Dim artificial light at night alters gene expression rhythms and growth in a key seagrass species (Posidonia oceanica)

Artificial light at night (ALAN) is a globally spreading anthropogenic stressor, affecting more than 20% of coastal habitats. The alteration of the natural light/darkness cycle is expected to impact the physiology of organisms by acting on the complex circuits termed as circadian rhythms. Our understanding of the impact of ALAN on marine organisms is lagging behind that of terrestrial ones, and effects on marine primary producers are almost unexplored. Here, we investigated the molecular and physiological response of the Mediterranean seagrass, Posidonia oceanica (L.) Delile, as model to evaluate the effect of ALAN on seagrass populations established in shallow waters, by taking advantage of a decreasing gradient of dim nocturnal light intensity (from < 0.01 to 4 lx) along the NW Mediterranean coastline. We first monitored the fluctuations of putative circadian-clock genes over a period of 24 h along the ALAN gradient. We then investigated whether key physiological processes, known to be synchronized with day length by the circadian rhythm, were also affected by ALAN. ALAN influenced the light signalling at dusk/night in P. oceanica, including that of shorter blue wavelengths, through the ELF3-LUX1-ZTL regulatory network, and suggested that the daily perturbation of internal clock orthologs in seagrass might have caused the recruitment of PoSEND33 and PoPSBS genes to mitigate the repercussions of a nocturnal stress on photosynthesis during the day. A long-lasting impairment of gene fluctuations in sites characterised by ALAN could explain the reduced growth of the seagrass leaves when these were transferred into controlled conditions and without lighting during the night. Our results highlight the potential contribution of ALAN to the global loss of seagrass meadows, posing questions about key interactions with a variety of other human-related stressors in urban areas, in order to develop more efficient strategies to globally preserve these coastal foundation species.

Genome-wide analysis identifies genetic effects on reproductive success and ongoing natural selection at the FADS locus

Identifying genetic determinants of reproductive success may highlight mechanisms underlying fertility and identify alleles under present-day selection. Using data in 785,604 individuals of European ancestry, we identified 43 genomic loci associated with either number of children ever born (NEB) or childlessness. These loci span diverse aspects of reproductive biology, including puberty timing, age at first birth, sex hormone regulation, endometriosis and age at menopause. Missense variants in ARHGAP27 were associated with higher NEB but shorter reproductive lifespan, suggesting a trade-off at this locus between reproductive ageing and intensity. Other genes implicated by coding variants include PIK3IP1, ZFP82 and LRP4, and our results suggest a new role for the melanocortin 1 receptor (MC1R) in reproductive biology. As NEB is one component of evolutionary fitness, our identified associations indicate loci under present-day natural selection. Integration with data from historical selection scans highlighted an allele in the FADS1/2 gene locus that has been under selection for thousands of years and remains so today. Collectively, our findings demonstrate that a broad range of biological mechanisms contribute to reproductive success.

Genetic insights into biological mechanisms governing human ovarian ageing

Reproductive longevity is essential for fertility and influences healthy ageing in women1,2, but insights into its underlying biological mechanisms and treatments to preserve it are limited. Here we identify 290 genetic determinants of ovarian ageing, assessed using normal variation in age at natural menopause (ANM) in about 200,000 women of European ancestry. These common alleles were associated with clinical extremes of ANM; women in the top 1% of genetic susceptibility have an equivalent risk of premature ovarian insufficiency to those carrying monogenic FMR1 premutations3. The identified loci implicate a broad range of DNA damage response (DDR) processes and include loss-of-function variants in key DDR-associated genes. Integration with experimental models demonstrates that these DDR processes act across the life-course to shape the ovarian reserve and its rate of depletion. Furthermore, we demonstrate that experimental manipulation of DDR pathways highlighted by human genetics increases fertility and extends reproductive life in mice. Causal inference analyses using the identified genetic variants indicate that extending reproductive life in women improves bone health and reduces risk of type 2 diabetes, but increases the risk of hormone-sensitive cancers. These findings provide insight into the mechanisms that govern ovarian ageing, when they act, and how they might be targeted by therapeutic approaches to extend fertility and prevent disease.

