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1.
Crit Rev Biotechnol ; : 1-31, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38915217

RESUMO

Microscopic plastic (microplastic) pollutants threaten the earth's biodiversity and ecosystems. As a result of the progressive fragmentation of oversized plastic containers and products or manufacturing in small sizes, microplastics (particles of a diameter of 5 mm with no lower limit) are used in medicines, personal care products, and industry. The incidence of microplastics is found everywhere in the air, marine waters, land, and even food that humans and animals consume. One of the greatest concerns is the permanent damage that is created by plastic waste to our fragile ecosystem. The impossibility of the complete removal of all microplastic contamination from the oceans is one of the principal tasks of our governing body, research scientists, and individuals. Implementing the necessary measures to reduce the levels of plastic consumption is the only way to protect our environment. Cutting off the plastic flow is the key remedy to reducing waste and pollution, and such an approach could show immense significance. This review offers a comprehensive exploration of the various aspects of microplastics, encompassing their composition, types, properties, origins, health risks, and environmental impacts. Furthermore, it delves into strategies for comprehending the dynamics of microplastics within oceanic ecosystems, with a focus on averting their integration into every tier of the food chain.

2.
Pediatr Res ; 81(4): 654-662, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28002390

RESUMO

BACKGROUND: Therapeutic hypothermia (HT) is the only intervention that improves outcomes in neonatal hypoxic-ischemic encephalopathy (HIE). However, the multifactorial mechanisms by which HT impacts HIE are incompletely understood. The complement system plays a major role in the pathogenesis of ischemia-reperfusion injuries such as HIE. We have previously demonstrated that HT modulates complement activity in vitro. METHODS: Term equivalent rat pups were subjected to unilateral carotid ligation followed by hypoxia (8% O2) for 45 min to simulate HIE. A subset of animals was subjected to HT (31-32°C for 6 h). Plasma and brain levels of C3a and C5a were measured. Receptors for C3a (C3aR) and C5a (C5aR) along with C1q, C3, and C9 were characterized in neurons, astrocytes, and microglia. RESULTS: We found that HT increased systemic expression of C3a and decreased expression of C5a after HIE. In the brain, C3aR and C5aR are predominantly expressed on microglia after HIE. HT increased local expression of C3aR and decreased expression on C5aR after HIE. Furthermore, HT decreased local expression of C1q, C3-products, and C9 in the brain. CONCLUSION: HT is associated with significant alteration of complement effectors and their cognate receptors. Complement modulation may improve outcomes in neonatal HIE.


Assuntos
Encefalopatias/sangue , Complemento C3a/análise , Complemento C5a/análise , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/sangue , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Encéfalo/patologia , Encefalopatias/terapia , Hipóxia , Hipóxia-Isquemia Encefálica/terapia , Microglia/metabolismo , Neurônios/metabolismo , Ratos , Ratos Wistar , Traumatismo por Reperfusão , Temperatura , Fatores de Tempo
3.
Transfusion ; 56(8): 2133-45, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27282513

RESUMO

BACKGROUND: Acute hemolytic transfusion reactions have a broad clinical presentation from mild and transitory signs and symptoms to shock, disseminated intravascular coagulation, renal failure, and death. We have recently developed a rat model of acute intravascular hemolysis showing that the classical complement pathway mediates antibody-dependent hemolysis. The objective of this study was to evaluate the role of the classical pathway inhibitor peptide inhibitor of complement C1 (PIC1) in this animal model. STUDY DESIGN AND METHODS: Male Wistar rats received a 15% transfusion of human red blood cells (RBCs) and blood was isolated from the animals up to 120 minutes. Animals received PIC1 either 2 minutes before or 0.5 minutes after transfusion. Sham-, vehicle-, and cobra venom factor (CVF)-treated animals were used as control groups with a subset of rats also receiving an equivalent dose of intravenous immunoglobulin (IVIG) before transfusion. Blood was analyzed for transfused RBC survival by flow cytometry and free hemoglobin (Hb) in isolated plasma by spectrophotometry. RESULTS: Vehicle-treated rats showed decreased human RBC survival and increased free Hb as expected. Rats receiving PIC1 before transfusion showed increased human RBC survival and decreased Hb similar to CVF-treated rats. Notably, rats receiving PIC1 after initiation of transfusion showed similar decreases in hemolysis as animals receiving PIC1 before transfusion. Compared to IVIG and saline controls, PIC1-treated animals demonstrated decreased hemolysis and protection from acute kidney injury. CONCLUSIONS: These results demonstrate that PIC1 has efficacy in an animal model of acute intravascular hemolysis in both prevention and rescue scenarios.


