Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 100
Filter
1.
J Antimicrob Chemother ; 79(4): 859-867, 2024 04 02.
Article in English | MEDLINE | ID: mdl-38380946

ABSTRACT

BACKGROUND: In the USA, nirmatrelvir/ritonavir is authorized for the treatment of mild-to-moderate COVID-19 in patients at least 12 years of age, at high risk for progression to severe COVID-19. OBJECTIVES: To estimate the impact of outpatient nirmatrelvir/ritonavir on COVID-19 hospitalization risk in a US healthcare system. METHODS: We conducted a cohort study using electronic health records among outpatients with a positive SARS-CoV-2 PCR test between January and August 2022. We evaluated the association of nirmatrelvir/ritonavir therapy with time to hospitalization by estimating adjusted HRs and assessed the impact of nirmatrelvir/ritonavir on predicted COVID-19 hospitalizations using machine-learning methods. RESULTS: Among 44 671 patients, 4948 (11%) received nirmatrelvir/ritonavir, and 201 (0.4%) were hospitalized within 28 days of COVID-19 diagnosis. Nirmatrelvir/ritonavir recipients were more likely to be older, white, vaccinated, have comorbidities and reside in areas with higher average socioeconomic status. The 28 day cumulative incidence of hospitalization was 0.06% (95% CI: 0.02%-0.17%) among nirmatrelvir/ritonavir recipients and 0.52% (95% CI: 0.46%-0.60%) among non-recipients. For nirmatrelvir/ritonavir versus no therapy, the age-adjusted HR was 0.08 (95% CI: 0.03-0.26); the fully adjusted HR was 0.16 (95% CI: 0.05-0.50). In the machine-learning model, the primary features reducing predicted hospitalization risk were nirmatrelvir/ritonavir, younger age, vaccination, female gender and residence in a higher socioeconomic status area. CONCLUSIONS: COVID-19 hospitalization risk was reduced by 84% among nirmatrelvir/ritonavir recipients in a large, diverse healthcare system during the Omicron wave. These results suggest that nirmatrelvir/ritonavir remained highly effective in a setting substantially different than the original clinical trials.


Subject(s)
COVID-19 , Lactams , Leucine , Nitriles , Outpatients , Proline , Humans , Female , COVID-19/epidemiology , North Carolina , COVID-19 Testing , Cohort Studies , Ritonavir/therapeutic use , SARS-CoV-2 , COVID-19 Drug Treatment , Hospitalization , Antiviral Agents/therapeutic use
2.
Curr Opin Infect Dis ; 35(5): 417-423, 2022 10 01.
Article in English | MEDLINE | ID: mdl-35980005

ABSTRACT

PURPOSE OF REVIEW: Giardia is a common intestinal parasite worldwide, and infection can be associated with clear, and sometimes persistent symptomatology. However, in children in high-prevalence settings, it is most often not associated with or is perhaps even protective against acute diarrhea. Nonetheless, recent longitudinal studies in high-prevalence settings increasingly identify an association with long-term outcomes that has been difficult to discern. RECENT FINDINGS: Recent studies have made progress in disentangling this apparent paradox. First, prospective, well characterized cohort studies have repeatedly identified associations between Giardia infection, gut function, and child growth. Second, experimental animal and in-vitro models have further characterized the biological plausibility that Giardia could impair intestinal function and subsequently child development through different pathways, depending upon biological and environmental factors. Finally, new work has shed light on the potential for Giardia conspiring with specific other gut microbes, which may explain discrepant findings in the literature, help guide future higher resolution analyses of this pathogen, and inform new opportunities for intervention. SUMMARY: Recent prospective studies have confirmed a high, if not universal, prevalence of persistent Giardia infections in low-and-middle income countries associated with child-growth shortfalls and altered gut permeability. However, the predominance of subclinical infections limits understanding of the true clinical impact of endemic pediatric giardiasis, and global disease burdens remain uncalculated. Integrating the role of Giardia in multipathogen enteropathies and how nutritional, microbial, metabolic, and pathogen-strain variables influence Giardia infection outcomes could sharpen delineations between pathogenic and potentially beneficial attributes of this enigmatic parasite.


