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1.
Plant Cell Environ ; 46(11): 3501-3517, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37427826

RESUMO

Plants deposit lignin in the secondary cell wall as a common response to drought and pathogen attacks. Cell wall localised multicopper oxidase family enzymes LACCASES (LACs) catalyse the formation of monolignol radicals and facilitate lignin formation. We show an upregulation of the expression of several LAC genes and a downregulation of microRNA397 (CamiR397) in response to natural drought in chickpea roots. CamiR397 was found to target LAC4 and LAC17L out of twenty annotated LACs in chickpea. CamiR397 and its target genes are expressed in the root. Overexpression of CamiR397 reduced expression of LAC4 and LAC17L and lignin deposition in chickpea root xylem causing reduction in xylem wall thickness. Downregulation of CamiR397 activity by expressing a short tandem target mimic (STTM397) construct increased root lignin deposition in chickpea. CamiR397-overexpressing and STTM397 chickpea lines showed sensitivity and tolerance, respectively, towards natural drought. Infection with a fungal pathogen Macrophomina phaseolina, responsible for dry root rot (DRR) disease in chickpea, induced local lignin deposition and LAC gene expression. CamiR397-overexpressing and STTM397 chickpea lines showed more sensitivity and tolerance, respectively, to DRR. Our results demonstrated the regulatory role of CamiR397 in root lignification during drought and DRR in an agriculturally important crop chickpea.

2.
J Exp Bot ; 74(1): 130-148, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36205079

RESUMO

Flower and seed coat colour are important agronomic traits in chickpea (Cicer arietinum L.). Cultivated chickpeas are of two types namely, desi (dark seeded, purple flowered) and kabuli (light seeded, white flowered). There has been limited information about the molecular mechanism underlying colour variation of flower and seed coats in desi and kabuli chickpea. We profiled the anthocyanin and proanthocyanidin (PA) contents in chickpea flowers and seed coats. Tissue-specific silencing of two genes encoding a basic helix-loop-helix (CabHLH) protein and a tonoplast-localized multidrug and toxic compound extrusion (CaMATE1) transporter in a desi genotype resulted in the reduction in expression of anthocyanin and PA biosynthetic genes and anthocyanin and PA contents in the flower and seed coat, and produced flowers and seeds with kabuli characteristics. Transcriptional regulation of a subset of anthocyanin and PA biosynthetic genes by a natural CabHLH variant and transport assay of a natural CaMATE1 variant explained the association of these alleles with the kabuli phenotype. We carried out a detailed molecular characterization of these genes, and provided evidence that kabuli chickpea flower and seed colour phenotypes can be derived by manipulation of single genes in a desi chickpea background.


Assuntos
Cicer , Proantocianidinas , Cicer/genética , Antocianinas/metabolismo , Proantocianidinas/metabolismo , Cor , Sementes/genética , Sementes/metabolismo , Flores/genética
3.
J Zoo Wildl Med ; 52(4): 1286-1297, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34998302

RESUMO

Elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV HD) is an acute viral infection of growing Asian elephants (Elephas maximus). Four apparently healthy subadult Asian elephants aged between 6 and 10 yr at Nandankanan Zoological Park (NKZP), India, died of EEHV HD during August-September 2019. All four elephants were rescued from different reserved forests of Odisha state at less than 1 yr of age and hand reared in the NKZP. Elephants exhibited the clinical signs of lethargy, head swelling, fever, loss of appetite, abdominal distension, scant urination and defecation, signs of colic, lameness, trunk discharge, cyanosis/ulceration of tongue, erratic behavior, and recumbence before death. Period of illness varied between 28 and 42 h. Thrombocytopenia was the common significant hematological observation. No significant biochemical alterations were recorded except for higher creatinine concentrations. Analysis of blood samples in RT-PCR assay using two different sets of primers and probes that targeted terminase gene and major DNA-binding protein gene followed by cPCR and sequencing was positive for EEHV-1A in all four animals. Postmortem examination of all four carcasses showed hemorrhages in internal organs, including the hard palate, heart, lungs, stomach, mesenteric lymph nodes, mesentery, colon serosa, spleen, liver, kidney, and meninges. Histopathology showed congestion and/or hemorrhages in heart, lung, brain, kidney, and liver. There was presence of intranuclear inclusion bodies in the sinusoidal epithelial cells. The outbreak of EEHV HD that resulted in the acute death of four juvenile captive Asian elephants within <30 d, the first of its kind documented in India, is increasing the fear of similar outbreaks in the future.


