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1.
Cureus ; 15(10): e46448, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37927686

ABSTRACT

Adenocarcinoma of the gallbladder is the most common gallbladder carcinoma. But lymphoid stroma in gallbladder carcinoma is one of the rarest presentations. A unique case of gallbladder adenocarcinoma with lymphoid stroma in a 47-year-old female is presented in this report. The surgically resected gallbladder demonstrated invasive adenocarcinoma with lymphoid stroma, though it was radiologically diagnosed as xanthogranulomatous cholecystitis. Adenocarcinoma was immunohistochemically positive for pancytokeratin (AE1/AE3), cytokeratin 7 (CK7), cytokeratin 20 (CK20), and carcinoembryonic antigen (CEA). Lymphoid stroma was positive for CD45, where B-cell zones were CD20 and CD79a positive, and T-cell zones were CD3 positive, with a larger T-cell subset being positive for CD4 than CD8. This is the fourth reported case of gallbladder adenocarcinoma with lymphoid stroma, which needs to be studied for pathogenesis, prognosis, and future therapy, if any.

2.
Phys Rev E ; 106(2-1): 024701, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36109977

ABSTRACT

We formulate a comprehensive hydrodynamic theory of two-dimensional liquid crystals with generic p-fold rotational symmetry, also known as p-atics, of which nematics (p=2) and hexatics (p=6) are the two best known examples. Previous hydrodynamic theories of p-atics are characterized by continuous O(2) rotational symmetry, which is higher than the discrete rotational symmetry of p-atic phases. By contrast, here we demonstrate that the discrete rotational symmetry allows the inclusion of additional terms in the hydrodynamic equations, which, in turn, lead to novel phenomena, such as the possibility of flow alignment at high shear rates, even for p>2. Furthermore, we show that any finite imposed shear will induce long-ranged orientational order in any p-atic liquid crystal, in contrast to the quasi-long-ranged order that occurs in the absence of shear. The induced order parameter scales like a nonuniversal power of the applied shear rate at small shear rates.

3.
Phys Rev Lett ; 129(6): 067801, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-36018634

ABSTRACT

We formulate a hydrodynamic theory of p-atic liquid crystals, namely, two-dimensional anisotropic fluids endowed with generic p-fold rotational symmetry. Our approach, based on an order parameter tensor that directly embodies the discrete rotational symmetry of p-atic phases, allows us to unveil several unknown aspects of flowing p-atics, that previous theories, characterized by O(2) rotational symmetry, could not account for. This includes the onset of long-ranged orientational order in the presence of a simple shear flow of arbitrary shear rate, as opposed to the standard quasi-long-ranged order of two-dimensional liquid crystals, and the possibility of flow alignment at large shear rates.

5.
Endocr Pract ; 27(6): 601-606, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33645514

ABSTRACT

BACKGROUND: Tuberculosis of the adrenal glands may cause overt or subclinical adrenal insufficiency. An algorithm-based approach including assessment of paired basal cortisol and plasma adrenocorticotropic hormone (ACTH), short Synacthen, and plasma renin activity assays could be useful to diagnose all forms of adrenal insufficiency. METHODS: This cross-sectional study included consecutive, treatment-naive subjects diagnosed with pulmonary tuberculosis. Tuberculosis severity was classified by radiological criteria. Baseline parameters plus morning (8 am) serum cortisol and paired plasma ACTH were measured in all patients. Synacthen stimulation tests and plasma renin activity assays were performed as required. RESULTS: Eighty-four treatment-naive consecutive cases of pulmonary tuberculosis were evaluated for adrenal insufficiency. Twenty-seven (32.14%) subjects had normal adrenocortical function and 8 (9.5%), 7 (8.3%), 40 (47.6%), and 2 (2.4%) subjects had stage 1, stage 2, stage 3, and stage 4 adrenal insufficiency, respectively. Serum cortisol was negatively correlated with radiological severity (P = .01) and duration of illness (P = .001). Adrenal dysfunction was present in 27.3%, 82.5%, and 80% of those with radiologically minimal, moderately advanced, and far-advanced disease, respectively. Mean cortisol was 19.74 ± 5.52, 17.42 ± 8.53, and 15.71 ± 7.14 (µg/dL) in the 3 groups, respectively (P = .042). Hyponatremia was present in 83.3% of the patients. Serum sodium was negatively correlated with severity but not with the duration of disease. CONCLUSION: The prevalence of overt and subclinical adrenal dysfunction in pulmonary tuberculosis was high and was correlated with disease severity and duration. An algorithmic approach may be useful to detect the same and may have important clinical implications.


