Prevalence of acute periapical abscesses in head and neck cancer patients receiving radiotherapy.

AIMS: Head and neck cancer is a serious condition affecting the life of patients. Radiotherapy is commonly used to treat such conditions. The aim of this study was to assess the prevalence of acute periapical abscesses (PAs) in patients who received radiotherapy for head and neck cancer. METHODS AND RESULTS: Data on acute PAs and oropharyngeal cancer (OPC) diagnosis with or without a history of radiation therapy (RAD) was retrieved by searching the appropriate query in the database. All cases were diagnosed for acute PAs by calibrated dentists for patients admitted to urgent care. The odds ratio (OR) for the prevalence of acute PAs and its association with a history of OPC with or without RAD were then calculated. Adjustment for comorbidities such as diabetes, smoking and gingival and periodontal diseases was also done. The prevalence of acute PAs in patients with a history of OPC was significantly higher as compared to the general hospital patient population (OR 2.92, 95%CI, p < .0001). Males were more affected than females and whites were more affected than African Americans and other ethnicities. The prevalence for PAs in patients with a history of OPC and RAD was higher and the difference in prevalence was statistically significant (OR 3.61, 95%CI, p < .0001). Whites were more affected than African Americans by more than 3.5-fold. Adjustment for diabetes comorbidly affected mainly the OPC + RAD group, however, the difference remained statistically significant. Adjustment for smoking and gingival and periodontal disease reduced the OR but the difference remained statistically different. CONCLUSIONS: The high prevalence of acute PAs in patients with a history of OPC and RAD may suggest an association between these conditions warranting a meticulous medical and dental examination.

Maxillary Sinusitis Induced by Medication-Related Osteonecrosis of the Jaw.

The involvement of maxillary sinuses in patients taking bone-related medications has not been comprehensively considered in the literature, mostly dental. Considering the fact that paranasal sinuses are often captured in dental radiographs, it is incumbent upon dental practitioners to recognize abnormal presentations in the paranasal sinuses to ensure the appropriate management of medication-related osteonecrosis of the jaw (MRONJ). We present a case of a giant cell tumor (GCT) with atypical chronic sinusitis manifestation leading to MRONJ.

Increased odds for COVID-19 infection among individuals with periodontal disease.

OBJECTIVES: Periodontal disease has been linked to multiple systemic conditions, but the relationship with COVID-19 still needs to be elucidated. We hypothesized that periodontal disease may be associated with COVID-19 infection. MATERIALS AND METHODS: This study utilized cross-sectional data to establish the strength of the association between periodontal disease and COVID-19 infection. The University of Florida Health Center's i2b2 patient's registry was used to generate patient counts through ICD-10 diagnostic codes. Univariate descriptive statistics of the patient population and logistic regression to estimate odds ratios of associations between periodontal disease and COVID-19 infection were used for analysis. RESULTS: Patients with periodontal disease were 4.4 times more likely to be positively diagnosed with COVID-19 than patients without PD. Associations remained similar and robust (P value < 0.0001) after adjustment for age (OR = 4.34; 95% CI, 3.68-5.09), gender (OR = 4.46; 95% CI, 3.79-5.23), and smoking status (OR = 4.77; 95% CI, 4.04-5.59). Associations were smaller but remained robust (P value < 0.0001) after adjusting for race (OR = 2.83; 95% CI, 2.40-3.32), obesity (OR = 2.53; 95% CI, 2.14-2.98), diabetes (OR = 3.32; 95% CI, 2.81-3.90), and cardiovascular disease (OR = 2.68; 95% CI, 2.27-3.14). CONCLUSIONS: Periodontal disease is significantly associated with increased odds for COVID-19 infection. CLINICAL RELEVANCE: With the caveat of a cross-sectional study design, these results suggest that periodontal disease may increase the odds for COVID-19 infection.

Effect of Selective Serotonin Reuptake Inhibitor (Paroxetine) on Newly Formed Bone Volume: Real-Time In Vivo Micro-computed Tomographic Analysis.

