Nasopharyngeal Region Research Articles

Comparative study of optical coherence tomograph and histological images of eustachian tube nasopharyngeal region and adjacent structures in vivo and ex-vivo miniature pigs

ObjectivesOptical Coherence Tomograph (OCT) imaging technology can be used to examine, in vivo, the human ET. At present, it is impossible to achieve the OCT scanning vivo and ex vivo in the same individual human body, or study the consistency between OCT images and histological images of the eustachian tube nasopharyngeal region and adjacent structures. The aim of this study was to determine the consistency between OCT images and histological sections in vivo and ex vivo in miniature pigs.MethodsOCT imaging was performed on five adult miniature pigs in vivo and ex vivo. The images of the eustachian tube OCT (ET-OCT), nasopharynx OCT (NP-OCT) and histological cross sections were further studied.ResultsAll five miniature pigs achieved the OCT scan successfully, acquiring ET-OCT and NP-OCT images in vivo and ex vivo on both sides. The acquired ET OCT images closely matched the histological images, revealing details of the cartilage, submucosa, glands, and mucosa. The lower segment of the ET wall mucosa had an abundance of glands and submucosal tissues, with more low-signal areas appearing in the ex vivo images. The NP-OCT images of the nasopharynx matched the details of the mucosa and submucosal tissues. The ex-vivo OCT images showed thicker mucosa and more scattered slightly lower signal areas compared to the vivo OCT images.ConclusionsET-OCT images and NP-OCT images matched the histological structure of eustachian tube nasopharyngeal region structures in miniature pigs both in vivo and ex vivo. OCT images may be sensitive to changes in edema and ischemia status. There is a great potential for morphological assessment of inflammation, edema, injure, mucus gland status.

CDC25A inhibition suppresses cell proliferation and induces G1/S‑phase cell cycle arrest in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is a primary malignancy that originates from the nasopharyngeal region. It has been demonstrated that a decrease in the expression level of cell division cycle gene 25A (CDC25A) suppresses cell viability and induces apoptosis in a variety of different types of cancer. However, at present, the role of CDC25A in NPC has yet to be fully elucidated. Therefore, the aim of the present study was to investigate the role of CDC25A in NPC progression and to explore the potential underlying mechanism. Reverse transcription‑quantitative PCR was performed to detect the relative mRNA levels of CDC25A and E2F transcription factor 1 (E2F1). Western blot analysis was subsequently used to determine the expression levels of CDC25A, Ki67, proliferating cell nuclear antigen (PCNA) and E2F1. CCK8 assay was employed to measure cell viability and flow cytometric analysis was employed to analyze the cell cycle. The binding sites between the CDC25A promoter and E2F1 were predicted using bioinformatics tools. Finally, luciferase reporter gene and chromatin immunoprecipitation assays were performed to verify the interaction between CDC25A and E2F1. The results obtained suggested that CDC25A is highly expressed in NPC cell lines and CDC25A silencing was found to inhibit cell proliferation, reduce the protein expression levels of Ki67 and PCNA and induce G1 arrest of NPC cells. Furthermore, E2F1 could bind CDC25A and positively regulate its expression at the transcriptional level. In addition, CDC25A silencing abolished the effects of E2F1 overexpression on cell proliferation and the cell cycle in NPC. Taken together, the findings of the present study showed that CDC25A silencing attenuated cell proliferation and induced cell cycle arrest in NPC and CDC25A was regulated by E2F1. Hence, CDC25A may be a promising therapeutic target for treatment of NPC.

Low-grade malt lymphoma of the nasopharynx in young adults: Successful treatment of a rare diagnosis at a rare site by radiotherapy.

