Light activated antimicrobial agents can inactivate oral malodour causing bacteria.

Oral malodour is a common condition which affects a large proportion of the population, resulting in social, emotional and psychological stress. Certain oral bacteria form a coating called a biofilm on the tongue dorsum and degrade organic compounds releasing volatile sulfur compounds that are malodourous. Current chemical treatments for oral malodour such as mouthwashes containing chlorhexidine or essential oils, are not sufficiently effective at reducing the bacterial load on the tongue. One potential alternative to current chemical treatments for oral malodour is the use of light activated antimicrobial agents (LAAAs), which display no toxicity or antimicrobial activity in the dark, but when exposed to light of a specific wavelength produce reactive oxygen species which induce damage to target cells in a process known as photodynamic inactivation. This study aimed to determine whether oral malodour causing bacteria were susceptible to lethal photosensitization. Five bacterial species that are causative agents of oral malodour were highly sensitive to lethal photosensitization and were efficiently killed by methylene blue in conjunction with 665 nm laser light. Between 4.5-5 log10 reductions in the number of viable bacteria were achieved with 20 µM methylene blue and 14.53 J cm(-2) laser light for Porphyromonas gingivalis, Prevotella intermedia, Peptostreptococcus anaerobius and Solobacterium moorei. The number of viable cells fell below the limit of detection in the case of Fusobacterium nucleatum. These findings demonstrate that methylene blue in combination with 665 nm laser light is effective at killing bacteria associated with oral malodour, suggesting photodynamic therapy could be a viable treatment option for oral malodour

Evidence of the Generation of Isosaccharinic Acids and Their Subsequent Degradation by Local Microbial Consortia within Hyper-Alkaline Contaminated Soils, with Relevance to Intermediate Level Radioactive Waste Disposal

The contamination of surface environments with hydroxide rich wastes leads to the formation of high pH (>11.0) soil profiles. One such site is a legacy lime works at Harpur Hill, Derbyshire where soil profile indicated in-situ pH values up to pH 12. Soil and porewater profiles around the site indicated clear evidence of the presence of the α and β stereoisomers of isosaccharinic acid (ISA) resulting from the anoxic, alkaline degradation of cellulosic material. ISAs are of particular interest with regards to the disposal of cellulosic materials contained within the intermediate level waste (ILW) inventory of the United Kingdom, where they may influence radionuclide mobility via complexation events occurring within a geological disposal facility (GDF) concept. The mixing of uncontaminated soils with the alkaline leachate of the site resulted in ISA generation, where the rate of generation in-situ is likely to be dependent upon the prevailing temperature of the soil. Microbial consortia present in the uncontaminated soil were capable of surviving conditions imposed by the alkaline leachate and demonstrated the ability to utilise ISAs as a carbon source. Leachate-contaminated soil was sub-cultured in a cellulose degradation product driven microcosm operating at pH 11, the consortia present were capable of the degradation of ISAs and the generation of methane from the resultant H2/CO2 produced from fermentation processes. Following microbial community analysis, fermentation processes appear to be predominated by Clostridia from the genus Alkaliphilus sp, with methanogenesis being attributed to Methanobacterium and Methanomassiliicoccus sp. The study is the first to identify the generation of ISA within an anthropogenic environment and advocates the notion that microbial activity within an ILW-GDF is likely to influence the impact of ISAs upon radionuclide migration

Dynamics of HEV viremia, fecal shedding and its relationship with transaminases and antibody response in patients with sporadic acute hepatitis E

<p>Abstract</p> <p>Background</p> <p>There is paucity of data regarding duration of fecal excretion and viremia on sequential samples from individual patients and its correlation with serum transaminases and antibody responses in patients with acute hepatitis E. This prospective study was undertaken at a tertiary care center in Northern India over 15 months. Only those patients of sporadic acute hepatitis E who were in their first week of illness and followed up weekly for liver function tests, IgM anti HEV antibody and HEV RNA in sera and stool were included. HEV RNA was done by RT - nPCR using two pairs of primers from RdRp region of ORF 1 of the HEV genome.</p> <p>Results</p> <p>Over a period of 15 months 60 patients met the inclusion criterion and were enrolled for the final analysis. The mean age of the patients was 29.2 ± 8.92 years, there were 39 males. The positivity of IgM anti HEV was 80% at diagnosis and 18.3% at 7th week, HEV RNA 85% at diagnosis and 6.6% at 7th week and fecal RNA 70% at the time of diagnosis and 20% at 4th week. The maximum duration of viremia detected was 42 days and fecal viral shedding was 28 days after the onset of illness.</p> <p>Conclusion</p> <p>Present study reported HEV RNA positivity in sera after normalization of transaminases. Fecal shedding was not seen beyond normalization of transaminases. However, viremia lasted beyond normalization of transaminases suggesting that liver injury is independent of viral replication.</p

