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1.
Int J Phytoremediation ; 25(6): 746-758, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35914282

RESUMO

Soil pollution is one of the major environmental concerns. Since the inception of the industrial revolution, numerous perilous compounds are being introduced into the environment by various means. Of these, heavy metals are considered the important soil contaminants that present significant peril to human health. While the preventive measures of environmental pollution lie in the awareness of mankind, eliminating the interfering consequences of pollutants that have already been released into the environment is the current challenge. The present work, therefore, aimed to determine the phytoremediation potential of Catharanthus roseus based on contamination indices. The metal concentrations in soil and plant were assessed using Atomic Absorption Spectrophotometry and Inductively Coupled Plasma -Mass Spectrophotometry. The results showed that C. roseus acted as a good tool in remediating industrially contaminated soils. Plants grown under metal stress showed enhanced antioxidant potential. Further, the plant exhibited increased chlorophyll, pectin and lignin content in response to heavy metals, suggesting significant relation between plant metabolism and mental stress. Phytoremediation using plants like C. roseus therefore, can be esthetically pleasing and more publicly acceptable than the disruptive physical and chemical processes currently in use.


The present study was undertaken for the first time to evaluate the potential of Catharanthus roseus to remediate the industrially contaminated soils of Visakhapatnam city. Plant responses to heavy metals were analyzed based on the alterations in antioxidant potential, lignin and pectin content of plants grown in these soils.


Assuntos
Catharanthus , Metais Pesados , Poluentes do Solo , Humanos , Catharanthus/metabolismo , Solo/química , Biodegradação Ambiental , Poluentes do Solo/metabolismo , Metais Pesados/análise , Plantas/metabolismo
2.
Sci Total Environ ; 835: 155508, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35483465

RESUMO

Antibiotics are priority contaminants of emerging concern due to their pseudo-persistence in the environment and contribution to the development of antimicrobial resistance. In solution, antibiotics undergo (de)protonation reactions that affect their UV absorbance and, therefore, photolytic fate in natural and engineered systems. This study employed enhanced spectrophotometric methods to determine the acid dissociation constants (as pKa values) and molar absorption coefficients for 12 fluoroquinolone, 9 sulfonamide, and 7 tetracycline antibiotics of environmental relevance. Molar absorption coefficient heatmaps were generated for all 28 antibiotics at 200-500 nm and pH 1.8-12.2. The data in the heatmaps were deconvoluted to calculate pKa values and specific molar absorption coefficients at each wavelength. All antibiotics had at least one pKa value in the environmentally relevant range of 5.5-8.5, and pKa values were reported for methacycline, moxifloxacin, nadifloxacin, rolitetracycline, sulfadoxine, and sulfapyridine for the first time. Deprotonation of the carboxylic acid associated with pKa,1 (5.5-6.7) exerted the strongest effects on the UV absorbance of fluoroquinolones. For tetracyclines, deprotonation of the tertiary amine at pKa,3 (7.8-10.2) was responsible for major shifts in UV absorbance. Although sulfonamides have conserved pKa sites, no general trends were observed for the molar absorption coefficients. The structural similarity of fluoroquinolones and tetracyclines supported the potential for a class-based approach to identifying molar absorbance as a function of pH. Overall, the reported pKa values and specific molar absorption coefficients will serve as important resources for future studies on antibiotic fate in natural and engineered systems.


Assuntos
Antibacterianos , Fluoroquinolonas , Ácidos , Antibacterianos/química , Sulfanilamida , Sulfonamidas , Tetraciclinas
3.
Autops Case Rep ; 11: e2021260, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307222

RESUMO

BACKGROUND: Intestinal duplications are rare congenital developmental anomalies with an incidence of 0.005-0.025% of births. They are usually identified before 2 years of age and commonly affect the foregut or mid-/hindgut. However, it is very uncommon for these anomalies, to arise in the colon or present during adulthood. CASE PRESENTATION: Herein, we present a case of a 28-year-old woman with a long-standing history of constipation, tenesmus, and rectal prolapse. Colonoscopy results were normal. An abdominal computed tomography (CT) revealed a diffusely mildly dilated redundant colon, which was prominently stool-filled. The gastrografin enema showed ahaustral mucosal appearance of the sigmoid and descending colon with findings suggestive of tricompartmental pelvic floor prolapse, moderate-size anterior rectocele, and grade 2 sigmoidocele. A laparoscopic exploration was performed, revealing a tubular duplicated colon at the sigmoid level. A sigmoid resection rectopexy was performed. Pathologic examination supported the diagnosis. At 1-month follow-up, the patient was doing well without constipation or rectal prolapse. CONCLUSIONS: Tubular colonic duplications are very rare in adults but should be considered in the differential diagnosis of chronic constipation refractory to medical therapy. Due to the non-specific manifestations of this entity, it is rather challenging to make an accurate diagnosis pre-operatively. Surgery remains the mainstay of treatment. Some reports suggest that carcinomas are more prone to develop in colonic/rectal duplications than in other GI tract duplications.