Subject(s)
Adrenal Insufficiency , Tuberculosis, Pulmonary , Adrenal Insufficiency/diagnosis , Adrenal Insufficiency/epidemiology , Adrenocorticotropic Hormone , Cosyntropin , Cross-Sectional Studies , Humans , Hydrocortisone , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/epidemiology
6.
Phys Rev Lett ; 127(26): 268004, 2021 Dec 24.
Article in English | MEDLINE | ID: mdl-35029464

ABSTRACT

We present the hydrodynamic theory of coherent collective motion ("flocking") at a solid-liquid interface, and many of its predictions for experiment. We find that such systems are stable, and have long-range orientational order, over a wide range of parameters. When stable, these systems exhibit "giant number fluctuations," which grow as the 3/4th power of the mean number. Stable systems also exhibit anomalous rapid diffusion of tagged particles suspended in the passive fluid along any directions in a plane parallel to the solid-liquid interface, whereas the diffusivity along the direction perpendicular to the plane is not anomalous. In the remaining parameter space, the system becomes unstable.

7.
Phys Rev E ; 104(6-1): 064611, 2021 Dec.
Article in English | MEDLINE | ID: mdl-35030890

ABSTRACT

We construct the hydrodynamic theory of coherent collective motion ("flocking") at a solid-liquid interface. The polar order parameter and concentration of a collection of "active" (self-propelled) particles at a planar interface between a passive, isotropic bulk fluid and a solid surface are dynamically coupled to the bulk fluid. We find that such systems are stable, and have long-range orientational order, over a wide range of parameters. When stable, these systems exhibit "giant number fluctuations," i.e., large fluctuations of the number of active particles in a fixed large area. Specifically, these number fluctuations grow as the 3/4th power of the mean number within the area. Stable systems also exhibit anomalously rapid diffusion of tagged particles suspended in the passive fluid along any directions in a plane parallel to the solid-liquid interface, whereas the diffusivity along the direction perpendicular to the plane is nonanomalous. In other parameter regimes, the system becomes unstable.

8.
J Stroke Cerebrovasc Dis ; 29(8): 104957, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32689603

ABSTRACT

INTRODUCTION: Clinical spectrum of Moyamoya angiopathy (MMA) differs across populations with different ethnicity. This study, the largest one done among Indian population was undertaken to assess clinico-radiological profile of MMA patients in eastern India. METHODS: A single centre cross-sectional study was undertaken among 76 MMA cases. Each patient was evaluated for epidemiological, clinical and radiological characteristics. SPSS 25 was used for statistical analysis. P < 0.05 was taken as statistically significant. RESULTS: 36 (47.4%) were children without gender preponderance. There were female predominance among adults (male:female = 1:2.33). Mean age at onset of first neurological symptoms for children was 4.2 ± 2.0years, followed by 34.9 ± 58.2months of latency with final diagnosis at the mean age of 7.4 ± 3.5years. For adults, mean age of onset of first neurological symptoms was 31.5 ± 12.3years, followed by 14.7 ± 41.7months time gap and diagnosed at the mean age of 33.5 ± 12.5years. There was a statistically significant difference between child and adult regarding the diagnostic latency (p = 0.035). Fixed motor weakness (FMW) was the predominant symptom across the whole disease course. Among children predominant first neurological symptom was fixed motor weakness (FMW) (52.8%), followed by seizures (22.2%). FMW was predominant (55%) first neurological complaint, followed by headache (22.5%) among adults. Seizure was more prevalent among children both as first (p = 0.002) and presenting symptom at the time of diagnosis (p = 0.048). Over the course of the disease seizure was more common among children (p = 0.001), while headache was more common among adults (p = 0.017). Recurrence of symptoms was more common among children (p = 0.059). Infarcts were more common among children (91.7%) than adults (72.5%), while hemorrhage was seen only among adults (25%) (p = 0.004). Isolated cerebral cortex was involved more commonly among children (59.4%) than adults (36.1%), while isolated subcortical involvement was seen only among adults (19.4%) (p = 0.016). Majority of the MMA cases were of Suzuki stage 4 (39.5%) and 5 (27.6%). Brain atrophy was associated with diagnostic latency (p = 0.009). CONCLUSION: Indian Moyamoya presents similar to disease presentation in Caucasian and Japanese patients. It is a frequently overlooked cause of stroke in young, often with various non-motor presentations, failure to recognize which leads to delay in diagnosis. Radiological burden disproportionate to number of acute vascular events, with subtle neurological manifestations like headache or seizure, often with cognitive decline, should raise suspicion of MMA.


