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In vertebrates, skeletal muscle comprises fast and slow fibers. Slow and fast muscle cells in fish are spatially segregated; slow muscle cells are located only in a superficial region, and comprise a small fraction of the total muscle cell mass. Slow muscles support low-speed, low-force movements, while fast muscles are responsible for high-speed, high-force movements. However, speed and strength of movement are not binary states, but rather fall on a continuum. This raises the question of whether any recruitment patterns exist within fast muscles, which constitute the majority of muscle cell mass. In the present study, we investigated activation patterns of trunk fast muscles during movements of varying speeds and strengths using larval zebrafish. We employed two complementary methods: calcium imaging and electrophysiology. The results obtained from both methods supported the conclusion that there are spatially-ordered recruitment patterns in fast muscle cells. During weaker/slower movements, only the lateral portion of fast muscle cells is recruited. As the speed or strength of the movements increases, more fast muscle cells are recruited in a spatially-ordered manner, progressively from lateral to medial. We also conducted anatomical studies to examine muscle fiber size. The results of those experiments indicated that muscle fiber size increases systematically from lateral to medial. Therefore, the spatially ordered recruitment of fast muscle fibers, progressing from lateral to medial, correlates with an increase in fiber size. These findings provide significant insights into the organization and function of fast muscles in larval zebrafish, illustrating how spatial recruitment and fiber size interact to optimize movement performance., Competing Interests: Declarations. Ethics approval and consent to participate: All protocols for this study were approved by the animal care and use committees of the National Institutes of Natural Sciences. Experiments were performed at the Center for Animal Resources and Collaborative Study in Okazaki, in accordance with relevant guidelines regulations. This study was carried out in compliance with the ARRIVE guidelines for involvement of animals (fish). Consent for publication: Not applicable. Competing interests: Not applicable., (© 2025. The Author(s).)

The ability of "target tracking," such as keeping a target object in sight, is crucial for various activities. However, most sensing systems experience a certain degree of delay due to information processing, which challenges accurate target tracking. The long history of studies on animal behavior has revealed several tactics for it, although a systematic understanding of how individual tactics are combined into a strategy has not been reached. This study demonstrates a multifaceted tracking strategy in animals, which mitigates the adverse delay effects with small implementation costs. Using an active-sensing bat to measure their sensing state while chasing natural prey, we found that bats use a tracking strategy by combining multiple echolocation and flight tactics. The three echolocation tactics, namely the predictive control of sensing direction accompanied by adjusting the sensing rate and angular range, produce a direct compensation effect. Simultaneously, the flight tactic, the counter maneuver, assists echolocation by stabilizing the target direction. Our simulation results demonstrate that these combined tactics improve tracking accuracy over a wide range of delay constraints. In addition, a concise rule based on the angular velocity between bats and targets explains how bats control these tactics, suggesting that bats successfully reduce the burden of multitasking management. Our findings reveal the sophisticated strategy in animals' tracking systems and provide insights into understanding and developing efficiently integrated strategies in target tracking across various disciplines., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

RNA vaccines based on lipid nanoparticles (LNPs) with in vitro transcribed mRNA (IVT-mRNA) encapsulated are now a currently successful but still evolving modality of vaccines. One of the advantages of RNA vaccines is their ability to induce CD8 + T-cell-mediated cellular immunity that is indispensable for excluding pathogen-infected cells or cancer cells from the body. In this study, we report on the development of LNPs with an enhanced capability for inducing cellular immunity by using an ionizable lipid with a vitamin E scaffold. An RNA vaccine that contained this ionizable lipid and an IVT-mRNA encoding a model antigen ovalbumin (OVA) induced OVA-specific cytotoxic T cell responses and showed an antitumor effect against an E.G7-OVA tumor model. Vaccination with the LNPs conferred protection against lethal infection by Toxoplasma gondii using its antigen TgPF. The vitamin E scaffold-dependent type I interferon response was important for effector CD8 + T cell differentiation induced by the mRNA-LNPs. Our findings also revealed that conventional dendritic cells (cDCs) were essential for achieving CD8 + T cell responses induced by the mRNA-LNPs, while the XCR1-positive subset of cDCs, cDC1 specialized for antigen cross-presentation, was not required. Consistently, the mRNA-LNPs were found to selectively transfect another subset of cDCs, cDC2 that had migrated from the skin to lymph nodes, where they could make vaccine-antigen-dependent contacts with CD8 + T cells. The findings indicate that the activation of innate immune signaling by the adjuvant activity of the vitamin E scaffold and the expression of antigens in cDC2 are important for subsequent antigen presentation and the establishment of antigen-specific immune responses.

