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1.
Biofouling ; 36(3): 276-291, 2020 03.
Article in English | MEDLINE | ID: mdl-32338044

ABSTRACT

Metal release rates were measured from four different copper alloy-based materials used by the aquaculture industry: copper sheet machined into a diamond mesh, copper alloy mesh (CAM), silicon bronze welded wire mesh, and copper sheeting, and compared with conventional nylon aquaculture net treated with a cuprous oxide antifouling (AF) coating. Release rates were measured in situ in San Diego Bay using a Navy-developed Dome enclosure system at nine different time points over one year. As expected, copper was the predominant metal released, followed by zinc and nickel, which were fractional components of the materials tested. Release rates followed a temporal trend similar to those observed with copper AF coatings applied to vessel hulls: an initial spike in copper release was followed by a decline to an asymptotic low. Leachate toxicity was consistent with prior studies and was directly related to the metal concentrations, indicating the alloys tested had no additional toxicity above pure metals.


Subject(s)
Alloys/analysis , Copper/analysis , Environmental Monitoring/methods , Water Pollutants, Chemical/analysis , Alloys/chemistry , Bays/chemistry , California , Nickel/analysis , Seawater/chemistry , Zinc/analysis
2.
Rev. chil. infectol ; 34(6): 589-595, dic. 2017. graf
Article in Spanish | LILACS | ID: biblio-899764

ABSTRACT

Resumen En el siglo XIX se pensaba que la tuberculosis y la tumefacción ganglionar cervical llamada escrófula afectaban a individuos predispuestos por una "constitución diatésica" heredada. En 1882 Robert Koch demostró que lesiones tuberculosas y escrofulosas humanas eran causadas por el bacilo Mycobacterium tuberculosis. A principios del siglo XX se estableció que Mycobacterium bovis, bacilo de la tuberculosis del ganado, podía también causar linfoadenitis cervical en humanos, especialmente en niños, por la ingestión de leche de vacas enfermas. La condición disminuyó después que se controló la infección en el ganado y se introdujo la pasteurización de la leche. En 1956 se describió la linfoadenitis cervicofacial granulomatosa necrosante y supurada causada por micobacterias no tuberculosas. Afecta principalmente a niños bajo los cinco años, especialmente en países sin endemia de tuberculosis. Las linfoadenitis cervicales tuberculosas predominan en adultos jóvenes en países con tuberculosis endémica y en individuos infectados por VIH.


In the 19th century it was widely believed that both tuberculosis and cervical lymph node swelling, known as scrophula, affected individuals predisposed to an inherited "diathetic constitution". In 1882 Robert Koch proved that human tuberculosis and scrophulous lesions were caused by the bacillus Mycobacterium tuberculosis. In the early twentieth century it was stated that Mycobacterium bovis, the bacillus of cattle tuberculosis, could also cause cervical lymphoadenitis in humans, especially in children, by the intake of milk from sick cows. The incidence of this condition decreased after the infection was controlled in cattle and pasteurization of the milk was introduced. A type of granulomatous necrotizing and suppurative cervico-facial lymphadenitis associated to non-tuberculous mycobacteria was described in 1956. It mainly affects children younger than 5 years old, particularly those born in countries with non-endemic tuberculosis. Tuberculous cervical lymphadenitis is prevalent in young adults from tuberculosis-endemic countries and in HIV-infected subjects. Infectious etiology displaced the importance of a personal disposition in the development of scrophula. Nevertheless, mutations that confer susceptibility to mycobacterial infection are currently investigated.


Subject(s)
Humans , History, 19th Century , History, 20th Century , Tuberculosis, Lymph Node/history , Lymphadenitis/history , Tuberculosis, Lymph Node/microbiology , Tuberculosis, Lymph Node/pathology , Superior Cervical Ganglion/microbiology , Superior Cervical Ganglion/pathology , Lymph Nodes/microbiology , Lymph Nodes/pathology , Lymphadenitis/microbiology , Lymphadenitis/pathology , Mycobacterium/pathogenicity
3.
Ann Hepatol ; 16(5): 772-779, 2017.
Article in English | MEDLINE | ID: mdl-28809732

