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1.
Small ; 18(46): e2204152, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36216741

RESUMEN

The polymerization of 1,4-benzenediboronic acid (BDBA) on mica to form a covalent organic framework (COF-1) reveals a dramatic increase in crystallinity when physically confined by exfoliated graphene. COF-1 domains formed under graphene confinement are highly geometric in shape and on the order of square micrometers in size, while outside of the exfoliated flakes, the COF-1 does not exhibit long-range mesoscale structural order, according to atomic force microscopy imaging. Micro-Fourier transform infrared spectroscopy confirms the presence of COF-1 both outside and underneath the exfoliated graphene flakes, and density functional theory calculations predict that higher mobility and self-assembly are not causes of this higher degree of crystallinity for the confined COF-1 domains. The most likely origin of the confined COF-1's substantial increase in crystallinity is from enhanced dynamic covalent crystallization due to the water confined beneath the graphene flake.

2.
Philos Trans A Math Phys Eng Sci ; 378(2184): 20200038, 2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33040659

RESUMEN

Crossed beam energy transfer, CBET, in high-intensity laser-plasma interaction is investigated for the case of optically smoothed laser beams. In the two approaches to laser-driven inertial confinement fusion experiments, the direct-drive and the indirect-drive, CBET is of great importance because it governs the coupling of laser energy to the plasma. We use the two-dimensional wave-coupling code Harmony to simulate the transfer between two laser beams with speckle structure that overlap in a plasma with an inhomogeneous flow profile. We compare the CBET dynamics for laser beams with spatial incoherence and with spatio-temporal incoherence; in particular we apply the smoothing techniques using random phase plates (RPPs) and smoothing by spectral dispersion (SSD), respectively. It is found that for laser beams (wavelength λ0) with intensities (IL) above IL ∼ 2 × 1015 W cm-2(λ0/0.35 µm)-2(Te/keV), both the so-called plasma-induced smoothing as well as self-focusing in intense laser speckles induce temporal incoherence; the latter affects the CBET and the angular distribution of the light transmitted behind the zone of beam overlap. For RPP-smoothed incident beams, the resulting band width of the transmitted light can already be of the same order as the effective band width of the SSD available at major laser facilities. We examine the conditions when spatio-temporal smoothing techniques become efficient for CBET. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 1)'.

3.
J Indian Prosthodont Soc ; 14(Suppl 1): 210-4, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26199518

RESUMEN

Deterioration or malfunction of any part should be viewed as an effect that has the direct or indirect result of one or more identifiable cause. The establishment of definitive goals is the foundation for the full mouth rehabilitation. Severe wear is common in prosthodontic patients whose teeth have been held in functional interference for long period of time. This case report presents a description of a patient's oral rehabilitation with metal ceramic restorations to increase vertical dimension while achieving canine guided occlusion.

4.
Radiol Case Rep ; 19(2): 594-599, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38111551

RESUMEN

Liver abscess is a common disease, however, it is a rare cause of venous thrombosis. The incidence of amoebic and pyogenic liver abscess in developing countries is high, however, the occurrence of inferior vena cava thrombosis secondary to liver abscess is a very rare and life-threatening complication. Computed tomography (CT) scan is an ideal investigation tool for diagnosing the various complications associated with liver abscess. Here we describe 3 cases of liver abscess in patients who developed a rare vascular complication of inferior vena cava. Liver abscesses should be considered as a rare cause of IVC thrombosis in the correct clinical context. All the patients were managed with ultrasound-guided pigtail insertion and antimicrobial agents.

5.
Radiol Case Rep ; 19(6): 2467-2471, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38585398

RESUMEN

Visceral larva migrans (VLM) occurs due to migration of the second stage of larvae of nematodes through human viscera. It is an underdiagnosed entity which commonly affects the liver as eosinophilic abscesses and appears as coalescing, conglomerated cavities on imaging. This case report details the sonographic and CT features of an 8 year old female patient with right upper quadrant pain and peripheral eosinophilia on laboratory reports, diagnosed as a case of VLM on biopsy. Imaging of VLM shows overlap with neoplastic lesions and other infective pathologies hence this case aims to highlight the clinical, laboratory, and radiological features to help narrow the differential diagnosis.