Assuntos
Infecções por Herpesviridae , Herpesviridae , Animais , Animais de Zoológico , Surtos de Doenças/veterinária , Hemorragia/veterinária , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/veterinária , Índia
4.
Plant Biotechnol J ; 18(11): 2225-2240, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32181964

RESUMO

Cytokinin group of phytohormones regulate root elongation and branching during post-embryonic development. Cytokinin-degrading enzymes cytokinin oxidases/dehydrogenases (CKXs) have been deployed to investigate biological activities of cytokinin and to engineer root growth. We expressed chickpea cytokinin oxidase 6 (CaCKX6) under the control of a chickpea root-specific promoter of CaWRKY31 in Arabidopsis thaliana and chickpea having determinate and indeterminate growth patterns, respectively, to study the effect of cytokinin depletion on root growth and drought tolerance. Root-specific expression of CaCKX6 led to a significant increase in lateral root number and root biomass in Arabidopsis and chickpea without any penalty to vegetative and reproductive growth of shoot. Transgenic chickpea lines showed increased CKX activity in root. Soil-grown advanced chickpea transgenic lines exhibited higher root-to-shoot biomass ratio and enhanced long-term drought tolerance. These chickpea lines were not compromised in root nodulation and nitrogen fixation. The seed yield in some lines was up to 25% higher with no penalty in protein content. Transgenic chickpea seeds possessed higher levels of zinc, iron, potassium and copper. Our results demonstrated the potential of cytokinin level manipulation in increasing lateral root number and root biomass for agronomic trait improvement in an edible legume crop with indeterminate growth habit.


Assuntos
Cicer , Cicer/genética , Secas , Oxirredutases , Raízes de Plantas
5.
Chemistry ; 24(60): 16149-16159, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30095191

RESUMO

Lanthanide doping through a crystal site engineering approach tunes the emission wavelength suitable for LED applications, but weak emission from low coordination sites remains a huge challenge. Herein the use of a sensitizer is reported to enhance the emission strength and unravel the crystallinity and phase, as this approach demands a large amount of dopants. Doping of Eu2+ ions at SrO10 and SrO9 sites of Sr2 SiO4 (S2 S), respectively, tunes the emission from green to yellow and controlled doping of a Ce3+ sensitizer quadruples the quantum efficiency of yellow emission. Remarkably, doping of Eu2+ at the SrO9 site produces polycrystals, whereas co-doping of Ce3+ and Eu2+ at the same site produces single crystals. DFT calculations further delineate the underlying changes wherein strong interaction of dopant with its neighbours determines the electron density, and thus the crystallinity and phase, rather than usual explanation of aliovalent conditions, which is further substantiated by TEM results. Irrespective of dopant valence, use of large amounts of dopants and their interaction with the host is responsible for the crystallinity and phase change (α'-S2 S to ß-S2 S). The XPS valence band spectra experimentally evidences the changes in bonding nature of O 2p and O 2s orbitals of silicate and its electron density, due to doping at the two sites. In short, the outcomes resulting from this work could be extended for the development of other two-coordination site lanthanide-doped materials and crystallization of inorganic materials.

