Using hemoglobin vesicles to treat operative hemorrhagic shock after pneu- monectomy in dog models: an experimental study

Hemoglobin vesicles (HbVs), considered as red blood cell substitutes, are liposomes encapsulating purified hemoglobin, with a phospholipid bilayer membrane (diameter: 250 nm; P50, 28 Torr). In this study, we aimed to investigate HbV function during hemorrhagic shock in lung resection and analyze the details of oxygen delivery. Left pneumonectomy was performed in dogs under mechanical ventilation, followed by rapid exsanguination of approximately 30% of the total circulating blood volume, which led to shock, reducing the mean arterial pressure (MAP) by approximately 60% of baseline. Subsequently, either 5% human serum albumin (HSA) or HbVs suspended in 5% HSA were infused for resuscitation. The MAP only recovered to 75% of baseline after HSA administration, but fully recovered (100%) after HbV administration, with significant differences between the groups (P < 0.005). Oxygen delivery was restored in the HbV group and was significantly higher than that in the HSA group (P < 0.0001). The infusion of HbVs dispersed in a 5% HSA solution compensated for the rapid loss of approximately 30% of the total circulating blood volume in a dog pneumonectomy model, even with impaired lung function. Thus, HbVs can be used for resuscitation from hemorrhagic shock during thoracic surgery.

Poly(2-ethyl-2-oxazoline)-Conjugated Hemoglobins as a Red Blood Cell Substitute

Hemoglobin wrapped covalently with poly(2-ethyl-2-oxazoline)s (POx-Hb) is characterized physicochemically and physiologically as an artificial O2 carrier for use as a red blood cell (RBC) substitute. The POx-Hb is generated by linkage of porcine Hb surface-lysines to a sulfhydryl terminus of the POx derivative, with the average binding number of the polymers ascertained as 6. The POx-Hb shows moderately higher colloid osmotic activity and O2 affinity than the naked Hb. Human adult HbA conjugated with POx also possesses equivalent features and O2 binding properties. The POx-Hb solution exhibits good hemocompatibility, with no influence on the functions of platelets, granulocytes, and monocytes. Its circulation half-life in rats is 14 times longer than that of naked Hb. Hemorrhagic shock in rats is relieved sufficiently by infusion of the POx-Hb solution, as revealed by improvements of circulatory parameters. Serum biochemistry tests and histopathological observations indicate no acute toxicity or abnormality in the related organs. All results indicate that POx-Hb represents an attractive alternative for RBCs and a useful O2 therapeutic reagent in transfusion medicine.

Polyoxazoline-conjugated porcine serum albumin as an artificial plasma expander for dogs

Veterinary medicine has made tremendous progress for domestic dogs, which are irreplaceable family members enriching human life. Nevertheless, no adequate supply system exists for their blood products. This study examined the synthesis, structure, safety, and efficacy of poly(2-ethyl-2-oxazoline)-conjugated porcine serum albumin (POx-PSA) as an artificial plasma expander for dogs. The aqueous POx-PSA solution showed moderately high colloid osmotic pressure and good blood cell compatibility. Actually, lyophilized powder stored for 1 year can regenerate into a homogeneous solution. The circulation half-life of POx-PSA in rats was 2.1-fold longer than that of naked PSA. Rats produced neither anti-PSA IgG antibody nor anti-POx IgG antibody, which suggests excellent immunological stealth properties of POx-PSA. Complete resuscitation of hemorrhagic shock in rats was achieved soon after injection of POx-PSA solution. Serum biochemistry tests and histopathological observations indicated no abnormality in the related organs. When POx-PSA was administered to dogs intravenously, (i) no serum biochemical or hematological alteration was observed, also (ii) no overt deterioration of animal health was observed. These results indicate that POx-PSA has potential as an artificial plasma expander for dogs.

Politics of COVID-19 vaccination in Japan: how governing incumbents' representation affected regional rollout variation

BACKGROUND

Despite initial delay, Japan's COVID-19 vaccination accelerated remarkably from May to September 2021 under the leadership of Prime Minister Yoshihide Suga. His "campaign" for vaccination, however, did not yield uniform results nationwide.

METHODS

To highlight political determinants for the regional variation, we employ ordinary least squares regression analyses to investigate how the share/presence of incumbent politicians belonging to the governing parties, the Liberal Democratic Party and Komei Party, influenced the varying progress of rollouts across prefectures as well as across cities/towns/villages. The data on the vaccination rate for all 47 prefectures was obtained from Government Chief Information Officer (CIO)'s Portal, Japan (GCPJ) approximately one month prior to the anticipated general election, the national election for the more important House of Representatives of Japan's bicameral parliament (Diet). The data for lower administrative units, though its availability was limited to only three prefectures, was obtained from the respective governments of Kagawa and Ehime and from a local newspaper in Gifu.

RESULTS

The findings reveal that at both prefectural and sub-prefectural administrative levels, the share/presence of the governing parties' representation in the national parliament had a positive and statistically significant effect on the region's vaccination progress, after controlling for the local proliferation of COVID-19 and demographic characteristics.

CONCLUSION

Our findings contribute insights into the understudied area of the contemporary COVID-19 health environment, namely how the political dynamics of democracy affect the pattern of vaccine dissemination in Japan.

TRIAL REGISTRATION

Not applicable.

Zinc Substituted Myoglobin-Albumin Fusion Protein: A Photosensitizer for Cancer Therapy

Myoglobin combined with human serum albumin (Mb-HSA) can be produced using yeast Pichia pastoris as a host strain, with secretion into the culture medium. This Mb-HSA fusion protein possesses identical O₂ binding affinity to that of naked Mb. The Mb unit is reconstituted with a zinc(II) protoporphyrin IX, yielding (zinc substituted Mb)-HSA, ZnMb-HSA. The photophysical property and singlet O₂ generation ability of ZnMb-HSA are equivalent to those of ZnMb. In vitro cell experiments revealed that ZnMb-HSA acts as a superior photosensitizer for photodynamic cancer therapy. It is noteworthy that ZnMb-HSA shows long circulation lifetime in vivo.