Assuntos
Complemento C1/antagonistas & inibidores , Hemólise/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Incompatibilidade de Grupos Sanguíneos/tratamento farmacológico , Contagem de Eritrócitos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Hemoglobinas/metabolismo , Humanos , Masculino , Peptídeos/uso terapêutico , Ratos , Ratos Wistar , Reação Transfusional/tratamento farmacológico
4.
Transfusion ; 54(11): 2892-900, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24806146

RESUMO

BACKGROUND: Prevention of acute hemolytic transfusion reactions is a worldwide concern. The objective of this study was to develop a simple rat model of complement-mediated acute intravascular hemolysis. STUDY DESIGN AND METHODS: Human AB red blood cells (RBCs) were incubated with complement-sufficient or complement-deficient Wistar rat serum (WRS) in the presence and absence of human RBC antibody in vitro to elucidate the mechanism of hemolysis. To study the role of complement in acute intravascular hemolysis in vivo, Wistar rats were treated either with or without cobra venom factor (CVF) to deplete complement activity. Human AB RBCs were then injected into both groups of rats, followed by serial blood draws up to 2 hours. Venous blood clearance and lysis of transfused RBCs at each time point were measured by flow cytometry and spectrophotometry. RBC sequestration was determined in the liver, spleen, and kidney by immunohistochemistry. RESULTS: In vitro incubation of human RBCs with WRS demonstrated that RBC lysis was mediated via the classical complement pathway and that hemolysis was antibody dependent. Transfusion of human RBCs into rats showed significantly less hemolysis in the CVF group versus untreated group. RBC sequestration in the spleen and liver 2 hours posttransfusion were not quantitatively different between the two groups. CONCLUSIONS: Given the much higher degree of similarity for rat and human complement compared to mice, this simple rat model is ideal for testing novel inhibitors of classical pathway activation for the prevention and treatment of acute intravascular hemolysis.


Assuntos
Proteínas do Sistema Complemento , Transfusão de Eritrócitos/efeitos adversos , Eritrócitos/metabolismo , Hemólise , Fígado/metabolismo , Baço/metabolismo , Doença Aguda , Animais , Inativadores do Complemento/farmacologia , Via Clássica do Complemento/efeitos dos fármacos , Modelos Animais de Doenças , Venenos Elapídicos/farmacologia , Eritrócitos/patologia , Humanos , Fígado/patologia , Camundongos , Ratos , Ratos Wistar , Especificidade da Espécie , Baço/patologia
5.
Am J Physiol Cell Physiol ; 305(9): C919-30, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23864605

RESUMO

KCNH2 encodes Kv11.1 and underlies the rapidly activating delayed rectifier K(+) current (IKr) in the heart. Loss-of-function KCNH2 mutations cause the type 2 long QT syndrome (LQT2), and most LQT2-linked missense mutations inhibit the trafficking of Kv11.1 channels. Drugs that bind to Kv11.1 and block IKr (e.g., E-4031) can act as pharmacological chaperones to increase the trafficking and functional expression for most LQT2 channels (pharmacological correction). We previously showed that LQT2 channels are selectively stored in a microtubule-dependent compartment within the endoplasmic reticulum (ER). We tested the hypothesis that pharmacological correction promotes the trafficking of LQT2 channels stored in this compartment. Confocal analyses of cells expressing the trafficking-deficient LQT2 channel G601S showed that the microtubule-dependent ER compartment is the transitional ER. Experiments with E-4031 and the protein synthesis inhibitor cycloheximide suggested that pharmacological correction promotes the trafficking of G601S stored in this compartment. Treating cells in E-4031 or ranolazine (a drug that blocks IKr and has a short half-life) for 30 min was sufficient to cause pharmacological correction. Moreover, the increased functional expression of G601S persisted 4-5 h after drug washout. Coexpression studies with a dominant-negative form of Rab11B, a small GTPase that regulates Kv11.1 trafficking, prevented the pharmacological correction of G601S trafficking from the transitional ER. These data suggest that pharmacological correction quickly increases the trafficking of LQT2 channels stored in the transitional ER via a Rab11B-dependent pathway, and we conclude that the pharmacological chaperone activity of drugs like ranolazine might have therapeutic potential.