Mucosa Associated Lymphoid Tissue (MALT) lymphoma is the third most common subgroup of Non-Hodgkin's lymphoma and is the most common type of primary extranodal lymphoma. They are rarely found in the nasopharyngeal region and their mean age at presentation is the sixth decade of life. We present the clinical, pathological, treatment and 5-year follow-up data of 5 cases of nasopharyngeal MALT lymphoma treated with definitive radiotherapy at our hospital, between 2009 and 2011. The average age of diagnosis was 27 years which is more than a decade earlier than what has been reported previously. Clinical symptoms included nasal obstruction, tinnitus and hearing loss. All five patients had locoregional disease. They were treated by definitive radiotherapy to a dose between 30 to 40 Gy. At 5 years of follow-up, 4 patients were in complete remission while one had disease relapse. The younger age of presentation compared to older reports in this rare subsite was an interesting finding in our study. The authors speculate that rising levels of particulate air pollution may have played a part in the etiology in this younger population. Our series shows that despite the younger age, the disease displays an indolent course and responds well to radiotherapy alone as the primary treatment. Recurrence or disseminated disease is also highly treatable with systemic chemotherapy.

Histoplasmosis in nasopharynx clinically mistaken for nasopharyngeal malignancy

Abstract Histoplasmosis is a rare type of fungal infection which may manifest as a respiratory disease or as a disseminated infection. It is common in immunocompromised patients and, in recent times, seen in association with COVID-19. On histopathological examination, many intracellular and extracellular yeast forms are seen, which can be confirmed by fungal stains. Histoplasmosis involving the nasopharyngeal region is quite rare. Till date, only less than 100 cases of pharyngo-laryngeal histoplasmosis have been reported. Such cases are clinico-radiologically easily and frequently mistaken for malignancy. Here, we report a case that initially had COVID-19-like symptoms and later presented with a nasopharyngeal mass clinico-radiologically mistaken as a nasopharyngeal malignancy. The diagnosis was established on histopathological examination and the patient recovered completely with anti-fungal treatment. A high grade of suspicion and thorough histopathological examination, especially in immunocompromised patients, complimented by fungal special stains is quite rewarding as even a disseminated disease is curable.

A Literature Review on Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis and its Complications

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are delayed-type hypersensitivity reactions to medications. Early signs of identification and proper management are critical for patients’ survival. The distinct features initially resemble influenza-like conditions, malaise, and fever with gradual pain and lesions in the oral, ocular, and genital areas along with other systemic symptoms. SJS/TEN can be differentiated: SJS by the degree of skin involvement and TEN by the degree of exfoliation. In SJS, skin involvement is < 10%, whereas in TEN, skin involvement is > 30%; overlapping among the two develops with 10–30% skin involvement. For the identification of culprit drugs, oral provocation tests, patch testing, and in vitro assay tests are used. The estimation of mortality rates for SJS/TEN has been performed by using SCORTEN- severity-of-illness score for toxic epidermal necrolysis. Sulfonamides, anti-epileptics, NSAIDs (oxicams), and allopurinol are some of the medications with a high risk of SJS/TEN development. Drug-mediated SJS/TEN is facilitated by genetic involvement particularly HLA antigens along with CYP450 genetic variants. Most frequent clinical features include mucosal involvement of nasopharyngeal, esophageal, and genital regions accompanying blisters and erosions. A multidisciplinary approach is required for the handling and treatment of SJS/TEN. It is mandatory to withdraw the contributing medicine followed by supportive therapy. Clinical management involves the use of corticosteroids, cyclosporine, and immunoglobulins.

Could the Omicron Variant be the last Variant of Concern of the COVID-19 Pandemic? - Global Immunity is Key

The Omicron variant was designated a Variant of Concern (VoC) due to its increased transmissibility and antibody evasion. Data from several countries however suggested a milder clinical outcome for the Omicron variant compared to the previous VoCs. The clinical outcome in the coming year (2023) is however uncertain due to Omicron’s persistent evolution, developing variants with increased immune escape attributes in the presence of populations that may not possess adequate immunological defences. The Omicron variant utilizes the endosomal route of cell entry unlike previous VoCs. This may be due to Omicron’s superior spike protein receptor binding domain (RBD)’s adhesion to the host cell’s angiotensin converting enzyme II (ACE2) receptor. Efficient cell entry may have increased Omicron’s tropism to rapidly infect the extensive surface area of the nasopharyngeal mucosa and its adjacent sinuses. The endocytic mode of cell invasion may result in a more efficient recruitment of several contemporaneous RBD-ACE2 complexes of the same virus and other viruses to the attached host cell, suggesting a correlation between viralhost cell binding and transmissibility and a negative correlation with clinical severity. The nasopharyngeal region acting as a buffer, would have gained time with the initial containment of the Omicron infection providing immunological protection, preceding significant seeding into the lungs. The combination of previous waves of natural infection, uneven global vaccination efforts and widespread Omicron infection and its most recent sub-variants (BF7 and XXB), may elude worldwide immunity, exacerbating the pathogenic effects of future SARS-CoV-2 outbreaks. Emulating the pattern of waves of infection during the devastating 1918 Spanish influenza, the current COVID-19 Pandemic may have approached an upended immunological equilibrium, due to adverse immunological, anthropogenic and environmental factors, swaying in favour of a more virulent subvariants.

