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1.
Sci Robot ; 5(43)2020 06 15.
Article in English | MEDLINE | ID: mdl-33022616

ABSTRACT

Genetic control methods of mosquito vectors of malaria, dengue, yellow fever, and Zika are becoming increasingly popular due to the limitations of other techniques such as the use of insecticides. The sterile insect technique is an effective genetic control method to manage insect populations. However, it is crucial to release sterile mosquitoes by air to ensure homogeneous coverage, especially in large areas. Here, we report a fully automated adult mosquito release system operated from an uncrewed aerial vehicle or drone. Our system, developed and tested in Brazil, enabled a homogeneous dispersal of sterile male Aedes aegypti while maintaining their quality, leading to a homogeneous sterile-to-wild male ratio due to their aggregation in the same sites. Our results indicate that the released sterile males were able to compete with the wild males in mating with the wild females; thus, the sterile males were able to induce sterility in the native female population. The use of drones to implement the sterile insect technique will lead to improvements in areal coverage and savings in operational costs due to the requirement of fewer release sites and field staff.


Subject(s)
Aedes/genetics , Aedes/physiology , Aircraft/instrumentation , Mosquito Control/instrumentation , Mosquito Vectors/genetics , Mosquito Vectors/physiology , Robotics/instrumentation , Animals , Brazil , Computer Simulation , Equipment Design , Female , Humans , Infertility, Male , Male , Mosquito Control/methods , Mosquito Control/statistics & numerical data , Robotics/statistics & numerical data , Software , Vector Borne Diseases/prevention & control , Vector Borne Diseases/transmission
2.
Appl Radiat Isot ; 134: 470-476, 2018 Apr.
Article in English | MEDLINE | ID: mdl-28838724

ABSTRACT

A methodology including software tools for analysing NORM building materials and residues by low-level gamma-ray spectrometry has been developed. It comprises deconvolution of gamma-ray spectra using the software GALEA with focus on the natural radionuclides and Monte Carlo simulations for efficiency and true coincidence summing corrections. The methodology has been tested on a range of building materials and validated against reference materials.

3.
Parasite Immunol ; 32(3): 202-8, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20398183

ABSTRACT

Chagas heart disease (CHD), caused by Trypanosoma cruzi infection, is a significant cause of morbidity and mortality in South and Central America. Enalapril, an angiotensin converting enzyme (ACE) inhibitor, is an important drug used to ameliorate heart functional capacity and its remodelling in individuals presenting CHD. In this study, we evaluated the effects of enalapril on systemic and cardiac immune response during experimental acute CHD. C57BL/6 mice infected with 50 trypomastigote forms of T. cruzi (Colombian strain) were treated daily with enalapril (25 mg/kg) and, after 30 days, a reduction in seric levels of IFN-gamma, TNF-alpha, CCL5/RANTES and nitric oxide, but not in that of IL-10, was detected. This imbalance of cytokines reflects in a reduction of heart mononuclear infiltration and in an increasing of cardiac mast cells. Enalapril also presents a new and interesting in vitro and in vivo anti-T. cruzi activity probably acting on parasite oxidative pathway via cytochrome-P450. Our data show that enalapril exerts an important anti-T. cruzi and anti-inflammatory activity during acute CHD reducing inflammatory cells and, possibly, preventing fibrotic process in the chronic phase. Nevertheless, further studies are still necessary to clarify the mechanisms by which this drug is acting on the parasites and on the immune pathways.


Subject(s)
Antiprotozoal Agents/administration & dosage , Chagas Cardiomyopathy/prevention & control , Chagas Disease/complications , Chagas Disease/drug therapy , Enalapril/administration & dosage , Trypanosoma cruzi/drug effects , Animals , Chagas Disease/immunology , Chagas Disease/pathology , Cytokines/blood , Male , Mice , Mice, Inbred C57BL , Nitric Oxide/blood , Serum/chemistry
5.
J Viral Hepat ; 13(4): 242-9, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16611190

