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1.
Anal Chem ; 96(37): 14891-14901, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39215686

RESUMO

The destructive assay of bulk uranium and plutonium, a cornerstone for chemical quality control and nuclear material accounting of fuel matrices, mandates robust and precise methodologies. Despite ongoing research, simultaneous, matrix independent determination of U and Pu has eluded solution owing to inherent limitations in aqueous acid medium, viz., coexistence of multiple oxidation states, coupled electrochemical reactions, smaller potential window, and requirement for multistep sample preconditioning and tedious electrode modification. The present study addresses this challenge wherein non-aqueous methanesulfonic acid (MSA) served the dual role of solvent and analyte media with a bare glassy carbon (GC) electrode. Fuel matrices, viz., (U, Pu)C, (U, Pu)O2, PuO2, UO3, UO2, and U3O8, were quantitatively dissolved in biodegradable MSA, without using any additives. Redox speciation of the analytes, U and Pu, in MSA was probed by ultraviolet-visible spectrophotometry and electrometry, revealing the absence of electrocatalytic regeneration and stabilization of single oxidation state, viz., U(VI) and Pu(IV), along with relevant redox-energetic (electron transfer and reversibility) and kinetic data. Bidentate coordination of MSA with the U analyte was indicated by X-ray absorption spectroscopy studies and was corroborated by density functional theory-based investigations, providing the optimized structure, viz., [UO2(MSA)2] and [Pu(MSA)4], binding modes and energy, partial charges, and molecular orbital diagrams. Based on these insights, the feasibility of differential pulse voltammetry (DPV)-based assay method development for U and Pu separately and in different U/Pu ratios, representing assorted fuel matrices, was probed. Analytical figures of merit for both U and Pu (detection limit of ∼10-5 M, precision of ∼0.2%, accuracy of ∼0.2%, high sensitivity, repeatability, and non-influence of relevant interferences) were determined, method validated employing actual fuel samples, and compared with the established, multi-step biamperometry method. Hence, a universal, simultaneous U and Pu destructive assay method in non-aqueous MSA media based on DPV with a commercial GC electrode was demonstrated.

2.
Biotechnol Bioeng ; 121(1): 100-117, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37881101

RESUMO

Probiotic microorganisms have been used for therapeutic purposes for over a century, and recent advances in biotechnology and genetic engineering have opened up new possibilities for developing therapeutic approaches using indigenous probiotic microorganisms. Diseases are often related to metabolic and immunological factors, which play a critical role in their onset. With the help of advanced genetic tools, probiotics can be modified to produce or secrete important therapeutic peptides directly into mucosal sites, increasing their effectiveness. One potential approach to enhancing human health is through the use of designer probiotics, which possess immunogenic characteristics. These genetically engineered probiotics hold promise in providing novel therapeutic options. In addition to their immunogenic properties, designer probiotics can also be equipped with sensors and genetic circuits, enabling them to detect a range of diseases with remarkable precision. Such capabilities may significantly advance disease diagnosis and management. Furthermore, designer probiotics have the potential to be used in diagnostic applications, offering a less invasive and more cost-effective alternative to conventional diagnostic techniques. This review offers an overview of the different functional aspects of the designer probiotics and their effectiveness on different diseases and also, we have emphasized their limitations and future implications. A comprehensive understanding of these functional attributes may pave the way for new avenues of prevention and the development of effective therapies for a range of diseases.


Assuntos
Probióticos , Humanos , Probióticos/uso terapêutico , Probióticos/metabolismo , Engenharia Genética , Biotecnologia , Redes Reguladoras de Genes
3.
Angew Chem Int Ed Engl ; 63(29): e202405459, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38711309

