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1.
J Phys Chem B ; 127(36): 7748-7757, 2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37647302

ABSTRACT

The comprehension of silicate oligomer formation during the initial stage of zeolite synthesis is of significant importance. In this study, we investigated the effect of chloride ions (Cl-) on silicate oligomerization using ab initio molecular dynamics simulations with explicit water molecules. The results show that the presence of Cl- increases the free energy barriers of all reactions compared to the case without the anion. The formation of the 4-ring structure has the lowest free energy barrier (73 kJ/mol), while the formation of the 3-ring structure has the highest barrier (98 kJ/mol) in the presence of Cl-. These findings suggest that Cl- suppresses the formation of 3-rings and favors the formation of larger oligomers in the process of zeolite synthesis. Our study provides important insights into the directing role of Cl- in silicate oligomerization by regulating thermodynamic and kinetic parameters. An important point to consider is the impact of the anion on aqueous reactions, particularly in altering the hydrogen bond network around reactive species. These results also provide a basis for further studies of the formations of larger silicate oligomers in solution.

2.
J Investig Med High Impact Case Rep ; 11: 23247096231181867, 2023.
Article in English | MEDLINE | ID: mdl-37341445

ABSTRACT

A barium esophagram is a diagnostic test used for the evaluation of dysphagia. However, this test has the potential risk for aspiration of the barium contrast. Barium aspiration typically localizes to the right lower lobe or left lingular lobe. We present a case of barium aspiration localized to the right middle lobe that persisted on chest X-ray. A 62-year-old male with a past medical history of hypertension, long-term back pain, gastritis, and anxiety presented with the complaints of hoarseness of voice, dysphagia, and weight loss for several months. During the esophagram, the patient aspirated the barium contrast. Chest X-ray confirmed the aspiration in the right middle lobe with a tree in bud appearance suggesting involvement of bronchioles. Three months later, a repeat chest X-ray revealed residual contrast. Pulmonary complications are directly related to the amount of aspirated barium and can include hypoxia, respiratory failure, secondary aspiration pneumonia, shock, and acute respiration distress syndrome. The prognosis of a barium aspiration is dependent on the amount of barium aspirated.


Subject(s)
Deglutition Disorders , Pneumonia, Aspiration , Respiratory Distress Syndrome , Humans , Middle Aged , Barium/adverse effects , Deglutition Disorders/diagnostic imaging , Deglutition Disorders/etiology , Hypoxia , Pneumonia, Aspiration/diagnostic imaging , Pneumonia, Aspiration/etiology
3.
Phys Chem Chem Phys ; 25(18): 12723-12733, 2023 May 10.
Article in English | MEDLINE | ID: mdl-37114395

ABSTRACT

The formation of silicate oligomers in the early stages is key to zeolite synthesis. The pH and the presence of hydroxide ions are important in regulating the reaction rate and the dominant species in solutions. This paper describes the formation of silicate species, from dimers to 4-membered rings, using ab initio molecular dynamics simulations in explicit water molecules with an excess hydroxide ion. The thermodynamic integration method was used to calculate the free energy profile of the condensation reactions. The hydroxide group's role is not only to control the pH of the environment, but also to actively participate in the condensation reaction. The results show that the most favorable reactions are linear-tetramer and 4-membered-ring formation, with overall barriers of 71 kJ mol-1 and 73 kJ mol-1, respectively. The formation of trimeric silicate, with the largest free-energy barrier of 102 kJ mol-1, is the rate-limiting step under these conditions. The excess hydroxide ion aids in the stabilization of the 4-membered-ring structure over the 3-membered-ring structure. Due to a relatively high free-energy barrier, the 4-membered ring is the most difficult of the small silicate structures to dissolve in the backward reaction. This study is consistent with the experimental observation that silicate growth in zeolite synthesis is slower in a very-high-pH environment.