ABSTRACT

In previous hepatitis C virus (HCV) treatment studies, Black patients not only had a lower sustained viral response (SVR) rate to interferon and ribavirin (RBV) than non-Black patients but also a higher frequency of HCV genotype 1 (GT-1) infection. The aim of this community-based study was to determine whether Black patients have a lower SVR rate independent of genotype. We prospectively enrolled 785 patients (24.8% Black, 71.5% White, 3.7% others) who received interferon alpha-2b 3 MU three times weekly + RBV 1000-1200 mg/day for 24 weeks (GT-2/3) or 48 weeks (GT-1). Black patients were more commonly infected with GT-1 (86.8%vs 64.8%, P < 0.001) and less frequently had an SVR compared with non-Black patients (8.4%vs 21.6%, P < 0.001). Within GT-1, Black patients had a lower SVR rate than non-Black patients (6.1%vs 14.1%, P = 0.004) but not within GT-2/3 (50.0%vs 36.5%, P = 0.47). Black patients had lower baseline haemoglobin levels (14.8 vs 15.3 g/dL, P < 0.001) and neutrophil counts (2900 vs 4100/mm(3), P < 0.001) and required more frequent dose reductions of RBV (29.8%vs 18.5%, P < 0.001) and interferon (4.7%vs 1.6%, P = 0.012). However, dose reductions were not associated with lower SVR rates while early treatment discontinuations were (2.9%vs 25.7%, P < 0.001). Independent predictors of SVR were GT-1 [odds ratio (OR) 0.33; 95% confidence interval (CI) 0.20-0.55; P < 0.001], Black race (OR 0.45; 95% CI 0.22-0.93; P = 0.030), and advanced fibrosis, stages 3 + 4 (OR 0.53; 95% CI 0.31-0.92; P = 0.023). In conclusion, Black patients infected with HCV GT-1 (but not GT-2/3) have a lower SVR rate than non-Black patients. This is not explained by their lower baseline haemoglobin levels and neutrophil counts that lead to higher rates of ribavirin and interferon dose reductions.


Subject(s)
Antiviral Agents/administration & dosage , Black People , Hepacivirus/genetics , Hepatitis C, Chronic/drug therapy , Interferon-alpha/administration & dosage , Ribavirin/administration & dosage , Alanine Transaminase/blood , Antiviral Agents/adverse effects , Biopsy , Dose-Response Relationship, Drug , Female , Genotype , Hepatitis C, Chronic/blood , Hepatitis C, Chronic/virology , Humans , Interferon-alpha/adverse effects , Liver Cirrhosis/pathology , Logistic Models , Male , Middle Aged , Multivariate Analysis , Prospective Studies , RNA, Viral/blood , Ribavirin/adverse effects , White People
6.
Arch Intern Med ; 160(6): 844-52, 2000 Mar 27.
Article in English | MEDLINE | ID: mdl-10737285

ABSTRACT

BACKGROUND: Chest pain is a common clinical problem, but up to 30% of patients who present with chest pain lack coronary disease. Subsequent investigation often reveals an esophageal source for the pain, with gastroesophageal reflux disease identified most frequently. Controversy exists regarding whether to establish the cause or to empirically treat as reflux. OBJECTIVE: To assess the cost-effectiveness of empirical treatment in patients with noncardiac chest pain. METHODS: Decision analysis was used to compare a strategy of empirical treatment as reflux using an H-blocker or proton pump inhibitor with initial investigation for gastrointestinal causes over a period of up to 16 weeks and over a period of more than a year. The prototype patient was an outpatient with chest pain and a normal coronary angiogram. Gastrointestinal investigations included an upper gastrointestinal tract series, endoscopy, manometry, 24-hour pH monitoring, and provocation tests. The main outcome measure was direct medical costs per case treated from a third-party payer perspective. RESULTS: Total medical costs were $2,187 per case treated for the initial investigation arm and $849 for the empirical treatment arm in the 8- to 16-week model. One-way sensitivity analyses revealed that the model was robust; the treatment arm was less expensive in all cases. At just over a year empirical treatment remained dominant. CONCLUSIONS: An initial therapeutic trial with antisecretory agents for patients with noncardiac chest pain is cost-effective compared with investigation for gastrointestinal causes in the short term of weeks, with cost savings persisting beyond a year.


Subject(s)
Chest Pain/economics , Chest Pain/therapy , Gastroesophageal Reflux/diagnosis , Gastroesophageal Reflux/economics , Health Care Costs , Adult , Aged , Chest Pain/diagnostic imaging , Chest Pain/etiology , Coronary Disease/diagnosis , Coronary Disease/economics , Cost-Benefit Analysis , Decision Support Techniques , Decision Trees , Diagnosis, Differential , Female , Gastroesophageal Reflux/complications , Gastroesophageal Reflux/diagnostic imaging , Humans , Male , Middle Aged , Radiography , Sensitivity and Specificity , United States
7.
JAMA ; 277(17): 1380-6, 1997 May 07.
Article in English | MEDLINE | ID: mdl-9134944