The escape trajectory (ET) of prey - measured as the angle relative to the predator's approach path - plays a major role in avoiding predation. Previous geometric models predict a single ET; however, many species show highly variable ETs with multiple preferred directions. Although such a high ET variability may confer unpredictability to avoid predation, the reasons why animals prefer specific multiple ETs remain unclear. Here, we constructed a novel geometric model that incorporates the time required for prey to turn and the predator's position at the end of its attack. The optimal ET was determined by maximizing the time difference of arrival at the edge of the safety zone between the prey and predator. By fitting the model to the experimental data of fish Pagrus major , we show that the model can clearly explain the observed multiple preferred ETs. By changing the parameters of the same model within a realistic range, we were able to produce various patterns of ETs empirically observed in other species (e.g., insects and frogs): a single preferred ET and multiple preferred ETs at small (20-50°) and large (150-180°) angles from the predator. Our results open new avenues of investigation for understanding how animals choose their ETs from behavioral and neurosensory perspectives., Competing Interests: YK, HA, KS, GN, HK, NN, PD No competing interests declared, (© 2023, Kawabata et al.)

Many laboratory experiments on aquatic vertebrates that inhabit closed water or coastal areas have highlighted negative effects of fast growth on swimming performance. Nonetheless, field studies on pelagic fishes have provided evidence of survival advantages of faster-growing individuals. To reconcile this contradiction, we examined the relationship between growth rate and swimming performance as a continuous function for juveniles of chub mackerel (Scomber japonicus) using 3D tracking analysis. For experiments, 20, 24, 27, and 30 days post-hatch individuals within the size range of 14.5-25.3 mm were used. We found that the growth-swimming (burst speed) relationship in chub mackerel was substantially positive and it was supported by morphological traits such as muscle area, which were also positively related with growth rate. This finding is consistent with field observations showing selective survival of fast-growing individuals of this species, reconciling the current contradiction between laboratory experiments and field observations. A dome-shaped quadratic curve described the relationship between growth rate and burst speed better than a linear or cubic function, suggesting that growth may trade-off with swimming performance, as reported in many previous studies, when it is extremely fast. These results, obtained from the rarely tested offshore species, strongly suggests the importance of experimental verification using animals that inhabit various types of habitats in understanding the principles underlying the evolution of growth-locomotor relationship., (© 2022. The Author(s).)

The most active and efficient catalysts for the electrochemical hydrogen evolution reaction (HER) rely on platinum, a fact that increases the cost of producing hydrogen and thereby limits the widespread adoption of this fuel. Here, a metal-free organic electrocatalyst that mimics the platinum surface by implementing a high work function and incorporating hydrogen-affine hydrogen bonds is introduced. These motifs, inspired from enzymology, are deployed here as selective reaction centres. It is shown that the keto-amine hydrogen-bond motif enhances the rate-determining step in proton reduction to molecular hydrogen. The keto-amine-functionalized polymers reported herein evolve hydrogen at an overpotential of 190 mV. They share certain key properties with platinum: a similar work function and excellent electrochemical stability and chemical robustness. These properties allow the demonstration of one week of continuous HER operation without notable degradation nor delamination from the carrier electrode. Scaled continuous-flow electrolysis is reported and 1 L net molecular hydrogen is produced within less than 9 h using 2.3 mg of polymer electrocatalyst., (© 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Although animal-borne accelerometers are effective tools for quantifying the kinematics of animal behaviors, quantifying the burst movements of small and agile aquatic animals remains challenging. To capture the details of burst movements, accelerometers need to sample at a very high frequency, which will inevitably shorten the recording duration or increase the device size. To overcome this problem, we developed a high-frequency acceleration data-logger that can be triggered by a manually defined acceleration threshold, thus allowing the selective measurement of burst movements. We conducted experiments under laboratory and field conditions to examine the performance of the logger. The laboratory experiment using red seabream ( Pagrus major ) showed that the new logger could measure the kinematics of their escape behaviors. The field experiment using free-swimming yellowtail kingfish ( Seriola lalandi ) showed that the loggers trigger correctly. We suggest that this new logger can be applied to measure the burst movements of various small and agile animals., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2018. Published by The Company of Biologists Ltd.)

Objectives: As a less invasive alternative to bronchoalveolar lavage (BAL), bronchoscopic microsampling (BMS) was developed to identify molecules present in the epithelial lining fluid (ELF) of the distal airways. Here, we evaluated the utility of BMS for serial collection of ELF in a canine lung transplant model., Methods: ELF was collected hourly by BMS up to 5 hours after reperfusion in a canine left lung transplant model. Tumor necrosis factor (TNF)-α levels in ELF were measured using an enzyme-linked immunosorbent assay and were compared with those in BAL fluid., Results: Serial collection of ELF by BMS in graft lungs was possible without adverse effects. However, the partial pressure of oxygen was markedly decreased because of ischemia-reperfusion lung injury. Probe ELF absorption ranged from 1-18 µL. TNF-α expression was significantly elevated and detected for 5 hours after reperfusion, whereas it was very low in the sham-operated group (p < 0.05). TNF-α concentration in BAL fluid was less than one-hundredth of that in ELF., Conclusions: BMS was safe and effective for serial ELF collection in grafted lungs. Temporal changes in TNF-α corresponded with ischemia-reperfusion lung injury. This is the first study to adopt BMS to elucidate pulmonary function after lung transplantation.