A Dosimetric Comparison of Volumetric-modulated Arc Therapy and IMRT for Cochlea-sparing Radiation Therapy in Locally Advanced Nasopharyngeal Cancer.

Head-and-neck cancer treatment includes radiotherapy as a crucial component. However, radiotherapy, like other treatment modalities, has its own side effects, some of which can be avoided using the latest medical technology and understanding the illness. Despite being a relatively uncommon subtype of head-and-neck cancer, radiation is essential in the treatment of nasopharyngeal carcinoma (NPC). Because of the complex anatomy of the nasopharyngeal region, it is difficult to plan radiotherapy without sparing the cochlea, an important part of the auditory system, and the radiotherapy dosage to it may cause sensorineural hearing loss. In the modern era, volumetric-modulated arc therapy (VMAT) and intensity-modulated radiotherapy (IMRT) have become the gold standard in radiotherapy. With the advancement of these techniques, cochlear sparing is now possible without compromising the tumor dose. We reviewed 14 plans for patients with locally advanced NPC who had received radiation in our department. VMAT plans were created for patients who had IMRT radiotherapy and vice versa. Both approaches were evaluated in terms of cochlea sparing while maintaining the coverage of the planned target volume (PTV). Our study compared the results of two different radiation techniques for locally advanced NPC, IMRT, and VMAT in 14 cases, and we found that VMAT was associated with a lower maximum dose to the cochlea, a lower mean dose to the cochlea, a higher PTV D98% (Gy), a lower PTV D2% (Gy), a higher PTV V95% (%), a lower heterogeneity index, and a higher conformity index. The P value for each comparison was <0.05, which indicates that the difference is statistically significant. These results suggest that VMAT is a better radiation technique than IMRT for locally advanced NPC. VMAT is associated with a lower dose to the cochlea and other organs at risk, which can improve the quality of life and survival of patients. These results suggest that VMAT is a better radiation technique than IMRT for locally advanced NPC. VMAT is associated with a lower dose to the cochlea and other organs at risk, which can improve the quality of life and survival of patients.

TRNA abundance, modification and fragmentation in nasopharyngeal swabs as biomarkers for COVID-19 severity.

Emerging and re-emerging respiratory viruses can spread rapidly and cause pandemics as demonstrated by the recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. The early human immune responses to respiratory viruses are in the nasal cavity and nasopharyngeal regions. Defining biomarkers of disease trajectory at the time of a positive diagnostic test would be an important tool to facilitate decisions such as initiation of antiviral treatment. We hypothesize that nasopharyngeal tRNA profiles could be used to predict Coronavirus Disease 19 (COVID-19) severity. We carried out multiplex small RNA sequencing (MSR-seq) on residual nasopharyngeal swabs to measure simultaneously full-length tRNA abundance, tRNA modifications, and tRNA fragmentation for the human tRNA response to SARS-CoV-2 infection. We identified distinct tRNA signatures associated with mild symptoms versus severe COVID-19 manifestations requiring hospitalization. These results highlight the utility of host tRNA properties as biomarkers for the clinical outcome of SARS-CoV-2.

Reconstruction of nasopharyngeal defect with submental flap during surgery for nasopharyngeal malignant tumors.