6.
Radiol Case Rep ; 19(10): 4440-4444, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39185437

RESUMEN

Non-Hodgkin's lymphoma are neoplasms derived from T cells and B cells and their precursors in the lymphoid system with higher susceptibility in involvement of extra-nodal sites. Predominant ureteric involvement is an unusual presentation. We present a case of diffuse large B-cell lymphoma with secondary involvement of ureter who had symptoms of urinary tract infection in absence of positive urine culture, non-responsive to broad spectrum antibiotics and masquerading pyogenic infection leading to pyelonephritis with ureteritis. Radiological examination revealed mass like soft tissue thickening of ureter extending from renal pelvis throughout the length of ureter. FNAC as well as biopsy from the periureteric thickening revealed lymphomatous involvement of ureter. The following case report provides insight on differentials and varied symptoms of lymphomatous involvement of ureter.

7.
Radiol Case Rep ; 18(8): 2735-2737, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37304313

RESUMEN

Acardiac twin is a rare complication of monochorionic twin pregnancy. We present case of a 24 years-old primigravida with monochorionic pregnancy having an amorphous acardiac twin diagnosed during routine first trimester ultrasound scan. She was managed expectantly since there were no signs of hemodynamic compromise in the normal twin with close ultrasound fetal surveillance using gray scale and color Doppler ultrasound. Spontaneous regression of vascularity with reduced size of the acardiac twin was seen subsequently.

8.
Radiol Case Rep ; 18(4): 1601-1604, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36852291

RESUMEN

Polyarteritis nodosa is a necrotizing arteritis involving small and medium vessels. Polyarteritis nodosa can have variable presentations depending upon the organ involved. It can either present as a diffuse disease or a limited form confined to a particular organ. Isolated muscular involvement in this disease is rare, which may present as myalgia, nonspecific fever, weight loss or even as claudication. The imaging pattern on ultrasound and MRI can help diagnose this condition in the background of clinical history and muscle biopsy is confirmatory. We present a case of 15 years old boy who presented with fever, weight loss, myalgia in leg region. MRI and ultrasound examination showed perivascular inflammation in calf muscles with a characteristic "cotton wool" pattern of enhancement on contrast study.

9.
Radiol Case Rep ; 18(4): 1613-1616, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36865622

RESUMEN

Macrodystrophia lipomatosa is a rare form of nonhereditary congenital localized gigantism involving upper and lower limbs and is characterized by overgrowth of all the mesenchymal elements predominantly fibro-adipose component, in the distribution of a particular nerve, usually median nerve. It usually presents with progressive painless overgrowth of the involved limb, toe, or digit and is associated with macrodactyly. It might cause limitation of the movement of the involved part. Imaging has an important role in diagnosing this condition and differentiating it from malignant mimics. Imaging findings include hypertrophy of the mesenchymal elements of the involved digits and/or limbs predominantly fibro adipose component with associated overgrowth of the phalanges. In this case report, we present a case of unilateral involvement of index finger and thumb with associated macrodactyly.