6.
Inorg Chem ; 57(3): 935-950, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29356513

RESUMO

The europium ion probes the symmetry disorder in the crystal structure, although the distortion due to charge compensation in the case of aliovalent dopant remains interesting, especially preparation involves low and high temperatures. This work studies the preparation of the ß-Ca2SiO4 (from here on C2S) particle from Pechini (C2SP) and hydrothermal (C2SH) methods, and its luminescence variance upon doping with Eu2+ and Eu3+ ions. The blue shift of the charge-transfer band (CTB) in the excitation spectra indicates a larger Eu3+-O2- distance in Eu3+ doped C2SH. The changes in vibrational frequencies due to stretching and bending vibrations in the FTIR and the Raman spectra and binding energy shift in the XPS analysis confirmed the distorted SiO44- tetrahedra in C2SH. The high hydrothermal temperature and pressure produce distortion, which leads to symmetry lowering although doping of aliovalent ion may slightly change the position of the Ca atoms. The increasing asymmetry ratio value from C2SP to C2SH clearly indicates that the europium ion stabilized in a more distorted geometry. It is also supported by Judd-Ofelt analysis. The concentration quenching and site-occupancy of Eu3+ ions in two nonequivalent sites of C2S were discussed. The charge state and concentration of europium ions in C2SP and C2SH were determined using X-ray photoelectron spectroscopy measurements. The C2S particles were studied by X-ray powder diffraction, FTIR, Raman, BET surface area, TGA/DTA, electron microscopy, XPS, and luminescence spectroscopy. The impact of citrate ion on the morphology and particle size of C2SH has been hypothesized on the basis of the microscopy images. This study provides insights that are needed for further understanding the structure of C2S and thereby improves the applications in optical and biomedical areas and cement hydration.

7.
Inorg Chem ; 57(2): 821-832, 2018 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-29292994

RESUMO

Studies have been carried out to understand the specific role of the alkali charge compensator on the luminescence properties of an alkali ion (Li+, Na+, and K+) codoped SrWO4:Eu phosphor. The oxidation state of the europium ion was found to be +3 on the basis of X-ray absorption near edge structure (XANES) measurements. This is the first report of its kind where opposite effects of Li+ ion and Na+/K+ ions on photoluminescence intensity have been observed. Li+ ion codoping enhanced the photoluminescence intensity from SrWO4:Eu3+ phosphor while Na+/K+ ion codoping did not. On the other hand, the luminescence lifetime is maximum for the Na+ ion codoped sample and minimum for the Li+ ion codoped sample. The results could be explained successfully using time-resolved luminescence, positron annihilation lifetime spectroscopy (PALS), and extended X-ray absorption fine structure (EXAFS) spectroscopy measurements. Changes in the Eu-O bond length and Debye-Waller Factor (σ2) upon Li+/Na+/K+ codoping were monitored through EXAFS measurements. PALS also highlighted the fact that Li+ codoping is not contributing to reduction in the cation vacancies and might be occupying interstitial sites rather than lattice positions due to its very small size. On europium doping there is lowering in symmetry of SrO8 polyhedra from S4 to C6, which is reflected in an intense electric dipole transition in comparison to the magnetic dipole transition. This is also corroborated using trends in Judd-Ofelt parameters. The results have shown that the luminescence lifetime is better when the vacancy concentration is lower as induced by Na+ and K+ codoping, while the emission intensity is higher in the samples when distortion around Eu3+ is reduced as induced by Li+ codoping.

8.
Inorg Chem ; 56(1): 167-178, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-27966936

RESUMO

Considering the fact that pyrophosphate-based hosts are in high demand for making highly efficient luminescence materials, we doped two visible lanthanide ions, viz. Sm3+ and Eu3+, in Zn2P2O7. Interestingly, it was oberved that pure Zn2P2O7 displayed blue-green dual emission on irradiation with ultraviolet light. Emission and lifetime spectroscopy shows the presence of defects in pyrophosphate samples which are responsible for such emission. DFT calculations clearly pinpointed that the electronic transitions between defect states located at just below the conduction band minimum (arises due to VO1+ and VO2+ defects) and valence band maximum, as well as impurity states situated in the band gap, can lead to dual emission in the blue-green region, as is also indicated by emission and lifetime spectra. X-ray absorption near edge spectroscopy (XANES) shows the stabilization of europium as well as samarium ion in the +3 oxidation state in α-Zn2P2O7. The fact that α-Zn2P2O7 has two different coordination numbers for zinc ions, i.e. five- and six-coordinate, the study of dopant ion distribution in this particular matrix will be an important step in realizing a highly efficient europium- and samarium-based red-emitting phosphor. Time resolved photoluminescence (TRPL) shows that both of these ions are heterogeneously distributed between five- and six-coordinated Zn2+ sites and it is the six-coordinated Zn2+ site which is the most favorable for lanthanide ion doping. Extended X-ray absorption fine structure (EXAFS) measurements also suggested that a six-coordinated zinc ion is the preferred site occupied by trivalent lanthanide ions, which is in complete agreement with TRPL results. It was observed that there is almost complete transfer of photon energy from Zn2P2O7 to Eu3+, whereas this transfer is inefficient and almost incomplete in case of Sm3+, which is indeed important information for the realization of pyrophosphate-based tunable phosphors.