INTRODUCTION: Selective serotonin reuptake inhibitors (SSRIs) are commonly used to treat depression and anxiety. The purpose of this study was to assess in real time the effect of paroxetine, an SSRI, on newly formed bone volume (NFBV) in standardized calvarial defects (SCDs) in rats. METHODS: Fourteen Wistar albino female rats with a mean age of 7.5 months and a mean weight of 275 g were used. The animals were randomly divided into 2 groups. The experimental group was given paroxetine 8 weeks before the surgical procedure and throughout the experiment, and the control group was given a placebo 8 weeks before the surgical procedure and throughout the experiment. In each group, 14 SCDs measuring 4.6 mm in diameter were created on the parietal bone. In both groups, a Bio-Oss + collagen membrane was placed. All defects showed primary closure. The volume of the newly formed bone (NFBV) was measured using in vivo micro-computed tomographic imaging. Measurements were taken at days 0, 14, 28, 42, and 56 after surgery using real-time assessment with micro-computed tomographic imaging. RESULTS: The mean NFBV was 17.12 ± 4.52 mm3 and 12.52 ± 4.78 mm3 for the control and experimental groups, respectively, at day 56. The differences between the 2 groups were statistically significant (P < .05) at all time intervals. CONCLUSIONS: Paroxetine intake significantly reduced the amount of regenerated NFBV and the rate of new bone formation.

Effects of Crude Oil Properties and Dispersant on the Microstructure and Viscosity of Seawater-in-Oil Emulsions.

This study examines the effects of crude oil properties and dispersant concentration (Corexit 9500) on the evolution of bulk viscosity, viscoelastic properties, and microstructure of salt water-in-crude oil emulsions. Microscopy, followed by machine-learning-based analysis, provides the size and spatial distribution of the seawater droplets. The crude oils include light Bakken, Alaskan North Slope (ANS), and Louisiana oils, and medium to heavy Platform Henry, Cold Lake, and Platform Gina oils. The light and medium oils entrain water up to 80% by volume, and the heavy oils, up to 25%. The droplet sizes and distance between them decrease with increasing viscosity, with small droplets clustering around larger ones. The Bakken- and ANS-based emulsions are unstable, but all of the emulsions evolve in time. All exhibit a non-Newtonian behavior, with the viscosity decreasing with increasing shear rate. The storage modulus is higher than the loss modulus for light oils, and vice versa for heavy oils. Trends of their nondimensional viscosity are collapsed onto two power laws as a function of the Ohnesorge number involving the properties of the original oil, and the size or distance between droplets. For light oils, the power law exponent decreases with increasing capillary number based on the rheometer shear rate and increases for heavy oils. At high shear rates, the exponents converge to the same value, 0.45, suggesting that the oil viscosity becomes the property that defines the emulsion rheology. The present findings are consistent with previously published data. Premixing the emulsions with dispersant causes separation of most of the water from the light oils, leaving only sparse droplet concentrations. In contrast, owing to slow diffusion rate, only a small fraction of the seawater is extracted from the heavy oil emulsions. Hence, the sparse light oil emulsions become Newtonian, but the heavy ones remain non-Newtonian.

Localization and characterization of human papillomavirus-16 in oral squamous cell carcinoma.

OBJECTIVES: The role of Human papillomavirus (HPV) in the oral squamous cell carcinoma (OSCC) has not been completely elucidated. The purpose of the present study was to investigate the prevalence and localization of HPV-16 virus in OSCC and to correlate HPV-16 positivity and p16INK4A expression with the clinical and pathological features of OSCC. METHODS: The archives of Oral Pathology at the University of Florida, College of Dentistry were accessed for demographic, clinical, histopathological data, and slides of 114 OSCC patients. HPV-16 positivity of OSCC was evaluated by p16INK4A immunohistochemistry (IHC) and HPV-16 E6/E7mRNA by in situ hybridization (ISH). RESULTS: Out of 114 consecutive pathological slides of OSCC, 16 samples (14%) showed positivity for p16INK4A by IHC and 14 samples (12%) were positive for HPV-16 E6/E7mRNA ISH and the Positivity showed a significant correlation with the patients' age, alcohol consumption, and the degree of OSSC differentiation. The hard palate showed the highest positivity of p16INK4A IHC and HPV-16 mRNA ISH (38%, 36% respectively). CONCLUSION: HPV-16 is a significant factor in oral carcinogenesis. We recommend using p16INK4A as a surrogate marker for HPV detection in OSCC, which can be complemented by RNA ISH for the identification of HPV subtypes.