RESUMO

The hydrogen evolution and nitrite reduction reactions are key to producing green hydrogen and ammonia. Antenna-reactor nanoparticles hold promise to improve the performances of these transformations under visible-light excitation, by combining plasmonic and catalytic materials. However, current materials involve compromising either on the catalytic activity or the plasmonic enhancement and also lack control of reaction selectivity. Here, we demonstrate that ultralow loadings and non-uniform surface segregation of the catalytic component optimize catalytic activity and selectivity under visible-light irradiation. Taking Pt-Au as an example we find that fine-tuning the Pt content produces a 6-fold increase in the hydrogen evolution compared to commercial Pt/C as well as a 6.5-fold increase in the nitrite reduction and a 2.5-fold increase in the selectivity for producing ammonia under visible light excitation relative to dark conditions. Density functional theory suggests that the catalytic reactions are accelerated by the intimate contact between nanoscale Pt-rich and Au-rich regions at the surface, which facilitates the formation of electron-rich hot-carrier puddles associated with the Pt-based active sites. The results provide exciting opportunities to design new materials with improved photocatalytic performance for sustainable energy applications.

4.
Phys Chem Chem Phys ; 24(7): 4415-4424, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35113109

RESUMO

The thin films of Ni and Bi are known to form NiBi3 and NiBi compounds spontaneously at the interface, which become superconducting below 4.2 K and show ferromagnetism either intrinsically or due to Ni impurities. Formation of NiBi3 and NiBi is a slow diffusion reaction, which means the local environment around Ni and Bi atoms may vary with time and temperature. In this report, we assess the feasibility of using X-ray Absorption Spectroscopy (XAS) as a tool to track the changes in local bonding environment in NiBi3 and NiBi. Thermal annealing at temperatures up to 500 °C was used to induce changes in the local environment in NiBi3 system. Consequent decomposition of NiBi3 into NiO and Bi has been tracked through changes in structural and magnetization behavior, which matched well with the findings of XAS. In addition, the magnetic hysteresis measurements indicated that NiO should be the dominant phase when NiBi3 is annealed at 500 °C. This was corroborated from XAS and was found to be >90%. The shift in K-edge of Ni in annealed samples was attributed to increasing charge state on Ni atom, which was ascertained by Bader charge analysis using Density Functional Theory (DFT). This study correlating macroscopic properties of NiBi3 with local bonding environment of the system indicates that XAS can be a very reliable tool for studying dynamics of diffusion in the NiBi3 system.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34534345

RESUMO

BACKGROUND: The non-transferrin bound catalytic iron moiety catalyses production of toxic reactive oxygen species and is associated with adverse outcomes. We hypothesized that serum catalytic iron (SCI) is associated with progression of chronic kidney disease (CKD). METHODS: Baseline samples of the Indian Chronic Kidney Disease participants with at least one follow up visit were tested for total iron, iron binding capacity, transferrin saturation, SCI, ferritin and hepcidin. SCI was measured using the bleomycin-detectable iron assay that detects biologically active iron. Association with the incidence of major kidney endpoints, (MAKE, a composite of kidney death, kidney failure or > 40% loss of eGFR) was examined using Cox proportional hazards model adjusted for sex and age. RESULTS: 2002 subjects (49.9 ± 11.6 years, 68.1% males, baseline eGFR 41.01 ml/min/1.73m2) were enrolled. After a median follow up of 12.6 (12.2, 16.7) months, the composite MAKE occurred in 280 (14%). After adjusting for age and sex, increase from 25th to 75th percentile in SCI, transferrin saturation, ferritin and hepcidin were associated with 78% (43-122%), 34% (10-62%), 57% (24-100%) and 74% (35-124%) increase in hazard of MAKE, respectively. SCI was associated with MAKE and kidney failure after adjustment for occupational exposure, hypertension, diabetes, tobacco, alcohol use, history of AKI, baseline eGFR, uACR, and allowing baseline hazard to vary by centre. CONCLUSIONS: SCI is strongly and independently associated with composite MAKE in patients with mild to moderate CKD. Confirmation in other studies will allow consideration of SCI as a risk marker and treatment target.