4.
J Investig Med High Impact Case Rep ; 10: 23247096221127100, 2022.
Article in English | MEDLINE | ID: mdl-36154322

ABSTRACT

Pneumoconiosis is associated with coal dust particles depositing within the lung causing nodules coalesce to form progressive massive fibrosis (PMF). Cavitary lesions can develop in these PMF areas for concerns of tuberculosis and aspergillosis. We present a 59-year-old patient who had coal workers pneumoconiosis and PMF presenting with chronic dyspnea and hemoptysis with an upper cavitary lesion noted on chest imaging. He notes dyspnea with walking very short distances with associated productive cough. He admits to occasional wheezing, paroxysmal dyspnea, hemoptysis, and orthopnea but denies chest pain. He is an everyday smoker. His physical examination was only remarkable for bronchial breath sounds. On review of his prior imaging, he had a right upper lobe infiltrate as far back as 2012. As the years progressed, a new cavitary lesion developed in the PMF area which progressively got larger with a thick wall and no eccentric region noted inside the cavity. Tuberculosis test was negative. He underwent a transbronchial biopsy with methenamine silver stain which showed acute angle branching and septation suggestive of Aspergillus species. He was diagnosed with pulmonary aspergillosis and treated with voriconazole for 1 year. With pneumoconiosis and evidence confirming aspergillosis, the presence of a new lung infiltration with progression into a cavitary lesion leads to a diagnosis of chronic cavitary pulmonary aspergillosis (CCPA). With follow-up imaging showing extensive lung fibrosis, he had chronic fibrosing pulmonary aspergillosis (CFPA), a late-stage manifestation of CCPA.


Subject(s)
Anthracosis , Aspergillosis , Pneumoconiosis , Pulmonary Aspergillosis , Anthracosis/complications , Anthracosis/diagnosis , Aspergillosis/complications , Coal , Dust , Dyspnea/etiology , Fibrosis , Hemoptysis/etiology , Humans , Male , Methenamine , Middle Aged , Pneumoconiosis/complications , Pneumoconiosis/etiology , Pulmonary Aspergillosis/complications , Pulmonary Aspergillosis/diagnosis , Pulmonary Aspergillosis/drug therapy , Voriconazole
5.
Cureus ; 14(7): e26555, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35936145

ABSTRACT

The cytokine storm associated with coronavirus disease 2019 (COVID-19) triggers a hypercoagulable state leading to venous and arterial thromboembolism. Lab findings associated with this phenomenon are elevated D-dimer, fibrinogen, C-reactive protein (CRP), ferritin, and procalcitonin. We present the case of a 66-year-old male with dyslipidemia who was diagnosed with COVID-19 with worsening shortness of breath, myalgia, and loss of taste. Physical examination was remarkable for crackles with diminished lung sounds and use of his accessory muscles. Labs showed normal white blood cell count, D-dimer of 1.42 mg/L, ferritin of 961 ng/mL, lactate dehydrogenase (LDH) of 621 U/L, and CRP of 2.1 mg/dL. Chest X-ray showed atypical pneumonitis with patchy abnormalities. He required oxygen supplementation with fraction of inspired oxygen of 100% proning as tolerated. He received remdesivir, ceftriaxone, azithromycin, dexamethasone, prophylactic enoxaparin, and a unit of plasma therapy. His D-dimer had increased from 1.65 to 3.51 mg/L with worsening dyspnea. At this time, computed tomography angiogram (CTA) of the chest showed extensive ground-glass opacities and a 2.4 × 1.9 × 1.3 cm distal thoracic aortic intraluminal thrombus. He was started on a heparin drip. A follow-up CTA of the aorta showed thrombus or hypoattenuation within the splenic artery and wedge-shaped areas extending from the hilum with possible infarction and a 6 mm thrombus in the infrarenal abdominal aorta. He was transitioned to enoxaparin 1 mg/kg twice daily. He remained asymptomatic from his splenic infarction. This case adds more insight to splenic infarction associated with COVID-19 in addition to the 32 reported cases documented thus far. Management of thromboembolism includes a therapeutic dose of anticoagulation. To prevent thromboembolism, prophylactic anticoagulation is recommended for those hospitalized with COVID-19.