Genome diversity and instability in human germ cells and preimplantation embryos

Genome diversity is essential for evolution and is of fundamental importance to human health. Generating genome diversity requires phases of DNA damage and repair that can cause genome instability. Humans have a high incidence of de novo congenital disorders compared to other organisms. Recent access to eggs, sperm and preimplantation embryos is revealing unprecedented rates of genome instability that may result in infertility and de novo mutations that cause genomic imbalance in at least 70% of conceptions. The error type and incidence of de novo mutations differ during developmental stages and are influenced by differences in male and female meiosis. In females, DNA repair is a critical factor that determines fertility and reproductive lifespan. In males, aberrant meiotic recombination causes infertility, embryonic failure and pregnancy loss. Evidence suggest germ cells are remarkably diverse in the type of genome instability that they display and the DNA damage responses they deploy. Additionally, the initial embryonic cell cycles are characterized by a high degree of genome instability that cause congenital disorders and may limit the use of CRISPR-Cas9 for heritable genome editing.

Preconception genome medicine: current state and future perspectives to improve infertility diagnosis and reproductive and health outcomes based on individual genomic data

BACKGROUND

Our genetic code is now readable, writable and hackable. The recent escalation of genome-wide sequencing (GS) applications in population diagnostics will not only enable the assessment of risks of transmitting well-defined monogenic disorders at preconceptional stages (i.e. carrier screening), but also facilitate identification of multifactorial genetic predispositions to sub-lethal pathologies, including those affecting reproductive fitness. Through GS, the acquisition and curation of reproductive-related findings will warrant the expansion of genetic assessment to new areas of genomic prediction of reproductive phenotypes, pharmacogenomics and molecular embryology, further boosting our knowledge and therapeutic tools for treating infertility and improving women's health.

OBJECTIVE AND RATIONALE

In this article, we review current knowledge and potential development of preconception genome analysis aimed at detecting reproductive and individual health risks (recessive genetic disease and medically actionable secondary findings) as well as anticipating specific reproductive outcomes, particularly in the context of IVF. The extension of reproductive genetic risk assessment to the general population and IVF couples will lead to the identification of couples who carry recessive mutations, as well as sub-lethal conditions prior to conception. This approach will provide increased reproductive autonomy to couples, particularly in those cases where preimplantation genetic testing is an available option to avoid the transmission of undesirable conditions. In addition, GS on prospective infertility patients will enable genome-wide association studies specific for infertility phenotypes such as predisposition to premature ovarian failure, increased risk of aneuploidies, complete oocyte immaturity or blastocyst development failure, thus empowering the development of true reproductive precision medicine.

SEARCH METHODS

Searches of the literature on PubMed Central included combinations of the following MeSH terms: human, genetics, genomics, variants, male, female, fertility, next generation sequencing, genome exome sequencing, expanded carrier screening, secondary findings, pharmacogenomics, controlled ovarian stimulation, preconception, genetics, genome-wide association studies, GWAS.

OUTCOMES

Through PubMed Central queries, we identified a total of 1409 articles. The full list of articles was assessed for date of publication, limiting the search to studies published within the last 15 years (2004 onwards due to escalating research output of next-generation sequencing studies from that date). The remaining articles' titles were assessed for pertinence to the topic, leaving a total of 644 articles. The use of preconception GS has the potential to identify inheritable genetic conditions concealed in the genome of around 4% of couples looking to conceive. Genomic information during reproductive age will also be useful to anticipate late-onset medically actionable conditions with strong genetic background in around 2-4% of all individuals. Genetic variants correlated with differential response to pharmaceutical treatment in IVF, and clear genotype-phenotype associations are found for aberrant sperm types, oocyte maturation, fertilization or pre- and post-implantation embryonic development. All currently known capabilities of GS at the preconception stage are reviewed along with persisting and forthcoming barriers for the implementation of precise reproductive medicine.

WIDER IMPLICATIONS

The expansion of sequencing analysis to additional monogenic and polygenic traits may enable the development of cost-effective preconception tests capable of identifying underlying genetic causes of infertility, which have been defined as 'unexplained' until now, thus leading to the development of a true personalized genomic medicine framework in reproductive health.