10.
Radiol Case Rep ; 18(9): 3295-3298, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37497464

RESUMEN

Swyer syndrome-a rare syndrome associated with complete gonadal dysgenesis-is seen in phenotypically female patients with 46-XY karyotype. They usually present with primary amenorrhea or delayed puberty. The dysgenetic gonad, which is nonfunctional, is prone to undergo malignant transformation such as dysgerminoma, gonadoblastoma, etc. Timely diagnosis helps in deciding appropriate management strategies for the patient such as hormone replacement therapy and gonadectomy. Thirty-year-old patient with a female external phenotype presented to us with complaints of primary amenorrhea. There was no similar family history of infertility, amenorrhea, abnormal external genitalia development, or cryptorchidism. On physical examination, the breast development of the patient was within normal limits for her age (Tanner stage 5), however; the axillary and pubic hair were underdeveloped (Tanner stage 2). Pelvic and inguinal ultrasound of the patient showed a hypoplastic uterus along with a cystic structure in left pelvis with no evidence of any testes like structure in inguinal region, pelvis, or abdomen. The patient was further evaluated with MRI of pelvis which confirmed the ultrasound findings of a hypoplastic uterus along with a dysplastic cystic left gonad with no evidence of any ovary or ovary-like structure/testes/testes-like structure in abdomen. Possibility of complete gonadal dysgenesis was given which was further confirmed by the hormonal assay that showed hypergonadotropic-hypogonadism with raised serum follicular stimulating hormone (FSH) and serum luteinizing hormone (LH) levels and a low estradiol, low testosterone, and low anti-Mullerian hormone (AMH) levels. Serum prolactin (PRL), serum thyroid stimulating hormone (TSH), and serum beta human chorionic gonadotropin (beta hCG) levels were within normal range. The cytogenetic report of the patient showed a 46-XY karyotype confirming our diagnosis. The patient was advised to undergo prophylactic gonadectomy for the left gonad. Swyer syndrome is a rare disorder of sexual development which needs vigorous clinical, laboratory, and radiological evaluation. Ultrasound is the primary investigation of choice whereas MRI is used as a problem-solving tool in localizing the streak gonads. Early diagnosis is crucial in these patients since prophylactic gonadectomy reduces the risk of developing germ cell tumor.

11.
Radiol Case Rep ; 18(10): 3739-3747, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37609067

RESUMEN

Epithelioid hemangioendothelioma (EHE) of the liver is an extremely rare malignant tumor of vascular origin, representing less than 1 % of all vascular tumors. Nearly 260 cases have been reported in English literature. Radiologically it is seen as multifocal lesions. It can be seen at different sites like lungs, bones, lymph nodes, breasts, and soft tissue. Often it is misdiagnosed with metastases, cholangiocarcinoma, or angiosarcoma. No definite treatment protocol is available due to its rarity, however, these malignancies are treated by radical resection of the tumor or liver transplant and/or chemotherapy. Here we present a primary hepatic epithelioid hemangioendothelioma (HEHE) which was mimicking metastases in a 42-year-old male who was treated with chemotherapy and radiotherapy. Sadly the patient expired after 1 year of complete course of treatment. Imaging features can help to improve the diagnostic accuracy of this tumor.

12.
BMJ Case Rep ; 16(11)2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37977845

RESUMEN

Anorectal melanoma (ARM) is an exceedingly rare and very aggressive malignancy. It originates from the melanocytic cells in the anorectal mucosa, which produces melanin. Other mucosal melanomas commonly found in the mucosa of the oral cavity, vulvovaginal, pharynx and urinary tract. Patients usually present with bleeding per rectum, perianal pain and difficulty in defaecation. Distinction of primary anorectal melanoma from other tumours of this region is difficult because of the lack of common imaging features. MRI is the modality of choice for its better tissue characterisation and resolution. There is no standard treatment protocol available mainly due to scarcity of data. Surgery is the mainstay therapy. Herein we present a case of a male patient in his 30s who presented with rectal bleeding and perianal pain. Haematological analysis revealed normocytic normochromic anaemia. MRI detected a mass lesion in the anorectal region. Contrast enhanced CT revealed multiple metastases in the liver, lungs, periportal, mesorectal and inguinal lymph nodes. The diagnosis of the ulcerated anorectal melanoma was established on histopathological examination. The patient underwent abdominoperineal resection (APR) followed by chemotherapy. Afterward the patient presented to the emergency room with respiratory distress for which he was on ventilator support. Sadly, the patient died after four days.


Asunto(s)
Melanoma Amelanótico , Neoplasias del Recto , Neoplasias Cutáneas , Humanos , Masculino , Melanoma Amelanótico/diagnóstico , Melanoma Amelanótico/cirugía , Melanoma Amelanótico/patología , Neoplasias del Recto/patología , Neoplasias Cutáneas/patología , Hígado/patología , Hemorragia Gastrointestinal , Pulmón/patología , Dolor , Melanoma Cutáneo Maligno
13.
Radiol Case Rep ; 18(6): 2212-2218, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37123038

RESUMEN

Primary monophasic synovial sarcoma of the lung is an extremely rare malignant mesenchymal tumor that can develop at any anatomic site. Synovial sarcoma is considered a high grade tumor with a poor prognosis. Metastatic pulmonary sarcoma is much more common. Hence primary lesion elsewhere in the body needs exclusion. No clinical or radiological features are specific for pulmonary sarcoma, often it is confused with bronchogenic carcinoma. Therefore biopsy is needed to establish the diagnosis of this rare tumor. We hereby present two cases of histologically proven primary monophasic synovial sarcoma of lung. The imaging features of this rare disease is reviewed.