6.
IEEE Trans Med Imaging ; 41(6): 1443-1453, 2022 06.
Article in English | MEDLINE | ID: mdl-34990354

ABSTRACT

Deformable registration is a crucial step in many medical procedures such as image-guided surgery and radiation therapy. Most recent learning-based methods focus on improving the accuracy by optimizing the non-linear spatial correspondence between the input images. Therefore, these methods are computationally expensive and require modern graphic cards for real-time deployment. In this paper, we introduce a new Light-weight Deformable Registration network that significantly reduces the computational cost while achieving competitive accuracy. In particular, we propose a new adversarial learning with distilling knowledge algorithm that successfully leverages meaningful information from the effective but expensive teacher network to the student network. We design the student network such as it is light-weight and well suitable for deployment on a typical CPU. The extensively experimental results on different public datasets show that our proposed method achieves state-of-the-art accuracy while significantly faster than recent methods. We further show that the use of our adversarial learning algorithm is essential for a time-efficiency deformable registration method. Finally, our source code and trained models are available at https://github.com/aioz-ai/LDR_ALDK.


Subject(s)
Algorithms , Image Processing, Computer-Assisted , Humans , Image Processing, Computer-Assisted/methods , Software
7.
J Investig Med High Impact Case Rep ; 10: 23247096211063332, 2022.
Article in English | MEDLINE | ID: mdl-34984948

ABSTRACT

We present the case of a 56-year-old woman who was diagnosed with severe coronavirus disease 2019 (COVID-19) pneumonia complicated by severe acute respiratory distress syndrome who was intubated for 19 days. She recovered from COVID-19 after a month. A computed tomography (CT) scan of the chest, after a month, showed improved infiltrates with a small residual cavity within the lingula. A CT angiogram showed a more confluent density in the lingular portion on follow-up 2 months later. She developed intermittent hemoptysis after 3 months in December 2020, which persisted for almost 6 months, and CT of the chest showed the lingular nodular with resolution of the cavitation. She underwent bronchoscopy with bronchoalveolar lavage, confirming Aspergillus fumigatus by galactomannan assay and histology showing branching hyphae. Once she started treatment with itraconazole, her hemoptysis resolved. The follow-up CT of the chest after 2 months of treatment did not show a cavity or a nodule in the lingula. Our patient developed invasive pulmonary aspergillosis (IPA) as a sequela of severe COVID-19 infection. COVID-19-associated invasive pulmonary aspergillosis (CAPA) is an underrecognized complication that needs to be investigated on whether prophylactic treatment is required. Our case also demonstrates that the diagnosis of IPA needs to be considered months after COVID-19 infection when a superimposed fungal infection can occur after a viral infection if the patient continues to have persistent symptoms.


Subject(s)
COVID-19 , Invasive Pulmonary Aspergillosis , Pulmonary Aspergillosis , Aspergillus fumigatus , Female , Humans , Invasive Pulmonary Aspergillosis/complications , Invasive Pulmonary Aspergillosis/diagnosis , Invasive Pulmonary Aspergillosis/drug therapy , Middle Aged , Pulmonary Aspergillosis/complications , Pulmonary Aspergillosis/drug therapy , SARS-CoV-2
8.
Cureus ; 13(11): e19726, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34934589