4.
Int J Phytoremediation ; 23(13): 1391-1401, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33735592

RESUMO

Catharanthus roseus (Madagascar periwinkle) is the source of terpenoid indole alkaloids which are minor products in the plants, making their isolation elaborate and costly. The low yield of the alkaloids in the plant combined with their high market price made Catharanthus roseus an important model system for plant biotechnology and secondary metabolism studies. This study highlights the responses of Catharanthus roseus due to metal stress under pot culture conditions. It was observed that metals like zinc and copper showed a positive effect on accumulation of few secondary metabolites in Catharanthus roseus. Accumulation of total alkaloids, phenolics and flavonoids in the plants were observed to increase with increasing concentrations of these metal treatments given to growing plants. Similarly, plants grown in industrially contaminated soils also showed varying alkaloid, phenolics and flavonoid accumulation in comparison to those grown in garden soil. Higher metal contaminations in the soil lead to higher production of certain phytochemicals in different plant parts.


Assuntos
Alcaloides , Catharanthus , Biodegradação Ambiental , Compostos Fitoquímicos , Zinco
5.
Autops. Case Rep ; 11: e2021260, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1249020

RESUMO

Background Intestinal duplications are rare congenital developmental anomalies with an incidence of 0.005-0.025% of births. They are usually identified before 2 years of age and commonly affect the foregut or mid-/hindgut. However, it is very uncommon for these anomalies, to arise in the colon or present during adulthood. Case presentation Herein, we present a case of a 28-year-old woman with a long-standing history of constipation, tenesmus, and rectal prolapse. Colonoscopy results were normal. An abdominal computed tomography (CT) revealed a diffusely mildly dilated redundant colon, which was prominently stool-filled. The gastrografin enema showed ahaustral mucosal appearance of the sigmoid and descending colon with findings suggestive of tricompartmental pelvic floor prolapse, moderate-size anterior rectocele, and grade 2 sigmoidocele. A laparoscopic exploration was performed, revealing a tubular duplicated colon at the sigmoid level. A sigmoid resection rectopexy was performed. Pathologic examination supported the diagnosis. At 1-month follow-up, the patient was doing well without constipation or rectal prolapse. Conclusions Tubular colonic duplications are very rare in adults but should be considered in the differential diagnosis of chronic constipation refractory to medical therapy. Due to the non-specific manifestations of this entity, it is rather challenging to make an accurate diagnosis pre-operatively. Surgery remains the mainstay of treatment. Some reports suggest that carcinomas are more prone to develop in colonic/rectal duplications than in other GI tract duplications.


Assuntos
Humanos , Masculino , Adulto , Anormalidades Congênitas , Colo/anormalidades , Constipação Intestinal/complicações , Diagnóstico Diferencial
6.
Environ Sci Technol ; 53(22): 13323-13331, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31635452

RESUMO

The tapping of municipal wastewater for potable reuse significantly enhances drinking water supply in drought-stricken regions worldwide. Membrane-based potable reuse treatment trains commonly employ ultraviolet-based advanced oxidation processes (UV-AOPs) to degrade trace organic contaminants in water to produce high-quality recycled water. Hydrogen peroxide (H2O2) is used as the default photo-oxidant. Meanwhile, chloramines, which are added to prevent biofouling, pass through the membranes and impact the treatment efficiency of UV-AOP. Water reuse facilities therefore face the dilemma of optimizing H2O2 (an added photo-oxidant) and chloramines (a carry-over photo-oxidant) doses. Utilizing a uniquely designed pilot-scale reactor and real-time recycled water, we evaluated treatment efficiencies of UV-AOP on six important indicator contaminants, with monochloramine (NH2Cl) and H2O2 as photo-oxidants. Hydroxyl radical (HO•) and reactive chlorine species, such as the chlorine atom (Cl•) and chlorine dimer (Cl2•-), were the major reactive species. Overall, radicals generated from photolysis of NH2Cl alone achieved removal of indicator compounds, which can be further improved by optimizing UV fluence, i.e., the UV dose. Furthermore, the addition of H2O2 enhanced HO• formation and improved contaminant removal. However, the addition of H2O2, when the background NH2Cl level was above 2 mg L-1 (as Cl2), provided limited improvement in treatment efficiency. These trade-offs between chloramine and H2O2 as oxidants, and the recommended optimization of the associated effective UV fluence, are critical for energy-efficient and cost-effective potable reuse to address the challenges of global water scarcity.