There has always been a conflict between the proposition that surgical methods for treating lung cancer should completely remove the lesion and the seemingly contradictory proposition that they should be as minimally invasive as possible. The achievement of radicality has been pursued by specializing, and began in 1933 when Graham performed total pneumonectomy for lung cancer. In 1960, the current surgical "gold standard" for lung cancer was reached when anatomical lobectomy and lymph node dissection were performed by Cahan, and subsequently called "radical lobectomy." The pursuit of less invasiveness began in the early 1980s, after the achievement of radicality, and thoracoscopic lobectomy has been developed as a major advance. Thoracoscopic lobectomy differs only in the method of accessing the pleural cavity: the surgical procedure within the pleural cavity does not differ from the procedure for radical lobectomy. In addition, the outcome of patients who have undergone thoracoscopic lobectomy as a form of minimally invasive surgery has been reported to be better than that after open lobectomy, and it is now clear that thoracoscopic lobectomy contributes to improving patients' postoperative quality of life. Accumulating additional cases and further study will be necessary in the future.

Background: Many cancer patients suffer from rapidly-progressing dyspnea that is difficult to relieve., Methods: The subjects were 26 patients who had dyspnea that was difficult to relieve. The Numeric Rating Scale was used to evaluate their dyspnea. For all patients, the cause of the dyspnea was investigated by CT and x-rays., Results: The principal causes of the dyspnea were pleural effusion that increased daily, complications from pneumonia, massive ascites, multiple metastatic lung tumors and atelectasis, recurrent laryngeal nerve paralysis and narrowing secondary airway compression. Dyspnea was caused by a variety of conditions that overlapped over time, intensifying patients' discomfort. Among 14 patients for whom we recommended treatment with sedation, only 8 of them consented. Among the patients who were treated with sedation, the median interval between the exacerbation of dyspnea and death was 16 days; among non-sedated patients it was 18 days., Conclusions: Palliative care physicians who specialize in the respiratory system can, to some extent, predict the occurrence of rapidly progressive dyspnea in cancer patients. It is important to explain the methods of relieving dyspnea to the patient, the patient's family, and the oncologist early, so that decisions on how to manage dyspnea can be made in advance.

We experienced a patient with an ileal artificial anus who suffered from abdominal pain caused by peritoneal dissemination of ovarian cancer, for which slow-release oxycodone was ineffective, but fentanyl patch proved effective. The patient was a 28-year-old female who developed abdominal pain caused by peritoneal dissemination on postoperative day 60 after radical hysterectomy and colostomy. For pain relief, administration of 10-mg slow-release oxycodone and 180-mg loxoprofen sodium was begun. When the dose was increased to 25 mg on postoperative day 240, the slow-release oxycodone in its original form was confirmed in feces from the artificial anus.When the same drug was changed to a fentanyl patch(12. 5 mg/hr), the pain was relieved. A palliative care doctor needs much knowledge regarding the changes in the patient's body with the progress and treatment of cancer, in addition to the drug mechanism.

Objective: With the discovery of novel opioids in recent years, it has become feasible to alleviate various forms of cancer pain. If the characteristics of individual opioids are exploited depending on pain-related factors in cancer patients may yield satisfactory pain relief with a low incidence of adverse reactions., Methods: This study involved 10 patients (5 male and 5 female) with cancerous abdominal pain, for whom the original opioid regimen was switched to morphine alone or continued in combination with morphine. The primary disease was gastric cancer in 5 patients, and uterine cervix, ovary cancer, leukemia, malignant pleuroperitoneal mesothelioma, and colon cancer in 1 patient each. Pain assessment was carried out using the Numerical Rating Scale., Results: In all the 10 cases, the opioid administered first was fentanyl; the pain relief was inadequate. Satisfactory pain relief was achieved in all patients by switchover to morphine alone or by concomitant administration of morphine with fentanyl., Conclusion: Enhanced gastrointestinal motility accounts, at least in part, for cancerous abdominal pain. Further, this kind of pain can be relieved by suppression of gastrointestinal motility with morphine.