Assuntos
Retículo Endoplasmático/genética , Canais de Potássio Éter-A-Go-Go/genética , Síndrome do QT Longo/genética , Mutação de Sentido Incorreto/genética , Adolescente , Adulto , Idoso , Antiarrítmicos/farmacologia , Canal de Potássio ERG1 , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Canais de Potássio Éter-A-Go-Go/metabolismo , Feminino , Células HEK293 , Humanos , Síndrome do QT Longo/metabolismo , Masculino , Pessoa de Meia-Idade , Piperidinas/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Piridinas/farmacologia , Adulto Jovem
6.
Am J Case Rep ; 24: e939803, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37231631

RESUMO

BACKGROUND RLS-0071 is a dual-targeting peptide developed for the regulation of humoral and cellular inflammation via inhibition of neutrophil effectors, including myeloperoxidase and neutrophil extracellular trap formation (NETosis). The safety, pharmacokinetics, and pharmacodynamics of single and multiple doses of RLS-0071 were evaluated in a first-in-human clinical trial in healthy volunteers. Myeloperoxidase is the major peroxidase enzyme present in neutrophilic granules and contributes to cellular inflammation. Extracellular myeloperoxidase has been associated with chronic inflammation in a variety of diseases, including atherosclerosis. RLS-0071 has previously been shown to inhibit extracellular myeloperoxidase function both in vitro and in vivo in animal disease models. CASE REPORT Healthy subjects participating in the RLS-0071-101 study were screened for baseline myeloperoxidase level, leading to the identification of a 21-year-old woman with elevated baseline levels. After randomization, the subject received 9 intravenous infusions of 10 mg/kg RLS-0071. The subject tolerated the peptide infusions well with no adverse changes in vital signs, significantly abnormal clinical laboratory results, or severe adverse events. Analysis of this subject's myeloperoxidase plasma concentrations demonstrated that her myeloperoxidase levels decreased by 43% and myeloperoxidase activity levels decreased 49% after infusions of RLS-0071. The reduction in the patient's plasma myeloperoxidase levels demonstrated a partial return to baseline levels 24 hours after cessation of dosing. There were no other clinically meaningful safety observations for this subject. CONCLUSIONS This observation suggests RLS-0071 has the therapeutic potential to moderate plasma myeloperoxidase levels and activity and modulate diseases in which myeloperoxidase contributes to pathogenesis.


Assuntos
Inflamação , Peroxidase , Feminino , Animais , Humanos , Adulto Jovem , Adulto , Infusões Intravenosas
7.
ACS Chem Neurosci ; 14(24): 4383-4394, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38050970

RESUMO

Parkinson's disease (PD) is characterized by extrapyramidal motor disturbances and nonmotor cognitive impairments which impact activities of daily living. Although the etiology of PD is still obscure, autopsy reports suggest that oxidative stress (OS) is one of the important factors in the pathophysiology of PD. In the current study, we have investigated the impact of OS in PD by measuring the antioxidant glutathione (GSH) levels from the substantia nigra (SN), left hippocampus (LH) and neurotransmitter γ-amino butyric acid (GABA) levels from SN region. Concomitant quantitative susceptibility mapping (QSM) from SN and LH was also acquired from thirty-eight PD patients and 30 age-matched healthy controls (HC). Glutathione levels in the SN region decreased significantly and susceptibility increased significantly in PD compared to HC. Nonsignificant depletion of GABA was observed in the SN region. GSH levels in the LH region were depleted significantly, but LH susceptibility did not alter in the PD cohort compared to HC. Neuropsychological and physical assessment demonstrated significant impairment of cognitive functioning in PD patients compared to HC. GSH depletion was negatively correlated to motor function performance. Multivariate receiver operating characteristic (ROC) curve analysis on the combined effect of GSH, GABA, and susceptibility in the SN region yielded an improved diagnostic accuracy of 86.1% compared to individual diagnostic accuracy based on GSH (65.8%), GABA (57.5%), and susceptibility (69.6%). This is the first comprehensive report in PD demonstrating significant GSH depletion as well as concomitant iron enhancement in the SN region.