Evaluation of the utilization of the preanaesthetic clinics in a University teaching hospital

BACKGROUND: Dedicated out-patient preanaesthetic clinics are relatively recent phenomenon and information is sparse from developing world. This study attempted to evaluate the utilization of adult and paediatric preanaesthetic clinics and its impact on the cancellations of surgery in Trinidad. METHODS: All patients scheduled to have elective surgery during the period of twelve weeks were enrolled for prospective collection of data including demographics, the admitting diagnoses, surgical procedure, category of surgery and specialty, and the patients' attendance to preanaesthetic clinics. Cancellations on the day of surgery along with reasons were recorded. The difference between patients who attended and did not attend the clinic was analysed. RESULTS: Of 424 patients scheduled for procedures during the study period, 213 were adults and 211 were children. Overall 39% of adults and 46% of the children scheduled for surgery had previously attended the preanaesthetic clinic. Among adults, general surgery patients were the largest majority to attend the preanaesthetic clinic. The paediatric preanaesthetic clinic was mostly utilized by paediatric general surgery. Overall 30% of procedures in adults and 26% of those in children were cancelled. There was a statistically significant difference in cancellations between patients who attended and did not attend the preanaesthetic clinic (p = 0.004). There was a 52% more chance of the procedure getting cancelled if the patient did not attend the clinic. CONCLUSION: The study highlights the inadequate use of the preanaesthetic clinics and the impact of the clinics on last-minute cancellations

Two Theileria parva CD8 T Cell Antigen Genes Are More Variable in Buffalo than Cattle Parasites, but Differ in Pattern of Sequence Diversity

&lt;p&gt;&lt;b&gt;Background:&lt;/b&gt; Theileria parva causes an acute fatal disease in cattle, but infections are asymptomatic in the African buffalo (Syncerus caffer). Cattle can be immunized against the parasite by infection and treatment, but immunity is partially strain specific. Available data indicate that CD8(+) T lymphocyte responses mediate protection and, recently, several parasite antigens recognised by CD8(+) T cells have been identified. This study set out to determine the nature and extent of polymorphism in two of these antigens, Tp1 and Tp2, which contain defined CD8(+) T-cell epitopes, and to analyse the sequences for evidence of selection.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Methodology/Principal Findings:&lt;/b&gt; Partial sequencing of the Tp1 gene and the full-length Tp2 gene from 82 T. parva isolates revealed extensive polymorphism in both antigens, including the epitope-containing regions. Single nucleotide polymorphisms were detected at 51 positions (similar to 12%) in Tp1 and in 320 positions (similar to 61%) in Tp2. Together with two short indels in Tp1, these resulted in 30 and 42 protein variants of Tp1 and Tp2, respectively. Although evidence of positive selection was found for multiple amino acid residues, there was no preferential involvement of T cell epitope residues. Overall, the extent of diversity was much greater in T. parva isolates originating from buffalo than in isolates known to be transmissible among cattle.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Conclusions/Significance:&lt;/b&gt; The results indicate that T. parva parasites maintained in cattle represent a subset of the overall T. parva population, which has become adapted for tick transmission between cattle. The absence of obvious enrichment for positively selected amino acid residues within defined epitopes indicates either that diversity is not predominantly driven by selection exerted by host T cells, or that such selection is not detectable by the methods employed due to unidentified epitopes elsewhere in the antigens. Further functional studies are required to address this latter point.&lt;/p&gt

Two Theileria parva CD8 T Cell Antigen Genes Are More Variable in Buffalo than Cattle Parasites, but Differ in Pattern of Sequence Diversity

&lt;p&gt;&lt;b&gt;Background:&lt;/b&gt; Theileria parva causes an acute fatal disease in cattle, but infections are asymptomatic in the African buffalo (Syncerus caffer). Cattle can be immunized against the parasite by infection and treatment, but immunity is partially strain specific. Available data indicate that CD8(+) T lymphocyte responses mediate protection and, recently, several parasite antigens recognised by CD8(+) T cells have been identified. This study set out to determine the nature and extent of polymorphism in two of these antigens, Tp1 and Tp2, which contain defined CD8(+) T-cell epitopes, and to analyse the sequences for evidence of selection.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Methodology/Principal Findings:&lt;/b&gt; Partial sequencing of the Tp1 gene and the full-length Tp2 gene from 82 T. parva isolates revealed extensive polymorphism in both antigens, including the epitope-containing regions. Single nucleotide polymorphisms were detected at 51 positions (similar to 12%) in Tp1 and in 320 positions (similar to 61%) in Tp2. Together with two short indels in Tp1, these resulted in 30 and 42 protein variants of Tp1 and Tp2, respectively. Although evidence of positive selection was found for multiple amino acid residues, there was no preferential involvement of T cell epitope residues. Overall, the extent of diversity was much greater in T. parva isolates originating from buffalo than in isolates known to be transmissible among cattle.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Conclusions/Significance:&lt;/b&gt; The results indicate that T. parva parasites maintained in cattle represent a subset of the overall T. parva population, which has become adapted for tick transmission between cattle. The absence of obvious enrichment for positively selected amino acid residues within defined epitopes indicates either that diversity is not predominantly driven by selection exerted by host T cells, or that such selection is not detectable by the methods employed due to unidentified epitopes elsewhere in the antigens. Further functional studies are required to address this latter point.&lt;/p&gt