To investigate the feasibility and effect of a pedicled submental flap in postoperative defect repair of nasopharyngeal malignant tumors. Eight cases (six women, two men; age, 29-63 years) of postoperative defects after resection of malignant nasopharyngeal tumors with a lesion stage of (r) T1-3N0-2M0 were retrospectively analyzed. Preoperative enhanced thin-slice computed tomography of the neck was performed to predict the submental flap reflux vein. The submental flap was prefabricated during the operation, and the nasopharyngeal mass was removed through the parapharyngeal space approach combined with nasal endoscopy/mandibular external rotation/maxillary overturning. The submental flap was elevated to the nasopharyngeal defect area through the parapharyngeal space for repair. Intraoperative examination confirmed that among the eight submental flaps, three had venous drainage into the internal jugular vein and five had venous drainage into the external jugular vein; these findings were consistent with the preoperative computed tomography findings. The size of the submental flap was 8-10 cm × 5-6 cm. The repair range reached the eustachian orifice on the healthy side and extended to the posterior wall of the maxillary sinus on the affected side. The flap extended to the posterior upper part of the nasal septum at the top, to the oropharynx at the bottom, and to the bony surface of the skull base at the deep side. Primary healing after surgery was achieved, and no flap necrosis occurred. After 3-77 months of follow-up, one patient with recurrent nasopharyngeal carcinoma after radiotherapy developed cervical lymph node recurrence again, one patient with adenoid cystic carcinoma had lung metastasis, and the remaining six patients had no recurrence. The pedicled submental flap is used to repair postoperative defects in the nasopharyngeal region through the cervical parapharyngeal space. It is a simple and fast procedure with adequate tissue volumes. The flap can effectively protect important structures such as the internal carotid artery and reduce the risk of infection and bleeding from postoperative wound exposure.

Mycobiome profiling of nasopharyngeal region of SARS-CoV-2 infected individuals

The present cross-sectional study aims to understand the fungal community composition of the nasopharyngeal region of SARS-CoV-2 infected individuals and how the infection influences the mycobiome therein. The infection significantly (p < 0.05) influenced the alpha diversity. Interestingly, a higher abundance of Cladosporium and Alternaria was noted in the infected individuals and inter-individual variation in mycobiome composition was well supported by beta dispersion analysis (p < 0.05). Moreover, decrease in Aspergillus abundance was observed in infected patients across the four age groups. This study provides insight into the alteration in mycobiome during the viral disease progression and demands continuous investigation to monitor fungal infections.

Omicron Variant of COVID-19: Imaging Pattern on F-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography.

We report a case of omicron infection in a biopsy-proven case of carcinoma breast sent for staging F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) during the omicron COVID wave. FDG PET/computed tomography (CT) revealed increased FDG uptake in nasopharyngeal, oropharynx, and tonsillar regions and bilateral cervical lymph nodes along with uptake in primary carcinoma and locoregional lymph nodes. Based on the clinical history and specific pattern of FDG PET/CT findings (as suggested by SNMMI Taskforce), COVID history and reverse transcription polymerase chain reaction positivity was elicited.

Nasomaxillary Expansion by Endoscopically-Assisted Surgical Expansion (EASE): An airway centric approach

The aim of this study was to analyze the skeletal, dental and airway changes with endoscopically assisted surgical expansion (EASE) to widen the nasomaxillary complex for the treatment of sleep apnea in adults. One hundred and five consecutive patients underwent EASE. Cone beam computed tomography (CBCT) was conducted preoperatively and within four weeks after the completion of the expansion process. Computational fluid dynamic (CFD) analysis was performed on 20 randomly selected patients to assess airway flow changes. One hundred patients (67 males) with the mean age of 35.0±13.5 years (17-64 years) had completed pre- and post-expansion imaging. Ninety-six patients (96%) had successful expansion defined as separation of the midpalatal suture at least 1 mm from anterior nasal spine (ANS) to posterior nasal spine (PNS). The nasal cavity expansion was 3.12±1.11 mm at ANS, 3.64±1.06 mm at first molar and 2.39±1.15 mm at PNS. The zygoma expansion was 2.17±1.11 mm. The ratio of dental expansion to skeletal expansion was 1.23:1 (3.83 mm:3.12 mm) at canine and 1.31:1 (4.77 mm:3.64 mm) at first molar. CFD airway simulation showed a dynamic change following expansion throughout the airway. The mean negative pressure improved in the nasal airway (from -395.5±721.0 to -32.7±19.2 Pa), nasopharyngal airway (from -394.2±719.4 to -33.6±18.5 Pa), oropharyngeal airway (from -405.9±710.8 to -39.4±19.3 Pa) and hypopharyngeal airway (from -422.6±704.9 to -55.1±33.7 Pa). The mean airflow velocity within the nasal airway decreased from 18.8±15.9 to 7.6±2.0 m/s and the oropharyngeal airway decreased from 4.2±2.9 to 3.2±1.2 m/s. The velocity did not change significantly in the nasopharyngeal and hypopharyngeal regions. EASE results in expansion of the midpalatal suture from the ANS to PNS with a nearly pure skeletal movement of minimal dental effect. The expansion of the nasomaxillary complex resulted in the widening of the nasal sidewall throughout the nasal cavity. The improved air flow dynamics was demonstrated by CFD simulation.