9.
Phys Chem Chem Phys ; 19(19): 11975-11989, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28443926

RESUMO

MgO particles of few micron size are synthesized through a sol-gel method at different annealing temperatures such as 600 °C (MgO-600), 800 °C (MgO-800) and 1000 °C (MgO-1000). EDX and ICP-AES studies confirmed a near total purity of the sample with respect to paramagnetic metal ion impurities. Magnetic measurements showed a low temperature weak ferromagnetic ordering with a TC (Curie temperature) around 65 K (±5 K). Unexpectedly, the saturation magnetization (Ms) was found to be increased with increasing annealing temperature during synthesis. It was observed that with J = 1 or 3/2 or S = 1 or 3/2, the experimental points are fitted well with the Brillouin function of weak ferromagnetic ordering. A positron annihilation lifetime measurement study indicated the presence of a divacancy (2VMg + 2VO) cluster in the case of the low temperature annealed compound, which underwent dissociations into isolated monovacancies of Mg and O at higher annealing temperatures. An EPR study showed that both singly charged Mg vacancies and oxygen vacancies are responsible for ferromagnetic ordering. It also showed that at lower annealing temperatures the contribution from was very low while at higher annealing temperatures, it increased significantly. A PL study showed that most of the F+ centers were present in their dimer form, i.e. as centers. DFT calculation implied that this dimer form has a higher magnetic moment than the monomer. After a careful consideration of all these observations, which have been reported for the first time, this thermally tunable unusual magnetism phenomenon was attributed to a transformation mechanism of one kind of cluster vacancy to another.

10.
Inorg Chem ; 55(4): 1728-40, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26824394

RESUMO

SrZrO3 perovskite (SZP) was synthesized using gel-combustion route and characterized systematically using X-ray diffraction and time-resolved photoluminescence techniques. A detailed analysis of the optical properties of Tb(3+) ions in SrZrO3 was performed to correlate them with the local environment of the lanthanide ions in this perovskite. Photoluminescence (PL) spectroscopy showed that emission spectrum consists of host as well as Tb(3+) emission indicating the absence of complete host-dopant energy transfer. On the basis of emission spectrum and PL decay study it was also observed that Tb(3+) is not homogeneously distributed in SrZrO3 perovskite; rather, it is occupying two different sites. It is corroborated using extended X-ray absorption fine structure studies that Tb(3+) is stabilized on both six-coordinated Zr(4+) and eight-coordinated Sr(2) site. The energies calculated using density functional theory (DFT) indicates that Tb occupation in Sr site is energetically more favorable than Zr site. The analysis of valence charge distribution also substantiated our structural stability analysis of site-selective Tb doping in SrZrO3. Time-resolved emission spectroscopy is employed to elucidate the difference in the spectral feature of Tb(3+) ion at Sr(2+) and Zr(4+) site. DFT-calculated density of states analysis showed that energy mismatch of Tb-d states with Zr-d and O-p states of SZP makes the energy transfer from host SZP to Tb(3+) ion difficult.

11.
Am J Orthod Dentofacial Orthop ; 150(6): 1020-1027, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27894523

RESUMO

INTRODUCTION: Biochemical markers are agents directly involved in bone growth and remodeling and can be quantitatively evaluated from various biologic fluids. The aim of this study was to assess the changes in the levels of insulin-like growth factor-1 (IGF-1) in serum and urine as a growth maturity indicator and to compare them with the cervical vertebral maturation radiographic stages. METHODS: The study was conducted with 72 female subjects aged 8 to 20 years. Cervical vertebral maturation stages, and serum and urine IGF-1 levels were recorded for all subjects, and the subjects were equally divided into the 6 cervical vertebral maturation groups. Median values of IGF-1 for each stage of cervical vertebral maturation were calculated and statistically compared with those of the other stages. RESULTS: The levels of serum and urine IGF-1 at stage 4 of cervical vertebral maturation were significantly higher than those from the other stages (P <0.01). Stage 4 corresponded to a mean age of 13.67 years. A significant correlation was observed between serum and urine IGF-1 (P <0.001). CONCLUSIONS: Urine IGF-1 follows the growth curve similar to serum IGF-1. Thus, urine IGF-1 may be regarded as a promising noninvasive tool for growth assessment. Further research is necessary to validate these results in a different population and with a larger sample.