ABSTRACT

Immunotherapy is on the rise as a treatment option for advanced melanoma, non-small cell lung carcinoma, renal cell carcinoma, and melanoma among others. It consists of two main classes being cytotoxic T lymphocyte antigen 4 (CTLA 4) inhibitors and programmed cell death 1 (PD 1) inhibitors. We report a case series of four patients who were started on either pembrolizumab or nivolumab for the treatment of melanoma or lung cancer. While on immunotherapy, they developed various side effects related to the immunotherapy including pneumonitis, transaminitis, thyroiditis, nephritis, and hypophysitis. To treat this complication, immunotherapy must be discontinued or held with immunosuppressant initiation as treatment. Most often the immunosuppressant of choice is steroids. After symptoms improve, patients can decide along with the clinician on restarting or completely stopping immunotherapy. Within our case series, three of four patients had resolutions of their symptoms with steroid treatment with one who was lost to follow up. Of the three patients who were being followed up, one had a relapse of side effects after resuming immunotherapy and decided against further treatment with immunotherapy. Another patient is doing well resuming immunotherapy on a daily dose of steroids. The last patient decided to not continue with immunotherapy after experiencing a flare of his symptoms when he was being treated since he missed a few doses of steroids. Further research is needed about the risk of flares of complications when resuming immunotherapy alone or with immunotherapy and steroid treatment.

9.
Cureus ; 13(8): e16842, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34513428

ABSTRACT

Introduction The success of a vaccination program is dependent on vaccine efficacy and the number of people vaccinated. Healthcare workers are the first to receive the COVID-19 vaccine based on CDC phase 1a recommendations and are a point of contact for information for patients, so they must be well-educated on common misconceptions about the vaccine. Objective To identify acceptance/refusal rates of COVID-19 vaccine, reasons for refusal, and to understand the impact of demographics, work environment, and comorbidities on vaccine acceptance. Methods A cross-sectional study of 1076 healthcare employees in Rural Appalachian utilizing electronic and paper-based 12 question surveys from December 10, 2020, through December 20, 2020, followed up to April 2021. Results Within our study, 52.3% of our healthcare workers would accept vaccination with higher age, male gender, physicians, and those who receive annual flu vaccines more likely to accept vaccination. The most common reason for refusal was unknown side effects (88.5%). The second reason for refusal at 33.5% was waiting for someone else to take the vaccine first. In February 2021, the percentage of our healthcare workers who were vaccinated was 48%, which then increased to 55% in March 2021. By April 2021, the vaccination percentage of our healthcare workers reached 59%. Conclusions In order to predict how the public percentage of vaccination would be, healthcare workers need to address concerns about side effects from the vaccines and encourage the public to get the vaccines since healthcare workers themselves had already received the vaccines and can educate the patients on how they did after getting the shots.

10.
J Investig Med High Impact Case Rep ; 9: 23247096211029744, 2021.
Article in English | MEDLINE | ID: mdl-34229452

ABSTRACT

We report a rare case of a 32-year-old male who ingested 32.4 to 54 mg of colchicine and presented after 44 hours. He developed progressive multiple organ failure with shock, acute kidney failure, troponemia, pancytopenia, absolute neutropenia, disseminated intravascular coagulation, acute liver failure, rhabdomyolysis, and lactic acidosis. He also developed electrolyte abnormalities and refractory hypoglycemia. Initial treatment consisted of activated charcoal, fluids, and broad-spectrum antibiotics with supportive treatment of mechanical ventilation, hemodialysis, vasopressors, N-acetylcysteine, colony-stimulating factors, and blood products. Literature shows potential benefit of colchicine-specific Fab fragments for acute toxicity with limited studies and is not currently available in the United States. Further research for N-acetylcysteine protocol for acute liver failure in colchicine toxicity and potential use of colchicine-specific Fab fragments is needed. Our case demonstrates the importance of early use of activated charcoal for ingestion overdose with the incorporation of poison control into multidisciplinary team for coordinated patient care.