Core-Shell Structured Hemoglobin Nanoparticles as Artificial O2 Carriers

This paper describes the synthesis and O₂ binding properties of core-shell structured hemoglobin (Hb) nanoparticles (NPs), artificial O₂ carriers of five types, as designed for use as red blood cell (RBC) substitutes. Human adult Hbs were polymerized using α-succinimidyl-ω-maleimide and dithiothreitol in spheroidal shapes to create parent particles. Subsequent covalent wrapping of the sphere with human serum albumin (HSA) yielded 100 nm-diameter Hb nanoparticles (HbNPs). The HbNP showed higher O₂ affinity than that of RBC, but NPs prepared under a N₂ atmosphere exhibited low O₂ affinity. Entirely synthetic particles comprising recombinant human adult Hb and recombinant HSA were also fabricated. Using a recombinant Hb (rHb) variant in which Leu-β28 of the heme pocket had been replaced with Phe, we found somewhat low O₂ affinity of rHb(βL28F)NP. Particles made of stroma-free Hb (SFHb) containing natural antioxidant enzyme catalase (SFHbNP) formed a very stable O₂ complex, even in aqueous H₂O₂ solution. The SFHbNP showed good blood compatibility and did not affect the blood cell component functionality. The circulation half-life of SFHbNP in rats was considerably longer than that of naked Hb. All results indicate these Hb-based NPs as useful alternative materials for RBC and as a useful O₂ therapeutic reagent in diverse medical scenarios.

A case of cerebral infarction due to aplastic or twig-like middle cerebral artery after lung cancer surgery

Aplastic/twig-like middle cerebral artery is a rare vascular abnormality. We report a case of postoperative cerebral infarction caused by this disease. The patient is a male in his 40s. A 9-cm tumour was revealed to have invaded the superior vena cava from his right lung. He underwent right upper and middle bilobectomy. Due to the vascular invasion, the intraoperative bleeding exceeded 2 litres. Mechanical ventilation was required for postoperative pneumonia. After extubation, he was unable to write and was found to have cerebral infiltration in the left middle cerebral artery region. The cause of the cerebral infarction was investigated, but no thrombus in the left atrium or arteriosclerosis was found. No atrial fibrillation was observed during or after the surgery. Magnetic resonance angiography of the brain revealed an aplastic/twig-like middle cerebral artery.

POS0875 LATENT TRAJECTORY MODELING OF PULMONARY ARTERY PRESSURE IN SYSTEMIC SCLEROSIS: A RETROSPECTIVE COHORT STUDY

Background

Systemic sclerosis (SSc) is an autoimmune disease that is characterized by systemic vasculopathy and fibrosis. Pulmonary hypertension (PH), defined as elevated pulmonary arterial pressure (PAP), is one of the leading causes of death of SSc1. In recent years, various therapies have been developed to target each of the pathogenesis of SSc – autoimmunity, vasculopathy, and fibrosis. Accordingly, treatment strategies based on risk stratification for PH progression are aspired; however, prediction of changes in PAP in diverse patients with SSc has not been established2.

Objectives

To visualize the patterns of PAP elevation in SSc and to identify the clinical characteristics of each trajectory, by applying latent trajectory modeling for PAP measured repeatedly by echocardiography.

Methods

This was a multicenter, retrospective cohort study conducted at four referral hospitals in Kyoto, Japan. Patients with SSc who visited the study site between April 2008 and March 2021 and had at least three echocardiographic measurements of systolic pulmonary arterial pressure (sPAP) were included in this study. Follow-up concluded in March 2021. A group-based trajectory model3 was applied to the change in sPAP over time, and individual patients were classified into distinct subgroups that followed similar trajectories. The number and shape of the trajectories were estimated based on adequacy, goodness of fit, parsimony, and interpretability of the model. Clinical plausibility was assessed by comparing PH-free survival, i.e., time to either PH or death, for each trajectory. Multinomial logistic regression analysis was performed for baseline clinical characteristics associated with trajectory assignment.

Results

A total of 236 patients with a total of 1097 sPAP measurements were included. We identified five trajectories following the quadratic function as “rapid progression (n=9, 3.8%)”, “early elevation (n=30, 12.7%)”, “mid elevation (n=54, 22.9%)”, “late elevation (n=24, 10.2%)”, and “low stable (n=119, 50.4%)”. Each trajectory, in this order, showed earlier elevation of sPAP and shorter PH-free survival (Figure 1). In the multinomial logistic regression (with the “low stable” as reference), cardiac involvement was associated with the “rapid progression” (adjusted odds ratio [OR] 28.9, 95% confidence interval [CI] 3.21–259.5), diffuse cutaneous SSc was associated with the “early elevation” (OR 4.08, 95% CI 1.27–13.1), anti-centromere antibody positive was associated with the “mid elevation” (OR 4.50, 95% CI 1.11–18.2), and older age of onset was associated with the above three trajectories.

Conclusion

The pattern of changes in pulmonary artery pressure over time in SSc can be classified into five distinct trajectories. Each trajectory differed in baseline clinical characteristics and outcomes.

References

[1]Pokeerbux MR, et al. Survival and prognosis factors in systemic sclerosis: data of a French multicenter cohort, systematic review, and meta-analysis of the literature. Arthritis Res Ther. 2019;21(1):86.

[2]Denton CP, et al. Systemic sclerosis. Lancet. 2017;390(10103):1685-1699.

[3]Nagin DS, et al. Group-based trajectory modeling in clinical research. Annu Rev Clin Psychol. 2010;6:109-38.