Background: Blunt chest trauma resulting in massive hemothorax requires immediate attention. We investigated the diagnostic and prognostic utility of various clinical factors in patients with deep pulmonary laceration caused by blunt chest trauma with a view toward interventional treatment., Methods: We reviewed 42 patients with deep pulmonary laceration resulting from blunt chest trauma who were treated between 1988 and 2008. Various clinical factors were compared between survivors and nonsurvivors., Results: Of the 42 patients, 29 (69%) survived. Median (25th, 75th percentile) systolic blood pressure at arrival was 102 (76, 121) mm Hg for survivors and 70 (60, 90) mm Hg for nonsurvivors (p = 0.015). The median heart rate at arrival was 107 (98, 120) beats/min for survivors and 130 (120, 140) beats/min for nonsurvivors (p = 0.014). Respiratory rate, Glasgow Coma Scale score, and arterial blood gas values did not affect prognosis. Blood loss through the chest tube at insertion was 500 (400, 700) mL for survivors and 700 (500, 1000) mL for nonsurvivors (p = 0.147) and within 2 hours of arrival was 850 (590, 1100) mm Hg and 1600 (1400, 2000) mL, respectively (p < 0.001). Blood loss during thoracotomy was 1170 (600, 1790) mL and 3500 (2000, 6690), respectively (p < 0.001)., Conclusions: In patients with deep pulmonary laceration, hemorrhagic shock with systolic blood pressure less than 80 mm Hg and heart rate more than 120 beats/min leads to a poor prognosis. Emergency thoracotomy and pulmonary lobectomy should be performed before the intrathoracic hemorrhage reaches 1200 mL., (2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The palliative care team's roles are to provide a symptom relief to cancer patients, help them accept their medical conditions, and offer advice regarding the selection of appropriate medical treatments to suit their needs. Seeking the comfort of their homes, patients prefer a home care of superior medical care provided at hospitals. In 2008, 25 of the end-stage cancer patients at hospitals were expressed their desires to have a home medical care, and 10 of them were allowed to do so. We considered the following contributing factors that a patient should have for a smooth transition from hospital care to home medical care: (1) life expectancy of more than 2 months, (2) no progressive breathing difficulties experienced daily, (3) good awareness of medical condition among patients and families, (4) living with someone who has a good understanding of the condition, (5) availability of an appropriate hospital in case of a sudden change in medical requirements, and (6) good collaboration between emergency care hospitals, home physicians, and visiting nurses. To treat the end-stage cancer patients at home, there is a need for information sharing and a joint training of physicians specialized in cancer therapy, palliative care teams, home physicians, and visiting nurses. This would ensure a sustainable "face-to-face collaboration" in community health care.

Injury to the right diaphragm is sometimes missed in the acute stage and is detected only when the rupture becomes more extensive, a diaphragmatic hernia develops, and dyspnea ensues. We report a case in which spontaneous right pneumothorax developed 46 months after blunt trauma due to a fall. Air had leaked into the right pleural cavity, passed through the injured right diaphragm, and entered the abdominal cavity; the patient presented with intraperitoneal emphysema.

Background: Endobronchial bleeding in patients with blunt chest trauma can lead to death by suffocation. The conditions leading to bronchial bleeding usually require surgical treatment; however, for diffuse lung contusion, conservative treatment is possible if the bronchial bleeding can be controlled., Methods: Sites, methods, and outcomes of occlusion of the affected bronchus by endobronchial blocker used with a Univent endotracheal tube (Fuji Systems Corporation, Tokyo, Japan) in 35 patients (29 men, 6 women; mean age, 26 +/- 13 years) with diffuse lung contusion, treated from 1988 to 2004, were analyzed., Results: The right main bronchus was occluded in 7 patients, left main bronchus in 12, intermediate bronchial trunk in 9, and secondary bronchi in 7. Four patients who developed hypoxemia underwent differential ventilation. Bronchial occlusion was performed 118 +/- 139 minutes after arrival and continued 26 +/- 13 hours. Twenty-nine patients survived; 1 died of pulmonary abscess and 5 died due to brain injury., Conclusions: Bronchial occlusion should be performed soon after trauma in patients with endobronchial bleeding. The Univent has three advantages in such patients: (1) it prevents the inflow of blood from the affected bronchus into the unaffected lung; (2) the tamponade effect of the endobronchial blocker stops bronchial bleeding; and (3) air embolus due to air flowing from the bronchus into the pulmonary veins can be prevented. Use of a tube for one-lung ventilation with which the trauma surgeon is familiar is advisable. The Uniblocker tube (Fuji Systems Corporation) allows occlusion of the affected bronchus without reinsertion of a single-lumen tracheal tube.

Objective: Advantages and disadvantages have been reported for both internal pneumatic stabilization and surgical stabilization as treatments for anterior flail chest. We retrospectively investigated therapeutic outcomes and problems associated with pneumatic stabilization for anterior flail chest patients., Methods: Subjects were 43 patients admitted to Tokai University Hospital with anterior flail chest, 1988-1999. Pneumatic stabilization was performed with continuous positive pressure ventilation and a positive end-expiratory pressure of 10 cm H20 or higher. We analyzed mean times required for pneumatic stabilization, weaning, and mechanical ventilation; sternal fracture (presence vs. absence); survival, and other clinical variables., Results: Continuous positive pressure ventilation was needed for 12.5 days and mechanical ventilation for 15.6 days. Flail chest was relieved by pneumatic stabilization alone in 42 patients; 1 patient with a displaced sternal fracture required sternal fixation. Four cases were complicated by pneumonia. Pneumatic stabilization allowed physicians to treat severe combined nonthoracic organ injuries during the acute phase. Forty patients survived, and 3 died from nonthoracic injuries (survival rate 93%)., Conclusions: Anterior flail chest unaccompanied by sternal fracture can be relieved by pneumatic stabilization alone. We hope to combine pneumatic stabilization with simple surgical stabilization in anterior flail chest patients to shorten the mechanical ventilation period.