ABSTRACT

INTRODUCTION AND AIM: In 2008 the International autoimmune hepatitis (AIH) Group proposed the simplified diagnostic criteria for this disease. The original cohort study was performed in 11 international centers, but validation studies are scarce in Latin-America. The aim of this study is validate these criteria in Hispanic patients. MATERIAL AND METHODS: A retrospective cohort of patients undergoing percutaneous liver biopsy and follow-up of at least 12 months was recruited from a Chilean University hospital. Patients with previous immunosuppressive therapy and liver transplant recipients were excluded. The diagnostic accuracy was analyzed using as gold standard the clinical course during long-term follow-up. Sensitivity, specificity, positive and negative predictive values (PPV and NPV) and area under the ROC curve (AUROC) were calculated. RESULTS: Four hundred eighty one patients were evaluated, 294 were included. 218 (74.15%) were female, mean age 48.5 (± 12.3) years, mean follow-up 34 (± 18) months. 66 patients had AIH or overlap syndrome (22.45%), 96 (32.65%) non-alcoholic steatohepatitis, 40 (13.61%) primary biliary cholangitis, 31 (10.54%) hepatitis C, 8 (2.72%) hepatitis B, 53 (18.02%) other etiologies. The AUROC for AIH simplified criteria was 0.976. Using a cutoff ≥ 6 and ≥ 7 points, the sensitivity was 86.4% and 54.6%; specificity, 98.7% and 99.6%; PPV, 95% and 97.3%; and NPV, 96.2% and 88.6%, respectively. CONCLUSION: Simplified criteria for the diagnosis of AIH have a high accuracy in our Chilean-Hispanic cohort. The female gender is strongly associated to AIH and could help in difficult cases. Further studies with a prospective design are necessary to confirm these observations.


Subject(s)
Hepatitis, Autoimmune/diagnosis , Adolescent , Adult , Area Under Curve , Biopsy , Chile/epidemiology , Female , Hepatitis, Autoimmune/epidemiology , Hepatitis, Autoimmune/immunology , Hepatitis, Autoimmune/pathology , Humans , Male , Middle Aged , Predictive Value of Tests , ROC Curve , Reproducibility of Results , Retrospective Studies , Risk Factors , Sex Factors , Young Adult
4.
Rev Chilena Infectol ; 34(1): 55-59, 2017 Feb.
Article in Spanish | MEDLINE | ID: mdl-28394982

ABSTRACT

In the 19th century scrofula or scrofulous adenitis was a frequent condition estimated by the finding of swollen cervical lymph nodes or scars, occurring in both sexes at all epochs of life, mainly in children. It was thought that it principally affected people with an inherited phlegmatic constitution that involved a scrofulous disposition or "diathesis". The disease would be triggered by environmental agents, bad habits or excesses in style of life. Besides injuring cervical lymph nodes, in some cases scrofula could compromise other groups of lymph nodes, bones, joints, lungs or other viscera. In some of its clinical presentations the disease could be healed while others were often lethal disorders. The finding of multiorgan compromise, caseation and "tuberculization" of the lesions originated discussion whether scrofula and tuberculosis were one or two different diseases and if they affected subjects with a common diathesis or people with a distinct scrofulous or tuberculous diathesis. Along the 19th century, before the discovery of Koch's bacillus, the notion of contagion as a cause of scrofula and tuberculosis was not predominant in Europe.


Subject(s)
Tuberculosis, Lymph Node/history , History, 19th Century , Humans
5.
Rev. chil. infectol ; 34(1): 55-59, feb. 2017. ilus
Article in Spanish | LILACS | ID: biblio-844445

ABSTRACT

In the 19th century scrofula or scrofulous adenitis was a frequent condition estimated by the finding of swollen cervical lymph nodes or scars, occurring in both sexes at all epochs of life, mainly in children. It was thought that it principally affected people with an inherited phlegmatic constitution that involved a scrofulous disposition or "diathesis". The disease would be triggered by environmental agents, bad habits or excesses in style of life. Besides injuring cervical lymph nodes, in some cases scrofula could compromise other groups of lymph nodes, bones, joints, lungs or other viscera. In some of its clinical presentations the disease could be healed while others were often lethal disorders. The finding of multiorgan compromise, caseation and "tuberculization" of the lesions originated discussion whether scrofula and tuberculosis were one or two different diseases and if they affected subjects with a common diathesis or people with a distinct scrofulous or tuberculous diathesis. Along the 19th century, before the discovery of Koch's bacillus, the notion of contagion as a cause of scrofula and tuberculosis was not predominant in Europe.