Assuntos
Desenvolvimento Ósseo , Fator de Crescimento Insulin-Like I/análise , Adolescente , Biomarcadores/sangue , Biomarcadores/urina , Desenvolvimento Ósseo/fisiologia , Osso e Ossos/anatomia & histologia , Vértebras Cervicais/anatomia & histologia , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/crescimento & desenvolvimento , Criança , Estudos Transversais , Feminino , Humanos , Fator de Crescimento Insulin-Like I/urina , Puberdade/sangue , Puberdade/urina , Radiografia , Adulto Jovem
12.
Curr Genet ; 60(4): 327-41, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25070039

RESUMO

Rhizoctonia solani is an important necrotrophic fungal pathogen which causes disease on diverse plant species. It has been classified into 14 genetically distinct anastomosis groups (AGs), however, very little is known about their genomic diversity. AG1-IA causes sheath blight disease in rice and controlling this disease remains a challenge for sustainable rice cultivation. Recently the draft genome sequences of AG1-IA (rice isolate) and AG1-IB (lettuce isolate) had become publicly available. In this study, using comparative genomics, we report identification of 3,942 R. solani genes that are uniquely present in AG1-IA. Many of these genes encode important biological, molecular functions and exhibit dynamic expression during in-planta growth of the pathogen in rice. Based upon sequence similarity with genes that are required for plant and human/zoonotic diseases, we identified several putative virulence/pathogenicity determinants amongst AG1-IA specific genes. While studying the expression of 19 randomly selected genes, we identified three genes highly up-regulated during in-planta growth. The detailed in silico characterization of these genes and extent of their up-regulation in different rice genotypes, having variable degree of disease susceptibility, suggests their importance in rice-Rhizoctonia interactions. In summary, the present study reports identification, functional characterization of AG1-IA specific genes and predicts important virulence determinants that might enable the pathogen to grow inside hostile plant environment. Further characterization of these genes would shed useful insights about the pathogenicity mechanism of AG1-IA on rice.


Assuntos
Proteínas Fúngicas/genética , Genoma Fúngico/genética , Lactuca/microbiologia , Oryza/microbiologia , Doenças das Plantas/microbiologia , Rhizoctonia/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Genótipo , Modelos Biológicos , Anotação de Sequência Molecular , Folhas de Planta/microbiologia , Brotos de Planta/microbiologia , Rhizoctonia/metabolismo , Rhizoctonia/patogenicidade , Análise de Sequência de DNA , Especificidade da Espécie , Regulação para Cima , Virulência
13.
Indian J Med Res ; 139(4): 544-54, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24927340

RESUMO

BACKGROUND & OBJECTIVES: The prerequisite of radioimmunotherapy is stable binding of a radionuclide to monoclonal antibodies, which are specific to the tumour-associated antigen. Most B-cell lymphomas express CD20 antigen on the surface of the tumour cells, making it a suitable target for therapeutic radioactive monoclonal antibodies. In the present study, the immunoconjugate of biosimilar Rituximab (Reditux™) and macrocyclic chelator, p-SCN-Bz-DOTA, was prepared and radiolabelled with Lutetium-177 followed by quality control procedures. METHODS: Rituximab(BioSim) was desalted with sodium bicarbonate (0.1M, pH 9.0) and incubated with DOTA-SCN (1:50). The effectiveness of the conjugation was evaluated by determining the number of chelators per antibody molecule. This conjugate was radiolabelled with Lutetium-177 and purified using PD10 column. The quality control parameters like pH, clarity, radiochemical purity, in vitro stability and sterility were studied. Immunoreactivity of 177 Lu-DOTA-Rituximab (BioSim) was assessed using RAMOS cells. The radioimmunoconjugate (RIC) after stringent quality assurance was injected in three patients and the biodistribution profile was analysed. RESULTS: An average of 4.25 ± 1.04 p-SCN-Bz-DOTA molecules could be randomly conjugated to a single molecule of Rituximab (BioSim).The radiochemical purity of the labelled antibody was > 95 per cent with preserved affinity for CD20 antigen. The final preparation was stable up to about 120 h when tested under different conditions. A favourable biodistribution profile was observed with liver showing the maximum uptake of the RIC. INTERPRETATION & CONCLUSIONS: A favourable radiochemical purity, stability and biodistribution of the radiolabelled immunoconjugate indicate that clinical trials for evaluation of toxicity and efficacy of 177 Lu-DOTA-antiCD20 antibody-Rituximab (BioSim) in patients of relapsed and refractory non Hodgkin's lymphoma can be considered.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Imunoconjugados/uso terapêutico , Lutécio/uso terapêutico , Linfoma de Células B/radioterapia , Radioimunoterapia/métodos , Radioisótopos/uso terapêutico , Anticorpos Monoclonais Murinos/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Humanos , Imunoconjugados/química , Índia , Lutécio/química , Radioisótopos/química , Rituximab
14.
ScientificWorldJournal ; 2014: 814109, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25485303