Immunocytochemical Assessment of ACE2 and TMPRSS2 in Nasopharyngeal Swabs from SARS-CoV-2 Patients.

SARS-CoV-2 is a positive-sense single-stranded RNA virus. It is enveloped by four structural proteins. The entry of the virus into the host cells is mediated by spike protein binding to the angiotensin converting enzyme 2 (ACE2) and proteolytic cleavage by transmembrane protease serine 2 (TMPRSS2). In this study, we analyzed the expression of the ACE2 receptor and TMPRSS2 in cases under investigation for SARS-CoV-2 infection. The study was carried out using the viral transport medium of consecutive nasopharyngeal swabs from 300 people under examination for SARS-CoV-2 infection. All samples underwent the SARS-CoV-2 transcriptase-mediated amplification assay (Procleix® SARS-CoV-2) to detect the virus. Immunocytochemistry was used in each sample to detect the presence of the SARS-CoV-2 nucleoprotein, the ACE2 receptor, and TMPRSS2. An immunocytochemical study with monoclonal antibody against SARS-CoV-2 viral nucleoprotein showed positivity in squamous cells. ACE2 were not detected in the squamous cells obtained from the nasopharyngeal samples. SARS-CoV-2 predominantly localizes to squamous cells in cytology samples of patients with positive transcriptase-mediated amplification SARS-CoV-2 assay results. The immunocytochemical negativity for ACE2 evidenced in the present study could be related to the cellular heterogeneity present in the nasopharyngeal smear samples and could be related to variations at the genomic level. Our results suggest that SARS-CoV-2 might be present in the nasopharyngeal region because viral cell junctions are weaker. This facilitates viral concentration, infective capacity and migration to specific organs, where SARS-CoV-2 infects target cells by binding to their receptors and then entering.

How to rinse the nasal cavities?

Aim: Development of an effective method of rinsing the nasal cavities and paranasal sinuses using the Zatoxin Rinse kit. Material and methods: In order to develop recommendations for rinsing the nasal cavities, a cadaver head specimen from Poznań Lab was used. The nasal cavities were rinsed with a methylene blue solution - 0.8 ml of 10% methylene blue in 240 ml of water. Rinsing was performed in the standard recommended position - the head tilted slightly forward (approx. 20–30 degrees) and to the side – approx. 45 degrees. After endoscopic examination, endoscopic surgery of the paranasal sinuses was performed and the staining of the mucosa of the paranasal sinuses was assessed. The nasal cavities were rinsed again with a solution of water and methylene blue in the head position as described above. Endoscopic examination was performed with the assessment of the staining of the nasal mucosa and paranasal sinuses, and the rinsing was repeated with the head tilted forward to 60 degrees and laterally to 45 degrees. The staining of the mucosa was recorded during the endoscopic examination. Results: The nasal rinsing performed allowed the fluid to flow along the turbinates into the nasopharyngeal region and then out. After opening the paranasal sinuses, it turned out that only a small amount of methylene blue had penetrated into the maxillary sinuses; There was also no staining of the mucosa within the ethmoid cells, the frontal sinus or the sphenoid sinus. Rinsing the nasal cavities again in the same position, but after the ethmoidectomy, showed poor penetration of methylene blue into the ethmoid region, the frontal sinus ostium and the sphenoid sinus ostium. The re-rinsing of the nasal cavities with the head tilted forward by at least 60 degrees and to the side by 45 degrees resulted in a stronger staining of the rush top and the staining of the entrance to the frontal sinus with methylene blue. Conclusions: The way the head is positioned when using Zatoxin Rinse should be adapted to the disease, and in the case of surgical treatment, to the type of surgery performed and to which sinuses are affected by the disease, so that the solution reaches the required regions.