Subject(s)
Acute Kidney Injury , Drug Overdose , Pancytopenia , Adult , Colchicine/adverse effects , Humans , Male , Multiple Organ Failure
11.
J Investig Med High Impact Case Rep ; 9: 23247096211026144, 2021.
Article in English | MEDLINE | ID: mdl-34148400

ABSTRACT

Chylothorax is a pleural effusion of >110 mg/dL of triglycerides with a milky appearance with transudative being rare. In this article, we present a case of transudative chylothorax with concurrent chylous ascites that is secondary to congestive heart failure (CHF). A 70-year-old male with CHF with ejection fraction of 10%, coronary artery disease status post coronary artery bypass graft, sleep apnea, chronic kidney disease stage 3, and chronic obstructive pulmonary disease presented with worsening abdominal distention, shortness of breath, and increased lower extremities edema. He denied any cough or fever but had orthopnea and paroxysmal nocturnal dyspnea. He requires monthly paracentesis with drainage of 5 to 9 L each time. On physical examination, he had crackles bilaterally with no wheezes or jugular venous distension. His cardiac examination was unremarkable. He did have abdominal distension with dullness to percussion and a positive fluid wave. There was +2 bilateral pitting edema of lower extremities. He had a diagnostic paracentesis where 9.2 L of cloudy milky fluid was drained and therapeutic thoracentesis where 1.1 L of milky fluid was drained. Pleural fluid for triglycerides was 280. His peritoneal fluid had triglycerides of 671 confirming chylous ascites. CHF can lead to chylous ascites due to the increased lymph production in the abdomen, which flows to the thoracic duct. Due to the stiffness at the lymphatic junction, there is high pressure for less flow. The diaphragm plays a role allowing the chylous ascites to be absorb into the thorax.


Subject(s)
Chylothorax , Chylous Ascites , Heart Failure , Pleural Effusion , Aged , Ascitic Fluid , Chylothorax/etiology , Chylothorax/therapy , Chylous Ascites/etiology , Chylous Ascites/therapy , Heart Failure/etiology , Humans , Male , Pleural Effusion/etiology
12.
Comput Intell Neurosci ; 2019: 1483294, 2019.
Article in English | MEDLINE | ID: mdl-31396268

ABSTRACT

Object retrieval plays an increasingly important role in video surveillance, digital marketing, e-commerce, etc. It is facing challenges such as large-scale datasets, imbalanced data, viewpoint, cluster background, and fine-grained details (attributes). This paper has proposed a model to integrate object ontology, a local multitask deep neural network (local MDNN), and an imbalanced data solver to take advantages and overcome the shortcomings of deep learning network models to improve the performance of the large-scale object retrieval system from the coarse-grained level (categories) to the fine-grained level (attributes). Our proposed coarse-to-fine object retrieval (CFOR) system can be robust and resistant to the challenges listed above. To the best of our knowledge, the new main point of our CFOR system is the power of mutual support of object ontology, a local MDNN, and an imbalanced data solver in a unified system. Object ontology supports the exploitation of the inner-group correlations to improve the system performance in category classification, attribute classification, and conducting training flow and retrieval flow to save computational costs in the training stage and retrieval stage on large-scale datasets, respectively. A local MDNN supports linking object ontology to the raw data, and an imbalanced data solver based on Matthews' correlation coefficient (MCC) addresses that the imbalance of data has contributed effectively to increasing the quality of object ontology realization without adjusting network architecture and data augmentation. In order to evaluate the performance of the CFOR system, we experimented on the DeepFashion dataset. This paper has shown that our local MDNN framework based on the pretrained NASNet architecture has achieved better performance (14.2% higher in recall rate) compared to single-task learning (STL) in the attribute learning task; it has also shown that our model with an imbalanced data solver has achieved better performance (5.14% higher in recall rate for fewer data attributes) compared to models that do not take this into account. Moreover, MAP@30 hovers 0.815 in retrieval on an average of 35 imbalanced fashion attributes.