A lower prevalence of malignant lymphoma in Sjögren's syndrome patients: A cross-sectional study.

OBJECTIVE: This study aims to determine the prevalence and risk factors associated with lymphoma in primary Sjögren's syndrome (pSS). METHODS: We conducted a cross-sectional study on pSS patients who were registered into the Integrated Data Repository (IDR) at the University of Florida (UF) Health Shands Hospital. The parameters, such as age, sex, race, and smoking status, were included. Lymphoma types in pSS were categorized. The clinical and laboratory features were compared between pSS patients with and those without lymphoma by utilizing the items in the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI). RESULTS: Among 1,211,343 patients, we found 6799 patients (0.56%) with lymphomas and 2562 patients (0.21%) with pSS. Out of the 2562 pSS patients, 67 patients (2.6%) were diagnosed with lymphoma. The difference in the clinical and laboratory features listed under the ESSDAI domains between pSS patients with lymphomas and pSS without it was significant (p < 0.05 or 0.01): fever, weight loss, lymphadenopathy, splenomegaly, lacrimal gland diseases, cough, shortness of breath, hematuria, cerebrovascular accident diseases, peripheral nerve involvement due to vasculitis, neutropenia, and thrombocytopenia. CONCLUSION: We report 2.6% of lymphoma prevalence in pSS, lower than previously reported in the literature.

Increased Risk for Acute Periapical Abscesses in Multiple Sclerosis Patients and the Possible Association with Epstein-Barr Virus.

INTRODUCTION: Multiple sclerosis (MS) is a severe inflammatory neuroimmune degenerative condition affecting more than 2 million individuals worldwide. The purpose of this study was to assess the prevalence of acute periapical abscesses in patients with MS and to evaluate whether acute periapical abscesses (PAs) are more likely to affect patients who were previously infected by Epstein-Barr virus (EBV). METHODS: Integrated data of hospital patients were used. Data from the corresponding diagnosis codes for MS and acute PA were retrieved by querying the appropriate International Classification of Diseases, Tenth Revision codes in the database. RESULTS: Of the total hospital patient population, 0.18% were diagnosed with a history of MS. Females were more affected than males 3.25-fold. Whites were more affected than African Americans 6-fold. Whites were more affected than African Americans combined with other ethnicities 3.6-fold. The odds ratio (OR) for acute PAs in patients with a history of MS was 2.2 (P < .0001). After adjustment for diabetes mellitus comorbidity, the OR for acute PAs in patients with a history of MS was 2.6. After adjustment for cardiovascular disease comorbidity, the OR for acute PAs in patients with a history of MS was 1.27. Of the patients who presented with PAs, 0.2% were diagnosed with a history of EBV infection. The OR was 3.98, and the difference in prevalence was statistically significant (P < .0001). CONCLUSIONS: Under the conditions of this cross-sectional study, it appears that the prevalence of acute PAs is higher in patients with MS and that EBV may play a role.

Medication-Related Osteonecrosis of the Jaw in Cancer Patients: Result from the OneFlorida Clinical Research Consortium.

