Advanced oxidation processes for phthalate esters removal in aqueous solution: a systematic review.

This study addresses a systematic review of the scientific literature to evaluate the most common advanced oxidation processes (AOP) for the removal of phthalate esters (PE) in aqueous matrices. Six AOP were reviewed for PE degradation such as processes based on photolysis, Fenton, ozonation and sulfate radicals ( SO 4 • - ), combined AOP and other processes. The PE degradation efficiencies by AOP processes ranged from 40.3 to 100%. In the reviewed literature, an initial PE concentration within 0.04-250 mg/L was applied. The H2O2 concentrations used in the UV/H2O2 process and O3 concentrations in ozonation-based processes ranged between 0.85-1,360.6 mg/L and 2-4,971 mg/L, respectively. Based on the reported results, the PE oxidation data fit well to the pseudo-first order kinetic model. A review of the studies revealed that many oxidant species are produced in the AOP, including hydroxyl radicals (•OH), SO 4 • - , superoxide radical anions ( O 2 - • ), hydroperoxyl radicals (HO2 •), hydrogen peroxide (H2O2), and singlet oxygen (O2). Among these oxidants, •OH play a key role in the degradation of PE. However, SO 4 • - are more effective and efficient than •OH since SO 4 • - has a higher oxidation power (E = 2.5-3.1 V) compared to •OH radicals (E = 1.8-2.7 V). In different AOP processes, the aromatic rings of PE are destroyed by •OH and produce intermediates such as phthalic acid (C6H4(CO2H)2), benzoic acid ethyl ester (C9H10O2), 2, 5-dihydroxybenzoic acid (C7H6O4), formic acid (CH2O2), acetic acid (CH3COOH), and oxalic acid (C2H2O4), among some others. Until now, limited data have been reported on PE toxicity assessment. The reviewed literature has shown that AOP can be used effectively to degrade PE from aqueous matrices. However, this systematic study suggests focusing more on the evaluation of the toxicity of the effluent resulting from AOP for the decomposition of PE in future studies.

Human occupational exposure to microplastics: A cross-sectional study in a plastic products manufacturing plant.

Microplastics are ubiquitous in the natural environment, and their potential impact on health is a key issue of concern. Investigating exposure routes in humans and other living organisms is among the major challenges of microplastics. This study aims to examine the exposure level of plastic factory staff to microplastic particles before and after work shifts through body receptors (hand and facial skin, saliva and hair) in Sirjan, southeast of Iran. Moreover, the effect of face masks, gloves, cosmetics (e.g: face powder cream, lipstick and eye makeup products) and appearance on the exposure level is investigated. In total, 19 individuals are selected during six working days. Then, the collected samples are transferred to the laboratory for filtration, extraction, identification and counting of microplastic particles. Moreover, 4802 microplastic particles (100-5000 µm in size) in strand, polyhedral and spherical shapes and color spectra of white/transparent, black, blue/green, red and purple are observed. The nature of most of the observed samples is fiber with a size ≥1000 µm. Analyzing the selected samples using micro-Raman spectroscopy indicate polyester and nylon are the main identified fibers. Hair and saliva samples have the highest and lowest number of microplastics, respectively. Using gloves and sunscreen among all the participants, wearing a scarf and hair size among women and having a beard and mustache among men could have an effective role in the exposure level to microplastics. Results of this study could reveal the exposure route to microplastic particles in the human body and highlight the importance of providing higher protection to reduce exposure.

Heavy metals in edible red soil of the rainbow island in the Persian gulf: Concentration and health risk assessment.

Red soil of Hormuz Island has become a tourist attraction and it has various industrial applications. Despite the uncertainty of the health effects, geophagy is one of the common ways of people exposure to the red soil. This soil is widely used as a local spice and plays an important role in the food culture of the region. This study aimed to quantify the level of selected heavy metals (Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, V, Zn, Ag, Cd, Hg) in the red soil. The content of the metals was measured by ICP-MS (inductively coupled plasma-mass spectrometry). Moreover, risk assessment via heavy metals was carried out by computing the values of Total Hazard Quotient (THQ) and Hazard Index (HI). The results of this study showed that Fe was the most abundant metal among all analyzed metals and the health risk associated with Fe was individually higher than other measured metals. Altough the value for total heavy metals toxicity assessment was found lower than 1 , due to increasing use of red soil as a spice among Hormuz island natives, establishing special industries in order to reducing the amount of heavy metals content in red soil is recommended.

