The morphometrical evaluation after uvulopalatopharyngoplasty.

OBJECTIVES: The aim of this study was to evaluate the efficacy of uvulopalatopharyngoplasty (UPPP) and the corresponding postoperative morphometrical changes. METHODS: Patients diagnosed with obstructive sleep apnea syndrome who complained of snoring and apnea were enrolled in this study. Pre- and postoperative tests, including CTs, pharyngeal volume (PV), cross-sectional area (CSA), and six-category morphometrical studies, were performed. RESULTS: Of 11 patients included, 10 showed improvement of symptoms. BMI correlated with the respiratory event index (REI). In terms of PV, there was a significantly wider postoperative area. The rate of change between preoperative REI and postoperative REI (ΔREI) correlated with the amount of change of PV between preoperative PV and postoperative PV (ΔPV). CSA increased postoperatively and correlated with REI. Uvula space (UV) and distance between the hyoid bone and the base of the tongue (HB) increased postoperatively, and posterior airway space (PAS) and epiglottic space (Epi) decreased postoperatively. UV and PAS were significant (p = 0.046, 0.014). UV was related to REI. CONCLUSION: Widening the PV, increasing CSA, and the posterior movement of the tongue base after UPPP surgery were found. The improvement of REI did not depend only on volume. These results suggest that it was important not only to widen the PV but also to improve the shape of the pharynx.

Effects of jaw movement in bimaxillary orthognathic surgery on the upper airway: Computational fluid dynamics analysis.

Maxillomandibular repositioning in orthognathic surgeries has both morphologic and functional effects. These surgeries are thought to change the pharyngeal space and cause obstructive sleep apnoea syndrome, however. The primary purpose of this study is to evaluate the effects of jaw movement in bimaxillary orthognathic surgery on airway function and to identify the morphometric factors that can predict postoperative airway function. The subjects were 11 males and 12 females who had undergone orthognathic surgeries of the maxilla and mandible. The results of cephalometric analysis, cross-sectional area of the pharynx (CSA), pharyngeal volume and computational fluid dynamics (CFD) were compared. The CSA of the nasal (CSA1), total volume and total nasal volume decreased after surgery with statistical significance. Velocity at the oropharyngeal space (V2) increased after surgery with statistical significance. V2, CSA of the oropharyngeal space (CSA2) and PV were correlated with the horizontal posterior movement of point B, point Menton and overjet. V2 and CSA2 were correlated with SNB before and after surgery in all 46 analyses. Changes in pharyngeal airflow were more affected by pressure drop in the pharyngeal space (ΔPp) than by pressure drop in the nasal space (ΔPn). The relationship between the actual amount of change in the cephalometric reference point and the airway function is evident. CFD may thus be very useful as morphological analysis in preoperative treatment decision making.

A New Method to Detect Variants of SARS-CoV-2 Using Reverse Transcription Loop-Mediated Isothermal Amplification Combined with a Bioluminescent Assay in Real Time (RT-LAMP-BART).

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), of which there are several variants. The three major variants (Alpha, Delta, and Omicron) carry the N501Y, L452R, and Q493R/Q498R mutations, respectively, in the S gene. Control of COVID-19 requires rapid and reliable detection of not only SARS-CoV-2 but also its variants. We previously developed a reverse transcription loop-mediated isothermal amplification assay combined with a bioluminescent assay in real time (RT-LAMP-BART) to detect the L452R mutation in the SARS-CoV-2 spike protein. In this study, we established LAMP primers and peptide nucleic acid probes to detect N501Y and Q493R/Q498R. The LAMP primer sets and PNA probes were designed for the N501Y and Q493R/Q498R mutations on the S gene of SARS-CoV-2. The specificities of RT-LAMP-BART assays were evaluated using five viral and four bacterial reference strains. The sensitivities of RT-LAMP-BART assays were evaluated using synthetic RNAs that included the target sequences, together with RNA-spiked clinical nasopharyngeal and salivary specimens. The results were compared with those of conventional real-time reverse transcription-polymerase chain reaction (RT-PCR) methods. The method correctly identified N501Y and Q493R/Q498R. Within 30 min, the RT-LAMP-BART assays detected up to 100-200 copies of the target genes; conventional real-time RT-PCR required 130 min and detected up to 500-3000 copies. Surprisingly, the real-time RT-PCR for N501Y did not detect the BA.1 and BA.2 variants (Omicron) that exhibited the N501Y mutation. The novel RT-LAMP-BART assay is highly specific and more sensitive than conventional real-time RT-PCR. The new assay is simple, inexpensive, and rapid; thus, it can be useful in efforts to identify SARS-CoV-2 variants of concern.

