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1.
Small ; : e2309127, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38554016

ABSTRACT

Conventional separation technologies for valuable commodities require substantial energy, accounting for 10%-15% of global consumption. Mixed-matrix membranes (MMMs) offer a promising solution by combining processable polymers with selective inorganic fillers. Here, the potential of using ordered microporous structured materials is demonstrated as MMM fillers. The use of ordered macroporous ZIF-67 in combination with the well-known 6FDA-DAM polymer leads to superior performance in the important separation of propylene from propane. The enhanced performance can be rationalized with the help of advanced microscopy, which demonstrates that the polymer is able to penetrate the macroporous network around which the MOF (Metal-Organic Framework) is synthesized, resulting in a much better interphase between the two components and the homogeneous distribution of the filler, even at high loadings.

2.
Article in English | MEDLINE | ID: mdl-38079363

ABSTRACT

The selective hydrogenation of aldehydes and olefins plays a crucial role in the synthesis of various industrial products. Immobilizing noble metal catalysts on solid supports has been pursued to overcome the challenges associated with catalyst separation and recovery. In this study, we explore the use of metal-organic frameworks (MOFs) as supports for the immobilization of molecular ruthenium catalysts in the hydrogenation of olefins and aldehydes. We designed a mixed-linker MOF by incorporating the picolylamine moiety, which is a ligand known for its excellent catalytic activity. The ruthenium catalysts were prepared via a simple metal-ligand coordination process without the need for additional treatments. The resulting catalysts exhibit high catalytic activity and a uniform distribution of ruthenium sites on the MOF crystals. The choice of ruthenium precursor has a significant influence on the catalytic performance, with even lower metal content resulting in higher activity. The catalysts achieve high conversion rates and selectivities in the hydrogenation of various olefins. However, in the hydrogenation of aldehydes, due to the harsher conditions required, the formation of small nanoparticles is observed after the reaction. Overall, our findings highlight the potential of picolylamine-modified MOFs as effective supports for the development of highly active heterogeneous catalysts for selective hydrogenation reactions.

3.
Toxicon X ; 17: 100148, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36593898

ABSTRACT

Peroxisomicine A1 (PA1) is a toxin isolated from the Karwinskia genus plants whose target organs are the liver, kidney, and lung. In vitro studies demonstrated the induction of apoptosis by PA1 in cancer cell lines, and in vivo in the liver. Apoptosis has a wide range of morphological features such as cell shrinkage, plasma membrane blistering, loss of microvilli, cytoplasm, and chromatin condensation, internucleosomal DNA fragmentation, and formation of apoptotic bodies that are phagocytized by resident macrophages or nearby cells. Early stages of apoptosis can be detected by mitochondrial alterations. We investigated the presence of apoptosis in vivo at the morphological, ultrastructural, and biochemical levels in two target organs of PA1: kidney and lung. Sixty CD-1 mice were divided into three groups (n = 20): untreated control (ST), vehicle control (VH), and PA1 intoxicated group (2LD50). Five animals of each group were sacrificed at 4, 8, 12, and 24 h post-intoxication. Kidney and lung were examined by morphometry, histopathology, ultrastructural, and DNA fragmentation analysis. Pre-apoptotic mitochondrial alterations were present at 4 h. Apoptotic bodies were observed at 8 h and increased over time. TUNEL positive cells were detected as early as 4 h, and the DNA ladder pattern was observed at 12 h and 24 h. The liver showed the highest value of fragmented DNA, followed by the kidney and the lung. We demonstrated the induction of apoptosis by a toxic dose of PA1 in the kidney and lung in vivo. These results could be useful in understanding the mechanism of action of this compound at toxic doses in vivo.