Chromosome errors in human eggs shape natural fertility over reproductive life span

Chromosome errors, or aneuploidy, affect an exceptionally high number of human conceptions, causing pregnancy loss and congenital disorders. Here, we have followed chromosome segregation in human oocytes from females aged 9 to 43 years and report that aneuploidy follows a U-curve. Specific segregation error types show different age dependencies, providing a quantitative explanation for the U-curve. Whole-chromosome nondisjunction events are preferentially associated with increased aneuploidy in young girls, whereas centromeric and more extensive cohesion loss limit fertility as women age. Our findings suggest that chromosomal errors originating in oocytes determine the curve of natural fertility in humans.

Anticarcinogenic activity of blue fluorescent hexagonal boron nitride quantum dots: as an effective enhancer for DNA cleavage activity of anticancer drug doxorubicin

Blue fluorescent hexagonal boron nitride quantum dots (h-BNQDs) of ∼10 nm size as an effective enhancer for DNA cleavage activity of anticancer drug doxorubicin (DOX) were synthesized using simple one-step hydrothermal disintegration of exfoliated hexagonal boron nitride at very low temperature ∼ 120 °C. Boron nitride quantum dots (BNQDs) at a concentration of 25 μg/ml enhanced DNA cleavage activity of DOX up to 70% as checked by converting supercoiled fragment into nicked circular PBR322 DNA. The interaction of BNQDs with DOX is proportional to the concentration of BNQDs, with binding constant K b ∼0.07338 μg/ml. In addition, ab initio theoretical results indicate that DOX is absorbed on BNQDs at the N-terminated edge with binding energy -1.075 eV and prevented the normal replication mechanisms in DNA. BNQDs have been shown to kill the breast cancer cell MCF-7 extensively as compared with the normal human keratinocyte cell HaCaT. The cytotoxicity of BNQDs may be correlated with reduced reactive oxygen species level and increased apoptosis in MCF-7 cells, which may be liable to enhance the anticancerous activity of DOX. The results provide a base to develop BNQD-DOX as a more effective anticancer drug.

Dissipation, intermittency, and singularities in incompressible turbulent flows

We examine the connection between the singularities or quasisingularities in the solutions of the incompressible Navier-Stokes equation (INSE) and the local energy transfer and dissipation, in order to explore in detail how the former contributes to the phenomenon of intermittency. We do so by analyzing the velocity fields (a) measured in the experiments on the turbulent von Kármán swirling flow at high Reynolds numbers and (b) obtained from the direct numerical simulations of the INSE at a moderate resolution. To compute the local interscale energy transfer and viscous dissipation in experimental and supporting numerical data, we use the weak solution formulation generalization of the Kármán-Howarth-Monin equation. In the presence of a singularity in the velocity field, this formulation yields a nonzero dissipation (inertial dissipation) in the limit of an infinite resolution. Moreover, at finite resolutions, it provides an expression for local interscale energy transfers down to the scale where the energy is dissipated by viscosity. In the presence of a quasisingularity that is regularized by viscosity, the formulation provides the contribution to the viscous dissipation due to the presence of the quasisingularity. Therefore, our formulation provides a concrete support to the general multifractal description of the intermittency. We present the maps and statistics of the interscale energy transfer and show that the extreme events of this transfer govern the intermittency corrections and are compatible with a refined similarity hypothesis based on this transfer. We characterize the probability distribution functions of these extreme events via generalized Pareto distribution analysis and find that the widths of the tails are compatible with a similarity of the second kind. Finally, we make a connection between the topological and the statistical properties of the extreme events of the interscale energy transfer field and its multifractal properties.

Using a Novel Microfabricated Model of the Alveolar-Capillary Barrier to Investigate the Effect of Matrix Structure on Atelectrauma

The alveolar-capillary barrier is composed of epithelial and endothelial cells interacting across a fibrous extracelluar matrix (ECM). Although remodeling of the ECM occurs during several lung disorders, it is not known how fiber structure and mechanics influences cell injury during cyclic airway reopening as occurs during mechanical ventilation (atelectrauma). We have developed a novel in vitro platform that mimics the micro/nano-scale architecture of the alveolar microenvironment and have used this system to investigate how ECM microstructural properties influence epithelial cell injury during airway reopening. In addition to epithelial-endothelial interactions, our platform accounts for the fibrous topography of the basal membrane and allows for easy modulation of fiber size/diameter, density and stiffness. Results indicate that fiber stiffness and topography significantly influence epithelial/endothelial barrier function where increased fiber stiffness/density resulted in altered cytoskeletal structure, increased tight junction (TJ) formation and reduced barrier permeability. However, cells on rigid/dense fibers were also more susceptible to injury during airway reopening. These results indicate that changes in the mechanics and architecture of the lung microenvironment can significantly alter cell function and injury and demonstrate the importance of implementing in vitro models that more closely resemble the natural conditions of the lung microenvironment.

