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1.
Chemistry ; 29(32): e202300563, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-36971616

RESUMO

We report the functionalization and deplanarization of truxenes using pnictaalkene fragments. Selective introduction of one, two, or three Mes*-Pn fragments provides up to three fully reversible reductions based on the Pn=C fragments. The incorporation of the unsaturated heteroelement fragment as well as the contortion of the truxene core result in significantly red-shifted absorption spectra and interesting opto-electronic properties which are studied by electrochemistry and spectro-electrochemistry. Incorporation of arsaalkene (As=C) motifs gives significantly milder reduction potentials and red-shifted absorption, while phosphaalkene decorated truxene P3 can be functionalized using Au(I)Cl coordination. Furthermore, solubility is markedly increased upon incorporation of the Pn-Mes* fragments which renders these materials suitable for solution processing.


Assuntos
Eletrônica , Elétrons , Estrutura Molecular , Solubilidade
2.
Angew Chem Int Ed Engl ; 61(4): e202114132, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34797935

RESUMO

Energy-efficient selective physisorption driven C2 H2 separation from industrial C2-C1 impurities such as C2 H4 , CO2 and CH4 is of great importance in the purification of downstream commodity chemicals. We address this challenge employing a series of isoreticular cationic metal-organic frameworks, namely iMOF-nC (n=5, 6, 7). All three square lattice topology MOFs registered higher C2 H2 uptakes versus the competing C2-C1 gases (C2 H4 , CO2 and CH4 ). Dynamic column breakthrough experiments on the best-performing iMOF-6C revealed the first three-in-one C2 H2 adsorption selectivity guided separation of C2 H2 from 1:1 C2 H2 /CO2 , C2 H2 /C2 H4 and C2 H2 /CH4 mixtures. Density functional theory calculations critically examined the C2 H2 selective interactions in iMOF-6C. Thanks to the abundance of square lattice topology MOFs, this study introduces a crystal engineering blueprint for designing C2 H2 -selective layered metal-organic physisorbents, previously unreported in cationic frameworks.

3.
Anal Chem ; 93(2): 1193-1199, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33289388

RESUMO

We have explored a novel turn-on fluorescence detection of sulfur mustard (SM) at "room temperature". The innovative protocol that uses the combination of luminol and an ionic liquid in water exhibits fluorescence detection of SM within seconds. In this simple, fast, and low-cost chemosensing method, luminol acts as the receptor as well as a signaling element, and the ionic liquid (1-ethyl-3-methylimidazolium dicyanamide) provides the requisite and polarizing medium to realize the detection at "room temperature". Interestingly, with a higher concentration of a probe (0.56 mM), SM sensing can be visualized with the naked eye, leading to the formation of a fluorescent green color within a minute, thus expanding the application of the developed sensing technique for chromo-fluorogenic detection of SM. Excellent selectivity, sensitivity (LOD: 6 ppm), and chemosensing at ambient temperature make this methodology completely field-deployable.


Assuntos
Corantes Fluorescentes/química , Luminol/química , Gás de Mostarda/análise , Temperatura , Estrutura Molecular , Espectrometria de Fluorescência
4.
Inorg Chem ; 60(12): 8973-8983, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34081458

RESUMO

The hierarchical self-organization of structurally complex high-nuclearity metal clusters with metallosupramolecular wheel architectures that are obtained from the self-assembly of smaller solvated cluster units is rare and unique. Here, we use the potentially heteroditopic monothiocarbonate ligand and demonstrate for the first time the synthesis and structure of a solvated non-cyclic hexadecanuclear cluster [Cu{SC(O)OiPr}]16·2THF (1) that can simultaneously desolvate and self-assemble in solution and subsequently form a giant metallaring, [Cu{SC(O)OiPr}]96 (2). We also demonstrate a luminescent precursor to cluster (2) can be achieved through a solventless and rapid mechanochemical synthesis. Cluster (2) is the highest nuclearity copper(I) wheel and the largest metal cluster containing a heterodichalcogen (O, S) ligand reported to date. Cluster (2) also exhibits solid-state luminescence with relatively long emission lifetimes at 4.1, 13.9 (µs). The synthetic strategy described here opens new research avenues by replacing solvent molecules in stable {Cu16} clusters with designed building units that can form new hybrid and multifunctional finite supramolecular materials. This finding may lead to the development of novel high-nuclearity materials self-assembled in a facile manner with tunable optical properties.