Subject(s)
Moyamoya Disease/diagnosis , Nervous System/physiopathology , Neurologic Examination , Symptom Assessment , Adolescent , Adult , Age of Onset , Child , Child, Preschool , Cross-Sectional Studies , Delayed Diagnosis , Female , Humans , India/epidemiology , Infant , Male , Middle Aged , Moyamoya Disease/epidemiology , Moyamoya Disease/physiopathology , Nervous System/diagnostic imaging , Predictive Value of Tests , Prevalence , Prognosis , Risk Factors , Young Adult
9.
Phys Rev E ; 101(3-1): 032602, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32289917

ABSTRACT

Recent experimental studies have demonstrated that cellular motion can be directed by topographical gradients, such as those resulting from spatial variations in the features of a micropatterned substrate. This phenomenon, known as topotaxis, has been extensively studied for topographical gradients at the subcellular scale, but can also occur in the presence of a spatially varying density of cell-sized features. Such a large-scale topotaxis has recently been observed in highly motile cells that persistently crawl within an array of obstacles with smoothly varying lattice spacing. We introduce a toy model of large-scale topotaxis, based on active Brownian particles. Using numerical simulations and analytical arguments, we demonstrate that topographical gradients introduce a spatial modulation of the particles' persistence, leading to directed motion toward regions of higher persistence. Our results demonstrate that persistent motion alone is sufficient to drive large-scale topotaxis and could serve as a starting point for more detailed studies on self-propelled particles and cells.

10.
J Vector Borne Dis ; 57(4): 295-300, 2020.
Article in English | MEDLINE | ID: mdl-34856708

ABSTRACT

BACKGROUND & OBJECTIVES: Lymphatic filariasis (LF) is a neglected parasitic disease of tropics and subtropics including India. Although the disease mostly affects adults, there are evidences that LF infection is often acquired during childhood. This study assessed the filarial epidemiology as well as awareness about the disease among school children in the rural areas of Bankura district, West Bengal, India. METHODS: Night blood samples of 1193 school children were examined to detect microfilariae. They were examined clinically by a physician for filarial manifestations and inquired about their awareness on the disease. RESULTS: Microfilaria rate and disease rate among school children of the study area were assessed as 3.69% and 8.97% respectively. Only 12.74% of the school children had proper knowledge about filariasis and 72.09% had filarial patients living nearby. Among those affected children, 53.79% never received proper medical attention and 66.21% were found to be anxious about the fate of their filarial problems. School going males were found to be more affected than the females. Anxiety about the effect of the disease in girls was higher due to societal and medical ignorance among women that might develop psychological concerns. INTERPRETATION & CONCLUSION: This study suggests that, in the present study area, about 12.15% population acquired filarial infection at the stage of schooling. But effort for developing awareness about filariasis among the school children is scanty, which is presumably one of the major causes of high endemicity. To rectify the situation, knowledge about mosquito and mosquito borne diseases, including LF, should be properly incorporated in school curriculum. Control measures like anti-filarial drug administration and morbidity-management can be implemented in schools by the local governments, as it should be.