Medication-related osteonecrosis of the jaw (MRONJ) is a rare but severely debilitating drug-induced bone disorder in the jawbone region. The first MRONJ was reported in 2003 after bisphosphonate (BP) exposure. Recently, other drugs, such as receptor activator of NF-κB ligand (RANKL) inhibitor denosumab and antiangiogenic agents, were also associated with MRONJ. The purpose of this study was to evaluate the incidence and risk factors for MRONJ related to BPs or denosumab in cancer patients in real-world clinical settings using data from the OneFlorida Clinical Research Consortium. We queried the electronic health records of participants with prescriptions of intravenous (IV) BPs or denosumab between January 1, 2012, and September 1, 2021, in the OneFlorida Consortium. Time to MRONJ diagnosis was evaluated using the Kaplan-Meier method, and Cox regression analysis was performed to estimate the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for MRONJ. A total of 5689 participants had one or more prescriptions of IV BP or denosumab within this study period and were included in this study. Among these participants, 52 (0.9%) had a diagnosis of MRONJ. The overall rate of MRONJ was 0.73%, 0.86%, and 3.50% in the cancer patients treated with IV BPs, denosumab, and sequential IV BPs and denosumab, respectively. The risk of MRONJ was similar in participants treated with denosumab alone compared to those treated with IV BPs alone (HR: 1.25, 95% CI: 0.66-2.34, p = .49). Patients with sequential prescription of IV BP and denosumab were at much higher risk for MRONJ, with an adjusted HR of 4.49, 95% CI of 1.96-10.28, p = .0004. In conclusion, in real-world clinical settings, the rates of MRONJ associated with IV BPs and denosumab were similar, while the sequential treatment of these two drug classes was associated with a much higher risk of MRONJ. © 2022 American Society for Bone and Mineral Research (ASBMR).

Multiple oral squamous cell carcinoma 6 years after allogeneic stem cell transplantation complicated with chronic graft-versus-host disease: A case report.

Oral squamous cell carcinoma is a potential long-term complication after hematopoietic stem cell transplantation. This may be related to mechanisms including radiation and chemotherapy regimens, chronic graft-versus-host disease, inflammation, and prolonged immunosuppression. The current case describes the development of multiple oral white thick keratotic lesions in the floor of the mouth and the tongue 6 years after hematopoietic stem cell transplantation complicated with chronic graft-versus-host disease. A biopsy performed with histopathological analysis revealed a well-differentiated squamous cell carcinoma. The patient was treated by subtotal glossectomy, bilateral neck dissection, and flap reconstruction. This report highlights the significance of the routine oral examination of long-term surveillance post hematopoietic stem cell transplantation to ensure early detection of these tumors at potentially treatable stage.

Medication-related osteonecrosis of the jaw: A multifaceted diagnostic challenge. Mini review.

RESULTS: Medication-related osteonecrosis of the jaw (MRONJ) may present a challenge to the dental clinician due to the many presentations that it can have. This condition can be caused by multiple medications including bisphosphonates, RANKL ligand inhibitors and antiangiogenic drugs. Cases were reported in multiple sites of both the maxilla and mandible, including the hard palate, mylohyoid area, and the buccal plate. The risk factors for this condition include the use of a combination of antiresorptive medications, trauma, periodontal disease, immunosuppression, dental trauma, dental extractions, and bone manipulations. Spontaneous MRONJ have been reported in about half of the cases. Conventional radiographs are not conducive to a diagnosis, underscoring the importance of a three-dimensional modality in the diagnosis of MRONJ. The multifaceted diagnostic challenges of MRONJ are underscored in this mini review. CLINICAL SIGNIFICANCE: MRONJ can have diverse presentations and a lengthy multisite involvement. Therefore, long-term follow up for patients with history of use of antiresorptive medications is recommended.

Cerebral microcirculation mapped by echo particle tracking velocimetry quantifies the intracranial pressure and detects ischemia.