Subject(s)
Giardiasis , Animals , Diarrhea/epidemiology , Diarrhea/etiology , Giardia , Giardiasis/complications , Giardiasis/epidemiology , Giardiasis/parasitology , Humans , Incidence , Prevalence , Prospective Studies
3.
Epidemiol Infect ; 150: e20, 2022 01 07.
Article in English | MEDLINE | ID: mdl-35068405

ABSTRACT

Serosurveillance is an important epidemiologic tool for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), used to estimate infection rates and the degree of population immunity. There is no general agreement on which antibody biomarker(s) should be used, especially with the rollout of vaccines globally. Here, we used random forest models to demonstrate that a single spike or receptor-binding domain (RBD) antibody was adequate for classifying prior infection, while a combination of two antibody biomarkers performed better than any single marker for estimating time-since-infection. Nucleocapsid antibodies performed worse than spike or RBD antibodies for classification, but can be useful for estimating time-since-infection, and in distinguishing infection-induced from vaccine-induced responses. Our analysis has the potential to inform the design of serosurveys for SARS-CoV-2, including decisions regarding a number of antibody biomarkers measured.


Subject(s)
Antibodies, Viral/blood , COVID-19/epidemiology , SARS-CoV-2/immunology , Adult , Aged , Aged, 80 and over , Biomarkers , Female , Humans , Immunoglobulin G/blood , Male , Middle Aged , Seroepidemiologic Studies , Spike Glycoprotein, Coronavirus/immunology , Time Factors
4.
Clin Radiol ; 77(9): 650-654, 2022 09.
Article in English | MEDLINE | ID: mdl-35659770

ABSTRACT

AIM: To assess the rates of breast cancer detected in postoperative surveillance mammograms in women >70 Years and overall mortality in this age group. MATERIALS AND METHODS: Four hundred and ninety-eight patients were identified retrospectively from a database from a single large UK hospital. Patients were included in the study if they were female, aged >70 years at diagnosis of either invasive breast cancer or ductal carcinoma in situ (DCIS), had surgical treatment between 1 January 2010 and 31 December 2014, and no previous diagnosis of breast cancer. Statistical analysis was performed using Excel, using the X2 test, with p ≤ 0.05 considered statistically significant. RESULTS: The mean age of women included in this study was 77 years. The mean number of postoperative surveillance mammograms performed per patient was 4.2. In the 5-year follow-up, there was a local recurrence rate of 1.9% (n=6) and a contralateral breast cancer rate of 1% (n=6). The 5-year overall mortality rate was 17.7% (n=88), and the 5-year breast cancer-specific mortality rate was 7.2% (n=36). CONCLUSION: This study demonstrated low local recurrence and contralateral breast cancer rates during the 5-year follow-up period. Clear discussions therefore need to be held with older patients about the value of postoperative mammographic surveillance. Further research is required regarding patient opinion and experience to help develop more consistent guidelines.


Subject(s)
Breast Neoplasms , Cancer Survivors , Carcinoma, Intraductal, Noninfiltrating , Aged , Aged, 80 and over , Breast Neoplasms/pathology , Carcinoma, Intraductal, Noninfiltrating/pathology , Female , Humans , Male , Mammography , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Recurrence, Local/pathology , Retrospective Studies
5.
Ann Intern Med ; 174(6): 737-746, 2021 06.
Article in English | MEDLINE | ID: mdl-33617725

