G2S: a web-service for annotating genomic variants on 3D protein structures.

Motivation: Accurately mapping and annotating genomic locations on 3D protein structures is a key step in structure-based analysis of genomic variants detected by recent large-scale sequencing efforts. There are several mapping resources currently available, but none of them provides a web API (Application Programming Interface) that supports programmatic access. Results: We present G2S, a real-time web API that provides automated mapping of genomic variants on 3D protein structures. G2S can align genomic locations of variants, protein locations, or protein sequences to protein structures and retrieve the mapped residues from structures. G2S API uses REST-inspired design and it can be used by various clients such as web browsers, command terminals, programming languages and other bioinformatics tools for bringing 3D structures into genomic variant analysis. Availability and implementation: The webserver and source codes are freely available at https://g2s.genomenexus.org. Contact: g2s@genomenexus.org. Supplementary information: Supplementary data are available at Bioinformatics online.

Utilizing dual energy CT to improve CT diagnosis of posterior fossa ischemia.

BACKGROUND AND PURPOSE: Evaluation of posterior fossa ischemia on conventional CT is limited. The goal of our study was to determine if virtual monochromatic CT increases the diagnostic accuracy for the detection of posterior infarcts relative to standard CT while using diffusion-weighted MRI as a reference standard. METHODS: Thirty consecutive subjects who meet the following inclusion criteria were retrospectively enrolled: (1) symptoms of posterior fossa stroke (e.g. vertigo, fainting, and dizziness), (2) unenhanced dual-energy CT of the head performed upon admission to the emergency department, and (3) MRI of the brain within 7 days following the CT. Eight of the 30 subjects were determined to have MRI diffusion-weighted imaging findings consistent with acute posterior fossa ischemia. Monochromatic energy reconstructions at 60, 80, 100, 120keV and the clinical CT were interpreted independently by two fellowship-trained neuroradiologists, who assessed the images for posterior fossa infarcts and for imaging quality. RESULTS: Reconstructions obtained at 80keV provided the best artifact reduction and overall maximization of image quality and were statistically significantly better than standard head CT (P<0.001). Sensitivity, specificity, positive predictive value, and negative predictive value were at least not less than standard CT, and there was a trend toward better values at 100keV (P=0.096). CONCLUSION: Monoenergetic 80 or 100keV reconstructions may improve the detection of posterior fossa ischemia compared to conventional CT. However, if clinical suspicion for posterior fossa ischemia warrants, a brain MRI with diffusion-weighted imaging should still be obtained, even in the presence of a negative dual energy CT of the brain.

Monitoring and treatment results of 88 HBsAg-positive pregnant women.

Approximately 5% of all women in the world are HBsAg-positive. Chronic hepatitis B is a problem in women of reproductive age. This paper assessed 88 HBsAg-positive pregnant women, of whom 11 began treatment during pregnancy and five became pregnant while receiving treatment. The files of HBsAg-positive pregnant women were reviewed between January 2010 and December 2013-retrospectively. From these 88 pregnant women, 72 did not receive any treatment during their pregnancy, 11 began treatment during their pregnancy, and five became pregnant while receiving treatment. Nine of these 11 pregnant women were given tenofovir disoproxil fumarate and two of them lamivudine. Ten babies of the 11 mothers that began treatment during their pregnancy were healthy, but one was lost due to preterm birth. Of the five patients who became pregnant while receiving treatment, the treatments of four women were discontinued and they were monitored during their pregnancies because mild-moderate (less than stage 3) fibrosis was found in their liver biopsy results. It is important to screen all pregnant women for hepatitis B and to assess those found HBsAg-positive. It is possible to protect both the mother and baby using appropriate approaches.

Serum annexin A2 levels in acute brucellosis and brucellar spondylodiscitis.