6.
Inorg Chem ; 58(21): 14885-14899, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31609594

RESUMO

A multiple diglycolamide (DGA)-containing ligand having four DGA arms tethered to a tetraaza-12-crown-4 ring, viz. 2,2',2'',2'''-(((1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetrakis(2-oxoethane-2,1-diyl)) tetrakis (oxy)) tetrakis(N,N-dioctylacetamide) (T12C4ODGA), was synthesized and evaluated for the extraction of different actinide and lanthanide ions, viz. Am3+, Eu3+, Pu4+, Np4+, and UO22+. The extraction efficiency of the present ligand was found to be the highest reported so far, more specifically for the trivalent metal ions Am3+ and Eu3+, when one considers the very low ligand concentration used in the present study, compared to that of the various previously reported multiple DGA-based ligands. The nature of the complexes formed during the extraction of Eu3+ was investigated using time-resolved fluorescence (TRFS) and extended X-ray absorption fine structure (EXAFS) spectroscopy. Both the solvent extraction and TRFS studies indicated the presence of 1:1 and 1:2 complexes during the extraction of Am3+ and Eu3+ having three inner-sphere water molecules in the 1:1 complex. Density functional theoretical (DFT) studies were performed on the Am3+ and Eu3+ complexes of both T12C4ODGA and an analogous compound having methyl groups in place of the n-octyl groups, and the DFT results of the T12C4ODGA nicely explain the extraction behavior of Am3+ and Eu3+.

7.
Inorg Chem ; 57(20): 12987-12998, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30256631

RESUMO

A novel tripodal diglycolamide ligand containing a triazamacrocycle center (2,2',2''-(((1,4,7-triazonane-1,4,7-triyl)tris(2-oxoethane-2,1-diyl)) tris(oxy)) tris( N, N-dioctylacetamide), abbreviated as T9C3ODGA) was synthesized and characterized by conventional techniques. The ligand resulted in efficient extraction of actinide/lanthanide ions yielding the trend: Eu3+ > Pu4+ > Am3+ > NpO22+ > UO22+ > Sr2+ > Cs+. Similar to most of the other diglycolamide (DGA) ligands, Eu3+ was preferentially extracted as compared to Am3+; the separation factor ( DEu/ DAm) value at 3 M HNO3 was ca. 4.2. In contrast, separation from UO22+ ion was less effective as compared to that of other tripodal DGA ligands studied earlier. Solvent extraction studies indicated extraction of species of the ML2 (where L is T9C3ODGA) stoichiometry. The formation of an inclusion complex with no inner-sphere water molecule was confirmed from luminescence spectral studies. DFT computations predicted the presence of an inner-sphere nitrate ion in the most preferred complex, which was also supplemented by EXAFS and luminescence studies. The selectivity of T9C3ODGA could be explained on the basis of its more favorable interactions with Eu3+ as compared to those with Am3+ both in the gas and the solution phases.

8.
Nephrology (Carlton) ; 23(8): 791-796, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29633425

RESUMO

The literature on membranous nephropathy (MN) with monoclonal deposits on immunofluorescence (IF) and their outcome is very scarce. We report our experience of managing five patients with this clinical entity. The mean age of the patients was 33.2 ± 6.55 years. The mean proteinuria, serum albumin and serum creatinine was 5.73 ± 2.17 g/day, 2.86 ± 0.51 g/dL and 1.34 ± 1.19 mg/dL, respectively. None of the patients had a lymphoproliferative disorder. Only one patient had an elevated free light chain ratio. Four (80%) patients were M-type phospholipase A2 receptor (PLA2R) negative (tissue and serum), and one (20%) was PLA2R related. Three (60%) cases had monoclonal IgG3/k, one IgG3/λ, whereas one patient with PLA2R positivity had an IgG3/IgG4k subtype. Two (67%) patients treated with cyclical cyclophosphamide and steroids (cCYC/GC) achieved complete remission and one patient (33%) with elevated baseline creatinine had a reduction in serum creatinine with persistent proteinuria at the end of the 12th month of follow-up. One patient with PLA2R positive MN was treated with Rituximab and is in complete remission. The patient with an elevated free light chain at baseline was treated with Bortezomib/Thalidomide/Dexamethasone, had complete remission at 12 months, however, had a progressive rise in creatinine over the next 40 months of follow-up. The current series, though limited by numbers, documents the efficacy of conventional therapies in non-malignant associated MN with monoclonal deposits on IF.