RESUMO

In this study, 108 P. multocida isolates recovered from various host animals such as cattle, buffalo, swine, poultry (chicken, duck, and emu) and rabbits were screened for carriage of 8 virulence associated genes. The results revealed some unique information on the prevalence of virulence associated genes among Indian isolates. With the exception of toxA gene, all other virulence associated genes were found to be regularly distributed among host species. Association study between capsule type and virulence genes suggested that pfhA, nanB, and nanH genes were regularly distributed among all serotypes with the exception of CapD, whereas toxA gene was found to be positively associated with CapD and CapA. The frequency of hgbA and nanH genes among swine isolates of Indian origin was found to be less in comparison to its equivalents around the globe. Interestingly, very high prevalence of tbpA gene was observed among poultry, swine, and rabbit isolates. Likewise, very high prevalence of pfhA gene (95.3%) was observed among Indian isolates, irrespective of host species origin.


Assuntos
Técnicas de Genotipagem/métodos , Interações Hospedeiro-Parasita/genética , Pasteurella multocida/genética , Pasteurella multocida/isolamento & purificação , Animais , Genes Bacterianos , Genótipo , Índia , Pasteurella multocida/patogenicidade , Virulência/genética
15.
ScientificWorldJournal ; 2014: 617034, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25587569

RESUMO

Identification of outer membrane proteins (OMPs) is important to understand the bacteria structure and function, host-pathogen interaction, development of novel vaccine candidates, and diagnostic antigens. But till now the key antigens of P. multocida B:2 isolate causing haemorrhagic septicaemia (HS) in animals are not clearly defined. In this study, P52 strain of P. multocida serotype B:2 was grown in vitro under iron-rich and iron-limited condition. The OMPs were extracted by sarkosyl method followed by SDS-PAGE and the proteins were identified by MALDI-TOF/MS analysis. In total, 22 proteins were identified, of which 7 were observed exclusively under iron-limited condition. Most of the high molecular weight proteins (TbpA, HgbA, HgbB, HasR, IroA, and HemR) identified in this study were involved in iron acquisition. Some hypothetical proteins (HP-KCU-10206, HP and AAUPMB 08244, HP AAUPMB 21592, HP AAUPMB 19766, AAUPMB 11295) were observed for the first time in this study which could be unique to serotype B:2. Further functional in vivo study of the proteins identified are required to explore the utility of these proteins in developing diagnostics and vaccine against HS.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Pasteurella multocida/classificação , Proteoma/metabolismo , Proteômica/métodos , Sorogrupo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Proteínas da Membrana Bacteriana Externa/imunologia , Western Blotting , Eletroforese em Gel de Poliacrilamida , Soros Imunes/imunologia , Epitopos Imunodominantes/imunologia , Índia , Ferro/farmacologia , Pasteurella multocida/efeitos dos fármacos
16.
J Nucl Med ; 65(1): 125-131, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37884334