Assuntos
Doença de Parkinson , Humanos , Atividades Cotidianas , Imageamento por Ressonância Magnética/métodos , Substância Negra , Glutationa , Espectroscopia de Ressonância Magnética , Ácido gama-Aminobutírico
8.
Am J Physiol Cell Physiol ; 301(1): C75-85, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21490315

RESUMO

The human ether-a-go-go related gene (hERG) encodes the voltage-gated K(+) channel that underlies the rapidly activating delayed-rectifier current in cardiac myocytes. hERG is synthesized in the endoplasmic reticulum (ER) as an "immature" N-linked glycoprotein and is terminally glycosylated in the Golgi apparatus. Most hERG missense mutations linked to long QT syndrome type 2 (LQT2) reduce the terminal glycosylation and functional expression. We tested the hypothesis that a distinct pre-Golgi compartment negatively regulates the trafficking of some LQT2 mutations to the Golgi apparatus. We found that treating cells in nocodazole, a microtubule depolymerizing agent, altered the subcellular localization, functional expression, and glycosylation of the LQT2 mutation G601S-hERG differently from wild-type hERG (WT-hERG). G601S-hERG quickly redistributed to peripheral compartments that partially colocalized with KDEL (Lys-Asp-Glu-Leu) chaperones but not calnexin, Sec31, or the ER golgi intermediate compartment (ERGIC). Treating cells in E-4031, a drug that increases the functional expression of G601S-hERG, prevented the accumulation of G601S-hERG to the peripheral compartments and increased G601S-hERG colocalization with the ERGIC. Coexpressing the temperature-sensitive mutant G protein from vesicular stomatitis virus, a mutant N-linked glycoprotein that is retained in the ER, showed it was not restricted to the same peripheral compartments as G601S-hERG at nonpermissive temperatures. We conclude that the trafficking of G601S-hERG is negatively regulated by a microtubule-dependent compartment within the ER. Identifying mechanisms that prevent the sorting or promote the release of LQT2 channels from this compartment may represent a novel therapeutic strategy for LQT2.


Assuntos
Retículo Endoplasmático/metabolismo , Canais de Potássio Éter-A-Go-Go/metabolismo , Síndrome do QT Longo/genética , Microtúbulos/metabolismo , Antiarrítmicos/farmacologia , Western Blotting , Canais de Potássio Éter-A-Go-Go/biossíntese , Canais de Potássio Éter-A-Go-Go/genética , Imunofluorescência , Glicosilação , Complexo de Golgi/metabolismo , Proteínas de Fluorescência Verde , Células HEK293 , Humanos , Síndrome do QT Longo/metabolismo , Microtúbulos/efeitos dos fármacos , Mutação , Miócitos Cardíacos/metabolismo , Nocodazol/farmacologia , Técnicas de Patch-Clamp , Piperidinas/farmacologia , Transporte Proteico , Piridinas/farmacologia , Moduladores de Tubulina/farmacologia
9.
Diabetologia ; 54(12): 3022-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21959957

RESUMO

AIMS/HYPOTHESIS: This study reports the results of the first phase of a national study to determine the prevalence of diabetes and prediabetes (impaired fasting glucose and/or impaired glucose tolerance) in India. METHODS: A total of 363 primary sampling units (188 urban, 175 rural), in three states (Tamilnadu, Maharashtra and Jharkhand) and one union territory (Chandigarh) of India were sampled using a stratified multistage sampling design to survey individuals aged ≥ 20 years. The prevalence rates of diabetes and prediabetes were assessed by measurement of fasting and 2 h post glucose load capillary blood glucose. RESULTS: Of the 16,607 individuals selected for the study, 14,277 (86%) participated, of whom 13,055 gave blood samples. The weighted prevalence of diabetes (both known and newly diagnosed) was 10.4% in Tamilnadu, 8.4% in Maharashtra, 5.3% in Jharkhand, and 13.6% in Chandigarh. The prevalences of prediabetes (impaired fasting glucose and/or impaired glucose tolerance) were 8.3%, 12.8%, 8.1% and 14.6% respectively. Multiple logistic regression analysis showed that age, male sex, family history of diabetes, urban residence, abdominal obesity, generalised obesity, hypertension and income status were significantly associated with diabetes. Significant risk factors for prediabetes were age, family history of diabetes, abdominal obesity, hypertension and income status. CONCLUSIONS/INTERPRETATIONS: We estimate that, in 2011, Maharashtra will have 6 million individuals with diabetes and 9.2 million with prediabetes, Tamilnadu will have 4.8 million with diabetes and 3.9 million with prediabetes, Jharkhand will have 0.96 million with diabetes and 1.5 million with prediabetes, and Chandigarh will have 0.12 million with diabetes and 0.13 million with prediabetes. Projections for the whole of India would be 62.4 million people with diabetes and 77.2 million people with prediabetes.