Subject(s)
Elephantiasis, Filarial , Animals , Child , Elephantiasis, Filarial/epidemiology , Female , Humans , India/epidemiology , Male , Microfilariae , Prevalence , Schools , Wuchereria bancrofti
11.
Proc Natl Acad Sci U S A ; 116(39): 19264-19273, 2019 09 24.
Article in English | MEDLINE | ID: mdl-31492815

ABSTRACT

We discuss the physical mechanisms that promote or suppress the nucleation of a fluid-filled lumen inside a cell assembly or a tissue. We discuss lumen formation in a continuum theory of tissue material properties in which the tissue is described as a 2-fluid system to account for its permeation by the interstitial fluid, and we include fluid pumping as well as active electric effects. Considering a spherical geometry and a polarized tissue, our work shows that fluid pumping and tissue flexoelectricity play a crucial role in lumen formation. We furthermore explore the large variety of long-time states that are accessible for the cell aggregate and its lumen. Our work reveals a role of the coupling of mechanical, electrical, and hydraulic phenomena in tissue lumen formation.


Subject(s)
Extracellular Fluid/metabolism , Extracellular Space/physiology , Models, Biological , Biophysical Phenomena , Electrophysiological Phenomena , Hydrodynamics , Permeability , Spheroids, Cellular/physiology
12.
Phys Rev Lett ; 122(21): 218002, 2019 May 31.
Article in English | MEDLINE | ID: mdl-31283334

ABSTRACT

We show that inversion-asymmetric tethered membranes exhibit a new double-spiral phase with long range orientational order not present in symmetric membranes. We calculate the universal algebraic spiral shapes of these membranes in this phase. Asymmetry can trigger the crumpling of these membranes as well. In vitro experiments on lipid membranes, red blood cell membrane extracts, and on graphene coated on one side, could test these predictions.

13.
Phys Rev E ; 99(5-1): 053004, 2019 May.
Article in English | MEDLINE | ID: mdl-31212455

ABSTRACT

We develop the elastic theory for inversion-asymmetric tethered membranes and use it to identify and study their possible phases. Asymmetry in a tethered membrane causes spontaneous curvature, which in general depends on the local in-plane dilation of the tethered network. This in turn leads to long-range interactions between the local mean and Gaussian curvatures, which are not present in symmetric tethered membranes. This interplay between asymmetry and Gaussian curvature leads to a double-spiral phase not found in symmetric tethered membranes. At temperature T=0, tethered membranes of arbitrarily large size are always rolled up tightly into a conjoined pair of Archimedes' spirals. At finite T this spiral structure swells up significantly into algebraic spirals characterized by universal exponents, which we calculate. These spirals have long-range orientational order, and are the asymmetric analogs of statistically flat symmetric tethered membranes. We also find that sufficiently strong asymmetry can trigger a structural instability leading to crumpling of these membranes as well. This provides a mechanism for crumpling of asymmetric tethered membranes which is not present for symmetric membranes. We calculate the maximum linear extent L_{c} beyond which the membrane crumples, and calculate the universal dependence of L_{c} on the membrane parameters. By tuning the asymmetry parameter, L_{c} can be continuously varied, implying a scale-dependent crumpling. Our theory can be tested in controlled experiments on lipids with artificial deposits of spectrin filaments, in in vitro experiments on red blood cell membrane extracts, and on graphene coated on one side.

