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1.
J Colloid Interface Sci ; 607(Pt 2): 1973-1985, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34695746

ABSTRACT

A facile approach is presented to synthesize the ionic liquid-grafted graphene oxide (GO-ImOH) for fast and efficient adsorptive removal of cationic dyes. A coupling reaction between the hydroxyl terminal of imidazolium ionic liquid and the carboxylic group of GO, yielded the GO-ImOH hybrid material. The higher surface negative charge (-32 mV) and excellent dispersibility make the GO-ImOH an efficient adsorbent for cationic dyes. The GO-ImOH showed excellent removal efficiency for methylene blue (cationic dye), whereas it could adsorb only 22% methyl orange (anionic dye). The GO-ImOH displayed significantly higher adsorptive removal capacity for cationic dye compared to that of GO adsorbent. The chemical and structural features of GO-ImOH and spectroscopic analyses (FTIR and Raman) of pristine and recovered GO-ImOH adsorbent suggested multiple adsorptive interaction pathways (electrostatic, π-cation, π-π interactions, and hydrogen linkages) between the GO-ImOH adsorbent and the dye molecules. The work paves a new direction for the development of ionic liquids-modified 2D nanomaterials for efficient and fast adsorptive removal of organic pollutants, where the adsorptive sites on the surface of 2D nanomaterials can be tuned by selecting the desired functionalities from a diversified library of cations and anions of ionic liquids.


Subject(s)
Graphite , Ionic Liquids , Water Pollutants, Chemical , Adsorption , Coloring Agents , Water Pollutants, Chemical/analysis
2.
J Colloid Interface Sci ; 608(Pt 3): 2870-2883, 2022 Feb 15.
Article in English | MEDLINE | ID: mdl-34802756

ABSTRACT

A wide range of organic pollutants in industrial effluents, agricultural runoff, and domestic discharges are exacerbating water scarcity, leading to water-borne ailments, and adversely affecting the marine ecosystem and biodiversity. The efficient, sustainable, and cost-effective materials need to be addressed urgently for the removal of organic pollutants. Herein, ultra-light (0.018 g.cm-3) and highly porous (96.4%) composite aerogel is prepared by gelatinization of graphene oxide with fruit waste-derived cellulose. The macroscopic porosity generated by interconnecting cellulosic skeleton and graphene oxide sheets via hydrogen bonding network provided ample avenues for transport and diffusion of organic dyes-enriched wastewater throughout the cellulose-graphene oxide composite aerogel (CGA). Consequently, organic dyes are efficiently adsorbed by easily accessible surface sites distributed throughout the CGA. The size, charge, and chemical structure of organic dyes along with textural features and accessible surface active sites of CGA governed the adsorption process. The spectroscopic analyses based on FTIR, Raman, and XPS measurements suggest electrostatic, n-π, π-π, cation-π interactions, dipole-dipole hydrogen, and Yoshida hydrogen linkages as major interactive pathways for the adsorption of organic dyes by the CGA. Moreover, the composite aerogel furnished an excellent recyclability for the adsorptive removal of organic pollutants from wastewater. The present work promises the potential of 2D nanostructured layered materials and fruit-waste-derived composite aerogels for sustainable utilization in wastewater treatment, which can be an excellent step towards water security.


Subject(s)
Graphite , Water Pollutants, Chemical , Adsorption , Cellulose , Coloring Agents , Ecosystem , Fruit/chemistry , Water Pollutants, Chemical/analysis
3.
ACS Appl Mater Interfaces ; 14(1): 1334-1346, 2022 Jan 12.
Article in English | MEDLINE | ID: mdl-34941265