Disclosure of Interests

None declared

Hemoglobin-albumin clusters as an artificial O2 carrier: Physicochemical properties and resuscitation from hemorrhagic shock in rats

A bovine hemoglobin (HbBv) or human adult hemoglobin (HbA) wrapped covalently by human serum albumins (HSAs), hemoglobin-albumin clusters (HbBv-HSA₃ and HbA-HSA₃ ), are artificial O₂ carriers used as a red blood cell substitute. This article describes the physicochemical properties of the HbBv-HSA₃ and HbA-HSA₃ solutions, and their abilities to restore the systemic condition after resuscitation from hemorrhagic shock in anesthetized rats. The HbBv-HSA₃ and HbA-HSA₃ , which have high colloid osmotic activity, showed equivalent solution characteristics and O₂ binding parameters. Shock was induced by 50% blood withdrawal. Rats exhibited hypotension and significant metabolic acidosis. After 15 min, the rats were administered shed autologous blood (SAB), HbBv-HSA₃ , HbA-HSA₃ , or Ringer's lactate (RL) solution. Survival rates, circulation parameters, hematological parameters, and blood gas parameters were monitored during the hemorrhagic shock and for 6 h after administration. All rats in the SAB, HbBv-HSA₃ , and HbA-HSA₃ groups survived for 6 h. The HbBv-HSA₃ and HbA-HSA₃ groups restored mean arterial pressure after the resuscitation. No remarkable difference was observed in the time courses of blood gas parameters in any resuscitated group except for the RL group. Serum biochemical tests showed increases in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the HbBv-HSA₃ and HbA-HSA₃ groups compared to the SAB group. Therefore, we observed other rats awakened after resuscitation with HbA-HSA₃ for 7 days. The blood cell count, AST, and ALT recovered to the baseline values by 7 days. All the results implied that HbBv-HSA₃ and HbA-HSA₃ clusters provide restoration from hemorrhagic shock as an alternative material for SAB transfusion.

Bioinspired carbon monoxide delivery using artificial blood attenuates the progression of obliterative bronchiolitis via suppression of macrophage activation by IL-17A

Carbon monoxide (CO) is expected to attenuate the progression of obliterative bronchiolitis (OB), which is a serious complication after lung transplantation. However, issues in terms of feasible exogenous CO supply, such as continuousness and safety, remain unsolved. Here, we applied nano red blood cells, namely hemoglobin vesicles (Hb-V), as a CO cargo based on the biomimetic concept and investigated the therapeutic potential of CO-loaded Hb-V on OB in orthotopic tracheal transplant model mice. The CO-loaded Hb-V was comprised of negatively charged liposomes encapsulating carbonylhemoglobin with a size of ca. 220 nm. The results of histological evaluation showed that allograft luminal occlusion and fibrosis were significantly ameliorated by treatment with CO-loaded Hb-V compared to treatment with saline, cyclosporine, and Hb-V. The therapeutic effects of CO-loaded Hb-V on OB were due to the suppression of M1 macrophage activation in tracheal allografts, resulting from decreased IL-17A production. Furthermore, the expression of TNF-α and TGF-β in tracheal allografts was decreased by CO-loaded Hb-V treatment but not saline and Hb-V treatment, indicating that CO liberated from CO-loaded Hb-V inhibits epithelial-mesenchymal transition. These findings suggest that CO-loaded Hb-V exerts strong therapeutic efficacy against OB via the regulation of macrophage activation by IL-17A and TGF-β-driven epithelial-mesenchymal transition.

A desmoplastic fibroblastoma that developed in the anterior mediastinum: a case report

BACKGROUND

Desmoplastic fibroblastoma (also known as collagenous fibroma) is a benign, slowly growing soft-tissue tumor. Most desmoplastic fibroblastomas develop in the limbs, neck, or trunk. A mediastinal origin is quite rare.

CASE PRESENTATION

A 32-year-old Asian female was referred to us for the diagnosis and treatment of an anterior mediastinal tumor. The tumor was 80 mm in the largest diameter and was located on the pericardium. No invasion was evident. She underwent resection of the tumor via video-assisted thoracoscopic resection. The tumor was totally encapsulated, and its pedicle was on the pericardium. The resected specimen was very rigid, making it difficult to remove from the intercostal space. Histologically, the tumor was composed of a paucicellular dense collagenous tissue. Mitosis was rarely observed, and cellular atypia was not evident, suggesting that the tumor was benign. We diagnosed the tumor as a desmoplastic fibroblastoma by morphology and immunohistochemistry.

CONCLUSIONS

Desmoplastic fibroblastoma of the mediastinum is an extremely rare disease. Preoperative diagnosis is difficult. Early surgical resection is suitable for diagnosis and treatment planning.

A surgical Case of Synchronous Multiple Primary Lung Cancers with Small Cell Carcinoma and Squamous Cell Carcinoma

The incidence of synchronous multiple primary lung cancers has increased in recent years, however, there are few reports of cases involving small cell carcinoma. A 72-year-old man was referred to our department because of an abnormal shadow on chest radiography. He was receiving treatment for pulmonary fibrosis, emphysema, rheumatoid arthritis, and prostate cancer. Computed tomography revealed two lung nodules in the left lower lobe. A definitive diagnosis was unable to be made based on transbronchial lung biopsy. Positron emission tomography demonstrated abnormal fluorodeoxyglucose uptake in the two lung nodules and lung cancer (cT3N0M0) was suspected. Thoracoscopic partial resection of the left lower lobe was performed. As primary lung cancer was diagnosed using the frozen specimen, we performed left lower lobectomy with lymph node dissection. Pathological examination of the S9 and S6 tumors revealed combined small cell carcinoma and squamous cell carcinoma, respectively. Both tumors were separated and diagnosed as synchronous multiple primary lung cancers. No lymph node metastasis was found. We report a rare case of synchronous multiple primary lung cancers, including small cell carcinoma.

Myxofibrosarcoma that Developed Rapidly in the Breast of an Elderly Man and Recurred Early after Surgery: A Case Report

BACKGROUND

Myxofibrosarcoma is a rare disease occurring subcutaneously in the limbs. We report a case of a rapidly growing myxofibrosarcoma in the breast of an elderly man that recurred early after surgery.