Ruptured submitral aneurysm

Submitral aneurysm is a rare entity, with around few hundred cases reported till date. Presentation can be varied. We describe here a case of submitral aneurysm in a young male with rupture into the left atrium cavity.

Relationship between carotid intima thickness and silent cerebral infarction in patients with type 2 diabetic nephropathy

AIM

To examine the relationship between carotid intima media thickness (CIMT) and silent cerebral infarction (SCI) in order to determine whether CIMT is a predictor of SCI in patients of type 2 diabetic nephropathy.

METHODS

A total of 80 patients of type 2 diabetic nephropathy were selected on the basis of fasting and 2-hour post-prandial blood sugar, 24 hrs albumin estimation in urine, urea and creatinine in the serum. The selected candidates underwent MRI brain and carotid B mode ultrasonography to find out the event of SCI and to evaluate the CIMT respectively.

RESULTS

The SCI was found in 30 (37.5%) patients with type 2 diabetic nephropathy. The mean age, BMI, blood pressure (BP), macroalbuminuria, S. lipids, low GFR, duration of diabetes and CIMT were significantly higher in the subject with SCI than in those without it. Multiple logistic analyses indicated that age, BP, and CIMT were found to be significant and independent risk factors of SCI in type 2 diabetic nephropathy subjects.

CONCLUSION

CIMT is a surrogate and reliable predictor of higher risk of SCI among type 2 diabetic nephropathy patients.

Predictors of diabetic retinopathy in patients with type 2 diabetes who have normoalbuminuria

Background:

Microalbuminuria is an independent predictor of retinopathy, so absence of microalbuminuria may tend clinician not to screen for diabetic retinopathy (DR).

Aim:

The aim of our study was to estimate prevalence of DR in patients with type 2 diabetes who have normoalbuminuria, and to study predictors for DR, which can identify these high-risk individuals.

Subjects and Methods:

In a prospective cross-sectional study that included patients with type 2 DM and normoalbuminuria. Diagnosis of DR was made by a trained ophthalmologist based on the presence of clinical features in the fundus of both eyes following the International Clinical DR guidelines. The statistical analyses were performed using Statistical Package for the Social Sciences 15.0 version software (Chicago, IL, USA). The continuous variables expressed as means (SD and Student's t-test or Mann–Whitney test were used, as appropriate, to determine differences in them. Categorical variables were presented as percentage. The Pearson's Chi-square test or Fisher's exact test, as appropriate, was used to determine the differences in them.

Results:

A total of 226 patients with type 2 DM and normoalbuminuria were enrolled in the study that included 110 males (48.6%), and 116 females (51.4%) Mean (SD) duration of diabetes was 8.2 (5.6) years. DR of any grade was present in 49/226 (22%) patients. Of the patients with DR of any grade, 31/49 (63%) had mild non-proliferative diabetic retinopathy (NPDR) 10/49 (22%) had moderate to severe NPDR and 8/49 (15%) had PDR. Duration of diabetes (OR 1.01, 95% CI, 0.86-2.2, P = 0.04), higher systolic blood pressure (OR 2.2, 95% CI, 1.6-4.5, P = 0.01), low hemoglobin (OR 1.4, 95% CI, 0.45-2.9, P = 0.01), and a higher tertile of urinary albumin excretion rate (OR 4.12, 95% CI, 1.92-7.57, P = 0.001) had independently significant association with DR.

Conclusion:

The risk of DR exists in patients with type 2 diabetes even in normoalbuminuric individuals. Close monitoring is particularly needed if patients have longer duration of diabetes, hypertension, anemia, or high normal albuminuria.