5.
J Am Chem Soc ; 142(25): 10942-10954, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32456426

RESUMO

Benzene exhibits a rich photochemistry which can provide access to complex molecular scaffolds that are difficult to access with reactions in the electronic ground state. While benzene is aromatic in its ground state, it is antiaromatic in its lowest ππ* excited states. Herein, we clarify to what extent relief of excited-state antiaromaticity (ESAA) triggers a fundamental benzene photoreaction: the photoinitiated nucleophilic addition of solvent to benzene in acidic media leading to substituted bicyclo[3.1.0]hex-2-enes. The reaction scope was probed experimentally, and it was found that silyl-substituted benzenes provide the most rapid access to bicyclo[3.1.0]hexene derivatives, formed as single isomers with three stereogenic centers in yields up to 75% in one step. Two major mechanism hypotheses, both involving ESAA relief, were explored through quantum chemical calculations and experiments. The first mechanism involves protonation of excited-state benzene and subsequent rearrangement to bicyclo[3.1.0]hexenium cation, trapped by a nucleophile, while the second involves photorearrangement of benzene to benzvalene followed by protonation and nucleophilic addition. Our studies reveal that the second mechanism is operative. We also clarify that similar ESAA relief leads to puckering of S1-state silabenzene and pyridinium ion, where the photorearrangement of the latter is of established synthetic utility. Finally, we identified causes for the limitations of the reaction, information that should be valuable in explorations of similar photoreactions. Taken together, we reveal how the ESAA in benzene and 6π-electron heterocycles trigger photochemical distortions that provide access to complex three-dimensional molecular scaffolds from simple reactants.

6.
J Am Chem Soc ; 141(40): 15942-15950, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31508946

RESUMO

Molecular hydrogen evolution catalysts (HECs) are synthetically tunable and often exhibit high activity, but they are also hampered by stability concerns and practical limitations associated with their use in the homogeneous phase. Their incorporation as integral linker units in metal-organic frameworks (MOFs) can remedy these shortcomings. Moreover, the extended three-dimensional structure of MOFs gives rise to high catalyst loadings per geometric surface area. Herein, we report a new MOF that exclusively consists of cobaloximes, a widely studied HEC, that act as metallo-linkers between hexanuclear zirconium clusters. When grown on conducting substrates and under applied reductive potential, the cobaloxime linkers promote electron transport through the film as well as function as molecular HECs. The obtained turnover numbers are orders of magnitude higher than those of any other comparable cobaloxime system, and the molecular integrity of the cobaloxime catalysts is maintained for at least 18 h of electrocatalysis. Being one of the very few hydrogen evolving electrocatalytic MOFs based on a redox-active metallo-linker, this work explores uncharted terrain for greater catalyst diversity and charge transport pathways.

7.
Nucleic Acids Res ; 45(16): 9760-9772, 2017 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-28934483

RESUMO

Extra-cytoplasmic function (ECF) σ-factors are widespread in bacteria, linking environmental stimuli with changes in gene expression. These transcription factors span several phylogenetically distinct groups and are remarkably diverse in their activation and regulatory mechanisms. Here, we describe the structural and biochemical features of a Mycobacterium tuberculosis ECF factor σJ that suggests that the SnoaL_2 domain at the C-terminus can modulate the activity of this initiation factor in the absence of a cognate regulatory anti-σ factor. M. tuberculosis σJ can bind promoter DNA in vitro; this interaction is substantially impaired by the removal of the SnoaL_2 domain. This finding is consistent with assays to evaluate σJ-mediated gene expression. Structural similarity of the SnoaL_2 domain with epoxide hydrolases also suggests a novel functional role for this domain. The conserved sequence features between M. tuberculosis σJ and other members of the ECF41 family of σ-factors suggest that the regulatory mechanism involving the C-terminal SnoaL_2 domain is likely to be retained in this family of proteins. These studies suggest that the ECF41 family of σ-factors incorporate features of both-the σ70 family and bacterial one-component systems thereby providing a direct mechanism to implement environment-mediated transcription changes.