Since 1994, we have performed video-assisted thoracoscopic surgery in order to treat thoracic trauma. In general, emergency surgery is performed for trauma injuries incurred by knives. Between 1994 and 2005, we performed thoracoscopic surgery on eighteen cases of thoracic stab wounds. Among these eighteen cases, two were characterized by wounds to the internal thoracic artery, and they had to be switched over to open thoracotomy due to excessive bleeding. In conclusion, open thoracotomy should be performed in cases in which the patient is in a state of shock due to severe intrathoracic bleeding; however, in cases in which the vital signs are stable, thoracoscopic surgery may be carried out to stop intrathoracic bleeding, to repair the lung injury by suturing, as well as by performing a partial resection of the lung.

Case: A 41-year-old man survived deep pulmonary and hepatic lacerations by treatment with fluid resuscitation, blood transfusion, thoracotomy, and transcatheter hepatic artery embolization. The patient was transferred to our hospital 46 minutes after his motorbike struck a station wagon from behind. Hemorrhagic shock with systolic blood pressure of 68 mmHg was observed. He showed nonresponse to 20-minute intravenous infusion of 1,500 mL of lactated Ringer's solution. The initial plain chest radiograph showed mediastinal deviation to the left, radio-opacity of the right lower lobe, and decreased radiolucency of the right thorax. Rapid drainage of 800 mL of blood through a right chest tube led to a diagnosis of a deep pulmonary laceration of the right lower lobe. Abdominal computed tomography revealed another deep laceration affecting 40% of the liver. A right lower lobectomy of the lung was performed at 169 minutes after arrival. After the thoracotomy,transcatheter arterial embolization of the right hepatic artery was performed. The patient was discharged on hospital day 57., Conclusion: Prompt diagnosis and appropriate treatment are necessary to save patients with multiple, severe blunt injuries. Advanced Trauma Life Support (ATLS) guidelines should be adhered to for appropriate early treatment of patients with severe trauma.

Diffuse malignant mesothelioma with bloody pleural effusion is not rare, but a localized fibrous mesothelioma with bloody pleural effusion is relatively rare. A 45-year-old woman presented with a localized fibrous mesothelioma causing a bloody pleural effusion. Her chief complaint was right-sided lateral chest pain. A chest roentgenogram demonstrated a right-sided pleural effusion, so a chest tube was inserted, and the bloody fluid drained. A preoperative diagnosis of localized fibrous mesothelioma was made based on chest computed tomography and examination of computed tomographic guided percutaneous needle biopsy specimen. At operation, the tumor seemed to have originated from the right lung parenchyma or had invade the right lower lobe because tumor had penetrated deeply in the lung. Tumor and part of the parietal pleura were resected by right lower lobectomy. Final pathology established that the tumor was adherent to the right lung and was only encapsulated by the lung.

The correlation between detection of occult neo-plastic cells (ONCs) in lymph node sinuses and the recurrence/metastasis of primary breast, lung, esophageal, and gastric cancer was examined. Among patients with Stage I-III cancer treated by radical resection with dissection of at least 10 lymph nodes, 40 patients who suffered recurrence/metastasis within 5 years post-operatively and 94 patients who did not have recurrence within 5 years were randomly selected. A total of 1,340 lymph nodes were subjected to immunohistochemical staining for cytokeratin to identify ONCs. Then the sensitivity, specificity, positive predictive value, and negative predictive value of ONCs were determined for predicting the recurrence of each cancer. These parameters were respectively 40.0, 75.9, 62.4, and 55.8% for breast cancer, while the respective values were 50.0, 77.4, 68.9, and 60.8% for lung, 57.1, 64.3, 61.5, and 60.0% for esophageal, and 68.8, 65.0, 66.3, and 67.5% for gastric cancer. All of the parameters exceeded 65% for gastric cancer. ONCs also showed a high specificity for breast and lung cancer, but both the sensitivity and specificity were low for esophageal cancer.