Affecting 1.1‰ of infants, hydrocephalus involves abnormal accumulation of cerebrospinal fluid, resulting in elevated intracranial pressure (ICP). It is the leading cause for brain surgery in newborns, often causing long-term neurologic disabilities or even death. Since conventional invasive ICP monitoring is risky, early neurosurgical interventions could benefit from noninvasive techniques. Here we use clinical contrast-enhanced ultrasound (CEUS) imaging and intravascular microbubble tracking algorithms to map the cerebral blood flow in hydrocephalic pediatric porcine models. Regional microvascular perfusions are quantified by the cerebral microcirculation (CMC) parameter, which accounts for the concentration of micro-vessels and flow velocity in them. Combining CMC with hemodynamic parameters yields functional relationships between cortical micro-perfusion and ICP, with correlation coefficients exceeding 0.85. For cerebral ischemia cases, the nondimensionalized cortical micro-perfusion decreases by an order of magnitude when ICP exceeds 50% of the MAP. These findings suggest that CEUS-based CMC measurement is a plausible noninvasive method for assessing the ICP and detecting ischemia.

Epithelial plasticity in COPD results in cellular unjamming due to an increase in polymerized actin.

The airway epithelium is subjected to insults such as cigarette smoke (CS), a primary cause of chronic obstructive pulmonary disease (COPD) and serves as an excellent model to study cell plasticity. Here, we show that both CS-exposed and COPD-patient derived epithelia (CHBE) display quantitative evidence of cellular plasticity, with loss of specialized apical features and a transcriptional profile suggestive of partial epithelial-to-mesenchymal transition (pEMT), albeit with distinct cell motion indicative of cellular unjamming. These injured/diseased cells have an increased fraction of polymerized actin, due to loss of the actin-severing protein cofilin-1. We observed that decreasing polymerized actin restores the jammed state in both CHBE and CS-exposed epithelia, indicating that the fraction of polymerized actin is critical in unjamming the epithelia. Our kinetic energy spectral analysis suggests that loss of cofilin-1 results in unjamming, similar to that seen with both CS exposure and in CHBE cells. The findings suggest that in response to chronic injury, although epithelial cells display evidence of pEMT, their movement is more consistent with cellular unjamming. Inhibitors of actin polymerization rectify the unjamming features of the monolayer. This article has an associated First Person interview with the first author of the paper.

Should anosmia and dysgeusia be a concern for oral and maxillofacial surgeons during the COVID-19 pandemic?

PURPOSE: Dysgeusia and anosmia have been liked to COVID-19 infection. The aim of this study is to study the prevalence of dysgeusia and anosmia in COVID-19 patients treated at the University of Florida Health Center and establish the odds of having an olfactory and gustatory disorder with a confirmed COVID-19 infection. METHODS: This is a retrospective cross-sectional study utilizing the University of Florida Health Center patients' registry i2b2 platform to search for ICD 10 diagnoses of COVID-19 infection and taste and smell disturbances. We assessed the odds ratio for patients with dysgeusia and anosmia having a laboratory-confirmed COVID-19 infection using a logistic regression model adjusting for gender, race, age, and comorbidity conditions. P < 0.05 was deemed significant. RESULTS: Out of 889 individuals that tested positive for COVID-19, 12.88% were diagnosed with taste and smell disturbances. The odds ratio for COVID-19 for people with dysgeusia and anosmia was 39.107. After adjusting for sex, age, and race, it was 41.9, 37, and 34.2, respectively. CONCLUSION: Taste and smell disturbances in COVID-19 are not anecdotal. It is paramount that oral and maxillofacial surgeons include taste and smell disturbances in the history and physical examination as these symptoms are suspicious of active COVID-19 infection. Patients presenting with an olfactory and gustatory disorder should undergo further evaluations for COVID-19 infection and oral and maxillofacial surgeons should enhance the personal protective equipment used when treating these patients to prevent further spread of the infection and protect other healthcare members.

Herpes simplex and herpes zoster viruses in COVID-19 patients.