4.
Atmos Chem Phys ; 24(8): 4949-4972, 2023 Oct 06.
Article in English | MEDLINE | ID: mdl-38846712

ABSTRACT

The design of emission abatement measures to effectively reduce high ground-level ozone (O3) concentrations in urban areas is very complex. In addition to the strongly non-linear chemistry of this secondary pollutant, precursors can be released by a variety of sources in different regions, and locally produced O3 is mixed with that transported from the regional or continental scales. All of these processes depend also on the specific meteorological conditions and topography of the study area. Consequently, high-resolution comprehensive modeling tools are needed to understand the drivers of photochemical pollution and to assess the potential of local strategies to reduce adverse impacts from high tropospheric O3 levels. In this study, we apply the Integrated Source Apportionment Method (ISAM) implemented in the Community Multiscale Air Quality (CMAQ v5.3.2) model to investigate the origin of summertime O3 in the Madrid region (Spain). Consistent with previous studies, our results confirm that O3 levels are dominated by non-local contributions, representing around 70 % of mean values across the region. Nonetheless, precursors emitted by local sources, mainly road traffic, play a more important role during O3 peaks, with contributions as high as 25 ppb. The potential impact of local measures is higher under unfavorable meteorological conditions associated with regional accumulation patterns. These findings suggest that this modeling system may be used in the future to simulate the potential outcomes of specific emission abatement measures to prevent high-O3 episodes in the Madrid metropolitan area.

5.
Animals (Basel) ; 12(19)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36230270

ABSTRACT

The effect of short- and long-term exposure to heat stress (HS) was analyzed on blood components, performance, and intestinal epithelium integrity of pigs. Eighteen pigs (36.0 ± 3.5 kg BW) were assigned to three groups: thermo-neutral (TN); 2 d exposure to HS (2dHS); and 7 d exposure to HS (7dHS). Blood chemistry and hemogram analyses were performed; small intestine samples were analyzed for mRNA expression and histology. Compared to TN, 2dHS and 7dHS pigs reduced weight gain and feed intake; weight gain was higher in 7dHS than in 2dHS pigs (p < 0.05). White blood cells, platelet, and hematocrit were affected in 2dHS and 7dHS compared to TN pigs (p < 0.05). Short- and long-term exposure to HS affected blood concentration of triglycerides, urea, total protein, and albumin (p ≤ 0.05). Villi-height and crypt-depth decreased in HS pigs (p < 0.01). Mucin-producing and apoptotic cell number increased in 7dHS compared to TN pigs (p < 0.05). Expression of tight-junction-proteins decreased in 2dHS pigs compared to TN and 7dHS pigs (p < 0.05). Short-term exposure of pigs to HS dramatically affects performance, blood components, and integrity of the small intestine epithelia; nevertheless, pigs show signs of recovery at 7 d of HS exposure.

6.
Vet Immunol Immunopathol ; 252: 110481, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36037670

ABSTRACT

Encephalitozoon cuniculi spores cause severe granulomatous inflammation in the brain where mononuclear cells and macrophages infiltrate. Here, we orally infected New Zealand white rabbits with 1 × 106E. cuniculi viable spores to study the recruitment and localization of macrophages in brain granulomas. At day 30 post-infection, the positive phenotype markers iNOS (M1) and Arg-1 (M2) were located in the periphery and center of granulomas, respectively. Live intracytoplasmic spores were found only in positive Arg-1 cells. This is the first work to describe the recruitment and distribution of M1 and M2 macrophages in the brain granulomas of rabbits infected with E. cuniculi.


Subject(s)
Encephalitozoon cuniculi , Encephalitozoonosis , Animals , Brain , Encephalitozoonosis/veterinary , Granuloma/veterinary , Macrophages , Rabbits
7.
J Comp Pathol ; 189: 72-76, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34886988

ABSTRACT

Mixed pneumoconiosis is a pulmonary disease associated with several inhaled mineral irritants. Dust was found in the alveolar macrophages, alveolar and bronchial walls and pulmonary interstitial tissue of two female coyotes (Canis latrans). The dust contained large amounts of silica, coal, iron and copper particles, which were associated with severe pulmonary disease. Lung injury in the animals was characterized by pulmonary nodules, severe interstitial fibrosis, alveolar hyperplasia and bone formation within alveolar spaces. Coyotes inhaled mineral dust while roaming a field close to three mineral extraction zones. To our knowledge, this is the first report of the concomitant inhalation of multiple minerals in association with diffuse pulmonary ossification in the pulmonary parenchyma of two wild canine animals.


