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1.
Int Ophthalmol ; 41(8): 2765-2775, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33830371

RESUMO

AIM: To study frequency and characteristics of ocular manifestations in Indian patients with collagen vascular disorders. METHODS: The medical records of 73 patients (Males: Females 16:57) aged between 22 and 78 years (mean ± SD = 43.5 ± 12.9 years) with collagen vascular diseases were analyzed retrospectively for demography, subtypes of collagen vascular disease, and findings of complete ophthalmic examination. RESULTS: Lupus erythematosus (LE) in 39(53.4%, (SLE 18, DLE 21), systemic sclerosis in 27(37%), dermatomyositis in 5(6.8%), and primary Sjögren's syndrome in 2(2.7%) patients, respectively, were observed. Only 35(47.9%) patients had ocular manifestations. In LE keratoconjunctivitis sicca (n = 6), keratitis (n = 5), severe blepharitis (n = 3), retinopathy (n = 2), and optic neuritis in one patient, respectively, were major ocular manifestations. Major abnormalities occurring in systemic sclerosis included restricted eyelid mobility of variable severity (n = 8), eyelid telangiectasia (n = 5), keratoconjunctivitis sicca (n = 6), cataract (n = 5), shallow fornices (n = 4), conjunctival surface disease (n = 4), and uveitis, keratitis, episcleritis in one patient each, respectively. One patient with dermatomyositis had heliotrope rash. Two patients with primary Sjögren's syndrome had keratoconjunctivitis sicca. CONCLUSIONS: The study shows that LE frequently presented with keratoconjunctivitis sicca, retinopathy, and optic neuritis. Systemic sclerosis commonly develops eyelid immobility, blepharitis and telangiectasia, ocular surface disease and keratoconjunctivitis sicca, corneal abnormalities, and uveitis. A comprehensive ocular evaluation is imperative for early detection and management particularly of ocular surface disease, uveitis, and retinopathy to prevent potential sight-threatening complications. Limitations include retrospective study design and small number of patients for stratification.


Assuntos
Oftalmopatias/etiologia , Lúpus Eritematoso Sistêmico , Síndrome de Sjogren , Adulto , Idoso , Colágeno , Feminino , Hospitais , Humanos , Lúpus Eritematoso Sistêmico/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Síndrome de Sjogren/complicações , Adulto Jovem
2.
Phys Rev Lett ; 125(21): 215702, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33274960

RESUMO

Despite extensive shock wave and static compression experiments and corresponding theoretical work, consensus on the crystal structure and the melt boundary of Fe at Earth's core conditions is lacking. We present in situ x-ray diffraction measurements in laser-shock compressed Fe that establish the stability of the hexagonal-close-packed (hcp) structure along the Hugoniot through shock melting, which occurs between ∼242 to ∼247 GPa. Using previously reported hcp Fe Hugoniot temperatures, the melt temperature is estimated to be 5560(360) K at 242 GPa, consistent with several reported Fe melt curves. Extrapolation of this value suggests ∼6400 K melt temperature at Earth's inner core boundary pressure.

3.
Phys Rev Lett ; 124(23): 235701, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32603153

RESUMO

High pressure structural transformations are typically characterized by the thermodynamic state (pressure-volume-temperature) of the material. We present in situ x-ray diffraction measurements on laser-shock compressed silver and platinum to determine the role of deformation-induced lattice defects on high pressure phase transformations in noble metals. Results for shocked Ag show a copious increase in stacking faults (SFs) before transformation to the body-centered-cubic (bcc) structure at 144-158 GPa. In contrast, shock compressed Pt remains largely free of SFs and retains the fcc structure to over 380 GPa. These findings, along with recent results for shock compressed gold, show that SF formation promotes high pressure structural transformations in shocked noble metals that are not observed under static compression. Potential SF-related mechanisms for fcc-bcc transformations are discussed.

4.
Phys Rev Lett ; 123(4): 045702, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31491271

RESUMO

Gold is believed to retain its ambient crystal structure at very high pressures under static and shock compression, enabling its wide use as a pressure marker. Our in situ x-ray diffraction measurements on shock-compressed gold show that it transforms to the body-centered-cubic (bcc) phase, with an onset pressure between 150 and 176 GPa. A liquid-bcc coexistence was observed between 220 and 302 GPa and complete melting occurs by 355 GPa. Our observation of the lower coordination bcc structure in shocked gold is in marked contrast to theoretical predictions and the reported observation of the hexagonal-close-packed structure under static compression.