Assuntos
Autoanticorpos/imunologia , Glomerulonefrite Membranosa/imunologia , Cadeias Leves de Imunoglobulina/imunologia , Rim/imunologia , Receptores da Fosfolipase A2/imunologia , Adulto , Biópsia , Feminino , Imunofluorescência , Glomerulonefrite Membranosa/diagnóstico , Glomerulonefrite Membranosa/tratamento farmacológico , Humanos , Imunossupressores/uso terapêutico , Rim/efeitos dos fármacos , Rim/ultraestrutura , Masculino , Microscopia Eletrônica , Indução de Remissão , Esteroides/uso terapêutico , Resultado do Tratamento , Adulto Jovem
9.
Indian J Med Res ; 144(1): 32-37, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27834323

RESUMO

BACKGROUND & OBJECTIVES: CNDP1 gene, present on chromosome 18q22.3-23, encodes carnosinase, the rate-limiting enzyme in hydrolysis of carnosine to ß-alanine and L-histidine. Linkage of CTG trinucleotide (leucine) repeat polymorphism in CNDP1 gene with diabetic nephropathy has been observed in several populations. However, this association is conflicting and population-dependent. We investigated this association in type 2 diabetes mellitus (T2DM) patients with and without nephropathy in north India. METHODS: A total of 564 individuals [199 T2DM without nephropathy (DM), 185 T2DM with nephropathy (DN) and 180 healthy individuals (HC)] were enrolled. CNDP1 CTG repeat analysis was done by direct sequencing of a 377 base pair fragment in exon 2. RESULTS: The most frequent leucine (L) repeats were 5L-5L, 6L-5L and 6L-6L. 5L-5L genotype frequency was reduced in DN (24.3%) as compared to DM (34.7%, P=0.035) and HC (38.4%, P=0.005). Similarly, 5L allele frequency was lower in DN (46.8%) as compared to DM (57.3%, P=0.004) and HC (60.5%, P<0.001). The genotype and allelic frequencies were similar in DM and HC groups. No gender specific difference was observed in the genotype or allelic frequencies between groups. INTERPRETATION & CONCLUSIONS: Compared to healthy individuals and those with diabetes but no kidney disease, patients with diabetic nephropathy exhibited lower frequencies of 5L-5L genotype and 5L allele of CNDP1 gene, suggesting that this allele might confer protection against development of kidney disease in this population.


Assuntos
Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/genética , Dipeptidases/genética , Estudos de Associação Genética , Adolescente , Adulto , Idoso , Alelos , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Repetições de Trinucleotídeos/genética
10.
Nephrology (Carlton) ; 21(6): 483-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26428957

RESUMO

AIM: Blood levels of 25-hydroxyvitamin D [25(OH) D] are reduced in patients with nephrotic syndrome (NS). The lowering is thought to be due to urinary loss of vitamin D binding protein (DBP). A link between vitamin D deficiency and bone disease or markers of mineral metabolism has not yet been shown in NS. We hypothesized that alterations in bioavailable vitamin D levels might be linked to these abnormalities in NS. METHODS: We measured circulating levels of 25(OH)D, 1,25-dihydroxyvitamin D [1,25(OH)2 D], DBP, serum albumin and intact parathyroid hormone (iPTH) in 106 adults with sporadic idiopathic NS and 40 healthy controls. Bioavailable vitamin D was calculated from previously validated formulae. Bone mineral density (BMD) was measured at left hip (neck of femur) by DEXA. RESULTS: Compared to healthy controls, total and bioavailable 25(OH)D levels were significantly reduced in patients with NS as compared to healthy controls. Among the nephrotic patients, BMD was positively correlated with bioavailable 25(OH)D (r = 0.358; P = 0.0002) but not with total 25(OH)D (r = 0.174; P = 0.079). Total 1,25(OH)2 D and bioavailable 1,25(OH)2 D did not correlate with BMD (r = 0.131; P = 0.206 and r = 0.107, P = 0.295). Bioavailable 25(OH)D levels showed a strong inverse correlation with iPTH on univariate (r = -0.457; P < 0.0001) and multivariate (ß=-0.453, P < 0.0001) analyses. CONCLUSIONS: We conclude that bioavailable 25(OH)D is a better measure of vitamin D status with respect of BMD and mineral metabolism in patients of nephrotic syndrome.