Assuntos
Água Potável , Poluentes Químicos da Água , Purificação da Água , Cloraminas , Peróxido de Hidrogênio , Oxirredução , Raios Ultravioleta , Águas Residuárias
7.
Int J Biol Macromol ; 114: 556-564, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29578020

RESUMO

Therapeutic value of allelochemicals in inflammatory disorders and the potential drug targets need to be elucidated to alleviate tissue and vascular injury. Natural anti-inflammatory agents are known to cause minimal adverse effects. Presence of different secondary metabolites (allelochemicals), protease inhibitors like soap nut trypsin inhibitor (SNTI) from Sapindus trifoliatus and allied compounds from natural sources cannot be blithely ignored as natural therapeutics. In the present study, SNTI, a prospective protease inhibitor isolated from the seeds of Sapindus trifoliatus were subjected to docking against three isoforms of Phospholipase A2 (PLA2) molecules of the inflammatory pathways which are localized in the membrane, cytosol and pancreas. Eleven ligand molecules were selected from Sapindus trifoliatus and docked against membrane, cytosolic and pancreatic PLA2. Cytosolic PLA2 showed a strong inhibition by Kampferol, a secondary metabolite from seed endosperm of Sapindus trifoliatus. SNTI showed best interaction with membrane PLA2 in both in silico as well as in in vitro studies. SNTI showed IC50 value of 29.02 µM in in vitro assay. Docking interaction profiles and in vitro studies validate selected molecules from Sapindus trifoliatus as immunomodulators and can mollify inflammatory responses.


Assuntos
Fatores Imunológicos , Simulação de Acoplamento Molecular , Fosfolipases A2/química , Proteínas de Plantas , Sapindus/química , Inibidores da Tripsina , Animais , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Isoenzimas/química , Isoenzimas/metabolismo , Camundongos , Fosfolipases A2/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/uso terapêutico , Inibidores da Tripsina/química , Inibidores da Tripsina/isolamento & purificação , Inibidores da Tripsina/uso terapêutico
8.
Environ Sci Technol ; 51(21): 12310-12320, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-28952731

RESUMO

This study examined the photolytic fate of the chlortetracycline (CTC), ciprofloxacin (CIP), roxarsone (ROX), and sulfamethoxazole (SMX) antibiotics in agriculturally relevant matrices. The observed photodegradation kinetics for antibiotics in solutions containing dissolved organic matter (DOM) from three poultry litter extracts was modeled to identify contributions from direct and indirect photolysis. Suwannee River natural organic matter (SRN) was used as a surrogate DOM standard. Poultry litter-derived DOM generated lower concentrations of reactive species compared to SRN. Direct photolysis was the dominant transformation mechanism for CIP, whereas CTC, ROX, and SMX were sensitized by 3DOM* and 1O2. The impacts of agricultural DOM on photodegradation of antibiotics were identified in terms of pseudo-first-order rate constants for formation of reactive species and second-order rate constants for reaction of reactive species with DOM. Solutions containing poultry litter-derived DOM generated similar levels of 3DOM* and 1O2, enhancing degradation of CTC, ROX, and SMX. The reactivity of SMX was markedly different in solutions containing poultry litter DOM compared to solutions with SRN, indicating that the photolytic fate of select antibiotics varies for agricultural and surface water matrices. As the majority of antibiotics are consumed by animals, these findings provide new insight into agriculturally relevant transformation mechanisms and kinetics.