En el siglo XIX la escrófula era frecuente, estimada por la percepción de nódulos o cicatrices en el cuello. Paulatinamente se le empezó a denominar adenitis escrofulosa. Podía presentarse en personas de ambos sexos en todas las épocas de la vida; pero era más frecuente en la infancia. Se pensaba que afectaba principalmente a sujetos con una constitución flemática heredada que implicaba una susceptibilidad o diátesis escrofulosa. La enfermedad sería desencadenada por agentes ambientales, hábitos, o excesos en el estilo de vida. Aparte de los ganglios linfáticos cervicales, podía afectar otros grupos ganglionares, huesos, articulaciones, pulmones y otras visceras, atribuyéndosele diversas formas de presentación que variaban entre las potencialmente curables a las frecuentemente mortales. La afectación multiorgánica, la caseificación y la "tuberculización" de las lesiones originaron la discusión sobre si la escrófula y la tuberculosis eran una sola enfermedad o dos diferentes, y si se desencadenaban sobre una diátesis común o cada una sobre una diátesis específica escrofulosa o tuberculosa. En la mayor parte del siglo XIX, antes del descubrimiento del bacilo de Koch, la noción de contagio como causa de la escrófula y de la tuberculosis pulmonar no parecía predominar en países europeos.


Subject(s)
Humans , History, 19th Century , Tuberculosis, Lymph Node/history
6.
Ann. hepatol ; 16(1): 94-106, Jan.-Feb. 2017. graf
Article in English | LILACS | ID: biblio-838091

ABSTRACT

Abstract: The use of calcineurin inhibitors (CNI) after liver transplantation is associated with post-transplant nephrotoxicity. Conversion to mycophenolate mofetil (MMF) monotherapy improves renal function, but is related to graft rejection in some recipients. Our aim was to identify variables associated with rejection after conversion to MMF monotherapy. Conversion was attempted in 40 liver transplant recipients. Clinical variables were determined and peripheral mononuclear blood cells were immunophenotyped during a 12-month follow- up. Conversion was classified as successful (SC) if rejection did not occur during the follow-up. MMF conversion was successful with 28 patients (70%) and was associated with higher glomerular filtration rates at the end of study. It also correlated with increased time elapsed since transplantation, low baseline CNI levels (Tacrolimus ≤ 6.5 ng/mL or Cyclosporine ≤ 635 ng/mL) and lower frequency of tacrolimus use. The only clinical variable independently related to SC in multivariate analysis was low baseline CNI levels (p = 0.02, OR: 6.93, 95%, CI: 1.3-29.7). Mean baseline fluorescent intensity of FOXP3+ T cells was significantly higher among recipients with SC. In conclusion, this study suggests that baseline CNI levels can be used to identify recipients with higher probability of SC to MMF monotherapy. Clinicaltrials.gov identification: NCT01321112.


Subject(s)
Humans , Male , Middle Aged , Aged , Liver Transplantation , Tacrolimus/administration & dosage , Cyclosporine/administration & dosage , Calcineurin Inhibitors/administration & dosage , Graft Rejection/prevention & control , Graft Survival/drug effects , Immunosuppressive Agents/administration & dosage , Mycophenolic Acid/administration & dosage , Time Factors , Transcription Factors/immunology , Drug Administration Schedule , T-Lymphocytes/immunology , Chi-Square Distribution , Odds Ratio , Multivariate Analysis , Prospective Studies , Risk Factors , Liver Transplantation/adverse effects , Treatment Outcome , Tacrolimus/adverse effects , Drug Monitoring/methods , Cyclosporine/adverse effects , Drug Therapy, Combination , Calcineurin Inhibitors , Graft Rejection/immunology , Immunosuppressive Agents/adverse effects , Kidney/drug effects , Kidney/physiopathology , Mycophenolic Acid/adverse effects
7.
Ann Hepatol ; 16(1): 94-106, 2017.
Article in English | MEDLINE | ID: mdl-28051798