Assuntos
Densidade Óssea , Remodelação Óssea , Colo do Fêmur/metabolismo , Síndrome Nefrótica/sangue , Deficiência de Vitamina D/sangue , Vitamina D/análogos & derivados , Absorciometria de Fóton , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Transversais , Regulação para Baixo , Feminino , Colo do Fêmur/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/fisiopatologia , Hormônio Paratireóideo/sangue , Valor Preditivo dos Testes , Albumina Sérica/análise , Albumina Sérica Humana , Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico , Deficiência de Vitamina D/fisiopatologia , Proteína de Ligação a Vitamina D/sangue , Adulto Jovem
11.
Ren Fail ; 38(6): 894-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27266801

RESUMO

Collapsing focal segmental glomerulosclerosis (cFSGS) is characterized by rapid progression to end-stage renal disease (ESRD). We evaluated the clinicopathological spectrum of cFSGS and compared its clinical behavior to steroid and tacrolimus (TAC)-resistant noncollapsing focal segmental glomerulosclerosis (FSGS). All patients (>14 years) diagnosed with cFSGS were enrolled in the study. Staining for differentiated podocyte markers such as WT 1, PAX and KI67 were performed in all patients. The outcome and histological features of cFSGS was compared with a prospectively followed cohort of steroid and TAC-resistant noncollapsing FSGS. The study included 22 cFSGS patients and 19 cases of steroid and TAC-resistant FSGS. Complete remission, partial remission, steroid resistance, progression to ESRD and death were observed in 13.6%, 4.5%, 27.3%, 36.4% and 18.2% patients, respectively. Patients with cFSGS had higher serum creatinine and more advanced tubulointerstitial changes compared to resistant FSGS. Twenty-six percent of therapy resistant noncollapsing FSGS progressed to ESRD after two years of stopping TAC. However, there was no difference in progression to ESRD between cFSGS and therapy-resistant noncollapsing FSGS at the end of two years. Glomerular collapse in the setting of FSGS is poorly responsive to treatment and has a high rate of progression to ESRD. The long-term prognosis of cFSGS and steroid and TAC-resistant FSGS are similar.


Assuntos
Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Glomerulosclerose Segmentar e Focal/patologia , Imunossupressores/uso terapêutico , Falência Renal Crônica/epidemiologia , Esteroides/uso terapêutico , Tacrolimo/uso terapêutico , Adolescente , Adulto , Creatinina/sangue , Progressão da Doença , Feminino , Glomerulosclerose Segmentar e Focal/complicações , Humanos , Glomérulos Renais/patologia , Masculino , Pessoa de Meia-Idade , Podócitos/patologia , Prognóstico , Estudos Prospectivos , Indução de Remissão , Adulto Jovem
12.
Nephrology (Carlton) ; 20(1): 25-33, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25230334