14.
J Assoc Physicians India ; 67(2): 11-12, 2019 Feb.
Article in English | MEDLINE | ID: mdl-35042307

ABSTRACT

Goodpasture Syndrome with a rare incidence of one case per million accounts for 20% of RPGN cases. It occurs due to antibodies against the NC1 domain of the alpha3 chain of type IV collagen. It usually presents with glomerulonephritis & pulmonary hemorrhage. But 35% may present with glomerulonephritis alone. Circulating anti-GBM antibodies may not be present always. Herein we present a 24-year-old female from our IPGMER & SSKM Hospital, Kolkata with complaints of 30 days fever, 25 days of erythematous Skin lesions, 7 days of cola colored frothy urine, 3 days of anasarca & Oliguria, 3 days of shortness of breath & cough. Chest-X-ray revealed Pulmonary vascular congestion. Yet no history of pulmonary hemorrhage. ABG revealed Type 1 respiratory failure. ST-T changes in ECG & Dilated left Atrium and ventricle with severe Global Hypokinesia & EF 44% in Echocardiography. Very high Troponin-I (247.62). Plenty of Dysmorphic RBC & RBC Cast in Urine study. Urea 62 Creatinine 2.6 & 2.8gm protein per 24-hour urine. Evidence of Cardiomyopathy & RPGN prompted us to start Pulse methylprednisolone. Hemodialysis was also initiated, which improved dyspnea & anasarca. ANA dsDNA ANCA MPO PR3 antiGBM came negative repeatedly. Renal Biopsy revealed NECROTISING CRESCENTIC GLOMERULONEPHRITIS WITH LINEAR Ig-G Staining consistent with Goodpasture Syndrome. The patient underwent 9 rounds of Plasmapheresis and subsequently being followed up on monthly daycare basis cyclophosphamide immunosuppression (EUVASCYCLOPS protocol) and Oral Prednisolone regimen. ESRD was successfully averted. Erythematous Skin lesions Biopsy confirmed perforating dermatoses. Discussion: Possibly cardiomyopathy could have resulted from oliguria due to RPGN in this case Conclusion: To our knowledge, this is a unique and rare case of co-existence of DCM with anti-GBM negative Renal involvement only Goodpasture disease along with perforating dermatoses.

15.
Eur J Pharm Sci ; 109: 359-371, 2017 Nov 15.
Article in English | MEDLINE | ID: mdl-28821436

ABSTRACT

Herein, we demonstrate the preparation of highly luminescent carbon quantum dots (CQDs) from Aloe vera leaf gel; in just 2h at 250°C through carbonization pathway. The prepared CQDs are structurally characterized with high resolution transmission electron microscopy (HRTEM), hydrodynamic diameter, surface polarity, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Raman, UV-visible absorption spectrophotometry and fluorescence spectroscopy. The functional carbon nanoparticles are observed as non-cytotoxic materials. The biocompatibility, less cytotoxicity and high aqueous dispersibility of as-synthesized CQDs are motivated to design carbon quantum dot (CQD) tailored calcium alginate (CA) hydrogel films with an aim to controlled delivery of glycopeptides antibiotic vancomycin in the gastrointestinal tract (GI). With CQD, the drug loading capacity of CA/CQD film is increased to 89% from 38% (CA film), whereas; with ß-cyclodextrin (ß-CD) the vancomycin uptake capacity is increased more, 96%. The release of vancomycin through CA/CQD film is more pronounced at pH1.5, close to the pH of the stomach and it is found that in pH1.5 with ß-CD, the release rate of vancomycin is lowered, 56% in 120h. The high drug uptake capacity (96%) and lower release rate (56% in 120h) of CA/CQD hydrogel film in pH1.5 with ß-CD can be used for its applicability as drug delivery vehicle for controlled release of vancomycin into the stomach region and therefore it can offer a potential option for oral administration of vancomycin.