Assuntos
Antibacterianos , Fotólise , Poluentes Químicos da Água , Animais , Aves Domésticas , Sulfametoxazol
9.
Environ Sci Technol ; 51(14): 8036-8047, 2017 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-28603977

RESUMO

Parallel factor analysis (PARAFAC) applied to fluorescence excitation emission matrices (EEMs) allows quantitative assessment of the composition of fluorescent dissolved organic matter (DOM). In this study, we fit a four-component EEM-PARAFAC model to characterize DOM extracted from poultry litter. The data set included fluorescence EEMs from 291 untreated, irradiated (253.7 nm, 310-410 nm), and oxidized (UV-H2O2, ozone) poultry litter extracts. The four components were identified as microbial humic-, terrestrial humic-, tyrosine-, and tryptophan-like fluorescent signatures. The Tucker's congruence coefficients for components from the global (i.e., aggregated sample set) model and local (i.e., single poultry litter source) models were greater than 0.99, suggesting that the global EEM-PARAFAC model may be suitable to study poultry litter DOM from individual sources. In general, the transformation trends of the four fluorescence components were comparable for all poultry litter sources tested. For irradiation at 253.7 nm, ozonation, and UV-H2O2 advanced oxidation, transformation of the humic-like components was slower than that of the tryptophan-like component. The opposite trend was observed for irradiation at 310-410 nm, due to differences in UV absorbance properties of components. Compared to the other EEM-PARAFAC components, the tyrosine-like component was fairly recalcitrant in irradiation and oxidation processes. This novel application of EEM-PARAFAC modeling provides insight into the composition and fate of agricultural DOM in natural and engineered systems.


Assuntos
Análise Fatorial , Substâncias Húmicas , Aves Domésticas , Animais , Fezes/química , Peróxido de Hidrogênio , Espectrometria de Fluorescência
10.
Environ Sci Technol ; 50(17): 9533-42, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27479003

RESUMO

Three fluoroquinolone-to-fluoroquinolone antibiotic transformations were monitored during UV-C irradiation processes. In particular, the following reactions were observed: enrofloxacin-to-ciprofloxacin, difloxacin-to-sarafloxacin, and pefloxacin-to-norfloxacin. The apparent molar absorptivity and fluence-based pseudo-first-order rate constants for transformation of the six fluoroquinolones by direct photolysis at 253.7 nm were determined for the pH 2-12 range. These parameters were deconvoluted to calculate specific molar absorptivity and fluence-based rate constants for cationic, zwitterionic, and anionic fluoroquinolone species. For a typical disinfection fluence of 40 mJ/cm(2), the apparent transformation efficiencies were inflated by 2-8% when fluoroquinolone products were not considered; moreover, the overall transformation efficiencies at 400 mJ/cm(2) varied by up to 40% depending on pH. The three product antibiotics, namely ciprofloxacin, sarafloxacin, and norfloxacin, were found to be equally or more potent than the parent fluoroquinolones using an Escherichia coli-based assay. UV treatment of a solution containing difloxacin was found to increase antimicrobial activity due to formation of sarafloxacin. These results highlight the importance of considering antibiotic-to-antibiotic transformations in UV-based processes.


Assuntos
Antibacterianos , Fotólise , Ciprofloxacina , Fluoroquinolonas , Cinética , Norfloxacino
11.
PDA J Pharm Sci Technol ; 69(2): 215-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25868988

RESUMO

Pharmaceuticals and other xenobiotic molecules are being increasingly detected in drinking water, food crops, and breast milk. This issue represents a novel toxicological concern, especially for sensitive populations like pregnant women and breastfeeding infants. This commentary calls for more interdisciplinary research efforts focused on elucidating the transfer of contaminants of emerging concern from mother to child, as well as the relevant toxicological impacts on the child. The need for more tangible efforts to reduce pharmaceutical loads in environmental systems is also highlighted.


Assuntos
Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Xenobióticos/toxicidade , Aleitamento Materno/efeitos adversos , Exposição Ambiental/prevenção & controle , Monitoramento Ambiental/métodos , Poluentes Ambientais/química , Feminino , Humanos , Lactente , Leite Humano/química , Gravidez , Populações Vulneráveis , Poluentes Químicos da Água/toxicidade , Xenobióticos/química
12.
Water Res ; 70: 74-85, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25514660