Study on Hydroxychloroquinine Sulfate Being Given to the Admitted COVID -19 Positive Patients at Institute of JLNMCH, Bhagalpur, Bihar, India.

BackgroundAs the global death toll from new coronavirus illness (COVID-19) rises, the scientific community and healthcare systems are under massive pressure to manage the outbreak and develop effective medical remedies. Meanwhile, desperation has pushed practitioners, scientists, and authorities to recommend and attempt medicines with little or no proof. Despite the lack of clear and unequivocal facts supporting its efficacy and safety, hydroxychloroquine-sulfate (HCQS) has recently received substantial public and political interest in treating and prophylaxis new infectious diseases COVID-19.AimTo analyze the impact of HCQS in COVID-19-positive patients admitted at tertiary level government-owned Jawaharlal Nehru Medical College and Hospital (JLNMCH, Bhagalpur) Bihar.MethodsTwo hundred two RT-PCR-positive COVID-19 patients were included in this research. The study participants were randomly distributed into the intervention category and control category, each consisting of 101 study subjects. Study participants in the intervention category were administered hydroxychloroquine in 200 mg tablets. The control category was given placebo tablets that looked similar to tablets of hydroxychloroquine and were given in the same pattern. Chest X-ray PA view, 12 lead ECG, baseline hemogram including a concentration of CD4 cells, ratio between the concentration of CD8 cells and CD4 cells and concentration of CD8 cells, the concentration of C-reactive protein, RT PCR test of samples obtained from the oropharyngeal region and nasopharyngeal region nasopharyngeal for verification COVID-19 were done. These measurements were carried out in both the control and intervention categories at baseline and at the moment of obtaining a negative RT-PCR report.ResultsThe confirmed cases of COVID-19 was 52.9% in the intervention category and 53.4% in the control category at the end of the administration of drugs. Symptoms related to COVID-19 were observed in 11.6% of subjects in the intervention category and 13.5% in the control category. Other new symptoms were observed in 16.8% of subjects in the intervention category and 14.5% of study subjects in the control category. One death was reported in the control category. Emergency hospitalization was required for one subject in the intervention category, while two subjects in the control category required emergency hospitalization. 12.4 days was the mean duration of recovery in the intervention category, while 13.6 days were the mean duration of recovery in the control category. The recovery duration and COVID-related symptoms were lesser in the intervention category than in the control category; however, the variation between the two categories was statistically non-significant (p˃0.01).ConclusionAccording to this research, no statistically significant difference was noticed in COVID-19 incidence between the control category and intervention category, showing that hydroxychloroquine sulfate cannot be utilized as the main curative agent in the treatment of COVID-19. However, there was a reduction in recovery days and symptoms related to COVID-19 in study subjects administered with HCQS.

