Association between atherosclerosis and height loss among older individuals.

Atherosclerosis and height loss are each reportedly associated with cardiovascular disease. However, no studies have found an association between atherosclerosis and height loss. A retrospective study of 2435 individuals aged 60-89 years who underwent annual health check-ups was conducted. Atherosclerosis was defined as carotid intima-media thickness (CIMT) ≥ 1.1 mm. Height loss was defined as being in the highest quintile of height decrease per year, as in our previous studies. Among study participants, 555 were diagnosed as having atherosclerosis. Independent of known cardiovascular risk factors, atherosclerosis was positively associated with height loss. The adjusted odds ratio (OR) was 1.46 (95% confidence interval, 1.15, 1.83). Essentially the same associations were observed for men and women. The adjusted OR (95% CI) was 1.43 (1.01, 2.04) for men and 1.46 (1.07, 1.99) for women. Among older individuals, atherosclerosis is associated with height loss. This result can help clarify the mechanism underlying the association between height loss and cardiovascular disease.

Antimicrobial resistance patterns of Streptococcus uberis isolates from bovine milk in Chiba prefecture, Japan: association between multidrug resistance and clonal complex 996.

Streptococcus uberis is one of major pathogens causing bovine mastitis. However, there is poor information on antimicrobial resistance (AMR) among the Japanese isolates. To provide treatment information for the mastitis caused by S. uberis in Japan, we aimed to clarify AMR patterns of the isolates from bovine milk mainly in Chiba. AMR phenotyping/genotyping [blaZ-erm(A)-erm(B)-mef(A)-linB-lnuD-tet(M)-tet(O)-tet(K)-tet(L)-tet(S)] and multilocus sequence typing were performed to analyze relationships between AMR patterns and clonal complexes (CCs). Resistance to tetracycline-, macrolide-, and lincosamide-classes was mainly associated with possession of tet(O), tet(S), erm(B), linB, and lnuD genes. CC996 was significantly associated with multidrug resistance (P<0.0001). These findings will aid Chiba farm animal clinics in treating bovine mastitis.

ctDNA improves prognostic prediction in relapsed/refractory MM receiving ixazomib, lenalidomide, and dexamethasone.

It remains elusive how driver mutations, including those detected in circulating tumor DNA (ctDNA), affect prognosis in relapsed/refractory multiple myeloma (RRMM). Here we performed targeted-capture sequencing using bone marrow plasma cells (BMPC) and ctDNA of 261 RRMM cases uniformly treated with ixazomib, lenalidomide, and dexamethasone in a multicenter, prospective, observational study. We detected 24 and 47 recurrently mutated genes in BMPC and ctDNA, respectively. In addition to clonal hematopoiesis-associated mutations, varying proportion of driver mutations, particularly TP53 mutations (59.2% of mutated cases), were present in only ctDNA, suggesting their subclonal origin. In univariable analyses, ctDNA mutations of KRAS, TP53, DIS3, BRAF, NRAS, and ATM were associated with worse progression-free survival (PFS). BMPC mutations of TP53 and KRAS were associated with inferior PFS, while KRAS mutations were prognostically relevant only when detected in both BMPC and ctDNA. A total number of ctDNA mutations in the six relevant genes was a strong prognostic predictor (2-year PFS rates: 57.3%, 22.7%, and 0% for 0, 1, and ≥ 2 mutations, respectively) and independent of clinical factors and plasma DNA concentration. Using the number of ctDNA mutations, plasma DNA concentration, and clinical factors, we developed a prognostic index (ctRRMM-PI), classifying patients into three categories with 2-year PFS rates of 57.9%, 28.6%, and 0%. Serial analysis of ctDNA mutations in 94 cases revealed that TP53 and KRAS mutations frequently emerge after therapy. Thus, we clarify the genetic characteristics and clonal architecture of ctDNA mutations and demonstrate their superiority over BMPC mutations for prognostic prediction in RRMM.

The impact of glucocorticoid use on the outcomes of rheumatoid arthritis in a multicenter ultrasound cohort study.