Subject(s)
Computer Simulation , Deep Learning , Neural Networks, Computer , Problem Solving , Biological Ontologies , Humans , Resource Allocation
13.
Molecules ; 21(3): 329, 2016 Mar 09.
Article in English | MEDLINE | ID: mdl-27005608

ABSTRACT

Chemically diverse heterocyclic chalcones were prepared and evaluated for cytotoxicity, aiming to push forward potency and selectivity. They were tested against rhabdomyosarcoma (RMS) and noncancerous cell line (LLC-PK1). The influence of heteroaryl patterns on rings A and B was studied. Heterocycle functionalities on both rings, such as phenothiazine, thiophene, furan and pyridine were evaluated. Notably, the introduction of three methoxy groups at positions 3, 4, 5 on ring B appears to be critical for cytotoxicity. The best compound, with potent and selective cytotoxicity (IC50 = 12.51 µM in comparison with the value 10.84 µM of paclitaxel), contains a phenothiazine moiety on ring A and a thiophene heterocycle on ring B. Most of the potential compounds only show weak cytoxicity on the noncancerous cell line LLC-PK1.


Subject(s)
Cell Proliferation/drug effects , Chalcones/pharmacology , Heterocyclic Compounds/pharmacology , Rhabdomyosarcoma/drug therapy , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Chalcones/chemical synthesis , Chalcones/chemistry , Heterocyclic Compounds/chemical synthesis , Heterocyclic Compounds/chemistry , Humans , Molecular Structure , Structure-Activity Relationship , Swine
14.
Bioorg Med Chem Lett ; 22(14): 4555-60, 2012 Jul 15.
Article in English | MEDLINE | ID: mdl-22727643

ABSTRACT

A total of 30 chalcone analogues was synthesized via a base catalyzed Claisen Schmidt condensation and screened for their in vitro antibacterial activity against Methicillin-sensitive Staphylococcus aureus (MSSA) and Methicillin-resistant Staphylococcus aureus (MRSA) alone or in combination with non beta-lactam antibiotics namely ciprofloxacin, chloramphenicol, erythromycin, vancomycin, doxycycline and gentamicin. In the checkerboard technique, fractional inhibitory concentration indices (FICI) show that the following combinations like ciprofloxacin with 25 (4'-bromo-2-hydroxychalcone); doxycycline with 21 (4-hydroxychalcone); doxycycline with 25; and doxycycline with 4 (2',2-dihydroxychalcone) were synergistic against MRSA. In term SAR study, the relationship between chalcone structure and their antibacterial activity against S. aureus and synergy with tested antibiotics were discussed. Possible mechanisms for antibacterial activity of chalcones alone as well as the synergistic effect in combinations were proposed by molecular modeling studies, respectively. Combinations of chalcones with conventional antibiotics could be an effective alternative in the treatment of infection caused by MRSA.


Subject(s)
Anti-Bacterial Agents/chemical synthesis , Methicillin-Resistant Staphylococcus aureus/drug effects , beta-Lactams/chemical synthesis , Anti-Bacterial Agents/pharmacology , Models, Molecular , Molecular Structure , Structure-Activity Relationship , beta-Lactams/pharmacology
15.
Molecules ; 17(6): 6684-96, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22728362

ABSTRACT

A series of simple heterocyclic chalcone analogues have been synthesized by Claisen Schmidt condensation reactions between substituted benzaldehydes and heteroaryl methyl ketones and evaluated for their antibacterial activity. The structures of the synthesized chalcones were established by IR and ¹H-NMR analysis. The biological data shows that compounds p5, f6 and t5 had strong activities against both susceptible and resistant Staphylococcus aureus strains, but not activity against a vancomycin and methicillin resistant Staphylococcus aureus isolated from a human sample. The structure and activity relationships confirmed that compounds f5, f6 and t5 are potential candidates for future drug discovery and development.


Subject(s)
Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Chalcone/chemical synthesis , Chalcone/pharmacology , Anti-Bacterial Agents/chemistry , Chalcone/analogs & derivatives , Chalcone/chemistry , Drug Synergism , Microbial Sensitivity Tests , Staphylococcus aureus/drug effects , Structure-Activity Relationship
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