ABSTRACT

Tungsten disulfide (WS2) exhibits intriguing tribological properties and has been explored as an excellent lubricious material in thin-film and solid lubricants. However, the poor dispersibility of WS2 has been a major challenge for its utilization in liquid lubricant applications. Herein, a top-down integrated approach is presented to synthesize oxygenated WS2 (WS2-O) nanosheets via strong acid-mediated oxidation and ultrasound-assisted exfoliation. The ultrathin sheets of WS2-O, comprising 4-7 molecular lamellae, exhibit oxygen/hydroxyl functionalities. The organosilanes having variable surface-active leaving groups (chloro and ethoxy) are covalently grafted, targeting the hydroxyl/oxygen functionalities on the surface of WS2-O nanosheets. The grafting of organosilanes is governed by the reactivity of chloro and ethoxy leaving groups. The DFT calculations further support the covalent interaction between the WS2-O nanosheets and organosilanes. The alkyl chain-functionalized WS2-O nanosheets displayed excellent dispersibility in mineral lube base oil. A minute dose of chemically functionalized-WS2 (0.2 mg.mL-1) notably enhanced the tribological properties of mineral lube oil by reducing the friction coefficient (52%) and wear volume (79%) for a steel tribopair. Raman analysis of worn surfaces revealed WS2-derived lubricious thin film formation. The improved tribological properties are attributed to ultralow thickness, stable dispersion, and low shear strength of chemically functionalized WS2 nanosheets, along with protective thin film formation over the contact interfaces of a steel tribopair. The present work opens a new avenue toward exploiting low-dimensional nanosheets for minimizing energy losses due to high friction.

4.
Orthop Rev (Pavia) ; 12(2): 8394, 2020 Aug 06.
Article in English | MEDLINE | ID: mdl-32922695

ABSTRACT

Periprosthetic joint infection (PJI) is a catastrophic complication of total knee arthroplasty (TKA) adding significant costs to the health care system with increasing morbidity and mortality. The goal of this study was to develop a prognostic scoring system that could risk-stratify patients undergoing TKA for the risk of PJI. The study included 150 patients who underwent primary TKA from June 2012 to February2016. There were 60 patients in group I who were not risk stratified using the scoring system, while 90 patients were assigned to group II and were prospectively assigned scores based on the scoring system. Points were assigned for each pre-op variable and a scoring chart was developed. Group II patients scoring 4 or more were counseled to optimize their modifiable risk factors before proceeding with surgery. Retrospective chart review was done for patients in group I to find out their risk score for the study purpose. Nine out of 60 patients in group I were found to have score above 4 based on the chart review, of which 4 patients got infected (P<0.05). None of the group II patients got infected after TKA. In conclusion, our scoring system is an objective scoring system for preoperative risk stratification of patients undergoing TKA, thus helping identification and optimization of the risk factors preoperatively to decrease the risk of PJI.

5.
ACS Appl Mater Interfaces ; 12(27): 30720-30730, 2020 Jul 08.
Article in English | MEDLINE | ID: mdl-32524815

ABSTRACT

Two-dimensional transition-metal dichalcogenides possess inherent structural characteristics that can be harnessed for enhancement of tribological properties by making them dispersible in lube media. Here, we present a hydrothermal approach to preparing MoS2 nanosheets comprising 4-10 molecular lamellae. A structural-defect-mediated route for grafting of octadecylamine (ODA) on MoS2 nanosheets is outlined. The unsaturated d orbitals of Mo at the sulfur vacancies on the MoS2 surface are coupled with the electron-rich nitrogen center of ODA and yield ODA-functionalized MoS2 (MoS2-ODA). The MoS2-ODA nanosheets exhibit good dispersibility in lube base oil and are used as an additive (optimized dose: 0.1 mg·mL-1) to mineral oil. It is shown that even at low concentration, MoS2-ODA nanosheets significantly reduce the friction (48%) and wear (44%). Microscopy (field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM)) and spectroscopy (Raman and elemental mapping) analyses of worn scars revealed the formation of MoS2-based protective thin films for lowering of friction and wear. This work, therefore, presents a pathway for low-friction lubricants by deploying functionalized low-dimensional material systems.

6.
J Colloid Interface Sci ; 541: 150-162, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-30685610

ABSTRACT

Alkylated graphene oxide (GO)/reduced graphene oxide (rGO) are prepared by covalent interaction with octadecyltrichlorosilane (OTCS) and octadecyltriethoxysilane (OTES). The variable oxygen functionalities in the GO/rGO and hydrolysis rate of octadecylsilanes having different leaving groups viz. trichloro and triethoxy found to govern the grafting density of octadecyl chains on the GO and rGO. FTIR, XPS, and TGA results revealed a higher grafting of octadecyl chains in the GO-OTCS, whereas the rGO-OTES exhibited minimum grafting. The van der Waals interaction between the octadecyl chain of alkylated GO/rGO and octadecenyl chains of polyol ester makes alkylated GO/rGO dispersible in the polyol lube base oil. The dispersion stability is collectively driven by grafting density of octadecyl chains and presence of oxygen functionalities in the GO/rGO. Tribological properties in terms of the coefficient of friction and wear scar diameter revealed a good correlation with the structure of alkylated GO/rGO and their dispersion stability in the polyol lube base oil. Raman analysis of the worn surface revealed the sheared-induced deposition of a graphene-based tribo-thin film, which reduced the friction and protected the tribo-interfaces against the wear.