Using biomonitoring as a complementary approach in BTEX exposure assessment in the general population and occupational settings: a systematic review and meta-analysis.

Hazardous organic compounds such as benzene, toluene, ethylbenzene, o-xylene, m-xylene, and p-xylene (known as BTEX) found at work and at home can cause adverse health effects of human beings throughout their lives. Biological monitoring, an exposure assessment method, considers all exposed organic and non-organic compounds. Our goal was to perform a systematic review and a statistical analysis (meta-analysis) of peer-reviewed publications to assess urinary concentrations of BTEX biomarkers in both occupationally-exposed population and the general population. Several major electronic databases, including Scopus, Embase, Medline, Web of Science, and Google scholar (grey literature), were searched for biomonitoring studies of BTEX. Overall, 33 studies met the eligible criteria for the systematic review and six met the full inclusion criteria for meta-analysis. For meta-analysis, we included studies in which unmetabolized BTEX compounds were measured in urine samples. Due to insufficient data, studies that measured BTEX metabolites in urine samples and unmetabolized BTEX compounds in blood samples were excluded from the meta-analysis but were analyzed in the qualitative synthesis. Most studies showed increased urinary concentrations of BTEX in exposed individuals (mainly workers) compared to unexposed individuals. The results showed that the highest total BTEX concentrations were recorded in painters and policemen. This study showed that the undoubted associations between lifestyle and environmental factors and urinary levels of BTEX or its metabolites have not yet been confirmed in current biomonitoring studies. This is attributed to the few studies reported in this research area, the lack of homogeneous information, and the disagreement in the published results of the studies.

Paraquat induced oxidative stress, DNA damage, and cytotoxicity in lymphocytes.

Paraquat (PQ) is a herbicide belonging to the group of bipyridylium salts. The objective of this study was to evaluate oxidative stress, DNA damage, and cytotoxicity induced by paraquat in peripheral lymphocyte cells in vivo as well as pathological changes in various tissues. For this purpose, 28 male Wistar rats in 6 different groups were poisoned by paraquat gavage and blood samples were taken from the hearts of rats after during the poisoning period. Oxidative stress, DNA damage, cell membrane integrity, serum lactate dehydrogenase, and cytotoxicity, were investigated by Ferric Reducing Antioxidant Potential (FRAP) test, alkaline comet assay, measuring serum lactate dehydrogenase (LDH), Hoechst staining and flow cytometry with propidium iodide (PI) respectively. The lung, kidney, and liver tissues were also examined pathologically. Paraquat caused dose-dependent DNA damage in peripheral lymphocyte cells and significant oxidative cell membrane damage. The most damage was caused by a single dose of 200 mg/kg b.w of paraquat by gavage. The gradual exposure to a dose of 300 mg/kg b.w of paraquat showed less damage, which could be due to the activation of the antioxidant defense mechanism.

Health consequences of disinfection against SARS-CoV-2: Exploring oxidative stress damage using a biomonitoring approach.