ABSTRACT

OBJECTIVE: To determine whether long-term supplementation with vitamin E enhances in vivo, clinically relevant measures of cell-mediated immunity in healthy elderly subjects. DESIGN: Randomized, double-blind, placebo-controlled intervention study. SETTING AND PARTICIPANTS: A total of 88 free-living, healthy subjects at least 65 years of age. INTERVENTION: Subjects were randomly assigned to a placebo group or to groups consuming 60, 200, or 800 mg/d of vitamin E for 235 days. MAIN OUTCOME MEASURES: Delayed-type hypersensitivity skin response (DTH); antibody response to hepatitis B, tetanus and diphtheria, and pneumococcal vaccines; and autoantibodies to DNA and thyroglobulin were assessed before and after supplementation. RESULTS: Supplementation with vitamin E for 4 months improved certain clinically relevant indexes of cell-mediated immunity in healthy elderly. Subjects consuming 200 mg/d of vitamin E had a 65% increase in DTH and a 6-fold increase in antibody titer to hepatitis B compared with placebo (17% and 3-fold, respectively), 60-mg/d (41% and 3-fold, respectively), and 800-mg/d (49% and 2.5-fold, respectively) groups. The 200-mg/d group also had a significant increase in antibody titer to tetanus vaccine. Subjects in the upper tertile of serum alpha-tocopherol (vitamin E) concentration (>48.4 micromol/L [2.08 mg/dL]) after supplementation had higher antibody response to hepatitis B and DTH. Vitamin E supplementation had no effect on antibody titer to diphtheria and did not affect immunoglobulin levels or levels of T and B cells. No significant effect of vitamin E supplementation on autoantibody levels was observed. CONCLUSIONS: Our results indicate that a level of vitamin E greater than currently recommended enhances certain clinically relevant in vivo indexes of T-cell-mediated function in healthy elderly persons. No adverse effects were observed with vitamin E supplementation.


Subject(s)
Immunity, Cellular/drug effects , Vitamin E/pharmacology , Aged , Analysis of Variance , Autoantibodies/analysis , Cytotoxicity, Immunologic , Double-Blind Method , Female , Food, Fortified , Health Status , Humans , Hypersensitivity, Delayed/immunology , Immunoglobulins/analysis , Male , Vaccination , Vitamin E/administration & dosage
8.
Scand J Gastroenterol ; 31(7): 671-7, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8819216

ABSTRACT

BACKGROUND: Oral ethanol intake results in lower blood ethanol concentrations than intravenous administration of the same dose of ethanol. This first-pass metabolism is thought to be due to gastric metabolism of ethanol via alcohol dehydrogenase and also to hepatic first-pass metabolism. METHODS: Since a loss of gastric mucosa may decrease first-pass metabolism of ethanol, this metabolism was studied in 10 elderly subjects (6 women and 4 men) with atrophic gastritis and bacterial overgrowth and in 17 control subjects with normal gastric secretory function. Atrophic gastritis was verified by means of the serum pepsinogen I to pepsinogen II ratio and the hypochlorhydria occurring after pentagastrin stimulation. Bacterial overgrowth was assessed by bacteria. In addition, gastric emptying rates of ethanol solution with technetium-99m sulfur colloid were calculated from scintigraphic images. Furthermore, gastric biopsy specimens were taken from 12 female patients with atrophic gastritis and from 12 controls for determination of alcohol dehydrogenase activity. RESULTS: Neither gender (female versus male, 28 +/- 5% versus 42 +/- 5%), atrophic gastritis (normal versus atrophic gastritis, 35 +/- 4% versus 32 +/- 6%), nor tetracycline treatment in atrophic gastritis subjects (before versus after, 32 +/- 6% versus 41 +/- 5%) had a statistically significant effect on the first-pass metabolism of ethanol in the elderly. Gastric alcohol dehydrogenase activity was significantly lower in atrophic gastritis subjects than in controls (p < 0.01). A significant correlation was found between the first-pass metabolism of ethanol in healthy controls and gastric half-emptying time (p = 0.032). CONCLUSIONS: We conclude from these data that the rate of gastric emptying modulates first-pass metabolism of ethanol in elderly individuals.