ABSTRACT

BACKGROUND: Outpatient diverticulitis is commonly treated with either a combination of metronidazole and a fluoroquinolone (metronidazole-with-fluoroquinolone) or amoxicillin-clavulanate alone. The U.S. Food and Drug Administration advised that fluoroquinolones be reserved for conditions with no alternative treatment options. The comparative effectiveness of metronidazole-with-fluoroquinolone versus amoxicillin-clavulanate for diverticulitis is uncertain. OBJECTIVE: To determine the effectiveness and harms of metronidazole-with-fluoroquinolone versus amoxicillin-clavulanate for outpatient diverticulitis. DESIGN: Active-comparator, new-user, retrospective cohort studies. SETTING: Nationwide population-based claims data on U.S. residents aged 18 to 64 years with private employer-sponsored insurance (2000 to 2018) or those aged 65 years or older with Medicare (2006 to 2015). PARTICIPANTS: Immunocompetent adults with diverticulitis in the outpatient setting. INTERVENTION: Metronidazole-with-fluoroquinolone or amoxicillin-clavulanate. MEASUREMENTS: 1-year risks for inpatient admission, urgent surgery, and Clostridioides difficile infection (CDI) and 3-year risk for elective surgery. RESULTS: In MarketScan (IBM Watson Health), new users of metronidazole-with-fluoroquinolone (n = 106 361) and amoxicillin-clavulanate (n = 13 160) were identified. There were no differences in 1-year admission risk (risk difference, 0.1 percentage points [95% CI, -0.3 to 0.6]), 1-year urgent surgery risk (risk difference, 0.0 percentage points [CI, -0.1 to 0.1]), 3-year elective surgery risk (risk difference, 0.2 percentage points [CI, -0.3 to 0.7]), or 1-year CDI risk (risk difference, 0.0 percentage points [CI, -0.1 to 0.1]) between groups. In Medicare, new users of metronidazole-with-fluoroquinolone (n = 17 639) and amoxicillin-clavulanate (n = 2709) were identified. There were no differences in 1-year admission risk (risk difference, 0.1 percentage points [CI, -0.7 to 0.9]), 1-year urgent surgery risk (risk difference, -0.2 percentage points [CI, -0.6 to 0.1]), or 3-year elective surgery risk (risk difference, -0.3 percentage points [CI, -1.1 to 0.4]) between groups. The 1-year CDI risk was higher for metronidazole-with-fluoroquinolone than for amoxicillin-clavulanate (risk difference, 0.6 percentage points [CI, 0.2 to 1.0]). LIMITATION: Residual confounding is possible, and not all harms associated with these antibiotics, most notably drug-induced liver injury, could be assessed. CONCLUSION: Treating diverticulitis in the outpatient setting with amoxicillin-clavulanate may reduce the risk for fluoroquinolone-related harms without adversely affecting diverticulitis-specific outcomes. PRIMARY FUNDING SOURCE: National Institutes of Health.


Subject(s)
Ambulatory Care , Amoxicillin-Potassium Clavulanate Combination/therapeutic use , Anti-Bacterial Agents/therapeutic use , Diverticulitis/drug therapy , Fluoroquinolones/therapeutic use , Metronidazole/therapeutic use , Adolescent , Adult , Amoxicillin-Potassium Clavulanate Combination/adverse effects , Anti-Bacterial Agents/adverse effects , Clostridium Infections/diagnosis , Comparative Effectiveness Research , Cost of Illness , Diverticulitis/surgery , Female , Fluoroquinolones/adverse effects , Hospitalization , Humans , Male , Metronidazole/adverse effects , Middle Aged , Retrospective Studies , Risk Factors , Young Adult
6.
Clin Infect Dis ; 73(7): e1754-e1757, 2021 10 05.
Article in English | MEDLINE | ID: mdl-33313656

ABSTRACT

Treatment options for Achromobacter xylosoxidans are limited. Eight cystic fibrosis patients with A. xylosoxidans were treated with 12 cefiderocol courses. Pretreatment in vitro resistance was seen in 3 of 8 cases. Clinical response occurred after 11 of 12 treatment courses. However, microbiologic relapse was observed after 11 of 12 treatment courses, notably without emergence of resistance.


Subject(s)
Achromobacter denitrificans , Cystic Fibrosis , Gram-Negative Bacterial Infections , Adult , Anti-Bacterial Agents/therapeutic use , Cephalosporins , Child , Cystic Fibrosis/complications , Cystic Fibrosis/drug therapy , Gram-Negative Bacterial Infections/drug therapy , Humans , Cefiderocol
7.
Transpl Infect Dis ; 23(1): e13452, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32869901

ABSTRACT

Sulfonamides are recommended as part of first-line therapy for most Nocardia infections, with trimethoprim-sulfamethoxazole (TMP-SMX) considered the drug of choice for susceptible isolates. However, in the case of central nervous system, disseminated disease, and other serious Nocardia infections, TMP-SMX should not be used as monotherapy. The preferred treatment for a patient unable to take TMP-SMX because of allergy or intolerance remains uncertain. Prior to the availability of TMP-SMX in 1973, other sulfonamides were mainstays of treatment. We describe a Nocardia infection successfully treated with sulfadiazine in a lung transplant recipient who could not tolerate TMP-SMX. A review of similar cases reported in the literature provides insight into the successful treatment of Nocardia infections with sulfonamide regimens not containing trimethoprim in transplant recipients and other immunocompromised hosts.