Assuntos
Diabetes Mellitus/epidemiologia , Inquéritos Epidemiológicos/estatística & dados numéricos , Estado Pré-Diabético/epidemiologia , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adulto , Idoso , Glicemia/análise , Comorbidade , Estudos Transversais , Feminino , Humanos , Hipertensão/epidemiologia , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/epidemiologia , Prevalência , Fatores Sexuais , Adulto Jovem
10.
J Commun Dis ; 43(4): 285-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23781647

RESUMO

We report a case of Salmonella meningitis due to Salmonella serotype infantis. The organism was isolated from the blood and CSF of a ten month old baby. The baby died due to fulminant meningitis with septicemia. This case has been reported for its rarity.


Assuntos
Bacteriemia/complicações , Meningites Bacterianas/complicações , Infecções por Salmonella/complicações , Evolução Fatal , Humanos , Lactente , Masculino
11.
Mater Today Proc ; 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33520674

RESUMO

The epic Covid sickness 2019 (COVID-19) has turned into the significant danger to humankind in year 2020. The pandemic COVID-19 flare-up has influenced more than 2.7 million individuals and caused around 187 thousand fatalities worldwide [1] inside scarcely any months of its first appearance in Wuhan city of China and the number is developing quickly in various pieces of world. As researcher everywhere on the world are battling to discover the fix and treatment for COVID-19, the urgent advance fighting against COVID-19 is the screening of immense number of associated cases for disconnection and isolate with the patients. One of the key methodologies in screening of COVID-19 can be chest radiological imaging. The early investigations on the patients influenced by COVID-19 shows the attributes variations from the norm in chest radiography pictures. This introduced a chance to utilize distinctive counterfeit clever (AI) frameworks dependent on profound picking up utilizing chest radiology pictures for the recognition of COVID-19 and numerous such framework were proposed indicating promising outcomes. In this paper, we proposed a profound learning based convolution neural organization to characterize COVID-19, Pneumonia and Normal cases from chest radiology pictures. The proposed convolution neural organization (CNN) grouping model had the option to accomplish exactness of 94.85% on test dataset. The trial was completed utilizing the subset of information accessible in GitHub and Kaggle.

12.
Pediatrics ; 140(3)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28768853

RESUMO

BACKGROUND: Plain children often have lower immunization rates than non-Plain children. Penn State Health Children's Hospital is a tertiary medical center with large nearby Plain (Amish and Mennonite) communities. We sought to describe the characteristics of children hospitalized with vaccine-preventable diseases (VPDs). We hypothesized that Amish children would have a higher risk of VPDs than non-Amish children. METHODS: International Classification of Diseases, Ninth Revision codes were used to identify patients <18 years diagnosed with a VPD from January 1, 2005, to December 31, 2015, at Penn State Children's Hospital. Demographic information, immunization status, and outcomes were obtained from medical records. By using the number of children in our primary service area, we calculated the risk of VPD requiring hospitalization for Amish and non-Amish children. We assessed the relationship between Plain affiliation and vaccination status by using the Pearson correlation coefficient. RESULTS: There were 215 children with 221 VPDs. Most occurred in non-Plain children: 179 of 221 (81%). Except for pneumococcal infections, VPD occurred mostly in unvaccinated or immunocompromised children, regardless of Plain affiliation. There were 15 Haemophilus influenzae type b and 5 tetanus infections that occurred in children with an unvaccinated or unknown vaccination status. The risk of a VPD requiring hospitalization was greater for Amish than for non-Plain children (risk ratio: 2.67 [95% confidence interval: 1.87-3.82]). There was a strong correlation between Plain affiliation and lack of vaccination (r = -0.63, P < .01). CONCLUSIONS: Amish children had an increased risk of a VPD requiring hospitalization than non-Plain children. With the exception of those with pneumococcal disease, most vaccinated children hospitalized with a VPD were immunocompromised.


