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Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome with a variable presentation. We present a case of a 55-year-old female who presented with pain in the bilateral hip region for the last two years. On routine biochemical evaluation, she was found to have hypophosphatemia with an X-ray of the bilateral hip region showing an acute stress fracture in the bilateral intertrochanteric region of the femur. An evaluation for the cause of hypophosphatemia revealed renal phosphate loss with low percentage tubular reabsorption of phosphate (% TRP) of 83% (reference range: 85-95%), with tubular maximum phosphate reabsorption per unit glomerular filtration rate (TmP/GFR) of 2.07 mg/dL (reference range: 2.5-4.5 mg/dL (0.67 mmol/L; range: 0.84-1.23 mmol/L)). Further evaluation revealed elevated levels of intact fibroblast growth factor, 445.7 pg/mL (reference range: 23-95 pg/mL). A 68-Gallium DOTA-1-Nal3-octreotide (DOTANOC) PET-CT revealed a focal increased tracer uptake with a lytic lesion at the lateral metaphyseal aspect of the proximal right tibia, suspicious of somatostatin receptor avid mesenchymal tumor, leading to the diagnosis of TIO. Definitive treatment with complete surgical excision of the tumor was done. Postoperatively, her phosphorus level was within the normal target range even without oral phosphate supplementation. While it is a rare condition, a proper and systemic workup can lead to timely diagnosis and management of this debilitating benign condition.
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Adrenocortical tumours are rare in children and account for only 0.3%-0.4% of all neoplasms in childhood. They present with variable signs and symptoms, depending on the type of hormonal hypersecretion. The majority of the adrenocortical tumours in children are functional (90%) and malignant (88%). Here, we describe a functional plurihormonal oncocytic adrenal cortical adenoma in a young girl, that mimicked a malignant adrenal lesion, clinically as well as on imaging and biochemical features. This report bears the objective of being aware of the atypical biochemical as well as imaging characteristics of oncocytic adrenal tumours.
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Neoplasias de la Corteza Suprarrenal , Adenoma Corticosuprarrenal , Femenino , Humanos , Adenoma Oxifílico/patología , Adenoma Oxifílico/diagnóstico , Adenoma Oxifílico/diagnóstico por imagen , Adenoma Oxifílico/cirugía , Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/cirugía , Neoplasias de la Corteza Suprarrenal/diagnóstico por imagen , Neoplasias de la Corteza Suprarrenal/patología , Adenoma Corticosuprarrenal/diagnóstico , Adenoma Corticosuprarrenal/cirugía , Adenoma Corticosuprarrenal/diagnóstico por imagen , Adenoma Corticosuprarrenal/patología , Diagnóstico Diferencial , Tomografía Computarizada por Rayos X , AdolescenteAsunto(s)
Fracturas Espontáneas , Hiperparatiroidismo Primario , Cálculos Renales , Osteítis Fibrosa Quística , Osteítis , Humanos , Osteítis Fibrosa Quística/diagnóstico por imagen , Osteítis Fibrosa Quística/etiología , Hiperparatiroidismo Primario/complicaciones , Hiperparatiroidismo Primario/diagnóstico por imagen , Cálculos Renales/complicaciones , Cálculos Renales/diagnóstico por imagen , RiñónRESUMEN
We have performed a combined quantum mechanical and microkinetic modeling study to understand the nascent decomposition pathways of methane pyrolysis, catalyzed by gas-phase ZnCl2, in a constant pressure batch reactor at 1273 K. We find that ZnCl2 catalyzes methane pyrolysis with an apparent activation energy of 227 kJ/mol. We have also performed sensitivity analysis on a reaction network comprising initiation, termination, and primary propagation reactions. The results suggest that the whole reaction network can be simplified to four reactions, which contributes to the initial rate of methane decomposition. Based on these insights, we have also explored the catalyzing effects of gas-phase AlCl3, CoCl2, CuCl2, FeCl2, and NiCl2 for methane decomposition. Our calculations suggest that gas-phase CuCl2 and NiCl2 are the most active catalysts among the metal halides studied in this work.