7.
J Orthop Case Rep ; 10(1): 22-25, 2019.
Article in English | MEDLINE | ID: mdl-32547973

ABSTRACT

INTRODUCTION: Spontaneous recurrent hemarthrosis of the knee following a total knee arthroplasty is a rare complication with varying time of onset from 2 months to 18 years. It needs a prompt diagnosis and treatment to prevent complications of stiffness, chronic pain, and limited function. We present a case of spontaneous recurrent hemarthrosis presenting at 3 months following a total knee arthroplasty with a follow-up to 1 year. CASE REPORT: A 66-year-old male presented at 3 months following a right total knee arthroplasty with a history of increased pain and swelling of the knee joint. Initially, he was treated with anti-inflammatories when the pain and swelling recurred, an aspiration demonstrated hemarthrosis of the knee. Further evaluation demonstrated no infection, a femoral angiography demonstrated prominence of medial superior and inferior geniculate arteries with a tumor blush appearance. Therapeutic embolization of both the arteries resulted in complete resolution of the symptoms in 1 month with return of full knee function. At the end of 1-year follow-up, the patient had return of full knee function with no pain and no recurrence. CONCLUSION: An algorithmic approach is helpful in identifying the etiology of spontaneous recurrent hemarthrosis of knee and a course of conservative treatment should always be the first line of treatment. Angiography and selective arterial embolization of the geniculate arteries can be an effective treatment in the management of recurrent spontaneous hemarthrosis.

8.
J Colloid Interface Sci ; 513: 666-676, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29207349

ABSTRACT

Shear-induced transfer of graphene on the contact interfaces was studied by microscopic and spectroscopic analyses of steel balls lubricated with chemically functionalized graphene-based mineral lube base oil (SN-150). The 3,5-di-tert-butyl-4-hydroxybenzaldehyde (DtBHBA) grafted-graphene (Gr-DtBHBA) was prepared by two-steps approach using graphene oxide as a precursor. Chemical and structural features of Gr-DtBHBA are probed by FTIR, XPS, Raman, TGA, and HRTEM analyses. The van der Waals interaction between the tertiary-butyl group in the Gr-DtBHBA and hydrocarbon chains of mineral lube base oil facilitates the dispersion of Gr-DtBHBA in the SN-150 lube base oil, which is very important for the optimized performance of Gr-DtBHBA as a lubricant additive. The minute dosing (0.2-0.8 mg mL-1) of the Gr-DtBHBA in the SN-150 lube base oil showed the significant reduction in the coefficient of friction (40%) and wear scar diameter (17%) under the rolling contact between steel balls. The microscopic and EDX analysis of the worn area suggested the role of Gr-DtBHBA nanosheets for enhanced tribo-performance of the SN-150 lube base oil. A detailed Raman study of the worn area of steel ball revealed the deposition of a graphene-based tribo thin film in the forms of irregular patches. The shear-induced deposition of graphene thin film on the contact interfaces reduced the friction and protected the tribo-surfaces against the wear.

9.
Indian J Microbiol ; 57(2): 257-259, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28611506

ABSTRACT

There is a general impression in the scientific community in our country that the way science is taught, leant and the work culture of research and management of academic and research institutions is not conducive to cutting edge research, innovation and making world leaders. Mentoring continues to be poor with some exceptions. Very often, senior scientists with long innings in science teaching and research express anguish at the status quo in spite of a number of policy documents and recommendations for change. Indian science culture (teaching, research as well as administration) is a matter of prime concern and the issues cannot be pushed under the carpet if we desire a qualitative change. Most of the institutions of higher learning churn out graduates and post graduates who are largely unemployable. There are concerns on the number of Ph.Ds and not on the quality of Ph.D. One major consequence of the weak post graduates and Ph.Ds is the non-availability of competent faculty. Weakness and lack of interest in science learning starts from school. Learning continues to be by rote which is the prime reason for our low global rank in science and mathematics competence. Teaching and research apart there are umpteen other issues in over all culture of institutions and universities engaged in science teaching and research. Few oases of excellence are exceptions in the vast pool of mediocrity. Some points which need prime attention are: adoption of a tenure track system on the pattern of US institutions; feedback on and evaluation of teaching and mentoring; bottom up approach for candid feedback on issues which require long term solutions for efficiency and sound deliverables, cultivating the culture of working in front line areas, full transparency in working and an all out exit from culture of feudalism. This transformation needs commitment on the part of the politicians who man the respective departments of science education, research and human resource development. I am sure such a cultural change and paradigm shift from the status quo does not need extra funds and can be surely ushered in without money.