RESUMO

AIM: This pilot study assesses the safety and feasibility of autologous mesenchymal stromal cell (MSC) transplantation in four patients that underwent living donor renal transplantation, and the effect on the immunophenotype and functionality of peripheral T lymphocytes following transplantation. METHODS: All patients received low dose ATG induction followed by calcineurin inhibitor-based triple drug maintenance immunosuppression. Autologous MSCs were administered intravenously pre transplant and day 30 post-transplant. Patients were followed up for 6 months. The frequency of regulatory T cells and T cell proliferation was assessed at different time points. RESULTS: None of the four patients developed any immediate or delayed adverse effects following MSC infusion. All had excellent graft function, and none developed graft dysfunction. Protocol biopsies at 1 and 3 months did not reveal any abnormality. Compared to baseline, there was an increase in the CD4 + CD25+FOXP3+ regulatory T cells and reduction in CD4 T cell proliferation. CONCLUSION: We conclude that autologous MSCs can be used safely in patients undergoing living donor renal transplantation, lead to expansion of regulatory T cells and decrease in T cell proliferation. Larger randomized trials studies are needed to confirm these findings and evaluate whether this will have any impact on immunosuppressive therapy.


Assuntos
Transplante de Rim , Transplante de Células-Tronco Mesenquimais , Adulto , Feminino , Humanos , Doadores Vivos , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Projetos Piloto , Linfócitos T , Transplante Autólogo , Resultado do Tratamento
13.
ACS Omega ; 9(25): 27289-27299, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38947836

RESUMO

Hydroxycarboxylic acids, viz., α-hydroxyisobutyric acid (HIBA) and mandelic acid (MA), have been widely employed as eluents for inner transition metal separation studies. Both extractants have identical functional groups (OH and COOH) with different side-chains. Despite their similarities in binding motifs, they show different retention behaviors for thorium and uranium in liquid chromatography. To understand the mechanism behind the trend, a detailed study on the aqueous phase interaction of thorium with both extractants is carried out by speciation, spectroscopy, and density functional theory-based calculations. Potentiometric titration experiments are carried out to reveal the stability and species formed. Electrospray ionization mass spectrometry is performed to identify the formation of different species by Th with both HIBA and MA. It is seen that for Th-HIBA and Th-MA, the dominating species are ML3 and ML4, respectively. A similar pattern observed in potentiometric speciation analysis supports the tendency of Th to form higher stoichiometric species with MA than with HIBA. The difference in the dominating species thus helps in explaining the reversal in the retention behavior of uranium and thorium in the reverse-phase liquid chromatographic separation. The results obtained are corroborated with extended X-ray absorption fine structure spectroscopic measurements and density functional theory (DFT) calculations.

14.
ACS Synth Biol ; 13(7): 1994-2007, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38899943

RESUMO

The advancement in nanotechnology has completely revolutionized various fields, including pharmaceutical sciences, and streamlined the potential therapeutic of many diseases that endanger human life. The synthesis of green nanoparticles by biological processes is an aspect of the newly emerging scientific field known as "green nanotechnology". Due to their safe, eco-friendly, nontoxic nature, green synthesis tools are better suited to produce nanoparticles between 1 and 100 nm. Nanoformulation of different types of nanoparticles has been made possible by using green production techniques and commercially feasible novel precursors, such as seed extracts, algae, and fungi, that act as potent reducing, capping, and stabilizing agents. In addition to this, the biofunctionalization of nanoparticles has also broadened its horizon in the field of environmental remediation and various novel therapeutic innovations including wound healing, antimicrobial, anticancer, and nano biosensing. However, the major challenge pertaining to green nanotechnology is the agglomeration of nanoparticles that may alter the surface topology, which can affect biological physiology, thereby contributing to system toxicity. Therefore, a thorough grasp of nanoparticle toxicity and biocompatibility is required to harness the applications of nanotechnology in therapeutics.


Assuntos
Recuperação e Remediação Ambiental , Química Verde , Nanopartículas , Nanopartículas/química , Química Verde/métodos , Recuperação e Remediação Ambiental/métodos , Humanos , Nanotecnologia/métodos
17.
BMC Nephrol ; 14: 262, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24289828