5.
Physiol Mol Biol Plants ; 25(1): 159-166, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30804638

RESUMO

In this study, the effect of gamma irradiation in inducing resistance/tolerance towards powdery mildew disease was investigated in Gerbera jamesonii cv. 'Harley'. In vitro shoot cultures were established through capitulum explants on Murashige and Skoog medium supplemented with 22.2 µM 6-benzyladenine (BA) and 2.53 µM indole acetic acid (IAA), followed by gamma irradiation of regenerated shoots (3-5 cm). Activity of four antioxidant enzymes i.e. superoxide dismutase, ascorbate peroxidase, catalase and glutathione reductase increased significantly as compared to the control and reached to highest level at the most stringent doses of mutagen. Ninety randomly selected irradiated plants (6 months old) and 100 control plants were inoculated with fungal conidial suspension, to screen for tolerance/resistance against powdery mildew. The severity of the disease was recorded on 0-4 scale with '0' indicating highly resistant; '1' indicating resistant; '2' indicating medium resistance; '3' indicating susceptible and '4' indicating highly susceptible. Three plants (3.33%) irradiated with 5 Gy were found to be tolerant to powdery mildew as these plants showed slight and delayed development of fungal colonies on the leaves. The random amplified polymorphic DNA characterization showed that the irradiated plants had DNA patterns that were different from the control and mother plants.

6.
Phys Rev Lett ; 121(13): 135701, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30312076

RESUMO

In situ, time-resolved, x-ray diffraction and simultaneous continuum measurements were used to examine structural changes in Si shock compressed to 54 GPa. Shock melting was unambiguously established above ∼31-33 GPa, through the vanishing of all sharp crystalline diffraction peaks and the emergence of a single broad diffraction ring. Reshock from the melt boundary results in rapid (nanosecond) recrystallization to the hexagonal-close-packed Si phase and further supports melting. Our results also provide new constraints on the high-temperature, high-pressure Si phase diagram.

7.
Cancer Immunol Immunother ; 66(11): 1425-1436, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28660319

RESUMO

The primary aim of this clinical trial was to determine the feasibility of delivering first-generation CAR T cell therapy to patients with advanced, CEACAM5+ malignancy. Secondary aims were to assess clinical efficacy, immune effector function and optimal dose of CAR T cells. Three cohorts of patients received increasing doses of CEACAM5+-specific CAR T cells after fludarabine pre-conditioning plus systemic IL2 support post T cell infusion. Patients in cohort 4 received increased intensity pre-conditioning (cyclophosphamide and fludarabine), systemic IL2 support and CAR T cells. No objective clinical responses were observed. CAR T cell engraftment in patients within cohort 4 was significantly higher. However, engraftment was short-lived with a rapid decline of systemic CAR T cells within 14 days. Patients in cohort 4 had transient, acute respiratory toxicity which, in combination with lack of prolonged CAR T cell persistence, resulted in the premature closure of the trial. Elevated levels of systemic IFNγ and IL-6 implied that the CEACAM5-specific T cells had undergone immune activation in vivo but only in patients receiving high-intensity pre-conditioning. Expression of CEACAM5 on lung epithelium may have resulted in this transient toxicity. Raised levels of serum cytokines including IL-6 in these patients implicate cytokine release as one of several potential factors exacerbating the observed respiratory toxicity. Whilst improved CAR designs and T cell production methods could improve the systemic persistence and activity, methods to control CAR T 'on-target, off-tissue' toxicity are required to enable a clinical impact of this approach in solid malignancies.


Assuntos
Antígeno Carcinoembrionário/imunologia , Imunoterapia Adotiva/métodos , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Dor Abdominal/etiologia , Adulto , Idoso , Anemia/etiologia , Antígeno Carcinoembrionário/genética , Antígeno Carcinoembrionário/metabolismo , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Imunoterapia Adotiva/efeitos adversos , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Pulmão/metabolismo , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/efeitos adversos , Agonistas Mieloablativos/agonistas , Neoplasias/genética , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Linfócitos T/transplante , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/efeitos adversos , Vidarabina/análogos & derivados , Vômito/etiologia
8.
Phys Chem Chem Phys ; 19(11): 7996-8007, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28263328