Characteristics predicting laparoscopic skill in medical students: nine years' experience in a single center.

INTRODUCTION: We introduced laparoscopic simulator training for medical students in 2007. This study was designed to identify factors that predict the laparoscopic skill of medical students, to identify intergenerational differences in abilities, and to estimate the variability of results in each training group. Our ultimate goal was to determine the optimal educational program for teaching laparoscopic surgery to medical students. METHODS: Between 2007 and 2015, a total of 270 fifth-year medical students were enrolled in this observational study. Before training, the participants were asked questions about their interest in laparoscopic surgery, experience with playing video games, confidence about driving, and manual dexterity. After the training, aspects of their competence (execution time, instrument path length, and economy of instrument movement) were assessed. RESULTS: Multiple regression analysis identified significant effects of manual dexterity, gender, and confidence about driving on the results of the training. The training results have significantly improved over recent years. The variability among the results in each training group was relatively small. CONCLUSIONS: We identified the characteristics of medical students with excellent laparoscopic skills. We observed educational benefits from interactions between medical students within each training group. Our study suggests that selection and grouping are important to the success of modern programs designed to train medical students in laparoscopic surgery.

Efficacy of Vonoprazan for Proton Pump Inhibitor-Resistant Reflux Esophagitis.

BACKGROUND: Vonoprazan (VPZ) is a novel potassium-competitive acid blocker that may be clinically beneficial for proton pump inhibitor (PPI)-resistant reflux esophagitis (RE). The aim of this study was to investigate the efficacies of VPZ therapy at 20 mg for 4 weeks in patients with PPI-resistant RE and VPZ maintenance therapy at 10 mg for 8 weeks in patients who have been successfully treated. METHODS: Subjects comprised 24 patients with PPI-resistant RE (Los Angeles classification grade A/B/C/D: 3/7/11/3). After confirming PPI-resistant RE by endoscopy, 20 mg VPZ was administered. Endoscopy was performed 4 weeks after the initiation of VPZ. Symptoms were evaluated using the frequency scale for the symptoms of gastroesophageal reflux disease (FSSG). Maintenance therapy with 10 mg VPZ was performed and endoscopy was conducted after 8 weeks. RESULTS: In 21 (87.5%) out of 24 patients, esophageal mucosal breaks were successfully treated by 20 mg VPZ. The median FSSG score was significantly lower on days 1-7, 14, and 28 after the initiation of VPZ than before its administration. Maintenance therapy with 10 mg VPZ prevented the relapse of esophageal mucosal breaks in 16 (76.2%) out of 21 patients. CONCLUSION: VPZ was effective for most patients with PPI-resistant RE.

Pathogenesis of Double-Dose Proton Pump Inhibitor-Resistant Non-Erosive Reflux Disease, and Mechanism of Reflux Symptoms and Gastric Acid Secretion-Suppressive Effect in the Presence or Absence of Helicobacter pylori Infection.