Individuals who get involved in the disinfection of public settings using sodium hypochlorite might suffer adverse health effects. However, scarce information is available on the potential oxidative stress damage caused at low concentrations typically used for disinfection. We aimed to assess whether exposure to sodium hypochlorite during the COVID-19 pandemic causes oxidative stress damage in workers engaged in disinfection tasks. 75 operators engaged in the disinfection of public places were recruited as the case group, and 60 individuals who were not exposed to disinfectant were chosen as the control group. Spot urine samples were collected before (BE) and after exposure (AE) to disinfectants in the case group. Likewise, controls provided two spot urine samples in the same way as the case group. Urinary malondialdehyde (MDA) levels were quantified by forming thiobarbituric acid reactive substances in the urine. In addition, the concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in the urine was determined using an ELISA kit. Results showed significant differences in the urinary levels of oxidative stress markers, where median 8-OHdG (AE case: 3.84 ± 2.89 µg/g creatinine vs AE control 2.54 ± 1.21 µg/g creatinine) and MDA (AE case: 169 ± 89 µg/g creatinine vs AE control 121 ± 47 µg/g creatinine) levels in case group AE samples were 1.55 and 1.35-times higher than the control group AE samples (P < 0.05), respectively. Besides, urinary levels of oxidative stress markers in AE samples of the case group were significantly higher than in BE samples (8-OHdG BE 3.40 ± 1.95 µg/g creatinine, MDA BE 136 ± 51.3 µg/g creatinine, P < 0.05). Our results indicated that exposure to even low levels of sodium hypochlorite used in disinfection practices might cause oxidative stress related damage. With this in mind, implementing robust protective measures, such as specific respirators, is crucial to reduce the health burdens of exposure to disinfectants.

Exploring urinary biomarkers to assess oxidative DNA damage resulting from BTEX exposure in street children.

Children are highly susceptible to environmental contaminants as their physiology and some metabolic pathways differ from adults. The present cross-sectional study aimed to assess whether exposure to benzene, toluene, ethylbenzene, o,p-xylene, and m-xylene (BTEX) affects oxidative DNA damage in street children using a biomonitoring approach. Thirty-five boys (7-13 years of age), exposed by working at a busy intersection, and 25 unexposed boys of similar age and living in the neighborhood near the busy intersection were recruited. Urinary un-metabolized BTEX levels were quantified by a headspace gas chromatography-mass spectrometry (GC-MS). Urinary malonaldehyde (MDA) was measured with spectrophotometry. Sociodemographic and lifestyle conditions information was collected by interviews using administered questionnaires. Exposed subjects provided urine before (BE) and after work exposure (AE), while unexposed boys gave a single morning sample. Urinary BTEX concentrations in BE samples were similar to unexposed. Concentrations in AE samples were 2.36-fold higher than observed in BE samples (p < 0.05) and higher than those in the unexposed group (p < 0.05). In addition, urinary MDA levels in AE samples were 3.2 and 3.07-times higher than in BE samples and in the unexposed group (p < 0.05). Environmental tobacco smoke (ETS) increased urinary BTEX and MDA levels in both groups. Our findings confirm that street children working at busy intersections are significantly exposed to BTEX, which is associated with oxidative stress. Implementing protective measures is crucial to reduce exposure and to improve health outcomes in this group.

Assessing oxidative stress resulting from environmental exposure to metals (Oids) in a middle Eastern population.

Concentrations of metals and metalloids derived mainly from anthropogenic activities have increased considerably in the environment. Metals might be associated with increase reactive oxygen species (ROS) damage, potentially related to several health outcomes. This study has recruited 200 adult participants, including 110 males and 90 females in Shiraz (Iran), to investigate the relationship between chronic exposure to metals and ROS damage by analyzing malondialdehyde (MDA) and 8-Oxo-2'-deoxyguanosine (8-OHdG) concentrations, and has evaluated the associations between chronic metal exposure and ROS damage using regression analysis. Our findings showed participants are chronically exposed to elevate As, Ni, Hg, and Pb levels. The mean urinary concentrations of 8-OHdG and MDA were 3.8 ± 2.35 and 214 ± 134 µg/g creatinine, respectively. This study shows that most heavy metals are correlated with urinary ROS biomarkers (R ranges 0.19 to 0.64). In addition, regression analysis accounting for other confounding factors such as sex, age, smoking status, and teeth filling with amalgam highlights that Al, Cu, Si and Sn are associated with 8-OHdG concentrations, while an association between Cr and MDA and 8-OHdG is suggested. Smoking cigarettes and water-pipe is considered a significant contributory factor for both ROS biomarkers (MDA and 8-OHdG).

Assessment of fungal bioaerosols and particulate matter characteristics in indoor and outdoor air of veterinary clinics.