Assuntos
Doenças Transmissíveis/epidemiologia , Hospitalização/estatística & dados numéricos , Vacinação/estatística & dados numéricos , Amish , Criança , Pré-Escolar , Doenças Transmissíveis/imunologia , Feminino , Humanos , Programas de Imunização , Lactente , Masculino
13.
Biomed Tech (Berl) ; 61(4): 443-53, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27060730

RESUMO

In view of predicting bright lesions such as hard exudates, cotton wool spots, and drusen in retinal images, three different segmentation techniques have been proposed and their effectiveness is compared with existing segmentation techniques. The benchmark images with annotations present in the structured analysis of the retina (STARE) database is considered for testing the proposed techniques. The proposed segmentation techniques such as region growing (RG), region growing with background correction (RGWBC), and adaptive region growing with background correction (ARGWBC) have been used, and the effectiveness of the algorithms is compared with existing fuzzy-based techniques. Images of eight categories of various annotations and 10 images in each category have been used to test the consistency of the proposed algorithms. Among the proposed techniques, ARGWBC has been identified to be the best method for segmenting the bright lesions based on its sensitivity, specificity, and accuracy. Fifteen different features are extracted from retinal images for the purpose of identification and classification of bright lesions. Feedforward backpropagation neural network (FFBPNN) and pattern recognition neural network (PRNN) are used for the classification of normal/abnormal images. Probabilistic neural network (PNN), radial basis exact fit (RBE), radial basis fewer neurons (RB), and FFBPNN are used for further bright lesion classification and achieve 100% accuracy.


Assuntos
Retinopatia Diabética/patologia , Exsudatos e Transudatos/citologia , Interpretação de Imagem Assistida por Computador/métodos , Retina/patologia , Algoritmos , Bases de Dados Factuais , Humanos , Sensibilidade e Especificidade
14.
Dalton Trans ; 44(18): 8718-28, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25856295

RESUMO

New stannate based displaced pyrochlore-type red phosphors, Ca(3-x)Sn3Nb2O14:xEu(3+), were prepared via a conventional solid state method. The influence of partial occupancy of Sn in both A and B sites of the pyrochlore-type oxides on the photoluminescence properties was studied using powder X-ray diffraction, FT-Raman, transmission electron microscopy, scanning electron microscopy with energy dispersive spectrometry, UV-visible absorption spectroscopy, and photoluminescence excitation and emission spectra with lifetime measurements. The structural analysis establishes that these oxides belong to a cubic displaced pyrochlore type structure with a space group Fd3̄m. These phosphors exhibit strong absorptions at near UV and blue wavelength regions and emit intense multiband emissions due to Eu(3+ 5)D0-(7)F(0, 1, 2) transitions. The absence of characteristic MD transition splitting points out that local cation disorder exists in this type of displaced pyrochlores, reducing the D(3d) inversion symmetry, which is not evidenced by such disorder in the X-ray diffraction analysis. The unusual forbidden intense sharp (5)D0-(7)F0 transition indicates single site occupancy of Eu(3+) with a narrower range of bonding environment, preventing the cluster formation. This is supported by the stable (5)D0 lifetime with Eu(3+) concentration. The Judd-Ofelt intensity parameter assessment corroborates these results. The CIE color coordinates of these phosphors were found to be (0.60, 0.40), which are close to the NTSC standard values (0.67, 0.33) for a potential red phosphor.