Subject(s)
Ethanol/metabolism , Gastric Emptying/physiology , Gastritis, Atrophic/physiopathology , Aged , Aged, 80 and over , Alcohol Dehydrogenase/metabolism , Female , Gastric Juice/microbiology , Gastric Mucosa/enzymology , Humans , Male , Pepsinogens/blood , Tetracycline/pharmacology
9.
Clin Transplant ; 9(4): 322-5, 1995 Aug.
Article in English | MEDLINE | ID: mdl-7579741

ABSTRACT

Glucocorticoids have been an important part of maintenance immunosuppressive therapy following orthotopic liver transplantation (OLT). However, long-term daily glucocorticoid use is associated with a high incidence of unpleasant side effects. In an effort to minimize side effects while maintaining adequate immunosuppression, we have treated 48 adult patients with low dose alternate-day prednisone, 15 mg q.o.d. Pre-OLT diagnoses included primary biliary cirrhosis (16 patients), alcoholic liver disease (8 patients), sclerosing cholangitis (8 patients), cryptogenic cirrhosis and/or non-A, non-B hepatitis (11 patients), acute hepatic failure (3 patients), and hepatocellular carcinoma and bile duct carcinoma (1 patient each). Conversion to alternate-day prednisone was attempted when patients were clinically stable and the daily prednisone dose was 15 mg. The average interval between OLT and beginning of the conversion to alternate-day prednisone was 38 weeks. The mean time for conversion to alternate-day prednisone was 35 weeks, but decreased as more experience was gained. The mean follow-up was 106 weeks. Cushingoid side effects diminished in all. In 47 of the 48 patients, there were no clinical laboratory or histologic changes suggestive of rejection after the initiation of alternate-day prednisone. A single episode of rejection occurred during the taper. This episode responded promptly to increased glucocorticoid therapy, and the patient was easily converted to alternate-day prednisone at a later date. There was no increase in concurrent immunosuppressives dosage after the conversion. Alternate-day prednisone is effective and safe for chronic immunosuppression after OLT in patients receiving cyclosporine and azathioprine.


Subject(s)
Glucocorticoids/therapeutic use , Immunosuppressive Agents/therapeutic use , Liver Transplantation , Prednisone/therapeutic use , Adolescent , Adult , Aged , Azathioprine/therapeutic use , Bile Duct Neoplasms/surgery , Carcinoma, Hepatocellular/surgery , Cholangiocarcinoma/surgery , Cholangitis, Sclerosing/surgery , Cushing Syndrome/prevention & control , Cyclosporine/therapeutic use , Drug Administration Schedule , Female , Follow-Up Studies , Glucocorticoids/administration & dosage , Glucocorticoids/adverse effects , Graft Rejection/etiology , Hepatitis, Viral, Human/surgery , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/adverse effects , Incidence , Liver Cirrhosis/surgery , Liver Cirrhosis, Biliary/surgery , Liver Diseases, Alcoholic/surgery , Liver Failure, Acute/surgery , Liver Neoplasms/surgery , Male , Middle Aged , Prednisone/administration & dosage , Prednisone/adverse effects
10.
Abdom Imaging ; 20(4): 353-6, 1995.
Article in English | MEDLINE | ID: mdl-7549742

ABSTRACT

Magnetic resonance cholangiography (MRC) can be performed with data from a routine imaging protocol, without the need for additional pulse sequences or special equipment. We studied three patients with obstructive jaundice who underwent magnetic resonance imaging (MRI) of the liver. T2-weighted fat suppressed fast spin-echo sequences were processed with a maximum intensity projection algorithm to create three-dimensional images of the dilated portions of the biliary tree. Results were correlated with endoscopic retrograde cholangiopancreatography and computed tomography. These images compared favorably with those acquired on scanners in which special breath-holding gradient echo protocols are used.


Subject(s)
Bile Ducts/pathology , Cholestasis/diagnosis , Magnetic Resonance Imaging , Aged , Algorithms , Cholangiocarcinoma/diagnosis , Cholangiocarcinoma/diagnostic imaging , Cholangiography , Cholangiopancreatography, Endoscopic Retrograde , Cholestasis/diagnostic imaging , Common Bile Duct Diseases/diagnosis , Common Bile Duct Diseases/diagnostic imaging , Common Bile Duct Neoplasms/diagnosis , Common Bile Duct Neoplasms/diagnostic imaging , Humans , Image Enhancement/methods , Liver/pathology , Magnetic Resonance Imaging/methods , Male , Middle Aged , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/diagnostic imaging , Tomography, X-Ray Computed
11.
Am J Clin Nutr ; 61(2): 353-9, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7840074

ABSTRACT

The effect of the live bacterial yogurt cultures, namely Streptococcus thermophilus and Lactobacillus bulgaricus, and a mucosal adhering strain of Lactobacillus gasseri (ADH) on small intestinal and fecal bacterial characteristics was examined in 10 elderly subjects with atrophic gastritis and 23 elderly normal volunteers (11 received yogurt and 12 received ADH). Neither S thermophilus nor L bulgaricus was recovered from the stomach or small intestine of subjects fed yogurt or pasteurized yogurt. ADH was recovered from gastric or small intestinal aspirates in three of four subjects and in the stools of four of five subjects diagnosed with atrophic gastritis. In 11 of 12 normal subjects, ADH was isolated from stools. There was a significant reduction in fecal bacterial enzyme activity in both normal volunteers and subjects with atrophic gastritis after being fed with viable ADH. Adherent strains of bacteria such as ADH are likely to survive passage through the gastrointestinal tract and thus have greater metabolic effects.