Subject(s)
Coyotes , Dog Diseases , Pneumoconiosis , Animals , Dogs , Dust , Female , Lung , Osteogenesis , Pneumoconiosis/veterinary
8.
Medicina (Kaunas) ; 57(11)2021 Oct 20.
Article in English | MEDLINE | ID: mdl-34833355

ABSTRACT

Background and Objectives: Nutritional deficiencies are one of the main triggers for the development of gastrointestinal diseases, such as ulcerative colitis (UC). Therefore, the objective of the present work consisted of determining the nutrients present in the bone broth (BB) and evaluating their anti-inflammatory properties in a murine model of UC, induced by intrarectal administration of 2, 4, 6-trinitrobenzene sulfonic acid (TNBS), and acetic acid (AcOH). The BB was prepared from the femur of bovine cattle and cooked in distilled water for 8 h at 100 ± 2 °C. Materials and Methods: The BB was administered ad libitum to BALB/c mice for 10 days before the induction of UC. Colon samples were collected for histological analysis and determination of cytokine expression levels by qPCR. Results: It was found that amino acids (AA) are the main nutritional contribution of BB, 54.56% of these correspond to essential AA. The prophylactic administration of BB in the murine model of UC reduced histological damage, decreased the expression of IL-1ß (61.12%), IL-6 (94.70%), and TNF-α (68.88%), and increased the expression of INF-γ (177.06%), IL-4 (541.36%), and IL-10 (531.97%). Conclusions: This study shows that BB has anti-inflammatory properties, and its consumption can decrease the symptoms of UC.


Subject(s)
Colitis, Ulcerative/etiology , Colitis, Ulcerative/therapy , Malnutrition/complications , Nutrients/therapeutic use , Animals , Anti-Inflammatory Agents/therapeutic use , Cattle , Cytokines , Disease Models, Animal , Mice , Mice, Inbred BALB C , Trinitrobenzenesulfonic Acid/therapeutic use
9.
Angew Chem Int Ed Engl ; 60(51): 26476-26482, 2021 Dec 13.
Article in English | MEDLINE | ID: mdl-34648675

ABSTRACT

We report the synthesis of a highly active and stable metal-organic framework derived Ni-based catalyst for the photothermal reduction of CO2 to CH4 . Through the controlled pyrolysis of MOF-74 (Ni), the nature of the carbonaceous species and therefore photothermal performance can be tuned. CH4 production rates of 488 mmol g-1 h-1 under UV-visible-IR irradiation are achieved when the catalyst is prepared under optimized conditions. No particle aggregation or significant loss of activity were observed after ten consecutive reaction cycles or more than 12 hours under continuous flow configuration. Finally, as a proof-of-concept, we performed an outdoor experiment under ambient solar irradiation, demonstrating the potential of our catalyst to reduce CO2 to CH4 using only solar energy.