BACKGROUND: Various mechanisms have been suggested to be responsible for contributing to the occurrence of proton pump inhibitor (PPI)-resistant non-erosive reflux disease (NERD). The aims of this study were to clarify the pathogenesis of PPI-resistant NERD. METHODS: Fifty-three patients with NERD, who had persistent reflux symptoms despite taking double-dose PPI, were included in this study. After excluding eosinophilic esophagitis (EoE) and primary esophageal motility disorder, esophageal impedance-pH monitoring was carried out. In symptom index (SI)-positive patients, the mechanism of SI positivity and the percent time with intragastric pH >4 were investigated according to the presence or absence of Helicobacter pylori infection. RESULTS: One of the 53 patients had EoE, and 4 had primary esophageal motility disorder. Twenty-three and 2 patients were SI-positive for liquid and gas-only reflux respectively. Of 17 SI-positive, H. pylori-negative patients, 5 were SI-positive for acid reflux, whereas all of the H. pylori-positive patients were SI-positive for non-acid reflux. The percent time with intragastric pH >4 was significantly lower in the H. pylori-negative patients than in the H. pylori-positive patients. CONCLUSIONS: The pathogenesis of double-dose PPI-resistant NERD was identified in 57%. In some of H. pylori-negative patients, acid-related symptoms were observed. However, in H. pylori-positive patients, these symptoms were excluded by taking double-dose PPI.

Assessment of the incidence of chronic pain and discomfort after primary inguinal hernia repair.

BACKGROUND: Chronic pain and discomfort is a notable complication after inguinal hernia repair. This study assesses the incidence and degree of chronic pain and discomfort after primary inguinal hernia repair performed in our hospital and aims to clarify its relationship to the type of mesh placement. MATERIALS AND METHODS: A retrospective analysis was conducted of 334 patients (378 lesions) who underwent primary inguinal hernia using the Lichtenstein (onlay mesh), Ultrapro Plug (UPP; onlay plus plug mesh), modified Kugel Patch (onlay and underlay mesh), or laparoscopic transabdominal preperitoneal (TAPP; underlay mesh) procedure. Postoperative pain was assessed using a numerical rating scale at postoperative 2-3 wk, 3 mo, and 6 mo. Postoperative discomfort was assessed 6 mo afterward. RESULTS: Questionnaire responses were received for 378 lesions (100%) after 2-3 wk, 229 (60.6%) after 3 mo, and 249 (65.9%) after 6 mo. The majority of chronic pain experienced was mild, and no patient suffered from severe pain. The level of pain tended to be less for the TAPP procedure than for other methods. Discomfort at rest was significantly less for TAPP versus Ultrapro Plug (P < 0.01), and discomfort with movement was significantly less for TAPP versus modified Kugel (P < 0.05). CONCLUSIONS: Onlay mesh appears to be a risk factor in chronic pain and discomfort. The lower level of chronic pain and discomfort with underlay mesh placement is considered to result from the reduced risk of nerve damage in this procedure than in the onlay mesh placement procedure.

Thoracoscopic long myotomy in the prone position to treat rapid esophageal contractions with normal latency.

A 56-year-old woman with an 8-year history of dysphagia and chest pain received a diagnosis of diffuse esophageal spasm by esophageal high-resolution manometry (HRM). Approximately 2 years of medical therapy was ineffective, and the patient's symptoms were worsening. Therefore, surgery was considered to be the most optimal treatment for this patient. The right thoracoscopic approach was selected because a long myotomy from the distal to proximal level of the esophagus was needed based on the HRM findings. The operation was performed in the prone position with establishment of pneumothorax. The total length of the myotomy was 16 cm, and the operation was finished within 2 hours. After the operation, the symptoms were considerably improved and no contractions were detected by HRM. The HRM findings before the operation were classified as rapid contractions with normal latency based on the 2012 Chicago classification of esophageal motility. Treatment for patients with rapid esophageal contractions with normal latency has not been previously described; however, treatment for diffuse esophageal spasm was considered to be pertinent to this patient. In conclusion, right thoracoscopic esophageal long myotomy in the prone position with establishment of pneumothorax may be useful when a proximal-level esophagomyotomy is required based on preoperative mapping by HRM.

Effects of nasal septum perforation repair surgery on three-dimensional airflow: an evaluation using computational fluid dynamics.