14.
Radiol Case Rep ; 18(5): 2024-2029, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37033687

RESUMEN

Primary squamous cell carcinoma of pancreas is a rare malignant neoplasm. It has been reported as case reports only, hence clinical information is limited. Here, we present a case of primary squamous cell carcinoma of pancreas in a 47-year-old female with a background history of chronic pancreatitis. Patient was treated with systemic chemotherapy; however, she did not respond to the treatment protocol. Follow-up CT scan showed increase in the size and extension of the lesion. It is an aggressive tumor and does not respond well to chemotherapy or radiotherapy.

15.
J Oral Biol Craniofac Res ; 12(5): 694-701, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36092459

RESUMEN

Objective: To determine the impact of the buccal envelope flap and pedicle design on the post-operative outcome and quality of life following lower third molar surgery (QoL). Materials and methods: A randomized case-control clinical study was carried out from September 2017 to September 2019. In this study, a total number of 50 patients with mandibular third molar impaction underwent surgical removal of the same using buccal envelope flap (group A) and pedicle flap (group B). The patients were assessed postoperatively for pain, swelling, trismus, wound dehiscence, dry socket, and quality of life for one month. Results: In terms of pain, swelling, and trismus, there was no statistical difference between the two groups (p > 0.05). However, there was a statistically significant difference found in group B (pedicle flap) in terms of wound dehiscence, dry socket, and quality of life (p < 0.05). Conclusion: The pedicle flap demonstrates fewer incidences of wound dehiscence, dry socket, and a better quality of life when compared to the envelope flap.

16.
J Mech Behav Biomed Mater ; 136: 105495, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36208582

RESUMEN

The influence of thermocycling on the surface deterioration of glazed monolithic high translucent 3Y-TZP dental restorations is still unclear. The purpose of this study therefore was to evaluate low temperature degradation (LTD), elemental release and surface degradation pattern after five years of simulated clinical time. A total of 123 specimens were prepared from second-generation high translucent 3Y-TZP as per ISO 6872:2015 standards (3 mm × 4 mm × 30 mm). They were classified as per glazing and thermocycling protocol; group CPT, DGT and IGT. Glaze materials were applied on one surface of the specimen and subjected to a thermocycling in artificial saliva, four-point bending test, inductively coupled plasma mass spectrometry (ICP-MS), scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDX) and x-ray diffraction (XRD). Flexural strength, characteristic strength and Weibull modulus values were derived from four-point bending test. Descriptive fractographic analysis of surfaces was conducted to observe the surface degradation characteristics and point of failure. Control/no glaze with thermocycling (CPT = 621.5, 1σ = 117.0 MPa) presented higher flexural strength values compared to glaze I with thermocycling (442.4, 1σ = 45.4 MPa) and glaze II with thermocycling (534.3, 1σ = 46.3 MPa). Characteristic strength from Weibull analysis also observed higher values (669.2 MPa) for the control specimens. XRD analysis showed that monoclinic volume fraction (Vm = 11.0, 1σ = 0.7%) was highest in control specimens. Fractographic analysis suggested that there was no correlation between the point of failure initiation and mean flexural strength values. Glazing protected the high translucent 3Y-TZP surface against LTD during thermocycling but negatively impacted on the flexural strength.