Drought yield index to select high yielding rice lines under different drought stress severities

BACKGROUND

Drought is the most severe abiotic stress reducing rice yield in rainfed drought prone ecosystems. Variation in intensity and severity of drought from season to season and place to place requires cultivation of rice varieties with different level of drought tolerance in different areas. Multi environment evaluation of breeding lines helps breeder to identify appropriate genotypes for areas prone to similar level of drought stress. From a set of 129 advanced rice (Oryza sativa L.) breeding lines evaluated under rainfed drought-prone situations at three locations in eastern India from 2005 to 2007, a subset of 39 genotypes that were tested for two or more years was selected to develop a drought yield index (DYI) and mean yield index (MYI) based on yield under irrigated, moderate and severe reproductive-stage drought stress to help breeders select appropriate genotypes for different environments.

RESULTS

ARB 8 and IR55419-04 recorded the highest drought yield index (DYI) and are identified as the best drought-tolerant lines. The proposed DYI provides a more effective assessment as it is calculated after accounting for a significant genotype x stress-level interaction across environments. For rainfed areas with variable frequency of drought occurrence, Mean yield index (MYI) along with deviation in performance of genotypes from currently cultivated popular varieties in all situations helps to select genotypes with a superior performance across irrigated, moderate and severe reproductive-stage drought situations. IR74371-70-1-1 and DGI 75 are the two genotypes identified to have shown a superior performance over IR64 and MTU1010 under all situations.

CONCLUSION

For highly drought-prone areas, a combination of DYI with deviation in performance of genotypes under irrigated situations can enable breeders to select genotypes with no reduction in yield under favorable environments compared with currently cultivated varieties. For rainfed areas with variable frequency of drought stress, use of MYI together with deviation in performance of genotypes under different situations as compared to presently cultivated varieties will help breeders to select genotypes with superior performance under all situations.

Studies on optical limiting characteristics of silicon nanoparticles synthesized by laser ablation

We present synthesis of silicon nanoparticles dispersed in toluene by laser ablation and studies on their optical limiting properties with nanosecond laser pulses at 532 nm. Silicon nanoparticles in toluene show better optical limiting compared to standard optical limiter fullerene C60 in toluene. Optical limiting threshold of silicon nanoparticles is about three times less than that of C60. Detailed studies using Z-scan experiments, angle dependent scattering, intensity dependent transmission and temporal profile measurements indicate that apart from non-linear scattering, nonlinear absorption and nonlinear refraction also contribute to the optical limiting behavior of silicon nanoparticles.

Do insulin-like growth factor associated proteins qualify as a tumor marker? Results of a prospective study in 163 cancer patients

OBJECTIVE

Insulin-like growth factor (IGF)-1, -2 and Insulin like growth factor binding proteins (IGFBP) are involved in the proliferation and differentiation of cells. It has never been evaluated, if the IGF-system can serve as a tumor marker in neoplasms.

METHODS

In our prospective study 163 patients with colorectal cancer (22), prostate cancer (21), head and neck tumors (17), lymphomas (20), lung cancer (34) and other entities (49) were analysed for their IGF and IGFBP serum levels at the beginning and the end of radiotherapy and compared to 13 healthy people. Subgroups of patients with local tumor disease versus metastatic disease, primary and recurrent therapy and curative versus palliative therapy were compared.

RESULTS

The serum levels of IGF-2 were significantly elevated in patients with prostate and colorectal cancer. However, sensitivity and specificity were only 70%. IGFBP-2 serum levels were elevated in patients with head and neck tumors. Again sensitivity and specificity were only 73%. A difference between local disease and metastatic disease could not be found. A difference between IGF serum levels before and after radiotherapy could not be detected.

CONCLUSION

The IGF-system cannot serve as a new tumor marker. The detected differences are very small, sensitivity and specificity are too low. IGF measurement is not useful for the evaluation of the success of radiotherapy in malignancies.

