance for PM in a flock of captive ring-necked pheasants after an outbreak of avian cholera that responded positively to antibiotic treatment based on resolution of morbidity and mortality. At approximately 1 mo after antibiotic treatment, oropharyngeal swabs were collected from 300 pheasants (out of a total population of ~2300) in a single winter holding pen. All samples were tested for PM through routine aerobic bacterial culture, but none of the samples were positive. In addition, there were no additional outbreaks within this infected pen over the subsequent months. These data provide preliminary evidence to suggest that pheasants that respond to antibiotic therapy may be less likely to become chronic carriers of PM than other poultry species, such as chickens (Gallus domesticus). However, due to marked phenotypic and biologic differences between PM strains, additional studies are needed to further support or refute these findings and better understand avian cholera in this species.