15.
Mol Immunol ; 67(2 Pt B): 575-83, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26256795

RESUMO

BACKGROUND: Staphylococcus aureus peritonitis is a serious complication of Chronic Peritoneal Dialysis (CPD) and associated with a higher risk for severe and recurrent infections compared with other bacteria. We have previously shown that complement-mediated effectors essential for optimal opsonophagocytosis of S. aureus are inhibited by high glucose concentrations. Since most commonly used peritoneal dialysis (PD) fluids are glucose-based, we hypothesized that glucose-based PD fluids likely inhibit complement host defenses against S. aureus. METHODS: Commercially available PD fluids were tested: glucose-based (Dianeal), Dianeal supplemented with amino acids, icodextrin-based (Extraneal) and amino acid-based (Nutrineal). Control PD fluid was generated to simulate Dianeal excluding the glucose. Three commercially available glucose concentrations were tested: Dianeal 1.5% (15 gm/1000 ml), Dianeal 2.5% (25 gm/1000 ml) and Dianeal 4.25% (42.5 gm/1000 ml). Complement effectors against S. aureus were analyzed including opsonization with C3-fragments, anaphylatoxin generation, and phagocytosis efficiency. We also evaluated clinical strains, including MRSA strains, and specific complement activation pathways. RESULTS: Glucose-based PD fluids inhibited complement opsonization of S. aureus (≥7-fold reduction) and inhibited S. aureus-induced generation of anaphylatoxins C3a and C5a (>10-fold reduction) compared to non-glucose based PD fluids. Dianeal 1.5%, 2.5% and 4.25%, all similarly inhibited C3-mediated opsonization. Glucose-based PD fluids showed a ≥4-fold reduction in opsonization of clinical strains of S.aureus, including MRSA strains. Decreased opsonization of S.aureus in the glucose-based PD fluid compared with non-glucose based fluids correlated with decreased phagocytosis by neutrophils. CONCLUSION: Complement-mediated opsonophagocytosis of S. aureus and anaphylatoxin generation were severely inhibited in glucose-based PD fluids compared with non-glucose-based PD fluids. By inhibiting complement host defenses, glucose-based PD fluids may increase the risk of and severity of S. aureus peritonitis for CPD patients using these fluids.


Assuntos
Soluções para Diálise/farmacologia , Glucose/farmacologia , Imunidade Inata/efeitos dos fármacos , Diálise Renal , Staphylococcus aureus/imunologia , Anafilatoxinas/imunologia , Complemento C3/imunologia , Via Alternativa do Complemento/efeitos dos fármacos , Humanos , Proteínas Opsonizantes/metabolismo , Fagocitose/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
16.
PLoS One ; 10(7): e0132446, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26196285

RESUMO

The complement system has been increasingly recognized to play a pivotal role in a variety of inflammatory and autoimmune diseases. Consequently, therapeutic modulators of the classical, lectin and alternative pathways of the complement system are currently in pre-clinical and clinical development. Our laboratory has identified a peptide that specifically inhibits the classical and lectin pathways of complement and is referred to as Peptide Inhibitor of Complement C1 (PIC1). In this study, we determined that the lead PIC1 variant demonstrates a salt-dependent binding to C1q, the initiator molecule of the classical pathway. Additionally, this peptide bound to the lectin pathway initiator molecule MBL as well as the ficolins H, M and L, suggesting a common mechanism of PIC1 inhibitory activity occurs via binding to the collagen-like tails of these collectin molecules. We further analyzed the effect of arginine and glutamic acid residue substitution on the complement inhibitory activity of our lead derivative in a hemolytic assay and found that the original sequence demonstrated superior inhibitory activity. To improve upon the solubility of the lead derivative, a pegylated, water soluble variant was developed, structurally characterized and demonstrated to inhibit complement activation in mouse plasma, as well as rat, non-human primate and human serum in vitro. After intravenous injection in rats, the pegylated derivative inhibited complement activation in the blood by 90% after 30 seconds, demonstrating extremely rapid function. Additionally, no adverse toxicological effects were observed in limited testing. Together these results show that PIC1 rapidly inhibits classical complement activation in vitro and in vivo and is functional for a variety of animal species, suggesting its utility in animal models of classical complement-mediated diseases.


Assuntos
Ativação do Complemento/efeitos dos fármacos , Complemento C1q/imunologia , Peptídeos/química , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Humanos , Injeções , Lectinas/imunologia , Macaca fascicularis , Masculino , Lectina de Ligação a Manose/imunologia , Camundongos , Dados de Sequência Molecular , Peptídeos/administração & dosagem , Peptídeos/sangue , Ratos , Ratos Wistar , Ovinos , Ficolinas
17.
Dis Markers ; 20(6): 317-23, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15665392