ABSTRACT

 The use of calcineurin inhibitors (CNI) after liver transplantation is associated with post-transplant nephrotoxicity. Conversion to mycophenolate mofetil (MMF) monotherapy improves renal function, but is related to graft rejection in some recipients. Our aim was to identify variables associated with rejection after conversion to MMF monotherapy. Conversion was attempted in 40 liver transplant recipients. Clinical variables were determined and peripheral mononuclear blood cells were immunophenotyped during a 12-month follow-up. Conversion was classified as successful (SC) if rejection did not occur during the follow-up. MMF conversion was successful with 28 patients (70%) and was associated with higher glomerular filtration rates at the end of study. It also correlated with increased time elapsed since transplantation, low baseline CNI levels (Tacrolimus ≤ 6.5 ng/mL or Cyclosporine ≤ 635 ng/mL) and lower frequency of tacrolimus use. The only clinical variable independently related to SC in multivariate analysis was low baseline CNI levels (p = 0.02, OR: 6.93, 95%, CI: 1.3-29.7). Mean baseline fluorescent intensity of FOXP3+ T cells was significantly higher among recipients with SC. In conclusion, this study suggests that baseline CNI levels can be used to identify recipients with higher probability of SC to MMF monotherapy. Clinicaltrials.gov identification: NCT01321112.


Subject(s)
Calcineurin Inhibitors/administration & dosage , Cyclosporine/administration & dosage , Graft Rejection/prevention & control , Graft Survival/drug effects , Immunosuppressive Agents/administration & dosage , Liver Transplantation , Mycophenolic Acid/administration & dosage , Tacrolimus/administration & dosage , Aged , Calcineurin Inhibitors/adverse effects , Chi-Square Distribution , Cyclosporine/adverse effects , Drug Administration Schedule , Drug Monitoring/methods , Drug Therapy, Combination , Forkhead Transcription Factors/immunology , Graft Rejection/immunology , Humans , Immunosuppressive Agents/adverse effects , Kidney/drug effects , Kidney/physiopathology , Liver Transplantation/adverse effects , Male , Middle Aged , Multivariate Analysis , Mycophenolic Acid/adverse effects , Odds Ratio , Prospective Studies , Risk Factors , T-Lymphocytes/immunology , Tacrolimus/adverse effects , Time Factors , Treatment Outcome
8.
Rev Chilena Infectol ; 34(6): 589-595, 2017 Dec.
Article in Spanish | MEDLINE | ID: mdl-29488555

ABSTRACT

In the 19th century it was widely believed that both tuberculosis and cervical lymph node swelling, known as scrophula, affected individuals predisposed to an inherited "diathetic constitution". In 1882 Robert Koch proved that human tuberculosis and scrophulous lesions were caused by the bacillus Mycobacterium tuberculosis. In the early twentieth century it was stated that Mycobacterium bovis, the bacillus of cattle tuberculosis, could also cause cervical lymphoadenitis in humans, especially in children, by the intake of milk from sick cows. The incidence of this condition decreased after the infection was controlled in cattle and pasteurization of the milk was introduced. A type of granulomatous necrotizing and suppurative cervico-facial lymphadenitis associated to non-tuberculous mycobacteria was described in 1956. It mainly affects children younger than 5 years old, particularly those born in countries with non-endemic tuberculosis. Tuberculous cervical lymphadenitis is prevalent in young adults from tuberculosis-endemic countries and in HIV-infected subjects. Infectious etiology displaced the importance of a personal disposition in the development of scrophula. Nevertheless, mutations that confer susceptibility to mycobacterial infection are currently investigated.


Subject(s)
Lymphadenitis/history , Tuberculosis, Lymph Node/history , History, 19th Century , History, 20th Century , Humans , Lymph Nodes/microbiology , Lymph Nodes/pathology , Lymphadenitis/microbiology , Lymphadenitis/pathology , Mycobacterium/pathogenicity , Superior Cervical Ganglion/microbiology , Superior Cervical Ganglion/pathology , Tuberculosis, Lymph Node/microbiology , Tuberculosis, Lymph Node/pathology
9.
Rev. chil. infectol ; 33(5): 565-569, oct. 2016. ilus
Article in Spanish | LILACS | ID: biblio-1042628

ABSTRACT

This article outlines the beginning of the medical studies at the Universidad de San Felipe de Santiago de Chile on the second half of the 18th century. Dr Domingo Nevin was the first professor of Prima Medicina and Proto-medico. Dr. Pedro Manuel Chaparro was the first Chilean student who complete his studies and got his degree at the same university. Both of them had remarkable achievements during the colonial Chilean Medicine.