OBJECTIVE: Glucocorticoids are effective in treating rheumatoid arthritis (RA) when used appropriately considering the balance of the risks and benefits, especially at low doses. We aimed to evaluate the response of biologic and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) in patients having already been treated with glucocorticoids. METHODS: We reviewed RA patients treated with b/tsDMARDs in a prospective multicenter ultrasound cohort study. We compared the differences in the clinical characteristics at baseline and outcomes at 12 months between the two groups having been treated with and without glucocorticoids at baseline. The differences in the clinical characteristics and the treatments were balanced by the inverse probability weighting (IPW) with the propensity score. RESULTS: Of 307 patients with RA, 160 patients were treated with glucocorticoids at baseline. The median dose of glucocorticoids was equivalent to 5.0 mg/day of prednisolone. Significant differences were in age and concomitant methotrexate use, composite measures for the disease activity, and the ultrasound grayscale score at baseline. Patients treated with glucocorticoids had less frequent remissions defined by composite measures and ultrasound findings than those treated without glucocorticoids. These significant differences in the achievement of remissions remained robust even after adjusting differences in the clinical characteristics and the treatments between the two groups by IPW. CONCLUSION: RA patients treated with glucocorticoids had a higher disease activity at baseline and a poorer response to treatments with b/tsDMARDs than those without glucocorticoids. The states of patients requiring glucocorticoids might be associated with the poor response to the b/tsDMARDs.

A type I interferon regulatory network for human plasmacytoid dendritic cells based on heparin, membrane-bound and soluble BDCA-2.

Plasmacytoid dendritic cells (pDCs) produce type I interferons (IFNs) after sensing viral/bacterial RNA or DNA by toll-like receptor (TLR) 7 or TLR9, respectively. However, aberrant pDCs activation can cause adverse effects on the host and contributes to the pathogenesis of type I IFN-related autoimmune diseases. Here, we show that heparin interacts with the human pDCs-specific blood dendritic cell antigen 2 (BDCA-2) but not with related lectins such as DCIR or dectin-2. Importantly, BDCA-2-heparin interaction depends on heparin sulfation and receptor glycosylation and results in inhibition of TLR9-driven type I IFN production in primary human pDCs and the pDC-like cell line CAL-1. This inhibition is mediated by unfractionated and low-molecular-weight heparin, as well as endogenous heparin from plasma, suggesting that the local blood environment controls the production of IFN-α in pDCs. Additionally, we identified an activation-dependent soluble form of BDCA-2 (solBDCA-2) in human plasma that functions as heparin antagonist and thereby increases TLR9-driven IFN-α production in pDCs. Of importance, solBDCA-2 levels in the serum were increased in patients with scrub typhus (an acute infectious disease caused by Orientia tsutsugamushi) compared to healthy control subjects and correlated with anti-dsDNA antibodies titers. In contrast, solBDCA-2 levels in plasma from patients with bullous pemphigoid or psoriasis were reduced. In summary, this work identifies a regulatory network consisting of heparin, membrane-bound and solBDCA-2 modulating TLR9-driven IFN-α production in pDCs. This insight into pDCs function and regulation may have implications for the treatment of pDCs-related autoimmune diseases.

Small medial proximal tibial angle is a radiographic finding strongly associated with less coronal alignment correction under valgus stress in medial knee osteoarthritis.

PURPOSE: The degree to which varus knees can be corrected manually is important when considering total versus unicompartmental knee arthroplasty (UKA). The primary aim was to clarify the relationship between the degree of coronal alignment correction and radiographic parameters involved in UKA prognosis using preoperative full-length lower extremity valgus stress radiography. The secondary aim was to identify the factors affecting alignment correction. METHODS: This retrospective observational study included 115 knees with medial osteoarthritis that underwent knee osteotomy or arthroplasty. Percent mechanical axis without valgus stress (%MA: neutral, 50%; varus, <50% and valgus, >50%), mechanical lateral distal femoral angle, lateral bowing femoral angle, medial proximal tibial angle (MPTA), joint line convergence angle, medial and lateral joint space width (LJSW) and medial femoral and tibial joint osteophyte size were measured using preoperative full-length weight-bearing radiographs. Correlation and multiple linear regression analyses were used to assess associations between parameters and %MA with valgus stress or amount of %MA change (%MA with valgus stress minus %MA without valgus stress). RESULTS: %MA with valgus stress was correlated with all radiographic parameters. %MA change was correlated with parameters except for MPTA and LJSW. Multiple regression analyses showed that %MA without valgus stress and MPTA were associated with both %MA with valgus stress and %MA change. When %MA with valgus stress was set at 30%, 40% and 50%, MPTA cutoff values were 81.6°, 83.5° and 84.9°, and cutoffs for %MA without valgus stress were 10.7%, 17.1% and 25.1%, respectively. CONCLUSION: Small MPTA is strongly associated with less alignment correction under valgus stress in varus knees. The finding is useful in surgical planning, especially to avoid undercorrection with UKA when valgus stress radiographs are unavailable. LEVEL OF EVIDENCE: Level III.