Veterinary staff are frequently exposed to various occupational hazards. The present study was aimed to investigate the air characteristics of veterinary clinics in terms of fungal bioaerosols and particulate matters. Air samples were taken every six days from the operating room, examination room and outdoor air of three veterinary clinics in Shiraz, southwest Iran. The concentrations of fungal bio-aerosols ranged from 8.05 CFU/m 3 in the outdoor air of clinic B to 47.21 CFU/m 3 in the operating room of clinic A. The predominant fungal genera identified in the studied clinics were Penicillium and Aspergillus niger, respectively. The concentrations of PM2.5 ranged from 41.88 µg/m 3 in the operating room of clinic C to 60.31 µg/m 3 in the outdoor air of the same clinic. The corresponding values for PM10 ranged from 114.40 µg/m 3 in the operating room of clinic C to 256.70 µg/m 3 in the outdoor air of the same clinic. The results of this study showed a positive correlation between the concentration of fungal bioaerosols and relative humidity (p < 0.05; r = 0.622). Besides, a negative correlation was found between the concentration of fungal bioaerosols and temperature (p < 0.05; r = 0.369). To better assess the individual exposure of veterinarians and staff in veterinary clinics, tests including nasopharyngeal sampling are recommended.

Microplastics in the Lut and Kavir Deserts, Iran.

Although microplastics (MPs) are ubiquitous environmental contaminants, little is known about their occurrence and behavior in the terrestrial setting. In this study, MPs have been isolated from soils collected from various geomorphological features (yardangs, sand dunes, moving sands, seasonal lakes) of the Kavir and Lut Deserts on the Iranian plateau. The number of MPs identified in 300 g samples ranged from zero (not detected) in several yardang tops to 25 on some yardang hillsides, with an overall average abundance of about 0.02 MP g-1. The majority of MPs were of a fibrous nature with a size distribution (≤100 µm to ≥1000 µm) skewed toward the lower end, and analysis of a selection of particles by µ-Raman spectroscopy showed that polyethylene terephthalate and Nylon (polyamide) were the principal polymers. Scanning electron microscopy revealed intense degradation of some particles but limited weathering of others. With little evidence of meso- and macroplastics in the deserts, it appears that the majority of MPs are brought into these environments from distant sources via the wind, with smaller, seasonal contributions from runoff associated with the adjacent mountains. It is proposed that some windborne MPs are transported through the deserts relatively rapidly, while others are subject to internal recycling and significant photo-oxidation and mechanical weathering.

Chlorpyrifos remediation in agriculture runoff with homogeneous solar photo-Fenton reaction at near neutral pH: phytotoxicity assessment.

This study represents the first application of Fe-citrate-based photo-Fenton chemistry for the degradation of chlorpyrifos (CPF) spiked into agricultural runoff, and its phytotoxicity assessment. The effects of the initial CPF concentration, time and ratio of Fe-citrate/H2O2 on CPF removal during the photo-Fenton reaction were investigated and modeled with analysis of variance using R software by the response-surface methodology package. According to the stationary point in original units, the optimal condition for 70.00% CPF removal was as follows: CPF = 2.5 mg L-1 (0.0), time = 48.0 min (0.585) and Fe-citrate/H2O2 = 0.075 (0.539). Beside running the system at near-neutral pH, another strength of this study is related to the treatment of agricultural runoff contaminated with CPF with a raceway pond reactor, which has the advantages of simplicity of the facilities and procedures, as well as the possibility of using sunlight more efficiently in the field of applications. Finally, untreated and treated agriculture runoffs were used as irrigation to determine their phytotoxic effects on seed germination of cress (Lepidium sativum). Solar photo-Fenton treatment greatly reduced phytotoxicity of agriculture runoff and showed the highest germination percentage (70%) compared to both raw agricultural runoff (60%) and untreated CPF-spiked runoff (35%).

Clinical Trials in Management of Anaplastic Thyroid Carcinoma; Progressions and Set Backs: A Systematic Review.