CASE PRESENTATION

A 73-year-old man presented with a breast mass. Physical findings showed a large tumor in the right breast, and malignancy was suspected on ultrasonography. Computed tomography (CT) revealed tumor invasion into the pectoralis major and pectoralis minor muscles. Positron emission tomography/CT showed no abnormality in other organs. Needle biopsy results excluded breast cancer but did not provide a definitive diagnosis. However, the tumor grew rapidly before further results were available, so emergency mastectomy was performed. The final pathological diagnosis was high-grade myxofibrosarcoma. Postoperative radiotherapy was started because of remnant tumor. The wound became worsened and swollen, and needle biopsy 10 days after the start of therapy indicated recurrence. Radical resection and thoracoplasty were performed. Postoperative pathological specimens showed no residual tumor. Radical radiation therapy was resumed. The patient has shown no recurrence after an year.

CONCLUSIONS

It is important to consult a soft tissue oncologist for tumors in the breast and perform appropriate examination and treatment if soft tissue tumors cannot be ruled out.

Immediate effects of systemic administration of normal and high O2-affinity haemoglobin vesicles as a transfusion alternative in a rat pneumonectomy model

BACKGROUND

Haemoglobin vesicles (HbVs) are red blood cell (RBC) substitutes with a phospholipid bilayer membrane and a polyethylene modified surface (diameter=250 nm; P₅₀=28 Torr). They can be preserved for years and can be used in patients of all blood types without the risk of infection. Their oxygen affinity can be modified by changing the allosteric effectors.

METHODS

Left pneumonectomy was performed under mechanical ventilation on rats, followed by rapid exsanguination of ~30% of the total circulating blood volume. Rat RBCs shed in 5% human serum albumin (HSA) solution (rat RBC), HbV with high oxygen affinity in 5% albumin solution (low-P₅₀ HbV, P₅₀=9 Torr), normal HbV suspended in 5% albumin (HbV, P₅₀=28 Torr) or 5% HSA was infused for resuscitation. Haemodynamics and oxygenation were evaluated.

RESULTS

Systemic arterial blood pressure significantly decreased after exsanguination and increased after each infusion. In the HbV, low-P₅₀ HbV and rat RBC groups, all rats were liberated from mechanical ventilation and blood pressure was stabilised, whereas 50% of the rats in the HSA group died within 1 hour after weaning from mechanical ventilation. The PaO₂ in arterial blood for 1 hour after liberation from mechanical ventilation in the rat RBC, HbV and low-P₅₀ HbV groups was 59.4±12.5, 58.3±10.1 and 70.5±14.5 mm Hg, respectively. The PaO₂ in the low-P₅₀ HbV group was significantly higher than those in the rat RBC and HbV groups (p=0.05 for both). Serum lactate elevations due to hypoxic damage were minimised by HbV, low-P₅₀ HbV as well as rat RBCs.

CONCLUSIONS

The oxygen-carrying ability of HbV was comparable to that of rat RBCs, even under impaired lung function after pneumonectomy. HbVs with high oxygen affinity may have more beneficial effects on oxygenation in pulmonary resection.

Postintubation tracheal stenosis 35 years after neonatal resuscitation

•

Granulation or cicatrization on the tracheal lumen increases after injury or ischemia caused by tubes or cuffs, results in narrowing of the trachea within a few months after extubation.

•

We have described a case of tracheal stenosis that manifested 35 years after endotracheal intubation for neonatal resuscitation.

•

The scar tissue was ablated using argon plasma coagulation, and no recurrence has been observed for more than 3 years.

•

Delayed postintubation tracheal stenosis should be taken into consideration, when a patient suffers from suffocating tracheal stenosis.

Introduction

Postintubation tracheal stenosis involves granulation or cicatrization of the tracheal epithelium. It is progressive and can become life-threatening within a few months after extubation.

Presentation of case

We here report a case of tracheal stenosis with a delayed manifestation, presenting 35 years after endotracheal intubation for neonatal resuscitation. A female patient complained of dyspnea during pregnancy. Bronchoscopy revealed 75% constriction of the tracheal lumen by cicatrization, from the 2nd to 4th tracheal rings. After child-birth, the scar tissue was ablated using argon plasma coagulation.

Discussion

The patient had no significant medical history, such as severe airway infection or cervical/chest trauma, which might have caused the circumferential cicatricial tracheal stenosis, other than the endotracheal intubation she had undergone for neonatal resuscitation. Therefore, we considered this to reflect postintubation tracheal stenosis with delayed manifestation.

Conclusion

Delayed postintubation tracheal stenosis should be taken into consideration, when a patient suffers from suffocating tracheal stenosis.

Analysis of key clinical features for achieving complete remission in stage III and IV non-small cell lung cancer patients

BACKGROUND

Although development of immune checkpoint inhibitors and various molecular target agents has extended overall survival time (OS) in advanced non-small cell lung cancer (NSCLC), a complete cure remains rare. We aimed to identify features and treatment modalities of complete remission (CR) cases in stages III and IV NSCLC by analyzing long-term survivors whose OS exceeded 3 years.

METHODS

From our hospital database, 1,699 patients, registered as lung cancer between 1^st Mar 2004 and 30^th Apr 2011, were retrospectively examined. Stage III or IV histologically or cytologically confirmed NSCLC patients with chemotherapy initiated during this period were enrolled. A Cox proportion hazards regression model was used. Data collection was closed on 13^th Feb 2017.

RESULTS

There were 164 stage III and 279 stage IV patients, including 37 (22.6%) and 51 (18.3%) long-term survivors and 12 (7.3%) and 5 (1.8%) CR patients, respectively. The long-term survivors were divided into three groups: 3 ≤ OS < 5 years, 5 years ≤ OS with tumor, and 5 years ≤ OS without tumor (CR). The median OS of these groups were 1,405, 2,238, and 2,876 days in stage III and 1,368, 2,503, and 2,643 days in stage IV, respectively. The mean chemotherapy cycle numbers were 16, 20, and 10 in stage III and 24, 25, and 5 in stage IV, respectively. In the stage III CR group, all patients received chemoradiation, all oligometastases were controlled by radiation, and none had brain metastases. Compared with non-CR patients, the stage IV CR patients had smaller primary tumors and fewer metastases, which were independent prognostic factors for OS among long-term survivors. The 80% stage IV CR patients received radiation or surgery for controlling primary tumors, and the surgery rate for oligometastases was high. Pathological findings in the stage IV CR patients revealed that numerous inflammatory cells existed around and inside resected lung and brain tumors, indicating strong immune response.