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Reduced molybdenum oxides are versatile catalysts for deoxygenation and hydrodeoxygenation reactions. In this work, we have performed spin-polarized DFT calculations to investigate oxygen healing energies on reduced molybdenum oxides (reduced α-MoO3 , γ-Mo4 O11 and MoO2 ). We find that Mo+4 on MoO2 (100) is the most active for abstracting an oxygen from the oxygenated compounds. We further explored CO2 adsorption and dissociation on reduced α-MoO3 (010) and MoO2 (100). In comparison to reduced α-MoO3 (010), CO2 adsorbs more strongly on MoO2 (100). We find that CO2 dissociates on MoO2 (100) via a two-step process, the overall barrier for which is 0.6â eV. This barrier is 1.7â eV lower than that on reduced α-MoO3 (010), suggesting a much higher activity for deoxygenation of CO2 to CO. As H2 dissociation is shown to be the rate-limiting step for hydrodeoxygenation reactions, we also studied activation barriers for H2 chemisorption on MoO2 (100). We find that the chemisorption barriers are 0.7â eV lower than that reported on reduced α-MoO3 (010). Finally, we have studied the dissociation (C-O cleavage) of anisole (a lignin-based biofuel model compound) on MoO2 (100). We find that anisole binds very strongly on MoO2 (100) with an adsorption energy of -1.47â eV. According to Sabatier's principle, strongly adsorbing reactants poison the catalyst surface, which may explain the low activity of MoO2 observed during experiments for hydrodeoxygenation of anisole.
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Molibdeno , Óxidos , Molibdeno/química , Óxidos/química , Oxígeno/química , Teoría Funcional de la Densidad , Dióxido de Carbono , AnisolesRESUMEN
An efficient protocol for the synthesis of tricyclic pyrrolidinochromenes has been developed via an intramolecular 1,3-dipolar cycloaddition of azomethine ylides generated in situ from 1,3-dienyl ester tethered O-hydroxyarylaldehyde and glycine esters. The reaction is highly regio- and diastereoselective in nature and provided the potentially bioactive pyrrolidine fused tricyclic cycloadducts in excellent yields with wide substrate scope. Interestingly this reaction constructs two rings and four contiguous stereogenic centers in which one of them is an all carbon quaternary center in a unique fashion.
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An unprecedented orthogonal cross-coupling between aromatic C(sp2) and aliphatic olefinic C(sp2) carbons of two same molecules via dual C-H bond activation in an intermolecular fashion has been developed using a distal ester-directing group. This new coupling reaction led to the synthesis of the highly functionalized 1,3-diaryl molecular architecture in very good yields and with high chemo- and regioselectivities. In addition, using ester as the distal directing group, ortho C-H olefination of α-methyl aryl acrylates and cinnamic esters with various alkenes has been achieved in very good yields and with a wide range of substrate scope.
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Chemoselective domino ring opening and selective O/S-alkylation of ethers/thioethers over enol C/O alkylation has been observed. Various 2-aryl chromanones/thiochromanones with alkyl/allyl bromides were smoothly converted into the corresponding highly functionalized ethers and thioethers in excellent yields with high selectivity. An unusual, chemoselective domino ring opening and selective ether/thioether O/S-alkylation over. An unusual, chemoselective domino ring opening and selective ether/thioether O/S alkylation over enol C/O alkylation has been observed.
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Éteres CíclicosRESUMEN
This paper describes a new synthetic strategy for the construction of tricyclic chromeno/quinolino furan frameworks via creation of two new rings and three contiguous stereogenic centers with high diastereoselectivity through a rhodium-catalyzed intramolecular carbonyl ylide cycloaddition reaction for the first time. This protocol allows the synthesis of the core ring system of natural products such as cordigol and lophirone H.
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A novel coronavirus (severe acute respiratory syndrome corononavirus-2; SARS-CoV-2) has affected millions of people across the world. The coronavirus disease (COVID-19) resulting from SARS-CoV-2 manifests in variable clinical severity, featuring both respiratory and extra-respiratory symptoms. Dermatological manifestations of COVID-19 are sparsely reported. To study the various dermatological findings in SARS-CoV-2 positive patients in Indian population. Institutional ethical committee permission was sought and102 SARS-CoV-2 positive patients were included in the study. A thorough clinical examination was done to determine the nature and frequency of various dermatological manifestations in these patients. Out of the 102 positive cases, 95 were males. The mean age of the group was 39.30 years. Thirteen patients (12.7%) were found to have dermatological manifestations. Three (2.9%) had maculopapular rash, two (1.9%) had urticarial lesions and eight (7.8%) patients had itching without any specific cutaneous signs. Trunk was the most frequently affected area, followed by the extremities. No mucosal signs and symptoms were detected. Dermatological manifestations were seen in a small group of COVID-19 patients. The presentation may vary in different population groups and based on severity of disease.