Potential for engineering horticultural crops with high antioxidant capacity

Abstract

Cellular oxidation index has emerged as an important determinant in defining the fate of a living cell and its susceptibility to disease. Oxidative stress targets include oxidation of DNA, protein and lipids; causing cellular oncogenesis, chronic diseases and premature senescence. The possibility that dietary intervention via nutrition-enriched food may significantly decrease incidence of diet-related diseases has catalysed scientific efforts to understand this relationship, which is fundamental to developing future strategies for stemming disease. Multiple and synergistic interactions among nutrients influence antiproliferative activity of a fruit compared with an isolated antioxidant. Nutritional molecules including vitamins (B, C, E and β-carotene), folates, lycopene, flavonoids, isothyocyanates, glucosinolates, polyphenols, glutathione and minerals contribute to the antioxidative capacity of vegetables, fruits, nuts and various herbs. The true potential of a supplemental antioxidant or crop nutrients in human health benefits is in their accessibility, bioavailability and biological potency. Studies on the absorption, metabolism and in vivo potency of phytonutrients have lagged behind and are only now beginning to provide some results. Also, it is important to bear in mind that the levels of phytonutrients present in horticultural crops are low and significantly influenced by genotype/cultivar, growth condition and developmental stage. In this regard, genetic engineering has become a refined tool to increase the antioxidant and nutrient capacity of economically important crops including fruits and vegetables to the levels favourable not only for a highly nutritional diet but also to enable in-depth studies on the relationships between diet, genetics and metabolism. Together with modern biotechnology, deciphering transcriptome-proteome-metabolome of the new transgenics should provide new knowledge to ease the concerns of the society and open the market for genetically engineered horticulture crops, as is seen by higher sales of Hawaii-grown transgenic papaya in the USA. Also, this knowledge will help us in developing precise strategies for redesigning metabolic pathways so that desired levels of a particular phytonutrient (antioxidant) in crops are achieved.

Granulomatous hepatitis following open heart surgery with cardiopulmonary bypass

BACKGROUND

Cardiopulmonary bypass (CPB) initiates an inflammatory cascade, predisposing the patient to a number of infections. The stress of surgery and anaesthesia further expose the patient to a variety of non-infectious complications. We report a group of patients who developed granulomatous disease after open heart surgery.

METHODS

We retrospectively analysed a subset of patients who developed a syndrome of fever, jaundice and hepatomegaly after open heart surgery. We recruited age- and sex-matched controls who underwent open heart surgery during the same period (July 2002-July 2004). Details of demographic profiles, diagnostic evaluation and drug treatment were noted and compared between the two groups using the SPSS software.

RESULTS

Five patients were identified to have the specific syndrome of high grade intermittent fever with jaundice and hepatomegaly with investigations revealing an intrahepatic cholestasis. A detailed evaluation revealed granulomas in tissue specimens of the bone marrow and/or liver in these patients. An extensive evaluation for an alternative aetiological agent was non-contributory.

CONCLUSION

We found granulomatous hepatitis in 5 patients following open heart surgery and they were given conventional antituberculous therapy to which they responded. It is possible that in these patients, tuberculosis was re-activated from a dormant focus due to a period of transient immunodeficiency caused by an extracorporeal circulation.

Orchestration of chromatin-based processes: mind the TRRAP

Chromatin modifications at core histones including acetylation, methylation, phosphorylation and ubiquitination play an important role in diverse biological processes. Acetylation of specific lysine residues within the N terminus tails of core histones is arguably the most studied histone modification; however, its precise roles in different cellular processes and how it is disrupted in human diseases remain poorly understood. In the last decade, a number of histone acetyltransferases (HATs) enzymes responsible for histone acetylation, has been identified and functional studies have begun to unravel their biological functions. The activity of many HATs is dependent on HAT complexes, the multiprotein assemblies that contain one HAT catalytic subunit, adapter proteins, several other molecules of unknown function and a large protein called TRansformation/tRanscription domain-Associated Protein (TRRAP). As a common component of many HAT complexes, TRRAP appears to be responsible for the recruitment of these complexes to chromatin during transcription, replication and DNA repair. Recent studies have shed new light on the role of TRRAP in HAT complexes as well as mechanisms by which it mediates diverse cellular processes. Thus, TRRAP appears to be responsible for a concerted and context-dependent recruitment of HATs and coordination of distinct chromatin-based processes, suggesting that its deregulation may contribute to diseases. In this review, we summarize recent developments in our understanding of the function of TRRAP and TRRAP-containing HAT complexes in normal cellular processes and speculate on the mechanism underlying abnormal events that may lead to human diseases such as cancer.