Subject(s)
Nocardia Infections , Nocardia , Humans , Immunocompromised Host , Lung Transplantation , Nocardia Infections/drug therapy , Sulfonamides , Trimethoprim, Sulfamethoxazole Drug Combination
8.
PLoS Pathog ; 13(7): e1006471, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28750066

ABSTRACT

Diverse enteropathogen exposures associate with childhood malnutrition. To elucidate mechanistic pathways whereby enteric microbes interact during malnutrition, we used protein deficiency in mice to develop a new model of co-enteropathogen enteropathy. Focusing on common enteropathogens in malnourished children, Giardia lamblia and enteroaggregative Escherichia coli (EAEC), we provide new insights into intersecting pathogen-specific mechanisms that enhance malnutrition. We show for the first time that during protein malnutrition, the intestinal microbiota permits persistent Giardia colonization and simultaneously contributes to growth impairment. Despite signals of intestinal injury, such as IL1α, Giardia-infected mice lack pro-inflammatory intestinal responses, similar to endemic pediatric Giardia infections. Rather, Giardia perturbs microbial host co-metabolites of proteolysis during growth impairment, whereas host nicotinamide utilization adaptations that correspond with growth recovery increase. EAEC promotes intestinal inflammation and markers of myeloid cell activation. During co-infection, intestinal inflammatory signaling and cellular recruitment responses to EAEC are preserved together with a Giardia-mediated diminishment in myeloid cell activation. Conversely, EAEC extinguishes markers of host energy expenditure regulatory responses to Giardia, as host metabolic adaptations appear exhausted. Integrating immunologic and metabolic profiles during co-pathogen infection and malnutrition, we develop a working mechanistic model of how cumulative diet-induced and pathogen-triggered microbial perturbations result in an increasingly wasted host.


Subject(s)
Coinfection/microbiology , Coinfection/parasitology , Escherichia coli Infections/microbiology , Escherichia coli/physiology , Giardia lamblia/physiology , Giardiasis/parasitology , Malnutrition/microbiology , Malnutrition/parasitology , Animals , Child , Coinfection/immunology , Cytokines/immunology , Disease Models, Animal , Escherichia coli Infections/immunology , Giardiasis/immunology , Humans , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , Intestinal Mucosa/parasitology , Male , Malnutrition/immunology , Mice , Mice, Inbred C57BL , Myeloid Cells/immunology
9.
Arterioscler Thromb Vasc Biol ; 38(1): 275-282, 2018 01.
Article in English | MEDLINE | ID: mdl-29191927

ABSTRACT

OBJECTIVE: Exposure to mobile source emissions is nearly ubiquitous in developed nations and is associated with multiple adverse health outcomes. There is an ongoing need to understand the specificity of traffic exposure associations with vascular outcomes, particularly in individuals with cardiovascular disease. APPROACH AND RESULTS: We performed a cross-sectional study using 2124 individuals residing in North Carolina, United States, who received a cardiac catheterization at the Duke University Medical Center. Traffic-related exposure was assessed via 2 metrics: (1) the distance between the primary residence and the nearest major roadway; and (2) location of the primary residence in regions defined based on local traffic patterns. We examined 4 cardiovascular disease outcomes: hypertension, peripheral arterial disease, the number of diseased coronary vessels, and recent myocardial infarction. Statistical models were adjusted for race, sex, smoking, type 2 diabetes mellitus, body mass index, hyperlipidemia, and home value. Results are expressed in terms of the odds ratio (OR). A 23% decrease in residential distance to major roadways was associated with higher prevalence of peripheral arterial disease (OR=1.29; 95% confidence interval, 1.08-1.55) and hypertension (OR=1.15; 95% confidence interval, 1.01-1.31). Associations with peripheral arterial disease were strongest in men (OR=1.42; 95% confidence interval, 1.17-1.74) while associations with hypertension were strongest in women (OR=1.21; 95% confidence interval, 0.99-1.49). Neither myocardial infarction nor the number of diseased coronary vessels were associated with traffic exposure. CONCLUSIONS: Traffic-related exposure is associated with peripheral arterial disease and hypertension while no associations are observed for 2 coronary-specific vascular outcomes.