The purpose of this research is to determine the cause of nasal perforation symptoms and to predict post-operative function after nasal perforation repair surgery. A realistic three-dimensional (3D) model of the nose with a septal perforation was reconstructed using a computed tomography (CT) scan from a patient with nasal septal defect. The numerical simulation was carried out using ANSYS CFX V13.0. Pre- and post-operative models were compared by their velocity, pressure gradient (PG), wall shear (WS), shear strain rate (SSR) and turbulence kinetic energy in three plains. In the post-operative state, the crossflows had disappeared, and stream lines bound to the olfactory cleft area had appeared. After surgery, almost all of high-shear stress areas were disappeared comparing pre-operative model. In conclusion, the effects of surgery to correct nasal septal perforation were evaluated using a three-dimensional airflow evaluation. Following the surgery, crossflows disappeared, and WS, PG and SSR rate were decreased. A high WS.PG and SSR were suspected as causes of nasal perforation symptoms.

[Clinicopathological characteristics and generational changes in metachronous gastric cancer of the reconstructed gastric tube].

This study investigated gastric tube cancer (GTC) to clarify the clinicopathological characteristics in different generations. We analyzed 165 cases with metachronous GTC; 9 cases from our institution and 156 from reported Japanese cases. Cases were divided into 3 groups to provide a detailed analysis of age-specific variations. GTC most commonly occurred in the lower gastric tube, and the most common histological type was tubular adenocarcinoma (70%). There were no age-related variations in the site and histological type of GTC. The incidence rate of endoscopic detection increased from 2003 to 74% in 2012, and the incidence of early GTC detection also significantly increased in this period. The rate of endoscopic treatment before 2003 was approximately 20%, and it doubled over the 10-year course of the study. The recent progress made in the diagnosis and treatment of GTC may have contributed to an improvement in its prognosis.

SnoN/SKIL modulates proliferation through control of hsa-miR-720 transcription in esophageal cancer cells.

It is now evident that changes in microRNA are involved in cancer progression, but the mechanisms of transcriptional regulation of miRNAs remain unknown. Ski-related novel gene (SnoN/SKIL), a transcription co-factor, acts as a potential key regulator within a complex network of p53 transcriptional repressors. SnoN has pro- and anti-oncogenic functions in the regulation of cell proliferation, senescence, apoptosis, and differentiation. We characterized the roles of SnoN in miRNA transcriptional regulation and its effects on cell proliferation using esophageal squamous cell carcinoma (ESCC) cells. Silencing of SnoN altered a set of miRNA expression profiles in TE-1cells, and the expression levels of miR-720, miR-1274A, and miR-1274B were modulated by SnoN. The expression of these miRNAs resulted in changes to the target protein p63 and a disintegrin and metalloproteinase domain 9 (ADAM9). Furthermore, silencing of SnoN significantly upregulated cell proliferation in TE-1 cells, indicating a potential anti-oncogenic function. These results support our observation that cancer tissues have lower expression levels of SnoN, miR-720, and miR-1274A compared to adjacent normal tissues from ESCC patients. These data demonstrate a novel mechanism of miRNA regulation, leading to changes in cell proliferation.

Primary intraosseous squamous cell carcinoma of the jaw: two new cases and review of the literature.

BACKGROUND: Primary intraosseous squamous cell carcinoma is very rare. We report two cases of primary intraosseous squamous cell carcinoma of the jaw, one arising from an odontogenic cyst and the other arising de novo. METHODS AND RESULTS: The first case was a 76-year-old man with right mandible pain. A panoramic radiography and computed tomography revealed a large mandibular radiolucency. A biopsy revealed squamous cell carcinoma, and radiotherapy and hemimandibulectomy were performed. The second case was a 50-year-old man with lymph node swelling on the left neck. Squamous cell carcinoma of the lymph node was suspected after fine needle biopsy. After left neck dissection, histological testing of the odontogenic cyst revealed squamous cell carcinoma, of which the mandible was thought to be the primary site. CONCLUSION: Our two cases have no recurrence, and panoramic radiography was a useful tool in the detection of mandible disease.

Laparoscopic Repair Using Self-Fixating Mesh in an Adult Patient with a Sciatic Hernia and Irreducible Small Bowel: A Case Report and Literature Review.