Computer visualization techniques (CVTs) foster evidence-based target delineation

Computer visualization techniques (CVTs) are an emerging technology that can organize all cancer specialists. This article describes CVTs' ability to maximize the currently untapped advantages of intensity modulated radiotherapy (IMRT). The visual speed and dynamic strategies inherent in CVTs improves IMRT by distilling vast amounts of anatomic, multimodal imaging, textual/meaning, and surgical/outcome data into a large, rigorous, standardized evidence base of storable target delineation plans. This ability to standardize strategies will allow the collection of meaningful evidence based outcome data.

The significance of post-traumatic amnesia as a risk factor in the development of olfactory dysfunction following head injury

OBJECTIVE

To test the following hypothesis in the assessment of head injury

PATIENTS

only patients with 5 min or more of post-traumatic amnesia (PTA) are at risk of acute olfactory dysfunction (OD).

METHODS

This was a retrospective comparative study of olfactory status in head injury patients seen at a head injury clinic at Glasgow Royal Infirmary from 1985 to 2003. Of 828 clinic attenders, 101 had acute OD. These subjects were compared with a randomly selected control group of 102 patients with head injury but normal olfactory function. The main outcome measure was a significant likelihood of patients with PTA lasting for 5 or more minutes having acute OD compared with those with PTA of less than 5 min.

RESULTS

The likelihood of patients with a PTA of 5 min or more having acute OD compared to those with PTA of less than 5 min is clinically significant with an odds ratio of 9.6 (p<0.01).

CONCLUSION

Examination of patients with 5 min or more of PTA should include a simple test of sense of smell. Patients with impaired smell sensation should be aware of their condition prior to discharge from hospital. In addition, the need for a CT brain scan and appropriate follow up should be considered.

A missing denture's misadventure!

We report a late onset, benign, tracheoesophageal fistula in a 51-year-old man, due to an accidentally swallowed denture. In view of the extensive peri-esophageal sepsis and fibrosis, he was managed by a subtotal esophagectomy and a cervical esophagogastric anastomosis. The tracheal defect was closed with the help of an intercostal muscle flap. This report also highlights the difficulty in identifying swallowed prosthetic dental material radiologically, when no metallic component is present. This fact was also responsible for the delay in diagnosis, eventually leading to the rare complication of a tracheoesophageal fistula.

Systemic absorption of FD&C blue dye associated with patient mortality

The addition of FD&C blue dye to enteral feeds is a common practice in hospitals to detect aspiration. However, the degree of systemic absorption and safety of this dye in critically ill patients has not been studied. A patient with sepsis who died after systemic absorption of FD&C blue dye No1 is described.

Synthesis and evaluation of novel bioconjugates as antiviral agents

Novel lipid (mannito-stearate) antiviral nucleoside and oligonucleotide conjugates were prepared with improved lipophilic and membrane associating properties of drugs. Potential advantages of these liponucleotide prodrugs are lower toxicity, increased cellular uptake, nuclease resistivity and antiviral activity. Oligonucleotide conjugate complementary to a unique segment of viral genome may selectively disrupt the processes dependent on the segment by hybridisation.

Amelioration of B16F10 melanoma cells induced oxidative stress in DBA/2 mice by pentoxifylline

The constantly produced small amounts of reactive oxygen species (ROS) are reduced by anti-oxidant enzymes and cellular scavengers. The oxidative stress developed by defect in ROS clearance can result in cell injury and may lead to carcinogenesis. Pentoxifylline is a methylxanthine derivative with rheologic and membrane modifier property. We have examined whether Pentoxifylline (PTX) ameliorates oxidative stress produced in subcutaneously injected mice with B16F10 melanoma cells. Treatment of mice with PTX significantly reduced oxidative stress and attenuated the altered changes of reduced glutathione and lipid peroxides. Our findings provide an experimental basis for using PTX to attenuate oxidative stress induced by B16F10 melanoma cells in liver and lung of DBA/2 mice.