Se reseña el comienzo de los estudios médicos en la Universidad de San Felipe, en Santiago de Chile en la segunda mitad del siglo XVIII. El Dr. Domingo Nevin fue el primer catedrático de Prima Medicina y Protomédico. Su discípulo Dr. Pedro Manuel Chaparro fue el primer alumno chileno que completó sus estudios y se graduó en la misma Universidad. Ambos personajes tuvieron destacada trayectoria en la medicina chilena colonial.


Subject(s)
History, 18th Century , History, 19th Century , Universities/history , Education, Medical/history , Chile
10.
Rev Chilena Infectol ; 33(5): 565-569, 2016 Oct.
Article in Spanish | MEDLINE | ID: mdl-28112342

ABSTRACT

This article outlines the beginning of the medical studies at the Universidad de San Felipe de Santiago de Chile on the second half of the 18th century. Dr Domingo Nevin was the first professor of Prima Medicina and Proto-medico. Dr. Pedro Manuel Chaparro was the first Chilean student who complete his studies and got his degree at the same university. Both of them had remarkable achievements during the colonial Chilean Medicine.


Subject(s)
Education, Medical/history , Universities/history , Chile , History, 18th Century , History, 19th Century
11.
Rev Chilena Infectol ; 31(4): 459-67, 2014 Aug.
Article in Spanish | MEDLINE | ID: mdl-25327201

ABSTRACT

From the 11th century up to the beginning of the 19th century a healing rite was performed by the kings of France and England. They were considered to have a hereditary divine power to cure with their hand the scrofula, a tuberculous lymphadenitis that affects mainly cervical lymph nodes. The rite took place regularly over groups of scrofulous patients and a wide audience. The belief in that miraculous power was based on the fact that kings had been annointed and crowned in a religious ceremony, thus acquiring a priestly nature together with their temporal power. The monarchs of France and England would have stimulated their subjects' credulity to strengthen their power over the feudal lords, specially when a change of dynasty took place. Scrofula may have been chosen due to a high incidence, with an evolution that may mimick healing, and also because the concept of scrofula may have included other lesions with episodes of spontaneous remission. The available historical data and the current knowledge of tuberculous lymphadenitis do not support the belief of massive miraculous healings by the king's touch.


Subject(s)
King's Evil/history , Therapeutic Touch/history , England , France , History, 15th Century , History, 16th Century , History, 17th Century , History, 18th Century , History, 19th Century , History, Medieval , Humans
12.
Rev. méd. Chile ; 142(10): 1229-1237, oct. 2014. ilus, tab
Article in Spanish | LILACS | ID: lil-731653

ABSTRACT

Background: Preservation solutions are critical for organ transplantation. In liver transplant (LT), the solution developed by the University Of Wisconsin (UW) is the gold-standard to perfuse deceased brain death donor (DBD) grafts. Histidine-Tryptophan-Ketoglutarate (HTK), formerly a cardioplegic infusion, has been also used in solid organ transplantation. Aim: To compare the outcomes of LT in our center using either HTK or UW solution. Patients and Methods: Retrospective study including 93 LT DBD liver grafts in 89 patients transplanted between March 1994 and July 2010. Forty-eight grafts were preserved with UW and 45 with HTK. Donor and recipient demographics, total infused volume, cold ischemia time, post-reperfusion biopsy, liver function tests, incidence of biliary complications, acute rejection and 12-month graft and patient survival were assessed. Preservation solution costs per liver graft were also recorded. Results: Donor and recipient demographics were similar. When comparing UW and HTK, no differences were observed in cold ischemia time (9.6 ± 3 and 8.7 ± 2 h respectively, p = 0.23), biliary complications, the incidence of acute rejection, primary or delayed graft dysfunction. Histology on post-reperfusion biopsies revealed no differences between groups. The infused volume was significantly higher with HTK than with UW (9 (5-16) and 6 (3-11) l, p < 0.001). The cost per procurement was remarkably lower using HTK. Conclusions: Perfusion of DBD liver grafts with HTK is clinically equivalent to UW, with a significant cost reduction.