Purpose: Patients with small adenocarcinoma of the lung (SACL) generally have a good prognosis. However, some SACL cases show lymph node metastasis, with poor prognosis. The expression pattern of 11p15 mucins (clustered on the p15 arm of the chromosome 11) is known to change during carcinogenesis in lung cancer., Experimental Design: We evaluated the expression of the 11p15 mucins (MUC2, MUC5AC, and MUC6) in 79 surgical specimens of SACL cases by immunohistochemical analysis. Lymph node metastasis was estimated by pathological staging., Results: Six (7.6%) and 11 (13.9%) of the 79 SACL cases showed MUC2 and MUC6 expression, respectively. Three SACL cases showed both MUC2 and MUC6 expression, and a significant correlation was found between MUC2 and MUC6 expression (Fisher's test, P = 0.033). Six (7.6%) SACL cases showed MUC5AC expression. Five of the 6 cases with MUC2 expression and 6 of the 11 cases with MUC6 expression were had lymph node metastasis. SACL cases with MUC2 or MUC6 expression showed a significantly higher incidence of nodal metastasis than those without expression (P < 0.001 and P = 0.006, chi(2) test, respectively). There was no significant correlation between MUC5AC expression and nodal involvement in SACL, whereas three of the six cases with MUC5AC expression showed lymph node metastasis. The SACL cases with MUC2 expression had a significantly poorer prognosis than those without MUC2 expression (P = 0.011, log-rank test)., Conclusions: These results suggest that 11p15 mucins MUC2 and MUC6 are related to lymph node metastasis in SACL.

Early peripheral lung cancer is defined as a tumor whose diameter is within 20 mm and that has not metastasized to lymph nodes. We developed thoracoscopic surgery (two windows method) in 1993. We have been conducting this thoracoscopic surgery in early peripheral lung cancers to identify possible indications as well as to clarify problems related to early peripheral lung cancer. The subjects of this study were 176 tumors, with diameters within 30 mm, including 97 lung cancers with diameters within 20 mm. Of the 97 tumors 20 mm or less in diameter, 18 were N 1 or more severe (N 1, 8 cases: N 2, 10 cases). One patient (N 2) died of bone metastasis and two patients died due to diseases other than lung cancer. Nearly 20% of the patients with tumors 20 mm or less were in the advanced stage, suggesting that mediastinal lymph node resection is necessary. Based on these results, it is advisable to define tumors with a diameter of no more than 10 mm as early peripheral lung cancer.

The purpose of this study was to evaluate the correlation between fluorine-18 fluorodeoxyglucose (FDG) thymic uptake and a normal appearing thymus on CT. Non-attenuation corrected FDG positron emission tomography (PET) data from 94 young persons (mean age 25.4 years, range 18-29 years) with a normal thymus diagnosed on CT were retrospectively evaluated. No subject had clinical symptoms suggestive of thymus-related disease or mediastinal tumour (follow-up period 6-69 months). PET images were visually assessed and the count ratio between the thymus and the lung (T/L ratio) was calculated. Increased FDG uptake occurred in 32 (34%) subjects. In these 32 cases, the T/L ratio was 2.86+/-0.49 (range 2.02-3.99). In 86 subjects whose CT images were available to calculate the CT attenuation of the thymus (CAT), the CAT value was -17.5+/-45.7 HU (range -103.6 HU to 79.9 HU). The T/L ratio correlated with the CAT value (r=0.58). CAT values in subjects with positive PET findings were significantly higher than CAT values in subjects with negative PET findings (p<0.001, unpaired t-test). These results suggest that even in young adults, if the thymus has a relatively high CT attenuation value, the presence of physiological thymic uptake in FDG-PET is a normal variant. In this study, the diagnosis of normal thymus was based on CT appearance and clinical course. Further studies are needed to clarify the relationship between histopathology and FDG uptake in the thymus.

Unlabelled: The adenomatous polyp of the colon is clinically important as a precursor of colonic cancer. The aim of this preliminary study was to evaluate the potential usefulness of (18)F-FDG PET for detecting adenomatous polyps of the colon., Methods: We performed a retrospective study of 110 subjects who underwent both PET study and total colonoscopy. On nonattenuation-corrected PET images, focal distinct FDG accumulation along the large intestine was considered a positive finding, and the PET results were compared with colonoscopic findings. Histology and adenoma size were determined by polypectomy., Results: Fifty-nine adenomatous polyps, 5-30 mm in size, were found in 30 subjects by total colonoscopy. PET findings were positive for 14 of the 59 adenomas (24%). The positivity rate for PET images rose with the increase in size of the adenomas; it was 90% in adenomas (9/10) that were > or =13 mm. The overall false-positive rate was 5.5% (6/110 subjects)., Conclusion: Increased glucose metabolism is observed in colonic adenomas, and detectability with PET increases with the increase in adenoma size. Adenomas are premalignant lesions, and it is important to realize that colonic adenomas may be found incidentally during an FDG PET study.