RESUMO

BACKGROUND: The current treatment options for idiopathic membranous nephropathy (IMN) carry significant toxicity. In this prospective, observational pilot study, we used single time infusion of bone marrow derived autologous mononuclear cells (MNCs) in adult patients with treatment refractory IMN. METHODS: Twelve patients of biopsy proven IMN who had failed a cyclical 6-month regimen of steroid and cyclophosphamide were enrolled in the study. Bone-marrow was harvested from the iliac crest and underwent processing to isolate MNCs. Cells were counted and subjected to viability testing before being infused through a peripheral vein on the same day. After the infusion, subjects were followed up monthly for the next six months. Supportive treatment including angiotensin antagonists and statins was continued throughout the study period. RESULT: The proteinuria, serum albumin and creatinine values at entry were 2.97 ± 0.6 gm/1.73 m2/d, 2.27 ± 1.1 gm/l and 0.9 ± 0.8 mg/dl respectively. There was a reduction in proteinuria (p < 0.0001), and increase in serum albumin (p = 0.001) at 1 month, with 64% of the subjects showing >50% reduction in proteinuria. However, the response was ill sustained. At 6 months, only 2 patients had >50% reduction. Serum creatinine remained stable throughout the study period. No infusion related side effects were noted. CONCLUSION: Autologous mononuclear cell infusion leads to transitory reduction in proteinuria and improvement in serum albumin in treatment refractory IMN. This effect, however, is transient. Whether this can be overcome by repeated infusion of cultured mesenchymal cells needs to be investigated.


Assuntos
Transplante de Medula Óssea/métodos , Glomerulonefrite Membranosa/complicações , Transplante de Células-Tronco Mesenquimais/métodos , Proteinúria/etiologia , Proteinúria/prevenção & controle , Adolescente , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Resultado do Tratamento , Adulto Jovem
18.
Mediators Inflamm ; 2013: 384807, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24347824

RESUMO

BACKGROUND: CD4(+)CD28(null) T cells are expanded in peripheral blood of patients with chronic kidney disease and associated with subclinical atherosclerosis. However, triggers for the oligoclonal expansion and activation of these cells are not clear. METHODS: We investigated twenty-five stage V-IV chronic kidney disease (CKD) patients and eight healthy subjects (HC). Peripheral mononuclear cells were isolated and incubated with heat shock protein- (HSP) 60 and 70. CD4(+)CD28(null) and CD4(+)CD28(+) cells were sorted by flowcytometry and antigen specific response was assessed by the mRNA and protein expression of interferon (IFN)-γ, perforin, and granzyme B using qRT-PCR and Elispot. RESULTS: The basal mRNA expression of IFN-γ, perforin, and granzyme B in CD4(+)CD28(null) cells was higher in subjects with CKD compared to that in HC (P < 0.0001). Subjects with CKD also showed expression of IFN-γ, perforin, and granzyme B in the CD4(+)CD28(+) subset, but this was much weaker than that seen in the CD4(+)CD28(null) population (P < 0.0001). We did not note the expression of these molecules at mRNA or protein level in either subset of CD4 cells in HC. After incubation with HSP60 and HSP70, CD4(+)CD28(null) cells showed increased expression at mRNA (P < 0.001) and protein level (P < 0.001). CD4(+)CD28(+) cells also showed a weak increase in expression. No antigen-specific response was noted in HC. CONCLUSION: These data show that CD4(+)CD28(null) cells in subjects with CKD react with HSP60 and HSP70 by upregulating the expression of IFN-γ, perforin and granzyme B. Increased circulating level of HSP60 and HSP70 might play a role in initiation and/or progression of atherosclerosis in CKD subjects through perturbation of CD4(+)CD28(null) cells.


Assuntos
Antígenos CD28/fisiologia , Linfócitos T CD4-Positivos/imunologia , Chaperonina 60/fisiologia , Proteínas de Choque Térmico HSP70/fisiologia , Proteínas Mitocondriais/fisiologia , Insuficiência Renal Crônica/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Aterosclerose/etiologia , Citotoxicidade Imunológica , Feminino , Granzimas/análise , Granzimas/genética , Humanos , Interferon gama/análise , Interferon gama/genética , Masculino , Pessoa de Meia-Idade , Perforina/análise , Perforina/genética , Insuficiência Renal Crônica/complicações
19.
Indian J Nephrol ; 33(6): 444-448, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38174303