Assuntos
Mycobacterium tuberculosis/genética , Regiões Promotoras Genéticas , Fator sigma/química , Fator sigma/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cristalografia por Raios X , Simulação de Dinâmica Molecular , Conformação Proteica , Domínios Proteicos , Fator sigma/genética , Ressonância de Plasmônio de Superfície , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
8.
Anal Chem ; 90(2): 1417-1422, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29300079

RESUMO

Since the first use of chemical warfare agents (CWA) (1915) to the recent attacks in Syria (2017) on mankind, there have been many incidents where CWA have claimed thousands of lives and left many more contaminated. In order to provide the appropriate and immediate medical counter measure to the victims, the exact classification of these chemical agents within few minutes on the field itself using a rapid and simple detection technique is extremely important to save the lives of the effected people. This has motivated all of us to explore the novel strategies/detection systems that can be field deployable with better selectivity and greater sensitivity. In view of this, we present a novel chemosensor, 3,6-bis(dimethylamino)-9(10H)-acridine thione (1), that can detect mustard gas and its simulant by both chromogenic and fluorogenic methods. For the first time, a single probe was able to demonstrate the detection with unprecedented selectivity over most probable interferences (nerve agents and alkylating agents) including solvents, acids, and bases which are routinely present in the environment. The desired level of sensitivity by naked eyes (0.04 mg/mL), UV spectroscopy (0.02 mg/mL), and fluorescence spectroscopy (0.005 mg/mL) makes this method truly field deployable. For the spot detection on the affected areas, a handy and potable chemosensor kit was also fabricated. This paper provides a simple, highly specific, and easy to use method in "actual sense" that not only detects the agents in the solution phase but also in the contaminated samples.


Assuntos
Substâncias para a Guerra Química/análise , Corantes/química , Poluentes Ambientais/análise , Gás de Mostarda/análise , Tionas/química , Colorimetria/métodos , Corantes Fluorescentes/química , Poluentes do Solo/análise , Espectrometria de Fluorescência/métodos , Espectrofotometria Ultravioleta/métodos
9.
Chemistry ; 23(72): 18296-18302, 2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-29076576

RESUMO

Structural transformations of supramolecular assemblies play an important role in the synthesis of complex metal-organic materials. Nonetheless, often little is known of the assembly pathways that lead to the final product. This work describes the conversion of cubic metal-organic polyhedra to connected-cage networks of varying topologies. The neutral cubic cage assembly of formula {Pd3 [PO(NiPr)3 ]}8 (PZDC)12 has been synthesized from {Pd3 [(NiPr)3 PO](OAc)2 (OH)}2 ⋅2 (CH3 )2 SO and 2,5-pyrazenedicarboxilic acid (PZDC-2H). This 42-component self-assembly is the largest known among the neutral cages with PdII ions. The cage contains twenty-four vacant carboxylate O-sites at the PZDC ligands that are available for further coordination. Post-assembly reactions of the cubic cage with FeII and ZnII ions produced cage-connected networks of dia and qtz topologies, respectively. During these reactions, the discrete cubic cage transforms into a network of tetrahedral cages that are bridged by the 3D metal ions. The robustness of the [Pd3 {[PO(NiPr)3 }]3+ molecular building units made it possible to map the post-assembly reactions in detail, which revealed a variety of intermediate 1D and 2D cage networks. Such step-by-step mapping of the transformation of discrete cages to cage-connected frameworks is unprecedented in the chemistry of coordination driven assemblies.