Subject(s)
Cardiac Catheterization , Hypertension/diagnosis , Hypertension/epidemiology , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/epidemiology , Residence Characteristics , Traffic-Related Pollution/adverse effects , Coronary Artery Disease/diagnosis , Coronary Artery Disease/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Myocardial Infarction/diagnosis , Myocardial Infarction/epidemiology , North Carolina/epidemiology , Prevalence , Risk Assessment , Risk Factors
10.
Article in English | MEDLINE | ID: mdl-30297368

ABSTRACT

Cryptosporidium species cause significant morbidity in malnourished children. Nitazoxanide (NTZ) is the only approved treatment for cryptosporidiosis, but NTZ has diminished effectiveness during malnutrition. Here, we show that amixicile, a highly selective water-soluble derivative of NTZ diminishes Cryptosporidium infection severity in a malnourished mouse model despite a lack of direct anticryptosporidial activity. We suggest that amixicile, by tamping down anaerobes associated with intestinal inflammation, reverses weight loss and indirectly mitigates infection-associated pathology.


Subject(s)
Benzamides/pharmacology , Cryptosporidiosis/drug therapy , Cryptosporidium parvum/drug effects , Thiazoles/pharmacology , Animals , Antiprotozoal Agents/pharmacology , Cryptosporidiosis/etiology , Cryptosporidium parvum/pathogenicity , Disease Models, Animal , Mice, Inbred C57BL , Nitro Compounds , Pyruvate Synthase/antagonists & inhibitors , Pyruvate Synthase/metabolism , Weight Loss/drug effects
11.
Reprod Domest Anim ; 53(4): 1016-1019, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29604142

ABSTRACT

Recent reports indicate that stimulation of liquid-stored boar semen with red LED-based light improves sperm quality and reproductive performance in sow herds. So far, in vitro data after LED stimulation of whole semen doses are lacking. In this study, the effect of LED light exposure on the in vitro quality of boar spermatozoa after storage and thermic incubation was examined. Boar semen doses were stored at 17°C (n = 10) or 5°C (n = 6) in Beltsville Thawing Solution extender and then exposed to red LED light using a commercial photo chamber. During a subsequent long-term incubation at 38°C, neither sperm kinematic parameters nor mitochondria function or membrane integrity differed between control and treated samples (p > .05). It is concluded that stimulation of semen doses in the LED-photo chamber does not improve quality of thermically stressed boar sperm in vitro. Other than the sperm traits tested here might be involved in the previously reported improvement of in vivo fertility.


Subject(s)
Hot Temperature , Light , Semen/radiation effects , Spermatozoa/radiation effects , Swine/physiology , Animals , Male , Semen Preservation , Spermatozoa/physiology , Stress, Physiological , Time Factors
13.
Atmos Environ (1994) ; 163: 99-106, 2017 Aug.
Article in English | MEDLINE | ID: mdl-30505204

ABSTRACT

A sample integrity evaluation and an interlaboratory comparison were conducted in application of U.S. Environmental Protection Agency (EPA) Methods 325A and 325B for diffusively monitoring benzene and other selected volatile organic compounds (VOCs) using Carbopack X sorbent tubes. To evaluate sample integrity, VOC samples were refrigerated for up to 240 days and analyzed using thermal desorption/gas chromatography-mass spectrometry at the EPA Office of Research and Development laboratory in Research Triangle Park, NC, USA. For the interlaboratory comparison, three commercial analytical laboratories were asked to follow Method 325B when analyzing samples of VOCs that were collected in field and laboratory settings for EPA studies. Overall results indicate that the selected VOCs collected diffusively on sorbent tubes generally were stable for 6 months or longer when samples were refrigerated. This suggests the specified maximum 30-day storage time of VOCs collected diffusively on Carbopack X passive samplers and analyzed using Method 325B might be able to be relaxed. Interlaboratory comparison results were in agreement for the challenge samples collected diffusively in an exposure chamber in the laboratory, with most measurements within ±25% of the theoretical concentration. Statistically significant differences among laboratories for ambient challenge samples were small, less than 1 part per billion by volume (ppbv). Results from all laboratories exhibited good precision and generally agreed well with each other.