Background: Deep pulmonary laceration (DPL) is rare and its survival rate is low. The present study focused on the prognostic factors of DPL., Methods: The present study concerned 17 DPL patients treated in Tokai University Hospital between 1988 and 1998. The prognostic factors of DPL were compared with systolic blood pressure (SBP), PaO2, and the volume of intrathoracic blood loss. Characteristic findings of initial chest roentgenograms of DPL were investigated., Results: Eleven patients were saved and 6 patients died. An SBP of less than 80 mm Hg on arrival at the hospital and a blood loss of more than 1,000 mL through the chest tube within 2 hours after arrival were poor prognostic factors. Hypoxemia on arrival was not a poor prognostic factor. Chest roentgenograms showed macular infiltrative shadow with moderate lung collapse and deviation of the mediastinal shadow toward the unaffected side. Selective bronchial occlusion with a Univent prevented suffocation by intrabronchial blood., Conclusions: Two poor prognostic factors of DPL are SBP less than 80 mm Hg on arrival and blood loss of more than 1,000 mL through the chest tube within 2 hours after arrival.

Background: Recently the pros and cons of limited surgery for small-sized peripheral non-small-cell lung cancers (PNSCLCs), such as omission of mediastinal dissection, etc., have been vigorously debated. We analyzed whether hilar/mediastinal lymph node metastases were present in 30 small-sized PNSCLCs., Material and Methods: In the nine years from 1990 to 1998, 294 lung cancer patients underwent lobectomy or pneumonectomy combined with hilar/mediastinal dissection in the Tokai University Hospital. Thirty of these patients diagnosed as having cT1N0M0 PNSCLC with tumor diameters of 1.5 cm or less by computed tomography, are evaluated in this article., Results: The 30 PNSCLC patients consisted of 14 males and 16 females with a mean age of 61 +/- 9 years. Twenty six patients (87%) had no hilar nor mediastinal lymph node metastases (pN0), one patient (3%) had a hilar lymph node metastasis (pN1), and three patients (10%) had mediastinal lymph node metastases (pN2)., Conclusions: Mediastinal lymph node metastases were histologically observed in 3 (10%) of 30 PNSCLC patients with tumor diameters of 1.5 cm or less. Our results show that mediastinal dissection is still necessary even for small-sized lung cancers.

Background: We have been performing it less invasively by making just two, small skin incisions (Two Windows Method) for lung cancer surgery. We assess the usefulness of VATS by the Two Windows Method in elderly patients., Methods: The subjects were 32 of the 75-year-old or older patients with primary lung cancer in our department. We assessed cases in which thoracotomy was performed and the cases in which VATS by Two Windows Method was performed, and compared postoperative complications, hospital deaths, and postoperative length of stay., Results: Operations by video-assisted thoracic surgery (VATS) by the Two Windows Method were completed in 20 of the 32 patients, and a conversion to thoracotomy was done in two patients (rate 9%). Ultimately, thoracotomy was performed in a total of 12 cases, including these two. In the thoracotomy patients, the most common postoperative complication was pneumonia/atelectasis (4 cases) secondary to poor sputum expectoration. There were 2 hospital deaths due to septicemia, and there was 1 due to pulmonary artery embolism. In the VATS patients, the rate of occurrence of postoperative complications was 30%, and clearly lower than the 67% among the thoracotomy patients (p<0.05). No hospital death occurred among the VATS patients. The postoperative hospital stay of the VATS patients (21 days) was shorter than that of the thoracotomy patients (31 days), (p<0.05)., Conclusions: VATS by the Two Windows Method is safer than thoracotomy, and it should be considered first for lung cancer surgery in the aged.

Background: Unilateral lung volume reduction procedures are used to treat pulmonary emphysema. The most significant technical problem with this operation is an air leak from the pulmonary stump. Bovine pericardium has been used to prevent air leaks but is associated with interstitial pneumonia and a high cost., Methods: The fold plication method was devised to prevent postoperative air leaks to avoid interstitial pneumonia, and to decrease cost. This technique was applied in 20 consecutive patients with emphysema who underwent a unilateral lung volume reduction operation via a thoracoscopic two windows approach., Results: The operative time was approximately 1 hour. There was minimal postoperative bleeding, no persistent air leaks, and no evidence of pneumonia. Pulmonary function improved in all patients., Conclusions: The unilateral fold plication method is an economical and safe alternative to bovine pericardial patching after lung volume reduction operation to prevent stump air leaks.

Background: We report on the usefulness of thoracoscopic surgery by the Two Windows Method in mediastinal diseases. While the positioning of the two-window skin incisions was originally decided for lung cancer, but we have been using precisely the same method to biopsy and remove mediastinal lesions., Methods: Thoracoscopic surgery by the Two Windows Method was performed in 40 cases in which it had been impossible to make a diagnosis by noninvasive methods. Access to the pleural cavity was achieved by making skin incisions in two places anterior and posterior to the inferior angle of the scapula in the fourth intercostal space., Results: Biopsy was performed in 17 of the 40 patients to make a histological diagnosis. It was possible to make a definitive histological diagnosis in all of the patients. Complete resection of a mediastinal tumor was performed in 23 patients, and the resection was concluded thoracoscopically by the Two Windows Method in 22 of these patients (95.7%), with the only exception of one patient in whom we converted to standard thoracotomy because of intraoperative bleeding. There were no postoperative complications and no perioperative deaths., Conclusions: We conclude that the Two Windows Method is also useful for the diagnosis and complete resection of mediastinal diseases and that this is a low-invasive and safe method.