10.
Inorg Chem ; 54(7): 3196-202, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25781912

RESUMO

A charge-neutral tetrahedral [(Pd3X)4L6] cage assembly built from a trinuclear polyhedral building unit (PBU), [Pd3X](3+), cis-blocked with an imido P(V) ligand, [(N(i)Pr)3PO](3-) (X(3-)), and oxalate dianions (L(2-)) is reported. Use of benzoate or ferrocene dicarboxylate anions, which do not offer wide-angle chelation as that of oxalate dianions, leads to smaller prismatic clusters instead of polyhedral cage assemblies. The porosity of the tetrahedral cage assembly was determined by gas adsorption studies, which show a higher uptake capacity for CO2 over N2 and H2. The tetrahedral cage was shown to encapsulate a wide range of neutral guest solvents from polar to nonpolar such as dimethyl sulfoxide, benzene, dichloromethane, chloroform, carbon tetrachloride, and cyclopentane as observed by mass spectral and single-crystal X-ray diffraction studies. The (1)H two-dimensional diffusion ordered spectroscopy NMR analysis shows that the host and guest molecules exhibit similar diffusion coefficients in all the studied host-guest systems. Further, the tetrahedral cage shows selective binding of benzene, CCl4, and cyclopentane among other solvents from their categories as evidenced from mass spectral analysis. A preliminary density functional theory analysis gave a highest binding energy for benzene among the other solvents that were structurally shown to be encapsulated at the intrinsic cavity of the tetrahedral cage.


Assuntos
Modelos Moleculares , Paládio/química , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Simulação de Dinâmica Molecular
11.
Inorg Chem ; 52(13): 7608-14, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23750700

RESUMO

Employing Pd(OAc)2, a facile deprotonation route to access the highly basic tris(alkylimido)phosphate trianions, [(RN)3PO](3-) (R = (t)Bu, (c)Hex, or (i)Pr), analogous to the orthophosphate (PO4(3-)) ion in polar and in protic solvents has been achieved. Trinuclear and prismatic Pd(II) clusters of these imido trianions having the formula {Pd3[(NR)3PO](OAc)3}n (n = 1 or 2) or as mixed-bridged clusters of the type {Pd3[(N(i)Pr)3PO](OAc)2(OR')}2 (R' = Me or H) were isolated exclusively in all these reactions in which the trianionic species acts as a tripodal chelating ligand to the trinuclear Pd3 unit. Reactivity studies aiming at the Pd(II) atoms in these clusters with nucleophilic reagents, such as primary amines (R″NH2), have led to a new trimeric cluster with the formula {Pd3[(NR)3PO](OAc)3(R″NH2)3} in which the tripodal coordination of the Pd-Nimido moieties remained unaffected, exemplifying the robustness of the Pd3 unit in all these clusters. We have also shown the catalytic activity of these Pd(II) complexes in Mizoroki-Heck type coupling reactions in the presence of Cu(OAc)2.