Reduction in SARS-CoV-2 Oral Viral Load with Prophylactic Mouth Rinse

Abstract Objectives The medical and health facilities are at high risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study tested the preprocedural prophylactic mouthwash rinses to reduce the oral viral load. The findings from this study will help the practitioners to select the best mouthwash for the patients to mitigate the risk of transmission during aerosolizing. This study aimed to evaluate the effectiveness of four commonly used types of mouthwash in reducing intraoral viral load among hospitalized coronavirus disease 2019 patients. Materials and Methods This prospective cohort study was conducted with 116 patients referred to the Masih Daneshvari Hospital in Tehran, Hamadan University of Medical Sciences of Hamadan City, and Mashhad University of Medical Sciences. Patients were randomized into four groups with each group rinsed their mouth with 20 mL of 2% povidone-iodine, 1% hydrogen peroxide, normal saline as a control study group, or 0.12% chlorhexidine, respectively, for 20 seconds. The standard reverse transcription polymerase chain reaction method evaluated the virus load before and at 1 hour, 2 hours, and 4 hours after using the mentioned mouthwash. Results Our results revealed that chlorhexidine and H2O2 showed the highest efficiency in reducing SARS-Co-2 load in the oral cavity and nasopharyngeal region of patients; they increased the Ct values by 9 to 10 (before: 25.84 vs. after 32. 4, p &lt; 0.455) (17.333 vs. after 26.497, p &lt;0.097). Conclusion Our findings suggest that chlorhexidine and H2O2 could be used in dental clinics to reduce the risk of transmitting the SARS-CoV-2 virus from infected individuals to dentists before dental procedures.

Risk factors for bleeding complications during venovenous extracorporeal membrane oxygenation as a bridge to recovery.

BackgroundBleeding complications during venovenous extracorporeal membrane oxygenation (V‐V ECMO) can be critical. However, there is limited information on the associated risk factors. This study investigated the risk factors for bleeding complications during V‐V ECMO as a bridge to recovery.MethodsThis single‐center retrospective study enrolled 59 patients (bleeding and non‐bleeding groups) who received V‐V ECMO from 2012 to 2020, to evaluate whether peak activated partial thromboplastin time (APTT) value, lowest platelet count, and mobilization to sitting on the edge of the bed during V‐V ECMO were risk factors for bleeding complications, defined according to the Extracorporeal Life Support Organization guidelines. Age, sex, body mass index, Sequential Organ Failure Assessment score, and ECMO duration before bleeding complications were covariates in the multivariate logistic regression analysis.ResultsThirty‐one (53%) participants experienced 36 bleeding complications; the ECMO cannulation site, gastrointestinal tract, and nasopharyngeal region were the most common bleeding sites. The use of transfusion products and length of ECMO and intensive care unit stay were significantly and medical costs were non‐significantly increased in the bleeding group. Peak APTT (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01–1.05, p < 0.01) was significantly associated whereas the lowest platelet count (OR 0.96, 95% CI 0.82–1.13, p = 0.66) was unassociated with bleeding complications during ECMO. Achieving mobilization (OR 0.14, 95% CI 0.02–1.17, p = 0.07) decreased the trend of risk for bleeding complications.ConclusionsPeak APTT might be an independent modifiable factor for bleeding complications during V‐V ECMO. The protective effect of mobilization during V‐V ECMO requires further investigation.

Fluorescence-enabled evaluation of nasal tract deposition and coverage of pharmaceutical formulations in a silicone nasal cast using an innovative spray device

IntroductionThe characterisation of nasal formulations is a critical point. However, there are still no recommendations or guidelines in terms of standard approaches for evaluating the formulation's nasal deposition and/or coverage profile. This study optimises a method for quantifying silicone nasal cast deposition and coverage of liquid formulations using different nasal devices. ObjectivesThe present work investigates the nasal deposition and coverage patterns of innovative nasal spray nozzles producing slow velocity soft mists, using a nasal cavity replica and a fluorescent dye. MethodsThe study of the deposition pattern of a fluorescent liquid formulation in a transparent nasal cast was carried out in both the presence and absence of a simulated inhalation flow. The extent of the deposition pattern was investigated using ImageJ and fluorescence in the nasal cast, quantified by fluorometric analysis. The particle size distribution and initial droplet velocity were determined using a laser diffractometer and a high-speed camera with a frame rate of 1000 fps. ResultsA uniform intranasal coverage was obtained with droplets of a volume median particle size (Dv50) between 15 and 25 µm in airflow between 10 and 30 L/min. In these conditions, aerosol formulations can be uniformly deposited in the vestibule and turbinate cavity nasal regions, with less than 10 % passing beyond the nasopharyngeal region. ConclusionThe method applied allowed for the determination of the coverage of the nasal cast in different regions using images analysis and fluorometric analysis. Droplet velocity is a critical parameter in the deposition in the nasal cavity. With standard swirl nozzles, many droplets are found on the surface of the nasal vestibule. Soft mist nozzles produce smaller droplets at a much lower initial velocity (<1 m/s), resulting in a more uniform coverage.