Successful treatment of streptococcal toxic shock syndrome complicated by primary peritonitis and bilateral empyema in a healthy young woman: Identification of uncommon clone emm103 and novel sequence type 1363.

Streptococcal toxic shock syndrome (STSS) has a dramatic clinical course and high mortality rate. Here, we report a case of STSS complicated by primary peritonitis and bilateral empyema. A previously healthy young woman was diagnosed with STSS complicated by primary peritonitis and bilateral empyema. Blood culture results on admission were negative. Sever shock, respiratory failure, systemic inflammation, thrombocytopenia, renal failure, ascites, and pleural effusion occurred, mimicking thrombocytopenia, anasarca, fever, reticulin fibrosis/renal failure and organomegaly (TAFRO) syndrome. Retesting blood cultures identified Streptococcus pyogenes. Gram staining of ascites and pleural fluid indicated gram-positive cocci in chains. Antibiotics, immunoglobulins, and surgical intervention led to recovery without complications. Ex-post genotypic analyses showed uncommon emm103.0 (cluster E3) of emm long sequence (784 base) and novel sequence type 1363. STSS diagnosis can be difficult as it mimics other systemic inflammatory diseases. Therefore, it is crucial for clinicians to perform microbiological examinations from infection foci, even if the initial culture is negative.

Residual Deformity of the Trochlea After Non-displaced Supracondylar Fracture in a Child: A Case Report.

Residual deformity of the trochlea after fractures of the distal end of the humerus in children is well known and is referred to as fishtail deformity. Despite numerous reports on this entity, the reason for various types of fractures with the same results remains unknown. Fishtail deformities after non-displaced supracondylar fractures are very rare. A 7-year-old boy with a non-displaced supracondylar fracture was treated conservatively. Three years later, the patient returned to our hospital complaining of mild elbow pain. Radiography revealed a fishtail deformity of the trochlea due to the premature fusion of the epiphysis. At the latest follow-up at the age of 17 years, only a marginal limitation at the excursion of the elbow was observed, and no additional treatment was needed. Fishtail deformities can occur even after a non-displaced supracondylar fracture. Long-term follow-ups are required in children with distal humeral fractures.

Draft genome sequence of emm103/ST1363 Streptococcus pyogenes strain AB1, isolated from the blood of a woman with peritonitis and toxic shock syndrome.

We report the draft genome sequence of Streptococcus pyogenes strain AB1 isolated from the blood of a woman with peritonitis-toxic shock syndrome. The genome measured 1.855 Mbp, with a G + C content of 38.3%. Sequences unmapped to the reference genome sequence of M1 SF370 (GenBank accession number AE004092.2) were characterized.

Platypnoea-orthodeoxia syndrome in COVID-19 pneumonia patients: An observational study.

This retrospective observational study aimed to assess the clinical characteristics of platypnea-orthodeoxia syndrome in patients with coronavirus disease 2019 (COVID-19) treated using mechanical ventilation or high-flow nasal canula. We analyzed 42 consecutive patients with COVID-19 from January 2020 to March 2022. The primary outcomes were the incidence of platypnea-orthodeoxia syndrome, the time with required long-term oxygen therapy, and short-term prognosis. Additionally, we examined the relationships between platypnea-orthodeoxia syndrome and COVID-19 severity, the time with long-term oxygen therapy, and short-term prognosis. Of the 42 included patients, 15 (35.7 %) had platypnea-orthodeoxia syndrome. Although mortality was not significantly different between both groups, the oxygen withdrawal rate in the platypnea-orthodeoxia syndrome group was significantly lower than that in the group without this syndrome. Clinical staff should be aware of the possibility of platypnea-orthodeoxia syndrome during positional changes in patients with COVID-19. Recognizing POS can improve early detection, countermeasures, and safety during physiotherapy.

A Learning Program for Treatment Recommendations by Molecular Tumor Boards and Artificial Intelligence.