RESUMO

Roxarsone (ROX) and nitarsone (NIT) are used as additives in animal feeding operations and have been detected in animal manure, agricultural retention ponds, and adjacent surface waters. This work investigates treatment of organoarsenicals using UV-based treatment processes, namely UV irradiation at 253.7 nm and the UV-H2O2 advanced oxidation process. The apparent molar absorptivity was mapped for ROX and NIT across pH and wavelength. For UV irradiation at 253.7 nm, the fluence-based pseudo-first order rate constant (kp(')) and effective quantum yield (Φ) for ROX were 8.10-29.7 × 10(-5) cm(2)/mJ and 2.34-8.37 × 10(-3) mol/E, respectively; the corresponding constants were slightly lower for NIT. The observed rate constants are higher during advanced oxidation (e.g., kp,ROX(')=3.92(±0.19)-217(±48) × 10(-4) cm(2)/mJ). Second order rate constants for organoarsenical transformation by hydroxyl radicals were determined to be 3.40(±0.45) × 10(9) and 8.28(±0.49) × 10(8) M(-1)s(-1) for ROX and NIT, respectively. Solution pH and nitrate concentration did not significantly impact ROX transformation during advanced oxidation; however, bicarbonate and dissolved organic matter from chicken litter reduced ROX transformation through hydroxyl radical scavenging. Inorganic arsenic was the predominant transformation product of ROX during UV-H2O2 treatment.


Assuntos
Arsenicais/química , Peróxido de Hidrogênio/química , Compostos Orgânicos/química , Roxarsona/química , Raios Ultravioleta , Oxirredução
13.
Surg Obes Relat Dis ; 10(5): 795-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25012775

RESUMO

BACKGROUND: Few treatments for idiopathic and diabetic gastroparesis exist beyond symptom management, and no study has described gastric surgery for gastroparesis in obese and morbidly obese patients. The objective of this study was to describe treatment of recalcitrant gastroparesis in obese adults with Roux-en-Y gastric bypass (RYGB) surgery. METHODS: A retrospective review was conducted of adult patients who underwent laparoscopic RYGB. Clinical data pre- and postsurgery and at a follow-up of up to 2 years were reviewed. Total symptom scores for gastroparetic symptom severity and frequency were compared presurgery and at follow-up using paired t tests. RESULTS: Seven obese and morbidly obese patients (body mass index [BMI] = 39.5, range = 33-54; 6 women) with idiopathic or diabetic gastroparesis reported marked symptom improvement, and total symptom scores significantly decreased after RYGB. All 4 patients who were taking prokinetics preoperatively no longer required their medication after surgery. Three patients required prolonged treatment with antinausea medications in the postoperative period. Mean BMI change was 9.1 units and mean percent excess weight lost was 71.6 lbs. No perioperative complications were experienced. Two required readmissions due to various concerns (dysphagia, nausea, anastomotic ulcer). CONCLUSIONS: In our cohort, no patients required the use of prokinetics after surgery and everyone experienced significant improvement in symptoms. Importantly, we found that RYGB is a safe surgical treatment for gastroparesis in obese patients. Our results indicate that gastroparesis, primarily believed to result in being underweight, can present in morbid obesity and can be markedly improved with RYGB.


Assuntos
Complicações do Diabetes/cirurgia , Derivação Gástrica/métodos , Gastroparesia/cirurgia , Laparoscopia/métodos , Obesidade/cirurgia , Adulto , Índice de Massa Corporal , Doença Crônica , Feminino , Gastroparesia/complicações , Humanos , Masculino , Obesidade/complicações , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Redução de Peso
15.
Indian J Exp Biol ; 42(11): 1117-22, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15587120

RESUMO

A cobalt-resistant wall-less mutant of N. crassa (Cor-sl) characterized previously was also found to be 3-fold more resistant to nickel when compared to the parent wall-less mutant (W-sl). The Cor-sl strain accumulates relatively lower amounts of nickel when compared to W-sl. Sub-cellular fractionation showed significant quantities of nickel to be associated with nuclear and mitochondrial fractions in both the wall-less mutants. However significant differences were observed in vacuolar fractions of W-sl and Cor-sl strains. Fractionation of cell-free extracts on Sephadex G-10 column resolved nickel into two peaks, of which the peak II in Cor-sl constituted 70% of nickel, while the same in W-sl was about 30%. A 3-fold increase in histidine content was observed in case of Cor-sl as compared to W-sl strain, suggesting its role in Ni-resistance.


Assuntos
Parede Celular/fisiologia , Cobalto/farmacologia , Cobalto/toxicidade , Farmacorresistência Fúngica , Mutação/genética , Neurospora crassa/efeitos dos fármacos , Níquel/toxicidade , Cobalto/análise , Histidina/metabolismo , Neurospora crassa/citologia , Neurospora crassa/genética , Níquel/análise , Frações Subcelulares
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