Sciatic hernia is a rare type of pelvic floor hernia. The herniated tissue can include the ureter, small and large bowel, and ovary, among other tissues. Only a few cases of laparoscopic treatment for a sciatic hernia with small-bowel incarceration have been reported. We report our experience using a laparoscopic approach for treatment of sciatic hernia in an 83-year-old woman and review the literature on sciatic hernias. The patient was referred to our hospital complaining of constipation and abdominal bloating. Computed tomography (CT) scanning showed a right sciatic hernia containing the small bowel. Laparoscopic repair of the sciatic hernia was performed using a self-fixating mesh. The patient was discharged after an uneventful postoperative course and has not developed abdominal bloating or constipation postoperatively. In conclusion, a sciatic hernia was successfully repaired using a laparoscopic trans-preperitoneal approach and ProGrip Self-Fixating Mesh.

Prosthetic repair of an incarcerated groin hernia with small intestinal resection.

PURPOSE: No consensus has been reached on the use of prostheses in a potentially infected operating field. In this study, we evaluated the validity of a mesh prosthesis for the repair of incarcerated groin hernias with intestinal resection. METHODS: Twenty-seven patients underwent operations for correction of incarcerated groin hernias with small intestinal resection at our hospital between January 2000 and March 2010. The patients were divided into two groups: those who underwent repair with a prosthetic mesh and those who underwent primary hernia repair. Patients with intestinal perforations, abscess formations, panperitonitis, and those who required colon resections were excluded. The length of the operation, blood loss, and incidences of surgical site infection, postoperative ileus, and recurrence were evaluated in each group. RESULTS: Of the 27 patients studied, 10 (37%) underwent tension-free repair with a mesh, and 17 (63%) underwent primary hernia repair. Although the patients who underwent primary hernia repair were significantly older than the patients who underwent mesh repair (P = 0.015), no statistically significant differences in morbidity, including surgical site infection, or mortality, were identified. CONCLUSION: Strangulated inguinal hernias cannot be considered a contraindication to the use of a prosthetic mesh even in cases requiring small-intestinal resection.

A case of rapid diagnosis of Boerhaave syndrome by thoracic drainage.

BACKGROUND: Boerhaave syndrome is a rare and often fatal syndrome. Delayed diagnosis and treatment is closely associated with prolonged morbidity and increased mortality. In general, esophagography is usually chosen as the diagnostic procedure, but it has a relatively high false-negative rate. There are no reports, to our knowledge, regarding the efficacy of thoracic drainage, although it is easier to perform and more immediate than esophagography in the emergency department. OBJECTIVES: To report the efficacy of thoracic drainage for rapid diagnosis and treatment of Boerhaave syndrome. CASE REPORT: An 80-year-old woman was admitted with vomiting and sudden onset of postprandial chest pain radiating to the back. Initially, myocardial infarction or aortic dissection was suspected, but was excluded by point-of-care tests and computed tomography (CT) scan, which revealed a left-sided pneumothorax, heterogeneous left pleural effusion, and pneumomediastinum at the lower level of the esophagus. Boerhaave syndrome was suspected and confirmed by thoracic drainage, which drained off bloody fluid and residual food such as broccoli. Emergency thoracotomy was performed within 4 h after onset of symptoms. The patient made an uneventful recovery. CONCLUSION: Findings in this case indicate that chest pain, left-sided massive effusion on chest radiography, and left-sided massive heterogeneous effusion on CT scan are important for the diagnosis of Boerhaave syndrome. Subsequent thoracic drainage is useful for confirming Boerhaave syndrome, and such a strategy might lead to a good prognosis for patients with this rare but critical disease.

New Modified Transoral Approach to Remove a Hilar Stone of the Submandibular Gland: A Case Report.

Nerve damage and intraoperative bleeding for the removal of the hilar stones are possible. We used the new modified lateral oral floor approach with a 2-3 cm longitudinal mucosal incision outside of the Wharton's. There were no complications and our technique seemed to be effective.