CONCLUSIONS

Multiple line chemotherapies with primary and oligometastatic controls by surgery and/or radiation might achieve cure in certain advanced NSCLC. Cure strategies must be changed according to stage III or IV. This study was retrospectively registered on 16^th Jun 2019 in UMIN Clinical Trials Registry (number UMIN000037078).

Current status of diagnostic and therapeutic bronchoscopy in Japan: 2016 national survey of bronchoscopy

BACKGROUND

The safety management committee of the Japan Society for Respiratory Endoscopy (JSRE) conducted national surveys to clarify the state of diagnostic and therapeutic bronchoscopy in 2016.

METHODS

Questionnaire forms were mailed to 532 JSRE-accredited facilities throughout Japan. We surveyed the actual condition of clinical practice and cases of bronchoscopy during 2016.

RESULTS

Four hundred and thirty-three facilities responded giving a response rate of 81.4%; 67.6% held more than 400 beds. The average number of board accredited senior Fellows and Fellows per facility was 1.9 and 3.2, respectively. Diagnostic bronchoscopy was performed in a hospitalized setting in 74.6% of all facilities. The radial type ultrasound probe was operated in 51.7% of all facilities. The number of facilities has markedly increased compared with that reported in the 2010 survey (19.6%). The bronchoscopic navigation system had been in operation in 41.7% of all facilities. Antithrombotic drugs were adjusted before biopsy in 96.8% of all facilities. For intravenous sedation, midazolam was the first choice in 76.9% of all facilities. Endobronchial ultrasound guided transbronchial lymph node needle aspiration (EBUS-TBNA) has become popular over the decade (19.6% in 2010 to 68.1% in 2016). The mean number of the board accredited senior Fellows and board accredited Fellows increased in comparison with that in 2010. As a new technique, radial type ultrasound-guided peripheral approach has become popular.

CONCLUSIONS

Through this survey, the advanced safety of bronchoscopic examination has been secured in many facilities. A continuous monitoring of bronchoscopic practices with respect to safety management is recommended.

A Case of Mediastinal Lymph Node Carcinoma of Unknown Primary Site

A 63-year-old man was pointed out with a mediastinal tumor on chest computed tomography (CT). On positron emission tomography-CT, fluorodeoxyglucose accumulation with a maximum standardized uptake value of 12.70 was seen in this tumor. Scar-like nodule was found in the apex of the right lung, but no abnormal accumulation was observed in this nodule. The level of carcinoembryonic antigen was abnormally elevated. We performed mediastinal tumorectomy under thoracoscopic surgery. Since arterial oxygen saturation fell during intraoperative one-lung ventilation, we finished the surgery without resection of right apex nodule. Histologically, mediastinal tumor was diagnosed as metastatic adenocarcinoma in lymph node. Because immunohistochemical staining suggested lung adenocarcinoma as the primary site, the right apex nodule was resected. Pathological diagnosis of this nodule was scar fibrosis. No other malignant lesions were detected, and therefore we finally diagnosed this tumor as mediastinal lymph node carcinoma of unknown primary site. The patient was given adjuvant chemotherapy, and at present, 37 months after surgery, the patient remains free of the disease.

Initial experience with transbronchial cryoablation as a novel local treatment for malignant peripheral lung lesions

Introduction

Percutaneous cryoablation has been adopted for small, malignant peripheral pulmonary lesions and has yielded favourable results as a less invasive local treatment. A transbronchial approach may reduce the risks of complications, such as pneumothorax and pleural haemorrhage. A fundamental animal experiment on transbronchial cryoablation was performed to examine its immediate safety and effectiveness.

Methods

Experimental cryoablation was performed on swine lungs using a rigid cryoprobe, 2.4 mm in diameter. The probe was introduced from the right main bronchus into the distal bronchus via thoracotomy, perforated the end of the conducting bronchus and reached the lung parenchyma. The temperature of the cryoprobe tip reaches approximately −130°C during freezing and approximately 20°C during thawing. After three freeze-thaw cycles, the cryoprobe was removed.

Results

No significant haemorrhage was bronchoscopically observed in the airways throughout the experiment. The chronological changes and spatial distribution of the temperature of the pulmonary tissue circumferential to the point of the cryoprobe were similar to those seen with transpleural cryoablation and the less than −20°C thermal zone seemed to be established within a radius of at least 12 mm. The central destruction zone of alveolar structures was histologically similar to the thermal zone, while the conducting bronchus structure and the accompanying pulmonary artery were not severely affected.

Conclusion

Experimental transbronchial cryoablation with a rigid cryoprobe could effectively freeze and destroy peripheral lung alveoli without any significant immediate adverse effects. This may suggest the potential clinical application of transbronchial cryoablation for peripheral malignant lung lesions.

Anesthetic Management in Tracheal Dilatation for Severe Tracheal Stenosis

We report the anesthetic management of a 65-year-old woman with recurrent, severe tracheal stenosis who underwent tracheal dilatation. She had visited the Department of Respiratory Medicine at our hospital for respiratory distress approximately 20 years ago, and had undergone laser ablation under local anesthesia. Because of recurrence and aggravation of respiratory distress, she now presented at the Department of Thoracic Surgery, and was scheduled for surgery. Percutaneous cardiopulmonary support was prepared, and she was sedated with midazolam and dexmedetomidine. Under bronchoscopic guidance, a 5-mm intubation tube was placed directly above the stenosis site. Laser ablation (by argon plasma coagulation) and balloon dilatation were performed, and the tube was replaced with one with a larger diameter, which was subsequently replaced with another with an even larger diameter. Ultimately, a 7-mm tube was placed beyond the stenosis site, and the operation was completed. After restoration of spontaneous respiration and consciousness, the patient was extubated in the operating room and returned to the intensive care unit. In anesthetic management of patients with tracheal stenosis, treatment of hypoxia is important. In this case, we collaborated with the attending physician, clinical engineers, and operating room nurses throughout, and consequently, were able to perform the operation safely.