12.
J Family Med Prim Care ; 12(7): 1460-1463, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37649755

RESUMO

Chronic myeloid leukemia (CML) patients frequently exhibit systemic symptoms such as fatigue, abdominal discomfort, weight loss, and fever but rarely can have atypical initial presentation in the form of ophthalmic manifestations, which can precede the diagnosis of the primary malignancy. We describe a case of a 29-year-old male who presented in our ophthalmology out-patient department (OPD) with complaints of painless, diminution of vision, which was sudden in onset in right eye (RE) and loss of vision in left eye (LE) for four and seven days, respectively. There had been a history of loss of weight and appetite for the past 2 months. The visual acuity (VA) recorded was finger counting two meters in RE and perception of light in LE with an inaccurate projection of rays in both eyes (BE). The anterior segment evaluation of both eyes (BE) was normal. Fundus revealed multiple elevated yellow subretinal lesions with exudative detachment in the RE and no view in the LE. Ultrasound-Brightness (USG B) scan in the LE revealed multiple hyperreflective echoes likely vitreous hemorrhage. Optical coherence tomography (OCT) showed subretinal hyperreflectivity with surrounding edema in RE suggestive of leukemic infiltrates. On further systemic investigations, chronic myeloid leukemia-chronic phase (CML-CP) was detected; hence, the diagnosis of RE exudative retinal detachment (RD) and LE vitreous hemorrhage with CML-CP was made. Ophthalmic involvement is more often seen in acute than chronic leukemia, which makes the diagnosis challenging. We describe a unique case of a young patient with CML-CP who initially presented with ocular involvement preceding systemic diagnosis. This case report illustrates the importance of a primary care physician or an ophthalmologist in the early diagnosis and prompt management of hematological malignancy, as ophthalmic manifestations may be a rare initial presenting feature in CML-CP. These conditions require urgent referral to a hematologist by a primary care physician in the view of early commencement of therapy.

13.
Cureus ; 15(6): e40667, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37485171

RESUMO

INTRODUCTION: Thalassemia and hemoglobinopathies are the most common inherited hematological disorders. Of these, ß thalassemia is the commonest disorder reported in India, followed by certain hemoglobinopathies encountered in different regions of the country. The data pertaining to the incidence of these disorders in the Uttarakhand region of India are sparse. AIM AND OBJECTIVES: To ascertain the prevalence and spectrum of thalassemia/hemoglobinopathies amongst antenatal women in Uttarakhand. The study also aimed to analyze the ability of red cell indices in differentiating beta thalassemia trait (BTT) from mild iron deficiency anemia (IDA). MATERIAL AND METHODS: A total of 460 pregnant women in the first trimester of pregnancy were screened by cation exchange high-performance liquid chromatography. Retention time and proportions of normal/abnormal hemoglobin peaks were documented in all cases. Hemoglobin A2 (HbA2) values of ≥4% were taken as a cut-off for diagnosing BTT. Blood samples were also collected for complete blood counts, reticulocyte counts, and serum ferritin. The ability of the various discriminatory indices to differentiate between IDA and BTT was also assessed. RESULTS: The prevalence of BTT and hemoglobin D-Punjab trait amongst pregnant women was found to be 2.6% and 0.2%, respectively. RBC count, mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) were found to be moderately strong predictors of BTT, with an area under the curve of 0.860, 0.857, and 0.842, respectively, which were comparable to the discriminatory indices found to be most useful in this study. CONCLUSION: In view of the 2.6% prevalence of BTT in antenatal women in this region of Uttarakhand, a routine screening will be helpful in detecting carriers early in the antenatal period. Careful interpretation of red cell indices is crucial to the distinction between BTT and IDA. Discriminatory indices are reasonably accurate in differentiating BTT from mild iron deficiency, but for practical purposes, MCV and MCH provide equivalent information to identify cases that require further workup.

14.
J Cancer Res Ther ; 19(5): 1335-1339, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37787304

RESUMO

Background: Leukemic cells express a characteristic set of "cluster of differentiation" (CD) markers, which forms the basis of the current WHO classification. Leukemia-associated aberrant immunophenotype (LAIP) refers to expression of unusual CD markers by leukemic cells, which are not normally expressed by their respective lineage. The incidence of LAIP varies considerably, and its clinical implications, prognostic relevance, and sensitivity to therapy are still debatable. This study was conducted to identify the immunophenotypic aberrancies in newly diagnosed leukemias in our Institute. Method: This was an observational study, which included newly diagnosed leukemias on flow cytometry. Aberrant immunophenotypic expressions were recorded whenever present and were correlated with prognostic factors like age, gender, and total leucocyte count (TLC). Results: The study included 110 newly diagnosed cases of leukemias (85 acute and 25 chronic) over 1.5 years. Immunophenotypic aberrancies were detected in 40.4% of the cases. The highest incidence of aberrations was detected in acute myeloid leukemia (60.7%). LAIPs were detected in 50% of T-acute lymphoblastic leukemia and 25% cases of in B-cell acute lymphoblastic leukemia (B-ALL). Aberrant CD33 and CD56 expression in B-ALL correlated with poor prognostic factors like higher age and higher TLC, respectively. Immunophenotypic aberrancies were present in 28% cases of chronic lymphocytic leukemia. Conclusion: The results of this study have generated valuable baseline data on the incidence of LAIPs in this region. This information is vital because establishing LAIPs at the time of diagnosis is crucial for disease monitoring. Some LAIPs are associated with underlying cytogenetic abnormalities and hence impact the management and prognosis.