Subject(s)
Gastritis, Atrophic/microbiology , Lactobacillus/enzymology , Yogurt/microbiology , Aged , Aged, 80 and over , Diet , Feces/enzymology , Glucuronidase/metabolism , Humans , Hydrogen-Ion Concentration , Jejunum/microbiology , Middle Aged , NADH, NADPH Oxidoreductases/metabolism , Nitroreductases/metabolism
12.
J Am Coll Nutr ; 13(6): 584-91, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7706591

ABSTRACT

OBJECTIVE: To investigate the effects of hypochlorhydria and acidic drink ingestion on protein-bound vitamin B12 absorption in elderly subjects. METHODS: Absorption of protein-bound vitamin B12 was examined in elderly normal subjects (n = 8), and in hypochlorhydric subjects due to omeprazole treatment (n = 8) or with atrophic gastritis (n = 3). Subjects underwent absorption tests of protein-bound vitamin B12 ingested with water, cranberry juice and 0.1 N hydrochloric acid. RESULTS: Protein-bound vitamin B12 absorption was lower in the omeprazole-treated group (0.50%) compared to the normal group (1.21%; p < 0.001). With cranberry juice ingestion, the omeprazole-treated group showed an increase in absorbed protein-bound vitamin B12 (p = 0.025). With dilute hydrochloric acid ingestion, there was a further increase in vitamin B12 absorption (p < 0.001). CONCLUSION: Omeprazole causes protein-bound vitamin B12 malabsorption, and ingestion of an acidic drink improves protein-bound vitamin B12 absorption.


Subject(s)
Achlorhydria/chemically induced , Achlorhydria/etiology , Gastritis, Atrophic/complications , Omeprazole/adverse effects , Vitamin B 12/pharmacokinetics , Absorption , Achlorhydria/physiopathology , Administration, Oral , Aged , Aged, 80 and over , Female , Gastric Acid/metabolism , Gastric Acidity Determination , Gastritis, Atrophic/physiopathology , Humans , Hydrochloric Acid/administration & dosage , Hydrochloric Acid/pharmacology , Hydrogen-Ion Concentration , Male , Omeprazole/therapeutic use , Pepsinogens/blood , Protein Binding , Radioimmunoassay
13.
Gastroenterology ; 106(3): 615-23, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8119531

ABSTRACT

BACKGROUND/AIMS: Bacterial overgrowth of the small intestine commonly occurs in association with hypochlorhydria caused by atrophic gastritis or during treatment with omeprazole. The purpose of this study was to determine the clinical significance of bacterial overgrowth on small intestinal absorption and permeability and to evaluate the reliability of noninvasive breath tests to detect bacterial overgrowth in subjects with hypochlorhydria. METHODS: Seventeen healthy, elderly subjects with atrophic gastritis or omeprazole treatment (40 mg/day) and documented bacterial overgrowth were studied. RESULTS: There was no evidence of fat malabsorption (72-hour fecal fat) or clinically significant carbohydrate malabsorption (25 g D-xylose and fecal pH) in any subject. The ratio of lactulose to mannitol excreted was normal in both atrophic gastritis and omeprazole-treated groups. Three subjects in each group had abnormally high alpha 1-antitrypsin clearances. Lactulose (10 g) and glucose (80 g) hydrogen breath tests were only abnormal in 1 out of 17 subjects, whereas the 1 g [14C]D-xylose test was abnormal in 6 out of 17 subjects. CONCLUSIONS: Bacterial overgrowth caused by atrophic gastritis or omeprazole treatment is typically not associated with clinically significant fat or carbohydrate malabsorption. Noninvasive breath tests for bacterial overgrowth are not reliable in subjects with hypochlorhydria.


Subject(s)
Achlorhydria/metabolism , Achlorhydria/microbiology , Bacteria/growth & development , Intestinal Absorption , Aged , Carbohydrates/pharmacokinetics , Colony-Forming Units Assay , Fats/analysis , Fats/pharmacokinetics , Feces/chemistry , Female , Gastritis/metabolism , Gastritis/microbiology , Humans , Lactulose/urine , Male , Mannitol/urine , Middle Aged , Omeprazole/adverse effects , Vitamin B 12/blood , Xylose/urine
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