10.
Phys Chem Chem Phys ; 19(9): 6433-6442, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28140414

ABSTRACT

The alkyl chain length of trioctylalkylammonium bis(salicylato)borates (N888n-BScB; n = 6, 8, 10 and 12) was varied to prepare a series of room-temperature ionic liquids, and then their viscosity and rheological properties were investigated. Besides the omnipresent Coulombic interactions, other interactive forces such as van der Waals interactions, hydrogen bonding, inductive forces, dipole-dipole interactions, etc., collectively determine the physicochemical properties of N888n-BScB ionic liquids. The van der Waals interactions and structural geometry of the ammonium cation (N888n) primarily organized the packing orientation of N888n-BScB ionic liquids and controlled their viscosity and rheological properties as a function of the alkyl chain length. The symmetric cation (N8888) increased the viscosity owing to closer packing driven by van der Waals interactions. The N888n-BScB ionic liquids exhibited non-Newtonian shear thinning behaviour. Furthermore, the decrease in viscosity at higher shear rates indicated that interactive forces in the N888n-BScB ionic liquids were disrupted. These ionic liquids, as lubricants, exhibited significantly lower friction (40-50%) and wear (45-69%) in comparison to PEG 300 synthetic lubricating oil. The degrees of reduction in friction and wear were largely influenced by the chain length of the alkyl group. The N888n-BScB ionic liquids with longer alkyl chains were strongly adsorbed on sliding surfaces and provided better lubrication properties than those with shorter alkyl chains. As a result, the coefficients of friction and wear were decreased by increasing the chain length in N888n-BScB ionic liquids. The tribologically induced adsorption of the BScB anion on metal surfaces, electrostatic interactions between ions, the compact and rigid structure of the BScB anion and van der Waals interactions provided by longer alkyl chains in the N888n cation collectively formed a tribochemical thin film of low shear strength, which resulted in a reduction in friction and the avoidance of direct contact between the aluminium and steel tribopair.

11.
Phys Chem Chem Phys ; 18(33): 22879-88, 2016 Aug 17.
Article in English | MEDLINE | ID: mdl-27484045

ABSTRACT

Hexagonal boron nitride nanoplatelets (h-BNNPs), which are structurally analogous to graphene, were prepared via the ultrasound-assisted exfoliation of h-BN powder using N-methyl pyrrolidone as the solvent. The alkylamines with variable alkyl chains and electron-rich nitrogen atoms were grafted onto the boron sites of the h-BNNPs based on Lewis acid-base chemistry. The grafting of the alkylamines onto the h-BNNPs was confirmed using FTIR, XPS, TGA and (13)C SSNMR analyses. The crystalline and structural features of the alkylamine-functionalized h-BNNPs were studied using XRD and HRTEM analyses. The TGA and FTIR results revealed a higher grafting of octadecylamine (ODA) on the h-BNNPs compared to trioctylamine (TOA). The cohesive interaction between the alkyl chains grafted onto the h-BNNPs and the hydrocarbon chains of mineral lube base oil facilitates the dispersion of the alkylamine-functionalized h-BNNPs. The TOA-grafted h-BNNPs (h-BNNPs-TOA) exhibited long-term dispersion stability compared to the ODA-grafted h-BNNPs and this was attributed to a higher degree of van der Waals interactions between the octyl chains of the TOA molecules grafted onto the h-BNNPs and the hydrocarbon chains of the mineral lube base oil. The tribo-performance of the h-BNNPs-TOA as an additive to mineral lube base oil was evaluated in terms of the coefficient of friction and wear using ball-on-disc contact geometry. A minute dosing (0.02 mg mL(-1)) of h-BNNPs-TOA significantly improved the lubrication characteristics of the mineral lube base oil and showed a 35 and 25% reduction of friction and wear, respectively. The presence of boron and nitrogen on the worn scar of an aluminium disc, as deduced from elemental mapping, confirmed the formation of a tribo-chemical thin film of h-BN lamellae on the contact interfaces, which not only reduced the friction but also protected the contact interfaces against undesirable wear events.