10.
PeerJ ; 9: e11108, 2021.
Article in English | MEDLINE | ID: mdl-33976962

ABSTRACT

BACKGROUND: This study describes the occurrence of antimicrobial resistance (AMR) in commensal Escherichia coli and Enterococcus/Streptococcus spp. (ES) isolated from fecal samples of dairy cows and assesses the variation of AMR profiles across regions and seasons following the implementation of the Food and Agricultural Code (FAC) Sections 14400-14408 (formerly known as Senate Bill, SB 27) in California (CA). METHODS: The study was conducted on ten dairies distributed across CA's three milk sheds: Northern California (NCA), Northern San Joaquin Valley (NSJV), and the Greater Southern California (GSCA). On each study dairy, individual fecal samples were collected from two cohorts of lactating dairy cows during the fall/winter 2018 and spring/summer 2019 seasons. Each cohort comprised of 12 cows per dairy. The fecal samples were collected at enrollment before calving (close-up stage) and then monthly thereafter for four consecutive time points up to 120 days in milk. A total of 2,171 E. coli and 2,158 ES isolates were tested for antimicrobial susceptibility using the broth microdilution method against a select panel of antimicrobials. RESULTS: The E. coli isolates showed high resistance to florfenicol (83.31% ± 0.80) and sulphadimethoxine (32.45%), while resistance to ampicillin (1.10% ± 0.21), ceftiofur (1.93% ± 0.29), danofloxacin (4.01% ± 0.42), enrofloxacin (3.31% ± 0.38), gentamicin (0.32% ± 0.12) and neomycin (1.61% ± 0.27) had low resistance proportions. The ES isolates were highly resistant to tildipirosin (50.18% ± 1.10), tilmicosin (48% ± 1.10), tiamulin (42%) and florfenicol (46% ± 1.10), but were minimally resistant to ampicillin (0.23%) and penicillin (0.20%). Multidrug resistance (MDR) (resistance to at least 1 drug in ≥3 antimicrobial classes) was observed in 14.14% of E. coli isolates and 39% of ES isolates. Escherichia coli isolates recovered during winter showed higher MDR prevalence compared to summer isolates (20.33% vs. 8.04%). A higher prevalence of MDR was observed in NSJV (17.29%) and GSCA (15.34%) compared with NCA (10.10%). CONCLUSIONS: Our findings showed high rates of AMR to several drugs that are not labeled for use in lactating dairy cattle 20 months of age or older. Conversely, very low resistance was observed for drugs labeled for use in adult dairy cows, such as cephalosporins and penicillin. Overall, our findings identified important differences in AMR by antimicrobial class, region and season.

11.
Poult Sci ; 100(2): 738-745, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33518127

ABSTRACT

The addition prebiotics in broiler diets can benefit digestion and nutrient abortion. The objective of the present study was to evaluate the effects of moringa leaf powder and agave inulin on growth performance, intestinal morphology, and slaughter traits of broiler chickens over 40 d of grow-out. A total of 280 broilers (Ross 308) aged 1 d were randomly allocated to 4 treatments, with 7 replicates each and 10 chicks per replicate: T1 = control diet, T2 = control diet with 15 g/kg of moringa leaf powder, T3 = control diet with 15 g/kg of agave inulin, and T4 = control diet with 15 g/kg of moringa leaf powder and 15 g/kg of agave inulin. The results showed that analysis of treatments at time were not different (P > 0.05) for broiler weights, feed and water intake, and weight gain. Treatment was significant (P < 0.05) for feed efficiency at 22 to 40 d; the T4 group presented higher (P < 0.05) values, and the T1 group presented lower (P < 0.05) values. However, the villus lengths of intestinal sections were different (P < 0.05) among treatments. In the duodenum, jejunum, and ileum, villus lengths were highest (P < 0.05) in the T2 group and lowest (P < 0.05) in the T3 and T4 groups. Villus widths in the duodenum and ileum were highest (P < 0.05) in the T2 group, but the T1 group showed highest (P < 0.05) values in the jejunum sections. The T3 and T4 groups showed lowest (P < 0.05) values in villus width in the duodenum, jejunum, and ileum. Thigh yield was highest (P < 0.05) in the T2 group and lowest (P < 0.05) in the T4 group. The T1 group exhibited the highest (P < 0.05) piece yields for leg, wing, and hip-back. The T4 group showed lowest (P < 0.05) leg and wing yields. Moringa leaf powder and agave inulin at a concentration of 15 g/kg in diets did not affect broiler performance, whereas moringa leaf powder improved intestinal morphology and thigh yield, and agave inulin improved leg yield. The results demonstrated benefits of these 2 feed additives to improve intestine health and meat yield in broilers over a 40-day grow-out.