Brucellosis is a chronic granulomatous infection and may present with various clinical manifestations. Brucellar spondylodiscitis symptoms are initially subtle and nonspecific. Annexin A2 (ANXA2) is involved in various biological functions, including osteoclast formation, bone resorption, and cell growth regulation. In this study, we aimed to determine the clinical significance of serum ANXA2 levels in acute brucellosis and brucellar spondylodiscitis. This prospective study included 96 acute brucellosis patients and 51 healthy controls. Acute brucellosis was diagnosed by a 1/160 or higher titer in a standard tube agglutination (STA) test or a four-fold increase in titers between two STA tests performed two weeks apart in the presence of clinical symptoms within the last eight weeks and/or growth of Brucella spp. in appropriately prepared culture media. ANXA2 levels were determined with an enzyme-linked immunosorbent assay (ELISA). Forty (41.7 %) of 96 acute brucellosis patients were male and 56 (58.3 %) were female. Serum ANXA2 levels were elevated in patients compared to healthy controls (p = 0.001). Eighteen of 96 (18.7 %) acute brucellosis patients had brucellar spondylodiscitis. The serum ANXA2 levels of patients with brucellar spondylodiscitis were higher than those of patients with acute disease without brucellar spondylodiscitis (p = 0.001). ANXA2, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) values were elevated in the brucellar spondylodiscitis group compared to patients without brucellar spondylodiscitis. Serum ANXA2 measurement together with ESR and CRP is thought to be indicative in the diagnosis of brucellar spondylodiscitis, a common complication of brucellosis.

Intravoxel incoherent motion perfusion imaging in acute stroke: initial clinical experience.

INTRODUCTION: Intravoxel incoherent motion (IVIM) imaging is an MRI perfusion technique that uses a diffusion-weighted sequence with multiple b values and a bi-compartmental signal model to measure the so-called pseudo-diffusion of blood caused by its passage through the microvascular network. The goal of the current study was to assess the feasibility of IVIM perfusion fraction imaging in patients with acute stroke. METHODS: Images were collected in 17 patients with acute stroke. Exclusion criteria were onset of symptoms to imaging >5 days, hemorrhagic transformation, infratentorial lesions, small lesions <0.5 cm in minimal diameter and hemodynamic instability. IVIM imaging was performed at 3 T, using a standard spin-echo Stejskal-Tanner pulsed gradients diffusion-weighted sequence, using 16 b values from 0 to 900 s/mm(2). Image quality was assessed by two radiologists, and quantitative analysis was performed in regions of interest placed in the stroke area, defined by thresholding the apparent diffusion coefficient maps, as well as in the contralateral region. RESULTS: IVIM perfusion fraction maps showed an area of decreased perfusion fraction f in the region of decreased apparent diffusion coefficient. Quantitative analysis showed a statistically significant decrease in both IVIM perfusion fraction f (0.026 ± 0.019 vs. 0.056 ± 0.025, p=2.2 · 10(-6)) and diffusion coefficient D compared with the contralateral side (3.9 ± 0.79 · 10(-4) vs. 7.5 ± 0.86 · 10(-4) mm(2)/s, p=1.3 · 10(-20)). CONCLUSION: IVIM perfusion fraction imaging is feasible in acute stroke. IVIM perfusion fraction is significantly reduced in the visible infarct. Further studies should evaluate the potential for IVIM to predict clinical outcome and treatment response.

Lipoid Pneumonia Secondary to Diesel Aspiration: An Occupational Hazard.

Lipoid pneumonia is defined as a type of pneumonia that occurs as a result of inhalation of either endogenous or exogenous lipid-containing products in the lungs. We present the case of a 55-year-old male patient who presented with chief complaints of cough with blood-tinged sputum, right-sided chest pain, dyspnea, and fever for two days. The patient gave a history of working as a mechanic in an automobile garage and reported an episode of accidental aspiration of diesel during diesel siphoning at the workplace. A chest X-ray and computed tomography (CT) scan of the chest were done, which revealed right-sided lower lobe consolidation. The patient was admitted and started on intravenous antibiotics, corticosteroids, and inhaled bronchodilators, along with oxygen support. A bronchoscopy was done, which revealed the presence of thick mucoid secretions in the right lower lobe bronchus. The patient was discharged after 10 days with stable vitals and was advised to have regular follow-ups to monitor for any long-term pulmonary complications.

The Role of Continuous Positive Airway Pressure (CPAP) Therapy in Obstructive Sleep Apnea With Metabolic Syndrome: Does It Affect the Outcomes?