CONTEXT: Anaplastic thyroid carcinoma (ATC) is associated with rapid tumor growth and extremely poor prognosis. Although ATC is found in only 2% of all thyroid carcinomas, it accounts for up to 50% of thyroid cancer mortality. OBJECTIVE: To understand the effect of different treatment modalities upon anaplastic thyroid cancer outcomes. METHODS: A systematic review of studies from 1995 to 2017 was performed employing the search terms "anaplastic thyroid" and "treatment" in PubMed. Studies comparing patients receiving any type of therapy for ATC and measuring either survival as primary outcome or the percentage of patient surviving more than 1 year as secondary outcome were included for review. We did not limit sample size or subject condition. A total of 40 articles were returned from our database search, of which 25 met the inclusion criteria. RESULTS: A review of the 25 published studies indicated that early multidisciplinary approaches using extensive radical surgery, in combination with adjuvant chemo-radiation using either docetaxel/pacitaxel or cisplatin, provided the best chance of disease control. Targeted multi-tyrosine kinases inhibitors helped to limit disease progression. Also, the finding of foci of differentiated thyroid cancer within the anaplastic tumor was associated with increased long-term survival. CONCLUSIONS: ATC remains a fatal disease. Despite aggressive therapy the median survival has not significantly changed over the last 20 years. However, the percentage of patients surviving longer than 1 year continues to increase. Novel approaches incorporating multiple targeted therapy and immune therapies are critically needed.

Lifestyle and occupational factors affecting exposure to BTEX in municipal solid waste composting facility workers.

Composting facilities workers are potentially exposed to different volatile organic compounds (VOCs). This study aims to investigate the potential exposure to benzene, toluene, ethylbenzene and xylenes (BTEX) compounds among workers of composting facilities by measuring un-metabolized BTEX in urine and to investigate the effect that several lifestyle factors (i.e. smoking and residential traffic), using personal protective equipment, and religious practices such as Ramadan fasting can have on the urinary BTEX concentrations. We assessed concentrations of BTEX in the urine of a composting facility workers. Samples were collected in May 2018. Overall, 25 workers chosen as the exposed group and 20 inhabitants living close to the composting facility as a control group. The urine samples were collected from studied subjects. Identification and quantification of un-metabolized BTEX was performed using a headspace gas chromatography-mass spectrometry (GC-MS). Detailed information of participants was gathered by a comprehensive questionnaire. The geometric mean levels of urinary benzene, toluene, ethylbenzene, m­p xylene, and o­xylene in the exposed subjects were 1.27, 2.12, 0.54, 1.22 and 1.51 µg/L, respectively; 1.4 to 3.7-time higher than values in control group (p < 0.05). Post-shift levels were significantly higher than pre-shift for all chemicals (p < 0.05). Smoking habits, exposure to environmental tobacco smoke, and Ramadan fasting predicted urinary BTEX levels. Personal protective equipment which included a simple N95 mask did not protected workers from BTEX emissions. Composting facilities represent a significant source BTEX emissions and exposure for staff. More effective protective strategies are required to minimize exposure and related occupational hazards.

Response surface methodology modeling to improve degradation of Chlorpyrifos in agriculture runoff using TiO2 solar photocatalytic in a raceway pond reactor.

This paper deals with the use of a raceway pond reactor (RPR) as an alternative photoreactor for solar photocatalytic applications. Raceway pond reactors are common low-cost reactors which can treat large volumes of water. The experiments were carried out with TiO2 in the agriculture effluent spiked with Chlorpyrifos (CPF) at circumneutral pH. The Response Surface Methodology (RSM) was used to find the optimum process parameters to maximize CPF oxidation from the mathematical model equations developed in this study using R software. By ANOVA, p-value of lack of fit > 0.05 indicated that, the equation was well-fitted. The theoretical efficiency of CPF removal, under the optimum oxidation conditions with UV solar energy of around 697 ± 5.33 lux, was 84.01%, which is in close agreement with the mean experimental value (80 ± 1.42%) confirming that the response model was suitable for the optimization. As far as the authors know, this is the first study of CPF removal using RPR in agriculture runoff at circumneutral pH.

Pulmonary rehabilitation improves only some domains of health-related quality of life measured by the Short Form-36 questionnaire.