BACKGROUND: Reactivation of herpes family viruses in immunocompromised patients may result in detrimental outcomes for the hosts; therefore, herpes simplex virus-1 and varicella zoster virus infections in the context of COVID-19 may have clinical and prognostic implications. Several reports associated this human herpes virus with COVID-19 infection and have claimed that it can be an indicator for latent COVID-19 infection. However, since most of these were case reports, it is impossible to assess the prevalence of these associations. METHODS: The University of Florida patient registry i2b2 with ICD-10 diagnosis codes was used for retrieval of patients with diagnosis of COVID-19 and each of the other viruses over the period of October 2015-June 2020. RESULTS: The prevalence of the herpes simplex-1 occurrence in the COVID-19 group was 2.81% compared to 0.77% in the hospital population odds ratio of 5.27. When adjusted for gender, race, and age, the odds were 5.18, 4.48, and 4.61, respectively. After adjustment for respiratory disease, endocrine disease, obesity, diabetes, circulatory disease, and smoking, the odds were 1.94, 3.18, 1.37, 3.54, 3.7, and 5.1, respectively. The prevalence of the varicella zoster virus in COVID-19 patients was 1.8% compared to 0.43% in the hospital population, odds ratio of 5.26 before adjustment, and 5.2, 5.47, and 4.76 after adjusting for gender, age, and race, respectively. When adjusted for respiratory disease, endocrine disease, obesity, diabetes, and circulatory and neurological diseases, the odds were 1.3, 2.2, 1.48, 2.33, 2.85, and 2.6, respectively. CONCLUSION: Herpes simplex-1 and varicella zoster viruses are strongly associated with COVID-19 infection.

Effect of Oil Properties on the Generation of Nano-Aerosols During Bubble Bursting Through Crude Oil-Dispersant Slicks.

This study examines the effect of dispersant and oil properties on the aerosolization of fresh and weathered surface crude oil slicks by bursting of a plume of ∼0.7 mm bubbles. A scanning mobility particle sizer measures the size distribution of aerosols in the 20-400 nm range in a clean air chamber. The 500-µm-thick slicks contain oils with varying origin, viscosity, interfacial tension, and weathering state. Test are performed with and without premixed dispersant (Corexit 9500A), which reduces the oil-seawater interfacial tension by 2 orders of magnitude at a dispersant-to-oil ratio (DOR) of 1:25. When compared to aerosolization in clean seawater, the nano-aerosol concentration decreases for slicks without dispersant but increases by 27%-351% upon introduction of dispersant. For most cases, the airborne nanodroplet concentration increases with decreasing Capillary or Morton numbers as well as the ratio of the so-called inner to thermal length scales. To explain the airborne nanodroplet generation in an oil-dispersant mixture, we show that prior to bubble injection, even minimal agitation of the interface causes generation of a subsurface cloud of nanodroplets that diffuses away from the interface. This process appears to be caused by thermal capillary instability when the interfacial tension is low enough to increase the thermal length scale to a few nanometers.

Genome-wide Association Study Identified Chromosome 8 Locus Associated with Medication-Related Osteonecrosis of the Jaw.

Medication-related osteonecrosis of the jaw (MRONJ) is a rare but serious drug-related adverse event. To identify pharmacogenomic markers of MRONJ associated with bisphosphonate therapy, we conducted a genomewide association study (GWAS) meta-analysis followed by functional analysis of 5,008 individuals of European ancestry treated with bisphosphonates, which includes the largest number of MRONJ cases to date (444 cases and 4,564 controls). Discovery GWAS was performed in randomly selected 70% of the patients with cancer and replication GWAS was performed in the remaining 30% of the patients with cancer treated with intravenous bisphosphonates followed by meta-analysis of all 3,639 patients with cancer. GWAS was also performed in 1,369 patients with osteoporosis treated with oral bisphosphonates. The lead single-nucleotide polymorphism (SNP), rs2736308 on chromosome 8, was associated with an increased risk of MRONJ with an odds ratio (OR) of 2.71 and 95% confidence interval (CI) of 1.90-3.86 (P = 3.57*10-8 ) in the meta-analysis of patients with cancer. This SNP was validated in the MRONJ GWAS in patients with osteoporosis (OR: 2.82, 95% CI: 1.55-4.09, P = 6.84*10-4 ). The meta-analysis combining patients with cancer and patients with osteoporosis yielded the same lead SNP rs2736308 on chromosome 8 as the top SNP (OR: 2.74, 95% CI: 2.09-3.39, P = 9.65*10-11 ). This locus is associated with regulation of the BLK, CTSB, and FDFT1 genes, which had been associated with bone mineral density. FDFT1 encodes a membrane-associated enzyme, which is implicated in the bisphosphonate pathway. This study provides insights into the potential mechanism of MRONJ.