Subject(s)
Agave , Chickens/growth & development , Intestines/anatomy & histology , Inulin/physiology , Meat , Moringa , Agave/chemistry , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Dietary Supplements , Male , Meat/standards , Moringa/chemistry , Plant Leaves/chemistry , Powders , Random Allocation
12.
Foods ; 10(2)2021 Feb 05.
Article in English | MEDLINE | ID: mdl-33562539

ABSTRACT

Non Celiac Wheat Sensitivity (NCWS) is an intolerance to wheat products and individuals with NCWS often adhere to a gluten free diet. However, gluten free diets are often associated with a reduced sensory and nutritional quality. Wheat Germ Agglutinin (WGA) is one of the wheat components linked to NCWS. This study explored the fate of WGA during sourdough fermentation. To assess the role of thiol-exchange reactions and proteolysis, sourdoughs were fermented with Fructilactobacillus sanfranciscensis DSM20451, F. sanfranciscensis DSM20451ΔgshR, which lacks glutathione reductase activity, or Latilactobacillus sakei TMW1.22, with or without addition of fungal protease. The conversion of WGA was determined by size exclusion chromatography of fluorescence-labeled WGA, and by enzyme-linked immunosorbent assay (ELISA). Commercial whole wheat flour contained 6.6 ± 0.7 µg WGA/g. After fermentation with L. sakei TMW1.22 and F. sanfranciscensis DSM20451, the WGA content was reduced (p < 0.05) to 2.7 ± 0.4 and 4.3 ± 0.3 µg WGA/g, respectively, while the WGA content remained unchanged in chemically acidified controls or in doughs fermented with F. sanfranciscensis DSM20451ΔgshR. Protease addition did not affect the WGA content. In conclusion, the fate of WGA during sourdough fermentation relates to thiol-exchange reactions but not to proteolytic degradation.

13.
Nat Mater ; 19(12): 1346-1353, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32778813

ABSTRACT

The combination of well-defined molecular cavities and chemical functionality makes crystalline porous solids attractive for a great number of technological applications, from catalysis to gas separation. However, in contrast to other widely applied synthetic solids such as polymers, the lack of processability of crystalline extended solids hampers their application. In this work, we demonstrate that metal-organic frameworks, a type of highly crystalline porous solid, can be made solution processable via outer surface functionalization using N-heterocyclic carbene ligands. Selective outer surface functionalization of relatively large nanoparticles (250 nm) of the well-known zeolitic imidazolate framework ZIF-67 allows for the stabilization of processable dispersions exhibiting permanent porosity. The resulting type III porous liquids can either be directly deployed as liquid adsorbents or be co-processed with state-of-the-art polymers to yield highly loaded mixed matrix membranes with excellent mechanical properties and an outstanding performance in the challenging separation of propylene from propane. We anticipate that this approach can be extended to other metal-organic frameworks and other applications.

14.
Foods ; 9(7)2020 Jul 16.
Article in English | MEDLINE | ID: mdl-32708800

ABSTRACT

The ingestion of gluten-containing foods can cause wheat-related disorders in up to 15% of wheat consuming populations. Besides the role of gluten, α-amylase/trypsin inhibitors (ATI) have recently been identified as inducers of an innate immune response via toll-like receptor 4 in celiac disease and non-celiac wheat sensitivity. ATI are involved in plant self-defense against insects and possibly in grain development. Notably, they are largely resistant to gastrointestinal proteases and heat, and their inflammatory activity affects not only the intestine, but also peripheral organs. The aim of this study was to understand the changes of ATI throughout the sourdough and yeast-fermented bread-making processes. ATI tetramers were isolated, fluorescein-labelled, and added to a mini-dough bread-making system. When the pH decreased below 4.0 in sourdough fermentation, the ATI tetramers were degraded due to the activation of aspartic proteases, whilst in yeast fermentation, ATI tetramers remained intact. The amylase inhibitory activity after sourdough fermentation decreased significantly, while the concentration of free thiol groups increased. The glutathione reductase activity of Fructilactobacillus sanfranciscensis did not contribute to the reduction of ATI tetramers. Compared to the unfermented wheat, sourdough fermentation was able to decrease the release of pro-inflammatory cytokines monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor alpha (TNF-α) in quantitative ATI extracts added to the human monocytic cell line THP-1. The current data suggest that sourdough fermentation can degrade ATI structure and bioactivity, and point to strategies to improve product development for wheat sensitivity patients.