RESUMO

Recently, the search for and synthesis of unconventional stoichiometric compounds have become one of the most active areas of high pressure research. Here, we report the synthesis of two new stoichiometric compounds, namely KBr3 and KBr5, at high pressures in the K-Br system. Until now, KBr was the only known compound in this system. Two independent experimental techniques, namely Raman spectroscopy and X-ray diffraction measurements, were employed to detect and confirm the formation of the new compounds. A room temperature chemical reaction between KBr and Br2 resulted in the formation of orthorhombic KBr3 at ∼2.0 GPa. Further compression led to the formation of monoclinic KBr5 at ∼6.0 GPa. This was accompanied by an anomalously large pressure (>2 GPa) increase inside the sample chamber and it remained stable up to the highest pressure, 24 GPa, of our study. Upon decompression, KBr5 remained stable down to 5.0 GPa. High-pressure (14-20 GPa) and high-temperature (>1500 K) laser heating experiments showed the decomposition of KBr5 into KBr3 (trigonal) and Br2 with a large volume reduction. First-principles structural searches were carried out to solve the composition and related crystal structures. The proposed structures give good description of the experimental Raman spectra and X-ray diffraction data. The electronic structure calculations reveal semiconducting behaviour for these compounds.

9.
J Synchrotron Radiat ; 23(2): 629-34, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26917153

RESUMO

The protein crystallography beamline (PX-BL21), installed at the 1.5 T bending-magnet port at the Indian synchrotron (Indus-2), is now available to users. The beamline can be used for X-ray diffraction measurements on a single crystal of macromolecules such as proteins, nucleic acids and their complexes. PX-BL21 has a working energy range of 5-20 keV for accessing the absorption edges of heavy elements commonly used for phasing. A double-crystal monochromator [Si(111) and Si(220)] and a pair of rhodium-coated X-ray mirrors are used for beam monochromatization and manipulation, respectively. This beamline is equipped with a single-axis goniometer, Rayonix MX225 CCD detector, fluorescence detector, cryogenic sample cooler and automated sample changer. Additional user facilities include a workstation for on-site data processing and a biochemistry laboratory for sample preparation. In this article the beamline, other facilities and some recent scientific results are briefly described.


Assuntos
Cristalografia por Raios X/métodos , Proteínas/química , Síncrotrons
10.
Phys Chem Chem Phys ; 18(11): 8065-74, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26924455

RESUMO

Oxalic acid dihydrate, an important molecular solid in crystal chemistry, ecology and physiology, has been studied for nearly 100 years now. The most debated issues regarding its proton dynamics have arisen due to an unusually short hydrogen bond between the acid and water molecules. Using combined in situ spectroscopic studies and first-principles simulations at high pressures, we show that the structural modification associated with this hydrogen bond is much more significant than ever assumed. Initially, under pressure, proton migration takes place along this strong hydrogen bond at a very low pressure of 2 GPa. This results in the protonation of water with systematic formation of dianionic oxalate and hydronium ion motifs, thus reversing the hydrogen bond hierarchy in the high pressure phase II. The resulting hydrogen bond between a hydronium ion and a carboxylic group shows remarkable strengthening under pressure, even in the pure ionic phase III. The loss of cooperativity of hydrogen bonds leads to another phase transition at ∼ 9 GPa through reorientation of other hydrogen bonds. The high pressure phase IV is stabilized by a strong hydrogen bond between the dominant CO2 and H2O groups of oxalate and hydronium ions, respectively. These findings suggest that oxalate systems may provide useful insights into proton transfer reactions and assembly of simple molecules under extreme conditions.

11.
J Synchrotron Radiat ; 22(5): 1233-41, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26289275

RESUMO

XANES- and EXAFS-based analysis of the Ayurvedic Hg-based nano-drug Rasasindura has been performed to seek evidence of its non-toxicity. Rasasindura is determined to be composed of single-phase α-HgS nanoparticles (size ∼24 nm), free of Hg(0) or organic molecules; its structure is determined to be robust (<3% defects). The non-existence of Hg(0) implies the absence of Hg-based toxicity and establishes that chemical form, rather than content of heavy metals, is the correct parameter for evaluating the toxicity in these drugs. The stable α-HgS form (strong Hg-S covalent bond and robust particle character) ensures the integrity of the drug during delivery and prevention of its reduction to Hg(0) within the human body. Further, these comparative studies establish that structural parameters (size dispersion, coordination configuration) are better controlled in Rasasindura. This places the Ayurvedic synthesis method on par with contemporary techniques of nanoparticle synthesis.