Postoperative functional evaluation of obstructive sleep apnea syndrome by computational fluid dynamics.

The aim of this study is to evaluate the efficacy of uvulopalatopharyngoplasty and the corresponding postoperative airflow. Eleven patients diagnosed with obstructive sleep apnea syndrome who complained of snoring and apnea were enrolled in this study. Computational fluid dynamics (CFD) was implemented. CFD could be accomplished in nine cases. Airflow analysis was not possible in cases with a high respiratory event index (REI) score. Before surgery, stenosis was identified in the oropharynx and epiglottic area. And the airflow velocity and pressure were found to have significantly decreased in the oropharynx postoperatively, while in the epiglottic area, those data had increased postoperatively in some cases. The velocity and pressure of the oropharynx are related to REI score. From the CFD analysis, airflow analysis is important for evaluating the apnea state. It is suggested that the postoperative function can now be predicted preoperatively.

Impact of Second-line Chemotherapy on Prognosis: Response of Advanced Gastric Cancer to Taxanes Plus Ramucirumab.

BACKGROUND/AIM: The impact of clinical response to taxanes plus ramucirumab (RAM) on overall survival (OS) has not been clarified for advanced gastric cancer (AGC), although this type of therapy is already in use as second-line chemotherapy (CTx). This study aimed to investigate the prognostic impact of the clinical response to taxanes plus ramucirumab (RAM) for AGC patients. PATIENTS AND METHODS: This study included AGC patients treated with paclitaxel (PTX) or nab-paclitaxel (nab-PTX) and RAM. A retrospective analysis of response and survival rates in consecutive medical records of patients was performed. RESULTS: Forty-two patients were enrolled. Median progression-free survival and OS were 5.4 months [95% confidence interval (CI)=4.440-6.361] and 11.8 months (95% CI=8.648-15.019), respectively. In Cox-hazard multivariate analysis, peritoneal metastasis [hazard ratio (HR)=2.830; 95% CI=1.320-6.067; p=0.008], and disease control rate (HR=0.310; 95% CI=0.129-0.741; p=0.008) were independent factors. CONCLUSION: The response to taxanes plus RAM CTx had an impact on the survival of patients with AGC.

Detection of SARS-CoV-2 and the L452R spike mutation using reverse transcription loop-mediated isothermal amplification plus bioluminescent assay in real-time (RT-LAMP-BART).

The new coronavirus infection (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be fatal, and several variants of SARS-CoV-2 with mutations of the receptor-binding domain (RBD) have increased avidity for human cell receptors. A single missense mutation of U to G at nucleotide position 1355 (U1355G) in the spike (S) gene changes leucine to arginine (L452R) in the spike protein. This mutation has been observed in the India and California strains (B.1.617 and B.1.427/B.1.429, respectively). Control of COVID-19 requires rapid and reliable detection of SARS-CoV-2. Therefore, we established a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay plus a bioluminescent assay in real-time (BART) to detect SARS-CoV-2 and the L452R spike mutation. The specificity and sensitivity of the RT-LAMP-BART assay was evaluated using synthetic RNAs including target sequences and RNA-spiked clinical nasopharyngeal and saliva specimens as well as reference strains representing five viral and four bacterial pathogens. The novel RT-LAMP-BART assay to detect SARS-CoV-2 was highly specific compared to the conventional real-time RT-PCR. Within 25 min, the RT-LAMP-BART assay detected 80 copies of the target gene in a sample, whereas the conventional real-time RT-PCR method detected 5 copies per reaction within 130 min. Using RNA-spiked specimens, the sensitivity of the RT-LAMP-BART assay was slightly attenuated compared to purified RNA as a template. The results were identical to those of the conventional real-time RT-PCR method. Furthermore, using a peptide nucleic acid (PNA) probe, the RT-LAMP-BART method correctly identified the L452R spike mutation. This is the first report describes RT-LAMP-BART as a simple, inexpensive, rapid, and useful assay for detection of SARS-CoV-2, its variants of concern, and for screening of COVID-19.