15.
Acc Chem Res ; 53(6): 1206-1217, 2020 Jun 16.
Article in English | MEDLINE | ID: mdl-32496790

ABSTRACT

ConspectusMetal-organic frameworks (MOFs) and covalent organic frameworks (COFs) are among the most attractive porous materials today. They exhibit outstanding porosity for countless applications such as gas storage, CO2 capture, gas separation, sensing, drug delivery, and catalysis. Moreover, researchers have recently begun to combine MOFs or COFs with other functional materials to obtain composites that boast the respective strengths, and mitigate the respective weaknesses, of each component, enabling enhanced performance in many of the aforementioned applications. Accordingly, development of methods for fabrication of MOFs, COFs, and related composites is important for facilitating adoption of these materials in industry. One promising synthetic technique is spray-drying, which is already well-integrated in manufacturing processes for diverse sectors. It enables rapid, continuous and scalable production of dry microspherical powders in a single step, leading to lower fabrication costs and shorter production times compared to traditional methods.In this Account, we outline our ongoing work on spray-drying synthesis of crystalline porous MOFs, COFs, and related composites. Versatile and tunable, spray-drying can be adapted to perform reactions involving coordination and covalent chemistry for the synthesis of micrometer spherical beads/superstructures of MOFs and COFs. Likewise, MOF- and COF-based composites can be synthesized using similar conditions as those for pure MOFs or COFs, through the simple introduction of additional functional materials into the feed precursor solution or colloid. Interestingly, spray-drying can also be done in water, thus providing the basis for its use as a scalable green method for industrial fabrication of these materials. To date, spray-drying has already been scaled up for pilot production (kilogram scale) of MOFs.

16.
Food Microbiol ; 91: 103507, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32539950

ABSTRACT

Bacillus spp. cause ropy bread spoilage of bread, which is characterized by a rotten fruity odor, followed by discoloration and degradation of the crumb. Bacillus spp. are wheat grain endophytes and form heat resistant endospores, therefore, process hygiene and heating during baking do not prevent ropy spoilage. This study used 8 strains of Bacillus subtilis and Bacillus amyloliquefaciens to determine whether the presence and the copy number of spoVA2mob operon influences survival after baking; in addition, the spoilage phenotype was correlated with the presence of amylolytic enzymes in genomes of Bacillus spp.. The presence and copy number of the spoVA2mob operon had only a minor effect on survival of Bacillus endospores. Strains of B. amyloliquefaciens caused ropy spoilage faster than strains of B. subtilis, this difference correlated to the number and type of extracellular amylases encoded in the genomes of the strains of B. amyloliquefaciens and B. subtilis. The inhibitory effect of sourdough on ropy spoilage was determined by addition of 3-24% sourdough fermented with L. reuteri TMW1.656. Addition of 12% and 24% sourdough, corresponding to a bread pH of 5.93 ± 0.041 and 5.53 ± 0.040, respectively, delayed ropy spoilage for 2 and more than 5 d, respectively. The comparison of addition of 12% sourdough fermented with the reutericyclin producing L. reuteri TMW1.656 and the isogenic reutericyclin-negative strain L. reuteri TMW1.656ΔgtfAΔrtcN demonstrated that reutericyclin produced in sourdough inhibits growth of Bacillus in bread. In conclusion, sourdough inhibits germination of Bacillus spores in bread and the effect of sourdough is enhanced by reutericyclin.


Subject(s)
Bacillus/metabolism , Bacterial Proteins/genetics , Bread/microbiology , Tenuazonic Acid/analogs & derivatives , Amylases/genetics , Amylases/metabolism , Bacillus/classification , Bacillus/genetics , Bacillus/growth & development , Bacterial Proteins/metabolism , DNA Copy Number Variations , Fermentation , Food Microbiology , Hydrogen-Ion Concentration , Limosilactobacillus reuteri/genetics , Limosilactobacillus reuteri/metabolism , Microbial Viability , Operon , Spores, Bacterial/classification , Spores, Bacterial/genetics , Spores, Bacterial/growth & development , Temperature , Tenuazonic Acid/metabolism
17.
ACS Appl Mater Interfaces ; 12(9): 10554-10562, 2020 Mar 04.
Article in English | MEDLINE | ID: mdl-32026677