Subject(s)
Adult , Female , Humans , Male , Middle Aged , Liver , Liver Transplantation/methods , Organ Preservation Solutions , Organ Preservation/instrumentation , Adenosine , Allopurinol , Brain Death , Glucose , Glutathione , Graft Survival/drug effects , Graft Survival/physiology , Insulin , Liver Failure/pathology , Mannitol , Potassium Chloride , Procaine , Raffinose , Retrospective Studies , Tissue Donors
13.
J Pediatr Gastroenterol Nutr ; 59(6): 773-8, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25050847

ABSTRACT

OBJECTIVES: Peptic ulcer disease (PUD) is highly prevalent among adults but less common in children. Helicobacter pylori infection, the main cause of PUD, is, however, acquired extremely early in life. The aim of the study was to analyze clinical characteristics of children with PUD in a country with a high prevalence of the disease and to evaluate which host factors could determine this clinical outcome. METHODS: Children referred for upper gastrointestinal (GI) endoscopy with suspicion of peptic diseases were included prospectively during an 8-year period. Antral biopsies were performed to determine H pylori presence and mucosal cytokines profile. RESULTS: A total of 307 children between 3 and 18 years old were enrolled. Of the total, 237 children (46% boys) with complete data were included. H pylori infection was confirmed in 133 (56.1%) participants. Duodenal ulcer (DU) was diagnosed in 32 patients (13.5%); among them 29 were infected with H pylori (90.6%). Infected children had a nodular appearance of the gastric mucosa more often than noninfected children. Noninfected children had fewer lymphoid follicles and less inflammatory infiltrate than infected children. Only mucosal polymorphonuclear cell infiltration was more intense in DU-infected children as compared with non-DU-infected children. DU-infected children had higher levels of mucosal interferon-γ than noninfected and non-DU-infected patients. Non-DU-infected children had also higher levels of mucosal interleukin-10 than noninfected patients (P < 0.05). CONCLUSIONS: PUD in children, especially DU, is strongly associated with H pylori infection in developing countries. There is no distinctive clinical presentation of children with PUD. T-helper cytokine balance may influence clinical outcomes in children.


Subject(s)
Gastric Mucosa/immunology , Helicobacter Infections/immunology , Helicobacter pylori , Peptic Ulcer/immunology , Peptic Ulcer/microbiology , Adolescent , Biopsy , Child , Child, Preschool , Cytokines/analysis , Duodenal Ulcer/immunology , Duodenal Ulcer/microbiology , Female , Gastric Mucosa/microbiology , Gastric Mucosa/pathology , Helicobacter pylori/isolation & purification , Humans , Immunity, Mucosal , Male , Neutrophils/pathology
14.
Mar Pollut Bull ; 85(1): 225-34, 2014 Aug 15.
Article in English | MEDLINE | ID: mdl-24952455

ABSTRACT

The bioavailability and toxicity of copper (Cu) in Shelter Island Yacht Basin (SIYB), San Diego, CA, USA, was assessed with simultaneous toxicological, chemical, and modeling approaches. Toxicological measurements included laboratory toxicity testing with Mytilus galloprovincialis (Mediterranean mussel) embryos added to both site water (ambient) and site water spiked with multiple Cu concentrations. Chemical assessment of ambient samples included total and dissolved Cu concentrations, and Cu complexation capacity measurements. Modeling was based on chemical speciation and predictions of bioavailability and toxicity using a marine Biotic Ligand Model (BLM). Cumulatively, these methods assessed the natural buffering capacity of Cu in SIYB during singular wet and dry season sampling events. Overall, the three approaches suggested negligible bioavailability, and isolated observed or predicted toxicity, despite an observed gradient of increasing Cu concentration, both horizontally and vertically within the water body, exceeding current water quality criteria for saltwater.


Subject(s)
Copper/toxicity , Mytilus/drug effects , Water Pollutants, Chemical/analysis , Algorithms , Animals , Biological Availability , Bivalvia , California , Copper/chemistry , Islands , Ligands , Seawater/chemistry , Toxicity Tests
15.
Environ Sci Technol ; 48(14): 7730-7, 2014 Jul 15.
Article in English | MEDLINE | ID: mdl-24952958

ABSTRACT

Understanding biogeochemical cycling of trace metals in the ocean requires information about variability in metal concentrations and distribution over short, e.g., diel, time scales. Such variability and the factors that influence it are poorly characterized. To address this shortcoming, we measured trace metal concentrations in the total dissolved, colloidal, and soluble fractions every 3-4 h for several consecutive days and nights in surface waters from a coastal station. Our results show that both the concentration and the size partitioning of some biologically essential (Fe, Cu, Co, and Cd) and anthropogenic (Pb) metals are subjected to diel variations that may be related to both inorganic and biological processes (e.g., photolysis of high-molecular-weight dissolved organic matter, photoinduced reduction/oxidation of metal(hydrous)oxides, uptake by growing phytoplankton, degradation of organic matter, lysis, and grazing). The largest fluctuations were observed in the soluble and colloidal pools. Soluble Fe varied during the day-night cycle by a factor of 40, and the contribution of colloidal Pb to the total dissolved fraction increased from 6±3% during the day to as much as 70-80% during the night. Our results suggest that changes occurring over time scales of hours need to be considered when collecting and interpreting trace metal data from the surface ocean.