BACKGROUND: Pulmonary rehabilitation (PR) has inconsistent effects on health-related quality of life (HRQL) in patients with chronic lung diseases. We evaluated the effect of PR on HRQL outcomes using the 36-item short form of the medical outcomes (SF-36). METHODS: We retrospectively reviewed the files of all patients who completed PR in 2010, 2011, and first half of 2012. We collected information on demographics, symptoms, pulmonary function tests, 6-minute walk tests (6-MWT), and responses on the SF-36 survey, including the physical component score (PCS) and mental component score (MCS). RESULTS: The study included 19 women and 22 men. The mean age was 69.8 ± 8.5 years. The diagnoses included chronic obstructive pulmonary disease (COPD; n = 31), asthma (n = 3), interstitial lung disease (n = 5), and obstructive sleep apnea (OSA; n = 2). The mean forced expiratory volume-one second (FEV1) was 1.16 ± 0.52 L (against 60.5 ± 15.9% of predicted value). There was a significant improvement in 6-MWT (P < 0.0001). The PCS improved post-PR from 33.8 to 34.5 (P = 0.02); the MCS did not change. CONCLUSION: These patients had low SF-36 scores compared to the general population; changes in scores after PR were low. These patients may need frequent HRQL assessment during rehabilitation, and PR programs should consider program modification in patients with small changes in mental health.

The repeatability of gait speed and physiological cost index measurements in working adults.

OBJECTIVES: To determine the performance characteristics of gait speed measurements and the physiological cost index (PCI; heart rate change/gait speed) in working adults. METHODS: Gait speeds, heart rate changes, and non-steady state PCIs were calculated in 61 volunteers who worked in our health sciences center. These subjects completed 9 separate 100-foot walk tests in 3 separate sessions. RESULTS: The mean heart rate change after a 100-foot walk was 16.6 ± 8.1 beats per minute. The mean gait speed was 76.1 ± 9.6 meters per minute, and the mean PCI was 0.22 ± 0.11 beats per meter. There were highly significant correlations among all measurements on the 9 separate tests (correlation coefficients 0.41-0.95); gait speed measurements had the highest correlations (0.91-0.95). In a multivariable model hypertension and arthritis were associated with reduced gait speeds. CONCLUSION: Gait speed, heart rate changes, and non-steady state PCIs have good repeatability when measured over short walks. This information provides a rapid physiological assessment and a method for measuring changes in functional status in healthy subjects and most patients.

Pulmonary Rehabilitation Increases Gait Speed in Patients With Chronic Lung Diseases.

INTRODUCTION: Gait speed provides an integrated index of physical performance; changes in gait speed could reflect deterioration in the underlying medical disorder or a response to medical/surgical interventions. Slower gait speeds reflect the overall level of impairment, especially in patients with chronic lung disease. METHODS: We retrospectively reviewed the medical files of 119 patients who completed the pulmonary rehabilitation program at the University Medical Center in Lubbock, Texas, and collected demographic, pulmonary function, and 6-minute walk test information. Gait speed was calculated using the 6-minute walk test information. RESULTS: The patients in this study had a mean age of 68.8 ± 10.1 years. Most patients (95) had chronic obstructive pulmonary disease/asthma. The mean forced expiratory volume in the first second of expiration (FEV1) was 1.3 ± 0.7 L (47.2% ± 19.7% predicted). The baseline gait speed was 41 ± 15 m/min before rehabilitation and 47 ± 15 m/min after rehabilitation. Baseline gait speed, body mass index, and FEV1 predicted postrehabilitation gait speed (P < .05 for each variable). Ten patients had a gait speed >60 m/min before rehabilitation; this number increased to 29 postrehabilitation. Using multivariable analysis, it was found that only the baseline gait speed predicted a speed of more than 60 m/min postrehabilitation. Seventy-four patients had an increase in 6-minute walk distance of greater than 30 m. CONCLUSIONS: Patients with chronic lung diseases have slow gait speeds. Most patients improve their speed with rehabilitation but do not increase their speed above 60 m/min and remain frail by this criterion. However, the majority of patients increase their walk distance by 30 m, a distance that represents a minimal clinically important distance.

Tuberculosis reactivation in referrals to public health clinics in Texas.