Assuntos
Compostos de Mercúrio/análise , Compostos de Mercúrio/química , Mercúrio/análise , Espectroscopia por Absorção de Raios X/métodos , Disponibilidade Biológica , Cristalização , Composição de Medicamentos , Ayurveda , Compostos de Mercúrio/síntese química , Compostos de Mercúrio/toxicidade , Nanopartículas , Tamanho da Partícula , Pós , Solubilidade
12.
Phys Chem Chem Phys ; 17(48): 32204-10, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26577027

RESUMO

(p-Chloroanilinium)2CuCl4(C2H14Cl6CuN2) is from an important family of organic-inorganic layered hybrid compounds which can be a possible candidate for multiferroicity. In situ high pressure FTIR, Raman and resistivity measurements on this compound indicate the weakening of Jahn-Teller distortion and the consequent removal of puckering of the CuCl6(4-) octahedra within the layer. These effects trigger insulator to semiconductor phase transition along with a change in the sample colour from yellow to dark red. This article explains the crucial role of the anisotropic volume reduction of the CuCl6(4-) octahedron (caused due to the quenching of Jahn-Teller distortion) in the observed insulator to semiconductor phase transition.

13.
Indian J Med Res ; 141(1): 100-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25857501

RESUMO

BACKGROUND & OBJECTIVES: In the traditional system of medicine in India Ashwagandha powder and Sidh Makardhwaj have been used for the treatment of rheumatoid arthritis. However, safety and efficacy of this treatment have not been evaluated. Therefore, the present study was carried out to evaluate the efficacy and safety of Ayurvedic treatment (Ashwagandha powder and Sidh Makardhwaj) in patients with rheumatoid arthritis. METHODS: One hundred and twenty five patients with joint pain were screened at an Ayurvedic hospital in New Delhi, India. Eighty six patients satisfied inclusion criteria and were included in the study. Detailed medical history and physical examination were recorded. Patients took 5g of Ashwagandha powder twice a day for three weeks with lukewarm water or milk. Sidh Makardhwaj (100 mg) with honey was administered daily for the next four weeks. The follow up of patients was carried out every two weeks. The primary efficacy end point was based on American College of Rheumatology (ACR) 20 response. Secondary end points were ACR50, ACR70 responses, change from baseline in disease activity score (DAS) 28 score and ACR parameters. Safety assessments were hepatic function [alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), bilirubin and ß2 microglobulin], renal function (urea and creatinine and NGAL) tests and urine mercury level. RESULTS: The study was completed by 90.7 per cent (78/86) patients. Patients with moderate and high disease activity were 57.7 per cent (45/78) and 42.3 per cent (33/78), respectively. All patients were tested positive for rheumatoid factor and increased ESR level. Ashwagandha and Sidh Makardhwaj treatment decreased RA factor. A significant change in post-treatment scores of tender joint counts, swollen joint counts, physician global assessment score, patient global assessment score, pain assessment score, patient self assessed disability index score and ESR level were observed as compared to baseline scores. ACR20 response was observed in 56.4 per cent (44/78) patients (American College of Rheumatology criteria) and moderate response in 39.74 per cent (31/78) patients [European League Against Rheumatism (EULAR) criteria]. Ayurvedic treatment for seven weeks in rheumatoid arthritis patients showed normal kidney and liver function tests. However, increased urinary mercury levels were was observed after treatment. INTERPRETATION & CONCLUSIONS: The findings of the present study suggest that this Ayurvedic treatment (Ashwagandha powder and Sidh Makardhwaj) has a potential to be used for the treatment of rheumatoid arthritis. However, due to small sample size, short duration, non randomization and lack of a control group as study limitations, further studies need to be done to confirm these findings.


Assuntos
Artrite Reumatoide/terapia , Ayurveda , Segurança do Paciente , Extratos Vegetais , Feminino , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos
14.
J Synchrotron Radiat ; 21(Pt 6): 1296-304, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25343798

RESUMO

Short-range order has been investigated in Zr69.5Cu12Ni11Al7.5 and Zr41.5Ti41.5Ni17 metallic glasses using X-ray absorption spectroscopy and ab initio molecular dynamics simulations. While both of these alloys are good glass formers, there is a difference in their glass-forming abilities (Zr41.5Ti41.5Ni17 > Zr69.5Cu12Ni11Al7.5). This difference is explained by inciting the relative importance of strong chemical order, icosahedral content, cluster symmetry and configuration diversity.