12.
Phytochemistry ; 130: 22-46, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27374482

ABSTRACT

The genus Agave comprises more than 400 species with geographical presence in the tropical and sub-tropical regions of the world. These plants have a rich history of folkloric use and are known for a wide spectrum of applications. Secondary metabolites of diverse chemical classes have been reported from Agave species. Owing to their pharmacological significance, the steroidal saponins of Agave have caught the attention of phytochemists, biologists and drug discovery scientists. The present review describes 141 steroidal saponins and sapogenins and covers the literature published from 1970 to 2015. It is a comprehensive and coherent presentation of the structures, methods of chemical profiling, structure elucidation and biological activities of the saponins and sapogenins reported from Agave. The article provides a perspective of the research on steroidal compounds of Agave.


Subject(s)
Agave/chemistry , Saponins , Agave/genetics , Glycosides/chemistry , Glycosides/isolation & purification , Glycosides/pharmacology , Molecular Structure , Sapogenins/chemistry , Sapogenins/isolation & purification , Sapogenins/pharmacology , Saponins/chemistry , Saponins/isolation & purification , Saponins/pharmacology , Stereoisomerism , Steroids/chemistry , Steroids/isolation & purification , Steroids/pharmacology , Sterols/chemistry , Sterols/isolation & purification , Sterols/pharmacology
13.
J Child Orthop ; 10(3): 179-84, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27084780

ABSTRACT

INTRODUCTION: Avascular necrosis (AVN) is a serious complication of treatment for developmental dysplasia of the hip. There is ongoing controversy regarding AVN and its influence on hip development following medial open reduction (MOR). PURPOSE: The aim of our study was to (1) determine the long-term prevalence of AVN following MOR, (2) evaluate hip development after MOR, and (3) identify predictors of AVN and radiographic outcome at skeletal maturity after MOR. METHODS: A retrospective cohort analysis of 60 patients (70 hips) who underwent MOR with a mean follow-up of 10.83 years (5.23-16.74) was conducted. AVN was recorded according to Bucholz and Ogden classification and radiographic outcome based on Severin grading. AVN and hip morphology related to length of follow-up were evaluated. Chi-squared and t-tests were used to identify relationships between AVN and other variables. Logistic regression was used to assess predictors of AVN and Severin outcome. RESULTS: The rate of clinically significant AVN (types 2-4) following MOR was 32.9 % with type 2 accounting for 82.6 % of these cases. While early acetabular development was satisfactory, long-term outcome was unsatisfactory in 26 % of cases with AVN (vs 8.7 % of cases without AVN). A higher rate of AVN was identified when hips were immobilized in ≥60° of abduction postoperatively. A higher rate of poor Severin outcome was identified in hips with AVN. CONCLUSIONS: Our findings suggest that there is a high rate of AVN and unsatisfactory long-term outcome following MOR. AVN remains a significant concern following MOR surgery for developmental dysplasia of the hip that may not be apparent until long-term evaluation.

14.
Indian J Microbiol ; 55(3): 341-4, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26063945

ABSTRACT

Ethics are a set of moral principles and values a civilized society follows. Doing science with principles of ethics is the bedrock of scientific activity. The society trusts that the results and the projected outcome of any scientific activity is based on an honest and conscientious attempt by the scientific community. However, during the last few decades, there has been an explosion of knowledge and the advent of digital age. We can access the publications of competitors with just a "click". The evaluation parameters have evolved a lot and are based on impact factors, h-index and citations. There is a general feeling that the scientific community is under a lot of pressure for fulfilling the criteria for upward growth and even retention of the positions held. The noble profession of scientific research and academics has been marred by the temptation to falsify and fabricate data, plagiarism and other unethical practices. Broadly speaking, the breach of ethics involves: plagiarism, falsification of data, redundant (duplicate) publication, drawing far-fetched conclusions without hard data, for early publicity, gift authorship (receiving as well as giving), not giving sufficient attention and consideration to scholars and post-docs as per the norms, self promotion at the cost of team-members, treating colleagues (overall all juniors) in a feudal way and Machiavellianism (cunningness and duplicity in general conduct and push to positions of power and pelf). Misconduct in Indian academics and science is also under a lot of focus. It is important and urgent that science, engineering, and health departments and institutions in our country have in place systems for education and training in pursuit of science with ethics by sound and professional courses in Responsible Conduct of Research. All research and academic institution must have the Office of Ethics for information, guidelines, training and professional oversight of conduct of research with the ethos and ethics of research.