Background Of all fatalities occurring globally each year caused by noncommunicable diseases, obstructive sleep apnea (OSA) and obesity are associated with an increased risk of sudden death and cardiovascular mortality. Metabolic syndrome and its comorbidities are linked to OSA. The three essential elements of the metabolic syndrome are improper lipid metabolism, hypertension, and insulin resistance. The effect of continuous positive airway pressure (CPAP) on metabolic syndrome elements and related symptoms and whether CPAP therapy helps reverse the syndrome was studied. Methods The present study is prospective pre-post research conducted at a tertiary care center in Nagpur, Hingna, India. The cases included were of moderate to severe or worse OSA, older than 18 years, willing for CPAP therapy with no previous or current CPAP therapy. They had a history of excessive drowsiness during the day. The cases excluded from the study were those with an active, persistent breathing ailment requiring treatment, intervention, or diagnosis of dyslipidemia, diabetes mellitus, or hypertension, past or present, or evidence of damage to the vital end organs. Components of the metabolic syndrome were assessed at the beginning and end of three months of CPAP therapy. Findings Eighty-five cases were enrolled in the study, of which 79 completed it. The majority of cases were male, comprising 48 individuals, accounting for 60.8% of the total cohort. Additionally, 54 cases, representing 68.4% of the group, had hypertension. The average age of the participants was 53.95 years ± 6.84 years. The BMI mean was 30.4 kg/m2 ± 4.642, with a waist-hip ratio of 0.964 ± 0.056 and a neck circumference of 40.66 cm ± 3.37. The study population scored 12.53 ± 2,616 on the Epworth Sleepiness Scale. The study population's apnea-hypopnea index/respiratory disturbance index ratio was 16.118 ± 4.868, a moderate risk score. After three months of CPAP therapy, there was a significant improvement in glycated hemoglobin (HbA1c), tetraiodothyronine (T4), high-density lipoprotein (HDL), and oxygen desaturation, and they were also statistically significant. In the study group, there was a decrease in systolic and diastolic blood pressure of 2.21 mm Hg and 0.26 mm Hg, respectively. Other indicators, including HbA1c, fasting and post-meal blood sugar, triglycerides, and HDL cholesterol, were significantly lower. We observed in the less than 50-year-old age group better improvement in systolic blood pressure of 0.49 mm Hg, diastolic blood pressure improvement of 0.32 mm Hg, and fasting blood sugar improvement of 14.59 mg/dl, and in the age group of more than 50, better improvements in post-meal blood sugar of 9.7 mg/dl, along with a statistically significant change in triglyceride with an improvement of 16.26 mg/dl, P value less than 0.05. Interpretation After three months of CPAP therapy, there was a significant improvement in HbA1c, T4, HDL, and oxygen desaturation, and they were also statistically significant. Fourteen (17.72%) cases of post-CPAP therapy no longer met the requirements for the syndrome. There was an improvement in the blood pressure's diastolic and systolic values, fasting and post-prandial sugar levels, HbA1C, and triglyceride levels. Patients over 50 years old showed better improvement in post-meal and triglyceride levels. Females improved blood pressure and triglycerides, whereas males responded better to blood sugar levels.

Variation in social media sensitivity across people and contexts.

Social media impacts people's wellbeing in different ways, but relatively little is known about why this is the case. Here we introduce the construct of "social media sensitivity" to understand how social media and wellbeing associations differ across people and the contexts in which these platforms are used. In a month-long large-scale intensive longitudinal study (total n = 1632; total number of observations = 120,599), we examined for whom and under which circumstances social media was associated with positive and negative changes in social and affective wellbeing. Applying a combination of frequentist and Bayesian multilevel models, we found a small negative average association between social media use AND subsequent wellbeing, but the associations were heterogenous across people. People with psychologically vulnerable dispositions (e.g., those who were depressed, lonely, not satisfied with life) tended to experience heightened negative social media sensitivity in comparison to people who were not psychologically vulnerable. People also experienced heightened negative social media sensitivity when in certain types of places (e.g., in social places, in nature) and while around certain types of people (e.g., around family members, close ties), as compared to using social media in other contexts. Our results suggest that an understanding of the effects of social media on wellbeing should account for the psychological dispositions of social media users, and the physical and social contexts surrounding their use. We discuss theoretical and practical implications of social media sensitivity for scholars, policymakers, and those in the technology industry.

Situating smartphones in daily life: Big Five traits and contexts associated with young adults' smartphone use.