RESUMO

Introduction: Vitamin D deficiency and anemia frequently coexist. Moreover, vitamin D deficiency is found to play a role in chronic kidney disease (CKD)-associated anemia. We investigated the effect of cholecalciferol on serum hepcidin levels in vitamin D-deficient, non-diabetic individuals with CKD in a randomized, double-blind, placebo-controlled trial. Methods: This study was performed on stored samples of our previously published randomized, double-blind, placebo-controlled trial of cholecalciferol supplementation in non-diabetic patients with stage III-IV CKD and vitamin D deficiency. Stable patients of either sex, aged 18-70 years, with non-diabetic stage III-IV CKD (estimated glomerular filtration rate between 15 and 60 ml/min/1.73 m2), and having serum 25-hydroxyvitamin D3 [25(OH) D] levels ≤20 ng/ml were included. Participants received either two directly observed oral doses of cholecalciferol (300,000 IU) or matching placebo at baseline and at eight weeks. Follow-up was done at 16 weeks. Serum hepcidin levels were analyzed at baseline and at 16 weeks. Results: A total of 120 CKD patients were enrolled. Serum 25(OH) D levels were similar in the placebo and cholecalciferol groups at baseline (13.21 ± 4.78 ng/ml and 13.40 ± 4.42 ng/ml; P = 0.88). After 16 weeks, the serum 25(OH) D levels were found to be increased in the cholecalciferol group but not in the placebo group (between-group difference in mean change 23.40 ng/ml; 95% CI: 19.76 to 27.06; P < 0.001). Serum hepcidin levels were similar at baseline (median [IQR]: 33.6 [8.6-77.8] ng/ml vs. 24.6 [9.3-70.7] ng/ml, P = 0.903) and did not vary between groups at 16 weeks (median [IQR]: 41.5 [10.9-75.0] ng/ml vs. 34.8 [12.3-63.75] ng/ml, P = 0.703). Conclusion: Our study provides preliminary data based on which a larger adequately powered clinical trial can be conducted to conclusively assess the impact of vitamin D supplementation on hepcidin levels and anemia in patients with CKD and vitamin D deficiency.

20.
Indian J Nephrol ; 33(4): 277-282, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781560

RESUMO

Background and Aim: Primary glomerular disease accounts for one-sixth of all chronic kidney diseases (CKDs) in India. We remain limited in our ability to effectively treat these conditions because of lack of understanding of the disease mechanisms and lack of predictors to identify the clinical course and therapeutic responsiveness. We propose to develop a network of investigators in glomerular diseases, collect information in a systematic fashion to understand the clinical outcomes, answer translational research questions better, and identify and recruit patients for clinical trials. Materials and Methods: This is a prospective, observational study. The Indian TrANslational GlomerulonephrItis BioLogy nEtwork (I-TANGIBLE) cohort will enroll patients (>18 years) with biopsy-proven minimal change disease (MCD), focal segmental glomerulonephritis (FSGS), membranous nephropathy (MN), IgA nephropathy (IgAN), or membranoproliferative glomerulonephritis (MPGN) (immune complex- and complement-mediated), with first biopsy taken within 2 years of enrollment. Patients with estimated glomerular filtration (eGFR) rate <15 ml/min/1.73 m2 for >3 months at the time of screening, kidney transplant or bone marrow transplant recipients, patients with active malignancy, and patients with active hepatitis B/C replication or human immunodeficiency virus (HIV)-I/II will be excluded. Clinical details including history, medication history and details, and family history will be obtained. Consenting patient's blood and urine samples will be collected and stored, aligned to their clinical follow-up. Expected Outcomes: The network will allow accurate ascertainment of disease burden of glomerular diseases across study sites, establishment of the treatment pattern of common glomerular diseases, investigation of medium- and long-term outcomes (remission, relapse, rate of eGFR decline), and building a suitable infrastructure to carry out clinical trials in primary glomerular disease.

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