15.
Indian J Med Res ; 139(4): 610-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24927349

RESUMO

BACKGROUND & OBJECTIVES: Sidh Makardhwaj (SM) is a mercury based Ayurvedic formulation used in rheumatoid arthritis and neurological disorders. However, toxicity concerns due to mercury content are often raised. Therefore, the present study was carried out to evaluate the effect of SM on brain cerebrum, liver and kidney in rats. METHODS: Graded doses of SM (10, 50, 100 mg/kg), mercuric chloride (1 mg/kg) and normal saline were administered orally to male Wistar rats for 28 days. Behavioural parameters were assessed on days 1, 7, 14 and 28 using Morris water maze, passive avoidance, elevated plus maze and rota rod. Liver and kidney function tests were done on day 28. Animals were sacrificed and brain cerebrum acetylcholinesterase activity, levels of malondialdehyde (MDA), reduced glutathione (GSH) in brain cerebrum, liver, kidney were estimated. The levels of mercury in brain cerebrum, liver and kidney were estimated and histopathology of these tissues was also performed. RESULTS: SM in the doses used did not cause significant change in neurobehavioural parameters, brain cerebrum AChE activity, liver (ALT, AST, ALP bilirubin) and kidney (serum urea and creatinine) function tests as compared to control. The levels of mercury in brain cerebrum, liver, and kidney were found to be raised in dose dependent manner. However, the levels of MDA and GSH in these tissues did not show significant changes at doses of 10 and 50 mg/kg. Also, there was no histopathological change in cytoarchitecture of brain cerebrum, liver, and kidney tissues at doses of 10 and 50 mg/kg. INTERPRETATION & CONCLUSIONS: The findings of the present study suggest that Sidh Makardhwaj upto five times the equivalent human dose administered for 28 days did not show any toxicological effects on rat brain cerebrum, liver and kidney.


Assuntos
Cérebro/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Ayurveda , Cloreto de Mercúrio/farmacocinética , Cloreto de Mercúrio/toxicidade , Acetilcolinesterase/metabolismo , Administração Oral , Análise de Variância , Animais , Glutationa/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Cloreto de Mercúrio/administração & dosagem , Ratos , Teste de Desempenho do Rota-Rod , Fatores de Tempo
16.
J Synchrotron Radiat ; 20(Pt 1): 137-44, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23254666

RESUMO

In this work nanoclusters formed in a Pt/Ni/C multi-trilayer by the ion-irradiated method of synthesis are characterized. In particular, an attempt to understand the role of interfaces in the synthesis is made. With this objective, ion-irradiation-induced structural changes in a Pt/Ni/C multi-trilayer using X-ray absorption spectroscopy (at the Ni K-edge) in conjunction with the X-ray standing-wave technique are investigated. The XANES analysis identifies chemical binding at pristine Ni/C and Ni/Pt interfaces, in contrast with physical adsorption at the Pt/C interface. The chemical nature of the interfaces determines their relative stability with respect to irradiation and controls the extent of metallic diffusion. The most interesting structural change, upon irradiation, is the disruption of the Pt/C interface and subsequent migration of Pt atoms towards pre-diffused Ni atoms within the C layer, leading to the formation of Ni-centered Ni-Pt bimetallic nanoclusters (with Ni:Pt = 60:40). These clusters are highly disordered beyond their nearest neighbor and find wide-scale applications as, for example, magnetic devices etc. The implications of these findings on the design goals are discussed.

17.
J Phys Chem A ; 117(28): 5734-41, 2013 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-23822139

RESUMO

The conformation of glycine has been a subject of extensive research for the past several years. As glycine exists in zwitterionic form in liquids and solids, the experimental observations of its neutral conformation are very limited. The complexes of glycine are simple prototypes to study the conformational properties of glycine. We have investigated the high-pressure behavior of glycine lithium sulfate (GLS), a semiorganic complex of glycine using X-ray diffraction, Raman spectroscopy, and density functional theory (DFT)-based first principles calculations. Our Raman studies and DFT calculations suggest formation of an intramolecular hydrogen bond at higher pressures. Subsequent to a structural transformation to a new high-pressure phase at ∼9 GPa, the observed spectral changes in the Raman spectra above 14 GPa indicate possible conformational change of glycine from zwitterionic to neutral form. At pressures above 18 GPa, the characteristic features in the Raman spectra and the X-ray diffraction patterns suggest transformation to a hydrogen-bond-assisted polymeric phase with intermediate range order.