We examine individual differences in smartphone behavior to understand the independent effects of Big Five traits and four different contextual factors (places, people, co-occurring activities, and psychological situations) on the frequency and duration of smartphone use in daily life. Using survey, experience sampling, and mobile sensing data collected over the span of 2 weeks from two samples of college students (Sample 1, N = 634; Sample 2, N = 211), we conducted a series of multilevel Bayesian gamma hurdle and negative binomial hurdle models to explain smartphone use (vs. nonuse) and the degree of use. Our pooled findings suggest that extraversion was associated with more frequent use, while conscientiousness was associated with smartphone nonuse and shorter durations of use. In terms of context, our findings show that smartphones were used more frequently when people were out and about in public places (e.g., cafes, stores) and less frequently in particularly social places (e.g., bars, friends' houses). Smartphones were also used more frequently with weak ties (e.g., classmates, coworkers) and less frequently with close ties (e.g., roommates, family, significant others). Smartphones were also used less and for shorter durations when people were engaged in certain activities (e.g., studying, commuting, chores, exercising), and when in situations perceived to be romantic or involving work. We discuss the findings with regard to past work on smartphone use and describe the next steps for research on smartphone behavior. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Chronic Tubercular Mediastinitis: A Rare Case Presentation With Subcutaneous Emphysema.

Tuberculosis, histoplasmosis, various fungal infections, malignancy, and sarcoidosis are the most common causes of chronic or slowly progressing mediastinitis. Chronic mediastinitis of tubercular origin with subcutaneous emphysema is exceptionally uncommon, and the majority of cases are caused by trauma. Here we report the case of a 35-year-old chronic alcoholic male who presented to the Outpatient Department (OPD) with complaints of cough, chest pain, loss of weight, and intermittent low-grade fever for three months with no significant past medical history or family history for any respiratory diseases. He was admitted and all routine investigations were performed, which were normal including his chest X-ray, except erythrocyte sedimentation rate (ESR) which was raised. The patient's high-resolution Computed Tomography (HRCT) of the thorax was done which showed multiple pleural-based nodular lesions with few showing central cavitary nodules along with ground glass appearance. It also showed two fistulous tracks of 3.4-millimeter diameter, arising from the trachea at the T1 - T2 vertebral level and at the carina which led to the presence of air in the subcutaneous plane extending from the neck up to visualized abdomen suggestive of chronic mediastinitis with tracheal fistula, along with subcutaneous emphysema. This fistula was confirmed by video bronchoscopy as well as three-dimensional (3D) virtual bronchoscopy. A biopsy was taken, which was positive for acid-fast bacilli (AFB) stain, polymerase chain reaction (PCR) for tuberculosis, and positive tuberculin skin test. The patient was started on anti-tubercular treatment and on a follow-up visit upon completion of the intensive phase, his HRCT and video bronchoscopy showed fibrosing scarring with fistula closure.

A case of tubercular empyema with pyopneumothorax.

Pyopneumothorax is a common complication associated with tuberculosis, especially in patients with lung parenchymal cavitatory lesions. In this publication, we highlight the case of a 43-year-old female patient who presented with chief complaints of dry cough, left-sided chest pain, and dyspnea on exertion. An X-ray of the chest posteroanterior (PA) view, revealed a left-sided moderate pleural effusion with pneumothorax. Immediate intercostal chest drain (ICD) insertion was done and a pleural fluid cytology sample was sent which was suggestive of tubercular empyema and the patient was promptly initiated on anti-tubercular treatment to which she responded well and showed clinical and radiological improvements.

Miliary Tuberculosis with Acute Respiratory Distress Syndrome: A Deadly Combination.

A unique and deadly presentation of miliary tuberculosis is acute respiratory distress syndrome. In this case report, we present the case of a 22-year-old male patient who presented with a history of weight loss, appetite loss for eight months, and rapidly worsening dyspnea for 15 days, for which he was admitted to the intensive care unit. Chest X-ray and computed tomography (CT) of the thorax revealed bilateral miliary opacities. Routine blood tests revealed hyponatremia and leukocytosis. The patient was started on non-invasive ventilatory support, intravenous corticosteroids, and anti-tubercular therapy on clinical and-radiological suspicion of miliary tuberculosis. The patient was admitted for one month and started to show rapid recovery after initiating anti-tubercular and corticosteroid therapy.

Post-tubercular Unilateral Lung Destruction: A Complicated Case.