Importance: Substantial heterogeneity exists in treatment recommendations across molecular tumor boards (MTBs), especially for biomarkers with low evidence levels; therefore, the learning program is essential. Objective: To determine whether a learning program sharing treatment recommendations for biomarkers with low evidence levels contributes to the standardization of MTBs and to investigate the efficacy of an artificial intelligence (AI)-based annotation system. Design, Setting, and Participants: This prospective quality improvement study used 50 simulated cases to assess concordance of treatment recommendations between a central committee and participants. Forty-seven participants applied from April 7 to May 13, 2021. Fifty simulated cases were randomly divided into prelearning and postlearning evaluation groups to assess similar concordance based on previous investigations. Participants included MTBs at hub hospitals, treating physicians at core hospitals, and AI systems. Each participant made treatment recommendations for each prelearning case from registration to June 30, 2021; participated in the learning program on July 18, 2021; and made treatment recommendations for each postlearning case from August 3 to September 30, 2021. Data were analyzed from September 2 to December 10, 2021. Exposures: The learning program shared the methodology of making appropriate treatment recommendations, especially for biomarkers with low evidence levels. Main Outcomes and Measures: The primary end point was the proportion of MTBs that met prespecified accreditation criteria for postlearning evaluations (approximately 90% concordance with high evidence levels and approximately 40% with low evidence levels). Key secondary end points were chronological enhancements in the concordance of treatment recommendations on postlearning evaluations from prelearning evaluations. Concordance of treatment recommendations by an AI system was an exploratory end point. Results: Of the 47 participants who applied, 42 were eligible. The accreditation rate of the MTBs was 55.6% (95% CI, 35.3%-74.5%; P < .001). Concordance in MTBs increased from 58.7% (95% CI, 52.8%-64.4%) to 67.9% (95% CI, 61.0%-74.1%) (odds ratio, 1.40 [95% CI, 1.06-1.86]; P = .02). In postlearning evaluations, the concordance of treatment recommendations by the AI system was significantly higher than that of MTBs (88.0% [95% CI, 68.7%-96.1%]; P = .03). Conclusions and Relevance: The findings of this quality improvement study suggest that use of a learning program improved the concordance of treatment recommendations provided by MTBs to central ones. Treatment recommendations made by an AI system showed higher concordance than that for MTBs, indicating the potential clinical utility of the AI system.

Human Keratinocyte Entry of Noninvasive Streptococcus dysgalactiae Subsp. equisimilis from Humans and Companion Animals: Relatedness with Lancefield Group, Source, Virulence-Associated Genes, and Antimicrobial Resistance Phenotype.

We evaluated the cell invasion ability (CIA) of non-invasive Streptococcus dysgalactiae subsp. equisimilis using human keratinocytes and determined the association of CIA populations with their hosts and microbiological traits. Forty-two isolates from humans and companion animals were selected with host information. In addition to CIA, virulence-associated gene (VAG, spegg-ska-scpA-inlA-sicG-brpA-prtF1-prtF2-lmb-cbp-srtp1-srtp2) profiling, emm genotyping, multilocus sequence typing, and antimicrobial resistance (AMR) phenotyping/genotyping were performed. We designated CIA values higher than the mean of all isolates as high-frequency and those lower than the mean as low-frequency. Differences in the CIA between the different sources and Lancefield groups were assessed. We analyzed the association between high- and low-frequency CIA and VAG, emm genotype, sequence type/clonal complex, and AMR phenotype/genotype. Based on the mean (19.368 colony-forming units/100 cells) of 42 isolates, eight isolates had high-frequency CIA, whereas 34 had low-frequency CIA. We found an association between low-frequency CIA population and group G isolates, as well as a link between high-frequency CIA population and group C isolates. We also observed associations between low-frequency CIA population and oral/respiratory tract origin, ska, scpA, and lmb detection, and the AMR phenotype. Our observations suggest potential associations between high-/low-frequency CIA and the group, source, VAG, and AMR phenotypes.

A prospective, multicenter, observational study of ixazomib plus lenalidomide-dexamethasone in patients with relapsed/refractory multiple myeloma in Japan.