Subject(s)
Ecosystem , Islands , Metals/analysis , Seawater/chemistry , California , Chemical Fractionation , Colloids , Geography , Light , Phytoplankton/metabolism , Solubility , Surface Properties , Temperature
16.
Environ Sci Process Impacts ; 16(3): 501-10, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24513784

ABSTRACT

Volatile organic compounds (VOCs) are commonly associated with contaminated land and may pose a risk to human health via subsurface vapor intrusion to indoor air. Soil vapor sampling is commonly used to assess the nature and extent of VOC contamination, but can be complicated because of the wide range of geologic material permeability and moisture content conditions that might be encountered, the wide variety of available sampling and analysis methods, and several potential causes of bias and variability, including leaks of atmospheric air, adsorption-desorption interactions, inconsistent sampling protocols and varying levels of experience among sampling personnel. Passive sampling onto adsorbent materials has been available as an alternative to conventional whole-gas sample collection for decades, but relationships between the mass sorbed with time and the soil vapor concentration have not been quantitatively established and the relative merits of various commercially available passive samplers for soil vapor concentration measurement is unknown. This paper presents the results of field experiments using several different passive samplers under a wide range of conditions. The results show that properly designed and deployed quantitative passive soil vapor samplers can be used to measure soil vapor concentrations with accuracy and precision comparable to conventional active soil vapor sampling (relative concentrations within a factor of 2 and RSD comparable to active sampling) where the uptake rate is low enough to minimize starvation and the exposure duration is not excessive for weakly retained compounds.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring , Soil Pollutants/analysis , Soil/chemistry , Volatile Organic Compounds/analysis
17.
Biofouling ; 30(1): 51-68, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24199998

ABSTRACT

Copper-based epoxy and ablative antifouling painted panels were exposed in natural seawater to evaluate environmental loading parameters. In situ loading factors including initial exposure, passive leaching, and surface refreshment were measured utilizing two protocols developed by the US Navy: the dome method and the in-water hull cleaning sampling method. Cleaning techniques investigated included a soft-pile carpet and a medium duty 3M(™) pad for fouling removal. Results show that the passive leach rates of copper peaked three days after both initial deployment and cleaning events (CEs), followed by a rapid decrease over about 15 days and a slow approach to asymptotic levels on approximately day 30. Additionally, copper was more bioavailable during a CE in comparison to the passive leaching that immediately followed. A paint life cycle model quantifying annual copper loading estimates for each paint and cleaning method based on a three-year cycle of painting, episodic cleaning, and passive leaching is presented.


Subject(s)
Biofouling/prevention & control , Copper/chemistry , Paint/toxicity , Ships , Biological Availability , Copper/toxicity , Surface Properties , Water Quality
18.
Rev Med Chil ; 142(10): 1229-37, 2014 Oct.
Article in Spanish | MEDLINE | ID: mdl-25601106

ABSTRACT

BACKGROUND: Preservation solutions are critical for organ transplantation. In liver transplant (LT), the solution developed by the University Of Wisconsin (UW) is the gold-standard to perfuse deceased brain death donor (DBD) grafts. Histidine-Tryptophan-Ketoglutarate (HTK), formerly a cardioplegic infusion, has been also used in solid organ transplantation. AIM: To compare the outcomes of LT in our center using either HTK or UW solution. PATIENTS AND METHODS: Retrospective study including 93 LT DBD liver grafts in 89 patients transplanted between March 1994 and July 2010. Forty-eight grafts were preserved with UW and 45 with HTK. Donor and recipient demographics, total infused volume, cold ischemia time, post-reperfusion biopsy, liver function tests, incidence of biliary complications, acute rejection and 12-month graft and patient survival were assessed. Preservation solution costs per liver graft were also recorded. RESULTS: Donor and recipient demographics were similar. When comparing UW and HTK, no differences were observed in cold ischemia time (9.6 ± 3 and 8.7 ± 2 h respectively, p = 0.23), biliary complications, the incidence of acute rejection, primary or delayed graft dysfunction. Histology on post-reperfusion biopsies revealed no differences between groups. The infused volume was significantly higher with HTK than with UW (9 (5-16) and 6 (3-11) l, p < 0.001). The cost per procurement was remarkably lower using HTK. CONCLUSIONS: Perfusion of DBD liver grafts with HTK is clinically equivalent to UW, with a significant cost reduction.