A Case of Primary Small Cell Carcinoma of the Cervical Esophagus with Long-term Survival following Concurrent Chemoradiotherapy: Case Report and Review of the Literature

The authors describe a case of small cell carcinoma of the esophagus that was treated by concurrent chemoradiotherapy. Both the esophageal tumor and the regional lymph node metastases disappeared after this treatment. The patient is alive and disease free after more than five years.

Primary small cell carcinoma of the esophagus is a rare and aggressive neoplasm with a very poor prognosis, and the treatment modality is controversial. This case illustrates the possibility of treating this tumor type with concurrent chemoradiotherapy.

Congenital cystic adenomatoid malformation in adults: Report of a case presenting with a recurrent pneumothorax and a literature review of 60 cases

Congenital cystic adenomatoid malformation (CCAM) is a congenital pulmonary cystic disease that is mostly detected and diagnosed prenatally or during the neonatal period, while rarely being observed in adults. Here, we report an adult case of CCAM that was diagnosed following surgery for a recurrent pneumothorax. We further review 60 case reports on adult CCAM that have been previously published. The patient was a 29-year-old woman with a severe left pneumothorax. Her computed tomography scan showed the presence of multiple pulmonary cysts at the base of the left lower lobe. Since she had experienced a left pneumothorax twice previously, surgery was indicated. A wedge lung resection of the pulmonary cysts was performed thoracoscopically. The postoperative pathological diagnosis was type I CCAM. From the review, 7 adult CCAM patients (11.7%) out of 61, including the patient in the present case, presented with pneumothorax, while 21 patients (35%) presented with infection. Thirty-nine foci of CCAM (65%) were located in lower lobes. Moreover, malignancies were associated in 8 cases (13.3%). We propose that if multicystic lung lesions are found in pneumothorax patients, particularly in lower lobes, CCAM should be considered during the differential diagnosis, even in adults.

Temporal Changes of Inflammatory Cytokine Profiles in Epithelial Lining Fluid in a Canine Lung Transplant Model

OBJECTIVES

Ischemia-reperfusion injury resulting in post-transplant lung dysfunction involves a complicated network of cytokines that has yet to be fully investigated. We analyzed temporal changes in cytokine levels in epithelial lining fluid (ELF) from the distal airways of a canine lung transplantation model.

METHODS

Ischemic time was set to 18 hours to enhance lung injury in a left single-lung transplantation model. ELF was collected via bronchoscopic microsampling, a minimally-invasive technique allowing repeated sampling, hourly up to 5 hours after reperfusion started. We compared levels of pro-inflammatory cytokines in ELF with those at baseline (time zero), and with a sham-operated control group.

RESULTS

Concentrations of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) significantly increased immediately after the start of lung reperfusion in the transplant group relative to the sham group (P < 0.005 and P < 0.05, respectively); both were sustained through the 5 hours. Interferon gamma (IFN-γ levels were significantly reduced 3 h after reperfusion started (P < 0.05).

CONCLUSIONS

We found time- and cytokine-dependent changes in TNF-α, IL-6, and IFN-γ in ELF from the lung transplantation model. These specific changes in the cytokine profile may relate to the mechanism underlying post-transplant lung dysfunction.

Acute 40% exchange-transfusion with hemoglobin-vesicles in a mouse pneumonectomy model

OBJECTIVES

Hemoglobin vesicles (HbVs) function as a red blood cell (RBC) substitute and are composed of purified hemoglobin encapsulated in a phospholipid bilayer membrane. The performance of HbVs as a substitute for RBC transfusions was examined in a mouse model of pneumonectomy following acute 40% exchange-transfusion with HbVs.

METHODS

Before performing left pneumonectomies, 40% of the blood volume of mice was replaced with a) lactated Ringer's solution (control), b) 5% recombinant human serum albumin (rHSA), c) mouse RBCs shed in rHSA (mRBCs/rHSA), or d) HbV suspended in rHSA (HbV/rHSA). We compared postoperative a) survival, b) functional recovery, and c) histopathological, immunohistochemical, and inflammatory responses among the study groups.

RESULTS

In the HbV/rHSA and mRBC/rHSA groups, all mice survived ≥7 days after pneumonectomy, whereas 100% of the control mice died within a few h and 50% of mice in the rHSA group died within 24 h after pneumonectomy. Immunohistochemical staining for hypoxia-inducible factor-1α showed that hepatic and renal hypoxic injuries were prominently mitigated by HbV and mRBCs.

CONCLUSIONS

The oxygen-carrying performance of HbV was similar to that of mRBCs, even with impaired lung functions following pneumonectomy. HbV infusion did not interfere with the recovery from surgical injury. In the near future, HbVs could be used clinically as a substitute for the perioperative transfusion of RBCs, when or where donated RBCs are not immediately available.

Acute Cerebellar Ataxia Induced by Nivolumab

A 54-year-old woman with adenocarcinoma of the lung and lymph node metastasis experienced nystagmus and cerebellar ataxia 2 weeks after initiating nivolumab therapy. An evaluation for several autoimmune-related antibodies and paraneoplastic syndrome yielded negative results. We eventually diagnosed the patient with nivolumab-induced acute cerebellar ataxia, after excluding other potential conditions. Her ataxic gait and nystagmus resolved shortly after intravenous steroid pulse therapy followed by the administration of decreasing doses of oral steroids. Nivolumab, an immune checkpoint inhibitor, is known to induce various neurological adverse events. However, this is the first report of acute cerebellar ataxia associated with nivolumab treatment.