RESUMO

Implementation of radiopharmaceutical therapy dosimetry varies depending on the clinical application, dosimetry protocol, software, and ultimately the operator. Assessing clinical dosimetry accuracy and precision is therefore a challenging task. This work emphasizes some pitfalls encountered during a structured analysis, performed on a single-patient dataset consisting of SPECT/CT images by various participants using a standard protocol and clinically approved commercial software. Methods: The clinical dataset consisted of the dosimetric study of a patient administered with [177Lu]Lu-DOTATATE at Tygerberg Hospital, South Africa, as a part of International Atomic Energy Agency-coordinated research project E23005. SPECT/CT images were acquired at 5 time points postinjection. Patient and calibration images were reconstructed on a workstation, and a calibration factor of 122.6 Bq/count was derived independently and provided to the participants. A standard dosimetric protocol was defined, and PLANETDose (version 3.1.1) software was installed at 9 centers to perform the dosimetry of 3 treatment cycles. The protocol included rigid image registration, segmentation (semimanual for organs, activity threshold for tumors), and dose voxel kernel convolution of activity followed by absorbed dose (AD) rate integration to obtain the ADs. Iterations of the protocol were performed by participants individually and within collective training, the results of which were analyzed for dosimetric variability, as well as for quality assurance and error analysis. Intermediary checkpoints were developed to understand possible sources of variation and to differentiate user error from legitimate user variability. Results: Initial dosimetric results for organs (liver and kidneys) and lesions showed considerable interoperator variability. Not only was the generation of intermediate checkpoints such as total counts, volumes, and activity required, but also activity-to-count ratio, activity concentration, and AD rate-to-activity concentration ratio to determine the source of variability. Conclusion: When the same patient dataset was analyzed using the same dosimetry procedure and software, significant disparities were observed in the results despite multiple sessions of training and feedback. Variations due to human error could be minimized or avoided by performing intensive training sessions, establishing intermediate checkpoints, conducting sanity checks, and cross-validating results across physicists or with standardized datasets. This finding promotes the development of quality assurance in clinical dosimetry.


Assuntos
Neoplasias , Compostos Radiofarmacêuticos , Humanos , Compostos Radiofarmacêuticos/uso terapêutico , Radiometria/métodos , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Fígado
17.
ACS Omega ; 8(33): 30459-30473, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37636912

RESUMO

Lanthanide (Ln3+)-doped upconversion (UC) phosphors converting near-infrared (NIR) light to visible light hold very high promise toward biomedical applications. The scientific findings on luminescent thermometers revealed their superiority for noninvasive thermal sensing. However, only few reports showcase their potential for applications in extreme conditions (temperatures below -70 °C) restricted by low thermal sensitivity. Here, we demonstrate the tailoring of luminescence properties via introducing Ho3+-Mn2+ energy transfer (ET) routes with judicious codoping of Mn2+ ions in ZnAl2O4/Ho3+,Yb3+ phosphor. Preferentially, a singular red UC emission is required to improve the bioimaging sensitivity and minimize tissue damage. We could attain UC emission with 94% red component by a two-photon UC process. Higher temperature annealing brings the color coordinates to the green domain, highlighting the potential for color-tunable luminescence switch. Moreover, this work investigates the thermometric properties of ZnAl2O4/Yb3+, Ho3+ in the range of 80-300 K and influence of inducing extra ET pathways by Mn2+ codoping. Interestingly, the luminescence intensities for nonthermally coupled (5F4,5S2) and the 5F5 radiative transitions of Ho3+ ions display opposite behavior at 80 and 300 K, which revealed competition between temperature-sensitive decay pathways. The codoping of Mn2+ ions is fruitful in causing a fourfold increase of absolute sensitivity. Notably, the color tunability from green through yellow to red is helpful in rough temperature estimation by naked eyes. The maximum relative (Sr) and absolute sensitivities (Sa) were estimated to be 1.89% K-1 (140 K) and 0.0734 K-1 (300 K), respectively. Even at 80 K, a Sa of 0.00447 K-1 and Sr of 0.6025% K-1 were achievable in our case, which are higher than most of the other Ln3+-based systems. The above-mentioned results demonstrate the potential of ZnAl2O4/Yb3+,Ho3+ for cryogenic optical thermometry and a strategy to design new Ln3+-based UC thermometers by taking advantage of ET routes.