Subject(s)
Alginates/administration & dosage , Anti-Bacterial Agents/administration & dosage , Hydrogels/administration & dosage , Quantum Dots/administration & dosage , Vancomycin/administration & dosage , Alginates/chemistry , Aloe , Anti-Bacterial Agents/chemistry , Carbon/administration & dosage , Carbon/chemistry , Cell Survival/drug effects , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/chemistry , Drug Liberation , Glucuronic Acid/administration & dosage , Glucuronic Acid/chemistry , HeLa Cells , Hexuronic Acids/administration & dosage , Hexuronic Acids/chemistry , Humans , Hydrogels/chemistry , Hydrogen-Ion Concentration , Plant Leaves , Quantum Dots/chemistry , Vancomycin/chemistry
16.
Article in English | MEDLINE | ID: mdl-26651694

ABSTRACT

We construct a generic coarse-grained dynamics of a thin inflexible planar layer of polar-ordered suspension of active particles that is frictionally coupled to an embedding isotropic passive fluid medium with a friction coefficient Γ. Being controlled by Γ, our model provides a unified framework to describe the long-wavelength behavior of a variety of thin polar-ordered systems, ranging from wet to dry active matter and free-standing active films. Investigations of the linear instabilities around a chosen orientationally ordered uniform reference state reveal generic moving and static instabilities in the system that can depend sensitively on Γ. Based on our results, we discuss estimation of bounds on Γ in experimentally accessible systems.

17.
J Clin Diagn Res ; 9(11): OD09-10, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26674108

ABSTRACT

Cyanosis in a case of ASD (atrial septal defect) without pulmonary arterial hypertension is quite rare. A patient with ASD and pneumonia is described who had a central cyanosis resulting from the drainage of deoxygenated blood from the inferior vena cava directly into the left atrium through the atrial septal defect due to the presence of an over-developed malpositioned Eustachian valve directed to the left atrium. In conclusion, ASD can present with cyanosis due to an over-developed Eustachian valve.

18.
Article in English | MEDLINE | ID: mdl-26565171

ABSTRACT

We study the active to absorbing phase transition (AAPT) in a simple two-component model system for a species and its mutant. We uncover the nontrivial critical scaling behavior and weak dynamic scaling near the AAPT that shows the significance of mutation and highlights the connection of this model with the well-known directed percolation universality class. Our model should be a useful starting point to study how mutation may affect extinction or survival of a species.


Subject(s)
Models, Biological , Mutation , Diffusion , Evolution, Molecular
19.
Article in English | MEDLINE | ID: mdl-26764658

ABSTRACT

We study phase transitions and the nature of order in a class of classical generalized O(N) nonlinear σ models (NLS) constructed by minimally coupling pure NLS with additional degrees of freedom in the form of (i) Ising ferromagnetic spins, (ii) an advective Stokesian velocity, and (iii) multiplicative noises. In examples (i) and (ii), and also (iii) with the associated multiplicative noise being not sufficiently long-ranged, we show that the models may display a class of unusual phase transitions between stiff and soft phases, where the effective spin stiffness respectively diverges and vanishes in the long wavelength limit at two dimensions (2D), unlike in pure NLS. In the stiff phase, in the thermodynamic limit the variance of the transverse spin (or, the Goldstone mode) fluctuations are found to scale with the system size L in 2D as lnlnL with a model-dependent amplitude, which is markedly weaker than the well-known lnL dependence of the variance of the broken symmetry modes in models that display quasi-long-range order in 2D. Equivalently, for N=2 at 2D the equal-time spin-spin correlations decay in powers of inverse logarithm of the spatial separation with model-dependent exponents. These transitions are controlled by the model parameters those couple the O(N) spins with the additional variables. In the presence of long-range noises in example (iii), true long-range order may set in 2D, depending upon the specific details of the underlying dynamics. Our results should be useful in understanding phase transitions in equilibrium and nonequilibrium low-dimensional systems with continuous symmetries in general.

20.
Article in English | MEDLINE | ID: mdl-25215691

ABSTRACT

Generic inhomogeneous steady states in an asymmetric exclusion process on a ring with a pair of point bottlenecks are studied. We show that, due to an underlying universal feature, measurements of coarse-grained steady-state densities in this model resolve the bottleneck structures only partially. Unexpectedly, it displays localization-delocalization transitions and confinement of delocalized domain walls, controlled by the interplay between particle number conservation and bottleneck competition for moderate particle densities.


Subject(s)
Models, Theoretical , Computer Simulation , Monte Carlo Method
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