RESUMO

Pseudomonas aeruginosa is one of the major causes of infections including the hospital acquired (Nosocomial) infections. Detection of them and their antibiotic resistance profile by conventional method takes about three days. Recently, DNA based diagnostic methods are being used for the identification of the pathogens. Hence we have tested a rapid and sensitive method using DNA sequences as markers for detecting the presence of three genes coding for the enzymes that inactivate the two most commonly used Anti-pseudomonadal drugs such as beta-lactam antibiotics (Penicillin, and its derivatives) and Aminoglycosides such as Gentamicin, Tobramycin, Amikacin, Streptomycin. The internal region of these genes were used for designing and synthesizing primers and these primers were used in Polymerase Chain Reaction (PCR) to screen for the presence of these genes in the clinical isolates and to label them non-radioactively with Biotin. They in turn were used to detect the presence of the antibiotic resistance genes in the clinical isolates by hybridization. The specificity (ratio of positive results obtained in both methods and the sensitivity (the minimum amount of sample DNA and the labeled probe required for the tests) were evaluated.


Assuntos
Aminoglicosídeos/metabolismo , Anti-Infecciosos/farmacologia , Biomarcadores , Infecção Hospitalar/diagnóstico , Farmacorresistência Bacteriana , Infecções por Pseudomonas/diagnóstico , Pseudomonas aeruginosa/metabolismo , beta-Lactamases/genética , Amicacina/farmacologia , Antibacterianos/farmacologia , Biotina/química , Southern Blotting , DNA/química , Primers do DNA/química , Relação Dose-Resposta a Droga , Eletroforese em Gel de Ágar , Gentamicinas/farmacologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Hibridização de Ácido Nucleico , Penicilinas/farmacologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos , Estreptomicina/farmacologia , Tobramicina/farmacologia
18.
Indian J Pathol Microbiol ; 46(3): 501-3, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15025324

RESUMO

During a one year study 2955 clinical specimens of pus, urine, wound swabs, blood cultures, discharges from fistula, peritoneal aspiration fluid, CSF and sputum were processed to find out the prevalence rate of enterococci. One hundred isolates (3.38%) of Enterococci were obtained which were speciated by conventional methods. The highest incidence was from isolates of urine (43%), pus (40%), wound swabs (11%), and the least incidence was noted in discharges from fistula (2%), blood cultures (2%) and peritoneal aspiration fluid (2%). 98% were Enterococci and among these 88% of the isolates were Enterococcus faecalis. Antibiogram of the isolates were done by Standard disc diffusion method and Vancomycin sensitivity was found to be 95%.


Assuntos
Enterococcus faecalis/isolamento & purificação , Infecções por Bactérias Gram-Positivas/microbiologia , Enterococcus faecalis/efeitos dos fármacos , Humanos , Índia , Testes de Sensibilidade Microbiana
19.
Case Rep Pediatr ; 2013: 153239, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24106631

RESUMO

Methicillin resistant Staphylococcus aureus (MRSA) is increasingly being described as a cause of acute sinusitis. We present a patient with acute MRSA sinusitis complicated by rapid intracranial extension, marginal vancomycin susceptibility (MIC = 2 mg/L), delayed drainage of intracranial abscess, and subsequent development of rifampin resistance. Given the relatively high risk of intracranial extension of severe acute bacterial sinusitis and high mortality associated with invasive MRSA infections, we suggest early surgical drainage of intracranial abscesses in these circumstances. We believe this is important given the limited intracranial penetration of currently available treatment options for MRSA, especially those with a vancomycin minimal inhibitory concentration (MIC) of ≥2 mg/L.

20.
Indian J Pathol Microbiol ; 52(2): 265-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19332936

RESUMO

Most of the Bartholin's gland abscesses have been thought to be caused by colonizing micro-organisms of the perineal region. We encountered an interesting case of acute Bartholins abscess caused by Streptococcus pneumoniae in a primigravida. The abscess was incised and drained. The patient was treated with Cefuroxime. This case is presented for its rarity.


Assuntos
Abscesso/microbiologia , Glândulas Vestibulares Maiores/microbiologia , Infecções Pneumocócicas/diagnóstico , Complicações Infecciosas na Gravidez , Streptococcus pneumoniae/isolamento & purificação , Abscesso/patologia , Adulto , Antibacterianos/uso terapêutico , Glândulas Vestibulares Maiores/patologia , Cefuroxima/uso terapêutico , Feminino , Humanos , Infecções Pneumocócicas/microbiologia , Gravidez , Adulto Jovem
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