Real-world studies permit inclusion of a more diverse patient population and provide more information on the effectiveness of treatments used in routine clinical practice. This prospective, multicenter, observational study investigated the effectiveness and safety of ixazomib plus lenalidomide and dexamethasone (IRd) in 295 patients with relapsed/refractory multiple myeloma (RRMM) in routine clinical practice in Japan. Patients had a median age of 74 years, 80.0% were aged ≥ 65 years, 42.0% had received ≥ 3 lines of prior treatment, and 28.5% were "frail" according to the International Myeloma Working Group frailty score. After a median follow-up of 25.0 months, median progression-free survival (PFS) was 15.3 (95% CI 12.4-19.5) months, while median overall survival was not reached. The overall response rate was 53.9%, and 31.5% of patients had a very good partial response or better. In the subgroup analysis, median PFS was better in patients with 1 versus 2 or ≥ 3 lines of prior treatment (29.0 vs 19.2 or 6.9 months) and paraprotein versus clinical relapse (16.0 vs 7.9 months), but median PFS was not notably affected by frailty score or age group. Dose adjustment was more frequent among patients aged > 75 years, especially early after IRd treatment initiation. Treatment-emergent adverse events (TEAEs) of any grade occurred in 84.4% of patients and 24.7% of patients discontinued treatment due to TEAEs; no new safety concerns were found. These findings suggest that oral IRd triplet regimen is an effective and tolerable treatment option for RRMM patients in real-world settings outside of clinical trials.ClinicalTrials.gov identifier: NCT03433001; Date of registration: 14 February 2018.

Initial real-world experience of clazosentan for subarachnoid hemorrhage in Japan.

BACKGROUND: Cerebral vasospasm (CVS) is one of the most critical factors associated with clinical outcomes of patients with subarachnoid hemorrhage (SAH). Clazosentan has been investigated worldwide as a prophylactic agent to prevent CVS. We evaluated a new CVS management protocol which included clazosentan. METHODS: Consecutive 138 patients with SAH, hospitalized in our institution between January 2017 and December 2022, were included in this study. Baseline characteristics, clinical findings, and operative records were analyzed retrospectively. From May 2022, 10 mg/h clazosentan was co-administered with fasudil to all patients according to the indication in the Japanese label. Patients admitted before this date received the conventional combined protocol using the fasudil hydrochloride, nicardipine, and ozagrel. RESULTS: Eighteen (13.0%) patients received the new protocol during the CVS period (defined as day 1 up to day 14 after SAH onset). There were 54 (39.1%) elderly patients aged 75 years or older. Seventy-two (52.2%) patients underwent neurosurgical clipping, whereas 55 (39.9%) patients received endovascular coiling. Among the patients with new protocol, only one patient (5.6%) had symptomatic CVS, compared with 18 patients (15.0%) in those with conventional protocol. More patients who received the new protocol had fluid retention compared with control group (38.9% [7/18] vs. 8.3% [10/120]). Other results did not differ between the two groups. CONCLUSIONS: Clinical outcomes of the new protocol were comparable to those of conventional protocol. Clazosentan may simplify anti-vasospasm treatment. Fluid retention was a specific side-effect of clazosentan, which requires attention especially in the first half of the CVS period.

Preoperative radiographs underdiagnose the severity of lateral femoral and medial trochlear cartilage damage in varus osteoarthritis knees.

OBJECTIVE: This study evaluated whether preoperative radiographs accurately predicted intra-articular cartilage damage in varus knees. METHODS: The study assessed 181 knees in 156 patients who underwent total knee arthroplasty. Cartilage damage was graded by two examiners with the International Cartilage Repair Society (ICRS) classification; one used knee radiographs and the other used intraoperative photographs. It was then determined if this radiographic cartilage assessment over- or underestimated the actual damage severity. Knee morphological characteristics affecting radiographic misestimation of damage severity were also identified. RESULTS: The concordance rate between radiographic and intraoperative assessments of the medial femoral condyle was high, at around 0.7. Large discrepancies were found for the lateral femoral condyle and medial trochlear groove. Radiographic assessment underestimated cartilage damage on the medial side of the lateral femoral condyle due to a large lateral tibiofemoral joint opening and severe varus alignment (both r = -0.43). Medial trochlear damage was also underdiagnosed, in cases of residual medial tibiofemoral cartilage and shallow medial tibial slope (r = -0.25 and -0.21, respectively). CONCLUSIONS: Radiographic evaluation of knee osteoarthritis was moderately practical using ICRS grades. Lateral femoral and medial trochlear cartilage damage tended to be misestimated, but considering morphologic factors might improve the diagnostic rate.

Comparison of knee kinematics and ligament forces in single and multi-radius cruciate-retaining total knee arthroplasty: A computer simulation study.