Bio-nanotechnology application in wastewater treatment

The nanoparticles have received high interest in the field of medicine and water purification, however, the nanomaterials produced by chemical and physical methods are considered hazardous, expensive, and leave behind harmful substances to the environment. This chapter aimed to focus on green-synthesized nanoparticles and their medical applications. Moreover, the chapter highlighted the applicability of the metallic nanoparticles (MNPs) in the inactivation of microbial cells due to their high surface and small particle size. Modifying nanomaterials produced by green-methods is safe, inexpensive, and easy. Therefore, the control and modification of nanoparticles and their properties were also discussed

Fingerprint-based Wi-Fi indoor localization using map and inertial sensors

It is a common understanding that the localization accuracy can be improved by indoor maps and inertial sensors. However, there is a lack of concrete and generic solutions that combine these two features together and practically demonstrate its validity. This article aims to provide such a solution based on the mainstream fingerprint-based indoor localization approach. First, we introduce the theorem called reference points placement, which gives a theoretical guide to place reference points. Second, we design a Wi-Fi signal propagation-based cluster algorithm to reduce the amount of computation. The paper gives a parameter called reliability to overcome the skewing of inertial sensors. Then we also present Kalman filter and Markov chain to predict the system status. The system is able to provide high-accuracy real-time tracking by integrating indoor map and inertial sensors with Wi-Fi signal strength. Finally, the proposed work is evaluated and compared with the previous Wi-Fi indoor localization systems. In addition, the effect of inertial sensors’ reliability is also discussed. Results are drawn from a campus office building which is about 80 m×140 m with 57 access points

Biosynthesis and characterization of a novel, biocompatible medium chain length polyhydroxyalkanoate by Pseudomonas mendocina CH50 using coconut oil as the carbon source

This study validated the utilization of triacylglycerides (TAGs) by Pseudomonas mendocina CH50, a wild type strain, resulting in the production of novel mcl-PHAs with unique physical properties. A PHA yield of 58% dcw was obtained using 20g/L of coconut oil. Chemical and structural characterisation confirmed that the mcl-PHA produced was a terpolymer comprising of three different repeating monomer units, 3-hydroxyoctanoate, 3-hydroxydecanoate and 3-hydroxydodecanoate or P(3HO-3HD-3HDD). Bearing in mind the potential of P(3HO-3HD-3HDD) in biomedical research, especially in neural tissue engineering, in vitro biocompatibility studies were carried out using NG108-15 (neuronal) cells. Cell viability data confirmed that P(3HO-3HD-3HDD) supported the attachment and proliferation of NG108-15 and was therefore, confirmed to be biocompatible in nature and suitable for neural regeneration

No evidence for association between SLC11A1 and visceral leishmaniasis in India.

BACKGROUND: SLC11A1 has pleiotropic effects on macrophage function and remains a strong candidate for infectious disease susceptibility. 5' and/or 3' polymorphisms have been associated with tuberculosis, leprosy, and visceral leishmaniasis (VL). Most studies undertaken to date were under-powered, and none has been replicated within a population. Association with tuberculosis has replicated variably across populations. Here we investigate SLC11A1 and VL in India. METHODS: Nine polymorphisms (rs34448891, rs7573065, rs2276631, rs3731865, rs17221959, rs2279015, rs17235409, rs17235416, rs17229009) that tag linkage disequilibrium blocks across SLC11A1 were genotyped in primary family-based (313 cases; 176 families) and replication (941 cases; 992 controls) samples. Family- and population-based analyses were performed to look for association between SLC11A1 variants and VL. Quantitative RT/PCR was used to compare SLC11A1 expression in mRNA from paired splenic aspirates taken before and after treatment from 24 VL patients carrying different genotypes at the functional promoter GTn polymorphism (rs34448891). RESULTS: No associations were observed between VL and polymorphisms at SLC11A1 that were either robust to correction for multiple testing or replicated across primary and replication samples. No differences in expression of SLC11A1 were observed when comparing pre- and post-treatment samples, or between individuals carrying different genotypes at the GTn repeat. CONCLUSIONS: This is the first well-powered study of SLC11A1 as a candidate for VL, which we conclude does not have a major role in regulating VL susceptibility in India.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are