Assuntos
Leucemia Linfocítica Crônica de Células B , Leucemia Mieloide Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Citometria de Fluxo/métodos , Centros de Atenção Terciária , Leucemia Mieloide Aguda/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Imunofenotipagem
15.
Indian J Occup Environ Med ; 25(2): 119-124, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421250

RESUMO

BACKGROUND: Strategic, operational and tactical superiority of Navy hinges on extremely efficient warships which in turn depend on professionally competent sailors ready to undertake tasks to deliver timely, structured and metered response. Ships and their potentialities are tools to achieve the required strategic advantage which is dependent on the proficiency of sailors. Sailors who are fit ashore may be debilitated on board because of sea sickness. AIMS: To study the incidence and severity of sea sickness among 500 naval personnel from various ships. Setting and design: An observational study conducted from May 2019 to March 2020 among 500 naval personnel from various ships of the fleet. MATERIALS AND METHODS: Motion Sickness Assessment Questionnaire (MSAQ) was used to collect data from personnel of different departments working in different part of ship aged between 20 to 50 years. RESULTS: The majority suffered mild symptoms (78.78%) and did not require any medication. Their symptoms were selflimiting and settled on rest within 24 hours. Moderately severe symptoms were observed among 19.31 % personnel and had to be administered medication and rest for 24 hours. Only 1.91% had severe symptoms and had to be excused from duties along with medication and rest. CONCLUSION: Sea sickness is unpleasant and has an adverse effect on employability of the sailors. It is mild and self limiting in majority of the personnel not requiring active intervention. Some personnel may require desensitisation along with pharmacotherapy.

16.
Dalton Trans ; 50(2): 660-674, 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33325945

RESUMO

Developing new transition metal catalysts requires understanding of how both metal and ligand properties determine reactivity. Since metal complexes bearing ligands of the Py5 family (2,6-bis-[(2-pyridyl)methyl]pyridine) have been employed in many fields in the past 20 years, we set out here to understand their redox properties by studying a series of base metal ions (M = Mn, Fe, Co, and Ni) within the Py5OH (pyridine-2,6-diylbis[di-(pyridin-2-yl)methanol]) variant. Both reduced (MII) and the one-electron oxidized (MIII) species were carefully characterized using a combination of X-ray crystallography, X-ray absorption spectroscopy, cyclic voltammetry, and density-functional theory calculations. The observed metal-ligand interactions and electrochemical properties do not always follow consistent trends along the periodic table. We demonstrate that this observation cannot be explained by only considering orbital and geometric relaxation, and that spin multiplicity changes needed to be included into the DFT calculations to reproduce and understand these trends. In addition, exchange reactions of the sixth ligand coordinated to the metal, were analysed. Finally, by including published data of the extensively characterised Py5OMe (pyridine-2,6-diylbis[di-(pyridin-2-yl)methoxymethane])complexes, the special characteristics of the less common Py5OH ligand were extracted. This comparison highlights the non-innocent effect of the distal OH functionalization on the geometry, and consequently on the electronic structure of the metal complexes. Together, this gives a complete analysis of metal and ligand degrees of freedom for these base metal complexes, while also providing general insights into how to control electrochemical processes of transition metal complexes.