BACKGROUND: The single-radius design in total knee arthroplasty has been designed to develop a more fixed flexion-extension axis without mid-flexion instability compared with the multi-radius design. It remains unclear whether differences between the multi-radius and single-radius designs can affect kinematics and collateral ligament forces. This study aimed to simulate knee kinematics and kinetics between single-radius and multi-radius models using a musculoskeletal computer model. METHODS: The single-radius and multi-radius femoral components were virtually implanted in a computer simulation using the same tibial insert. The effects of implant design on kinematics and medial collateral ligament forces during squatting and gait activities were analyzed. RESULTS: During squatting, the multi-radius model exhibited paradoxical anterior translation on both the medial and lateral flexion facet center where peak anterior translation was 2.4 mm for medial flexion facet center and 2.2 mm for the lateral flexion facet center, while the peak anterior translation of the single-radius model was less than 1 mm at early flexion. A rapid decrease in medial collateral ligament tension was observed in the early flexion phase in the multi-radius model, which occurred simultaneously with paradoxical anterior translation, whereas the relatively constant medial collateral ligament tension was observed in the single-radius model. During gait activity, the single-radius model exhibited a more posterior position than the multi-radius model. CONCLUSION: These suggest that abrupt changes in the medial collateral ligament force influence anterior sliding of the femur, and that the single-radius design is a reasonable choice for prevention of mid-flexion instability.

Addition of Mechanical Lithotripsy to Endoscopic Papillary Large Balloon Dilation in Patients with Difficult Common Bile Duct Stones: A Retrospective Single-Center Study.

Introduction: This study aimed to compare the treatment outcomes of endoscopic papillary large-balloon dilation (EPLBD) with and without mechanical lithotripsy (ML) in removing difficult common bile duct stones. Methods: Patients with difficult common bile duct stones treated with EPLBD, with or without ML, at the Eastern Chiba Medical Center between April 2014 and March 2020, were retrospectively evaluated. The rates of cumulative recurrence and complications were compared between the two groups. Results: Overall, 122 patients (n = 44, EPLBD + ML and n = 78, EPLBD) treated by 12 gastroenterologists were included. Patients in the EPLBD + ML group were older (85 years versus 81.5 years) and had larger maximum stone diameter (15 mm versus 12.5 mm) than those in the EPLBD group. Compared with the EPLBD group, the EPLBD + ML group required more endoscopic retrograde cholangiopancreatography (ERCP) procedures (≥2) (86% versus 67%) and longer total ERCP time after reaching the papilla (78.5 minutes versus 25 minutes). Complication rates were not significantly different (9.1% versus 12.8%); however, the cumulative recurrence rates were higher in the EPLBD + ML group than in the EPLBD group (69.4% versus 23.5% at 4 years). Conclusion: Although there were no differences in complication rates, the long-term recurrence rate was higher in the EPLBD + ML group than in the EPLBD group. This study emphasizes the added burden imposed by performing ML during ERCP and suggests that by appropriate case selection, it is possible to treat cases of difficult biliary stones using EPLBD without ML.

Feasibility of Organ Transportation by a Drone: An Experimental Study Using a Rat Model.

BACKGROUND: Recently, the successful delivery of organs for transplantation using drones was reported. We investigated the influence of transportation by drones on the quality of liver grafts using a rat model. METHODS: Livers of 12 rats (8 and 32 weeks old) were divided into 2 groups of six. Livers were split into 2 parts and allocated to the drone or control groups (both n = 12). The drone experiment was conducted between islands in Nagasaki Prefecture, Japan. The distance between the islands was 12 km. Livers of the drone group were transported by a multicopter at a speed of 30 km-40 km/h over 60 m above sea level. Transported liver quality was analyzed by histology, and biochemistry data were compared between groups. RESULTS: Cold ischemia time did not differ between groups (902 min and 909 min, respectively). There were no differences in macroscopic findings regarding coloration and damage between groups. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) in preservation fluid were graft weight-corrected and compared, and no significant differences were found between groups: AST/g (4.61 vs 4.81 IU/L), ALT/g (2.78 vs 2.92 IU/L), and ALP/g (39.1 vs 37.0 IU/L). Immunochemical staining showed no significant difference between groups for terminal deoxynucleotidyl transferase dUTP nick and labeling staining (141 vs 113 cells), CD163 (818 vs 870 cells), and TNF-α (1.25 vs 1.41 scores). CONCLUSIONS: The simulation experiment of organ transport for transplantation by drones was successfully conducted. There were no differences in the quality of livers transported by drones or other means. Further studies including large-animal experiments could lead to future clinical applications.