Pulmonary tuberculosis is associated with long-term complications that affect both the respiratory and cardiovascular systems. We present the case of a 65-year-old male patient who presented with chief complaints of productive cough and breathlessness for the last four years. Further radiological investigations revealed a left-sided destroyed lung with left lung collapse and deviation of the mediastinum towards the left side. The patient responded well to treatment with broad-spectrum antimicrobial drugs and mucolytics.

Pulmonary Manifestations in Rheumatological Diseases.

Pulmonary involvement complicates the various aspects of care in patients suffering from autoimmune disorders. The epidemiological data generated over the last 10 to 15 years have improved the overall understanding of the risk factors and pathophysiological mechanisms involved in pulmonary involvement in rheumatological conditions. Recent advances in genetics have provided superior insight into the pathogenesis of autoimmune diseases and the underlying pulmonary involvement. This review article provides a concise overview of the four most common rheumatological conditions associated with pulmonary involvement: systemic lupus erythematosus (SLE), dermatomyositis/polymyositis, rheumatoid arthritis (RA), and systemic sclerosis (SSc). The clinical, epidemiological, and genetic aspects of these diseases are summarized in this article with particular emphasis on the characteristic patterns of pulmonary involvement in radiological imaging and various treatment options for each of these autoimmune diseases and their lung manifestations.

Temporal Trends in the Epidemiology of HIV in Turkey.

OBJECTIVE: The aim of this study was to analyze the temporal trends of HIV epidemiology in Turkey from 2011 to 2016. METHODS: Thirty-four teams from 28 centers at 17 different cities participated in this retrospective study. Participating centers were asked to complete a structured form containing questions about epidemiologic, demographic and clinical characteristics of patients presented with new HIV diagnosis between 2011 and 2016. Demographic data from all centers (complete or partial) were included in the analyses. For the cascade of care analysis, 15 centers that provided full data from 2011 to 2016 were included. Overall and annual distributions of the data were calculated as percentages and the Chi square test was used to determine temporal changes. RESULTS: A total of 2,953 patients between 2011 and 2016 were included. Overall male to female ratio was 5:1 with a significant increase in the number of male cases from 2011 to 2016 (p<0.001). The highest prevalence was among those aged 25-34 years followed by the 35-44 age bracket. The most common reason for HIV testing was illness (35%). While the frequency of sex among men who have sex with men increased from 16% to 30.6% (p<0.001) over the study period, heterosexual intercourse (53%) was found to be the most common transmission route. Overall, 29% of the cases presented with a CD4 count of >500 cells/mm3 while 46.7% presented with a CD4 T cell count of <350 cells/mm3. Among newly diagnosed cases, 79% were retained in care, and all such cases initiated ART with 73% achieving viral suppression after six months of antiretroviral therapy. CONCLUSION: The epidemiologic profile of HIV infected individuals is changing rapidly in Turkey with an increasing trend in the number of newly diagnosed people disclosing themselves as MSM. New diagnoses were mostly at a young age. The late diagnosis was found to be a challenging issue. Despite the unavailability of data for the first 90, Turkey is close to the last two steps of 90-90-90 targets.

Some biochemical properties of delta-aminolevulinic acid dehydratase in Gammarus pulex.

The determination of delta-aminolevulinic acid dehydratase (ALAD; porphobilinogen synthetase, EC 4.2.1.24) activity in aquatic organisms might be a useful marker for the identification of lead exposure. ALADs from the variety of different sources have been grouped into two classes based on some biochemical properties such as molecular weight, pH optimum, metal requirement and susceptibility to EDTA. The first group includes the enzymes from mammals and birds, while the second group ALADs are derived primarily from bacteria and yeasts. In this study, we have characterized Gammarus ALAD in some biochemical aspects. Gammarus pulex were collected from the Porsuk River at Eskisehir (Turkey). The effect of pH, incubation temperature of reaction mixture, incubation period, metal ions and EDTA on enzyme activity were investigated. Comparisons between groups were performed by analysis of a paired t-test. Gammarus ALAD was found biochemically distinct from the mammalian enzyme. It seems to be considered in Class II rather than Class I.

Imaging features and transcatheter treatment of a giant pulmonary arteriovenous malformation in an elderly patient.