BACKGROUND: Screening for and treatment of latent tuberculosis infection (LTBI) have been essential components of the TB elimination strategy. METHODS: To estimate the rate of and to identify risk factors for reactivation TB in patients in Texas with LTBI, we retrospectively analyzed 51,959 patients with LTBI identified in Texas Department of State Health Services TB clinics from 1995 to 2008. RESULTS: We identified 200 cases of reactivation TB among the 51,959 patients in this database. The overall rate of reactivation TB was 0.038 cases per 100 person-years (95% confidence interval [CI]: 0.032-0.043). The reactivation rate in patients who did not receive a complete treatment was 0.058. The relative risk (RR) for reactivation was higher in men (RR = 1.15; 95% CI: 0.86-1.54), patients older than 50 years (RR = 1.13; 95% CI: 1.04-1.22), African American (RR = 1.21; 95% CI: 1.09-1.34), U.S.-born referrals (RR = 1.4; 95% CI: 1.11-1.76), referrals with abnormal X-rays (RR = 1.07; 95% CI: 1.03-1.12) and patients receiving treatment other than isoniazid (RR = 1.08; 95% CI: 1.03-1.13). CONCLUSIONS: The current rate of reactivation TB in Texas is much lower than rates reported in the United States in the 1950s. Certain patients are at increased risk for reactivation and should be monitored more closely during LTBI therapy.

Stand alone surgical ablation for atrial fibrillation.

BACKGROUND: Trials to maintain sinus rhythm in patients with atrial fibrillation (AF) and refractory symptoms have been complicated by lack of success or intolerance of medications. Experience with minimally invasive AF surgery is relatively new, and early results have been promising. However, the study populations and techniques were heterogeneous, and the follow-up periods were short in many series. METHODS: We present a single center experience through a retrospective review of medical records of patients who had minimally invasive AF surgery. RESULTS: The surgical techniques addressed several possible mechanisms of AF and causes of recurrence, including pulmonary vein isolation, underlying substrates modification, ligament of Marshall interruption, ganglion plexus ablation, and left atrial appendage exclusion. Thirty-three cases were identified. The mean duration of follow-up was 23.2 months, and 58.6% were maintained in a sinus rhythm and were off antiarrhythmic drugs at the end of the follow-up period. Cases with persistent AF had a lower success rate. CONCLUSION: Results with minimally invasive surgery are suboptimal at two years of follow-up, particularly for patients with persistent AF.

Oropharyngeal flora in patients admitted to the medical intensive care unit: clinical factors and acid suppressive therapy.

Acid suppression therapy in critically ill patients significantly reduces the incidence of stress ulceration and gastrointestinal (GI) bleeding; however, recent studies suggest that proton pump inhibitors (PPIs) increase the risk of pneumonia. We wanted to test the hypothesis that acid suppressive therapy promotes alteration in the bacterial flora in the GI tract and leads to colonization of the upper airway tract with pathogenic species, potentially forming the biological basis for the observed increased incidence of pneumonia in these patients. This was a prospective observational study on patients (adults 18 years or older) admitted to the medical intensive care unit (MICU) at a tertiary care centre. Exclusion criteria included all patients with a diagnosis of pneumonia at admission, with infection in the upper airway, or with a history of significant dysphagia. Oropharyngeal cultures were obtained on day 1 and days 3 or 4 of admission. We collected data on demographics, clinical information, and severity of the underlying disease using APACHE II scores. There were 110 patients enrolled in the study. The mean age was 49±16 years, 50 were women, and the mean APACHE II score was 9.8 ± 6.5. Twenty per cent of the patients had used a PPI in the month preceding admission. The first oropharyngeal specimen was available in 110 cases; a second specimen at 72-96 h was available in 68 cases. Seventy-five per cent of the patients admitted to the MICU had abnormal flora. In multivariate logistic regression, diabetes mellitus and PPI use were associated with abnormal oral flora on admission. Chronic renal failure and a higher body mass index reduced the frequency of abnormal oral flora on admission. Most critically ill patients admitted to our MICU have abnormal oral flora. Patients with diabetes and a history of recent PPI use are more likely to have abnormal oral flora on admission.