Subject(s)
Liver Transplantation/methods , Liver , Organ Preservation Solutions , Organ Preservation/instrumentation , Adenosine , Adult , Allopurinol , Brain Death , Female , Glucose , Glutathione , Graft Survival/drug effects , Graft Survival/physiology , Humans , Insulin , Liver Failure/pathology , Male , Mannitol , Middle Aged , Potassium Chloride , Procaine , Raffinose , Retrospective Studies , Tissue Donors
19.
J Clin Pathol ; 66(4): 343-7, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23268321

ABSTRACT

AIMS: Acute Helicobacter pylori infection is associated with transient hypochlorhydria. In H pylori-associated atrophy, hypochlorhydria has a role in iron deficiency (ID) through changes in the physiology of iron-complex absorption. The aims were to evaluate the association between H pylori-associated hypochlorhydria and ID in children. METHODS: Symptomatic children (n=123) were prospectively enrolled. Blood, gastric juice and gastric biopsies were taken, respectively, for haematological analyses, pH assessment and H pylori determination, and duodenal biopsies for exclusion of coeliac disease. Stool samples were collected for parasitology/microbiology. Thirteen children were excluded following parasitology and duodenal histopathology, and five due to impaired blood analysis. RESULTS: Ten children were hypochlorhydric (pH>4) and 33 were H pylori positive. In H pylori-positive children with pH>4 (n=6) serum iron and transferrin saturation levels % were significantly lower (p<0.01) than H pylori-positive children with pH≤4. No differences in ferritin, or total iron binding capacity, were observed. In H pylori-negative children with pH>4, iron and transferrin saturation were not significantly different from children with pH≤4. CONCLUSIONS: Low serum iron and transferrin in childhood H pylori infection is associated with hypochlorhydria. In uninfected children, hypochlorhydria was not associated with altered serum iron parameters, indicating a combination of H pylori infection and/or inflammation, and hypochlorhydria has a role in the aetiology of ID. Although H pylori-associated hypochlorhydria is transient during acute gastritis, this alters iron homeostasis with clinical impact in developing countries with a high H pylori prevalence.


Subject(s)
Achlorhydria/blood , Achlorhydria/microbiology , Gastric Mucosa/metabolism , Helicobacter Infections/microbiology , Helicobacter pylori/isolation & purification , Iron Deficiencies , Stomach/microbiology , Achlorhydria/diagnosis , Adolescent , Age Factors , Biopsy , Chi-Square Distribution , Child , Endoscopy, Gastrointestinal , Feces/microbiology , Female , Gastric Acidity Determination , Gastric Juice/metabolism , Gastric Juice/microbiology , Helicobacter Infections/complications , Helicobacter Infections/diagnosis , Humans , Hydrogen-Ion Concentration , Iron/blood , Male , Predictive Value of Tests , Prospective Studies , Transferrin/analysis
20.
Ann Hepatol ; 13(1): 142-9, 2013.
Article in English | MEDLINE | ID: mdl-24378278

ABSTRACT

Hepatic involvement in primary amyloidosis is an infrequent challenge to the hepatologist. Although usually asymptomatic, amyloidosis may have unusual manifestations. Liver biopsy is an important diagnostic tool for this condition. Herein, we report three cases of portal hypertension related to primary hepatic amyloidosis, one of them in the form of acute liver failure.


Subject(s)
Amyloidosis/complications , Hypertension, Portal/etiology , Liver Failure, Acute/etiology , Aged , Amyloidosis/metabolism , Amyloidosis/pathology , Female , Humans , Immunoglobulin Light-chain Amyloidosis , Immunoglobulin kappa-Chains/metabolism , Liver/pathology , Liver Failure, Acute/metabolism , Liver Failure, Acute/pathology , Male , Middle Aged , Multiple Myeloma/complications , Multiple Myeloma/metabolism
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