Pulmonary arteriovenous malformations (PAVMs) comprise an anomalous communication between the pulmonary arterial and systemic circulation. The drainage is usually into one of the pulmonary veins, although rare instances of direct drainage into the left atrium or inferior vena cava have been reported. The result is a high-flow, low-resistance, right-toleft shunt. Although considered uncommon, PAVMs are being diagnosed with increasing frequency in this era of enhanced cross-sectional imaging with CT for lung screening. There is a strong association between PAVMs and hereditary haemorrhagic telangiectasia (HHT); PAVMs are more commonly found in females, with a female to male ratio of 8:1. These have varying clinical presentation, with most symptomatic PAVMs being diagnosed in the first three decades of life. The most common mode of presentation is dyspnoea on exertion. Other reported symptoms are epistaxis, chest pain, cough and, in the event of rupture, haemoptysis. Endocarditis, stroke and brain abscess formation occur frequently in patients with undiagnosed HHT with PAVMs. A 76-year-old female, with a presumed clinical diagnosis of asthma, presented to the emergency department with worsening shortness of breath. The imaging studies revealed a giant PAVM and a radionuclide scan demonstrated a large right-to-left shunt, likely accounting for her symptoms. She underwent successful transcatheter embolization (TCE) with a vascular plug performed by the interventional radiology team. The aim of this case report is to describe the imaging findings and TCE treatment of a giant PAVM.

Genome-wide analysis implicates microRNAs and their target genes in the development of bipolar disorder.

Bipolar disorder (BD) is a severe and highly heritable neuropsychiatric disorder with a lifetime prevalence of 1%. Molecular genetic studies have identified the first BD susceptibility genes. However, the disease pathways remain largely unknown. Accumulating evidence suggests that microRNAs, a class of small noncoding RNAs, contribute to basic mechanisms underlying brain development and plasticity, suggesting their possible involvement in the pathogenesis of several psychiatric disorders, including BD. In the present study, gene-based analyses were performed for all known autosomal microRNAs using the largest genome-wide association data set of BD to date (9747 patients and 14 278 controls). Associated and brain-expressed microRNAs were then investigated in target gene and pathway analyses. Functional analyses of miR-499 and miR-708 were performed in rat hippocampal neurons. Ninety-eight of the six hundred nine investigated microRNAs showed nominally significant P-values, suggesting that BD-associated microRNAs might be enriched within known microRNA loci. After correction for multiple testing, nine microRNAs showed a significant association with BD. The most promising were miR-499, miR-708 and miR-1908. Target gene and pathway analyses revealed 18 significant canonical pathways, including brain development and neuron projection. For miR-499, four Bonferroni-corrected significant target genes were identified, including the genome-wide risk gene for psychiatric disorder CACNB2. First results of functional analyses in rat hippocampal neurons neither revealed nor excluded a major contribution of miR-499 or miR-708 to dendritic spine morphogenesis. The present results suggest that research is warranted to elucidate the precise involvement of microRNAs and their downstream pathways in BD.

[The mutagenic effects of sodium nitrite and monosodium glutamate used as food additives demonstrated by the Salmonella microsome test system]. / Gida katki maddelerinden sodyum nitrit ve monosodyum glutamatin Salmonella/mikrozom test sistemiyle mutajenik etkilerinin arastirilmasi.

In this study, the mutagenicity of sodium nitrite (an antimicrobial agent) and monosodium glutamate (a flavoring agent), which are widely used as food additives, have been evaluated. They were tested for mutagenicity in the Salmonella/microsome test system by employing plate-incorporation test in the absence and presence of rat-liver fraction, S 9. No mutagenic activity was seen for monosodium glutamate in the Salmonella/microsome test system by using the tester strains Salmonella typhimurium TA98, TA100, TA1535 and TA1538. Sodium nitrite was found mutagenic on S. typhimurium TA1535, whereas it was found weakly mutagenic on S. typhimurium TA100, in the presence and absence of rat-liver fraction, S 9.

[Mutagenicity testing of some azo dyes used as food additives]. / Gidalara katilan bazi azo boyalarinin mutajenik etkilerinin test edilmesi.

The mutagenicity of 4 azo dyes (Ponceau 4R, Amaranth, Sunset Yellow FCF and Tartrazine) that are widely used to color food has been evaluated. They were tested for mutagenicity in the Salmonella typhimurium plate-incorporation and preincubation assays. The standard plate-incorporation and preincubation assays performed directly on the dyes in the absence and presence of rat-liver S9. No mutagenic activity was seen for any of the azo dyes tested by using the standard tester strains, TA 98 and TA 100.