Prevalence of candidiasis and oral candidiasis in COVID-19 patients: a cross-sectional pilot study from the patients' registry in a large health center.

OBJECTIVE: Candida albicans in considered to be a marker of immunosuppression in serious chronic condition such as HIV and cancer patients on immunosuppresion medications. The new COVID-19 pandemic has caused acute respiratory distress syndrome in many patients, which poses a risk of super-infections including Candida strains causing oral candidiasis as well as invasive fungal infections. The aim of the study was to examine the association between COVID-19 and oral and general candidiasis. METHOD AND MATERIALS: The i2b2 data repository platform was used to analyze the interrelations between COVID-19, oral candidiasis, and total candidiasis in a hospital population. ICD diagnoses codes were used to generate queries on total numbers and demographic data on COVID-19, oral candidasis, total candidasis, and COVID-19 with each form of candidasis. RESULTS: From the 889 patients diagnosed with COVID-19, 106 (12%) were diagnosed with candidiasis at large and 14 (1.6%) had oral candidiasis. The odds ratio (OR) for COVID-19 in the presence of oral candidiasis was 2.01 (95% CI 1.1870 to 3.4143, P = .094) and the OR for COVID-19 in the presence of candidiasis was 3.73 (95% CI 3.0419 to 4.5847, P < .0001 ). African American were disproportionally affected and comprised about 40% of the COVID-19/candidiasis groups. CONCLUSIONS: Total candidiasis was significantly associated with increased risk for COVID-19, whereas oral candidiasis showed an insignificant trend. The dental practitioner should be aware of the importance of unexplained oral and systemic candidiasis as a potential harbinger of T and B cell immunosuppression associated with viral in-fections. COVID-19 may be a risk factor for total candidiasis.

Time Evolution and Effect of Dispersant on the Morphology and Viscosity of Water-In-Crude-Oil Emulsions.

This study examines the time evolution and effects of adding dispersant (Corexit 9500A) at varying concentrations on the microscopic morphology and bulk viscosity of saltwater-in-crude-oil (Louisiana) mechanically mixed emulsions. Rheology is used for measuring the viscoelastic properties and viscosity, the latter at varying shear rates. Microscopy, followed by machine-learning-based analysis, is used for characterizing the size and spatial distribution of the water droplets in the emulsions. Initially, the water droplets appear as a multiscale lattice with a Sauter diameter of 5.3 µm and a polydispersity of 0.43, with small droplets aggregating around large ones. The corresponding bulk viscosity decreases with increasing shear rate from 2 orders of magnitude to 5 times higher than that of the weathered crude oil. After 7 days, the number of submicron droplets increases, the nearest-neighbor distance decreases, indicating preferential aggregation, and the viscosity increases by 56-112% at high shear rates (5-100 s-1). After 14 and 21 days, some droplets coalesce resulting in loss of clusters and a decrease in viscosity. These trends suggest that changes in the aggregation contribute to the variations in viscosity. Subsequent analysis applies previously developed models for the effect of aggregation on the properties of the emulsion. While the reduction in viscosity is predicted by this model, matching of rates requires modification to the assumed relationship between yield stress and interdroplet forces. Adding dispersant without mixing generates Marangoni-driven flows as the water droplets coalesce. In time, part of the water separates, a fraction forms clouds of submicron droplets, and the rest remains unchanged. Mixing dispersant at low concentration with the emulsion accelerates the coalescence and phase separation. The removed water fraction increases with dispersant concentration, reaching 99.6% for a dispersant-to-emulsion concentration of 10-3. The remaining emulsion consists of fine droplets with Newtonian viscosity that is still 4 times higher than that of the fresh crude oil but only 14% higher than that of the weathered oil.