ABSTRACT

Pollution of water with heavy metals is a global environmental problem whose impact is especially severe in developing countries. Among water-purification methods, adsorption of heavy metals has proven to be simple, versatile, and cost-effective. However, there is still a need to develop adsorbents with a capacity to remove multiple metal pollutants from the same water sample. Herein, we report the complementary adsorption capacities of metal-organic frameworks (here, UiO-66 and UiO-66-(SH)2) and inorganic nanoparticles (iNPs; here, cerium-oxide NPs) into composite materials. These adsorbents, which are spherical microbeads generated in one step by continuous-flow spray-drying, efficiently and simultaneously remove multiple heavy metals from water, including As(III and V), Cd(II), Cr(III and VI), Cu(II), Pb(II), and Hg(II). We further show that these microbeads can be used as a packing material in a prototype of a continuous-flow water treatment system, in which they retain their metal-removal capacities upon regeneration with a gentle acidic treatment. As proof-of-concept, we evaluated these adsorbents for purification of laboratory water samples prepared to independently recapitulate each of two strongly polluted rivers: the Bone (Indonesia) and Buringanga (Bangladesh) rivers. In both cases, our microbeads reduced the levels of all the metal contaminants to below the corresponding permissible limits established by the World Health Organization (WHO). Moreover, we demonstrated the capacity of these microbeads to lower levels of Cr(VI) in a water sample collected from the Sarno River (Italy). Finally, to create adsorbents that could be magnetically recovered following their use in water purification, we extended our spray-drying technique to simultaneously incorporate two types of iNPs (CeO2 and Fe3O4) into UiO-66-(SH)2, obtaining CeO2/Fe3O4@UiO-66-(SH)2 microbeads that adsorb heavy metals and are magnetically responsive.

18.
Rev Med Inst Mex Seguro Soc ; 57(2): 74-81, 2019 Jul 31.
Article in Spanish | MEDLINE | ID: mdl-31618561

ABSTRACT

Background: Esophageal candidiasis (EC) is the most common cause of infectious esophagitis. So far, its main risk factor has been HIV infection; in recent years, EC has been favoured by the increasing of diabetes mellitus, wide-spread use of acid-lowering agents, broad-spectrum antibiotics, and inhaled steroids. In Mexico EC has been poorly studied. Objectives: To determine the clinical and epidemiological characteristics of EC, and to identify its etiological agents as well as its antifungal susceptibility. Methods: Patients who revealed the presence of scattered white spots through an upper gastrointestinal system endoscopy, in a period of one year, in a tertiary care hospital, were included. Samples from patches were collected for microscopic examination, culture, and susceptibility tests. Results: Out of 1763 patients studied, 23 had scattered white spots, and most of them presented Kodsi grade I; 13 were men; half of the patients were between the ages 20 to 40; main comorbidity was liver cirrhosis; use of omeprazole was significant. 22 isolates were obtained from 17 patients. The most frequent species were C. albicans (14) and C. parapsilosis (3). In five cases we found a two-species association v. g. Candida famata with Trichosporon mucoides. Half of the isolates showed resistance to one or several antifungal drugs. Conclusions: EC frequency in this study was similar to other studies' results. Obtained isolates showed high resistance to azolic compounds and to caspofungin, which is relevant information to take a therapeutic decision.


Introducción: la candidiasis esofágica (CE) es la causa más común de esofagitis infecciosa. Su principal factor de riesgo ha sido la infección por VIH. En México ha sido poco estudiada. Objetivos: determinar las características clínico-epidemiológicas de la CE e identificar sus agentes etiológicos y su sensibilidad a antifúngicos. Métodos: se incluyeron pacientes a quienes se les detectaron placas blanquecinas durante una endoscopía esofágica, en un periodo de un año, en un hospital de tercer nivel de atención. Se tomó muestra de las placas para examen microscópico, cultivo, y estudios de sensibilidad. Resultados: de 1763 pacientes estudiados, 23 presentaron placas blanquecinas; 13 fueron hombres; la mitad tenía de 20 a 40 años de edad; la principal comorbilidad fue cirrosis hepática; el uso de omeprazol fue significativo. Se obtuvieron 22 aislados de 17 pacientes; predominaron Candida albicans (14) y Candida parapsilosis (3). En cinco casos se encontró asociación de dos especies v. g. Candida famata con Trichosporon mucoides. La mitad de los aislados mostró resistencia a antimicóticos. Conclusiones: la frecuencia de CE fue similar a la de otras casuísticas. Los aislados obtenidos mostraron resistencia elevada a compuestos azólicos y a caspofungina, información relevante para tomar una decisión terapéutica.