17.
J Family Med Prim Care ; 8(12): 3931-3934, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31879638

RESUMO

BACKGROUND: The surge of the geriatric population has led to design research studies related to health problems in this age group worldwide. Bone marrow examination which is an important diagnostic tool for various diseases may vary in geriatric population in comparison to younger groups. The present study was, therefore, conducted to study the indications and morphological features of bone marrow examination in geriatric population in north Himalayan region of India. It was also intended to study if there is any variation in these findings from elderly populations in other parts of the world. MATERIAL AND METHODS: Study was conducted in an institute situated in north Himalayan Uttarakhand state of India over a period of two years including patients above 60 years of age who underwent bone marrow examination. RESULTS: Total 156 cases underwent bone marrow examination with most common indication being suspicion of lymphoma (18.5%) followed by cytopenia (17.3%). Nutritional anaemia was most common pathological diagnosis in 16.6% cases. Diagnostic discordance between aspirate and biopsy was observed in 5.7% of total cases with non-Hodgkin's lymphoma (NHL) being the most common misdiagnosis on aspirate. CONCLUSION: Nutritional anaemia particularly iron deficiency anaemia is the most common diagnosis of bone marrow examination indicating the importance of nutritional therapy in the elderly population of this region. Bone marrow biopsy proves to be an important adjunct to aspiration in precise diagnosis with minimal complications. The awareness of bone marrow findings would not only be helpful to clinicians and pathologists but also provide valuable information to the policymakers to improve the quality of health in the geriatric population of this area.

18.
J Family Med Prim Care ; 8(12): 3944-3948, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31879641

RESUMO

BACKGROUND: Pancytopenia, an important hematological presentation is associated with different causes, which may vary in different regions. Uttarakhand, a north Himalayan state of India lacks studies of pancytopenia and the prevalent causes present in this region. Therefore, the present study was conducted to study the clinico-hematological profile of pancytopenia in a tertiary care center in the Uttarakhand, a north Himalayan state of India. It was also intended to study if these causes showed any variation from other studies done in different regions of India. MATERIALS AND METHODS: The present observational study was conducted in a tertiary care institute situated in Uttarakhand state of India over a period of 1 year and 8 month from June 2017 to Feb 2019 including all the cases of pancytopenia. RESULTS: The most common cause of pancytopenia was megaloblastic anemia (25%), followed by aleukemic leukemia and hypoplastic/aplastic anemia (19.1% each). Visceral leishmaniasis also constituted an important cause of pancytopenia in this study (11.7%). CONCLUSION: The study concludes that megaloblastic anemia and aleukemic leukemia are the most common cause of pancytopenia. Although leishmaniasis is considered to be non-endemic in this region, it constitutes an important cause of pancytopenia here. The clinicians, especially the physicians practicing the primary care and pathologists, should be aware of the different causes of pancytopenia present in this Himalayan region of India; therefore, delay in diagnosis can be prevented along with unnecessary investigations.

19.
Genome Announc ; 6(26)2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-29954890

RESUMO

Maize bacterial leaf streak disease has spread across maize crops in South Africa and therefore potentially poses a threat to maize production and food security. Until recently, this pathogen was identified as a Xanthomonas campestris pathovar, whereas our South African genomes seem to be more divergent and create their own subclade.

20.
Molecules ; 12(9): 2193-200, 2007 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17962736

RESUMO

A novel and efficient method has been developed for the synthesis of N,N-dialkylamino-O-alkyl-2-(1-methyl-2-oxopropylidene)phosphorohydrazido oximes 5. The reactions involve the condensation of diacetylmonoxime and N,N-dialkylamino-O- alkylphosphorohydrazides in the presence of activated silica and give the corresponding target oximes in excellent yields under mild conditions.


Assuntos
Hidrazinas/síntese química , Compostos Organofosforados/síntese química , Oximas/síntese química , Hidrazinas/química , Espectroscopia de Ressonância Magnética , Compostos Organofosforados/química , Oximas/química , Isótopos de Fósforo
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