Asunto(s)
Resistencia Flexional , Circonio , Ensayo de Materiales , Temperatura , Circonio/química , Frío , Propiedades de Superficie , Materiales Dentales , Itrio/química , Cerámica/química
17.
Radiol Case Rep ; 16(7): 1732-1735, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34007393

RESUMEN

Anterior neck masses are common and such patients commonly present to ultrasonography units for further evaluation of underlying pathology. We encountered an atypical case of pulsatile anterior neck swelling in a 45-year-old lady. Evaluation of the swelling using neck ultrasonography and color doppler study revealed that the mass was of vascular origin and contrast-enhanced computed tomography of neck confirmed the presence of an aberrant high riding innominate artery. Knowledge of such variants is of great importance and should be reported by the concerned radiologist. Lack of knowledge of such variants may lead to inadvertent surgical complications during procedures and can be life-threatening to the patient.

18.
Materials (Basel) ; 14(22)2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34832419

RESUMEN

(1) Background: The effect of glazing on the mechanical properties of monolithic high translucent zirconia is not well reported. Therefore, the purpose of this study was to evaluate the effect of glazing on the flexural strength of high translucent zirconia; (2) Methods: Ninety specimens were prepared from second-generation 3Y-TZP high translucent blocks and divided into three groups. Glaze materials were applied on one surface of the specimen and subjected to a four-point bending test and flexural stress and flexural displacement values were derived. Descriptive fractographic analysis of surfaces was conducted to observe the point of failure and fracture pattern.; (3) Results: Control-nonglazed (647.17, 1σ = 74.71 MPa) presented higher flexural strength values compared to glaze I (541.20, 1σ = 82.91 MPa) and glaze II (581.10, 1σ = 59.41 MPa). Characteristic strength (σƟ) from Weibull analysis also observed higher (660.67 MPa) values for the control specimens. Confocal microscopy revealed that glazed surfaces were much rougher than control surfaces. Descriptive fractographic analysis revealed that there was no correlation between the point of failure initiation and flexural strength; (4) Conclusions: The test results demonstrated that glazing significantly decreased the flexural strength and flexural displacement of the zirconia specimens.

19.
Saudi J Kidney Dis Transpl ; 31(1): 136-143, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32129206

RESUMEN

Coronary artery calcification is an acceptable tool for cardiovascular risk assessment in end-stage renal disease (ESRD) population. We aimed to identify the association and predictive value of components of blood cell parameters with coronary and thoracic aorta vascular calcification (VC) in ESRD population on dialysis. All ESRD patients receiving hemodialysis or peritoneal dialysis aged between 18 and 60 years were included in the study. Exclusion criteria comprised patients with active infection or inflammatory disease, autoimmune disease, congestive heart failure, angina pectoris and/or documented coronary artery disease, thyroid disease, and hepatic dysfunction. Agatston scoring was used for the evaluation of coronary aorta calcification (CAC) score (CACS) and thoracic aorta calcification (TAC) score (TACS). Compared to participants with no VC, those who had VC were statistically significantly older (P <0.001) and had higher neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) (P = 0.02 and <0.001, respectively). On multivariate logistic regression analysis, increasing age (P = 0.00) and higher PLR (P = 0.04) were associated with an increased likelihood of exhibiting VC (CAC or TAC). There was a positive correlation between CACS and age (rs = 0.495, P = 0.00). A statistically significant positive correlation existed between TACS and age (rs = 0.516, P = 0.00). Similarly, a positive correlation was found between NLR, PLR, and TACS (rs = 0.334, P = 0.001, and rs = 0.438, P = 0.00, respectively). On multivariate linear regression analysis, increased age and red cell distribution width were found to be significant predictors of log(n) TACS. PLR of 135 gave a sensitivity of 80% and a specificity of 50% for predicting VC. Being a cost-effective and easily available investigation, the utilization of the correlation of NLR and PLR with CAC and TAC appears promising, particularly in the age group of 30-60 years.


Asunto(s)
Recuento de Células Sanguíneas/estadística & datos numéricos , Fallo Renal Crónico , Diálisis Renal , Calcificación Vascular , Adolescente , Adulto , Aorta Torácica/patología , Estudios Transversales , Femenino , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/epidemiología , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Medición de Riesgo , Calcificación Vascular/diagnóstico , Calcificación Vascular/epidemiología , Calcificación Vascular/etiología , Adulto Joven
20.
Indian J Cancer ; 59(1): 136-139, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35645057

Asunto(s)
Mama , Mamografía , Humanos
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