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COVID-19/complicaciones , Enfermedades Cutáneas Virales/fisiopatología , Adolescente , Adulto , Anciano de 80 o más Años , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la Enfermedad , Enfermedades Cutáneas Virales/epidemiología , Enfermedades Cutáneas Virales/virología , Adulto JovenRESUMEN
We have performed exact classical rate calculations to compute adsorption and desorption rate constants with a model representative of a real system. We compute the desorption rate using transition-state theory by taking the dividing-surface far from the surface of the solid. We find that using a mean-field assumption, i.e., applying potential of mean force to transition state theory, could lead to two orders-of-magnitude errors in the rate constant owing to large fluctuations in the desorption barrier. Furthermore, we compute the adsorption rate by including a dynamical factor which reflects the probability of sticking to the solid surface. We find that the sticking probability is highly sensitive to the coverage. Also, we find that the adsorption rate computed from the mean-field assumption is not very different from the exact adsorption rate. We also compute entropic contribution to desorption rates and compare it to that obtained from two limiting models of adsorption-2D ideal gas and 2D ideal lattice gas. We show that at high temperatures (700 K), the entropic contribution to desorption rates computed from the exact calculations is very close to that obtained from the 2D ideal gas model. However, for lower to intermediate temperatures from 200 K to 500 K, the entropic contributions cover a wide range which lies in between the two limiting models and could lead to over two-orders-of-magnitude errors in the rate coefficient.
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An efficient protocol for the introduction of acetoxy and hydroxy functionalities on unactivated aryl sp2 carbons of oxobenzoxazine derivatives via an ortho-C-H activation reaction using a palladium catalyst has been developed for the first time. Interestingly, this intermolecular C-H functionalization reaction takes place in a facile and simple manner with high chemo- and site selectivity.
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Avulsion of the optic nerve head is a rare and severe complication of ocular blunt trauma. Herein, we describe a case of 16-year-old boy, who presented with a rare combination of optic nerve avulsion associated with central retinal artery occlusion, following blunt trauma with a leather ball. This report highlights the potential blinding complication following rotational injury.
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Lesiones Oculares/complicaciones , Disco Óptico/lesiones , Traumatismos del Nervio Óptico/complicaciones , Oclusión de la Arteria Retiniana/etiología , Heridas no Penetrantes/complicaciones , Adolescente , Lesiones Oculares/diagnóstico , Humanos , Masculino , Disco Óptico/diagnóstico por imagen , Traumatismos del Nervio Óptico/diagnóstico , Oclusión de la Arteria Retiniana/diagnóstico , Tomografía Computarizada por Rayos X , Heridas no Penetrantes/diagnósticoRESUMEN
Metals that are active catalysts for methane (Ni, Pt, Pd), when dissolved in inactive low-melting temperature metals (In, Ga, Sn, Pb), produce stable molten metal alloy catalysts for pyrolysis of methane into hydrogen and carbon. All solid catalysts previously used for this reaction have been deactivated by carbon deposition. In the molten alloy system, the insoluble carbon floats to the surface where it can be skimmed off. A 27% Ni-73% Bi alloy achieved 95% methane conversion at 1065°C in a 1.1-meter bubble column and produced pure hydrogen without CO2 or other by-products. Calculations show that the active metals in the molten alloys are atomically dispersed and negatively charged. There is a correlation between the amount of charge on the atoms and their catalytic activity.
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This paper presents a low power monolithically integrated optical transmitter with avalanche mode light emitting diodes in a 140 nm silicon-on-insulator CMOS technology. Avalanche mode LEDs in silicon exhibit wide-spectrum electroluminescence (400 nm < λ < 850 nm), which has a significant overlap with the responsivity of silicon photodiodes. This enables monolithic CMOS integration of optocouplers, for e.g. smart power applications requiring high data rate communication with a large galvanic isolation. To ensure a certain minimum number of photons per data pulse (or per bit), light emitting diode drivers must be robust against process, operating conditions and temperature variations of the light emitting diode. Combined with the avalanche mode light emitting diode's steep current-voltage curve at relatively high breakdown voltages, this conventionally results in high power consumption and significant heating. The presented transmitter circuit is intrinsically robust against these issues, thereby enabling low power operation.