15.
ACS Appl Mater Interfaces ; 7(6): 3708-16, 2015 Feb 18.
Article in English | MEDLINE | ID: mdl-25625695

ABSTRACT

Hexagonal boron nitride (h-BN), an isoelectric analogous to graphene multilayer, can easily shear at the contact interfaces and exhibits excellent mechanical strength, higher thermal stability, and resistance toward oxidation, which makes it a promising material for potential lubricant applications. However, the poor dispersibility of h-BN in lube base oil has been a major obstacle. Herein, h-BN powder was exfoliated into h-BN nanoplatelets (h-BNNPs), and then long alkyl chains were chemically grafted, targeting the basal plane defect and edge sites of h-BNNPs. The chemical and structural features of octadecyltriethoxysilane-functionalized h-BNNPs (h-BNNPs-ODTES) were studied by FTIR, XPS, XRD, HRTEM, and TGA analyses. The h-BNNPs-ODTES exhibit long-term dispersion stability in synthetic polyol ester lube base oil because of van der Waals interaction between the octadecyl chains of h-BNNPs-ODTES and alkyl functionalities of polyol ester. Micro- and macrotribology results showed that h-BNNPs-ODTES, as an additive to synthetic polyol ester, significantly reduced both the friction and wear of steel disks. Elemental mapping of the worn area explicitly demonstrates the transfer of h-BNNPs-ODTES on the contact interfaces. Furthermore, insight into the lubrication mechanism for reduction in both friction and wear is deduced based on the experimental results.

16.
Toxicon ; 81: 1-12, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24472344

ABSTRACT

The hepatoprotective effect of freeze-dried methanolic leaf extract of Ginkgo biloba was evaluated against lantadenes-induced hepatic damage in guinea pigs. The reversed-phase HPLC analysis of lantadenes confirmed the presence of 72.82% of lantadene A. UPLC-ESI-MS analysis showed the presence of ginkgolide B, C, bilobalide and traces of ginkgolide A and J in G. biloba extract. The concentration of ginkgolide B in the sample was found as 0.29%. The elevated levels of serum alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase due to lantadenes were significantly restored towards normal values by G. biloba extract in a dose-dependent manner. The effects of lantadenes and G. biloba extract on lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase were assayed in liver homogenates to evaluate the antioxidant activity. G. biloba extract in a dose-dependent manner produced significant decrease in lantadenes-induced increased levels of LPO. The lantadene-induced decreased levels of SOD, GSH and catalase were elevated by G. biloba extract. The findings of biochemical and antioxidant enzyme levels were supported by gross and histopathological observations. Moreover, liver sections of G. biloba group also showed a marked decrease in apoptosis in comparison to lantadenes group. This study suggested that G. biloba could be used as a promising hepatoprotectant against lantadenes-induced hepatic damage. Future studies are needed to elucidate the precise mechanism of hepatoprotection for practical application.


Subject(s)
Chemical and Drug Induced Liver Injury/prevention & control , Ginkgo biloba/chemistry , Liver/drug effects , Plant Extracts/pharmacology , Protective Agents/pharmacology , Animals , Apoptosis/drug effects , Catalase/metabolism , Glutathione/metabolism , Guinea Pigs , Lipid Peroxidation/drug effects , Oleanolic Acid/analogs & derivatives , Oxidative Stress/drug effects , Plant Extracts/chemistry , Superoxide Dismutase/metabolism , Toxins, Biological
17.
Rev Environ Contam Toxicol ; 224: 53-95, 2013.
Article in English | MEDLINE | ID: mdl-23232919