Assuntos
Glicina/química , Lítio/química , Compostos Organometálicos/síntese química , Sulfatos/química , Glicina/análogos & derivados , Ligação de Hidrogênio , Conformação Molecular , Compostos Organometálicos/química , Polimerização , Pressão , Teoria Quântica , Análise Espectral Raman
18.
Lepr Rev ; 84(4): 316-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24745131

RESUMO

Amidst the plethora of ocular complications of leprosy, involvement of the posterior segment or optic nerve is extremely rare. The mechanism of optic neuritis in leprosy is poorly understood. A 47 year-old man presented with a single lesion suggestive of mid-borderline (BB) leprosy over left periorbital region; the histology showed borderline lepromatous (BL) leprosy with a BI of 3+. After initial improvement with WHO MDT-MB and prednisolone (40 mg/d) he developed sudden and painless diminished vision in the left eye, about 3 weeks later. His visual acuity was 6/9 in the left and 6/6 in the right eye, and there was left optic disc edema, hyperemia and blurred disc margins. Treatment with prednisolone (60 mg/d) along with WHO MDT-MB continued. A month later he returned with painless diminished vision in the other eye as well. Visual acuity was 6/6 in the right and 6/12 in the left eye, and there was right optic disc edema and left optic disc atrophy. CT of the head and MRI of the brain were normal. Inflammatory edema of the orbital connective tissue or other surrounding structures, or direct infiltration of vasa nervosa with resultant vascular occlusion leading to optic nerve ischemia, seems the most plausible explanation of optic nerve involvement in this case.


Assuntos
Hansenostáticos/uso terapêutico , Hanseníase Dimorfa/patologia , Nervo Óptico/patologia , Prednisolona/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Clofazimina/administração & dosagem , Dapsona/administração & dosagem , Quimioterapia Combinada , Humanos , Índia , Hanseníase Dimorfa/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Oftalmoscopia , Disco Óptico/patologia , Rifampina/administração & dosagem , Acuidade Visual , Testes de Campo Visual
19.
Sci Adv ; 9(8): eade5745, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36827368

RESUMO

Melting of solids is a fundamental natural phenomenon whose pressure dependence has been of interest for nearly a century. However, the temporal evolution of the molten phase under pressure has eluded measurements because of experimental challenges. By using the shock front as a fiducial, we investigated the time-dependent growth of the molten phase in shock-compressed germanium. In situ x-ray diffraction measurements at different times (1 to 6 nanoseconds) behind the shock front quantified the real-time growth of the liquid phase at several peak stresses. These results show that the characteristic time for melting in shock-compressed germanium decreases from ~7.2 nanoseconds at 35 gigapascals to less than 1 nanosecond at 42 gigapascals. Our melting kinetics results suggest the need to consider heterogeneous nucleation as a mechanism for shock-induced melting and provide an approach to measuring melting kinetics in shock-compressed solids.

20.
COPD ; 9(3): 305-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22568662

RESUMO

BACKGROUND: Left ventricular diastolic dysfunction (LVDD) is observed frequently in advanced COPD and it appears unrelated to the co-presence of its common risk factors as hypertension, diabetes, ischemic heart disease, etc. The patho-physiology of this association is yet unclear. We postulated that ischemia not apparent in the routine clinical evaluation could be the cause of such LVDD. METHOD: Advanced COPD (GOLD III & IV) patients being excluded of concomitant presence of hypertension, diabetes, ischemic heart disease, and hypothyroidism by conventional evaluations were looked for the presence of LVDD by tissue Doppler echocardiography. The subjects having LVDD were further evaluated with 99(m)Tc MIBI stress myocardial perfusion imaging to detect the presence of ischemia. RESULTS: 7 out of 14 patients of advanced COPD sufferers without any known risk factors for LVDD had reversible perfusion defect in the stress perfusion imaging predominantly involving the inferior wall myocardium (71.43%). Most of the defects, though significant, were not picked up by stress ECG. CONCLUSION: Reversible ischemic defects are quite common (50%) in advanced COPD patients with LVDD without the presence of common risk factors. This association needs further evaluation.


Assuntos
Isquemia Miocárdica/complicações , Doença Pulmonar Obstrutiva Crônica/complicações , Disfunção Ventricular Esquerda/complicações , Idoso , Diástole , Ecocardiografia Doppler , Eletrocardiografia , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagem
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