18.
ACS Omega ; 8(36): 32444-32449, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37720751

RESUMO

Owing to the importance of heavy water in spectroscopy, nuclear energy generation, chemical characterization, and biological industry, a design of a robust, cheap, nontoxic, and sensitive D2O sensor is very important. In this work, taking advantage of the singular emission fluorescence of the deep eutectic solvent prepared in our laboratory, we propose a first of its kind highly sensitive turn-on fluorescent sensor to effectively sense D2O at an ultratrace level based on rapid exchange of the labile DES proton with deuterium. This method can be used as a full-range heavy water detection strategy with a limit of detection of 0.079% (v/v) or 870 ppm. The isotopic purity (IP) obtained from DES fluorescence measurements is also in close agreement with that of the conventional FT-IR method. The current DES-based sensor thus allows both sensing and isotopic purity of D2O and can serve as one of the most sensitive monitoring strategies for heavy water analysis.

19.
Protoplasma ; 260(5): 1437-1451, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37131068

RESUMO

Chickpea is considered recalcitrant to in vitro tissue culture amongst all edible legumes. The clustered, regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9)-based genome editing in chickpea can remove the bottleneck of limited genetic variation in this cash crop, which is rich in nutrients and protein. However, generating stable mutant lines using CRISPR/Cas9 requires efficient and highly reproducible transformation protocols. As an attempt to solve this problem, we developed a modified and optimized protocol for chickpea transformation. This study transformed the single cotyledon half-embryo explants using CaMV35S promoter to drive two marker genes (ß-glucuronidase gene; GUS and green fluorescent protein; GFP) through binary vectors pBI101.2 and modified pGWB2, respectively. These vectors were delivered in the explants through three different strains of Agrobacterium tumefaciens, viz., GV3101, EHA105, and LBA4404. We found better efficiency with the strain GV3101 (17.56%) compared with two other strains, i.e., 8.54 and 5.43%, respectively. We recorded better regeneration frequencies in plant tissue culture for the constructs GUS and GFP, i.e., 20.54% and 18.09%, respectively. The GV3101 was further used for the transformation of the genome editing construct. For the development of genome-edited plants, we used this modified protocol. We also used a modified binary vector pPZP200 by introducing a CaMV35S-driven chickpea codon-optimized SpCas9 gene. The promoter of the Medicago truncatula U6.1 snRNA gene was used to drive the guide RNA cassettes. This cassette targeted and edited the chickpea phytoene desaturase (CaPDS) gene. A single gRNA was found sufficient to achieve high efficiency (42%) editing with the generation of PDS mutants with albino phenotypes. A simple, rapid, highly reproducible, stable transformation and CRISPR/Cas9-based genome editing system for chickpea was established. This study aimed to demonstrate this system's applicability by performing a gene knockout of the chickpea PDS gene using an improved chickpea transformation protocol for the first time.


Assuntos
Cicer , Edição de Genes , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Cicer/genética , Códon , Agrobacterium tumefaciens , Genoma de Planta/genética
20.
Front Genet ; 14: 1085024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37144131

RESUMO

Genomics and genome editing promise enormous opportunities for crop improvement and elementary research. Precise modification in the specific targeted location of a genome has profited over the unplanned insertional events which are generally accomplished employing unadventurous means of genetic modifications. The advent of new genome editing procedures viz; zinc finger nucleases (ZFNs), homing endonucleases, transcription activator like effector nucleases (TALENs), Base Editors (BEs), and Primer Editors (PEs) enable molecular scientists to modulate gene expressions or create novel genes with high precision and efficiency. However, all these techniques are exorbitant and tedious since their prerequisites are difficult processes that necessitate protein engineering. Contrary to first generation genome modifying methods, CRISPR/Cas9 is simple to construct, and clones can hypothetically target several locations in the genome with different guide RNAs. Following the model of the application in crop with the help of the CRISPR/Cas9 module, various customized Cas9 cassettes have been cast off to advance mark discrimination and diminish random cuts. The present study discusses the progression in genome editing apparatuses, and their applications in chickpea crop development, scientific limitations, and future perspectives for biofortifying cytokinin dehydrogenase, nitrate reductase, superoxide dismutase to induce drought resistance, heat tolerance and higher yield in chickpea to encounter global climate change, hunger and nutritional threats.

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