Serial Epithelial Lining Fluid Collection Using Bronchoscopic Microsampling in a Canine Lung Transplantation Model

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.

Experimental Study of Intraparenchymal Fibrinogen and Topical Thrombin to Seal Pleural Defects

OBJECTIVE

Fibrin sealants are used to close surgical pleural defects, but may detach, causing a postoperative air-leak. We investigated a new means of applying fibrin glue for closing pleural defects.

METHODS

Pleural defects (10-mm and 4-mm diameters, respectively) were created in swine and rats via thoracotomy. They were sealed by a) injection of a fibrinogen solution into the lung parenchyma after instillation of a thrombin solution onto the pleural defect (group A), b) fibrinogen and thrombin spray (group B), c) fibrinogen instillation and a thrombin-dipped polyglycolic acid sheet (group C), or d) fibrin glue-coated collagen fleece (group D). Resistance to airway pressure was compared and the sealed areas were histologically examined.

RESULTS

In group A, the minimum seal-breaking airway pressure was consistently > 40 cmH2O, versus 37.2 ± 3.6 cmH2O in group B, 37.2 ± 4.0 cmH2O in group C, and 39.0 ± 1.7 cmH2O in group D, which was statistically significant. Histologically, the fibrin layer infiltrated the lung parenchyma and covered the defect in group A, but not in the other groups.

CONCLUSIONS

The intraparenchymal injection of fibrinogen combined with instillation of thrombin created an effective fibrin layer associated with early pleural regeneration that reliably prevented pleural air leaks.

Changes of superoxide dismutase activity and ascorbic acid in focal cerebral ischaemia in rats

Free radical reactions are supposed to cause ischaemic brain damage, and active oxygens can initiate these chains reaction. If active oxygens play important roles in ischaemic brain damage, the activity of superoxide dismutase, scavenger of superoxide anion, is supposed to decrease in ischaemic brain. The reduced form of ascorbic acid also scavenges superoxide anion. In rat middle cerebral artery focal ischaemia, we investigated the changes in superoxide dismutase activity and the concentration of reduced ascorbate up to 48 hours. Middle cerebral artery territory of each cerebral hemisphere was homogenized. The supernatant was divided into two aliquots; one was dialysed to remove ascorbate and the other was not. The enzyme activity of the dialysed specimen from the ischaemic hemisphere did not decrease within 4 h after the arterial occlusion. The activity of the dialysed specimen from the nonischaemic side remained unchanged during the examination. Reduced ascorbate levels in nondialysed samples showed similar changes to the superoxide dismutase activities in the dialysed samples. Our data suggest that ascorbic acid may exert the enzyme activity and that the enzyme activity remains at the normal level in the early phase of ischaemia despite the irreversible ischaemic changes that take place within 4 h after the onset of ischaemia.

Spontaneous Regression of Metastatic Extraskeletal Myxoid Chondrosarcoma

Spontaneous regression of tumors is very unusual and is defined as a partial or complete disappearance of metastatic tumors without any treatment. This phenomenon has been reported in almost all types of cancer. The patient was a 25-year-old woman who presented with multiple pulmonary nodules on her bilateral lungs on the annual chest roentgenograph. Simultaneously, a swelling mass on her subcutaneous inguinal region was observed. The diagnosis of the inguinal mass was extraskeletal myxoid chondrosarcoma. The inguinal mass and pulmonary nodules spontaneously regressed without any treatment after biopsy. The patient was doing well without evidence of recurrence at 1 year after the operation without any additional therapy. Our case is the first clinical one that indicated a possibility of histologic regression of extraskeletal myxoid chondrosarcoma.

Impact of comorbidity index on morbidity and survival in non-small cell lung cancer

Background

The number of surgeries in older patients with comorbidities is constantly growing. The present study examined the impact of comorbidity on postoperative complications and long-term survival in patients with completely resected non-small cell cancer.

Methods

Between 2004 and 2008, 423 patients with non-small cell lung cancer underwent complete resection. A retrospective comparison of perioperative mortality, morbidity, Charlson comorbidity index (CCI), and postoperative length of hospital stay was performed.

Results

The number of patients with CCI 0, 1–2, and ≥3 was 226, 170 and 27, respectively. The 5-year overall survival was 88% among patients with CCI 0, and 84% in those with CCI ≥1 ( p = 0.05) in all pathological stages. The CCI 0 group had significantly better overall survival than CCI 0 group and 30 (15%) in the CCI ≥1 group ( p = 0.024). Length of stay was shorter in the CCI 0 group (11 ± 5 days) than in the CCI ≥1 group (15 ± 19 days, p = 0.015).

Conclusions

A high CCI correlated with higher postoperative morbidity and longer length of stay. We identified better a prognosis in patients with CCI 0 compared to those with CCI 1–2.

Dry pleurisy complicating solitary pulmonary nodules caused by Mycobacterium avium: a case report

INTRODUCTION

Mycobacterium avium complex (MAC) lung disease presenting as a solitary pulmonary nodule (MAC-SPN) is often asymptomatic, is more common in middle to old age, and mimics lung cancer or tuberculoma. We report herein a case of MAC-SPN in an immunocompetent young adult patient, presenting with persistent chest pain and a subacutely progressive nodule with high intense (18)F-fluorodeoxyglucose uptake. Histological examination of resected specimens revealed pleurisy, which is a rare finding of MAC-SPN.

CASE PRESENTATION

A 36-year-old Japanese male presented with chest pain and a subacutely progressive pulmonary nodule. Positron emission tomography-computed tomography showed high intense (18)F-fluorodeoxyglucose uptake in the nodule. Owing to his continuous chest pain and subacutely progressive nodules, wedge resection was performed using video-assisted thoracoscopic surgery. Histological examination revealed an epithelioid granuloma and pleurisy, and the lung tissue culture was positive for mycobacteria identified as M. avium.