14.
Clin Infect Dis ; 63(6): 792-7, 2016 09 15.
Article in English | MEDLINE | ID: mdl-27313261

ABSTRACT

BACKGROUND: Growth stunting in children under 2 years of age in low-income countries is common. Giardia is a ubiquitous pathogen in this age group but studies investigating Giardia's effect on both growth and diarrhea have produced conflicting results. METHODS: We conducted a prospective longitudinal birth cohort study in Dhaka, Bangladesh, with monthly Giardia and continuous diarrheal surveillance. RESULTS: 629 children were enrolled within the first 72 hours of life, and 445 completed 2 years of the study. 12% of children were stunted at birth with 57% stunted by 2 years. 7% of children had a Giardia positive surveillance stool in the first 6 months of life, whereas 74% had a positive stool by 2 years. The median time to first Giardia positive surveillance stool was 17 months. Presence of Giardia in a monthly surveillance stool within the first 6 months of life decreased length-for-age Z score at 2 years by 0.4 (95% confidence interval, -.80 to -.001; P value .05) whereas total number of Giardia positive months over the 2-year period of observation did not. Neither variable was associated with weight-for-age Z score at 2 years. In our model to examine predictors of diarrhea only exclusive breastfeeding was significantly associated with decreased diarrhea (P value <.001). Concomitant giardiasis was neither a risk factor nor protective. CONCLUSIONS: Early life Giardia was a risk factor for stunting at age 2 but not poor weight gain. Presence of Giardia neither increased nor decreased odds of acute all cause diarrhea.


Subject(s)
Diarrhea , Giardiasis , Bangladesh/epidemiology , Diarrhea/epidemiology , Diarrhea/parasitology , Female , Giardiasis/complications , Giardiasis/epidemiology , Growth Disorders/epidemiology , Humans , Infant , Infant, Newborn , Longitudinal Studies , Male , Prospective Studies
15.
Curr Opin Infect Dis ; 29(5): 502-7, 2016 10.
Article in English | MEDLINE | ID: mdl-27479025

ABSTRACT

PURPOSE OF REVIEW: Giardia is a common intestinal parasite worldwide, and infection can be associated with clear and sometimes persistent symptomatology. However, in children in high-prevalence settings, it is not associated with or is perhaps even protective against acute diarrhea, and the association with long-term outcomes has been difficult to discern. RECENT FINDINGS: Recent studies have made progress in helping us disentangle this apparent paradox. First, prospective, well-characterized cohort studies have added to the data on the association between Giardia and diarrhea in these settings and have further characterized associations between Giardia infection and nutrition, gut function, and growth. Second, animal models have further characterized the host response to Giardia and helped elucidate mechanisms by which Giardia could impair child development. Finally, new work has shed light on the heterogeneity of human Giardia strains, which may both explain discrepant findings in the literature and help guide higher-resolution analyses of this pathogen in the future. SUMMARY: The true clinical impact of endemic pediatric giardiasis remains unclear, but recent prospective studies have confirmed a high prevalence of persistent, subclinical Giardia infections and associated growth shortfalls. Integrating how nutritional, microbial, metabolic, and pathogen-strain variables influence these outcomes could sharpen delineations between pathogenic and potentially beneficial attributes of this enigmatic parasite.