ABSTRACT

In this review, we address the major aspects of enzootic bovine hematuria and have placed special emphasis on describing the etiology, human health implications, and advanced molecular diagnosis of the disease.Enzootic bovine hematuria (EBH) is a bovine disease characterized by the intermittent presence of blood in the urine and is caused by malignant lesions in the urinary bladder. This incurable disease is a serious malady in several countries across many continents. Accurate early-stage diagnosis of the disease is possible by applying advanced molecular techniques, e.g., detection of genetic mutations in the urine of cows from endemic areas. Use of such diagnostic approaches may help create an effective therapy against the disease.There is a consensus that EBH is caused primarily by animals consuming bracken fern (P. aquilinum) as they graze. The putative carcinogen in bracken is ptaquiloside(PT), a glycoside. However, other bracken constituents like quercetin, isoquercetin,ptesculentoside, caudatoside, astragalin, and tannins may also be carcinogenic.Studies are needed to identify the role of other metabolites in inducing urinary bladder carcinogenesis.The bovine papilloma virus is also thought to be an associated etiology in causing EBH in cattle. There is growing alarm that these fern toxins and their metabolites reach and contaminate the soil and water environment and that the carcinogen (PT)is transmitted via cow's milk to the human food chain, where it may now pose a threat to human health. An increased incidence of gastric and esophageal cancer has been recorded in humans consuming bracken ferns, and among those living for long periods in areas infested with bracken ferns.Although preliminary therapeutic vaccine trials with inactivated BPV-2 against EBH have been performed, further work is needed to standardize and validate vaccine doses for animals.


Subject(s)
Cattle Diseases/etiology , Hematuria/veterinary , Indans/toxicity , Plant Poisoning/veterinary , Pteridium/poisoning , Sesquiterpenes/toxicity , Animals , Bovine papillomavirus 1/pathogenicity , Cattle , Cattle Diseases/diagnosis , Cattle Diseases/virology , Disease Models, Animal , Environmental Pollutants/poisoning , Hematuria/diagnosis , Hematuria/virology , Humans
18.
Curr Treat Options Cardiovasc Med ; 14(6): 652-64, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22983661

ABSTRACT

OPINION STATEMENT: Cardiac sarcoidosis can be life threatening if not promptly diagnosed and treated appropriately and aggressively. The diagnosis of myocardial disease is often difficult and circumstantial because there are no reliable diagnostic tests. Except for the finding of noncaseating granulomas on endomyocardial biopsy, most tests are limited and nonspecific. Therefore, the decision of initiating treatment is based on the patient's symptoms and the course of the disease, rather than on the presence of histologic confirmation. The goal of therapy is to prevent irreversible cardiomyopathy and to thwart the progression to heart transplantation. The mainstay of treatment is corticosteroids, although there are no large randomized trials analyzing corticosteroid use. The combination with other immunosuppressant agents, such as Methotrexate and Azathioprine, is initiated on the patient's failing or experiencing severe side effects from corticosteroids. While there are small studies proving the efficacy of tumor necrosis factor-inhibitors in cardiac sarcoidosis, more experience with these agents is needed. Catheter ablation or placement of implantable devices is indicated prophylactically in patients with severe ventricular tachyarrhythmias. Heart transplantation should be considered in patients with severe heart failure refractory to medical therapy. This article focuses on the current diagnostic tests and treatment recommendations for cardiac sarcoidosis.

19.
Curr Opin Pulm Med ; 18(5): 493-8, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22828211

ABSTRACT

PURPOSE OF REVIEW: Necrotizing sarcoid granulomatosis (NSG) is rare. Its various clinical and histological presentations are ambiguous and confusing. Although sometimes limited only to the lungs, other organ systems can be involved. The disease affects primarily women in their late forties but has been documented in children. RECENT FINDINGS: There are two schools of thought regarding the taxonomical position of NSG. Some believe that it is an independent entity, whereas others argue that it is just another manifestation of sarcoidosis. This article will review the available, current and evidence-based information about clinical and basic science aspects of NSG. SUMMARY: Diagnosis of NSG is perplexing; its pathogenesis is a dilemma. The disease is frequently confused with other processes including malignancy, Wegener's granulomatosis, hypersensitivity pneumonitis, sarcoidosis and lymphoid granulomatosis. Its symptoms are nonspecific and a histology finding of necrotizing granuloma has many causes. Although no specific management tool or strategies are advocated, steroids, surgical resection of localized disease or sometimes watchful waiting are recommended.


Subject(s)
Granuloma/epidemiology , Necrosis/epidemiology , Sarcoidosis/epidemiology , Comorbidity , Diagnosis, Differential , Disease Management , Granuloma/diagnosis , Granuloma/therapy , Humans , Necrosis/diagnosis , Necrosis/therapy , Sarcoidosis/diagnosis , Sarcoidosis/therapy , Watchful Waiting
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