Lead poisoning in Indian silver refiners

The refining of silver from old silver ornaments, articles and jeweller's waste by smelting these with lead scraps for the fabrication of new jewellery is an important small scale industry in India. The present survey and clinical investigations have shown that 31 out of 50 silver refiners with a mean blood lead level of 32.84+/-1.78 microg/dl (range 20.3-64.9), decrease in blood delta-aminolevulinic acid dehydratase (ALAD) activity and thiamine (as pyruvate) level and an enhanced urinary excretion of ALA as compared to control, were suffering from lead poisoning. Most of these workers have shown anaemia, abdominal colic, blue lining of gum and muscular wasting indicative of lead toxicity. Twenty-four workers with relatively high blood lead levels were equally divided into two groups and given either vitamin B1 (75 mg, once a day) or vitamin C (250 mg. twice a day) for 1 month. The treatment with both the vitamins significantly lowered the blood lead levels and reduced blood thiamine and copper deficiency. In addition, vitamin C was also effective in reversing the inhibition of blood ALAD activity while the effect of vitamin B1 on its activity was marginal. The daily intake of vitamin B1 and vitamin C may prevent the accumulation of lead and reduce its toxic effects particularly in those regularly exposed to lead.

Fungal morphology and fragmentation behavior in a fed-batch Aspergillus oryzae fermentation at the production scale

It is well known that high-viscosity fermentation broth can lead to mixing and oxygen mass transfer limitations. The seemingly obvious solution for this problem is to increase agitation intensity. In some processes, this has been shown to damage mycelia, affect morphology, and decrease product expression. However, in other processes increased agitation shows no effect on productivity. While a number of studies discuss morphology and fragmentation at the laboratory and pilot scale, there are relatively few publications available for production-scale fungal fermentations. The goal of this study was to assess morphology and fragmentation behavior in large-scale, fed-batch, fungal fermentations used for the production of protein. To accomplish this, a recombinant strain of Aspergillus oryzae was grown in 80 m(3) fermentors at two different gassed, impeller power-levels (one 50% greater than the other). Impeller power is reported as energy dissipation/circulation function (EDCF) and was found to have average values of 29.3 +/- 1.0 and 22.0 +/- 0.3 kW m(-3) s(-1) at high and low power levels, respectively. In all batches, biomass concentration profiles were similar and specific growth rate was < 0.03 h(-1). Morphological data show hyphal fragmentation occurred by both shaving-off of external clump hyphae and breakage of free hyphae. The fragmentation rate constant (k(frag)), determined using a first-order model, was 5.90 and 5.80 h(-1) for high and low power batches, respectively. At the end of each batch, clumps accounted for only 25% of fungal biomass, most of which existed as small, sparsely branched, free hyphal elements. In all batches, fragmentation was found to dominate fungal growth and branching. We speculate that this behavior was due to slow growth of the culture during this fed-batch process.

Repair of isolated multiple muscular ventricular septal defects: the septal obliteration technique

BACKGROUND

Isolated multiple ventricular septal defects (mVSDs) remain a surgical challenge. The dilemma of whether to perform a complete repair ultimately rests with the surgeon, who must decide if all significant septal defects can be located. Avoidance of a pulmonary arterial band (as part of a two-stage repair) will negate the need for future pulmonary arterial reconstruction and will reduce the incidence of late right ventricular diastolic dysfunction.

METHODS

We performed a retrospective analysis of hospital and echocardiographic data of eight children who underwent a septal obliteration technique (SOT) as part of their correction of mVSDs (with and without coarctation of the aorta).

RESULTS

Eight children with a mean age of 10.5 months (range 1.5 to 36 months), and weight of 6.2 kg (range 2.1 to 13.5 kg), respectively, underwent correction of mVSDs. All had a single, large, perimembranous defect, additional VSDs within the muscular trabecular septum (juxtaposed to the moderator band), and apical mVSDs. All VSDs were repaired via the right atrium, with avoidance of either a right or left ventriculotomy. The posterior and apical defects were excluded from the right ventricular cavity with a pericardial patch (SOT). The follow-up period remains limited to a mean of 20.9 months (8 to 39 months). Two children repaired with SOT had previous pulmonary artery bands (neonatal coarctation repair). All children were successfully discharged home with a mean postoperative Qp:Qs of 1.09:1. One pacemaker was required, but this child has since reverted back to normal sinus rythm.

CONCLUSIONS

Our initial experience using the SOT in the treatment of apical VSDs as a component of isolated mVSDs has been rewarding. All children are currently alive, in normal sinus rhythm, and have no residual significant left-to-right shunts.