Subject(s)
Candidiasis/microbiology , Esophagitis/microbiology , Adult , Aged , Aged, 80 and over , Candida/classification , Candida/isolation & purification , Candidiasis/chemically induced , Cross-Sectional Studies , Esophagitis/chemically induced , Esophagoscopy , Female , Humans , Male , Mexico , Middle Aged , Prospective Studies , Risk Factors , Tertiary Care Centers , Young Adult
19.
Angew Chem Int Ed Engl ; 58(28): 9512-9516, 2019 Jul 08.
Article in English | MEDLINE | ID: mdl-31087600

ABSTRACT

Herein, we describe a new class of porous composites comprising metal-organic framework (MOF) crystals confined in single spherical matrices made of packed covalent-organic framework (COF) nanocrystals. These MOF@COF composites are synthesized through a two-step method of spray-drying and subsequent amorphous (imine-based polymer)-to-crystalline (imine-based COF) transformation. This transformation around the MOF crystals generates micro- and mesopores at the MOF/COF interface that provide far superior porosity compared to that of the constituent MOF and COF components added together. We report that water sorption in these new pores occurs within the same pressure window as in the COF pores. Our new MOF@COF composites, with their additional pores at the MOF/COF interface, should have implications for the development of new composites.

20.
Rev Med Inst Mex Seguro Soc ; 57(3): 181-186, 2019 05 02.
Article in Spanish | MEDLINE | ID: mdl-31995345

ABSTRACT

Background: Infectious endocarditis of fungal origin is rare but of high mortality. The agents involved are mainly opportunists of the genus Candida and Aspergillus; however other fungi can also cause this disease. Clinical case: The case of a woman who suffered unknown origin intermittent fever for several months; and in who, by blood culture (after lysis-centrifugation) and molecular biology techniques, Histoplasma capsulatum was identified as etiological agent. The histological study showed abundant intracellular yeasts and hyphae in intracardiac vegetations. Conclusion: This first report of infectious endocarditis by H. capsulatum in Mexico highlights the importance of using in addition to manual blood culture (lysis-centrifugation) and histological study, faster and more sensitive diagnostic methods, such as serology and molecular biology, to confirm or rule out an invasive fungal infection and identify the agents.


Introducción: la endocarditis infecciosa de etiología micótica es una patología poco frecuente, pero con elevada mortalidad. Los agentes implicados generalmente son oportunistas de los géneros Candida y Aspergillus; sin embargo, otros hongos también pueden ocasionar la enfermedad. Caso clínico: se presenta el caso de una mujer quien cursó con fiebre intermitente de causa desconocida por varios meses y en la que, por medio de estudios de imagen, hemocultivo manual (después de lisis-centrifugación) y técnicas de biología molecular, se identificó Histoplasma capsulatum. El estudio histológico de las vegetaciones intracardiacas mostró abundantes levaduras e hifas. Conclusión: este primer reporte de endocarditis infecciosa por H. capsulatum en México pone en evidencia la importancia de utilizar, además del hemocultivo manual (lisis-centrifugación) y el estudio histológico, métodos de diagnóstico más rápidos y sensibles, como la serología y la biología molecular, para confirmar o descartar una infección fúngica invasiva e identificar los agentes.


Subject(s)
Endocarditis/microbiology , Histoplasmosis/complications , Endocarditis/epidemiology , Female , Histoplasma/isolation & purification , Histoplasmosis/epidemiology , Humans , Mexico/epidemiology , Middle Aged
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