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This work presents a monolithic laterally-coupled wide-spectrum (350 nm < λ < 1270 nm) optical link in a silicon-on-insulator CMOS technology. The link consists of a silicon (Si) light-emitting diode (LED) as the optical source and a Si photodiode (PD) as the detector; both realized by vertical abrupt n+p junctions, separated by a shallow trench isolation composed of silicon dioxide. Medium trench isolation around the devices along with the buried oxide layer provides galvanic isolation. Optical coupling in both avalanche-mode and forward-mode operation of the LED are analyzed for various designs and bias conditions. From both DC and pulsed transient measurements, it is further shown that heating in the avalanche-mode LED leads to a slow thermal coupling to the PD with time constants in the ms range. An integrated heat sink in the same technology leads to a â¼ 6 times reduction in the change in PD junction temperature per unit electrical power dissipated in the avalanche-mode LED. The analysis paves way for wide-spectrum optical links integrated in smart power technologies.
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PURPOSE: To evaluate radiation dose reduction in patients undergoing transarterial chemoembolization with the use of a new image acquisition and processing platform. MATERIALS AND METHODS: Radiation-dose data were obtained from 176 consecutive chemoembolization procedures in 135 patients performed in a single angiography suite. From January 2013 through October 2013, 85 procedures were performed by using our institution's standard fluoroscopic settings. After upgrading the x-ray fluoroscopy system with an image acquisition and processing platform designed to reduce image noise and reduce skin entrance dose, 91 chemoembolization procedures were performed from November 2013 through December 2014. Cumulative dose-area product (CDAP), cumulative air kerma (CAK), and total fluoroscopy time were recorded for each procedure. Image quality was assessed by three interventional radiologists blinded to the x-ray acquisition platform used. RESULTS: Patient radiation dose indicators were significantly lower for chemoembolization procedures performed with the novel imaging platform. Mean CDAP decreased from 3,033.2 dGy·cm(2) (range, 600.3-9,404.1 dGy·cm(2)) to 1,640.1 dGy·cm(2) (range, 278.6-6,779.9 dGy·cm(2); 45.9% reduction; P < .00001). Mean CAK decreased from 1,445.4 mGy (range, 303.6-5,233.7 mGy) to 971.7 mGy (range, 144.2-3,512.0 mGy; 32.8% reduction; P < .0001). A 20.3% increase in mean total fluoroscopy time was noted after upgrading the imaging platform, but blinded analysis of the image quality revealed no significant degradation. CONCLUSIONS: Although a small increase in fluoroscopy time was observed, a significant reduction in patient radiation dose was achieved by using the optimized imaging platform, without image quality degradation.
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Angiografía/instrumentación , Quimioembolización Terapéutica/instrumentación , Fluoroscopía/instrumentación , Dosis de Radiación , Protección Radiológica/instrumentación , Radiografía Intervencional/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
OBJECTIVES: This study was undertaken to evaluate the viability of periodontal ligament (PDL) cells of avulsed teeth in three different storage media. MATERIALS AND METHODS: Forty-five premolars extracted for orthodontic therapeutic purposes were randomly and equally divided into three groups based on storage media used [Group I: milk (control); Group II: aloe vera (experimental); Group III: egg white (experimental)]. Following extractions, the teeth were placed in one of the three different storage media for 30 minutes, following which the scrapings of the PDL from these teeth were collected in Falcon tubes containing collagenase enzyme in 2.5 mL of phosphate buffered saline. The tubes were subsequently incubated for 30 minutes and centrifuged for five minutes at 800 rpm. The obtained PDL cells were stained with Trypan Blue and were observed under optical microscope. The percentage of viable cells was calculated. RESULTS: Aloe vera showed the highest percentage of viable cells (114.3±8.0), followed by egg white (100.9±6.3) and milk (101.1±7.3). CONCLUSION: Within the limitations of this study, it appears that aloe vera maintains PDL cell viability better than egg white or milk.