Subject(s)
Diarrhea , Giardia , Giardiasis , Host-Parasite Interactions , Animals , Child , Child Development , Child, Preschool , Humans , Nutritional Status , Prevalence , Prospective Studies
16.
J Air Waste Manag Assoc ; 66(5): 492-8, 2016 May.
Article in English | MEDLINE | ID: mdl-26828464

ABSTRACT

UNLABELLED: Select volatile organic compounds (VOCs) were measured in the vicinity of a petroleum refinery and related operations in South Philadelphia, Pennsylvania, USA, using passive air sampling and laboratory analysis methods. Two-week, time-integrated samplers were deployed at 17 sites, which were aggregated into five site groups of varying distances from the refinery. Benzene, toluene, ethylbenzene, and xylene isomers (BTEX) and styrene concentrations were higher near the refinery's fenceline than for groups at the refinery's south edge, mid-distance, and farther removed locations. The near fenceline group was significantly higher than the refinery's north edge group for benzene and toluene but not for ethylbenzene or xylene isomers; styrene was lower at the near fenceline group versus the north edge group. For BTEX and styrene, the magnitude of estimated differences generally increased when proceeding through groups ever farther away from the petroleum refining. Perchloroethylene results were not suggestive of an influence from refining. These results suggest that emissions from the refinery complex contribute to higher concentrations of BTEX species and styrene in the vicinity of the plant, with this influence declining as distance from the petroleum refining increases. IMPLICATIONS: Passive sampling methodology for VOCs as discussed here is employed in recently enacted U.S. Environmental Protection Agency Methods 325A/B for determination of benzene concentrations at refinery fenceline locations. Spatial gradients of VOC concentration near the refinery fenceline were discerned in an area containing traffic and other VOC-related sources. Though limited, these findings can be useful in application of the method at such facilities to ascertain source influence.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring/methods , Spatial Analysis , Volatile Organic Compounds/analysis , Environmental Monitoring/instrumentation , Philadelphia
17.
J Air Waste Manag Assoc ; 66(4): 412-9, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26771215

ABSTRACT

UNLABELLED: A pilot study was conducted in application of the U.S. Environmental Protection Agency (EPA) Methods 325A/B variant for monitoring volatile organic compounds (VOCs) near two oil and natural gas (ONG) production well pads in the Texas Barnett Shale formation and Colorado Denver-Julesburg Basin (DJB), along with a traffic-dominated site in downtown Denver, CO. As indicated in the EPA method, VOC concentrations were measured for 14-day sampling periods using passive-diffusive tube samplers with Carbopack X sorbent at fenceline perimeter and other locations. VOCs were significantly higher at the DJB well pad versus the Barnett well pad and were likely due to higher production levels at the DJB well pad during the study. Benzene and toluene were significantly higher at the DJB well pad versus downtown Denver. Except for perchloroethylene, VOCs measured at passive sampler locations (PSs) along the perimeter of the Barnett well pad were significantly higher than PSs farther away. At the DJB well pad, most VOC concentrations, except perchloroethylene, were significantly higher prior to operational changes than after these changes were made. Though limited, the results suggest passive samplers are precise (duplicate precision usually ≤10%) and that they can be useful to assess spatial gradients and operational conditions at well pad locations over time-integrated periods. IMPLICATIONS: Recently enacted EPA Methods 325A/B use passive-diffusive tube samplers to measure benzene at multiple fenceline locations at petrochemical refineries. This pilot study presents initial data demonstrating the utility of Methods 325A/B for monitoring at ONG facilities. Measurements revealed elevated concentrations reflective of production levels and spatial gradients of VOCs relative to source proximity at the Barnett well pad, as well as operational changes at the DJB well pad. Though limited, these findings indicate that Methods 325A/B can be useful in application to characterize VOCs at well pad boundaries.


Subject(s)
Environmental Monitoring/methods , Oil and Gas Fields , Volatile Organic Compounds/analysis , Colorado , Pilot Projects , Texas
18.
Tech Coloproctol ; 19(7): 419-28, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26084884