Background: We present a novel invention (Thoraco Holder; Fuji Systems Corporation, Tokyo, Japan) for thoracoscopic surgery. Made of silicone, automatically stops bleeding from the chest wall, increases range of motion for manipulation, and decreases postoperative pain., Methods: Under general anesthesia using the Univent tube (Fuji Systems Corporation, Tokyo, Japan), two Thoraco Holders were used in each of 300 thoracoscopic procedures for lung cancer, mediastinal tumor, pneumothorax, chest trauma, and emphysema, most using the Two Windows Method)., Results: No patient experienced more than 10 mL of bleeding from the chest wall. In addition, analgesics were not needed by any patient for over 1 week. No patient experienced trouble caused by the Thoraco Holder., Conclusions: The Thoraco Holder is made of silicone. Silicone rubber causes less pain postoperatively. The silicone cuff (balloon) causes less bleeding from the chest wall. This Thoraco Holder is useful access for video assisted thoracoscopic surgery.

Background: Continuing to refine minimally invasive thoracoscopic surgical procedures, we have established the two-windows method., Methods: Skin incisions required by this method consist of a 2- to 3-cm skin incision posteriorly, and a 2- to 3-cm skin incision anteriorly in the fourth intercostal space, with the inferior angle of the scapula as the midpoint. We used this method to perform pulmonary lobectomies in combination with thoracoscopy and mediastinal lymph node dissection in 100 consecutive patients with lung cancer (preoperative diagnosis, stage I, T1 N0 M0)., Results: The mean operative time was 2 hours 46 minutes, the mean blood loss was 68.2 mL, and the mean number of mediastinal lymph nodes dissected was 24.3. In developing this minimally invasive thoracoscopic procedure, which facilitates mediastinal lymph node dissection, we realized that it is best performed through the fourth intercostal space. Because the tracheal bifurcation can be seen directly below this level, surgical manipulation in this area can be easily performed. This enables the same extent of mediastinal lymph node dissection as that performed during a standard thoracotomy. Another advantage of this method is that a standard posterolateral thoracotomy incision can be made whenever necessary by simply connecting the two incisions., Conclusions: We believe that the two-windows method is capable of serving as the standard method for the surgical treatment of stage I lung cancer.

Pulmonary lobectomy and mediastinal lymph node dissection was performed in 25 patients with Stage I lung cancer under thoracoscopic guidance using the two-windows method. A posterior skin incision (3 cm) and lateral skin incision (2 cm) were made in the 4th intercostal space centering on the inferior angle of the scapula. The site closest to the operating surgeon was used for direct vision, while the distant site was used for insertion of the thoracoscope. The mean operative time was 2 hours and 15 minutes, and the mean blood loss was 82.6 ml. The mean number of dissected mediastinal lymph nodes was 32. The length of hospitalization ranged from 5 to 17 days. Recovery was uneventful, and analgesics were not required by postoperative day 6. The two-windows method overcomes the three-dimentional inaccuracy due to the one-directional observation of the operative field employed during conventional thoracoscopy. In addition, since we developed this method for mediastinal lymph node dissection, the tracheal bifurcation can be confirmed under direct vision, increasing the accuracy of the procedure. The advantages of the two-window thoracoscopic method of pulmonary lobectomy are cosmesis, preservation of respiratory function, and reduced postoperative pain. In addition, there is reduced intraoperative bleeding and shortened operative time, while achieving mediastinal dissection similar to that of standard thoracotomy. The two-windows method of thoracoscopic pulmonary lobectomy is equal or superior to standard thoracotomy in every respect. This method should become the standard surgical technique for Stage I lung cancer.

We established a thoracotomy method in which visual observation and a thoracoscope are used in combination. This method requires only small dermal incision--a three-cm-long posterior and two-cm-long anterior incision--in the fourth intercostal space around the angulus inferior scapulae. Using this method, we performed lobectomy and mediastinal lymph node dissection on 20 lung cancer cases (preoperatively diagnosed as stage I, T1N0M0 cases). Because the conventional thoracoscopic surgery relies strictly on two-dimensional images obtained from a thoracoscope, stereoscopic information on the location of the operation could not be obtained. Our new method, however, in corporates both a direct view obtained from two small incisions and a view on a video monitor, so the surgeon has constant access to a stereoscopic information on the location of the operation. We found that this thoracotomy using a thoracoscope was not only very useful in terms of respiratory function, the alleviation of pain, and aesthetic appearance, but that it also reduced hemorrhaging during surgery, decreased the length of time required for the thoracotomy and suturing, and enabled mediastinal dissection equal to that of standard thoracotomy.

A patient had apical hypertrophic cardiomyopathy and left atrial myxoma. We believe that this is the first description of such a combination.