CONCLUSION

This is the first report of MAC-SPN occurring with persistent chest pain, suggesting that MAC should be considered in the differential diagnosis of a solitary pulmonary nodule, even for patients who experience persistent chest pain. As in the present case, surgical resection with video-assisted thoracoscopic surgery is a reasonable approach to the diagnosis and treatment of MAC-SPN with possible malignancy, especially as MAC can be diagnosed using resected lung tissue culture with histological confirmation.

Successful resumption of tocilizumab for rheumatoid arthritis after resection of a pulmonary Mycobacterium avium complex lesion: a case report

Background

Biological agents inhibiting TNF-α and other molecules involved in inflammatory cascade have been increasingly used to treat rheumatoid arthritis (RA). However, it remains controversial whether biological agents can be used safely in a patient with an underlying chronic infectious disease.

Case presentation

A 63-year-old woman who had been treated with tocilizumab (TCZ), anti-interleukin-6 receptor antibody, for RA presented to our outpatient clinic due to hemoptysis. She was diagnosed with pulmonary Mycobacterium avium complex (MAC) infection, and high-resolution computed tomography (HRCT) showed a single cavitary lesion in the right upper lobe. After diagnosis of pulmonary MAC disease, TCZ was discontinued and combination chemotherapy with clarithromycin, rifampicin, ethambutol and amikacin was started for MAC pulmonary disease. Since the lesion was limited in the right upper lobe as a single cavity formation, she underwent right upper lobectomy. As her RA symptoms were deteriorated around the operation, TCZ was resumed. After resumption of TCZ, her RA symptoms improved and a recurrence of pulmonary MAC infection has not been observed for more than 1 year.

Conclusion

This case suggested that TCZ could be safely reintroduced after the resection of a pulmonary MAC lesion. Although the use of biological agents is generally contraindicated in patients with pulmonary MAC disease, especially in those with a fibrocavitary lesion, a multimodality intervention for MAC including both medical and surgical approaches may enable introduction or resumption of biological agents.

Twenty-year trends in neonatal surgery based on a nationwide Japanese surveillance program

AIM

To discuss the chronological changes observed in a national survey of neonatal surgery in Japan performed every 5 years by the Committee in the Japanese Society of Pediatric Surgeons.

METHODS

We analyzed the data obtained for 20 years from 1993 to 2013 and herein report the chronological changes.

RESULTS

The number of summarized cases was least in 1993, with 2806 cases, and subsequently increased to 3753 cases in 2013. The mortality rate among the patients with maternal transport linearly decreased (p = 0.0386). Although the proportion of extremely low birth weight infants linearly increased (p = 0.0014), with an annual rate of +0.39 %, the mortality rate linearly decreased (p = 0.0010), with an annual rate of -1.68 %. Moreover, the overall mortality rate linearly decreased (p = 0.0002), with an annual rate of -0.26 %. Most diseases were observed to exhibit a decline in the mortality rate with the same trend as overall mortality. The decline in the mortality rate was most robust with respect to congenital diaphragmatic hernia (CDH). The mortality rates, except for that of CDH, omphalocele, esophageal atresia, and intestinal perforation, declined to 5 % or lower by 2013.

CONCLUSIONS

The present findings may be the result of remarkable progress in perinatal management.

Thirty-day outcomes after lobectomy or segmentectomy for lung cancer surgery

Background

Although lobectomy has been the standard operation for clinical T1aN0M0 non-small cell lung cancer, recent studies have shown that segmentectomy could be a substitute for lobectomy. However, the differences between lobectomy and segmentectomy in terms of perioperative complications have not been fully evaluated.

Methods

Between February 2006 and February 2013, 100 patients underwent lobectomy and 111 underwent segmentectomy for clinical T1aN0M0 non-small-cell lung cancer. We performed a retrospective comparison of perioperative morbidity, age, sex, pulmonary function, and Charlson comorbidity index in the 2 groups. Data were analyzed for all patients and for their propensity score-matched pairs.

Results

The incidence of postoperative complications in the segmentectomy group ( n = 21, 19%) was significantly higher than that in the lobectomy group ( n = 7, 7%; p < 0.01). The average operative time of 263 ± 64 min and estimated blood loss of 133 ± 125 mL for segmentectomy were significantly greater than those for lobectomy (201 ± 61 min and 88 ± 101 mL). In propensity score-matched analysis, the mean operative time of 270 ± 70 min for segmentectomy was longer than that for lobectomy (202 ± 67 min). Postoperative complications were more frequent in the segmentectomy group than in the lobectomy group (19.6% vs. 6.5%, p = 0.03).

Conclusions

Although segmentectomy offers preservation of pulmonary function, significantly more postoperative complications occurred in the segmentectomy group. Surgeons should bear in mind that complications can happen more frequently after segmentectomy than after lobectomy for T1aN0M0 non-small-cell lung cancer.

Survival predictors after resection of lung metastases of head or neck cancers

Background

Pulmonary metastasectomies are performed for a variety of cancers, though few reports have examined their merit for head and neck cancers. This study examined the relationship between clinical and pathological characteristics and survival after resection of lung metastases of these cancers.

Methods

Between 1986 and 2013, 34 patients presenting with pulmonary metastases of primary head or neck cancers underwent surgical resections at our institution. We retrospectively analyzed their clinical and pathological characteristics and the patients’ survival after metastasectomy in search of adverse prognostic factors.

Results

The primary sites of cancer were: the tongue in eight patients, the pharynx and salivary glands each in seven, the larynx in five, and miscellaneous sites in seven patients. Squamous cell carcinoma (SCC) was present in 19, adenoid cystic carcinomas in 10, and other diagnoses in five patients. The median disease-free interval (DFI) between the initial surgery and the metastasectomies was 40 months. The overall five-year survival rate was 57.9%, and median survival time was 77 months. By single variable analysis, a DFI of ≤26 months, age ≥60 years, and histology of SCC were predictors; by multiple variable analysis, a short DFI (P = 0.018) and older age (P = 0.046) remained independent predictors of poor clinical outcomes.

Conclusions

Young age and a long DFI are factors in favor of pulmonary metastasectomy after surgical treatment of primary head or neck cancers.