ABSTRACT

BACKGROUND: Artificial neural networks (ANNs) can be used to develop predictive tools to enable the clinical decision-making process. This study aimed to investigate the use of an ANN in predicting the outcomes from enhanced recovery after colorectal cancer surgery. METHODS: Data were obtained from consecutive colorectal cancer patients undergoing laparoscopic surgery within the enhanced recovery after surgery (ERAS) program between 2002 and 2009 in a single center. The primary outcomes assessed were delayed discharge and readmission within a 30-day period. The data were analyzed using a multilayered perceptron neural network (MLPNN), and a prediction tools were created for each outcome. The results were compared with a conventional statistical method using logistic regression analysis. RESULTS: A total of 275 cancer patients were included in the study. The median length of stay was 6 days (range 2-49 days) with 67 patients (24.4 %) staying longer than 7 days. Thirty-four patients (12.5 %) were readmitted within 30 days. Important factors predicting delayed discharge were related to failure in compliance with ERAS, particularly with the postoperative elements in the first 48 h. The MLPNN for delayed discharge had an area under a receiver operator characteristic curve (AUROC) of 0.817, compared with an AUROC of 0.807 for the predictive tool developed from logistic regression analysis. Factors predicting 30-day readmission included overall compliance with the ERAS pathway and receiving neoadjuvant treatment for rectal cancer. The MLPNN for readmission had an AUROC of 0.68. CONCLUSIONS: These results may plausibly suggest that ANN can be used to develop reliable outcome predictive tools in multifactorial intervention such as ERAS. Compliance with ERAS can reliably predict both delayed discharge and 30-day readmission following laparoscopic colorectal cancer surgery.


Subject(s)
Aftercare/statistics & numerical data , Colectomy/adverse effects , Colorectal Neoplasms/surgery , Laparoscopy/adverse effects , Neural Networks, Computer , Patient Discharge/statistics & numerical data , Patient Readmission/statistics & numerical data , Aftercare/methods , Area Under Curve , Colectomy/methods , Colectomy/rehabilitation , Female , Humans , Laparoscopy/methods , Laparoscopy/rehabilitation , Length of Stay , Logistic Models , Male , Neoadjuvant Therapy/adverse effects , Neoadjuvant Therapy/statistics & numerical data , Patient Compliance/statistics & numerical data , Prospective Studies , Retrospective Studies , Time Factors
19.
bioRxiv ; 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38328247

ABSTRACT

Undernutrition in children commonly disrupts the structure and function of the small intestinal microbial community, leading to enteropathies, compromised metabolic health, and impaired growth and development. The mechanisms by which diet and microbes mediate the balance between commensal and pathogenic intestinal flora remain elusive. In a murine model of undernutrition, we investigated the direct interactions Giardia lamblia, a prevalent small intestinal pathogen, on indigenous microbiota and specifically on Lactobacillus strains known for their mucosal and growth homeostatic properties. Our research reveals that Giardia colonization shifts the balance of lactic acid bacteria, causing a relative decrease in Lactobacillus spp . and an increase in Bifidobacterium spp . This alteration corresponds with a decrease in multiple indicators of mucosal and nutritional homeostasis. Additionally, protein-deficient conditions coupled with Giardia infection exacerbate the rise of primary bile acids and susceptibility to bile acid-induced intestinal barrier damage. In epithelial cell monolayers, Lactobacillus spp . mitigated bile acid-induced permeability, showing strain-dependent protective effects. In vivo, L. plantarum, either alone or within a Lactobacillus spp consortium, facilitated growth in protein-deficient mice, an effect attenuated by Giardia , despite not inhibiting Lactobacillus colonization. These results highlight Giardia's potential role as a disruptor of probiotic functional activity, underscoring the imperative for further research into the complex interactions between parasites and bacteria under conditions of nutritional deficiency.

20.
JAC Antimicrob Resist ; 5(2): dlad051, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37102119

ABSTRACT

The global burden of infection from MDR organisms (MDROs) disproportionately affects children residing in low- and middle-income countries and those with increased healthcare exposure. These populations have high rates of malnutrition making them increasingly vulnerable to infection with intestinal-derived pathogens. Malnourished children experience increased incidence of intestinal carriage and invasive infection with intestinal-derived MDROs including ESBL- and carbapenemase-producing Enterobacterales. However, the relationship between malnutrition and MDRO infection remains to be clearly defined. Impairment in intestinal barrier function and innate and adaptive immunity in malnutrition increases the risk for infection with intestinal-derived pathogens, and there is an increasing appreciation of the role of the intestinal microbiota in this process. Current evidence from human studies and animal models suggests that diet and the intestinal microbiota influence each other to determine nutritional status, with important implications for infectious outcomes. These insights are crucial to developing microbiota-targeted strategies aimed at reversing the growing burden of MDRO infections in malnourished populations worldwide.

SELECTION OF CITATIONS
SEARCH DETAIL