Determining the frequency of Streptococcus pneumoniae carriers and its microbial resistance in children.

Streptococcus pneumoniae is a common cause of bacterial infections of the respiratory system, middle ear infection, bacteremia, meningitis, and pneumonia, especially in children. Due to the lack of information about the frequency and resistance of Streptococcus pneumoniae to antibiotics, the present study was performed to determine the frequency of carriers of Streptococcus pneumoniae and its microbial resistance in children. For this purpose, the current descriptive cross-sectional study was conducted from November to March 2020 on 554 children aged 2-12 years in kindergartens and schools. This study collected samples with a sterile swab from the nasopharyngeal region, transported them to the laboratory by a transport medium, and then cultured them on an agar culture medium. After isolation, confirmatory tests and antibiotic susceptibility were performed. The results were analyzed using SPSS16 software and interpreted according to Mann Whitney U and Chi-Square Tests. Streptococcus pneumoniaewas found in 15% of samples, and the antibiotic resistance of the isolates to the antibiotics azithromycin, amoxicillin, rifampicin, amoxicillin-clavulanic acid, trimethoprim/Sulfamethoxazole, and ceftriaxone were 63.9%, 56.6%, 41%, 37.3%, 37.3%, and 3.6%, respectively. Also, 31.1% of the isolates were not resistant to any antibiotics. According to the results, excessive use of antibiotics has led to high resistance to azithromycin, amoxicillin, amoxicillin/clavulanic acid, and trimethoprim/Sulfamethoxazole, which indicates an increased risk of refractory infectious diseases. For this reason, it is necessary to adequately educate physicians and the general public about the overuse of antibiotics.

Diagnostic Accuracy of 18F‐FDG‐PET/CT and 18F‐FDG‐PET/MRI in Detecting Locoregional Recurrence of HNSCC 12 Weeks after the End of Chemoradiotherapy: Single‐Center Experience with PET/MRI

Purpose In head and neck squamous cell carcinoma (HNSCC), the early diagnosis and efficient detection of recurrences and/or residual tumor after treatment play a very important role in patient's prognosis. Positron emission tomography (PET) using 2-deoxy-2-18F-fluoro-D-glucose (18F-FDG) has become an established method for the diagnosis of suspected recurrence in head and neck carcinomas. In particular, integrated PET/MRI imaging that provides optimal soft tissue contrast and less dental implant artifacts compared to PET/CT is an intriguing technique for the follow-up imaging of HNSCC patients. The aim of this study was to evaluate the benefit of PET/MRI compared to PET/CT in post-treatment follow-up imaging of HNSCC patients. Methods This retrospective observational cohort study consists of 104 patients from our center with histologically confirmed HNSCC. All patients received chemoradiotherapy (CRT) and underwent 18F-FDG-PET/CT (n = 52) or 18F-FDG-PET/MRI (n = 52) scan 12 weeks after the end of treatment. Image analysis was performed by two independent readers according to a five-point Likert scale analysis. Results PET/MRI was more sensitive (1.00 vs. 0.77) than PET/CT in the detection of locoregional recurrence. PET/MRI also had better negative (1.00 vs. 0.87) predictive values. AUCs for PET/MRI and PET/CT on patient-based analysis were 0.997 (95% CI 0.989–1.000) and 0.890 (95% CI 0.806–0.974), respectively. The comparison of sensitivity, AUCs, and negative predictive values revealed a statistically significant difference, p < 0.05. In PET/CT, false-negative and positive findings were observed in the more advanced disease stages, where PET/MRI performed better. Also, false-negative findings were located in the oropharyngeal, laryngeal, and nasopharyngeal regions, where PET/MRI made no false-negative interpretations. Conclusion Based on these results, PET/MRI might be considered the modality of choice in detecting locoregional recurrence in HNSCC patients, especially in the more advanced stages in the oral cavity, larynx, or nasopharynx.